Lactobacillus Isolates Research Articles

Ameliorated Viability of Lactic Acid Bacteria in Fruit Juice Isolated from Indigenous Dahi with Prebiotics (Asparagus falcatus and Zingiber officinale)

Dahi is a fermented milk product containing probiotic lactic acid bacteria. This study aimed to isolate, identify, and characterize lactic acid-producing bacteria from native Dahi and evaluate their viability in orange juice using natural prebiotics. Dahi samples were obtained from local shops in Chattogram and Bogura, Bangladesh. Lactic acid-producing bacteria were isolated using MRS (de Mann Rogosa and Sharpe) medium. The isolated bacteria were identified through colony morphology, biochemical tests, and probiotic characteristics. Molecular identification was performed using polymerase chain reaction (PCR) targeting conserved 16S rDNA regions. Isolates of the genus Lactobacillus and Lactococcus lactis sp. Lactis were confirmed and used to develop probiotic orange juice. Prebiotics (Asparagus falcatus and Zingiber officinale) were added to the juice to support probiotic growth. The inoculated cell’s viability and the juice’s physicochemical parameters were evaluated during fermentation (48 hours) and storage (28 days). All fruit juice samples showed a mean number of viable cells of at least 1×105 CFU/mL during the 48-hour fermentation and 28-day storage in the refrigerator. Using natural prebiotics positively affected the survival of lactic acid bacteria, as demonstrated by bacterial colony growth on Petri dishes. Developing probiotic fruit juice enriched with prebiotics could be an effective alternative for individuals allergic or intolerant to milk-based products. Incorporating lactic acid bacteria from native Dahi into orange juice, combined with natural prebiotics, resulted in viable probiotic cells throughout fermentation and storage.

Isolation of Lactobacillus spp. from Healthy Infants' Feces and Study of their Antibiotic Susceptibility

This study aimed to isolate Lactobacillus spp. bacteria from the feces of healthy newborns and investigate their susceptibility to antibiotic resistance. 120 fecal samples were obtained from infants under 12 months of age and susceptibility was identified using biochemical tests and molecular identification methods. A total of 30 positive isolates, chosen randomly from the 90 positive samples, were selected to conduct a safety assessment. the isolates were analyzed for their hemolytic activity and susceptibility to antibiotics. Using 16S rRNA sequencing, a total of 30 positive isolates were determined to be lactobacillus spp. The results of the antibiotic resistance test indicated that the majority of the isolates showed susceptibility to tetracycline, chloramphenicol, gentamicin, clindamycin, and amoxicillin while demonstrating resistance to vancomycin, nalidixic acid, streptomycin, and amikacin. conclusion: Based on these specific traits, the isolates of Lactobacillus spp. demonstrated favorable qualities as probiotics.

Characterization of indigenous lactobacilli from dairy fermented foods of Haryana as potential probiotics utilizing multiple attribute decision-making approach

The interest in region-specific ethnic fermented foods and their functional microbiota is rising. The demands for functional foods are continuously rising, so research is going on to develop nutritious food with many beneficial attributes and low safety concerns. The present study was designed to isolate and characterize lactobacilli probiotic candidates from locally resourced fermented foods (dahi, lassi, and raabadi) to make ready-to-eat fermented functional products later. Cultures were isolated from 82 fermented food samples collected from different villages. The initial experiments of gram staining, catalase test, and carbohydrate fermentation were assessed for the morphology, purity, and primary characterization on the genus level, which was verified through molecular characterization using PCR. Seven lactobacilli strains (no. MS001-MS007) were then assessed for safety, probiotic candidacy, phytase degradation, and biofilm forming abilities. All seven bacterial cultures showed no hemolytic activity and antibiotic sensitivity against more than 14 antibiotics out of 20. All seven lactobacilli isolates were able to tolerate pH 3.0, 0.3% bile 0.5% pancreatin, lysozyme (100 mg/L to 300 mg/L) and also shown possessed phytase degradation ability. All the cultures showed antioxidative potential and biofilm formation ability. Culture MS007 showed considerably higher bile salt hydrolase activity among all the isolates, whereas MS005 possessed excellent phytate degradation ability among others. Bacterial strains were identified using 16S rRNA gene sequencing. Moreover, the order of preference of isolates was calculated using the multidimensional Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) based on probiotic and other functional properties. The most promising attributes showing cultures were recognised as Limosilactobacillus fermentum MS005 and Lactiplantibacillus plantarum MS007, which could be further used for functional food product development.Graphical

