ZnO nanoparticles of different sizes were functionalized with an amphipathic peptide, and its effect on nanoparticle stabilization and UV photoprotective activity was studied in this article. The peptide-modified nanoparticles exhibited lower aggregation, significant reduction in Zn 2+ leaching in vitro and even inside the cells for smaller particle sizes, reduced photocatalytic activity, and reduced cellular toxicity under UV-B treated conditions. In addition, the peptide-modified 60 nm ZnO nanoparticles showed lower genotoxicity, lower oxidative stress induction levels, less DNA damage responses, and less immunogenic potential than the bare counterparts in the presence of UV-B rays. They localized more in the stratum corneum and epidermis ex vivo, indicating better retention in epidermis, and demonstrated improved UV-B protection and/or skin integrity in SKH-1 mice in vivo compared to unmodified nanoparticles and commercial UVprotective agents tested. To our knowledge, this is the first report on the application of peptide-modified ZnO nanoparticles for improved photoprotection.

Recent literature has suggested a novel symbiotic relationship between bacteriophage and metazoan host that provides antimicrobial defense protecting mucosal surface by binding to host matrix mucin glycoproteins. Here, we isolated and studied different bacteriophages that specifically interact with human extracellular matrix molecules such as fibronectin, gelatin, heparin and demonstrated their potency for protection to host against microbial infections. We showed that subpopulations of bacteriophages that work against clinical isolates of Escherichia coli can bind to pure gelatin, fibronectin and heparin and reduced bacterial load in human colon cell line HT29. The bacteriophages were characterized with respect to their genome sizes, melting curve patterns and host tropism (cross-reactivity with different hosts). Since, the bacteriophages are non-toxic to the host and can effectively reduce bacterial load in HT29 cell line their therapeutic potency against bacterial infection could be explored.

We report the draft genome sequence of a putative probiotic strain, Lactobacillus fermentum ASBT-2, isolated from domestic sewage in Kerala, India. The strain showed probiotic properties (tolerance to low pH and bile salts, binding to host matrix) and reduced the coliform count by 90% in a biofilter used to treat wastewater.

Enteric infection by faecal contamination of drinking water is a major concern in developing nations contributing to the huge burden of malnutrition and infant mortality. We have developed a holistic approach, named as gut to gutter approach, to treat wastewater treatment, by screening potential probiotic strains from staple food sources. The strains could be potentially used for competing out the enteric pathogens in different applications such as food and wastewater treatment. We focused on two strains isolated from rice water (RS) and lemon pickle (T1), identified as Lactobacillus fermentum and characterized for their probiotic and wastewater treatment capabilities. The strains showed many probiotic properties (tolerance to low pH (pH 3), bile salts up to 0.5% and simulated gastric juice at low pH and binding to extracellular matrix molecules, heparin and gelatin. Auto-aggregation of T1 was in the range of 85% and the strain exhibited significant co-aggregating ability with enteric pathogens, Klebsiella pneumoniae, Salmonella enterica and E. coli (MDR) with 48%, 79% and 65% respectively. Both strains had a higher binding affinity to gelatin and heparin, compared to widely claimed “probiotic” Bacillus clausii and the pathogenic E. coli ET. The strains had high galactosidase activities. Further, the cell free supernatant from RS showed BLIS (bacteriocin like inhibitory substance) activity against Klebsiella pneumoniae, Staphylococcus aureus and Salmonella enterica at 60%, 48% and 30% respectively. T1 strains and B. clausii effectively reduced the coliform count by by 90% (1-log) when immobilized in a biofilter to treat wastewater.

Background: Chitin is the main component of fungal, protozoan and helminth cell wall. They help to maintain the structural and functional characteristics of these organisms. The chitin wall is dynamic and is repaired, rearranged and synthesized as the cells develop. Active synthesis can be noticed during cytokinesis, laying of primary septum, maintenance of lateral cell wall integrity and hyphal tip growth. Chitin synthesis involves coordinated action of two enzymes namely, chitin synthase (that lays new cell wall) and chitinase (that removes the older ones). Since chitin synthase is conserved in different eukaryotic microorganisms that can be a ‘soft target’ for inhibition with small molecules. When chitin synthase is inhibited, it leads to the loss of viability of cells owing to the self- disruption of the cell wall by existing chitinase. Methods: In the described study, small molecules from plant sources were screened for their ability to interfere with hyphal tip growth, by employing Hyphal Tip Burst assay (HTB). Aspergillus niger was used as the model organism. The specific role of these small molecules in interfering with chitin synthesis was established with an in-vitro method. The enzyme required was isolated from Aspergillus niger and its activity was deduced through a novel method involving non-radioactively labelled substrate. The activity of the potential lead molecules were also checked against Candida albicans and Caenorhabditis elegans. The latter was adopted as a surrogate for the pathogenic helminths as it shares similarity with regard to cell wall structure and biochemistry. Moreover, it is widely studied and the methodologies are well established. Results: Out of the 11 compounds and extracts screened, 8 were found to be prospective. They were also found to be effective against Candida albicans and Caenorhabditis elegans. Conclusion: Purified Methyl Ethyl Ketone (MEK) Fraction1 (F1) of Coconut (Cocos nucifera) Shell Extract (COSE) was found to be more effective against Candida albicans with an IC50 value of 3.04 μg/mL and on L4 stage of Caenorhabditis elegans with an IC50 of 77.8 μg/mL.