Screening and kinetics of glutaminase and glutamate decarboxylase producing lactic acid bacteria from fermented Thai foods

L-glutaminase and glutamic acid decarboxylase (GAD) catalyzes the hydrolysis of L-glutamine and glutamate, respectively. L-glutaminase widely used in cancer therapy along with a combination of other enzymes and most importantly these enzymes were used in food industries, as a major catalyst of bioconversion. The current investigation was aimed to screen and select L-glutaminase, and GAD producing lactic acid bacteria (LAB). A total of 338 LAB were isolated from fermented meat, fermented fish, fermented soya bean, fermented vegetables and fruits. Among 338 isolates, 22 and 237 LAB has been found to be positive for L-glutaminase and GAD, respectively. We found that 30 days of incubation at 35 ºC and pH 6.0 was the optimum condition for glutaminase activity by G507/1. G254/2 was found to be the best for GAD activity with the optimum condition of pH 6.5, temperature 40 ºC and ten days of incubation. These LAB strains, G507/1 and G254/2, were identified as close relative of Lactobacillus brevis ATCC 14869 and Lactobacillus fermentum NBRC 3956, respectively by 16S rRNA sequencing. Further, improvements in up-stream of the fermentation process with these LAB strains are currently under development.

Use of starter cultures isolated from native microbiota of artisanal sausage in the production of Italian sausage

The most promising microorganisms for use as starter cultures are those isolated from the native microbiota of traditional fermented products. The aim of this study was to evaluate the use of lactic acid bacteria selected from the native microbiota of sausages produced by spontaneous fermentation as starter cultures for the production of sausage. Strains of Lactobacillus plantarum 503 and 341 have the potential for use as starter cultures in the manufacture of Italian sausage type. The population of lactic acid bacteria in sausages was >8 log CFU.g-1 during fermentation, which caused the pH to decrease to <4.5. This decrease in pH and the water activity of < 0.90 of sausages ensures the safety and preservation of this product. Sausages produced with these lactic cultures fulfill the requirements for microbiological quality and composition of Italian sausage type. Our results suggest the possibility of using these starter cultures for the production of sausages with peculiar characteristics that contribute to the identity of the product.

Colorimetric and sensory characteristics of fermented cured sausage with Brazilian ostrich meat addition

The aim of this study was to determine the colorimetric and sensory characteristics of a fermented cured sausage containing ostrich meat (Struthio camelus) and pork meat. Four treatments were performed: one with no ostrich meat (TC) and the others containing 19.08 (T1), 38.34 (T2), and 57.60% (T3) of ostrich meat and pork meat. Colorimetric analyses were measuring L*, a*, b*, C*, and hº. Sensory analysis was conducted assessing color, aroma, flavor, and texture at the end of the sausages' processing. The sausages containing ostrich meat were statistically different from the control in the instrumental colorimetric analysis. In the sensory analysis, no significant differences were observed between the treatments for aroma, flavor, and texture. However, significant differences were found in the color of the sausages due to the high myoglobin content present in the ostrich meat, which resulted in a very dark color in the treatment with the highest percentage of this type of meat.

Nutritional value and fatty acid composition of some traditional Argentinean meat sausages

The aim of this study was to determine the nutritional composition (moisture, protein, carbohydrates, and total fat) of some meat products produced in the northeastern Argentina, analyzing fatty acids composition, polyunsaturated/saturated fatty acid ratio PUFA/SFA ratio (polyunsaturated/ saturated fatty acids), n-6/n-3 ratio, and CLA (conjugated linoleic acid) content. Thirty traditional meat products produced by different processes were used. The samples were classified into 4 different categories as follows: salamín (dry cured and fermented sausage), chorizos (raw sausage), chorizo ahumado (cooked and smoked sausage), and morcilla (cooked sausage). From the results obtained it can be said that the total carbohydrate contents of the salamín studied were slightly lower; fat content of raw chorizo was significantly lower, and protein content of chorizo ahumado was significantly higher than those comparison from databases from other regions of Argentina, USA, and Spain. Except for chorizo, which has a value lower than 0.4, the PUFA/SFA-stearic ratio of the other products were a little higher than those reported by other researchers. CLA (Conjugated linoleic acid) contents between 0.03% and 0.19% were detected. The results obtained indicate that salamín produced in northeastern Argentina, Chaco state, shows high protein and PUFA (Polyunsaturated fatty acids) contents, and low atherogenic and thrombogenic indexes, which makes it a more healthful product than those of similar composition produced in other countries.

