Special Section : Food Biotechnology

 

Prebiotic Activity of Xylooligosaccharides from Corncob

Lorena Pedraza, Héctor Toribio, Rebeca Romo, Silvana Arreola, Mirely Guevara

  • Abstract

    Prebiotics are substances that promote the growth of beneficial microorganisms (probiotics) inthe gut. Probiotics are microorganisms such as bacteria or yeast that is believe to improve health.The xylooligosaccharides (XOS) are a type of prebiotic substances, these compounds are oligomers formed by xylose units and can be obtained by enzymatic hydrolysis of xylan. In this work the xylan was obtained through thermochemical pretreatment of the corncob, which is a by-product from corn processing. To analyse the prebiotic activity of XOS obtained from corncob and reagent grade xylan, they were tested in L. brevis, L. plantarum, L. acidophilus, L. rhamnosus cultures, and in a co-culture with Escherichia coli as a challenge microorganism to prove the bacteriostatic activity of lactobacilli strains.Xylooligosaccharides stimulated L. brevis and L. plantarumgrowth: these microorganisms grew faster than the other lactobacilli strains. L. acidophilus grew better in the presence of XOS and maintained the absorbance of the culture.biotec

    In the co-culture in presence of both XOS the challenge microorganism did not grow; lactobacilli colonies appeared in MRS agar. No colonies of E. coli grew in EMB plaques.

 

 Antioxidant Capacity of Extractable and Non-extractable Polyphenols of Pigmented Maize

 Gustavo A. Camelo-Méndez, Luis A. Bello-Pérez

  • Abstract

     Most research studies in food science have been focused in the field of dietarypolyphenols or phenolic compounds, but there is an important part of polyphenols not extracted with organic solvents and the reports are few of those compounds. Pigmented maize (mainly blue and red) have presented significant anthocyanins content and antioxidant capacity; however, the studies about phytochemical content of pigmented maize in Mexico and their biological effects are limited. The aim of this study was to evaluate the antioxidant capacity of extractable and non-extractable polyphenols of blue and red maize. Tota lpolyphenols was determined, as the sum of the polyphenols present in methanol: acetone: water extracts (extractable polyphenols), condensed tannins and hydrolysable polyphenolsnon-extractable polyphenols) in the corresponding residues of maize samples. The nonextractable polyphenols content was higher than extractable polyphenols. It was estimated that high percentage of phenolics could be more bio-accessible in the large intestine. In general, blue and red maize presented an antioxidant capacity (FRAP and ABTS assays). These results  are important for the use of maize-based foods, industrial and pharmaceutical products.  

 

Cultural and Biological Aspects of Production and Uptake of Camote De Cerro (Dioscorea spp.) In South of Strand of Lake Chapala

Hernández-Maldonado Gema, Leal-Robles Aida Isabel

  • Abstract

    Camote de cerro (Dioscorea spp.) is obtained through traditional gathering in wild environments in south of strand of Lake Chapala (in Jalisco and Michoacán states),local gatherers recognized varieties and preserved populations because of their knowledge (3). We conducted interviews to camote de cerro gatherers, consumers and merchants, and field visits in order to document their knowledge and management techniques of camote de cerro. For in vitro establishment were used MS (4). culture medium, it contains 30 g/L saccharose without PGRs 14 sterile seeds were maintained in a growth room at room temperature for a 16L: 18D photoperiod,. After germination 4 subcultures were performed under the same conditions. Camote de cerro gatherers identified two plants varieties, seven local medicinal uses for camote de cerro. Results of in vitro culture were: 11 seeds were contaminated and 3 were able to germinate. After 4 subcultures performed 103 plants were obtained. Was stablished a culture line for further analysis and microtuberization, thus could be material avaliable for camote de cerro production without affecting natural populations. 

 

Changes in Intestinal Microorganisms Influenced By Agave Fructansin A Digestive Tract Simulator.

Adán Hernández-Moedano, Esban Felipe Moreno-Ramos , Sara Elisa Herrera-Rodríguez, Marisela González-Avila

  • Abstract

    Agave tequilana Weber var azul fructans have potential use in dietary products and in drug delivery systems. They also have a potential use as dietary supplements because of their prebiotic properties, since them are resistant to hydrolysis by human digestive enzymes, the fructans can be used by intestinal microorganisms as a feed source by colonic microbiota. The prebiotic effect of an ingredient can be evaluated in terms of its selective effect on the growth of different bacterial groups in the human digestive tract. The purpose of this study was to evaluate the prebiotic effect of four different fructan fractions by studying the increase of bacterial growth with beneficial effects on human health such as Lactobacillus and Bifidobacterium, and the fructan’s effect in decreasing the growth of undesirable bacteria such as Clostridium. All results were compared with commercial chicory fructans (Orafti Synergy1), which is known to be a bifidogenic product. All experiments were done under human like physiological conditions using a human digestive tract simulator (HDTS). The four fructan fractions evaluated, hTF (DP>10), FOS (DP<10), dTF (Agave extract without minerals) and TF (total Agave extract), were settogether with microbiota in HDTS, and samples were collected after day 4 and 9, the colony forming units (CFU) were measured in all samples from the different reactors that mimic the ascending colon (AC), transverse colon (TC) and descending colon (DC). The results showed, of the four fractions evaluated, the dTF fructan fraction represents the best option for use as a prebiotic because it increased the probiotic effect observed by bacteria growth (lactobacilli and bifidobacteria) and reduced the growth of undesirable bacteria (clostridia). By promoting the growth of good bacteria and decreasing the growth of undesirable bacteria, these results suggest that dTF could offer health benefits to consumers. 

 

Antioxidant Activity of Processed and Raw Seed Byproduct from Jalapeño Pepper

Claudia J. Sandoval-Castro; Maribel Valdez-Morales; Xiomara P. Perea-Domínguez;Sergio Medina-Godoy; and L. Gabriela Espinosa-Alonso

  • Abstract

    Mexico is the largest producer of green pepper in the world, and close to 20% of this production is industrially processed generating a byproduct that is considered a waste with a negative impact on the environment. This byproduct from Jalapeño pepper has not been characterized and no applications are propose for this material. Proximal composition of the byproduct obtained after slicing of scaled Jalapeño pepper was analyzed; and besides a sample of raw material in the same composition was obtained to determinate if the scalding process induces any variation in methanolic extract, total phenolic content and antioxidant activity. Proximal analysis of byproduct indicates that fiber (ca. 43.59 g/100g) is the main component after water elimination. Proteins (21.26 g/100 g) and lipids (17.26 g/100 g) are present in a considerable amount, suggesting further characterization. Raw material has a significant higher content of methanol extract that byproduct scalded (p ≤ 0.05). Regarding to total phenol content there was not significant difference between both materials (p > 0.05). Respecting to antioxidant activity, three methods were assessed: ABTS, DPPH and ORAC. Even when raw material shown higher antioxidant activity than scalded byproduct in the three methods evaluated, scalded byproduct still represent a potential source to obtain natural antioxidants for food industry. 

 

Isolation of Wild Edible Mycorrhizal Mushrooms

Lourdes Acosta-Urdapilleta, Marlen Mendoza-García, Nidia Obscura,Elba Villegas, Gerardo Díaz-Godinez, Maura Tellez-Tellez

  • Abstract

    Edible mycorrhizal mushrooms have been collected and consumed for centuries in indigenous communities and are part of the diet of its inhabitants. They have economic importance, as several communities supplement their income with the economic trade of these species in specific, in the state of Morelos in the community of Huitzilac these mushrooms are used for both self-supply and sale. Although these mushrooms have a great importance and potential in biotechnology, the collection of mycological strains HEMIM of the Mycology Laboratory of the CIB-UAEM still does not contain strains of wild edible mycorrhizal fungi. For this reason, the objective of this work was to isolate mycorrhizal fungi from the state of Morelos. The biological material was obtained from the community of Huitzilac in Morelos. Isolates from basidiomes were performed on potato dextrose agar (PDA) supplemented with malt; transfers were made to purify the strains, and isolates were incubated at 25 °C in the dark. Isolates were plated on PDA, malt extract agar (EMA) and whole wheat flour (HIT). Sixteen mycorrhizal fungi were isolated. Three mycorrhizal fungi isolates were successful (Russula brevipes, Cantharellus cibarius and Amanita caesarea), whose species will be later corroborated by identification tests. In general, a better mycelial growth of mycorrhizal fungi was observed when grown in EMA, followed by PDA andfinally on HIT. These results agree with previous work where PDA and malt extract were used for the growth of mycorrhizal fungi.

