Source Of Lactic Acid Bacteria Research Articles

Isolation and Identification of Probiotic Candidate Lactic Acid Bacteria (Lab) from Shrimp Paste (Mysis relicta) Based on 16s rRNA Gene

Terasi is one of the fermented product of shrimp or fish which is often used as food seasoning by the people. Terasi is also a source of Lactic Acid Bacteria (LAB) which has the potential as a culture for probiotic starters. Probiotics are dietary supplements containing live microbes that profitable to their hosts. This study aimed to identify probiotic lactic acid bacteria isolated from terasi of shrimp based on the 16S ribosomal ribonucleic acid (rRNA) gene sequence. LAB isolation from terasi was done by pour plate method using selective medium, MRSA (Man Rogosa Sharpe Agar). The identification of LAB in this study used a method of molecular with a marker gene of 16S rRNA . A total of 3 isolates were obtained from the isolation process. All LAB isolates are rod (Basil) positive Gram bacteria, negative catalase. Two isolates (TR 1 and TR 2) were identified as Enterococcus faecalis . While one more isolate (TR 3) were identified as Weissella cibaria .

Probiotic Properties of Lactobacillus Species Isolated from Fermented Palm Sap in Thailand.

Lactic acid bacteria (LAB), which are the most frequently used probiotics in foods, confer health benefits such as antimicrobial activity, immune stimulation, and anticancer activity. Fermented palm sap is a potential source of LAB. This study aimed to evaluate in vitro antimicrobial and probiotic properties of LAB isolated from traditional fermented palm sap in Thailand. Among 40 isolated LAB species, 10 were preliminarily selected for their antimicrobial activity. These 10 isolates were identified and confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and 16S rRNA sequencing as Lactobacillus paracasei (8/10), Lactobacillus fermentum (1/10), and Lactobacillus brevis (1/10). They were evaluated for probiotic characteristics and antimicrobial activities against pathogens. These isolates were tolerant toward simulated gastrointestinal tract conditions, including low pH, pepsin, pancreatin, and bile salts. The 10 isolates retained strong auto-aggregation and cell surface hydrophobicity, and they adhered tightly to human intestinal epithelial cells. The isolates were susceptible to ampicillin, erythromycin, clindamycin, tetracycline, and chloramphenicol but resistant to vancomycin, kanamycin, and streptomycin. Moreover, all isolates exhibited no hemolytic activity. All isolates exhibited good antibacterial activity against nine pathogenic bacteria. Thus, these 10 Lactobacillus isolates from fermented palm sap are promising potential candidates for use as probiotics in functional fermented foods and pharmaceutical products.

Probiotics inspired from natural ecosystem to inhibit the growth of Vibrio spp. causing white gut syndrome in Litopenaeus vannamei

The online version contains supplementary material available at 10.1007/s13205-020-02618-2.

Isolation and characterization of Lactococcus garvieae from the fish gut for in vitro fermentation with carbohydrates from agro-industrial waste

This study focused on agro-industrial waste such as fruit peels by extracting prebiotics as a carbon source for lactic acid bacteria (LAB). Four strains of LAB were selected from Oreochromis niloticus (B2 and B3) and Nemipterus japonicas (R4 and R5), and identified as Lactococcus garvieae through 16S rRNA gene sequencing. The analysis of probiotic characteristics revealed that all four strains were able to tolerate sodium chloride (up to 7 %), bile salt (up to 3 %), and broad range of pH (2–9). Further, analysis of polysaccharide contents in the agro-industrial waste materials such as peels of pineapple, orange, lemon, sugarcane, pomegranate, and sweet lemon revealed that the concentration ranged from 3.91–163.85 mg/g. It was observed that orange peels (20.38–140.99 mg/g), sweet lemon peels (22.03–161.93 mg/g), and pomegranate peels (38.19–163.85 mg/g) yielded maximum indigestible polysaccharide. Evaluation of synbiotic combination of probiotic and prebiotic revealed that L. garvieae strains had better fermentation efficiency with orange, sweet lemon, and pineapple compared to lemon, sugarcane, and pomegranate. In nutshell, different types of agro-industrial waste evaluated in this research were found to be a cheap and fermentable carbon sources for LAB. Further study should be conducted to analyze this symbiotic combination as feed supplements for fish in aquaculture as well as various fermentation industries.

