Lactobacillus plantarum, Lactobacillus casei, local proteolytic strains evaluated for their probiotic potential (original) (raw)
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Characterization of probiotic properties of Lactobacillus strains
Dairy Science and Technology, 2008
The objectives of this study were to demonstrate the gastro-intestinal tolerance and the capacity to modulate the intestinal microbiota of some Lactobacillus acidophilus, L. casei and L. rhamnosus strains with high probiotic potential. L. acidophilus and L. casei mixture that is used to produce probiotic fermented milk has been evaluated for its acid resistance and bile salts tolerance and compared to other lactic acid bacteria (LAB). The commercial culture and the three strains of L. rhamnosus exhibited complete tolerance to acid for pH ≥ 2.5. The minimal inhibitory concentration of the bile salts mixture was 50 g•L −1 for all bacteria. The impact of the ingestion of the novel probiotic on the fecal microbiota was evaluated in vivo using healthy C57Bl/6 mice. Fecal samples were analyzed for the microbiota enumeration using selective plating. Fecal analysis showed an increase of total culturable LAB and a decrease in Staphylococcus spp. population in the LAB-treated mice indicating that these cultures could improve the intestinal health. Also, reduction in fecal Enterobacteriaceae was noticed following mice gavage with L. rhamnosus ATCC 9595 while a higher enumeration was measured for L. rhamnosus RW-9595M, an exopolysaccharideoverproducing mutant. These contradictory results were discussed.
Journal of Pure and Applied Microbiology, 2017
The objective of this study was to isolate and select Lactobacillus strains with probiotic features for a potential use as starter for the preservation of animal feed. Olives, cow's and camel's milk, butter, beer drech and maize silage were used as isolation sources. Molecular identification using 16S rRNA gene sequencing identified four isolates of Lactobacillus plantarum and three of Lactobacillus fermentum. The different screening tests revealed that four strains: Lactobacillus plantarum OV13, Lactobacillus sp. OV15, Lactobacillus fermentum E161 and Lactobacillus sp. E631 are the best probiotic candidates , based on the results of their tolerance to acidic pH between 2 and 3.5, to 0.3% bile, to artificial gastric conditions for 18h of incubation , to their antibiotics resistance, their inhibition power on pathogenic bacteria (Pseudomonas sp., Staphylococcus aureus , Escherichia coli and Listeria ivanovii), and finally to their adhesion capacity to intestinal epithelial cells. The selected probiotic strains are considerate as good candidates for further investigation and should be tested, in vivo, to elucidate their potential health benefits on the animal performance as novel probiotic starters.
Lactobacillus strains are a major part of the probiotics, microflora of the intestine as well as of fermented dairy products, and are found in a variety of environments. The aim of this study was to find out the ability of bile salts and acid tolerance as well as antibacterial properties of the three lactobacillus strains namely Lactobacillus acidophilus ATCC 20552, Lactobacillus casei DSM 20011 and Lactobacillus plantarum ATCC 14917. The acid tolerance test was studied under pH 2.0 and 3.0 with 6.5 as a control. The cell count for the acid tolerance test was obtained at an interval of 0, 1, 2 and 3 hours, and was pour plated on Man Rogosa, and Sharpe (MRS) agar to be incubated at 37 °C for 24 hours. All cells were selected for bile tolerance test in MRS broth containing bile concentrations of 0 % as control and 0.1, 0.3, 0.5 and 0.7 % as test and antibiotic susceptibility. Results showed that the three strains of Lactobacilli have ability to tolerate acid and bile salts and resistance to 0.4 % of phenol and were susceptible for streptomycin (10 μg), ampicilline (10 μg), chloramphenicol (30 μg), erytromycin (15 μg), amoxicillin/clavulanic acid (30 μg) and rifampicin (5 μg). All strains have antimicrobial activity against seven indicator bacteria included Bacillus cereus DSM 351, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 12600, Listeria monocytogenes, Salmonella typhimurium ATCC14028, Klebseilla pneumonia ATCC 1705 and Pseudomonas aeruginosa ATCC 43495.
