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Thin film Poly(piperazine-amide) composite membranes using sequential interfacial polymerization with tuning by Cu2+ have brought significant findings in it. The hydrophobicity is relatively enhanced for the copper containing membranes. The membrane in which copper solution is applied prior to piperizine (Memb-III) exhibits higher hydrophobicity where as membrane (Memb-II) in which copper solution is applied following piperizine, possesses higher roughness compared to other two. Filtration experiments in terms of salts, mono/disaccharides and hexaconazole indicate that modified membranes are of different behaviours according to their sequence of preparative methods. Memb-III has shown lower SO4=/Cl− selectivity compared to Memb-II (i.e. 3.92), though they are in different range. The unmodified membrane (Memb-I) exhibits SO4=/Cl− selectivity 3.23 is in the same scale of Memb-III (2.27). Memb-III exhibits higher hexaconazole separation (91.5%) compared to Memb-II (i.e. 53.9%). The flux decline follows the order: field water > tap water > deionized water. The copper incorporated membrane (Memb-II) has shown a low flux decline compared to Memb-III as well as Memb-I. The antibacterial properties towards E. Coli and Bacillus subtilis are well reflected. The copper containing membranes have promising antibacterial properties and follows the order Memb-II > Memb-III > Memb-I.

In this study, bacteria isolated from a lake were characterised for their chlorine resistivity and the effects of chlorination on growth, mortality, protein expression and attachment propensity towards membranes. Biofouling and membrane performance were analysed. All isolated chlorine resistant strains, characterised by 16s rRNA gene sequencing, belonged to the genus Bacillus. Chlorination caused limited effects on bacterial growth and mortality. B. safensis and B. lechinoformis suffered the maximum effects due to chlorination. Live-to-dead ratios immediately after chlorination were above 1.3, with some exceptions. The membrane pure water flux recovery was highly strain dependent. Irreversible membrane fouling was observed with B. aquimaris. Membrane flux decreased substantially during ultrafiltration of water containing chlorine resistant bacteria.

The biotransformation of 1,4-dioxane, a endrocrine disrupting chemical was achieved using different bacterial strains and their consortia. Three different bacterial isolates were screened on their ability to grow with 50 mg/L 1,4-dioxane in the basal mineral medium. Then the isolates were tested for its efficiency to biotransform 1000 mg/L 1,4-dioxane at varying period of time; 24–120 h. The isolates were distinguished by their morphological features and 16 S rRNA gene sequencing was done to evaluate the phylogenetic relationships. The isolates were identified as Bacillus marisflavi strain MGA, Aeromonas hydrophila strain AG and Shewanella putrefaciens strain AG. The degree of biotransformation was escalated by constructing a bacterial consortium using statistical tool; response-mixture matrix under the design of experiments. The fully grown bacterial strains were used as ingredients in different proportions to formulate the consortium. The biotransformation was analyzed for functional attenuation using spectroscopic techniques and reduction in 1,4-dioxane level was confirmed using mass spectrometry. The precise quantification of biotransformation using mass spectral profile revealed that the consortium removed 31%, 61% and 85% of 1000 mg/L 1,4-dioxane within 96, 120 and 144 h respectively. The activities of inducible laccase were elucidated during biotransformation of 1,4-dioxane. Bio-toxicity of treated and untreated 1,4-dioxane on brine shrimp; Artemia salina showed that the biotransformed products were less toxic. Therefore, this report would be first of its kind to report the biotransformation and detoxification of 1,4-dioxane by a statistically designed bacterial consortium.

This study intended to determine whether edible microalgae can play an active role as an anti-virulence agent for enteropathogens. It showed that Chlorella variabilis (ATCC PTA 12198) are able to inhibit the production of the virulence factors in pathogenic Vibrio cholerae strains, the causative agent of cholera cases. Total lipid extract from C. variabilis (TLCV) was able to suppress the cholera toxin (CT) production in multidrug-resistant variant V. cholerae strains without affecting their growth. Cell-cytotoxicity induced by cholera toxin was also arrested in the presence of TLCV. Further, in vivo study in the gut of Artemia salina showed slightly less colonization of V. cholerae in the presence of TLCV. GC-MS analysis of the TLCV revealed the presence of saturated and unsaturated fatty acids include 9-cis,12-cis-Linoleic acid (linoleic acid), 9,12 Octadecadienoic acid (linolenic acid), cis, cis, cis-6,9,12-Octadecatrienoic acid (γ-linolenic acid), cis-8,11,14-Eicosatrienoic acid (dihomo-gamma-linolenic acid) and cis-9-Octadecenoic acid (oleic acid). More specifically the aforesaid formulation works against most recent variant multidrug-resistant V. cholerae strain causing severe diarrhea. Thus, edible microalgae can a valuable natural source which possesses great potential to be developed as functional food ingredients and pharmaceutical products for reducing cholera.