Cost Effective Production of Poly-β-Hydroxybutyrate by Bacillus subtilis NG05 Using Sugar Industry Waste Water

The present study describes the treatment of sugar industry waste water and its use as a potential low cost substrate for production of bioplastic by Bacillus subtilis NG05. The B. subtilis NG05 grow at the rate of 0.14 g h^?1 L^?1 of production media used and accumulate the 50.1 % of poly β-hydroxybutyrate (PHB). The phase contrast microscopy revealed the presence of PHB granules in B. subtilis NG05 which was further confirmed by Fourier transform infrared spectroscopy and ¹H-nuclear magnetic resonance. The polymer was further analysed by differential scanning calorimetry. PHB production yield was achieved up to 4.991 g L^?1 with Sugar industry waste water as sole nutrient source. Thus the process provided dual benefits of conversion of a waste material into value added product, PHB and waste management.     

Adsorption of malachite green and chrysoidine-Y by Sn-pillared clay

The aim of this research was to pillar the bentonite clay (Bt) with polyhydroxy tin chloride. The synthesized Tin-pillared interlayer clay (Sn-PILC) was characterized using X-ray diffraction (XRD), Fourier Transform Infrared spectra (FT-IR), Brunauer-Emmer Teller (BET) analysis, Thermogravimetric analysis (TGA), and Scanning Electron Microscopy (SEM). Adsorption capacity of raw-Bt and tin pillared interlayer clay (Sn-PILC) was examined for two dyes, namely, Malachite Green (MG) and Chrysoidine-Y (CY) from their aqueous solutions. The effects of physicochemical parameters like solution pH, dose, and dye concentration were investigated. The maximum adsorption efficiency at equilibrium dye concentration for Sn-PILC was 66.229 mg g^–1 for MG and 63.792 mg g^–1 for CY. Sn-PILC obeyed Langmuir isotherm for both the dyes whereas raw-Bt followed Freundlich isotherm. On the other hand, both adsorbents followed PFO as well as PSO kinetic model, indicating physisorption assisted by chemisorption. Thermodynamic studies were performed to determine the adsorption behavior of Sn-PILC for both the dyes. Regeneration studies revealed 80% efficiency up-to five adsorption-desorption cycles.     

Comparative study of leaching of silver nanoparticles from fabric and effective effluent treatment

Nano silver (Ag_n) is employed as an active antimicrobial agent, but the environmental impact of Ag_n released from commercial products is unknown. The quantity of nanomaterial released from consumer products during use should be determined to assess the environmental risks of advancement of nanotechnology. This work investigated the amount of silver released from three different types of fabric into water during washing. Three different types of fabric were loaded with chemically synthesized Ag nanoparticles and washed repeatedly under simulated washing conditions. Variable leaching rates among fabric types suggest that the manufacturing process may control the release of silver reaching the waste water treatment plants. In an attempt to recover the Ag_n for reutilization and to save it from polluting water, the effluents from the wash were efficiently treated with bacterial strains. This treatment was based on biosorption and was very efficient for the elimination of silver nanoparticles in the wash water. The process ensured the recovery of the Ag_n leached into the effluent for reutilization, thus preventing environmental repercussions.     

Studies on mycorrhizal inoculation on dry matter yield and root colonization of some medicinal plants grown in stress and forest soils

Five medicinal plants viz. Abelmoschatus moschatus Linn., Clitoria tematea L., Plumbagozeylanica L., Psorolea corylifolia L. and Withania sominifera L. were grown in a polypot experiment in five soils representing coal mine soil, coppermine soil, fly ash, skeletal soil and forest soil with and without mycorrhizal inoculations in a completely randomized block design. Dry matter yield and mycorrhizal root colonization of plants varied both in uninoculated and inoculated conditions. The forest soil rendered highest dry matter due to higher yield of A. moschatus, P. zeylanica and P corylifolia while fly ash showed lowest dry matter without any inoculants. P. cematea were best in coalmine soil and W. sominifera in copper mine soil without mycorrhizal inoculation. The mycorrhiza was found to enhance the dry matter yield. This contributed minimum 0.19% to maximum up to 422.0% in different soils as compared to uninoculated plants. The mycorrhizal dependency was noticed maximum in plants grown in fly ash followed by coal mine soil, copper mine soil, skeletal soil and forest soil. The mycorrhizal response was increased maximum in W. sominifera due to survival in fly ash after inoculation followed by P corylifolia and P cematea. Percent root colonization in inoculated plant was increased minimum of 1.10 fold to maximum of 12.0 folds in comparison to un-inoculated plants . The native mycorrhiza fungi were also observed to colonize 4.0 to 32.0% roots in plants understudy. This study suggests that mycorrhizal inoculation increased the dry matter yield of medicinal plants in all soils under study. It also helps in survival of W. sominifera in fly ash.     

Mercury induced architectural alterations in the gill surface of a fresh water fish,Channa punctatus

An air-breathing fresh waterfish Channa punctatus was exposed chronically to sublethal concentrations of mercuric chloride and the respiratory surface was found to exhibit lesions, lifting of lamellar epithelium and increased number of mucus gland openings. The damage increased with increase in the concentrations. The gill surface was studied using scanning electron microscope.