 

Spectral Characterization by FT-IR of Biogenic Amines

Jesboc Arodi Mendoza Ortega, Raúl Jacobo Delgado Macuil, Valentín López Gayoú,Orlando Zaca Morán

  • Abstract

    The biogenic amines (BA) are organic bases of low molecular weight biologically active. Foods with favorable conditions for the growth of microorganisms with amino acid decarboxylase may present the formation of BA. Excessive BA oral intake, may induceadverse reactions, such as toxicological effects and changes in blood pressure. BA analysis is important not only because of toxicity, but also to its use as a food quality indicators. Analytical methods commonly used for the determination of BA are the chromatographic, however, it are complex, expensive and it is time consuming during the process; for this reason the development of a technique based on spectroscopy, Fourier transform infrared (FT-IR), that allows an qualitative determination of BA is proposed. Spectral characterization by FT-IR of eight BA was obtained, which could be observed in thecharacteristic bands of amines, 3300-3500 cm-1 N-H stretching, 1500-1650 cm-1 bending NH, 1020-1350 cm-1 corresponding to stretching the C-N primary and secondary amines; and the band of 2800-3050 cm-1 (vibrational absorptions of C-H bonds) feature of the aliphatic, aromatic and heterocyclic of BA. The FT-IR analysis of each of the AB and AB mixture of 8 helped establish its characteristic spectral response, which established the basis for the qualitative determination of BA by FT-IR spectroscopy. 

 

Development of a Nano-immunosensor Composed of Proteins-Coated Gold Nanoparticles for Biosensing Applications

Leslie Susana Arcila-Lozano, Marlon Rojas-Lopez.

  • Abstract

    A colloidal immunosensor based on gold nanoparticles was developed. It was obtained by using gold nanoparticles conjugated with streptavidin and a biotinylated antibody in their surface. Gold nanoparticles (of nanometer size ~ 20 nm) were synthesized through the chemical reduction of chloroauric acid with sodium citrate. In order to determinate the critical protein concentration for covering the surface of the gold nanoparticles a titration experiment were carried out. The arrangement (gold nanoparticlestreptavidin- immunoglobulin) was characterized by UV/VIS spectroscopy and electron microscopy. 

 

Proximate Composition of Pleurotus Fruit Body Flour and Protein Concentrate

Cruz-Solorio, Angélica; Garín-Aguilar, M. Eugenia; Leal-Lara, Hermilo, Ramírez-Sotelo, M. Guadalupe and Valencia-del Toro, Gustavo

  • Abstract

    Protein concentrates are important in the food industries because added to food they increase the nutritional value and provide specific functional attributes. Edible mushrooms represent a viable alternative to obtain protein concentrates with an acceptable quality. In the present study protein concentrates were obtained from defatted flour of fruit bodies form two parental Pleurotus strain (POS and PCM) and their hybrid (PCM1xPOS1). The chemical analysis of flours and protein concentrates was carried out and also the content of soluble protein as function of pH was determined. The results indicate that the total biological efficiency for two flushes of PCM1xPOS1, PCM y POS strains was 77.8, 81.36 y 85.11%, respectively and the Mean mushroom size (MS) of POS strain (7.03 g) was higher than the others strains. The protein content in the three strains increased two fold in the protein concentrate ranged from 48.56 to 49.94% of protein. The ash and moisture content was similar in both flours and protein concentrate, while the fiber and carbohydrate content decreased; in contrast the fat content was lower in flours than in protein concentrates. Regarding the pH the higher concentration of soluble protein in flours (0.20 to 0.24g/L) and protein concentrates (2.25 to 2.68g/L) was presented with pH 12. The results show the potential of Pleurotus mushrooms in protein concentrates preparation.

 

Effect of Three Carbon Sources on the Expression of a Protein with Nutraceutical Properties

Clara Tinixcatl-Herández, Edgar Espinosa-Hernández, Jocksan Ismael Morales-Camacho, Silvia Luna-Suárez

  • Abstract

    The aim of this work was to assess the effect of carbon sources of low cost on the yield of the modified acidic subunit of amarantin, which is the most abundant protein in the seed of amaranth seed, this protein has an excellent aminoacidic balance and has been established as a model for the development of foods with high nutritional quality. Here we express the modified protein in two E coli strains, using 3 C sources, the yeast extract was the best source, as we identified the best yield in this medium. 

 

Determination of Loci of Productive Interest (κ-Casein, β- Lactoglobulin and α-Lactalbumin) Through Genetic Markers in a Milking Farm Animals from Toluca, Mexico

Daniel Serrano, Andrea Martínez, Marcela González-De la Vara, Angélica Espinoza- Ortega, Giovanna Peñuelas-Rivas, Juan Carlos Vázquez-Chagoyán

  • Abstract

    The selection of productive traits in animals is necessary in order to have more efficient farms, however traditional animal selection methods are very time consuming processes. Nowadays, for some productive traits, it is possible to perform genetic selection of animals through molecular markers, which help to make selection a time efficient process. The objective of the present study was to genotype animals (n=22) from a milking farm, through molecular markers for the A and B alleles of the genes α-Lactalbumin (α-LA), β- Lactoglobulin (β-LG) and κ-Casein (κ-CN) to identify the animals with an ppropriategenotype for milk production destined to cheese production. Here we genotyped all the animals from a milking farm and found that the frequency for the B alleles for the κ-CN, β- LG and α-LA are low medium and high, respectively. Furthermore, these genes keep Hardy-Weinberg equilibrium, suggesting that no selection pressure has been kept against any of these alleles recently. This information will be used to group animals according to their genotype to classify the milk for either fluid retail or cheese production. 

 

FTIR Determination of Protein Aggregates in Enzymatic Coagulation of Cow Milk

Gisela Clara Hernández, Raúl, Delgado Macuil, Marlon Rojas Lopez1, Héctor, Ruiz Espinosa, Jesboc A. Mendoza Ortega

  • Abstract

    The study of Thermally Induced Aggregates (TIA) has been explored by analytical techniques due to the influence of variables such as cutting time, curd firmness and performance, and functional and sensory characteristics of the finished product. Cow milk (3% fat) was subjected to heat treatment by kinetic pasteurization. Heat treatments were applied at 72 ° and 78 °C with scan times from 10 to 200 s. It was observed that for the different coagulation times, the gel generated with raw milk had the highest force value (kg), followed by generated with unpasteurized milk to 72 ° C and finally over-pasteurization treatment of 78 ° C 15 s. The behavior of the absorbance spectra in the kinetics of pasteurization established that formation magnitudes βLG-κCN complex and βLG- βLG polymer depend on the intensity of the heat treatment. Formation of complex ΒLG-κCN is one of the most important factors causing an increase in rennet coagulation time because their presence decreases the rate of hydrolysis of κCN by steric hindrance at the specific site of action of the enzyme The measurement technique of the coagulation process by FTIR represents a first promising approach for the development of an alternative optical technique to track the changes associated with the enzymatic coagulation of milk and to determine the ideal cutoff of curd.

 

Methodology for the Use and Valorization of Whey

Ogilver Teniza, Myrna Solís, Aida Solís, Héctor S. Luna, Herminia. Pérez, Norberto Manjarrez, José Luis Gil

  • Abstract

    Industry of cheese in Mexico is very important for its volume of production; during the cheese making is obtained the whey as byproduct; it contains proteins, sugars and minerals, important compounds for the human diet. However, such compounds give a high Biological Oxygen Demand value to the cheese factory effluents. Although it nutritional composition this byproduct is not use, and sometimes is discharged to the environment generating contamination problems. In other countries, whey is dehydrated and commercialized to make food and pharmaceutical products. In this research whey was concentrated and dehydrated and used to make Oaxaca type cheese. We found that it could be used less than 10 % of concentrated whey mixed with milk to make Oaxaca type cheese, with a similar yield than using 100 % milk. In other hand 1 % of dehydrated whey was used as substitute of powder milk yielding the same cheese production. We demonstrate that concentrated or dehydrated whey could be used in the cheese plants to make more cheese, avoiding discharging it and contaminating the environment.

 

Analysis of Changes in Envelope Cell of Escherichia Coli Pathogenic After Exposure to Stress Conditions Using FTIR

Ariana Hernández-Ramírez, Raúl J. Delgado-Macuil, Marlon Rojas-Lopez, Abdu Orduña-Díaz

  • Abstract

    Escherichia coli (E. coli) pathogenic strains are causing foodborne illness, which represent a public health threat that must be confronted. Since bacterial cells react to different conditions of stress inducing physiological and structural changes, causing cells death. The aim of this study was to evaluate infrared spectral changes after exposure to different concentrations of detergent, metanol, polimixina B and proteinase K like factors of stress in the cell envelope of E. coli. For detergent, marked changes in profile of band PO2- at 1251-1319 cm-1 were observed. Spectral variations corresponding to E. coli treated with methanol are observed at 1300 and 900 cm-1 and are associated to damage of the wall and cell membrane, when this cell was treatment with polimixina B, shows significant changes in the two sugar bands at 1070 to 1090 and 1030 to 1060 cm-1. Finally, the effects of proteinase K on E. coli are observed mainly in amide I group and amide II groups, at 1800 and 1500 cm-1, belonging to the proteins and peptides, which give us comprehensive information about proteins structure. Infrared results show that is possible to determine the effect of several stress concentrations associated to changes in the infrared absorption bands.

 

Characterization of Adobera Cheese by Texture Profile Analysis and Mid-Infrarred Spectroscopy

José Martín Ruvalcaba Gómez; Raúl Jacobo Delgado Macuil; Héctor Ruiz Espinosa;Valentín López Gayou, María Dolores Méndez Robles

  • Abstract

    Adobera is a fresh cheese from Jalisco, Mexico, with a creamy and crumbly texture that melt upon heating and a distinctive smooth, salty flavor. It exhibits a mild acidity produced by native microflora. Study aims at measuring texture characteristics of commercial Adobera cheeses made with either raw or pasteurized milk by means of a Texture Profile Analysis while evaluating the feasibility of using FTIR and partial least squares (PLS) regression analysis as a predictive tool for these attributes .Results show statistically significant differences (p<0.05) in cohesiveness (0.624 vs 0.497), springiness (0.898 vs 0.757), chewiness (774 vs 587), gumminess (891 vs 712) and resilience (0.260 vs 0.221) between pasteurized or raw Adobera cheeses. No significant differences in hardness (1490 vs 1425) were observed. 