Ensuring Tree Protection, Growth and Sustainability by Microbial Isolates

Antimicrobial properties of the new strains of micro-organisms isolated from natural sources of various ecological niches in the Moscow region and the Republic of Tatarstan were studied. Antifungal activity of isolates was detected in a test culture of toxin-producing microscopic fungi that can cause animal and plant diseases: Aspergillus flavus, Candida albicans, Fusarium oxysporum and Penicillium spp. Of the 46 studied micro-organisms of genera Bacillus, Lactobacillus, Lactococcus and Streptomyces isolates, there are four strains (Bacillus subtilis, Lactobacillus plantarum, Propionibacterium freudenreichii and Streptomyces spp.) that showed an ability to produce biologically active metabolites with a pronounced antimicrobial potential against phytopathogenic fungi metabolites. Based on the selected four strains, a Bacterial product LRV composition has been created. Scots pine, pedunculate oak and small-leaved linden seedlings with single and double foliar treatment and Bacterial product LRV at a concentration of 10 mL/L led to an increase in the growth of the aboveground part by 31.8, 51.9 and 25.4%, respectively, and the underground part by 25.0, 37.2 and 25.7%, respectively, compared to the control. The weight of seedlings at the end of the study exceeded the control variant by an average of 26.0, 44.0 and 78.0%, respectively. Plant protection Bacterial product LRV use did not have a significant effect on the group of molds that caused the powdery mildew and Schütte disease damage to trees. The Biological product LRV provided plant protection from fungal diseases caused by Lophodermium pinastri Chev. and Microsphaera alphitoides.

In vitro characterization of probiotic potential of Lactobacillus plantarum CM49 against selected cattle mastitogens

BackgroundBovine mastitis results in significant economic losses for the dairy industry globally due to milk production losses and decreased herd efficiency. This research aimed to isolate, select, and characterize indigenous lactobacilli with probiotic properties. A total of 40 lactobacilli were isolated from healthy milk samples of cattle and identified at the species level through 16S rDNA sequencing. All isolates were initially screened for antimicrobial activity, and selected isolates underwent in vitro assessment of probiotic properties.ResultsAmong the lactobacilli isolates, varying levels of activity (9 to 19 mm) against cattle mastitogens; Stapylococcus aureus (Staph. aureus), Escherichia coli (E. coli) and Streptococcus dysgalactiae (Strep. dysgalactiae) were observed in the well diffusion assay. These isolates demonstrated auto-aggregation (ranging from 14.29 ± 0.96% to 62.11 ± 1.09%) and co-aggregate (ranging from 9.21 ± 0.14% to 55.74 ± 0.74%) with mastitogens after 2 h. Lactobacillus (Lb.) plantarum CM49 showed sensitivity to most antibiotics tested and exhibited strong inhibitory effects, with mean log10 reductions of 3.46 for Staph. aureus, 2.82 for E. coli, and 1.45 for Strep. dysgalactiae in co-culture experiments. Furthermore, Lb. plantarum CM49 significantly decreased the adhesion rate of mastitogens on the bovine mammary cell line and mouse model, demonstrating its potential effectiveness in preventing mastitis.ConclusionIt is concluded that Lb. plantarum CM49 has remarkable probiotic potential with activity against cattle mastitogens in the laboratory and cell culture and competitively excludes mastitogens from bovine mammary cells and ameliorates Staph. aureus-induced mastitis in mice.

