scholarly journals Tracking of Intentionally Inoculated Lactic Acid Bacteria Strains in Yogurt and Probiotic Powder

2019 ◽  
Vol 8 (1) ◽  
pp. 5 ◽  
Author(s):  
Anshul Sharma ◽  
Jasmine Kaur ◽  
Sulhee Lee ◽  
Young-Seo Park
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Gene Sequence ◽  
Random Amplified Polymorphic Dna ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
Sequence Alignments ◽  
Gene Sequence Analysis ◽  
Rrna Gene Sequencing

The present work aimed at tracking intentionally inoculated lactic acid bacteria (LAB) strains in yogurt and probiotic powder. Leuconostoc (Leu.) mesenteroides (11251), Lactobacillus (L.) brevis (B151), and Lactobacillus plantarum (LB41K) strains were tracked in yogurt, and L. plantarum (LB41P) was tracked in a commercial probiotic powder. The yogurt was intentionally inoculated with the selected bacterial strains. Two types of yogurt with known and unknown bacterial pools were utilized. The standard 16S rRNA gene sequencing was used to evaluate the initial screening. The molecular typing tools, random amplified polymorphic DNA (RAPD), repetitive element palindromic PCR (rep-PCR), and comparative gene sequence analysis of selected housekeeping loci were used to track the inoculated dubious strains. Out of 30 random selections for each inoculation, the developed method identified seven (11251), nine (B151), and five (LB41K) colonies in the yogurt. The validation was performed by identifying 7 colonies (LB41P) out of 30 in the probiotic powder. The DNA banding profiles and the gene sequence alignments led to the identification of the correct inoculated strains. Overall, the study summarizes the use of molecular tools to identify the deliberately inoculated LAB strains. In conclusion, the proposed polyphasic approach effectively tracked the intentionally inoculated strains: Leu. mesenteroides, L. brevis, and L. plantarum (LB41K) in yogurt and L. plantarum (LB41P) in probiotic powder. The study demonstrates how to track industrially relevant misused LAB strains in marketable food products.

Characterization of bacteria and antibiotic resistance in commercially-produced cheeses sold in China

2021 ◽  
Author(s):  
Jinghui Yao ◽  
Jing Gao ◽  
Jianming Guo ◽  
Hengan Wang ◽  
En Zhang ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Acquired Resistance ◽  
Antibiotic Resistance Genes ◽  
16S Rrna Gene Sequencing ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Rrna Gene ◽  
Rrna Gene Sequencing

The consumption of cheese in China is increasing rapidly. Little is known about the microbiota, the presence of antibiotic-resistant bacteria, or the distribution of antibiotic resistance genes (ARGs) in commercially-produced cheeses sold in China. These are important criteria for evaluating quality and safety. Thus, this study assessed the metagenomics of fifteen types of cheese using 16S rRNA gene sequencing. Fourteen bacterial genera were detected. Lactococcus , Lactobacillus , and Streptococcus were dominant based on numbers of sequence reads. Multidrug-resistant lactic acid bacteria were isolated from most of the types of cheese. The isolates showed 100% and 91.7% resistance to streptomycin and sulfamethoxazole, respectively, and genes involved in acquired resistance to streptomycin ( strB) and sulfonamides ( sul2) were detected with high frequency. To analyze the distribution of ARGs in the cheeses in overall, 309 ARGs from eight categories of ARG and nine transposase genes were profiled. A total of 169 ARGs were detected in the 15 cheeses; their occurrence and abundance varied significantly between cheeses. Our study demonstrates that there is various diversity of the bacteria and ARGs in cheeses sold in China. The risks associated with multidrug resistance of dominant lactic acid bacteria are of great concern.

scholarly journals Prevotella dentasini sp. nov., a black-pigmented species isolated from the oral cavity of donkeys

2010 ◽  
Vol 60 (7) ◽  
pp. 1637-1639 ◽  
Author(s):  
Kazuko Takada ◽  
Kazuhiko Hayashi ◽  
Yutaka Sato ◽  
Masatomo Hirasawa
Keyword(s):  
16S Rrna ◽  
Oral Cavity ◽  
16S Rrna Gene ◽  
Dna Hybridization ◽  
Gene Sequence ◽  
Sequence Similarity ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Gene Sequence Analysis ◽  
Rrna Gene Sequencing

Four strains (NUM 1903T, NUM 1904, NUM 1912 and NUM 1925) that were obligately anaerobic, pigmented, Gram-negative-staining rods were isolated from the oral cavity of donkeys. These strains were analysed using the Rapid ID 32A, API 20A and API ZYM systems, by DNA–DNA hybridization with other related species and by 16S rRNA gene sequencing. 16S rRNA gene sequence analysis showed that each of the new isolates was a member of the genus Prevotella and related to Prevotella multiformis PPPA21T, showing about 93 % sequence similarity. Based on phylogenetic and phenotypic evidence, it is proposed that the four strains are representatives of a novel species, for which the name Prevotella dentasini sp. nov. is proposed. The type strain is NUM 1903T (=JCM 15908T=DSM 22229T).