 

Analysis of Changes in Envelope Cell of Escherichia Coli Pathogenic After Exposure to Stress Conditions Using FTIR

Ariana Hernández-Ramírez, Raúl J. Delgado-Macuil, Marlon Rojas-Lopez,Abdu Orduña-Díaz

  • Abstract

    Escherichia coli is an enteric species that distinguish to form part of the normal intestinal flora human, in fact some of these species supplies many health benefits to the host.The aimed of this study was to assess ultra-structural modifications and infrared (IR) spectral changes at different concentrations of stress exposure and to discriminate between injured and noninjured E.coli cells after their exposure to Detergent, methanol, Polymyxin B (PMB) and proteinase K.To determine the influence of several stress conditions on the FT-IR spectra in patogenic E.coli, stationary- phase cells grown in TSB were treated with (i) Detergent, (ii) methanol, (iii) Polymyxin and (iv), proteinase K, in a concentration range of (1-1000μ/ml). All the stress conditions have an effect on the FT-IR spectroscopic profiles, indicating a higher degree of membrane/wall damage or chemical modification after bacterial exposition to them. Nevertheless, it is important to keep in mind that the spectral region that showed the main changes, is in the range from 1200 to 1000 cm-1, which is dominated by the ring vibrations of the functional groups C-O-C and C-O from the carbohydrates of the cell wall; the behavior showed in this region is quite similar when an acid treatment occurs. 

 

Development And Evaluation of A Low Fat Sour Cream Added With Microencapsulated Lactobacillus casei

Beneranda Murúa-Pagola, Rocío Sánchez-Alaníz, Eduardo Castaño-Tostado, Silvia Amaya-Llano

  • Abstract

    Probiotic foods offer health benefits because of their live probiotic bacteria content. Although the number of probiotic bacteria that provides health benefits has not been firmly established, levels between 109 and 109 cfu g-1 have been suggested. Microencapsulation of probiotic bacteria by spray drying is a method to produce a dried powder of bacteria and a carrier, usually a protein and/or a carbohydrate. The aim of this work was to study the effect of the incorporation of microencapsulated probiotics (Lactobacillus casei ATCC334) by means of spray drying within a polymeric matrix containing phosphorylated high amylose maize starch and whey protein concentrate (WPC), on the manufacture and quality of low fat sour cream, survival of probiotic microencapsulated and free cells during storage during 28 days at 4°C and during exposition to simulated gastrointestinal conditions after storage were evaluated. Encapsulated cells maintained a higher viability along the intestinal assay compared with free cells, showing the protective effect of microencapsulation. The developed reduced fat sour cream was found to be a good vehicle for incorporating encapsulated L. casei, allowing probiotic survival in enough number to maintain its effect as probiotic food (at least 106 CFU per gram feed) during 28 storage days at 4 ° C.

 

Scavenging Capacity of Reactive Nitrogen Species of Four Varieties of Maize (Zea mays L.)

Paola Fabila-Garciaa, Octavio-Dublán-Garcíaa, Leobardo M. Gómez-Olivána, Leticia Xochitl López-Martíneza*

  • Abstract

    Nitric oxide (NO.) and peroxynitrite (ONOO-) scavenging ability, total phenolic compounds and anthocyanin of four maize varieties (yellow, red, black and purple) were determined. Total phenolic contents ranged from 10.6 to 72.1 mg/g and total anthocyanins ranged from 0.70 to 44.6 /g of whole grain flour. For varieties examined those that were most abundant in total phenolic compounds were most abundant in anthocyanins. Crude extracts from pigmented maize were higher in scavenger activity (63% for the nitric oxide inhibition and 84% for the peroxynitrite mediated for inhibition of nitrotyrosine formation), compared with extracts of yellow variety. The extract from purple maize showed the highest scavenging potential. The scavenging activity of each extract against nitric oxide are attributable to the phenolic content compounds that possess redox activity, which allows them to act as free radical scavengers. It is likely that anthocyanins react with peroxinitrite by directing the nitration to their own structures and the aglycone structure is the primary determinant for the peroxinitrite scavenging activity. Differences in reactive nitrogen scavenging ability among maize varieties are reported in the present study.Results showed that scavenging capacities could be correlated with total phenolic and/or anthocyanins content.

 

Growth/Survival of Listeria monocytogenes Scott A with Essential Oil Citral and pH in a Gel Model

J. Martínez-García, L. Cira-Chávez, L. and H., Minor-Pérez

  • Abstract

    The objective of this study was to evaluate the effect combined of pH (5, 6 and 7) and citral essential oil (0 ppm, 100 ppm and 200 ppm) in solid conditions (TSA media).Listeria monocytogenes culture was diluted to final concentration of 1x104 cells which were to empty in petri dishes. TSA media was supplemented with 0.6% yeast extract and added with citral essential oil (from a stock solution of 10,000 ppm) in different concentrations: 0 ppm, 250 ppm and 500 ppm. pH initial of TSA media was adjusted with concentrated HCl. All treatments were incubated at 35°C during 24 h.All treatments were incubated at 35°C during 24 h. A significant reduction (100% of inhibition) of Listeria monocytogenes Scott A population was observed at pH 4 with or without citral essential oil. In these experimental conditions bacterial control showed a reduction of 25% with citral essential oil at 500 ppm (pH 5.0). Also in pH 6.0 there was a reduction of Listeria monocytogenes approximately in a 50% in 250 ppm. At pH 7 was 25% of inhibition with 250 ppm and 500 ppm of citral essential oil.The combination of pH 6.0 and pH 7.0 and and citral essential oil can be used as an alternative to improve the inhibition of Listeria monocytogenes in different systems of foods.

 

Study of the Combination of Soybean Oil and Refrigeration Condition on Growth/Survival of Pseudomonas putida ATCC 795

M. Soperanez-Ramírez, J., Martínez-García. , L, N., Rosales-Toledo,, L., Cira-Chávez,  and H., Minor-Pérez

  • Abstract

    In this study was evaluated the effect of combination of soybean oil and refrigeration temperature on growth/survival of Pseudomonas spp. in a model system. Bacteria control were Pseudomonas putida ATCC 795, Pseudomonas fragi ATCC 13221 and Pseudomonas fluorences ATCC 13525.The effect of soybean oil (5%, 25% and 50%) and refrigeration temperature on bacteria control was carried out on agar nutritive (AN). To solubilize the soybean oil was added in the AN, the surfactant Tween 80 (1%). A volume of 100 μL of bacterial control culture was used to obtain 104 cells. These cultures were emptied into Petri dishes. On these plates were added 10 mL of agar nutritive (40°C) for each treatment. Samples were incubated at 5°C for several times and CFU counts were performed. Treatment control consisted of agar nutritive without soybean oil. The study was analyzed for duplicate.Not significant effect (P ≥ 0.05) on the growth/survival due to the concentrations of soybean oil concentrations was observed in all strains. From 144 h of storage at 5°C the strains of Pseudomonas fragi, Pseudomonas fluorescens and Pseudomonas putida show steady growth up to microbial populations on the order of 7 logarithmic cycles. Strains of study showed greater growth in the following order: Pseudomonas fragi > Pseudomonas fluorescens > Pseudomonas putida.

 

Antioxidant Activity and α-glucosidase Inhibitory Potential of Five Varieties of Dry Beans (Phaseolus vulgaris L.)

Claudia Cruz-Rojas, Jennypher Martinez-Dotor, Octavio-Dublan-Garcia, Leticia Xochitl Lopez-Martinez

  • Abstract

    The functional properties of aqueous extract from five cultivars of raw beans (Black, Pinto, Flor de mayo, Bayo and Mayocoba) including scavenging activity toward NO. (nitric oxide) and .O2- (superoxide) and inhibitory effects on α-glucosidase were investigated. The total phenolics content ranged from 4.1 to 7.1 mg/100 g, the anthocyanin content ranged from 0.47 to 2.7 mg/100 g and flavonoids from 4.8 to 11.4 mg/100 g. The crude extracts from black variety were higher in antioxidant activity against nitric oxide, superoxide and α-glucosidase inhibition (59, 37 and 88 % respectively). The antioxidant activity of each extract against NO. and .O2- could be attributable to the phenolic content compounds. The extract form black variety yielded the most effective antioxidant and inhibitory activity. All beans extracts also exhibited α-glucosidase inhibition in a dose-dependent response. The effectiveness in antioxidant activity and inhibition of α-glucosidase correlate with total phenolics content and with the nature of the pigmentation among the varieties of raw beans evaluated suggesting that phenolic compounds may be involved.

