جستجوی مقالات مرتبط با کلیدواژه "اسید لاکتیک باکتری ها" در نشریات گروه "صنایع غذایی"

The aim of this study was to identify the lactic acid of the dominant bacteria in pickled garlic, using initial biochemical tests and PCR technique and to investigate their potential probiotic potential. For this purpose, to determine the probiotic potential of these isolates, some confirmatory tests including resistance to acid, resistance to simulated gastric conditions, resistance to bile salts, activity against pathogenic bacteria, susceptibility to some common antibiotics and hemolytic activity of isolates were performed. Based on BLAST results, five isolates of Lactobacillus plantarum, two isolates as Pediococcus ethanolidurans and one isolate as Lactobacillus brevis were identified. The lactic acid bacteria isolated in this study had the ability to survive at pH 2.5, grow in medium containing 0.3% bile salt, were sensitive to antibiotics and lacked hemolytic activity and therefore have probiotic properties. Supernatant of isolates of this study in high concentrations had the ability to inhibit growth of pathogenic bacteria and the lethal activity against them. Finally, the isolates of this study can be added to other products in the future as a strain with probiotic potential.

Fungal spoilage plays an essential role in the deterioration of food and in the creation of foodborne disease. In addition, the production of various mycotoxins by fungi can cause serious dangers such as carcinogenic, teratogenic, immunotoxic, neuromastoxic, toxic dead, mycotoxicosis and Kashin Beck disease. On the other hand, despite the increasing resistance of molds to synthetic preservatives, that may produce carcinogenic nitrosamine, no effective strategy has been proposed to safely reduce of microbial growth for public health. Therefore, due to the safe and probiotic properties of the lactic acid bacteria that have been approved (GRAS and QPS), can be used as natural preservatives to prevent fungal spoilage of food. The ability to prevent and inhibitory fungal spoilage by lactic acid bacteria is mainly due to the production of antimicrobial compounds such as organic acids, fatty acids, hydrogen peroxide, phenyllactic acid, cyclic delpeptide, proteinaceous compounds, diacetyl, bacteriocin and reuterin. Also, the most important inhibitory mechanisms of lactic acid bacteria against fungal corruption include membrane  destabilization, proton  gradient interference,  enzyme  inhibition,  and  creation  of  reactive  oxygen  species. Therefore, in this paper, it has been tried to overview of antifungal metabolites and their chemical structure, inhibitory mechanisms and probiotic properties of the lactic acid bacteria.

Human breast milk is known to be the best food for rapidly growing infant scince breastfeeding protects the newborn against some diesease such as infection disease،asthma and allergy. This effect may be due to the useful and natural microflora of breast milk which could be depending on diets of mothers. For the first time، this study accomplished to evaluate microflora of mother’s breast milk along with sepration and identification of local bacteria that could be as a candidat for bacteriotherapy and possessing probiotic propertiesin Iran. In this study،309 different colonies were isolated from 20 breast milk samplesof mothers who were registered in Mshhad. The isolated were selected based on the results of catalase test، gram stain، and bacterial morphology. The results showed that 40 out of 309 selected bacteria were catalase negative and gram positive stain. The whole genomes of 16s ribosomal DNA of isolated colonies were amplified using polymerase chain reaction for identification down to the strain level. According to the results، the breast milk contains various species of enterococci، Streptococci، Staphylococci and Lactobacilli. The most abundant bacteria، enterococcus faeciumwasisolated from 50% of samples representing 47. 5% of the total isolated bacteria. Generally 10 and 27. 5 percentage of isolated bacteria were La. rhamnosusLc 705and Streptococcus salivarius، respectively، that were isolated from 20 and 35 percent of milk samples،respectively.