Exploring probiotic potential and antimicrobial properties of lactic acid bacteria from cow's milk

One of the most important foods in the world is milk, due to its nutrients and composition. Milk also contains lactic acid bacteria (LABs), which can produce antimicrobial compounds and organic acids; an essential factor in developing different methods to control other bacteria. Another critical factor is that several species of LABs are considered potential probiotics, offering several health benefits. This study aimed to isolate, identify LABs, characterize the antimicrobial susceptibility profile, and evaluate the inhibition potential against Staphylococcus aureus (ATCC 25923), Listeria monocytogenes (ATCC 7644), Escherichia coli (ATCC 25922) and Salmonella Typhimurium (ATCC 14028); as well as verifying the acidification capacity, survival of simulated in vitro gastrointestinal conditions and identification of virulence genes and bacteriocin-producing genes. The study was carried out with LABs previously isolated from milk of cows with clinical mastitis, low and high (Somatic Cells Count) in herds from all regions of Brazil (South, Southeast, Central-West, North, and Northeast). One hundred and ten strains were selected for identification using the MALDI-TOF technique. The genera with the most significant spectrum of action were Lactococcus, Lactobacillus, and Pediococcus in the antimicrobial action test against pathogens, concluding that Lactobacillus showed resistance to several antibiotics. The analysis of antimicrobial action made it possible to verify the potential production of antimicrobial compounds by LABs against the primary pathogens of food origin. The most significant reduction in pH could be observed from 24 h to 48 h, ranging from 6.8 (0 h) to 4.74 (48 h) for Lactobacillus and Lactococcus. All isolates survived tolerance tests at pH=3.0 and bile salts (0.5 %), with survival rates ranging from 34.2 to 69.9 % at pH = 3.0 and above 82 % at 0.5 % bile salts. Lacotococcus and Lactobacillus isolates presented the plnEF and plnNC8 genes. This study contributes to the search for alternatives in the treatment of bacterial infections with a reduction in the use of antibiotics, which, due to the increase in bacterial resistance, is causing difficulties in treating diseases caused by these microorganisms. pH is an important parameter when it comes to food safety and conservation. Tolerance to acid stress and bile salts are important properties in evaluating probiotic potential and the ability to maintain high counts under these conditions. The presence of the plnEF and plnNC8 genes suggests bacteriocin production.

Isolation and Molecular Characterization of Therapeutic Probiotic Lactobacillus from Different Sources in Ernakulam-Kerala

This study aims to present knowledge on therapeutic potential bacteriocin producing bacterial strains. Samples (n=35) from diverse Ernakulam sources yielded 26 lactic acid bacteria (LAB) isolates on De Man Rogosa Sharpe (MRS) medium. Among the isolates potent antimicrobial activity observed against known pathogens in one of the isolates from goat milk sample number 3, labelled as GO3. Microscopic and biochemical test revealed the isolate is Gram-positive rod, non-sporulating and resilience to pH and bile salts, with adaptability to gastric enzymes and surfactants. Genetic and physiological traits of the positive strains were confirmd by 16S rRNA technique. Blast analysis revealed that sequence of the strain GO3 from goat milk identified as Lactobacillus casei, exhibited antibiotic sensitivity, auto-aggregation, co-aggregation, and antibiofilm assays highlighted inhibitory properties as a promising therapeutic potential probiotic bacterium. LAB isolates can be further investigated at the genetic level to enhance their probiotic characteristics such as resistance and cellular adhesion. Additionally, the identification of gene responsible for expressing bacteriocins can be conducted on these isolates.

Isolasi dan karakterisasi bakteri asam laktat dari susu sapi di Indonesia

Cow's milk is a source of nutrition that has a good impact on health and contains a variety of microorganisms, one of which is lactic acid bacteria (LAB) such as Streptococcus thermophilus and Lactobacillus sp. Therefore, this study aimed to isolate and characterize LAB from the milk of Friesian Holstein dairy cows in Indonesia. In addition, BAL enumeration was carried out to determine the population of LAB in cow's milk samples. Based on the results obtained, as many as 4.36 log CFU/mL of LAB was successfully enumerated in the sample. Cell morphology observations showed that there were 15 Streptococcus, and 35 Lactobacillus candidate isolates which were Gram positive, did not form endospores, and did not have a wax coating on their cell walls. Furthermore, negative results of the catalase test were shown by 10 Streptococcus and 35 Lactobacillus candidate isolates. Carbohydrate fermentation test showed that isolate STRP1 and STRP4 were suspected to be Streptococcus sp., while the Lactobacillus isolates were possibly L. delbrueckii, L. acidophilus, and L. helveticus. The hemolytic test indicated that STRP1 is S. thermophilus with alpha hemolytic activity. Confirmation of the species of the isolates should be done through molecular identification and further characterization.

