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Chitosan is in prominence as membrane materials. The present study based on chitosan–tannic acid crosslinked moiety on polyacrylonitrile support membranes. FTIR-ATR, zeta potential, XRD, SEM, AFM, TGA, DSC and contact angle are used to understand the characters of the membranes. The separation performances of salts (NaCl, Na2SO4) proved that membranes are associated with charged nanofiltration separation behaviour. Memb-III has reached a maximum difference in salt separation performance (Na2SO4 90.88% and NaCl 35.76%) at ~ 134.4 Lm−2 h−1 compared to Memb-I and II. The membrane performances are marked with organic molecule markers (e.g. glucose and sucrose). The separation of molecular markers shows its direct relationship with its molecular size. The pH-dependent studies show that separation of riboflavin increases at pH 9 compared to separation at pH 7, whereas the reverse happens for flux. Memb-III shows a maximum 84.1% riboflavin separation having flux 55.82 Lm−2 h−1 at pH 9. The study with bacteria (viz. E. coli, Bacillus subtilis) also proves that the surface is antibacterial.

Environmental remediation with a single platform for selective sensing and removal of toxic analytes with recyclability of the material has always been a desirable system for sustainability. However, materials comprising all the abovementioned advantages are rarely known for oxoanions. We herein developed a fluorogenic napthalimide-based functionalized mesoporous silica material (SiO

Kappaphycus alvarezii seaweed extract (KSWE) is known to enhance crop productivity and impart stress tolerance and our preliminary studies showed their biostimulatory effect on soil bacteria also. Close to one quarter of the foliar spray carried out on maize falls on soil either as drift or from leaf as drip. Hence it was hypothesized, it would profoundly influence soil microbes under stress. An experiment was conducted with five treatments, with or without KSWE application at critical stages of maize under soil moisture stress and compared with an irrigated control. Illumina platform was employed for analysis of V3-V4 region of 16S rRNA gene from the soil metagenome. Total of 345,552 operational taxonomic units were generated which were classified into 55 phyla, 152 classes, 240 orders, 305 families and 593 genera. Shannon’s index and Shannon’s equitability indicated increased soil bacterial diversity by multiple KSWE applications under duress. The abundance of Steroidobacter, Balneimonas, Rubrobacter, Bacillus, Alicyclobacillus, Anaerolinea and Nitrospira genera decreased (49-79%) in drought imposed at V5,10, and 15 stages of maize over the irrigated control, while it significantly improved when followed by KSWE application under drought. Nitrosomonas, Nitrosovibrio, Rubrobacter, Flavobacterium genera and several other taxa which are important for plant growth promotion and nutrient cycling were found to be enriched by KSWE application under drought. Treatments having enriched microbial abundance due to KSWE application under stress recorded higher soil enzymatic activities and cob yield, suggesting the contribution of altered soil ecology mediated by KSWE as one of the reasons for yield improvement.

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.

Bacterial contaminated water causes potential health issues. Conventional chlorine treatment has shortcomings of environmental hazards and chlorine adoptability by the bacterial cells. Ultrafiltration membrane can intercept bacterial species from feed water. Membrane having anti-biofouling/antifouling properties is needed for the removal of bacteria from feed water. Herein, interpolymer membranes with inherent antimicrobial activity and fouling release property have been prepared by the blend of poly(vinylidene fluoride) (PVDF), poly(vinyl pyrrolidone) and partially long chain alkylated (C12 chain) poly(vinyl imidazole) copolymer (PVIm-co-PVIm-C12) followed by cross-linking of the remaining VIm groups with an activated di-halide compound. The membranes obtain with copolymers of degree of alkyl substitution (DS

The present investigation reports the biotransformation of an endrocrine disrupting agent; 1,4-dioxane through bacterial metabolism. Initially, potential bacterial isolates capable of surviving with minimum 1,4-dioxane were screened from industrial wastewater. Thereafter, screening was done to isolate a bacteria which can biotransform higher concentration (1000 mg/L) of 1,4-dioxane. Morphological and biochemical features were examined prior establishing their phylogenetic relationships and the bacterium was identified as Staphylococcus capitis strain AG. Biotransformation experiments were tailored using response surface tool and predictions were made to elucidate the opimal conditions. Critical factors influencing bio-transformation efficiency such as tetrahydrofuran, availability of 1,4-dioxane and inoculum size were varied at three different levels as per the central composite design for ameliorating 1,4-dioxane removal. Functional attenuation of 1,4-dioxane by S. capitis strain AG were understood using spectroscopic techniques were significant changes in the peak positions and chemical shifts were visualized. Mass spectral profile revealed that 1.5 (% v/v) S. capitis strain AG could completely (∼99%) remove 1000 mg/L 1,4-dioxane, when incubated with 2 μg/L tetrahydrofuran for 96 h. The toxicity of 1,4-dioxane and biotransformed products by S. capitis strain AG were tested on Artemia salina. The results of toxicity tests revealed that the metabolic products were less toxic as they exerted minimal mortality rate after 48 h exposure. Thus, this research would be the first to report the response prediction and precise tailoring of 1,4-dioxane biotransformation using S. captis strain AG.

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.

In the present study, we have demonstrated synthesis of agar aldehyde (Aald) from seaweed polysaccharide and its further successful application for preparation of Aald mediated solid silver nanocomposite (Aald-AgNPs). Aald-AgNPs were characterized for biophysical properties by FTIR, XRD, SEM, TEM, XPS, and UV-vis spectroscopy. Aald-AgNPs were further tested in vitro and in vivo for anticancer activity. The results of the in vitro study revealed that Aald-AgNPs exhibited activity against 3 cancer cell lines. Aald-AgNPs were found to act through causing dose dependent increase in cell size, inducing anueploidy, mitochondrial disintegration and increasing septa formation in cell cytoplasm. Results of in vivo anticancer activity against ME-180, Colon-26, and HL-60 xenograft mice tumor models showed 64 %, 27.3 % and 51 % reduction in tumor volume, respectively with 83-100 % survival rate. Aald-AgNPs exhibited excellent antibacterial activity. It was interesting to note that Aald-AgNPs did not exhibit any significant detrimental effect on viability and metabolic activity of normal bone marrow derived mesenchymal stem cells. This study opens new areas of research for chemists and biologists to use seaweed-derived polymers to develop nanocomposites for cancer therapeutics.

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.

2.5% w/w DNA (Salmon testes) was solubilized in a bio-deep eutectic solvent [(bio-DES), obtained by the complexation of choline chloride and ethylene glycol at 1:2 molar ratio] containing 1% w/w of silver chloride (AgCl) to yield a AgCl decorated DNA based hybrid material. Concentration dependent formation of AgCl crystals in the DES was observed and upon interaction with DNA it gave formation of a cephalopod shaped hybrid material. DNA was found to maintain its chemical and structural stability in the material. Further, AgCl microstructures were found to have orderly self assembled on the DNA helices indicating the electrostatic interaction between Ag(+) and phosphate side chain of DNA as a driving force for the formation of the material with ordered microstructural distribution of AgCl. Furthermore, the functionalized material exhibited excellent antibacterial and bactericidal activity against both Gram negative and Gram positive pathogenic bacteria.