EVALUATION OF LACTOBACILLI PROPERTIES AND THEIR ANTIBACTERIAL SUBSTANCES BY USING SWEET WHEY AS GROWTH MEDIUM AGAINST PATHOGENIC BACTERIA

The increasing demand of consumers who look for natural safe products and associated health risks of chemically treated and refined goods food products led to the introduction of alternative technologies for Preservation and maintenance of dietary freshness. One of such Preservation technology requires the use of Lactobacilli as starter culture for the preservation of food matrixes planned. The present study was designed to evaluate sweet whey low-cost by- product of dairy manufacture as a substrate for the selection of Lactobacilli with proven antibacterial activity to be used as biopreservation for fermented dairy product. Human population has used dairy products, including milk, as a source for Lactic acid bacteria (LAB). The positive impact of the given bacteria as a diet supplement has been of concern to researchers. The target of this study is to examine Lactobacillus species isolated from dairy products i.e. raw milk alongside cheese, with potential activities. Using the Sweet whey as growth medium for Lactic acid bacteria. Also, tested of antibacterial activities. Sweet whey (sw) proved to be suitable medium alternative to the expensive commercial De Man-Regosa-Sharp medium for the growth and production of antibacterial substances by isolated lactic acid bacteria isolates. Therefore, was used throughout the present work. A number of 32 isolates were obtained from raw cow milk (16 isolates), goat milk (9 isolates) and cottage cheese (7 isolates) using the specific De Man-RegosaSharp medium (MRS) for the isolation of LAB, these isolates were identified up to genus as strains of Lactobacillus spp. Among 32 isolates of Lactobacillus spp., there are twenty four isolates antagonized of the all seven tested pathogenic bacteria. The screened Lactobacillus spp. isolates were characterized and selected the best bio agent isolate against pathogens was identified using 16s DNA gene to Lactobacillus brevis. This strain was resistant to NaCl (2-6.5 %), produces dioxide carbon (CO2) and showed good growth in different temperature (10°, 15, 45°C) and fermented of many sugars. As per the outcomes shown herein, the strain in question was thought to be antimicrobial bacterium produced a variety of metabolites, including butyric, formic, lactic, citric, and sorbic acid. The given set of activities adds to microbiological safety by helping control microorganism growth, and inhibiting pathogenic bacteria by using the lower-cost sweet whey. Therefore, more detailed work on isolating and characterizing antibacterial bacteria from the locally produces dairy items, and augmenting their growth could be needed for the creation of biopreservative foods.

Evaluation of Lactobacilli properties and their antibacterial substances by using sweet whey as growth medium against pathogenic bacteria

The increasing demand of consumers who look for natural safe products and associated health risks of chemically treated and refined goods food products led to the introduction of alternative technologies for Preservation and maintenance of dietary freshness. One of such Preservation technology requires the use of Lactobacilli as starter culture for the preservation of food matrixes planned.The present study was designed to evaluate sweet whey low-cost by- product of dairy manufacture as a substrate for the selection of Lactobacilli with proven antibacterial activity to be used as biopreservation for fermented dairy product.Human population has used dairy products, including milk, as a source for Lactic acid bacteria (LAB). The positive impact of the given bacteria as a diet supplement has been of concern to researchers. The target of this study is to examine Lactobacillus species isolated from dairy products i.e. raw milk alongside cheese, with potential activities. Using the Sweet whey as growth medium for Lactic acid bacteria. Also, tested of antibacterial activities. Sweet whey (sw) proved to be suitable medium alternative to the expensive commercial De Man-Regosa-Sharp medium for the growth and production of antibacterial substances by isolated lactic acid bacteria isolates. Therefore, was used throughout the present work. A number of 32 isolates were obtained from raw cow milk (16 isolates), goat milk (9 isolates) and cottage cheese (7 isolates) using the specific De Man-Regosa-Sharp medium (MRS) for the isolation of LAB, these isolates were identified up to genus as strains of Lactobacillus spp. Among 32 isolates of Lactobacillus spp. , there are twenty four isolates antagonized of the all seven tested pathogenic bacteria. The screened Lactobacillus spp. isolates were characterized and selected the best bio agent isolate against pathogens was identified using 16s DNA gene to Lactobacillus brevis. This strain was resistant to NaCl (2-6.5 %), produces dioxide carbon (CO2) and showed good growth in different temperature (10°, 15, 45°C) and fermented of many sugars. As per the outcomes shown herein, the strain in question was thought to be antimicrobial bacterium produced a variety of metabolites, including butyric, formic, lactic, citric, and sorbic acid. The given set of activities adds to microbiological safety by helping control microorganism growth, and inhibiting pathogenic bacteria by using the lower-cost sweet whey. Therefore, more detailed work on isolating and characterizing antibacterial bacteria from the locally produces dairy items, and augmenting their growth could be needed for the creation of bio-preservative foods.