 

Control of Listeria monocytogenes in Panela Fresh Cheese Using Recombinant Endolysins

L.A. Ibarra-Sánchez, M.J. Miller, E. Castaño-Tostado, C. Regalado-González, D.J. Pimentel-González, S.L. Amaya-Llano

1

  • Abstract

    Phage-encoded endolysins are recently considered as new biocontrol tools to inhibit pathogens in food. In this work Listeria phage endolysins, LysZ5 and PlyP100, were cloned and overexpressed in Escherichia coli and their antimicrobial activities against L. monocytogenes were evaluated in Panela fresh cheese. Lytic activity of purified endolysins tested against L. innocua was 15.7 U/mg protein for LysZ5, and 13.7 U/mg protein for PlyP100. Both endolysins showed lytic activity against the six strains of Listeria tested. At concentrations tested, the addition of LysZ5 (19 U/g) and PlyP100 (12 U/g) to Panela fresh cheese reduced viable counts of L. monocytogenes in at least 1 Log CFU/g after 21 day storage at 4°C. As far we know, this is the first report of Listeria phage endolysins to control pathogens in Panela fresh cheese at refrigeration temperature. Moreover, LysZ5 and PlyP100 could be useful as biocontrol to reduce Listeria contaminants in Panela fresh cheese.

 

Differential Extraction of the Agave tequilana Weber Blue Fructans

Luis Humberto González Hernández, José Luis Montañez Soto, Martha Alicia Velázquez Machuca, José Venegas González, Nahúm Castellanos Pérez

  • Abstract

    Inulin and fructooligosaccharides are between the main functional ingredients of foods. Inulin acts as soluble dietary fiber, while fructooligosaccharides play the role of prebiotics agents; ie "life promoters”. Both are reserve carbohydrates of the Agave tequilana Weber azul and are stored in the plant stem. They have different average degree of polymerization (ADP) and thus different average molecular weight (AMW), which provides different ethanol solubility. Fructans contained in agave juice were separated into four fractions using ethanol concentrations from 20, 40, 60 and 80% w/w. The fractions obtained were characterized chemically, for it, its content of direct and total reducing sugars, glucose and fructose were determined and then with these data, its AMW and its ADP were estimated. The yields of each fraction were 18.09, 24.34, 46.05 and 10.77 %w/w, respectively; thus achieving the extraction of the 98.68% of total fructans present in the agave juice. The AMW of the fructans contained in each fraction were 4504, 2933, 1699 and 1070 g/Mole; which corresponds to an ADP of 27.80, 18.10, 10.49 and 6.61 units respectively. By mean of differential precipitation with ethanol, four fructan fractions with different physicochemical and functional properties were obtained from stem of Agave tequilana Weber blue.

 

Analysis of Ultrafiltration Process On The Clarification of Purple Cactus Pear (Opuntia ficus-indica) Juice.

Roberto Castro Muñoz, Carlos Orozco Álvarez and Jorge Yáñez Fernández

  • Abstract

    Membrane technology was employed to clarify purple cactus pear juice. Proposed actions were focused in analyze the process viability in terms of productivity (flux permeate of 22.94 L /m2 h), fouling index (61.20 %) and cleaning efficiency (100%) by batch concentration configuration. The juice quality was conserved due to there were no changes on betalains content (66.05 ± 0.87 mg/L) and antioxidant capacity (14.53±0.05 TEAC). On the other hand, there were significant changes on color properties due to was decreased the L, a*, b* and C values by removal of turbidity on the juice. Finally, the hº value was decreased (from 40.76 to 30.37), it, means the redness grade was increased.

 

Phenols and Pigments in Flesh of Pitaya Stenocereus stellatus

María Guadalupe Pérez Loredo, Blanca Estela Barragán Huerta

  • Abstract

    Stenocereus stellatus fruits from Puebla, Mexico with white, yellow, purple and red flesh were analyzed for color parameters; the luminosity of the samples was 12.62–67.29; H° 2.94–84.31 and Chroma 22.12–47.53; white pitaya had the highest brightness and H° values, and yellow more chromaticity while purple and red fruits had similar values. The concentration of total phenols was 372.64–579.99 mg of galic acid per 100 g of pulp dry weight without significant difference. Total betalain content was 106.36–298.86 mg per 100 g of pulp dry weight; red fruits had the highest content. The 4 fruits had different UV-Vis absorption spectra because the presence and kind of betalains which contain every one of them. According with the HPLC analysis, S. stellatus fruits yellow, purple and red contain 7, 8 and 9 betalains respectively, indicating different composition in the type of betalains presents.

 

Nanobiosensor for Detection of Salmonella in Spinach (Spinacia Oleracea) by FTIR Spectroscopy

Authors: Maria Antonieta Rios Corripio, Dr. Marlon Rojas Lopez

  • Abstract

    FTIR spectroscopy has been used to evaluate the concentration of Salmonella in spinach by using nanoparticles funtionalized with specific antibodies. Nanoparticles (AuNP's) were synthesized by chemical reduction method and protein A was used as stabilizing agent. A next conjugate structure was obtained by adding a polyclonal anti-salmonella FITC antibody to give recognition and specificity to the bacteria salmonella. The construction of the conjugated arrangement was proved in samples of water from spinach intentionally contaminated with Salmonella with concentration of 3x105 UFC/ml. FTIR spectra of spinach show characteristic bands associated to the CO, OH and CH bonds, whereas the spectra of AuNP's show peaks at 1589 cm−1 and 1403 cm−1. The spectrum of the conjugate shows the amida I band at 1660 cm-1 which arises from the protein A. The spectrum of the array also shows similar characteristic bands of proteins, (amide I and amide II). After the interaction of the conjugate array (nanobiosensor) with the Salmonella from spinach intentionally contaminated, the antigen-antibody reaction enable the recognition of this pathogenic microorganism.The change of the line shape of the FTIR spectra makes possible the determination of Salmonella. This nanobiosensor could be used as a simple and selective method.

 

Cloning Of The α-Amylase From Bacillus amyloliquefaciens JJC33M (amyJ33), Isolated Of Sugarcane Soil

Juan J. Montor-Antonio; Sandra del Moral

  • Abstract

    Bacillus amyloliquefaciens JJC33M, is a Gram-positive bacterium, which was isolated from the soils cultivated with sugarcane in Papaloapan Basin (Oaxaca, Mexico) and produces an α-amylase (AmiJ33) interesting for the industry. The cloning the gene (amyJ33) that encodes for α-amylase is presented here. Previously, the PCR amplification of amyJ33 was carried out using degenerate oligonucleotides. However, the analysis with similar complete genes indicated that the PCR product not encoding for the complete gene. Recently, we sent to sequence the B. amyloliquefaciens JJC33M genome by Hiseq2000 and 139 contigs were generated. A 1980 bp sequence was founded at contig 68, which was identified like an α-amylase gene. The complete amyJ33 sequence was analyzed by BLASTX. AmyJ33 gene displayed a high identity (99%) with the α-amylase gene from B. siamensis. The PCR amplification of amyJ33 from the putative signal peptide to termination codon was carried out using the oligonucleotides FpBT and RpBT. The PCR product was cloned into plasmid pBAD-TOPO® to transform cells of E. coli TOP10 and to express AmyJ33. Currently, the experiments needed to biochemically characterization are made.

 

Analysis of Changes in Envelope Cell of Escherichia coli Pathogenic After Exposure to Stress Conditions Using FTIR

Ariana Hernández-Ramírez, Raúl J. Delgado-Macuil, Mónica Rosales-Pérez , Abdu Orduña-Díaz

  • Abstract

    Escherichia coli (E. coli) pathogenic strains are causing foodborne illness, which represent a public health threat that must be confronted. Since bacterial cells react to different conditions of stress inducing physiological and structural changes, causing cells death. The aim of this study was to evaluate infrared spectral changes after exposure to different concentrations of detergent, metanol, polimixina B and proteinase K like factors of stress in the cell envelope of E. coli. For detergent, marked changes in profile of band PO2- at 1251-1319 cm-1 were observed. Spectral variations corresponding to E. coli treated with methanol are observed at 1300 and 900 cm-1 and are associated to damage of the wall and cell membrane, when this cell was treatment with polimixina B, shows significant changes in the two sugar bands at 1070 to 1090 and 1030 to 1060 cm-1. Finally, the effects of proteinase K on E. coli are observed mainly in amide I group and amide II groups, at 1800 and 1500 cm-1, belonging to the proteins and peptides, which give us comprehensive information about proteins structure. Infrared results show that is possible to determine the effect of several stress concentrations associated to changes in the infrared absorption bands.

 

Analysis of Changes in Envelope Cell of Escherichia coli Pathogenic After Exposure to Stress Conditions Using FTIR

Ariana Hernández-Ramírez, Raúl J. Delgado-Macuil, Mónica Rosales-Pérez2, Abdu Orduña-Díaz

  • Abstract

    Escherichia coli (E. coli) pathogenic strains are causing foodborne illness, which represent a public health threat that must be confronted. Since bacterial cells react to different conditions of stress inducing physiological and structural changes, causing cells death. The aim of this study was to evaluate infrared spectral changes after exposure to different concentrations of detergent, metanol, polimixina B and proteinase K like factors of stress in the cell envelope of E. coli. For detergent, marked changes in profile of band PO2- at 1251-1319 cm-1 were observed. Spectral variations corresponding to E. coli treated with methanol are observed at 1300 and 900 cm-1 and are associated to damage of the wall and cell membrane, when this cell was treatment with polimixina B, shows significant changes in the two sugar bands at 1070 to 1090 and 1030 to 1060 cm-1. Finally, the effects of proteinase K on E. coli are observed mainly in amide I group and amide II groups, at 1800 and 1500 cm-1, belonging to the proteins and peptides, which give us comprehensive information about proteins structure. Infrared results show that is possible to determine the effect of several stress concentrations associated to changes in the infrared absorption bands.