THE SYNERGISTIC EFFECTS OF LIPOPEPTIDES AND BACTERIOCINS PRODUCED BY Lactobacillus sp. OF HUMAN SAMPLES AGAINST CLINICAL PATHOGENS OF WOUND INFECTION

This study was performed for production, purification, characterization and evaluation the antibacterial activity of biosurfactant BS which were produced from local isolate Lactobacillus plantarum Z9 with bacteriocin and studying the synergistic effect .A total 100 different samples 85(%) isolates of Lactobacillus sp. were isolated from different sources and identified by biochemical tests then subjected to the primary and secondary screening processes to select the active isolate for bacteriocin and biosurfactant production. Among the vagina isolates screened, the results found that Lactobacillus sp. Z9 isolated from the clinical samples of Iraqi healthy women had the highest productivity of the bacteriocin and biosurfactant. Partial purification of biosurfactant that produced from L. plantarum Z9 was conducted using solvent system (chloroform: methanol, 2:1). A 1:1 ratio of n-butanol was used to extract of partially purified bacteriocin, where the bacteriocin activity up to 320 AU/ml against both Staphylococcus aureus and Pseudomonas aeruginosa respectively compared to 20 AU/ml before purification.. Antibacterial activity of Bacteriocin displayed a significant activity with inhibition zones diameter ranged from (11 to 26 mm) and (10 to 25 mm) against P. aeruginosa and S. aureus at concentration ranged from 50 to 200 mg/ml. Maximum antibacterial activity of bacteriocin against P. aeruginosa and S. aureus showed at concentration 200 mg/ml of bacteriocin. Partial purified lipopeptide of L. plantarum Z9 was examined against pathogenic bacteria using well diffusion method. The lipopeptide had inhibition zones diameter ranged from (14 to 28 mm) and (13 to 29 mm) against P. aeruginosa and S. aureus respectively at concentration ranged from 25 to 200 mg/ml. The combination of lipopeptide with bacteriocin increased the range of inhibition zones and made the pathogens sensitive.

Isolation of Lactobacillus plantarum CMT1 from shrimp intestine and its effects on growth and survival of the whiteleg shrimp, Litopeneaus vannamei

Probiotics are widely applied in aquaculture, which can improve the growth, survival and health of aquatic animals. The aim of this study was to isolate and evaluate a Lactobacillus strain from the intestine of healthy whiteleg shrimp, Litopenaeus vannamei. A total of 20 Lactobacillus isolates showed rod-shaped morphology, gram-positive, non-motile, non-spore forming, and catalase and oxidase negative. Among the isolates, strain CMT1 exhibited the highest antibacterial activity against Vibrio parahaemolyticus and extracellular enzyme activity, which was selected and identified as Lactobacillus plantarum CMT1 based on 16S rDNA gene sequencing. This strain was also chosen to evaluate its effects on growth and survival of the whiteleg shrimp as a feed supplement. Four different diets were prepared, including the control (a commercial diet without L. plantarum CMT1) and three different concentrations of L. plantarum CMT1, viz. T1 (106 CFU kg diet-1), T2 (107 CFU kg diet-1), and T3 (108 CFU kg diet-1). After a 56-day feeding trial, the growth parameters in the T3 group had the highest values and showed a significant difference compared to the other groups. The survival rates of shrimp fed T2 and T3 diets were significantly higher than those in the control diet (p < 0.05). The lowest FCR value was recorded in the T3 group and showed a significant difference compared to the control group (p < 0.05). In addition, Lactobacillus counts in T2 and T3 groups increased significantly from day 28, which indicated that L. plantarum CMT1 could sustain its population in the intestine of shrimp. However, the total Vibrio sp. count in the T2 and T3 groups was significantly lower than that in the control group (p < 0.05). In conclusion, L. plantarum CMT1 could be used as a potential probiotic for shrimp aquaculture, and the recommended level of the probiotic strain CMT1 is 108 CFU kg diet-1.