Probiotic characteristics of Lactobacillus plantarum E680 and its effect on Hypercholesterolemic mice

BackgroundProbiotics have been reported to reduce total cholesterol levels in vitro, but more evidence is needed to determine the clinical relevance of this activity. Chinese traditional fermented pickles are a good source of lactic acid bacteria. Therefore, pickle samples were collected for screening lactic acid bacteria based on their ability to survive stresses encountered during gastrointestinal passage and cholesterol reducing potency.ResultsSeventy five lactic acid bacteria strains were isolated from 22 fermented pickles. From these bacteria, Lactobacillus plantarum E680, showed the highest acid (85.25%) and bile tolerance (80.79%). It was sensitive to five of the eight antibiotics tested, inhibited the growth of four pathogenic bacteria, and reduced the total cholesterol level by 66.84% in broth culture. In vivo testing using hypercholesterolemic mice fed high-fat emulsion, independent of food intake, found that L. plantarum E680 suppressed body weight gain and reduced total cholesterol and low-density lipoprotein cholesterol levels, with no effect on high-density lipoprotein cholesterol.ConclusionsChinese traditional fermented pickles are a good source for probiotics. L. plantarum E680, isolated from pickles, was acid and bile tolerant, sensitive to antibiotics, and reduced cholesterol levels both in vitro and in vivo. Based on these results, L. plantarum E680 may have potential as a novel probiotic for the development of cholesterol-lowering functional food.

Polyphasic Characterisation of Non-Starter Lactic Acid Bacteria from Algerian Raw Camel’s Milk and Their Technological Aptitudes

SUMMARYResearch backgroundConsumption of spontaneously fermented camel´s milk is common in Algeria, making it a feasible source of diverse lactic acid bacteria (LAB) with the potential to be used as adjunct cultures to improve quality and safety of fermented dairy products.Experimental approachTwelve raw camel´s milk samples were used as a source of indigenous LAB, which were further characterised by examining39 phenotypic traits with technological relevance.Results and conclusionsThirty-five non-starter LAB (NSLAB) were isolated from 12 Algerian raw camel's milk samples and they were microbiologically, biochemically and genetically characterised. Some isolates showed proteolytic activity, acidifying capacity, the ability to use citrate, and to produce dextran and acetoin. Ethanol, acetaldehyde, methyl acetate, acetoin and acetic acid were the major volatile compounds detected. Cluster analysis performed using the unweighted group with arithmetic average (UPGMA) method, and based on the thirty-nine phenotypic characteristics investigated, reflected the microbial diversity that can be found in raw camel´s milk.Novelty and scientific contributionThe isolated strains, from a non-typical source, showed interesting technological traits to be considered as potential adjunct cultures. Cluster analysis based on the examined phenotypic characteristics proved to be a useful tool for the typification of isolates when no genetic information is available. These findings may be of use towards an industrialised production of camel's milk dairy products.