 

Effect of Fruit Mistletoe (Cladocolea loniceroides) Extract Over Viability of Cell Cultures

María José Serrano-Maldonado, Frida Paredes-Ruíz, Pablo Damián-Matzumura, Teresa García-Gasca and Jorge Soriano-Santos

  • Abstract

    Mistletoe is a tree parasitic plant, its impact is rather negative causing great tree mortality and economic losses around the world. Cladocolea (C.) loniceroides, a Mexican endemic mistletoe represents a serious pest and it has not been studied until today. It was considered useless because of the pruning problem, however previously have been found that fruit aqueous extract of C. loniceroides presents antioxidant activity. Partial phytochemical screening was assessed on a red fruit aqueous extract. Total polyphenols (52.6 ± 1.47 mg GAE/g), flavonoids (0.23 ± 0.003 mg RE/mg), condensed tannins (14.78 ± 0.25 mg CE/g) and alkaloids (69.32 ± 0.9 mg/g) were evaluated by colorimetric methods. Medium lethal concentration (LC50) was determined to ZR75-1, MCF7, MDA-MB-231 as breast cancer cell lines and MCF10A as non-cancerous cell line. In order to evaluate the death of the four cell lines under mistletoe treatment, MCF10A was significantly more resistant to fruit extract (LC50=196.6 μg GAE/mL) than the other cell lines, this cells are roughly, 170% more resistant than MDA-MB-231 (metastatic tissue) with LC50=72.8 μg GAE/mL. The biological activity of the extract is mainly attributed to antioxidant phytochemicals because of their capacity to stopped free radicals produced in chronic diseases such as cancer.

 

Role of Glucose in Cell Surface Hydrophobicity of Lactic Acid Bacteria

Guiomar Melgar Lalanne, Ebner Azuara Nieto, Humberto Hernández Sánchez and Maribel Jiménez Fernández

  • Abstract

    Modifications in the cell surface hydrophobicity of four Streptococcus thermophilus strains: ATCC 19987 (ST1), ATCC 19258 (ST2), BAA-250 (ST3) and BAA-491 (ST4), two Lactobacillus delbrueckii subsp. bulgaricus strains ATCC 11842D (LB1) and BAA-365D (LB3) and one Lactobacillus helveticus strain ATCC 7995 (LB2) under different concentrations of glucose were investigated. ST1, ST2 and ST4 showed a maximum growth at 24 h with 10% of glucose in Eugon broth while LB1, LB2, LB3 and ST2 showed it with 5% of glucose. However, difference in maximum of absorbance was not significantly different (p > 0.05). All strains could growth up to 30 % of glucose. Congo Red Binding (CRB) at different glucose concentrations (0.5, 5.0, 10.0, 15.0 and 30.0 %) was investigated. CRB resulted dependent both from the strain and the glucose concentration. However, no significant differences (p > 0.05) were found at different glucose concentrations. It can be concluded that, although the formation of CRB has a major protein component, it appears that the presence of high glucose concentrations in the media could modify the formation of bindings. Further works will focus on the importance of the presence of carbohydrates in the CSH.

 

Antioxidant Activity Evaluation of Methanol Extracts of Pleurotus ostreatus

Ivette González Palma. Frida Paredes Ruiz. Jennifer López Sánchez. Hector Escalona Buendía1. Gerardo Díaz Godínez. Jorge Soriano Santos.

  • Abstract

    Mushrooms are considered as a source of biological and physiologically active substances. They accumulate a variety of phytochemicals including phenolic compounds. Therefore, much attention has been focused on the use of natural antioxidants from mushrooms to inhibit lipid peroxidation and by scavenging free radicals. The objective of this research was to evaluate the antioxidant activity of mycelium, primordium and fruit body fresh of Pleurotus ostreatus ATCC 32783 of a methanolic extract. The content of total phenolic of mycelium, primordium and fruit body was of 0.21±0.1, 0.680±0.91 and 0.490±0.2 mg GAE/g fresh weight (fw), respectively. The ferric reducing antioxidant power of the fruit body was 6.69 ± 0.34 μM de FeSO4/g fw, following of primordium and mycelium with 4.57±0.15 and 1.48±0.08 μM de FeSO4/g fw, respectively. The chelating activity for mycelium, primordium and fruit body was an EC50 of 175.98, 35.85 and 34.92 mg/mL, respectively. Finally, the best free radical scavenging activity, of DPPH and ABTS radicals, for primordium was EC50=35.83 and 34.36 mg/mL, respectively. The methanol extract of Pleurotus ostreatus ATCC 32783 can donate electrons and also showed chelating metals activity. The antioxidants should be characterized and then used to prevent oxidative damages in human body.

 

Evaluation in vivo of the Probiotic Effect Of Freeze-Dried Yogurt Based On Vegetable Oil, Inulin and Saccharomyces boulardii

Eunice Tranquilino Rodríguez, Héctor Eduardo Martínez Flores, José Octavio Rodiles López, Gustavo V. Barbosa-Cánovas

  • Abstract

    The aim of this study was to formulate a functional freeze-dried yogurt made with inulin, vegetable oil and Saccharomyces boulardii, and evaluate the viability of yeast. The S. boulardii was encapsulated. The products were formulated as follows: F1 = Yogurt + inulin + vegetable oil (Control). F2 = Yogurt + inulin + vegetable oil + S. boulardii free 0.5 %. F3 = Yogurt + inulin + vegetable oil + S. boulardii microencapsulated at 20%. After, the products were freeze-dried. The pH, acidity, color, solubility, humectability and sensory analysis based on hedonic scale was done to the products. The microencapsulation process shown that yeasts decreased 1.59 Log units, which represents 97.42 % of yeast. There were no significant differences (P<0.05) in the viability of S. boulardi between F2 and F1. Instantaneity tests performed on lyophilized powders, show that the samples with particle size of 1-2 mm showed a better wettability (5-13 min) and solubility (78.5-79.5%). Sensory analysis showed no differences in the general acceptance of the products produced, presenting a value near 4 (Good). The viability of S. boulardii is not affected by the process of freeze-drying. In addition, lyophilized powders have good physicochemical properties and are accepted by the panelists.

 

Metabolites Production By Solid State Fermentation From Arnica

Oliva Cruz V, Juan Buenrostro, Blanca E. Hernández, Cristóbal Aguilar, Sergio Huerta, Lilia A. Prado-Barragán,

  • Abstract

    Actually, the production of natural substances for use in the treatment and prevention of diseases is a great challenge for the pharmaceutical and food industries. The arnica (Heterotheca inuloides Cass) is an herbaceous plant. Due to its polyphenols content, it has been attributed biological properties, such as antimicrobial, antioxidant, analgesic and anti-inflammatory. In this research was evaluated the SSF process on phenolic compounds liberation from arnica using the A. niger GH1 strain. Total polyphenols content was expressed as gallic acid equivalents. The use of A. niger GH1 in a SSF process resulted in suitable alternative to obtain bioactive phenolic. Total polyphenols content was increased, reaching a higher value 29.08 mg/100 per gram of dry matter gdm) at 72 h of culture time, corresponding to 38.85 % respect at control. For other hand, extracts showed up to 86 % of DPPH radical inhibition. The arnica extracts obtained from SSF by A. niger GH1 of arnica can be used in further studies to evaluate its application in edible coatings formulations to improve the shelf-life and quality of different fruits.

 

Molecular Identification and Resistance In Vitro to Gastrointestinal Conditions of Leuconostocmesenteroides Isolated from the Agave salmiana sp.

Diana- Castro, Jorge Yáñez

  • Abstract

    The use of probiotics for disease prevention is becoming increasingly popular. For many of the proposed health effects of probiotics microorganisms it desirable that the organism at least transiently colonized the gastrointestinal tract.Actually an important group of probiotics have aconsiderable potential applications for preventive or therapeutic applications (Lactobacillus, Streptococcus and Bifidobacterium).However, probiotic strains traditionally have been isolated of dairy sources but, vegetable sources have not been fully explored. Thus, the aim of this study was to identify by molecular method and to evaluate the viability to the gastrointestinal conditions of Leuconostocmesenteroides strains isolated from the mead of Agave salmiana.The results found in the survival and adhesionof Leuconostocmesenteroides indicatesthat the strain may be considered a potential probiotic, whose specific properties deserve further investigations in vitro and in vivo.

 

Characterization of a Gallibacteriumanatis12656-12 furMutant

Chantes Guerra A., Maldonado Puga S., Negrete Abascal E., Vaca Pacheco S., Vázquez Cruz C., Sánchez Alonso M. P.