ijasre, 2019
Lactic acid bacteria are known to have probiotic attributes which are beneficial to human. This study was embarked upon to screen lactic acid bacteria (LAB)from raw milk and fermented milk (nono) samples for probiotic potential. Some of the assessed probiotic qualities include antimicrobial activities against foodborne pathogens, survival at acidic pH (2.5, 3.0) and bile salt concentrations (0.3%, 0.5%, 1.0%), safety test, and cell surface hydrophobicity assay indicative of epithelial adherence. Four LAB isolates namely Lactobacillus plantarumN17, L. plantarumN24, L. caseiN1 and L. brevisN10 had strong inhibition(10.00 to 15.15 mm) against selected foodborne pathogens, survived well at acidic pH and bile salt concentrations during 3 hours of incubation reaching viability of 105-106 CFU/mL. In addition, they were DNase and Gelatinase negative and had better(40.0 to 62.0 %) hydrophobicity indicative of epithelial adherence. Lactobacillus plantarumN24 and Lactobacillus caseiN1 were suitable probiotic candidates and can be used as for food supplements.
A total of 208 strains of lactic acid bacteria (LAB) were isolated from Algerian traditional fermented milk (Jben, Klila, Raib and Lben), in order to evaluate their technological and probiotic properties. These strains were tested for their antimicrobial activity against Listeria monocytogenes using agar well diffusion technique. Only 11 strains were retained, they were also characterised in respect to their technological properties. The retained strains were identified by analyses of the 16S rDNA gene as; Lb. curvatus (1 strain), Ln. mesenteroides subsp mesenteroides (1 strain),Lb. plantarum(3 strains), Lb. brevis (2 strain), Lactobacillus acidophilus (2 strains), andLactococcus lactissubsp lactis(2 strains). All the antimicrobial compounds produced by the selected lactic acid bacteria were fully or partially inactivated by the proteolytic enzymes. The compounds were heat stable up to 100°C for 20 min, and were active from pH 3.0 to 10.0. The enzymatic potential of the strains evaluated with API ZYM system show that all strains exhibited high leucine, cystine aminopeptidase and β-Galactosidase activities. Lactococcusstrains were those that showed the greatest degree of proteolytic activity, however very low lipolytic and amylolytic capacity was detected for same strains. Two out of the 11 selected strains showed moderate survival rates under simulated gastric, however all tested strains showed a high stability under intestinal conditions. According to the results, the selected LAB strains could be used as potential probiotics to a possible inhibition of food-borne pathogenic bacteria and also would be of considerable interest to use as starter culture.
Probiotic Properties of Some Lactic Acid Bacteria Isolated from Egyptian Dairy Products
The aim of this study was planned to evaluate probiotic properties of some lactic acid bacteria (LAB) previously isolated from fermented dairy products. These microorganisms had good functions potentially applicable in the dairy and food industries. To a chive this purpose eight strains as follows: hamnosus NRC AM-6, Lactobacillus plantarum NRC AM-7, Lactobacillus pentosus NRC AM-(5, 8), Pediococcus pentosaceus NRC AM-(1, 4), Lactobacillus brevis NRC AM2 (1 strain) and Lactoccocus lactis ssp. Lactis NRC AM-3 were screened in vitro for their probiotic traits, tolerance to bile salts, low pH resistance, growth and viability in different concentrations of NaCl and phenotypic safety assessment. The results indicated that survival (log cfu/ ml) of all tested strains were affected and gradually decreased from 4 to 5 log cycles with increasing the bile salts concentration to 1 % meanwhile, a good survival was observed with all tested strains under acidic conditions (pH 2) till 5 hrs of incubation time at 37oC but there was not any growth after 24 h. Also, no haemolytic activities ( -haemolysis) were observed for all tested strains.
Livestock Research for Rural Development, 2019
This paper describes the potential probiotic properties of a lactic acid bacterium. The evolution from a spontaneous fermentation to a directed one is realized with selected lactic starters which give many dairy products processing various organoleptic characters. The integration of new lactic acid bacteria strains isolated from diverse ecosystems is now used to increase the duration of bio-preservation of dairy products. Moreover, some lactic acid bacteria probiotic activity is exploited to produce functional food. The aim of this study is to research of the possible probiotic and technological potential with some preventive and therapeutic characteristics of some Lactobacillus species isolated from Algerian Raw Goat Milk. The selected isolate was identified to species level as Lactobacillus plantarum (58) using API 50CH Kits. Microbiological and biotechnological techniques were used to fulfill this work. Results obtained have shown that Lactobacillus plantarum (58) can resist to acidic, basic and enzymatic stresses. So, the former strain can be considered as a probiotic. Moreover, the inhibition activity of the Lactobacillus plantarum (58) against pathogens strains (Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25921, Bacillus cereus, Pseudomonas aeruginosa, Vibrio cholerae, Listeria ivanovii ATCC 19119 and Salmonella enterica) is clearly obtained by testing these strains with the direct method. Finally, Raw Goat Milk can be defined as an ecosystem that promotes the development of a microflora with probiotic characters.