Probiotic Abilities of Lactobacillus spp. Isolated from Algerian Fermented Wheat ‘Hamoum’ intended to Use in Broiler Production

Background: The use of probiotics has become popular in the broiler poultry industry due to its positive results on the health of animals, as well as the safety of consumers. In general, probiotics are isolated and selected In vitro from several sources. Despite this, only a few studies focused on isolating probiotics from cereals, which are the main natural food source for poultry. This study aimed to evaluate and identify an autochthonous Lactobacillus spp. isolated from Algerian fermented wheat “Hamoum” as potential probiotics for use in broiler feed. Methods: This research was conducted over the period between 2019-2022. Five bacterial isolates of the genus Lactobacillus were tested for their hemolysis activity, exopolysaccharides production, the ability to withstand the simulated hostile conditions of the chicken’s gut and their capacity to acidify the concentrate feed beverage. Finally, molecular identification was performed using the REP-PCR technique. Result: These isolates were found to produce exopolysaccharides and have no hemolytic activity. Also, could tolerate simulated gastric acidity. However, only three isolates were able to survive in the presence of bile salts and were found to have a high capacity for acidifying medium in a relatively short time. These isolates were identified as Lactobacillus acidophilus and Lactobacillus plantarum subsp plantarum. Those strains can be considered safe candidate probiotics for use in broiler feeds feed. Further studies are needed to investigate and evaluate the effectiveness of these isolates through an in vivo experiment on broiler chickens.

Formulation and Cell Viability Assessment of Microparticles of Isolated Lactobacillus sp. with Alginate-Chitosan Solution

This study was performed to isolate the probiotic Lactobacillus sp. from dairy products available in Dhaka to form microparticles with isolated Lactobacillus probiotic bacteria and determine cell viability. Depending on their biological and physical traits and selective growth in MRS agar and MRS broth medium, the isolates were recognized as Lactobacillus spp. Major biochemical tests and growth at different temperatures were taken into account for the identification of the isolates. Low pH tolerance, homo- or hetero-fermentative activity, hydrolysis of arginine, and antibiotic susceptibility tests were conducted to assess probiotic activity. Among several isolates of Lactobacillus sp., four showed considerable tolerance to lower pH (pH 3.0) and growth at different temperatures (15 to 37°C). They were resistant to common antibiotics like penicillin (10µg), gentamicin (30µg), tetracycline (30µg), chloramphenicol (30µg), erythromycin (15µg) and streptomycin (30µg). The isolates were shown to have superior probiotic capabilities and may be employed as possible probiotic microorganisms after comparing all probiotic features evaluated in this experiment. The capacity of probiotic bacterial cells to survive when stored and in gastrointestinal transit is difficult to maintain. As a solution to these obstacles, microparticles were formulated with sodium alginate and chitosan. The cell viability check of the microparticles was continued for two weeks, and the response positively indicated increased stability. The results show promise for the encapsulation of the isolates. Jagannath University Journal of Life and Earth Sciences, 9(1): 69–80, 2023 (June)

Antibacterial potential of lactic acid bacteria isolated from raw cow milk in Sylhet district, Bangladesh: A molecular approach.

The most prevalent probiotic bacterium employed in the food industry is Lactobacillus because it can produce metabolites with antibacterial capabilities and exhibits hostility towards infections and microorganisms that cause spoilage. This study set out to identify naturally occurring Lactobacillus and plantaricin (pln EF) coding genes in raw cow milk and to assess the antibacterial potency of isolated Lactobacillus isolates. Following enrichment in De Man, Rogosa and Sharpe (MRS) broth, single colonies were isolated, and pure colonies were obtained by streaking on MRS agar. The 16S rRNA gene was amplified using polymerase chain reaction (PCR) to confirm the cultural positivity of all isolates. Additionally, the presence of plantaricin was verified by targeting the pln EF gene through PCR. Out of the 166 raw milk specimens acquired from cows, 153 (91.17%; CI: 86.98-95.76) were identified as positive for Lactobacillus through both culture and biochemical screening. Subsequently, 121 (72.89%; CI: 65.46-79.49) of the isolates were affirmed to harbour Lactobacillus through PCR analysis. Within this subset, 6 isolates (4.96%; CI: 1.84-10.48) were found to possess the plnEF gene. When exposed to Lactobacillus isolates, Salmonella Typhimurium and Salmonella enterica displayed an average maximum zone of inhibition with a diameter measuring 24mm. In contrast, Escherichia coli exhibited an average minimum zone of inhibition, featuring a diameter of 11mm. Additionally, the Lactobacillus isolates demonstrated inhibitory zones against Staphylococcus aureus, Klebsiella pneumoniae and Klebsiella oxytoca, measuring 14, 22 and 19mm, respectively. Lactic acid bacteria, particularly Lactobacilli, are plentiful in cow milk and possess broad-spectrum antibacterial properties.

