Lala Behari Sukla

Bioprospecting hot spring metagenome: lipase for the production of biodiesel

Screening of metagenomic library from Taptapani Hot Spring (Odisha) yielded a positive lipase clone (pUC-lip479). Sequence analysis showed an ORF (RK-lip479) of 416 amino acid residues which was overexpressed in Escherichia coli BL21 (DE3). Optimum pH and temperature of purified lipase RK-lip479 were 8.0 and 65xa0°C, respectively, and found to be stable over a pH range of 7.0–9.0 and temperatures 55–75xa0°C. RK-lip479 could hydrolyse a wide range of 4-nitrophenyl esters (4-nitrophenyoctanoate, 4-nitrophenyldodecanoate, 4-nitrophenylpalmitate, 4-nitrophenylmyristate and 4-nitrophenylstearate), and maximum activity was observed with 4-nitrophenyldodecanoate. RK-lip479 was resistant to many organic solvents, especially isopropanol, DMSO, methanol, DMF, ethanol, dichloromethane, acetone, glycerol and ethyl acetate. RK-lip479 also showed activity in the presence of monovalent (Na+ and K+), divalent (Mg2+, Mn2+, Ca2+, Hg2+, Cu2+, Co2+, Zn2+ and Ag2+ ) and trivalent cations (Fe3+ and Al3+). Yield of biodiesel production was in the range of 40–76% using various waste oils with RK-Lip479 under optimized conditions.

Statistical optimization for lipase production from solid waste of vegetable oil industry

ABSTRACT The production of biofuel using thermostable bacterial lipase from hot spring bacteria out of low-cost agricultural residue olive oil cake is reported in the present paper. Using a lipase enzyme from Bacillus licheniformis, a 66.5% yield of methyl esters was obtained. Optimum parameters were determined, with maximum production of lipase at a pH of 8.2, temperature 50.8°C, moisture content of 55.7%, and biosurfactant content of 1.693u2009mg. The contour plots and 3D surface responses depict the significant interaction of pH and moisture content with biosurfactant during lipase production. Chromatographic analysis of the lipase transesterification product was methyl esters, from kitchen waste oil under optimized conditions, generated methyl palmitate, methyl stearate, methyl oleate, and methyl linoleate.

Recent advances in indium metallurgy: A review

ABSTRACT The by-products of zinc refineries are used as the primary mineral resources for the commercial production of indium. The discarded LCDs containing adequate amount of indium is rather worth as its secondary resources compared to the by-products of zinc refineries. Mining and recycling rates of indium, respectively from minerals and waste LCDs are in progress to meet its huge demand. Recycling of the LCDs has been dominating over mining, as presently 480t of indium are produced annually from mining, however, that of 650t annually from recycling. Different aspects of the extractive metallurgy of indium are summarized in this review paper.

Studies on liquid-liquid extraction of yttrium and separation from other rare earth elements using bifunctional ionic liquids

ABSTRACT Solvent extraction of yttrium(III) from chloride and nitrate solutions were carried out using two bifunctional ionic liquids Cyphos IL 104 and [A336/Cy272]. Comparative study with their constituent extractants showed higher extraction abilities of the ionic liquids for Y(III). The extraction behavior of yttrium using the above ionic liquids was studied as function of different parameters. Ion association neutral complexes were formed in the organic phase. 0.5 M HNO3 could strip 82% and 75.6 % yttrium from the loaded organic phases of 0.01M [A336/Cy272] and Cyphos IL 104, respectively. Separation studies involving binary systems were also investigated.

Thin film of Yttria stabilised zirconia on NiO using vacuum cold spraying process for solid oxide fuel cell

Yttria stabilised zirconia (YSZ) was fabricated on a glass and NiO-YSZ anode support substrate using the vacuum cold spraying (VCS) technique at room temperature. The field emission scanning electrode microscope (FESEM) analysis revealed a dense microstructure and several vertical cracks within 0.1 μm width of the YSZ film. The transmission electron microscopy (TEM) was used to analyse the grain size and it was found to be 20 nm which was finer size compared to the average particle size of the starting YSZ powder. The x-ray diffraction (XRD) analysis showed lacking of phase transformation during the VCS process. The YSZ film fabricated by VCS technique showed better gas tightness compared to that fabricated by atmospheric plasma spray process. The Youngs modulus of the YSZ film was found to be 172 GPa.