Probiotic Potential of Lactobacillus plantarum Isolated from Zabady
Twenty one isolates of lactic acid bacteria (LAB) were isolated from Zabady, an Egyptian yoghurt, and screened for their antibacterial activities against 8 pathogens (Bacillus cereus ATCC 49064, Clostridium perfringens ATCC 13124, Escherichia coli, Listeria innocua ATCC 33090, Listeria monocytogenes ATCC 19116, Listeria ivanovii Li4 (pVS2), Salmonella enterica ATCC 25566, and Yersinia enterocolitica ATCC 23715) as indicator strains. One isolate was selected as a promising candidate.The selected isolate was identified as Lactobacillus plantarum by phenotypic and genotypic methods. Afterwards, the identified isolate was evaluated for a number of probiotic characteristics including tolerance to simulated gastric juice, bile salt resistance, cell surface hydrophobicity, resistance to low phenol concentration, autoggregation, coaggregation, adhesion to rabbit epithelial cells, and reduction of cholesterol. This isolate showed; sensitivity to simulated gastric juice adjusted at pH 2.0 - 3.5, tolerance to 0.3% bile concentration and antimicrobial activity against Salmonella enterica ATCC 25566 ((25600 Activity unit /ml), was Bacillus cereus ATCC 49064 (25600 Activity unit /ml), Yersinia enterocolitica ATCC 23715 (400 Activity unit /ml) and L. monocytogenes ATCC 19116 (200 Activity unit /ml) that is probably due to production of active peptides. Furthermore, the results demonstrate that this isolate was highly tolerated to different tested phenol concentrations, moderate cell surface hydrophobicity, weak autoaggregating and reasonable adhesion level to rabbit epithelial cell.
Characterization of Lactobacillus Isolates from Human Mouth and Feces as Probiotics
Characterization of Lactobacillus Isolates from Human Mouth and Feces as Probiotics, 2020
Probiotics are live microbes that give many health benefits to human beings and animals, the most studied and commonly used probiotics are Gram-positive bacteria; lactobacilli and bifidobacteria. At nowadays, Lactobacillus spp. constitute more than two-thirds of the total numbers of probiotic species. The present study aimed to characterize Lactobacillus that locally isolated from human mouth and feces as probiotics. A total of three Lactobacillus isolates; Lactobacillus fermentum Lb2, Lactobacillus rhamnosus Lb9, and Lactobacillus paracasei Lb10 were investigated in respect to acid and bile salts tolerance, antibiotics susceptibility, and cell surface hydrophobicity in vitro using bacterial adhesion to hydrocarbons method. In comparison with the other two isolates, the isolate L. fermentum Lb2 was able to grow in all pH values and in the presence of different concentrations of bile salts. Antibiotics susceptibility profile showed that the tested Lactobacillus isolates were sensitive to ampicillin, amoxicillin, and erythromycin, while they were resistant to the other antibiotics that used in this study. L. fermentum Lb2 exhibited high surface hydrophobicity (77.26%), while the other tested isolates; L. rhamnosus Lb9 and L. paracasei Lb10 revealed moderate adhesion abilities, 68.56% and 65%, respectively. L. fermentum Lb2 exhibited good probiotic behavior with respect to acid and bile salt tolerance as well as adhesion ability to hydrocarbons.
2019
Introduction: Lactobacilli are well-documented probiotics that exert health benefits on their host. They exhibit characteristics that make them potential alternative treatments to address the antimicrobial resistance conundrum and diseases. Their mechanism of action varies with strain and species. Five lactobacilli strains previously isolated from the anogenital region were subjected to several assessments highlighted in the FAO/WHO document, ‘Guidelines for the Evaluation of Probiotics in Food’ to determine its suitability as potential probiotics. Methods: The five lactobacilli strains were subcultured onto Man de Rogosa agar (MRS). Their ability to autoand co-aggregate was determined spectrophotometrically. Simultaneously, the cell surface hydrophobic properties of these strains towards xylene and toluene were evaluated using the microbial adhesion to hydrocarbon (MATH) test. The lactobacilli strains were also tested for their ability to withstand acid, bile and spermicide to dete...