Dyeing effluents have become a vital source of water pollution. Due to the xenobiotic properties and toxicity to all life forms including humans, removal of undesirable color and associated toxicity is crucial. In this study, five dye decolorizing bacteria were isolated from dyeing effluent using selective enrichment culture in Bushnell-Haas (BH) medium amended with co-substrate (i.e. glucose, yeast extract) and 100 mg L−1 of each commercially available reactive dyes viz. Novacron Orange FN-R, Novacron Brilliant Blue FN-R, Novacron Super Black G, Bezema Yellow S8-G and Bezema Red S2-B. The isolated bacteria were identified and assigned as Neisseria sp., Vibrio sp., Bacillus sp., Bacillus sp. and Aeromonas sp. based on their phenotypic (cultural, morphological, physiological and biochemical characteristic) observation. The dye decolorization efficiency was estimated spectrophotometrically up to 6 days of static incubation at 37 °C and observed that all of the isolates were unable to induce decolorization in absence of co-substrate. In case of monoculture, decolorization percentage varies from no visible decolorization (Bezema Red S2-B by Ek-5) to highest 90% decolorization (Novacron Brilliant Blue FN-R by Ek-13) whereas the decolorization percentage of bacterial consortium varies from 65% (Bezema Yellow S8-G) to 90% (Novacron Brilliant Blue FN-R and Novacron Super Black G). The study outlines the co-substrates mediated decolorization process where bacterial consortium proved as efficient dye decolorizer than that of the monocultures. This finding confers possibility of using novel microbial consortium for biological treatment of disreputable dyeing effluents.

Pectinase is one of the important enzymes of industrial sectors. Presently, most of the pectinases are of plant origin but there are only a few reports on bacterial pectinases. The aim of the present study was to isolate a novel and potential pectinase producing bacterium as well as optimization of its various parameters for maximum enzyme production. A total of forty bacterial isolates were isolated from vegetable dump waste soil using standard plate count methods. Primary screening was done by hydrolysis of pectin. Pectinase activity was determined by measuring the increase in reducing sugar formed by the enzymatic hydrolysis of pectin. Among the bacterial isolates, the isolate K6 exhibited higher pectinase activity in broth medium and was selected for further studies. The selected bacterial isolate K6 was identified as Chryseobacterium indologenes strain SD. The isolate was found to produce maximum pectinase at 37°C with pH 7.5 upon incubation for 72 hours, while cultured in production medium containing citrus pectin and yeast extract as C and N sources, respectively. During enzyme-substrate reaction phase, the enzyme exhibited its best activity at pH of 8.0 and temperature of 40°C using citrus pectin as substrate. The pectinase of the isolate showed potentiality on different types of fruit juice clarification.

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Bisbicyclo[1.1.1]pentyldiazene, the smallest bicyclic azo compound, has been synthesized from the precursor [1.1.1]propellane via synthesis of N,N'-bis(bicyclo[1.1.1]pentyl)sulfamide and azoxybicyclo[1.1.1]pentane. The UV absorption of this diazene at 382 nm indicates that the compound is the trans isomer. Conversion to the cis isomer by irradiation was not possible because of attainment of a photostationary state. However, on the basis of the photochemical studies, the absorption of the cis-[1.1.1] isomer is estimated to be 384 nm.

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