Polymerase chain reaction (PCR) for the detection of Salmonella in artificially inoculated chicken meat

The aim of this study was to develop a polymerase chain reaction (PCR) protocol for the detection of Salmonella in artificially contaminated chicken meat. Tests were performed with different dilutions of Salmonella Typhimurium or Salmonella Enteritidis cells (10-7, 10-8 or 10-9 CFU/mL) inoculated in chicken meat samples, in order to establish the limits of detection, incubation times (0, 6, 8 and 24 hours of pre-enrichment in PBW 1%) and three DNA extraction protocols (phenol-chloroform, thermal treatment and thermal treatment and Sephaglass). The assay was able to detect until 10-9 CFU/mL of initial dilution of Salmonella cells inoculated in chicken meat, which allows detection of Salmonella within 48 hours, including 24 hours of pre-enrichment and using the phenol-chloroform DNA extraction protocol. As the results are obtained in a shorter time period than that of microbiological culture, this procedure will be useful in the methodology for detection of Salmonella in chicken.

SURVIVAL CAPACITY OF Arcobacter butzleri INOCULATED IN POULTRY MEAT AT TWO DIFFERENT REFRIGERATION TEMPERATURES

Arcobacter spp. are emerging enteropathogens and potential zoonotic agents that can be transmitted by food and water, being considered a public health risk. The high isolation rate of these bacteria from poultry products suggests that it may be a major source of human infections. One hallmark for differentiating the genus Arcobacter fromCampylobacter includes their growing capacity at low temperatures (15-30 °C) under aerobic conditions. However, little is known about the population density variation of these bacteria at different refrigeration temperatures. The aim of this study was to determine the survival behavior of two different Arcobacter butzleri concentrations (104 CFU/mL and 107 CFU/mL) inoculated on chicken legs and held at two different refrigeration temperatures (4 and 10 °C) throughout storage time. Results have shown that A. butzleri had growing capacity both at 4 and 10 °C. No statistical difference between the survival trends was found for both bacterial concentrations and temperatures tested. This study shows that A. butzleri is a robust species with regard to storage temperature, and represents a potential health risk for poultry meat consumers.

Effects of a novel fermented soy product on the serum lipids of hypercholesterolemic rabbits

OBJECTIVE: To assess the effect of a new feed soy product fermented by Enterococcus faecium and Lactobacillus jugurti on the serum lipid levels of rabbits with induced hypercholesterolemia. METHODS: Thirty-two rabbits were divided into 4 groups as follows: 1) control (C); 2) hypercholesterolemic (H); 3) hypercholesterolemic + fermented product (HPF); and 4) control + fermented product (CPF). The H and HPF groups were fed with a diet with 0.15% (p/p) cholesterol in the first 15 days. C and CPF groups received regular food preparation. The HPF and CPF groups received 10 mL daily of the fermented 30 days. Blood samples were drawn at the beginning of the study and at the 15th and 30th days. Concentrations of total cholesterol, HDL-cholesterol, and triglycerides were analyzed. RESULTS: After 15 days, the HPF group showed a total cholesterol concentration lower (18.4%) than that of the H group (p=0.05), but this difference disappeared after 30 days. No change was observed in total cholesterol levels of C and CPF groups. After 15 days, the HDL-cholesterol was higher (17.8%) in the HPF group, but the triglyceride levels remained unchanged in all groups during the same period of time. CONCLUSION: The soy fermented product caused an 18.4% reduction in total cholesterol and a 17.8% increase in the HDL-fraction. It may, therefore, be a possible coadjutor in the treatment of hypercholesterolemia.

O farelinho de trigo fermentado com Bacta-Mon e excremento de vaca na alimentação de pintos

Bacta-mon, produced by Bacta-mon S. A., São Paulo, Brazil, is recommended as a microbiological, and suggested as a supplement for animal rations. This experiment deals with this product in chicken feeding. Four lots of baby chicken received, during 6 weeks the following treatments: a control ration Rl; a ration R2 containing 10 per cent of wheat standard middlings fermented by Bacta-mon, substituting equal weight of wheat standard middlings of the control ration Rl; two rations R3 and R4, both without meat meal and containing 10 per cent of wheat standard middlings fermented respectively by Bactamon and fresh cow manure, substituting equal weight of wheat standard middlings of the control. The results may be so summarized: (1) On the basis of the weights of the chicks at 6 weeks age, we concluded that there was not any advantage in the addition of the wheat standard middlings fermented by Bacta-mon. (2) The rations R3 and R4 were considered statistically equivalents and lower the control ration Rl. (3) It seems that the main difference observed in these results may be atributed to lack of animal protein. (4) The highest mortality and the lowest consumption of feed by the lots receiving ration R3 and R4, seem to indicate, in addition, that this prejudice was due the lack of animal protein and the unpalatability of these rations.