Functional probiotics of lactic acid bacteria from Hu sheep milk

BackgroundProbiotics are being considered as valuable microorganisms related to human health. Hu sheep is referred as one of the important sheep breeds in China. Goat milk produced by Hu sheep is characterized with high nutritional value and hypoallergenic in nature. Particularly, this milk contains plenty of milk prebiotic and probiotic bacteria. This study was aimed to scrutinize more bacterial strains from Hu sheep milk with potential probiotic activity.ResultsBased on 16S rRNA sequence analysis, pool of forty bacterial strains were identified and evaluated their antimicrobial activities against Staphylococcus aureus, enterohemorrhagic Escherichia coli (EHEC), Salmonella typhimurium, Listeria monocytogenes enterotoxigenic E. coli (ETEC) and Aeromonas caviae. Four out of these isolated strains demonstrated their efficient bacteriostatic ability and potential healthy properties. We also examined the safety aspects of these bacterial candidates including three Lactococcus lactis strains (named as HSM-1, HSM-10, and HSM-18) and one Leuconostoc lactis strain (HSM-14), and were further evaluated via in vitro tests, including antimicrobial activity, cell surface characteristics (hydrophobicity, co-aggregation, and self-aggregation), heat treatment, antibiotic susceptibility, simulated transport tolerance in the gastrointestinal tract, and acid/bile tolerance. The obtained results revealed that HSM-1, HSM-10, HSM-14, and HSM-18 showed high survival rate at different conditions for example low pH, presence of bovine bile and demonstrated high hydrophobicity. Moreover, HSM-14 had an advantage over other strains in terms of gastrointestinal tract tolerance, antimicrobial activities against pathogens, and these results were significantly better than other bacterial candidates.ConclusionHu sheep milk as a source of exploration of potential lactic acid bacteria (LAB) probiotics open the new horizon of probiotics usage from unconventional milk sources. The selected LAB strains are excellent probiotic candidates which can be used for animal husbandry in the future. Rationale of the study was to utilize Hu sheep milk as a source of potential probiotic LABs. The study has contributed to the establishment of a complete bacterial resource pool by exploring the Hu sheep milk microflora.

New enterococci isolated from cheese whey derived from different animal sources: High biotechnological potential as starter cultures

Whey is one of the most important byproducts of dairy industries. The potential of lactic acid bacteria from cheese whey as starter cultures is unexplored. Thus, this study aims to isolate cheese whey lactic-acid bacteria (LAB) from cow, goat, and buffalo milk, and characterize their potential of providing different tastes and flavors for fermented beverages. We selected the most promising LAB for preparation of new fermented milks. Bacterial isolation resulted in 94 Gram-positive, catalase-negative, and acid-producer LAB isolates: 40 from cow, 37 from buffalo, and 17 from goat cheese whey. Non-metric MDS analysis showed that the pattern of technological characteristics of LAB from cow and buffalo cheese whey was similar. Based on these characteristics, we chose five LAB for preparation of fermented milks, as follows: BC1 (control) milk fermented with the commercial LAB (SLB95); BC2 (new LAB isolates) with Enterococcus sp. CW36, BW32, and GW33; and BC3 (new LAB isolates) with Enterococcus sp. CW36, GW34 and Lactococcus sp. BW27.74 untrained panelists participated in a sensory test. According to them, appearance, aroma, and flavor of the new fermented milk BC3 were better (p < 0.05). The results show that cheese whey can be a source of new LAB that can be used in dairy industry with a great potential as starter cultures.

Large-scale genome-wide analysis links lactic acid bacteria from food with the gut microbiome

Lactic acid bacteria (LAB) are fundamental in the production of fermented foods and several strains are regarded as probiotics. Large quantities of live LAB are consumed within fermented foods, but it is not yet known to what extent the LAB we ingest become members of the gut microbiome. By analysis of 9445 metagenomes from human samples, we demonstrate that the prevalence and abundance of LAB species in stool samples is generally low and linked to age, lifestyle, and geography, with Streptococcus thermophilus and Lactococcus lactis being most prevalent. Moreover, we identify genome-based differences between food and gut microbes by considering 666 metagenome-assembled genomes (MAGs) newly reconstructed from fermented food microbiomes along with 154,723 human MAGs and 193,078 reference genomes. Our large-scale genome-wide analysis demonstrates that closely related LAB strains occur in both food and gut environments and provides unprecedented evidence that fermented foods can be indeed regarded as a possible source of LAB for the gut microbiome.

