Prita B.,Swami Ramanand Teerth Marathwada University |
Chandrahas K.,Swami Ramanand Teerth Marathwada University |
Ramana P.V.,Osmania University |
Ragini B.,Swami Ramanand Teerth Marathwada University |
Swetha M.,Nsb College
Korean Journal of Chemical Engineering | Year: 2011
Lipase was extracted and purified from Pseudomonas aeruginosa SRT9. Culture conditions were optimized and highest lipase production amounting to 147.36 U/ml was obtained after 20 h incubation. The extracellular lipase was purified on Mono QHR5/5 column, resulting in a purification factor of 98-fold with specific activity of 12307.81 U/mg. Lipase was immobilized on tri (4-formyl phenoxy) cyanurate to form Schiff's base. An immobilization yield of 85% was obtained. The native and immobilized lipases were used for catalyzing the hydrolysis of olive oil in aqueous medium. Comparative study revealed that immobilized lipase exhibited a shift in optimal pH from 6.9 (free lipase) to 7.5 and shift in optimal temperature from 55 °C to 70 °C. The immobilized lipase showed 20-25% increase in thermal stability and retained 75% of its initial activity after 7 cycles. It showed good stability in organic solvents especially in 30% acetone and methanol. Enzyme activity was decreased by ~60% when incubated with 30% butanol. The kinetic studies revealed increase in KM value from 0.043 mM (native) to 0.10 mM for immobilized lipase. It showed decrease in the Vmax of immobilized enzyme (142.8 μmol min-1 mg-1), suggesting enzyme activity decrease in the course of covalent binding. The immobilized lipase retained its initial activity for more than 30 days when stored at 4 °C in Tris-HCl buffer pH 7.0 without any significant loss in enzyme activity. © 2010 Korean Institute of Chemical Engineers, Seoul, Korea.
Joshi S.R.,Shankarrao Chavan Mahavidyalaya |
Habib S.I.,Nsb College
Oriental Journal of Chemistry | Year: 2014
The Schiff bases have been synthesised by the reaction of Benzoinoxime primary ligand with heterocyclic compounds such as 2-aminothiazole (SL1) and 8-hydroxyquinoline (SL2) to form the secondary ligand, which than react with the metal halides to form complexes of Co (II) and Zn (II). The elemental analysis data shows that the metal to ligand ratio in all Co (II) simple is 1:2 for simple complexes and 1:2:2 for metal complex with oxime as a primary ligand and SL1as a secondary ligand while it is 1:2:1 for metal complex with oxime as a primary ligand and SL3 as a secondary ligand whereas Zn (II) complexes of mixed ligand exhibit the stoichiometry 1:2:2. The structural features have been determined from IR, UV-Vis, and XRD data. All the complex shows a distorted octahedral geometry to mononuclear Co (II) complexes of mixed ligands, while square planner geometry to mononuclear Co (II) complexes of oximes. Zn (II) complexes of mixed ligands shows a distorted octahedral geometry, while square planner geometry to mononuclear Zn (II) complexes of oximes. All the synthesised compounds were screened for antimicrobial activity.
Swetha M.,Nsb College |
Venkata Ramana P.,Osmania University |
Shirodkar S.G.,Nsb College
Asian Journal of Chemistry | Year: 2011
A new protocol for the synthesis of α,β-unsaturated esters was described with various aldehydes and ethyl acetate in presence of sodium hydride. Advantage of this method is high efficiency, shorter time period and inexpensive.