Antimicrobial resistance profiles of enterococci isolated from poultry meat and pasteurized milk in Rio de Janeiro, Brazil

The enterococci are important nosocomial pathogens with a remarkable capacity of expressing resistance to several antimicrobial agents. Their ubiquitous nature and resistance to adverse environmental conditions take account for their ability to colonize different habitats and for their potential for easy spreading through the food chain. In the present study we evaluated the distribution of species and antimicrobial susceptibility among enterococcal isolates recovered from food obtained in retail stores in Rio de Janeiro, Brazil. The following species were identified among 167 isolates obtained from poultry meat and 127 from pasteurized milk: Enterococcus faecalis (62.6%), E. casseliflavus (17.3%), E. durans (6.5%), E. gallinarum (3.0%), E. gilvus (2.4%), E. faecium (2.0%), E. hirae (1.4%), and E. sulfureus (1.0%). The overall percentages of antimicrobial resistant isolates were: 31.2 % to tetracycline, 23.8% to erythromycin, 11.3% to streptomycin, 4.3% to chloramphenicol, 3.9% to gentamicin, 1.4% to norfloxacin, 1.1% to imipenem, 0.7% to ciprofloxacin, nitrofurantoin, and penicillin, and 0.4% to ampicillin. Intermediate resistance was detected in frequencies varying from 0.5% for linezolid to 58.2% for erythromycin. None of the isolates showed resistance to glycopeptides. High-level resistance to aminoglycosides was observed in 13.1% of the isolates. Multiresistance was observed in E. faecalis, E. casseliflavus, E. faecium, E. gallinarum, E. durans and E. gilvus.

Armadillo meat intake was not associated with leprosy in a case control study, Curitiba (Brazil)

Leprosy's progression and its maintained endemic status, despite the availability of effective treatments, are not fully understood and recent studies have highlighted the possibility of involved Mycobacterium leprae ambient reservoirs. Wild armadillos can carry leprosy and, because their meat is eaten by humans, development of the disease among armadillo meat consumers has been investigated. This study evaluated the frequency of armadillo meat intake among leprosy patients as well as age and gender matched controls with other skin diseases from a dermatological unit. Armadillo meat consumption among both groups was adjusted by demographic and socioeconomic covariates based on a conditional multiple logistic regression model. One hundred twenty-one cases and 242 controls were evaluated; they differed in socioeconomic variables such as family income, hometown population and access to treated water. The multivariate analysis did not show an association between the intake of armadillo meat and leprosy (odds ratio = 1.07; CI 95% 0.56-2.04), even when only cases with no known contacts were analyzed. We conclude that leprosy is not associated with the intake of armadillo meat in these patients.

Widespread distribution of CTX-M and plasmid-mediated AmpC β-lactamases in Escherichia coli from Brazilian chicken meat

The dissemination of plasmid-mediated antimicrobial resistance genes may pose a substantial public health risk. In the present work, the occurrences ofblaCTX-M and plasmid-mediated ampCand qnrgenes were investigated in Escherichia colifrom 16 chicken carcasses produced by four commercial brands in Brazil. Of the brands tested, three were exporters, including one of organic chicken. Our study assessed 136 E. coli isolates that were grouped into 77 distinct biotypes defined by their origin, resistance profiling, the presence of β-lactamase and plasmid-mediated quinolone resistance genes and enterobacterial repetitive intergenic consensus-polimerase chain reaction typing. TheblaCTX-M-15, blaCTX-M-2 andblaCTX-M-8 genes were detected in one, 17 and eight different biotypes, respectively (45 isolates). Twenty-one biotypes (46 isolates) harboured blaCMY-2.Additionally, blaCMY-2 was identified in isolates that also carried either blaCTX-M-2 orblaCTX-M-8. The qnrB and/orqnrS genes occurred in isolates carrying each of the four types of β-lactamase determinants detected and also in oxyimino-cephalosporin-susceptible strains. Plasmid-mediated extended-spectrum β-lactamase (ESBL) and AmpC determinants were identified in carcasses from the four brands tested. Notably, this is the first description ofblaCTX-M-15 genes in meat or food-producing animals from South America. The blaCTX-M-8, blaCTX-M-15 andblaCMY-2 genes were transferable in conjugation experiments. The findings of the present study indicate that plasmid-mediated ESBL and AmpC-encoding genes are widely distributed in Brazilian chicken meat.

