Probiotics have been considered as an economical and safe alternative for the treatment of a large number of chronic diseases and improvement of human health. They are known to modulate the host immunity and protect from several infectious and non-infectious diseases. The colonization, killing of pathogens and induction of host cells are few of the important probiotic attributes which affect several functions of the host. In addition, prebiotics and non-digestible food substances selectively promote the growth of probiotics and human health through nutrient enrichment, and modulation of gut microbiota and immune system. This review highlights the role of probiotics and prebiotics alone and in combination (synbiotics) in the modulation of immune system, treatment of infections, management of inflammatory bowel disease and cancer therapy. Key points • Probiotics and their derivatives against several human diseases. • Prebiotics feed probiotics and induce several functions in the host. • Discovery of novel and biosafe products needs attention for human health.

Background and Objectives: The purpose of the present study was to determine the microbial atmospheric contamination during initial periodontal treatment using a modern piezoelectric scaler and to evaluate the efficacy of two commercially available mouth rinses (0.2% Chlorhexidine mouth rinse and Listerine) in reducing bacterial contamination when used as a pre-procedural rinse, with and without high volume evacuation (Aerosol reduction device).

Objective- The objective of the present study was to investigate the effect of probiotic Lactobacillus casei Shirota on the values of mutans streptococci counts in saliva. Study design- 31 children were included in this double blinded study. Study design included 4 periods which consisted of a run in period, two intervention periods and a washout period. During the intervention periods children were either given probiotic milk or control milk for 10 days. Pre and post intervention salivary samples were subjected to microbiological evaluation. Then numbers of mutans streptococci were taken by identifying colony morphology. Results - A statistically significant reduction of mutans streptococci colony count was noted in the probiotic group (p=.003). The reduction in children with higher levels of mutans streptococci (105) after intervention was 34% in the probiotic group. Conclusion- Daily consumption of milk containing probiotic bacteria can reduce the levels of mutans streptococci and may contribute to the prevention of dental caries.

The colorimetric assay is phospholipid/polydiacetylene vesicle-based assay used for the detection of membrane-acting peptides. Bacteriocins and halocins are antimicrobial peptides known to kill target cells by membrane disruption. Therefore, the assay was applied for high-throughput (HTP) screening of bacteriocins and halocins produced by lactic acid bacteria and haloarchaea, respectively. The assay consisted of vesicles which were synthesized using four different phospholipids: dipalmitoylphosphatydilcholine (DPPC), dimyristoylphosphatidylcholine (DMPC), dimyristoylphosphoethanolamine (DMPE) and dimyristoylphosphatidylglycerol (DMPG) in combination with diacetylene monomer 10,12-tricosadiy noic acid (TRCDA). These vesicles demonstrated blue colour at 640 nm and turned pink/red after interaction with nisin. DMPE/TRCDA vesicles showed pink colour with the highest colorimetric response (CR %) after treatment with nisin and, therefore, selected for the screening of bacteriocins and halocins. The colour of the vesicles was changed within 5 min in the presence of 5 μM nisin suggesting the sensitivity of assay. The assay was applied on 54 strains of lactic acid bacteria (LAB) and 53 haloarchaea for screening of bacteriocins and halocins, respectively. Out of these strains, three strains of LAB and five strains of haloarchaea were found to be bacteriocin and halocin non-producer, respectively. The other strains demonstrated the presence of bacteriocins and halocins. The colorimetric assay was found to be rapid, specific and reliable for HTP screening of antimicrobial peptides such as bacteriocins and halocins from producer strains isolated from various natural resources.

Combination of 20% TCA peel with topical 5% ascorbic acid is a highly effective, safe and promising therapeutic option in treatment of melasma which significantly improves the QoL.