Antimicrobial and Probiotic Potential of Lactobacilli Associated with Traditional Fermented Beverages.

Fermented foods have been recognized as a source of probiotic bacteria which can have a positive effect when administered to humans and animals. Discovering new probiotics in fermented food products poses a global economic and health importance. In this study, we investigated the antimicrobial and probiotic potential of lactobacilli isolated from fermented beverages produced traditionally by ethnic groups in Northeast India. Out of thirty Lactobacilli, fifteen exhibited strong antimicrobial activity against Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter aerogenes with significant anti-biofilm and anti-quorum sensing activity. These isolates also showed characteristics associated with probiotic properties, such as tolerance to low pH and bile salts, survival in the gastric tract, auto-aggregation, and hydrophobicity without exhibiting hemolysis formation or resistance to certain antibiotics. The isolates were identified using gram staining, biochemical tests, and 16S rDNA sequencing. They exhibited probiotic potential, broad-spectrum of antibacterial activity, promising anti-biofilm, anti-quorum sensing activity, non-hemolytic, and tolerance to acidic pH and bile salts. Overall, four specific Lactobacillus isolates, Lactiplantibacillus plantarum BRD3A and Lacticaseibacillus paracasei RB10OW from fermented rice-based beverage, and Lactiplantibacillus plantarum RB30Y and Lacticaseibacillus paracasei MP11A from traditional local curd demonstrated potent antimicrobial and probiotic properties. These findings suggest that these lactobacilli isolates from fermented beverages have the potential to be used as probiotics with therapeutic benefits, highlighting the importance of traditional fermented foods for promoting gut health and infectious disease management.

The Effect of a Direct Fed Microbial on Liveweight and Milk Production in Dairy Cattle.

This longitudinal study aimed to quantify the effects of dietary supplementation of a direct-fed microbial (DFM) consisting of three lactobacilli isolates on milk yield, milk fat and protein yields, somatic cell count (SCC), and liveweight in a single dairy herd in Australia. A total of 150 dairy cows were randomly selected based on parity and days in milk and divided into two groups: control (n = 75) and DFM treatment (n = 75). Throughout the study, the two groups of cows were housed separately in a dry lot yard, and each group had their own feeding area. For the DFM treatment group, selected cows in mid-lactation were supplemented with 10 mL/cow/day of the DFM via top dressing of the feed for the remainder of the lactation and through the dry period, extending into subsequent lactation. The control group had no supplementation. The milk yield and liveweight were recorded daily. Milk samples were collected every two months for milk component analysis (fat, protein, and somatic cell count [SCC]). The DFM-treated cows gained more liveweight across the study (19.40 kg, 95% CI 0.44 kg; 38.30 kg, p = 0.05) compared to the control cows. In the second production year, the DFM-treated cows mobilized more liveweight (-6.06 kg, 95% CI -10.49 kg; -1.61 kg, p = 0.01) and produced more milk (0.39 L/d 95% CI 0.10; 0.89, p = 0.05). Over a full lactation, DFM cows yielded at least 258 L (95% CI 252 L; 265 L) more milk than controls. No significant differences were found in fat and protein yield or SCC. This study suggests that consistent and ongoing supplementation with a Lacticaseibacillus- and Lentilactobacillus-based DFM could have a positive effect on milk production, but further research is needed to understand the underlying mechanism.