  • Abstract

    Different virulence factors have been described in Gallibacteriumanatis, but their molecular regulation and conditions controlling their expression during an infection are unknown. The aim of this work was to obtain and characterize a G. anatis 12656-12 fur mutant in particular checking its importance as regulator of iron acquisition mechanisms and expression of virulence factors. By in silico analysis of the UMN189 genome, primers were designed to amplify the furlocus. Amplified sequence was cloned,sequenced and interrupted with a streptomycin (Sm) cassette, thus pif55 plasmid was constructed. This used to transform G. anatis 12656-12. Transformants were confirmed by PCR and Southern blot; using HindIII and the 2240 pb probe. It were observed two bands (4.2, 6.6 kb, a specific pattern) of furlocuscorresponding to a one copy of fur gen into the wild type (WT) bacterium; and two bands of 5.6, 8 kb in mutants, by the presence of the Sm cassette. Mutants presented 20% of hemolysis higher that the WT suggesting a partial des-repression of gtxA gen.Only few changes in protein patterns were observed from G. anatis WT and mutant, cultures growing in different iron concentrations. Project supported by PAPIIT IN222313 and PAPCA FESI, UNAM.

 

Identification Phenotypic and Genotypic of Lactococcus and Enterococcus Isolated from Dairy Products Processed in Puebla, México

Alvarado, Ma. Gabriela; Borraz, Ma. Del Tránsito; Hernández, Paola; Martínez, V. Miroslava; Ortega, Omar y Montalvo, Claudia.

  • Abstract

    The objective of this study is the identification of Lactococcus and Enterococcus species from dairy products obtained from Chipilo, Puebla. The strains selection was carried out in MRS agar and tested for Gram staining, catalase, carbohydrates fermentation and tolerance to pH (9.2, 9.6). Genotypes of specimens were verified by PCR of r16S DNA for identification of both genera and PCR of gadB gene to strains Lactococcus lactis subsp. lactis. The lactic acid bacteria (LAB) isolated from whey milk and raw cow milk were forty one and three, respectively. The phenotypic characterization shown that 12 strains were gram positive cocci, catalase-negative, glucose and maltose positive; but variability in the fermentation of ribose, fructose, sucrose and xilose was observed. The microorganisms identified for PCR were two strains as Lactococcus lactis subsp. lactis, and eight strains as genus Enterococcus. Lactococcus lactis strains only growth at pH 9.2, while Enterococcus strains showed tolerance at pH 9.2 and 9.6. These isolated strains could be used like starter cultures with potential probiotic activity.

 

Foaming Capacity And Hydrodynamic Radius From Hydrocolloid Mixture Systems Generated From Phaseolus lunatus Protein Hydrolysates And Anionic Gum (Delonix regia).

Luis Jorge Corzo-Rios María Eugenia Jaramillo-Flores, David Abram Betancur-Ancona, Luis Antonio Chel-Guerrero

  • Abstract

    In the formulation of many processed foods besides water, gums and proteins are the major ingredients. The interactions between these biopolymers play an important role in the structure and function of processed foods. The objective of this study was to analyze the influence of the degree of hydrolysis, hydrodynamic radius and hydrolyzate: gum ratio in foaming ability from hydrocolloid mixture systems (HMS). The Phaseolus lunatus protein was hydrolyzed sequentially with pepsin-pancreatin, to obtain two hydrolyzed with 2 (H1) and 8.3% (H2) of hydrolysis degree (2). HMSs were formed from H1 and H2 with carboxymethylated Delonix regia gum (G) for two ratios H: G 10:1 and 10:5. Foaming capacity (FC) and foam stability (FS), the hydrodynamic radius by dynamic light scattering, were determined. These determinations were realized at pH 3. The FC decreased significantly (p <0.05) when HMS was formed with H2, perhaps due to decreases of the free protein in dispersion of HMSs by protein-gum interactions generated. The FS was improvedwhenHMSs were formed with the lowers degrees of hydrolysis and the smaller amount of gum ratio (H: G = 10:1). The particle size was increased with the formation of HMSs for H1 and H2, indicating interaction between the protein and G. FC decreased when HMSs were formed while FS was improved when the degree of hydrolysis was lesser. The decrease in particle size leads to stability of the foam.

 

Rheological Properties of Alginate, Mucilage and Alginate-Mucilage Dispersions

David Simental-Valle, Jorge Yáñez-Fernández, Carmen Núñez-Santiago

  • Abstract

    Rheological properties of alginate (A) with mucilage from Opuntia ficus mucilage (M) addition were evaluated. Dispersions of alginate and mucilage mixtures with different ratios (100%A, 75%A: 25%M, 50%A: 50%M, 25%A: 75%M and 100%M) and different concentrations (1%, 1.5% and 2%) were prepared; these dispersions exhibited a shear-thinning non-Newtonian behavior. Rotational and Oscillatory rheology test shown that the viscous modulus G´´ predominated over storage modulus G´, representing a liquid-like material. In all concentrations, the slopes of G´ and G´´ trend to 2 and 1 respectively as mucilage ratio increased. The data fitted well using the cross model, the parameter η0 shown a reduction as mucilage ratio increased. The addition of mucilage provide a reduction behavior on the rheological magnitudes. This could be due a dilution effect in mucilage dispersions below 3% concentration

 

Protein Hydrolysates From Bayo Bean (Phaseolus vulgaris L.): Antihypertensive And Antioxidant Activity

Tomás Tovar Benítez, Cristian Jiménez Martínez, Gloria Dávila Ortiz

  • Abstract

    The Enzymatic hydrolysis of proteins is an option for obtain bioactive peptides with biological activities in health benefit to our body. The aim of the present study was to evaluate the ACE-inhibitory and antioxidant activity of protein hydrolysates obtained from P. vulgaris L. The protein concentrate was hydrolysed with pepsin-pancreatin (PP) at different reaction times. Thereafter, ACE-inhibitory activity was determined to protein hydrolysates and ultimately, antioxidant activity by ABTS and DPPH decolorization assay, and iron and copper chelating activity were evaluated to the best hydrolyzate with antihypertensive activity. With PP the DH at 30, 60, 90 and 120 min were 19.12, 24.05, 24.37 and 21.66%, respectively. The protein hydrolyzate obtained at 60 min (HP 60) showed the best ACE-inhibitory activity with an IC50 value of 0.47 mg protein/mL. Moreover, antioxidant activity of HP 60 was 2.26 mM TEAC/mg protein and 32.3% in the DPPH decolorization assay. Also, the percentage of iron chelation (84.1%) was higher compared to the 35.2% obtained in the copper chelating activity. The HP 60 could be an alternative to obtain bioactive peptides that can be used as functional food ingredients to develop the prevention and /or treatment of hypertension and diseases caused by oxidative stress.

 

Fungal Spore Production by Solid-State Fermentation on Maize Stalk and Wheat Bran.

M. Rico Alvarado, R. De la Cruz-Quiroz, C.N. Aguilar ,

  • Abstract

    Biological control is a well-known term that defines some kinds of microorganisms named Biological Control Agents (BCA). The genera Trichoderma spp is one of the most studied BCA’s, which is capable to grow and to compete versus a target root phytopathogen. For that reason, we decided to determinate the conditions to increase its spore production using a low cost agroindustrial residues as solid substrate and polyethylene bags as reactor. We proved mixes of maize stalk and wheat bran and 6 different species of Trichoderma, which were Trichoderma spp, T. asperellum, T. asperellum, T. longibranchiatum, T. yunnanense and T. harzianum). Moisture, pH, inoculum and Temperature were tested in a minimum and a maximum level (74-80%, 3.5-7.0, 1x104–3x107, 26.5-30ºC, according to the order) using a Box Hunter design. Under the experimental conditions in the present study, Trichoderma asperellum produced a great quantity of spores (1.23 x 109 s/g DW) at 72h of culture time using preferably maize stalk as substrate. Finally, it is possible to produce high spore’s levels of T. asperellum by solid state fermentation due to its capacity to grow at a normal environmental conditions.

 

The Study Of Shelf Life For Granulated Piloncillo From Sugar Cane In The Huasteca Potosina

Abigail Reyes Munguía, Ariel Vázquez Elorza, José Isabel Martínez Castillo, Karina Velázquez Paulín, Flavio Hernández Hernández

  • Abstract

    The processing of granulated piloncillo from sugar cane presents a number of problems from obtaining raw materials to marketing, different kind of variables and factors technical and include socioeconomics. This research was to evaluate the storage conditions on the stability and shelf life of granulated piloncillo from sugar cane in the Huasteca Potosina. For this study using variables such as humidity (% H), color, Aw, ash, pH, reducing sugars, ° Brix, metal particles, according to the NMX was performed -F-085-SCFI-2004. The granulated piloncillo samples were diluted 1:2. The product of piloncillo file a dry basis moisture 3.87%, pH 6.03, potential redox 156.96 mV, 58.6 °Brix. After six months of storage samples of granulated piloncillo meet microbiological and physicochemical specifications defined in the regulations. The production process of granulated brown sugar from sugar cane in the Huasteca is performed in the traditional manner of producers (indigenous). However, it is essential to establish quality parameters to reach the production of a safe product by security conditions that determine food standards; also establish public policies to improve the admission process of piloncillo.

