Francesco Marotta

Molecular approaches for identification and characterization of lactic acid bacteria

The last few years have produced a revolution in the development of very sensitive, rapid, automated, molecular detection methods for a variety of various species of lactic acid bacteria (LAB) associated with food and dairy products. Nowadays many such strains of LAB are considered probiotics. The genome‐based methods are useful in identifying bacteria as a complementary or alternative tool to phenotypical methods. Over the years, identification methodologies using primers that target different sequences, such as the 16S ribosomal RNA (rRNA)‐encoding gene, the 16S‐23S rRNA intergenic spacer region, the 23S rRNA‐encoding, recA and ldhD genes; randomly amplified polymorphic DNA, restriction fragment length polymorphism, denaturing gradient gel electrophoresis, temperature gradient gel electrophoresis, amplification rDNA restriction analysis, restriction enzyme analysis, rRNA, pulse field gel electrophoresis and amplification fragment length polymorphism have played a significant role in probiotic bacteriology. Hence, the aim of this review is to provide an overview of some rapid and reliable polymerase chain reaction‐based molecular methods used for identifying and differentiating closely related species and strains of LAB associated with food and industry.

Dahi containing probiotic Lactobacillus acidophilus and Lactobacillus casei has a protective effect against Salmonella enteritidis infection in mice.

Salmonella enteritidis infection has received attention during recent years owing to its high prevalence worldwide. In the present study, the protective effect of probiotic dahi (curd) supplemented with Lactobacillus acidophilus and L. casei against Salmonella enteritidis infection in mice is investigated. Seven days pre-feeding with probiotic dahi significantly increased anti-S. enteritidis sIgA (secretary IgA) antibodies and lymphocyte proliferation in S. enteritidis infected mice. IL-2, IL-6 and IFNγ production were significantly increased in supernatant of cultured splenocytes collected from mice pre-fed with probiotic dahi, while IL-4 levels were not changed significantly. Moreover, activities of β-galactosidase and β-glucuronidase, and counts of S. enteritidis in intestine, liver and spleen were decreased, whereas total lactobacilli in faeces were increased in mice pre-fed with probiotic dahi. Pre-feeding of probiotic dahi for 7 days was more effective than 2 days pre-feeding. Thus, the results indicate that, pre-feeding with probiotic dahi ameliorated S. enteritidis infection by stimulating specific and non-specific immune response. Above all, it lowered colonization of gastrointestinal tract as well as translocation of S. enteritidis.

Antimicrobial Property of a Herbal Preparation Containing Dalbergia Sissoo and Datura Stramonium with Cow Urine against Pathogenic Bacteria

In this study, a herbal preparation containing Dalbergia sissoo and Datura stramoium with cow urine (DSDS), was evaluated for its antibacterial potential against pathogenic strains of gram-positive (Staphylococcus aureus and Streptococcus pneumoniae) and gram-negative (Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae) bacteria. Antibacterial activity was compared to standard antibiotic drugs i.e. Chloramphenicol (30 mcg), Ampicillin (10 mcg), Nalidixic acid (10 mcg) and Rifampicin (30 mcg). Cow urine extract was found to be most active against both gram-positive as well as gram-negative bacteria. Clinical isolate of S. aureus showed higher sensitivity towards cow urine extract of DSDS than standard strains, and inhibited growth on most regulatory levels such as inhibition of protein, DNA, RNA and peptidoglycan synthesis. The results of the present study shows that the cow urine extract of DSDS may be used as a potent antiseptic preparation for prevention and treatment of chronic bacterial infections.

Probiotics Mediated Modulation of Gut-Flora Might Be a Biotherapeutical Approach for Obesity and Type 2 Diabetes

these evidences doesn’t exclude the differential efficacy of probiotics in human subjects, hence very well controlled/ designed studies are urgently needed to check the efficacy of probiotics in human health against obesity and diabetes. A deeper knowledge of our gut ecology will be mandatory in the hope to target much more specific probiotic intervention. In this regards it is of interest the recent intriguing review from Rastmanesh [13] suggesting that a high-polyphenol and selectively-restricted probiotic diet could represent a novel strategy for planning a successful dietary regimen and/or neutraceutical/ pharmaceutical preparations to achieve and maintain a normal body weight in obese individuals. Overall, such studies will also give opportunities to industries to think about the risk vs safety of probiotic formulations for obesity and diabetes in consumers, worldwide.

Probiotics and Prebiotics for Promoting Health: Through Gut Microbiota

The human gut harbors approximately 100 trillion bacteria. Sustaining a perfect ratio of “good bacteria” to “bad bacteria” has gained tremendous recognition in recent years as a potential step in maintaining good health and preventing myriad gut- and metabolism-associated ailments, including obesity, metabolic syndrome, inflammatory bowel disease, and more. Probiotics have gained growing popularity in the past two decades because of their beneficial health effects backed by abundant scientific evidences. The proposed favorable effects of probiotics on human health include amelioration of gastrointestinal health, improvement of lactose intolerance, and reduced risk of various other gut- and metabolism-associated maladies. Various probiotic strains, especially Lactobacilli and Bifidobacteria , are now commercially accessible for human use. However, the characteristics of probiotic strains and their function, efficacy, and safety in relation to the gastrointestinal health and environment remains to be fully elucidated, and therefore needs to be further explored. In this context, this chapter attempts to review the available literature on potential probiotics and prebiotics, and their health benefits.