Isolation and identification of probiotic lactobacilli from ruminant animals

Background Lactobacillus strains are a group of bacteria that provide health benefits to their hosts when consumed in proper amounts. They are which exhibit an important for intestinal microflora that constitutes a beneficial mechanism responsible for antimicrobial activity. Ruminant animals such as cattle, buffalo, goat, and sheep have formed a symbiotic relationship with ruminal microorganisms that synthesize fiber digesting enzymes. The microbial flora obtained from ruminal ingesta is an output of the composition, nature, and quality of the animals’ feed. It is found that the dominating flora are usually starch and complex polysaccharide degrading microbiota. Objective The aim of the present study was to isolate and identify probiotic lactobacilli present in some ruminant animals to investigate interspecies differences in probiotic Lactobacillus contents. Materials and methods Sixty samples were collected in triple manner under aseptic conditions from buffalo, cattle, sheep and goats including rectal, buccal, and nasal swabs. Following DNA extraction from the isolated bacteria, 16S rRNA multiplex polymerase chain reaction analysis was performed to recognize the obtained isolates. Results and conclusion A total of 38 isolates were identified as lactobacillus species including 7, 14, 8, and 9 isolates from buffalo, cattle, sheep, and goat, respectively. The buffalo samples displayed the lowest variability in lactobacilli with the identification of Lactobacillus delbrueckii only. Cattle, goat, and sheep samples showed the presence of Lactobacillus casei, Lactobacillus acidophillus, L. delbrueckii, Lactobacillus gasseri, and Lactobacillus rhamnosus. It is found that L. gasseri was the most frequently isolated species in cattle followed by L. rhamnosus, while L. delbrueckii was the most frequently isolated species in goat followed by L. casei. L. gasseri was the most frequently isolated strain in sheep followed by L. acidophillus and L. rhamnosus. These strains should be investigated in more detail, individually or in combination, for their potential health benefits. Understanding how these species interact with other microbiota community members in each host as well as how they interact with host cells, particularly immune cells, can provide valuable insight into their function both in health and disease.

Isolation of Lactobacilli from Freshly Drawn Raw Milk of Desi and Crossbred Cows of Gurugram Region, Haryana

Isolation of Lactobacilli from Freshly Drawn Raw Milk of Desi and Crossbred Cows of Gurugram Region, Haryana

Preliminary Study on the Identification of Aerobic Vaginitis by Artificial Intelligence Analysis System

To develop an artificial intelligence vaginal secretion analysis system based on deep learning and to evaluate the accuracy of automated microscopy in the clinical diagnosis of aerobic vaginitis (AV). In this study, the vaginal secretion samples of 3769 patients receiving treatment at the Department of Obstetrics and Gynecology, West China Second Hospital, Sichuan University between January 2020 and December 2021 were selected. Using the results of manual microscopy as the control, we developed the linear kernel SVM algorithm, an artificial intelligence (AI) automated analysis software, with Python Scikit-learn script. The AI automated analysis software could identify leucocytes with toxic appearance and parabasal epitheliocytes (PBC). The bacterial grading parameters were reset using standard strains of lactobacillus and AV common isolates. The receiver operating characteristic (ROC) curve analysis was used to determine the cut-off value of AV evaluation results for different scoring items were obtained by using the results of manual microscopy as the control. Then, the parameters of automatic AV identification were determined and the automatic AV analysis scoring method was initially established. A total of 3769 vaginal secretion samples were collected. The AI automated analysis system incorporated five parameters and each parameter incorporated three severity scoring levels. We selected 1.5 μm as the cut-off value for the diameter between Lactobacillus and common AV bacterial isolates. The automated identification parameter of Lactobacillus was the ratio of bacteria ≥1.5 μm to those <1.5 μm. The cut-off scores were 2.5 and 0.5, In the parameter of white blood cells (WBC), the cut-off value of the absolute number of WBC was 103 μL－1 and the cut-off value of WBC-to-epithelial cell ratio was 10. The automated identification parameter of toxic WBC was the ratio of toxic WBC toWBC and the cut-off values were 1% and 15%. The parameter of background flora was bacteria<1.5 μm and the cut-off values were 5×103 μL－1 and 3×104 μL－1. The parameter of the parabasal epitheliocytes was the ratio of PBC to epithelial cells and the cut-off values were 1% and 10%. The agreement rate between the results of automated microscopy and those of manual microscopy was 92.5%. Out of 200 samples, automated microscopy and manual microscopy produced consistent scores for 185 samples, while the results for 15 samples were inconsistent. We developed an AI recognition software for AV and established an automated vaginal secretion microscopy scoring system for AV. There was good overall concordance between automated microscopy and manual microscopy. The AI identification software for AV can complete clinical lab examination with rather high objectivity, sensitivity, and efficiency, markedly reducing the workload of manual microscopy.