 

Analysis Of The Influence Of Temperature, Organic And Inorganic Cations On Ftir Spectra Orange Juice

Gisela Clara Hernández, Raúl J. Delgado Macuil, Héctor Ruiz Espinosa, Irving I. Ruiz-López, Abdu Orduña Díaz, Jesboc Mendoza Ortega

  • Abstract

    Orange juice was added with organic and inorganic cations (NaCl, MgCl2, spermine, spermidine and putrescine) also was heat-processed at 30 and 75 °C using a controlling temperature device (Peltier) to inactivate enzyme pectin methylesterase (PME). Spectral changes in the spectra orange juice region between 3000-3800 cm-1 were caused by the addition of NaCl, MgCl2 and polyamines, affecting the region corresponding of OH bonds in the infrared region, causing spectral shifts to low or high frequencies depending on the temperature level and the cation type. For lower temperature treatment is possible observe a valley follow by a peak since the first times in the kinetic, but to high temperature, 75 °C, a peak follow by a valley is present in the first kinetic times and when the treatment times is more than ten minutes. The study by infrared spectroscopy FTIR showed spectral changes in the region of 3000 and 3800 cm-1 associated with the presence of organic and inorganic cations in orange juice subjected to heat treatment.

 

Enzymatic Hydrolysates of Proteins Isolated From Flour Either Grain or Plant Fraction of Amaranth

Alma X. Avila Alejandre, María de Jesús García Gómez

  • Abstract

    The bioactive peptides (BP) have different biological activities such, antihypertensive, antioxidant, etc. In order to research if the amaranth plants, discarded after seed harvest, could be an alternative source of BP, the protein of vegetal fraction of amaranth (VFA) or grain were isolated using isoelectric precipitation, then proteins were hydrolized with Flavourzyme® and the DH% was evaluated and compared between both proteins substrate.

    The most proteins in amaranth grain are albumin and globulins. The SDS-PAGE showed a band, probably albumin 2 present in the FVA too. Under conditions carried out in this work the %DH of VFA proteins was 50% higher than grain proteins and the %DH values was around 20.2 ± 1.3% after 150 min. In previous reports %DH values around 20% was enough to obtain bioactive peptides. For example, the albumin and globulin hydrolisates from amaranth grain (DH values 20% and 8%, respectively, at 180 min of reaction) or the protein of velvet bean (24.78% after 90 min) showed in both cases ACE-I inhibitory activity. Based on the above mentioned, the VFA proteins could be an appropriate source material for obtaining bioactive peptides

 

Lentinula edodes Dedikariotization And Production Of Inter-Generic Hybrids

A. Sánchez-Hernández, G. Valencia Del Toro, H. Leal-Lara, M. E. Garín-Aguilar, R. Villanueva-Arceand R. Ramírez-Carrillo

  • Abstract

    Lentinula edodes is an edible mushroom difficult to cultivate. Long incubation periods are required for substrate invasionbut this could be reduced by genetic improvement. Production of inter-generic hybrids of edible mushroom is restricted due to incompatibility barriers. Dedikaryotization, however, represents an interesting alternative; it allows recovery of both monokaryotic components (neohaplonts) of dikaryotic strains, and pairing neohaplonts from different genera is reported to be possible. By this procedure, new strains can be easily produced, in which the desired characteristics of the original strains are combined. The dedikaryotization method was modified to recover the neohaplonts of three L. edodes strains (L5, L9 and L15); by decreasing blending time (<30 seconds), more neohaplonts were recovered and the mechanical effect resulted to be a very important factor since neohaplonts were recovered in malt extract liquid media. All neohaplonts were classified according to their mating types. Neohaplonts were recovered symmetrically (χ2taste = α 0.01) for all 3 strains. Twelve inter-generic hybrids were produced by mating two neohaplonts of each L. edodes strain with two P. ostreatus neohaplonts in all possible combinations

 

Degradation of Different Carbon Sources by Lactobacillus delbrueckii subsp. bulgaricus

Hernández de la Cruz Abraham, Cruz Pacheco Karina and Durán Páramo Enrique

  • Abstract

    The influence of a variety of prebiotic sugars and basic carbohydrates on the growth of a selection of probiotic bacteria in human’s health has been increasing for the last 20 years. In this research was studied the ability of Lactobacillus delbrueckii subsp. bulgaricus to metabolize inulin and other sugars as glucose, fructose and sucrose, for this purpose were made fermentation kinetics. When fructose was used as a substrate the exponential growth phase was seen to last 8 hours followed by glucose, sucrose and inulin at 10, 11 and 13 hours, respectively. The exponential phase was followed by a stationary phase with a maximum biomass concentration achieved at 3.9x108, 1.09x109, 9.5x108 y 8.2 x108 CFU/mL by fructose, glucose, sucrose and inulin, respectively. After the fermentation kinetics were complete, the substrate concentrations were 0.9, 1, 2.5 and 3 g/L for glucose, sucrose, inulin and fructose, respectively. Specific growth rate (μ) for L. delbrueckii on glucose, sucrose, inulin and fructose was 0.61, h 0.59, 0.5 and 0.48 h-1, and Y x/s was 0.15, 0.13, 0.12 and 0.09 g cell/g subs, severally. Results presented shown that Lactobacillus delbrueckii subsp. bulgaricus was able to degrade the prebiotic inulin.

 

Analysis of Brucella and Salmonella Present in the Milk, Using Infrared Spectroscopy (FTIR).

Pérez Coyotl A., González Quintero M., Castañeda Roldan E., López Gayou V., Delgado Macuil R. Rojas López M., Zaca Moran O. y Orduña Díaz A.

  • Abstract

    Diseases transmitted by food, which are caused by the presence of various pathogenic microorganisms, have had an impact to human health, as well as in the food industry. Because of this reason, practical strategies for determining the presence of this type of contamination in food are required. Particularly farm milk is one of the foods that are most likely to be contaminated if the hygiene conditions are not suitable for handling. This paper presents an analysis of cow milk from farm, which has been intentionally contaminated with the pathogenic microorganisms: Brucella and Salmonella. The analysis of the contaminated samples was carried out using Fourier transformed infrared spectroscopy technique. The infrared absorption spectra show changes in spectral regions corresponding to carbohydrates (900-1100 cm-1) and the region of proteins (1500-1700 cm-1) when the concentration of strain are modify in the milk.

 

Antioxidat Capacity Of Polyphenolics Extracts In Two Mangifera indica Bark varieties

Martha Rosales-Castro, Dulce Carolina Almonte-Flores, Norma Paniagua-Castro

  • Abstract

    Mangifera indica bark (mango), has been studied in Cuba as a therapeutic polyphenolic extract. In Mexico at least six mango varieties are grown. We obtained polyphenolic extracts from two mango bark varieties: manila and Tommy Atkins, collected at INIFAP Cotaxtla Veracruz. Dried and ground bark was extracted with four solvents independently, water, 96% ethanol, ethanol:water 70/30 and ethyl acetate extract obtained by liquid-liquid partition of concentrate aqueous ethanol:water 70/30 extract. Total phenols (TP), flavonoids (F), DPPH EC50, and β-carotene assays were evaluated. A comparison of presence-absence of polyphenolics compounds by HPLC-MS was made. Both varieties have similar concentrations of phenols and flavonoids, the highest concentrations were obtained with the ethyl acetate solvent. In antioxidant capacity by DPPH, ethanol 96% extract had the best capacity in Manila variety, while in Tommy Atkins was ethanol 70% extract. The β-carotene assay was similar in both. By HPLC-MS assay similarities in the presence or absence of compounds were found. Mangiferin (MW 422 Da) is the main compound in both varieties. Evidence of mangiferin gallate (MW 574 Da) and type catechin (flavan-3-ol) flavonoids were found.

 

Characterization of Populations of Lactic Acid Bacteria by Specific Amplification of 16s Ribosomal DNA

María de Jesús García, Sandra del Moral, Karin Navarro, Oscar Nuñez, Laura Ramírez.

  • Abstract

    The use of selected starters in large-scale industrial processes is causing a continuous decrease in natural microbial biodiversity. Traditional dairy products from unselected microflora and non-pasteurized milk are still the source of unknown strains that could be used to differentiate dairy products. The natural association of micro-organisms in regional cheese from raw bovine milk made in Papaloapan river basin no have been investigated, thus the aim of this work was examined the dominant microflora involved in natural whey cultures using the sequence of 16S rDNA for taxonomic identification.

    The application of molecular techniques has allowed the selection of strains of lactic acid bacteria, from complex microbial communities. In this work a total of 19 strains were isolated from whey fermented and they were identified by molecular methods. Analysis of 16S rDNA demonstrated that the isolated strains resulted predominantly in Lactobacillus (55%), followed by Enterococcus (30%) and finally Streptococcus (15%). All these strains could have a positive influence on artisan regional cheeses produced from raw milk, or whey starter cultures.

 

Effect of Temperature and pH on the Antioxidant Activity of Protein Hydrolysates as Obtained of Amaranthus hypochondriacus L. Grain

López Sánchez J., Paredes F.M.H., Palma I., Soriano Santos J.