Prevalence and abundance of lactic acid bacteria in raw milk associated with forage types in dairy cow feeding

Lactic acid bacteria (LAB) found in milk can be responsible for organoleptic defects in cheese. To identify sources of LAB that could potentially develop during cheese making, we evaluated their prevalence and abundance in milk according to the type of forage used in dairy cow feeding. Forages and bulk tank milk were sampled 3 times on 24 farms using either hay alone (control), or grass or legume silage supplemented with corn silage or not. Both types of silage were either non-inoculated or inoculated with commercial preparations containing at least a Lactobacillus buchneri strain along with Lactobacillus casei, Lactobacillus plantarum, Enterococcus faecium, or Pediococcus pentosaceus. Our results indicate that LAB viable counts in milk samples (2.56 log cfu/mL) did not differ according to the type of forage used. A total of 1,239 LAB were isolated and identified by partial 16S rRNA gene sequencing. Although inoculation increased lactobacilli abundance in grass silage by 35%, we did not observe an effect on the LAB profile of milk. Indeed, we found no significant difference in milk LAB prevalence and abundance according to the type of forage (P > 0.05). Moreover, isolates belonging to the L. buchneri group were rarely found in bulk tank milk (3 out of 481 isolates). Random amplified polymorphic DNA typing of 406 LAB isolates revealed the plausible transfer of some strains from silage to milk (~6%). Thus, forage is only a minor contributor to LAB contamination of milk.

Molecular characterization of lactic acid bacteria producing edible biofilm isolated from kimchi

Biofilm is a community of microorganisms that interrelated and covered by an extracellular polymer matrix. This biofilm can be produced by Lactic acid bacteria (LAB) which was edible for human and animal. Therefore, it possible to be applied in the food and health industry. One source of LAB is kimchi, as fermented food from Korea and it has good benefits for health. This research aimed to obtain LAB from kimchi that can produce edible biofilms and to identify LAB producing edible biofilms based on the 16S rRNA gene. Isolation of lactic acid bacteria from kimchi cultured in MRS agar medium containing 1% CaCO3, biofilm production test with biofilm assay method and zeolite as a substrate to adherent cells. For amplification of 16S rRNA gene used primer 27F and 1492R. The isolate of KA2, KA5, KB1, and KC4 isolated from kimchi and could produce biofilms with the highest biofilm formation at 48 hours incubation time. Based on molecular identification with 16S rRNA gene sequencing, the four isolates identified as Lactobacillus brevis species.

Select a protective agent for encapsulation of Lactobacillus plantarum

Five carbohydrates were applied as protective agents for encapsulation of Lactobacillus plantarum FT 35 which produced high acid and had ability to inhibit some pathogenic bacteria. They had glass transition temperatures in ascending order from glucose, sucrose, lactose, maltodextrin to soluble starch. The soluble starch demonstrated the best protection to cell during drying process and storage. The accretion of soluble starch higher than 2.5% in feed-in mixture for spray drying exhibited the increase in the viscosity of mixtures and the particle size of products. These products contained less number of viable cells and higher cell injury. The encapsulated products with 2.5% soluble starch exhibited a better storage stability than those with 1.5%. The encapsulated product was applied as a co-starter in pla-som fermentation without additional of carbon sources and also demonstrated fast acid production. The fermentation with encapsulated products displayed better inhibitory effect on inoculated pathogenic bacteria than indigenous fermentation. The soluble starch serves as a protective agent for encapsulated culture and also a good carbon source for lactic acid bacteria in the fermentation of pla-som.

In Vitro Characterization of Lactic Acid Bacteria from Indonesian Kefir Grains as Probiotics with Cholesterol-Lowering Effect.

Indonesian kefir grains are potential sources of lactic acid bacteria (LAB) that may act as probiotics with specific functional properties. In this study we explored the potential of the probiotic and cholesterol-lowering effect of LAB isolated from Indonesian kefir grains obtained from Bogor, Bandung, Jakarta, and Yogyakarta. The results revealed that 10 isolates showed considerable survivability at low pH and bile salt with total cell reduction of ~3 log colony-forming units per milliliter after exposure to pH 2.5 and 0.5% (w/v) bile salt for 1 and 3 h, respectively. All strains exhibited strong antimicrobial activities against pathogenic bacteria and were sensitive to a wide spectrum of antibiotics but exhibited weak bile salt hydrolase activity. Identification based on 16S RNA suggested that nine isolates were Lactobacillus kefiri and one was Lactobacillus rhamnosus. The ability of the isolates to reduce cholesterol from the media varied, ranging from 22.08% to 68.75% with the highest reduction shown by L. kefiri JK17. The ability to remove cholesterol from the media decreased greatly in resting and dead cells, ranging from 14.58% to 22.08% in resting cells and from 7.89% to 18.17% in dead cells. It can be concluded that Indonesian kefir grains contain LAB potentially acting as probiotics capable of reducing cholesterol. The cholesterol-lowering effect especially occurs when the cells are metabolically active.

