Screening of Wild Lactic Acid Bacteria from Algerian Traditional Cheeses and Goat Butter to Develop a New Probiotic Starter Culture.

Twenty-five lactic acid bacterial (LAB) strains have been isolated from traditional goat butter and three types of cheese (dry Klila, frech Klila, and Bouhezza) and evaluated for technological abilities, probiotic properties, and potentials as starter cultures. The twenty-five LAB strains comprised eight strains belonging to Lactobacillus, four strains belonging to Lactococcus, eleven strains belonging to Enterococcus, and two strains belonging to Leuconostoc. A non-hierarchical cluster analysis was performed in order to select the performing strains. After carrying out the preliminary phenotypic characterizations and the probiotic potential, three strains designated as BM10, B15, and C30 belonging to the genus Lactobacillus and Enterococcus with good tolerance to acidity were selected. The strains showed a significant resistance to 0.5% bile salts and 0.4% phenol. Hemolytic activity was not detected; in addition, good hydrophobicity and autoaggregation was obtained. A significant antimicrobial activity was exhibited by all selected strains against Listeria innocua. Genotypic identification by 16S rRNA allowed the identification of B15, BM10, and C30 as Lactobacillus plantarum, Lactobacillus casei, and Enterococcus durans, respectively. The results of the current study suggest that the strains isolated from Algerian fermented dairy products have high potential as probiotic starter cultures in the goat butter and cheese industry.

The beneficial effects of virgin olive oil against oxidative stress induced by hypercholesterolemia in rats

Cardiovascular disease(CVD) remains the major cause of mortality in the world, typically claiming a third of all deaths. The primary cause of CVD is atherosclerosis. Therefore, timely prevention and therapy of atherosclerosis are able to reduce the risk of the development of its clinical manifestations. Anti-atherosclerotic activity of medicinal plants mainly appears in their multiple effects.This study was carried out to evaluate the hypolipidemic activity of virgin olive oil in experimentally induced hyperlipemic Wistar. A total of 24 rats were randomly allocated to 4 equal groups and treated as follows for 50 days: (1) Normal control (NC); that were fed with a standart diet; (2) High Cholesterol Diet Control (HCD); which received high cholesterol diet for 50 days; (3) Animals receiving high cholesterol diet for 50 days, after this period the animals are fed for eight days by the standard foodand receiving by gavage virgin olive oil (HCD+VOO) and(4) Animals fed for eight days with the standard food and receiving by gavage olive oil (VOO). High Cholesterol Diet containing yolk egg and coconut oil. Results showed that olive oil caused a significant (p < 0.01) reduction in serum levels of Total Cholesterol (TC), Triglycerides (TG), Low­Density Lipoprotein Cholesterol (LDL) and Atherogenic Index Serum (AIS). The results also demonstrated a significant (p < 0.01) increase in High­Density Lipoprotein Cholesterol (HDL). Moreover, virgin olive oil induced a significant reduction in liver lipid content. On the other hand, a High cholesterol diet induced oxidative stress was measured by estimating reduced glutathione level and amount of thiobarbituric acid reactive substances (TBARS) formed as an index of lipid peroxidation in a liver and a heart. Virgin olive oil supplementation attenuated all these variations. Our observations of the study indicate that the virgin olive oil has a significant antihyperlipidemic potential.

Enhancement of antioxidant properties of Triticum durum obtained by traditional spontaneous fermentation in underground silos

Fermented foods have made important contributions to human diets for thousands of years and continue to do so. Their health-promoting benefits are attracting increasingly attention. The present study was conducted to evaluate the impact of natural fermentation on antioxidant properties of traditionally fermented wheat (Triticum durum) compared to unfermented samples. Initially, the samples were submitted to traditional spontaneous fermentation. Subsequently, an aqueous extract was obtained and used to determine polyphenolic and flavonoid contents. Moreover, the antioxidant potential was also measured through the determination of the scavenging ability against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, reducing power and hydrogen peroxide scavenging activity. The results showed that the total phenolic and total flavonoid contents were significantly increased in fermented wheat. Moreover, the antioxidant activity was more effective in fermented than in unfermented wheat. Thus, natural fermentation can enhance natural antioxidants in wheat and transform it into a healthy food or ingredient with multi-functional properties which can be used in the food industry.

Bacteriocinogenic properties of Escherichia coli P2C isolated from pig gastrointestinal tract: purification and characterization of microcin V.

The aim of this study was to isolate and investigate the bacteriocinogenic and probiotic potential of new Gram-negative isolates. Of 22 bacterial isolates from pig intestine and chicken crops, ten isolates had demonstrated a good activity, and the most potent five strains were identified as four E. coli and one as Proteus sp. No virulence factors were detected for E. coli strains isolated from pig intestine. The semi-purified microcins proved to be resistant to temperature and pH variation, but sensitive to proteolytic enzymes. Of particular interest, strain E. coli P2C was the most potent, free of virulence genes and sensitive to tested antibiotics. Purification procedure revealed the presence of a single pure peak having a molecular mass of 8733.94 Da and matching microcin V (MccV). The sequence obtained by LC-MS/MS confirmed the presence of MccV. Purified MccV showed a good activity against pathogenic coliforms, especially E. coli O1K1H7 involved in avian colibacillosis. The present study provides evidence that E. coli strains isolated from pig intestine produce microcin-like substances. E. coli P2C is a safe MccV producer that could be a good candidate for its application as novel probiotic strain to protect livestock and enhance growth performance.

Technological and Probiotic Traits of the Lactobacilli Isolated From Vaginal Tract of the Healthy Women for Probiotic Use.

