Multilocus genotyping for classification and genetic structuring of Lactobacillus casei: insights from source and geographical origin.

The aim of the study in this article is to systematise the newly introduced strains of Lactobacillus based on determining the nucleotide sequence of a particular set of their genes (loci). The primary approach employed to address this issue involves conducting a laboratory experiment. During this experiment, a thorough examination was carried out on a set of organic compounds consisting of small DNA elements from the Lactobacillus genus. The Multilocus genotyping method served as the central technique, complemented by additional molecular-biological and population methods. These additional methods were utilized to determine the extent of phylogenetic similarity among pure cultures of Lactobacillus and to classify them accordingly. The article presents the gene isolates that were used for Multilocus typing; the number of L. casei isolates suitable for Multilocus genotyping was revealed; the gene alleles that allowed classifying L. casei isolates into five sequencing types were revealed; the effectiveness of genetic typing method for Multilocus sequencing was substantiated. The article is of practical value for microbiologists and geneticists in the field of molecular biology, as well as for technologists in the food industry. With the development of applied methods in genetic systematics, it has become possible to study pure culture of Lactobacillus species. The application of modern methods of genotypic classification of Lactobacillus species will make it possible to increase the efficiency of using better and safer products in the food industry and medicine.

Meta-analysis data of the accuracy of tests for meat adulteration by real-time PCR.

Adulteration of meat products, including illegal substitution and addition of ingredients, tampering, and the misrepresentation and labelling of food or food ingredients, is becoming a more serious problem globally. The consequences of such manipulations can pose various health risks for consumers, including food allergies and poisoning. This study investigates the problem of meat product adulteration, and detection of the same using real-time polymerase chain reaction (qPCR). Review question: What is the diagnostic accuracy of real-time PCR testing for the detection of meat adulteration? A review via meta-analysis was conducted. Searches were conducted in the Web of Science and MEDLINE (February 2021). All data processing was carried out using Review Manager 5.4 and Meta-Disc 1.4 software.

Characterization of a new bacteriocin-like inhibitory peptide produced by Lactobacillus sakei B-RKM 0559.

The biopreservation strategy allows extending the shelf life and food safety through the use of indigenous or controlled microbiota and their antimicrobial compounds. The aim of this work was to characterize an inhibitory substance with bacteriocin-like activity (Sak-59) produced by the potentially probiotic L. sakei strain from artisanal traditional Kazakh horse meat product Kazy. The maximum production of Sak-59 occurred at the stationary phase of the L. sakei growth. Sak-59 showed inhibitory activity against gram-positive meat spoilage bacteria strains of Listeria monocytogenes, Staphylococcus aureus, and pathogenic gram-negative bacteria strains of Serratia marcescens and Escherichia coli, but not against the tested Lactobacilli strains. Sak-59 activity, as measured by diffusion assay in agar wells, was completely suppressed after treatment with proteolytic enzymes and remained stable after treatment with α-amylase and lipase, indicating that Sak-59 is a peptide and most likely not glycosylated or lipidated. It was concluded that Sak-59 is a potential new bacteriocin with a characteristic activity spectrum, which can be useful in the food and feed industries.