Probiotics screening from selected Nigerian prebiotics: Alternative starter culture sources for yoghurt production

The rise of functional foods has expanded food production, offering not just essential nutrition but also potential health and longevity benefits. This study aimed to identify probiotics from common Nigerian fermented foods as potential starter cultures for yogurt production. Ten local fermented food were screened for suitable starter culture(probiotics) for yogurt production, including fresh milk from cow (CM), sheep (SM), and goat (GM), as well as pap made from maize, millet, sorghum, cassava products (garri, fufu, and lafun), and Kunuzaki. Probiotic isolates with desired characteristics underwent tests for tolerance to acidic pH and bile conditions; antioxidative properties. Test yogurt was produced using Lactobacillus (LAB) isolates and physicochemical and organoleptic scores were determined for the yogurt samples. LAB species from CM, SM, and Lafun samples showed tolerance to both acidic pH (pH 3.0) and 0.5 percent bile. CM isolates exhibited strong antioxidant effects comparable to vitamin C. Yogurt samples had pH ranging from 4.77 to 5.45 and titratable acidity from 5.56 to 8.06. Sensory characteristics of the test yogurt did not significantly differ from commercial yogurt (p ≤ 0.05). Thus, probiotics (LAB) from common Nigerian fermented foods like CM, SM, and lafun could serve as cost-effective, nutrient-rich alternatives for yogurt starter cultures.

Investigation of vitality, antibacterial properties, and antagonistic effects of probiotic bacteria in probiotic dairy products

Probiotics play a significant role in the diet, and their contribution to the immune system has been recognised. Their effects on the gastrointestinal system have been evaluated for decades, and the mechanisms of the effects may differ. The aim of the present work was (i) to observe the changes in pH and bacterial counts in common probiotic dairy products, (ii) to isolate probiotic bacteria, (iii) to evaluate antibacterial resistance, and (iv) to evaluate their metabolites' antibacterial effects against common foodborne pathogens. To this end, 20 dairy products labelled "probiotics included" were collected. Isolation and enumeration of Lactobacillus spp., L. acidophilus, and Bifidobacterium spp. were carried out using de Man-Rogosa-Sharp agar (MRS), clindamycin/ciprofloxacin-included MRS agar (MRS-CC), and mupirocin (MUP) supplemented Bifidobacterium selective count agar (BSC-MUP), respectively. Isolates were identified using MALDI-TOF MS analyses, enumerated, and evaluated for their pH values at 1 to 28 d after production, at 1-w intervals. Selected isolates were analysed for antibacterial resistance using the disc diffusion method. Supernatants were then collected from selected probiotics grown in broth, and studied for their antagonistic effects against pathogens using disc diffusion and agar-well diffusion tests. IBM SPSS software was used for statistical analyses. Tests of normality and non-parametric analyses were performed. On the last day of analyses, 75% of the products met the probiotic bacteria vitality requirement of 106 CFU/g. Statistical analyses showed no correlation between increased acidity and bacterial decrease (p &gt; 0.05), while the decrease in pH and bacterial count had significant relationship (p &lt; 0.05). All selected isolates of probiotic bacteria (n = 10) showed multi-drug resistance (MDR) to 10 different common antibiotics. Antagonistic effects were present but weak (inhibition zones were 0 - 4 mm in diameter). When consumed in sufficient amounts, probiotics may inhibit possible pathogen growth in the gut microbiota via metabolites.