  • Abstract

    The study on the stability of peptides during processing and the effects on their bioactivity are crucial issues, therefore the main objective of this essay was evaluate the effect of temperature and pH on the chelating activity of Cu2+ and Fe2+ on hydrolysates of globulin. Chelating activity on Cu2+ was lower than that exhibited by Fe2+. Effects of different temperatures (40 to 120°) on chelating Cu2+ activity of globulin hydrolysates there were no significant differences (p <0.05). All globulin hydrolysates at acidic pH showed a decrease on the Cu2+ chelating activity but at alkaline pH this activity was kept constant. Regarding Fe2+ chelation activity decreases when temperature was increased at 80° C; the EC50 observed was 479±.01 μg/mL, while at 120 °C the EC50 was 800±.05 μg/mL. Concerning the effect of pH was observed at alkaline pH chelating activity was stable the EC50 observed was 11±.09 μg/mL. Globulin hydrolysates were stable at different temperatures assayed as well as at different pH (6-12). Thus the globulin hydrolysates are commercially attractive as ‘health enhancing ingredient’ in the functional foods design. However, assessments for toxicity are necessary before its use.

 

Partial Characterization of Antilisterial Activity Produced by two Lactic-Acid Bacterium Strains

J.C. Ramírez-Palacios, J. Zapata-Lara, M.R. López-Cuellar, A.I. Rodríguez-Hernández, N. Chavarría-Hernández

  • Abstract

    Bacteriocins are ribosomally-sinthesized peptides mainly from lactic-acid bacteria (LAB), showing antimicrobial activity against related microorganisms. Most LAB bacteriocins are non-toxic to eukaryotic cells and are generally recognized as safe (GRAS). These peptides have attracted considerable interest given their potential to be used in food preservation and health care applications. The aim of this study was to identify and partially purify bacteriocin type substances (PPB) produced by Enterococcus faeciumand Streptococcus infantarius.Bothstrains were cultured in MRS medium at 35°C for 24 h. The PPB were obtained by centrifugation (cell- free supernatant) and adjusted pH to 6.5. The cell-free supernatant was concentrated and pasteurized (110ºC, 10min). A two-fold dilution series of PPB were prepared to check the activity against Listeria monocytogenes as indicator, using a commercial bacteriocin (Nisin) as a reference. The antilisterial activity were 13,900 and 3,200 AU/mL for S. infantarius and E. faecium, respectively (also equivalent to 44,200 and 437 mg nisin/mL, respectively). Nowadays there are no reports about bacteriocins produced by S. infantarius. Further studies must be done to fully characterize these bacteriocins.

 

Effect of Microencapsulation on Viability of Probiotic Exposed to Simulated Gastrointestinal Conditions

Paola Hernández-Carranza, Virginia Flores-García , Ma. Lorena Luna-Guevara, Irving I. Ruiz-López, Galdy Hernández Zarate , Carlos E. Ochoa-Velasco.

  • Abstract

    Microencapsulation technologies maintained viable probiotic bacteria during passage through the gastrointestinal tract, recently, the agave juice is used as prebiotic due selectively stimulated the growth and/or activity of bacterial in the colon. In this work two species of Lactobacillus were encapsulated by ionic gelation using agave juice obtained from Tlaxcala, Mexico and exposed to gastric and intestinal fluids, to evaluate the survival of Lactobacillus. The agave juice used in ionic gelation acted as prebiotic due to the presence of fructans. Lactobacillus rhamnosus was less resistant to gastric and intestinal juices. It´s important to evaluate the survival of probiotic strains for use in foods and the creation of functional foods

 

FTIR Analysis Of Aluminum Concentration In Carmine Production

Edith Cortés R., Lilia Tapia L., M. Guadalupe García M., Erik Ocaranza S.

  • Abstract

    The current food industry have a great demand for safe natural pigments to replacing the use of synthetic colorants. Natural sources may be vegetable or animal origin such as carminic acid extracted from the cochineal (Dactylopius coccus Costa). Carminic acid may change from red to violet by pH variations and could be stabilized by metal complexation. The carmine is a common pigment used in cosmetics and food produced by carminic acid complexation with calcium-aluminic salts. However, recently it has been linked to aluminum as a risk factor for Alzheimer´s syndrome, being necessary develop techniques to determine the metal content in the product.In this work carmine pigments with different aluminum content were formulated and analyzed by Fourier Transform Infrared Spectroscopy (FTIR), in order to identify and quantify the aluminum complex associated bands in the FTIR spectra.Any aluminum compounds exclusive peak could not be found in FTIR spectra. However, was found correlation between some spectrum areas with the concentration of aluminum in the pigment, so that a technique is established to determinate the aluminum content in carmine by FTIR analysis.

 

Antioxidant Activity of Some Medicinal Plants Determined By FTIR Spectroscopy and Multivariate Analysis

J. E. Cruz-Espinoza, A. Orduña-Díaz1, O. Zaca-Moran, R. Delgado-Macuil, V.L. Gayou M. Rosales-Pérez, M. Rojas-López

  • Abstract

    A large number of medicinal plants and their purified constituents have shown beneficial therapeutic potentials. The majority of the antioxidant activity is due to flavonoids, flavones, isoflavones, anthocyanin, coumarin lignans, catechins and isocatechins. Commonly colorimetric methods are used to evaluate antioxidant activity in extracts of plants. However other alternative method that employs Fourier transform infrared spectroscopy (FTIR) and statistical strategies known as multivariate analysis can be applied. Leaves of eight medicinal plants were selected for this study (Moringa oleifera, Laurus nobilis, Sambucus nigra,Mentha spicata, Menta piperita, Persea americana, Origanum vulgare, and Sambucus nigra), obtained a chemometric method that predicts quantitatively antioxidant activity of extracts of these medicinal plants without the use of reagents.

 

Stevioside And Rebaudioside Extraction By Non-Conventional Techniques

Victor G. Canuas-Landero, Lluvia Rodriguez, Saúl Ramírez, Sandra L. Cabrera-Hilerio, Gabriel Ríos-Cortés, Alma L. Martínez, Joel Reyes, Minerva Rosas-Morales, Ada Ma. Ríos-Cortés.

  • Abstract

    Stevioside and rebaudioside A, diterpene glycosides, are gaining an increasing interest because of their sweetness taste, non-caloric characteristic, and medical properties. New non-conventional extractions techniques have been used instead of classical extractions with chemical methods due to high yields, rate extraction, and high efficiency on the use of solvents. Enzymatic assisted extraction, ultrasound-assisted extraction, and ultrasound-assisted enzymatic extraction were evaluated as non-conventional extraction methods under similar condition and same enzymes as well. All the extractions showed a similar behaviour with the yields of stevioside and rebaudioside A. The concentration of rebaudioside A was found 75% upper than that of stevioside which is favourable because rebaudioside A has more commercial interest.

 

Allele Frequencies of Four Molecular Markers Associated With Fatty Acid Composition in Mexican Beef

Deysi Hernández Antonio, Williams Arellano Vera, María Salud Rubio Lozano, Víctor Ricardo Moreno, Gaspar Manuel Parra Bracamonte and Ana María Sifuentes Rincon

  • Abstract

    Here we determine allele frequencies of four molecular markers associated with health index (HI) and the synthesis of fatty acids (FA) 205 samples of beef Mexican cattle. Markers analyzed were: rs109937152 C/T Steroil Co-A Desaturase 5, rs110036978 C/G Receptor Recognition Particle Signal, and rs134478878 C/G and rs133396141 C/T both of Gene Induced Insulin 2. We found that for those markers previously associated with increased IS and content of MUFA, MCFA, LCFA allelic frequencies were moderated for the favorable allele C (0.73 and 0.59 for rs109937152 and rs110036978 C/G, respectively). For markers rs134478878 C / G and rs133396141 C/T the favorable alleles were the most frequent allele G (0.93) and allele T (0.94). These alleles, had been associated with decreased IS, and increased AGS and SCFA. The results show a higher frequency of unfavorable allelic variants, however despite the negative results found, could be implemented molecular strategies focused on increasing the favorable allelic variants in the Mexican beef cattle, which would generate meat products with added value and a better impact on the health of consumers.

 

Evolutionary Polymorphisms in Hexose Transporters (HXT1 Y HXT3) Are Related to Biotechnological Origin in Industrial Saccharomyces Cerevisiae Isolates

M. C. Tamayo Ordoñez, S. Ramírez-González, C.P. Larralde-Corona,J. A. Narváez-Zapata

 

  • Abstract

    Continue improvement applied on fermentative Agave process is a desirable goal. Tamaulipas Mezcal production is still a non-standardized process due mainly to lack information on associated microbial community that occurs in these must. Yeast inhabiting this environment must face high osmotic sugar amounts (up 200g/L) characterized by high fructose content (up 90%). Therefore, it is probable detect a differential evolutionary process in some important fructose associated genes. Hexose transporters (HXT1 or HXT3) activity has been related with changes in fructose consumption and diverse polymorphisms of these genes has been previously proposed as implied in this fructose preference. However, so far, there a not a systematic study focused on polymorphic HXT changes of according yeast isolate origin or fructose consumption behavior. Anterior, it is even more important in Agave must by their specific sugar characteristics. The aim of this study was characterize the full polymorphism changes on HXT1 or HXT3 in different Saccharomyces cerevisiae isolates obtained from Mezcal must. The results indicated the presence of specific HXT1 and HXT3 haplotypes occurrence in Mezcal must strains, suggested a probably adaptation of these hexose transporters of according to high fructose concentrations that occurs in these Agave must.