Genetic polymorphisms related to meat traits in purebred and crossbred Nelore cattle

The objective of this work was to estimate the allelic and genotypic frequencies of CAST/XmnI, a calpastatin gene polymorphism, and CAPN530, a calpain 1 large subunit gene polymorphism, in different beef genetic groups (Nelore and Nelore x Bos taurus), and to investigate associations between these polymorphisms and carcass and meat traits. Three hundred animals - comprising 114 Nelore, 67 Angus x Nelore, 44 Rubia Gallega x Nelore, 41 Canchim, 19 Brangus three-way cross and 15 Braunvieh three-way cross- were genotyped by PCR-RFLP and phenotyped for rib-eye area (REA), back-fat thickness (BT), intramuscular fat (IF), shear force (SF) and myofibrillar fragmentation index (MFI). The occurrence of the two alleles of the CAST/XmnI and CAPN530 single nucleotide polymorphisms (SNPs) in a B. indicus breed, which permitted association studies in purebred and crossbred Nelore cattle, was first shown in the present work. No relationship was found between the CAST or CAPN1 SNPs and growth-related traits (REA) or fat deposition (BT and IF), since calpastatin and µ-calpain are not physiologically involved with these traits. Moreover, the association results between genotypes and aged meat tenderness (assessed by SF and MFI) showed that these markers are useless in assisted selection for purebred Nelore and their crosses with B. taurus.

Candidate SNPs for carcass and meat traits in Nelore animals and in their crosses with Bos taurus

The objective of this work was to evaluate the effects of single-nucleotide polymorphisms (SNPs) in the genes IGF1 (AF_017143.1:g.198C>T), MSTN (AF_320998.1:g.433C>A), MYOD1 (NC_007313:g.1274A>G) and MYF5 (NC_007303:g.1911A>G) on carcass and meat traits in Nelore (Bos indicus) and Nelore x B. taurus. A total of 300 animals were genotyped and phenotyped for rib eye area (REA), backfat thickness (BT), intramuscular fat (IF), shear force (SF) and myofibrillar fragmentation index (MFI). The effects of allele substitution for each SNP were estimated by regression of the evaluated phenotypes on the number of copies of a particular allele using the general linear model. The polymorphism at IGF1 was non-informative in Nelore animals. In crossbred animals, the IGF1 C allele was associated with greater REA. However, this relation was not significant after Bonferroni correction for multiple testing. The A allele of the MSTN polymorphism was absent in Nelore cattle and was only found in two crossbred animals. The polymorphisms of MYOD1 and MYF5 were little informative in Nelore animals with G allele frequency of 0.097 and A allele frequency of 0.031, respectively. These markers show no association with the analyzed traits in the total sample of evaluated animals.

Meat lipid profile of steers finished in pearl millet pasture with different rates of concentrate

The objective of this work was to evaluate the meat lipid profile from Devon beef steers finished in pearl millet (Pennisetum americanum) pasture and fed at different rates of concentrate supplementary diet. Twelve steers weighing 270 kg, at 12‑month‑average initial age, were randomly distributed into three treatments: pearl millet pasture; and pearl millet pasture plus a concentrate equivalent at 0.5 or 1.0% of body weight, with two replicates. Total contents of saturated and unsaturated fatty acids, the polyunsaturated:saturated ratio and other relevant fatty acids as the vaccenic acid, conjugated linoleic acid, omega‑3, and omega‑6 were not affected by the consumption of a concentrate supplement at 0.5 or 1.0% live weight. However, the 0.5% supplementation level reduced the concentration of dihomo‑γ‑linolenic fatty acid (C20: 3 n‑6), while the 1.0% supplementation level elevated the content of docosahexaenoic (DHA) (C22: 6 n‑3) fatty acid, and the omega‑6:omega‑3 ratio in meat. Consumption of up to 1.0% energy supplementation increases the omega‑6:omega‑3 ratio in meat from Devon steers grazing on pearl millet pasture.