Ex Vivo Study of Laban's Role in Decreasing Hemolysis Crisis in G6PD-Deficient Patients.

In spite of the vast nutritional and environmental benefits provided by fava bean (Vicia faba), the ingestion of vicine/convicine provokes an acute hemolytic anemia called favism in individuals with a glucose-6-phosphate dehydrogenase (G6PD) deficiency. The elimination of these glycosides is a goal that could be accomplished using different processing methods including bacteriological treatment. Laban as a good source of lactic acid bacteria was tested in an ex vivo assay on human blood samples in order to determine its capacity in decreasing the hemolysis crisis induced by the ingestion of fava beans. Results indicate a significant decrease in human blood cell hemolysis after the treatment of fava beans by Laban. This decrease in hemolysis was also correlated with the G6PD deficiency categorization. The highest hemolysis level (mean: 23.11 ± 0.76%) was observed in samples with G6PD activity between 10 and 30%, while the lowest hemolysis level (mean: 5.75 ± 0.64%) was observed in samples with G6PD activity more than 60%. This decrease was correlated with a high antioxidant capacity of Laban (51.61 ± 1.13% expressed by the percentage inhibition of DPPH radical). The counts of isolates from MRS and M17 culture plates were 6.75 ± 0.095 and 7.91 ± 0.061 log cfu ml–1, respectively. In conclusion, the synergy between the antioxidant properties of Laban and the possible decrease of vicine and convicine concentrations by lactobacillus found in the fermented dairy products could explain the ability of Laban to reduce the hemolysis crisis ex vivo.

Lactic Acid Bacteria Isolation from Spontaneous Sourdough and Their Characterization Including Antimicrobial and Antifungal Properties Evaluation.

This research effort aimed at isolating and phenotypically characterizing lactic acid bacteria (LAB) isolates from a spontaneous rye sourdough manufactured following traditional protocols, as well as at evaluating their antimicrobial and antifungal properties as key features for future industrial applications. Thirteen LAB strains of potential industrial interest were isolated and identified to species-level via PCR. Most of the sourdough isolates showed versatile carbohydrate metabolisms. The Leuconostoc mesenteroides No. 242 and Lactobacillus brevis No. 173 demonstrated to be gas producers; thus, revealing their heterofermenter or facultative homofermenter features. Viable counts higher than 7.0 log10 (CFU/mL) were observed for Lactobacillus paracasei No. 244, Lactobacillus casei No. 210, L. brevis No. 173, Lactobacillus farraginis No. 206, Pediococcus pentosaceus No. 183, Lactobacillus uvarum No. 245 and Lactobacillus plantarum No. 135 strains, after exposure at pH 2.5 for 2 h. Moreover, L. plantarum No. 122, L. casei No. 210, Lactobacillus curvatus No. 51, L. paracasei No. 244, and L. coryniformins No. 71 showed growth inhibition properties against all the tested fifteen pathogenic strains. Finally, all LAB isolates showed antifungal activities against Aspergillus nidulans, Penicillium funiculosum, and Fusarium poae. These results unveiled the exceptionality of spontaneous sourdough as a source of LAB with effective potential to be considered in the design of novel commercial microbial single/mixed starter cultures, intended for application in a wide range of agri-food industries, where the antimicrobial and antifungal properties are often sought and necessary. In addition, metabolites therefrom may also be considered as important functional and bioactive compounds with high potential to be employed in food and feed, as well as cosmetic and pharmaceutical applications.

Viability of lactic acid bacteria in different components of Ogi with anti diarrhoeagenic E. coli activities