BACKGROUND: For biotechnological application, selected lactic acid bacteria strains belonging to the genera Lactobacillus (Lb) are proposed as an alternative to the antibiotics for the prevention and treatment of urogenital tract infections. OBJECTIVES: Isolating and selecting vaginal lactobacilli strains for probiotic use based on their technological and probiotic aptitudes. MATERIALS AND METHODS: The vaginal isolates were examined for their essential characteristics as the potential probiotic such as low pH tolerance, bile-salt and simulated human intestinal fluid (SIF) resistance, adhesion to the vaginal epithelial cells (VECs), aggregation and coaggregation, surface hydrophobicity, antimicrobial activity, acid production, antibiotic resistance, and resistance to spermicides. The best strain was identified by PCR. RESULTS: From 70 lactobacilli isolates and according to the 16 rDNA sequences, isolates B6 and B10 showed the closest homology (99%) to the Lb. gasseri and Lb. plantarum respectively. They produced hydrogen peroxide (H2O2), tolerant to acid, bile, simulated human intestinal fluid, present a strong adhesion, highest percentages of aggregation, and antibacterial activity. These strains are resistant to the spermicide and actively acidify the growth medium. CONCLUSIONS: Strains Lb. plantarum B10 and Lb. gasseri B6 have a strong potential probiotic confirming their value as a tool for prevention against urinary and vaginal infections.

Protective effects of probiotic Lactobacillus plantarum BJ0021 on liver and kidney oxidative stress and apoptosis induced by endosulfan in pregnant rats.

Endosulfan (EDS) is one of the most widely organochlorine insecticide used in many parts of the world, although it is currently banned or severely restricted in use in some countries. EDS causes a variety of negative effects in non-target species including humans. Therefore, the aim of the present study was to investigate the possible protective effects of Lactobacillus plantarum BJ0021 on toxicity, oxidative stress, and apoptosis induced by EDS intoxication on liver and kidneys of pregnant rats. This pesticide induced a significant increase in total cholesterol, alanine-amino transferase (ALAT), aspartate-amino transferase (ASAT), alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (GGT), urea and creatinine in serum, while urinary urea and creatinine were lower than those of the control group. In the liver and kidney, lipid peroxidation increased significantly, the antioxidant levels, such as superoxide dismutase (SOD) and catalase (CAT) were markedly depressed and TdT-mediated dUTP-biotin Nick End Labeling (TUNEL) revealed more apoptotic cells. In contrast, co-administration of L. plantarum BJ0021 to EDS-treated animals ameliorated most of these biochemical parameters, but the activity of antioxidant enzymes (SOD, CAT) did not modify and the number of apoptotic nuclei remained significantly raised in kidney compared to control. In conclusion, the administration of L. plantarum BJ0021 decreased apoptosis and might play a protective role in reducing toxicity of EDS in pregnant rats.

Protective effects of probiotic Lactobacillus plantarum BJ0021 on liver and kidney oxidative stress and apoptosis induced by endosulfan in pregnant rats.

Endosulfan (EDS) is one of the most widely organochlorine insecticide used in many parts of the world, although it is currently banned or severely restricted in use in some countries. EDS causes a variety of negative effects in non-target species including humans. Therefore, the aim of the present study was to investigate the possible protective effects of Lactobacillus plantarum BJ0021 on toxicity, oxidative stress, and apoptosis induced by EDS intoxication on liver and kidneys of pregnant rats. This pesticide induced a significant increase in total cholesterol, alanine-amino transferase (ALAT), aspartate-amino transferase (ASAT), alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (GGT), urea and creatinine in serum, while urinary urea and creatinine were lower than those of the control group. In the liver and kidney, lipid peroxidation increased significantly, the antioxidant levels, such as superoxide dismutase (SOD) and catalase (CAT) were markedly depressed and TdT-mediated dUTP-biotin Nick End Labeling (TUNEL) revealed more apoptotic cells. In contrast, co-administration of L. plantarum BJ0021 to EDS-treated animals ameliorated most of these biochemical parameters, but the activity of antioxidant enzymes (SOD, CAT) did not modify and the number of apoptotic nuclei remained significantly raised in kidney compared to control. In conclusion, the administration of L. plantarum BJ0021 decreased apoptosis and might play a protective role in reducing toxicity of EDS in pregnant rats.

Probiotic properties of Lactobacillus strains isolated from gizzard of local poultry.

BACKGROUND AND OBJECTIVE: The aim of our study was to characterize gizzard Lactobacillus fermentum-group strains on the basis of their phenotypic profiles regarding characteristics of lactobacilli. In addition, their in vitro potential probiotic properties were evaluated. MATERIALS AND METHODS: The lactic acid bacteria were isolated and identified from gizzard contents of Algerian local poultry using criteria of Bergey's Manual of Determinative Bacteriology and using methods and criteria of Sharpe. The strains were further characterized by tolerance to low pH and bile, coaggregation potential and adhesion to intestinal mucous. The antagonistic activity against some Enterobacteriaceae strains from poultry origin was also evaluated. RESULTS AND CONCLUSION: Among the strains identified, both physiological and biochemical characteristics differed noticeably. The strains coded LP3 and LP10 survived simulated gastrointestinal conditions and were considered to be acid and bile tolerant. The majority of the strains exhibited antagonistic activity towards Escherichia coli, Klebsiella spp., Enterobacter spp., Shigella spp., Salmonella spp and Citrobacter spp. The best co-aggregation properties were obtained with two isolates. Lb. fermentum LP3 alone showed adherence specificity to the chicken intestinal epithelium.