scholarly journals Distribution and antimicrobial activity of lactic acid bacteria associated with lychee fruits

2020 ◽  
Vol 25 (6) ◽  
pp. 2079-2085
Author(s):  
LIN-HU NAN ◽  
◽  
YI-SHENG CHEN ◽  
HUI-CHUNG WU ◽  
YU-CHING SU ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
16S Rrna ◽  
Novel Species ◽  
16S Rrna Gene Sequencing ◽  
Mass Spectrometry Analysis ◽  
Rrna Gene ◽  
Spectrometry Analysis ◽  
Gram Positive Bacteria ◽  
Rrna Gene Sequencing

Lychee is a popular fruit in China and southeastern Asia. Although it is very popular, the microbiota of lactic acid bacteria (LAB) associated with lychee remains poorly described. Lychee samples from seven different markets located in three cities in Taiwan were collected and a total of 104 LAB were isolated. Through RFLP analyses of 16S rDNA and rpoA genes for grouping and 16S rRNA gene sequencing, these isolates were finally divided into 6 groups (A to F). The most common genera of LAB in lychee samples were Weissella and Leuconostoc. Weissella confusa strain E was found to produce a bacteriocin active against Listeria monocytogenes and some other Gram-positive bacteria. Mass spectrometry analysis revealed the bacteriocin mass to be approximately 3426.77 Da, which is different to other known Weissella bacteriocins. In addition, strain MB7 included in the genus Leuconostoc was identified as potential novel species or subspecies on the basis of phylogenetic analysis of 16S rRNA, rpoA and pheS gene sequences. Thus, this is the first report describing the distribution and varieties of LAB associated with lychee fruits. In addition, one potential novel LAB species or subspecies and one potential novel bacteriocin were also reported in this study.

scholarly journals Starter cultures of lactic acid bacteria for special diet products

2017 ◽  
Vol 1 (1) ◽  
pp. 89-90 ◽  
Author(s):  
Hanna Aljaksandrauna Bareika ◽  
Anatasija Vyachaslavauna Sidarenka ◽  
Galina Ivanovna Novik
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Gene Sequencing ◽  
16S Rrna Gene Sequencing ◽  
Starter Cultures ◽  
Protein Profiling ◽  
Rrna Gene ◽  
Biochemical Characteristics ◽  
Special Diet ◽  
Rrna Gene Sequencing

Abstract From fresh and fermented vegetables (cucumber, sauercraut, eggplant), cereals (wheat, rice), legumes (soy) 37 cultures of lactic acid bacteria were isolated. Based on biochemical characteristics, MALDI-TOF MS protein profiling and 16S rRNA gene sequencing they were identified as representatives of Lactobacillus, Lactococcus, Leuconostoc, Pediococcus and Enterococcus genera. Six members of Lactobacillus genera and two members of Leuconostoc genera actively producing EPS were selected for further investigation as components of starters for production of special dietetic foodstuffs.

scholarly journals Molecular Identification of Yeasts and Lactic Acid Bacteria Involved in the Production of Beninese Fermented Food Degue

2017 ◽  
Vol 11 (1) ◽  
pp. 94-104 ◽  
Author(s):  
Angel I. Angelov ◽  
Galya Petrova ◽  
Angel D. Angelov ◽  
Petya Stefanova ◽  
Innocent Y. Bokossa ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Sequence Analysis ◽  
Lactic Acid Bacteria ◽  
Gene Sequence ◽  
Microbial Population ◽  
Fermented Food ◽  
Starter Cultures ◽  
Rrna Gene ◽  
Rrna Gene Sequence ◽  
Gene Sequence Analysis

Background:Traditional Beninese fermented food Degue is widely consumed in Benin and other countries in West Africa. It was originally made from milk and millet flour, but currently other cereals are used as well. Nowadays, Degue production occurs by spontaneous fermentation in individual households and information about the microorganisms involved is currently limited.Objective:The microbiota of Degue from Benin has not been studied so far, but its growing production in the country sets a demand for revealing the biodiversity of the microbial population involved in the fermentation process in order to take future steps for development of industrial technology and offer products with improved quality and safety.Method:In the present study, yeast and lactic acid bacteria from raw materials for Degue production and from several Degue products were isolated and identified by molecular methods including RFLP and ITS1-5.8S-ITS2 rRNA gene sequence analysis in yeasts, and 16S rRNA gene sequence analysis in lactic acid bacteria.Results:Lactic acid bacteria isolates were assigned to eight species within the generaLactobacillus,Enterococcus,Pediococcus,StreptococcusandWeisella. Four species of yeasts were found in Degue:Cyberlyndnera fabianii,Candida glabrata,Kluyveromyces marxianus, andMeyerozyma caribbica.Conclusion:The microbial population revealed is unique to Beninese Degue and needs further characterization for development of defined starter cultures.

scholarly journals Weissella beninensis sp. nov., a motile lactic acid bacterium from submerged cassava fermentations, and emended description of the genus Weissella