Background: Ogi constitutes a rich source of lactic acid bacteria (LAB) with associated health benefits to humans through antimicrobial activities. However, the high viability of LAB in Ogi and its supernatant (Omidun) is essential. Aims: This study was carried out to assess the viability of LAB in various forms of modified and natural Ogi and the antimicrobial properties of Omidun against diarrhoeagenic E coli. Methods and Material: The viability of LAB was assessed in fermented Ogi slurry and Omidun for one month and also freeze-dried Ogi with and without added bacterial strains for two months. A further 10 days viability study of modified Omidun, refrigerated Omidun, and normal Ogi was performed. The antimicrobial effects of modified Omidun against five selected strains of diarrhoeagenic E. coli (DEC) were evaluated by the co-culture method. Results: Both drying methods significantly affected carotenoids and phenolic compounds. The Ogi slurry had viable LAB only for 10 days after which, there was a succession of fungi and yeast. Omidun showed 2 log10cfu/ml reduction of LAB count each week and the freeze-dried Ogi showed progressive reduction in viability. Refrigerated Omidun has little viable LAB, while higher viability was seen in modified Omidun (≥2 log cfu/ml) than normal Omidun. Modified Omidun intervention led to 2-4 log reduction in diarrhoeagenic E. coli strains and total inactivation of shigella-toxin producing E. coli H66D strain in co-culture. Conclusions: The consumption of Ogi should be within 10 days of milling using modified Omidun. There are practical potentials of consumption of Omidun in destroying E. coli strains implicated in diarrhea. Keywords: Ogi, Omidun, lactic acid bacteria, diarrhoeagenic Escherichia coli strains, Viability.

Genomic Insights Into Five Strains of Lactobacillus plantarum With Biotechnological Potential Isolated From chicha, a Traditional Maize-Based Fermented Beverage From Northwestern Argentina.

Lactic acid bacteria (LAB) are indigenous microorganisms that have been involved in food fermentations throughout history to preserve food and also to give special characteristics to them. The traditional fermented foods that are still being elaborated in indigenous populations around the world are a potential source of LAB with important biotechnological properties and/or beneficial to health. In a previous work, LAB biodiversity associated with chicha, a traditional maize-based fermented beverage from Northwestern Argentina, was studied, both by culture dependent and independent methods. From that study, 392 isolates were recovered, mostly members of Lactobacillus and Leuconostoc. Biotechnological characterization of representative isolates led to the selection of five strains belonging to the species Lactobacillus plantarum for their ability to produce vitamin B2 (riboflavin) and vitamin B9 (folates), their antimicrobial properties and antibiotics susceptibility. In this work, we present the Whole Genome Sequences (WGS) of these five strains that have been deposited in the Spanish Type Culture Collection: M5MA1 (= CECT 8962), M9MM1 (= CECT 8963), M9MM4 (= CECT 8964), M9MG6 (= CECT 8965), and M9Y2 (= CECT 8966), and a detailed description of their characterization, through a genomic approach, analyzing the genes responsible for these biotechnological properties, making a comparative study of the five genomes and reporting the aspects related to food safety, in accordance with the recommendations of the European Food Safety Authority (EFSA FEEDAP Panel, 2018) aiming at their use in the design of functional foods. The analysis unveiled, for the five strains, the complete set of genes for folate and riboflavin biosynthesis, the absence of pathogenic factors, the presence of CRISPR and cas genes, phage sequences, insertion elements and an aminoglycosides resistance gene, aadA, whose resistance could not be proved phenotypically in any strain. Genomic comparisons showed that strain CECT 8962 was significantly different in terms of genetic content and allowed the identification of carbohydrates metabolism and membrane transport related genes as the main components of the unique and accessory genome.

AKTIVITAS ANTIMIKROBA BAKTERI ASAM LAKTAT YANG DIISOLASI DARI MAKANAN TRADISIONAL FERMENTASI KHAS BATAK “NANIURA”

Lactic acid bacteria (LAB) could be isolated from various fermented food products. One potential source of LAB is traditional fermented food. The aim of the study was to isolate and investigate antimicrobial activity of LAB isolated from traditional Batak food, “naniura”. The LAB isolates were characterized by Gram staining, fermentation type and catalase test. The investigation of antimicrobial activity of LAB against pathogenic bacteria were conducted using disc diffusion method. The results showed that 6 isolates of BAL were successfully isolated namely BN1, BN2, BN3, BN4, BN5 and BN6 had characteristics of Gram positive, rod shaped and catalase negative. All selected isolate have heterofermentation type. Four isolates (BN1, BN2, BN5 and BN6) were able to inhibit S. aureus, E. coli and S. typhi with inhibition zone diameters ranging from 6,9 to 12,3 cm. Based on the result, it was concluded that LAB isolated from naniura has potential as a source of probiotics.