2010 ◽  
Vol 60 (9) ◽  
pp. 2193-2198 ◽  
Author(s):  
Sègla Wilfrid Padonou ◽  
Ulrich Schillinger ◽  
Dennis S. Nielsen ◽  
Charles M. A. P. Franz ◽  
Michael Hansen ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Gene Sequence ◽  
Novel Species ◽  
Rrna Gene ◽  
Rrna Gene Sequence ◽  
Bacterial Strains ◽  
Gas Formation ◽  
Dna Reassociation ◽  
Gene Sequence Analysis ◽  
Emended Description

Four Gram-positive, catalase-negative, short rod-shaped or coccoid, heterofermentative lactic acid bacterial strains (2L24P13T, 1L48P15, 1L24P31 and 1L24P34) with unusual phenotypic and genotypic properties were isolated from submerged fermenting cassava on MRS agar. All strains were motile, grew at 15 °C, produced dl-lactic acid from glucose with gas formation and produced ammonia from arginine. Acid was produced from d-fructose, d-galactose, d-glucose, lactose, maltose, d-mannose, melibiose, d-raffinose, sucrose, N-acetylglucosamine and d-mannitol, but not from d-arabinose or xylose. 16S rRNA gene sequence analysis revealed that the strains belonged to the genus Weissella and were most closely related to Weissella ghanensis LMG 24286T . Low DNA−DNA reassociation values were obtained between the isolates and W. ghanensis DSM 19935T. Based on the genetic and phenotypic results, the strains are considered to represent a novel species, for which the name Weissella beninensis sp. nov. is proposed. The type strain is 2L24P13T (=DSM 22752T=LMG 25373T).

scholarly journals Rep PCR Characterization of Lactic Acid Bacteria Isolated From Raw Cows’ Milk in Algeria.

2021 ◽  
Author(s):  
Akil LOMANI ◽  
Dennis S Nielsen ◽  
Larbi Ahmed Amine ◽  
Tahri Ahmed ◽  
Mediani Ahmed
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Bile Salts ◽  
Acid Tolerance ◽  
16S Rrna Gene Sequencing ◽  
Fermented Milk ◽  
Haemolytic Activity ◽  
Rrna Gene ◽  
Rrna Gene Sequencing

Abstract Milk and indigenous fermented, milk based products are a rich source of lactic acid bacteria (LAB) and may serve as a source of potential probiotics. In the present study LAB were isolated from raw cows’ milk sampled at five different Algerian farms. A total of 24 Gram positive, catalase negative isolates where identified to species level using a combination of (GTG) 5-based rep-PCR fingerprinting and 16S rRNA gene sequencing. All isolates were identified as Enterococcus faecium and all isolates had highly similar rep-PCR profiles. Four representative isolates were screened for acid tolerance, bile salts tolerance, antimicrobial susceptibility, antibacterial activity and haemolysis. The four selected strains all exhibited good tolerance to low pH (2, 3, and 4), and to bile salts (concentrations of 0.5%, 1%, and 2%) and were sensitive to chloramphenicol, vancomycin, tetracycline, gentamicine and peniciline G, but were resistant to oxaciline. Cell-free supernatants of the four tested strains all inhibited Staphylococcus aureus, Escherichia coli and Listeria monocytogenes but not Salmonella Typhi. No haemolytic activity was observed.

scholarly journals Isolation and identification of bacteriocin-producing lactic acid bacteria from plants in Mount Makiling Forest Reserve, Philippines

2019 ◽  
pp. 1-15
Author(s):  
Emil Lat ◽  
Francisco Elegado ◽  
Ida Dalmacio
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Bootstrap Method ◽  
16S Rrna Gene Sequencing ◽  
Indicator Strain ◽  
Homology Search ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
Isolation And Identification ◽  
Forest Reserve

Sixty-three lactic acid bacteria (LAB) were isolated from trapped or stagnated water in parts of 14 different plant species in Mount Makiling Forest Reserve, Philippines and were screened for bacteriocin production. Thirteen of these isolates were found antagonistic to different indicator bacterial strains through direct assay. However, after screening of the pH neutralized culture supernatant using ‘spot-on-lawn’ method against Enterococcus faecium 79 as the indicator strain, only one isolate, designated as ML 258, was confirmed to be bacteriocin-producer. Its crude extract of bacteriocin exhibited inhibitory activity against E. faecium and Lactobacillus aciclophilus. The isolate was characterized and found to be gram-positive short rods that occurred in pairs, singly or in chains, catalase negative, microaerophilic, non-motile, non-spore forming and exhibited a heterofermentative type of fermentation. This isolate was obtained from fern (Microsorum longissimus) and was identified as Carnobacterium piscicola using API 50 CHL kit with good identification of 98%. However, the 16S rRNA gene sequencing and homology search from NCBI database using the BLAST program showed that the isolate is 93-95% similar with Carnobacterium maltaromaticum. On the other hand, phylogenetic analysis using MEGA 5 software that constructed a neighbor joining tree thru bootstrap method revealed that this isolate showed more similarity with Enterococcus sp.

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