Original Research Article

OPTIMIZATION OF CULTURAL PARAMETERS OF Aspergillus costaricaensis CBS115574 FOR LIPASE PRODUCTION BY SOLID-STATE FERMENTATION

PRIYA CHAUDHARY, ARUN KUMAR SHARMA, PRACHETA .

Asian Journal of Microbiology and Biotechnology, Volume 4, Issue 3, Page 108-118

In the present study, Aspergillus costaricaensis CBS115574 which was previously isolated from the non-leguminous field soil collected from the Kishangarh city of state Rajasthan confirmed by 16S rRNA gene/ITS/D1-D2 region sequencing. The cultural parameters (Carbon sources, nitrogen sources, moisture content, pH, temperature and particle size etc) of solid-state fermentation have been optimized for the improved extracellular lipase production. Among different carbon sources, A. costaricaensis showed best lipase activity (253.6 IU/g/min) in the presence of lactose. Among the various concentration (0.2%, 0.4%, 0.6%, 0.8%, 1.0%, 1.2%, 1.4% and 1.6%) of lactose, the optimum concentration was found to be 1.6%. Among different nitrogen sources, highest lipase activity (55.32 IU/g/min) was obtained in the presence of yeast extract and the optimum concentration of yeast extract was found to be 0.5% for maximum lipase activity (236.69 IU/g). Further the best lipase activity was obtained in the medium of pH 8.0 (312.330 IU/g/min) at 28ºC after 48 hrs of incubation period. Further the particle size of solid substrate was optimized and highest lipase activity was found when fine particle size was used. Among the various ratio of moisture content, highest lipase activity (317.09 IU/g/min) was found at 1:6 moisture content. From the present work, it is figure out that for the enhanced production of lipases the medium parameters required to be optimized. The above results help out the authors in carry out the further studies of purification and characterization of lipase enzyme produced from A. costaricaensis CBS115574.

Original Research Article

PURIFICATION AND CHARACTERIZATION OF EXTRACELLULAR LIPASE ENZYME FROM Aspergillus costaricaensis CBS115574

PRIYA CHAUDHARY, ARUN KUMAR SHARMA, PRACHETA .

Asian Journal of Microbiology and Biotechnology, Volume 4, Issue 3, Page 119-134

In the present study, the lipase of alkaline nature obtained from the previously isolated strain Aspergillus costaricaensis CBS115574 was characterized and purified out using ammonium sulfate precipitation and chromatographic techniques on Diethylaminoethyl A-50 and Sephadex G-100. The purified lipase has the molecular weight of ~50 kDa which was determined by Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Zymography by using the phenol red along with the purification fold of 6.63 and specific activity of 31.73 IU/mg after the gel filtration chromatography. Lipase was found to be stabilized at the pH 7 (122.68 IU/g/min) and at the temperature of 80ºC (141.36 IU/g/min) with its optimal activity at pH 8 and temperature 50ºC. The Km and Vmax value for extracellular lipase were reported to be 29.62 mM and 74.07 IU/ml with their higher tolerance to glycerol (organic solvent), tween 80 (detergent), Ethylene diamine tetra acetic acid (activator & inhibitor), hydrogen peroxide (oxidizing & reducing agent) and sodium chloride (metal ions) with lipase activity of 106.74 IU/g/min, 84.53 IU/g/min, 108.06 IU/g/min, 97.17 IU/g/min and 118.7 IU/g/min. The above results suggested that A. costaricaensis CBS115574 lipase found a suitable position for application in different types of industries.

Original Research Article

POLYHYRDOXYBUTYRATE PRODUCTION BY Bacillus marcorestinctum USING A CHEAPER SUBSTRATE AND ITS ELECTROSPINNED BLENDS WITH POLYMER

SWETHA NARAYANKUMAR, NEETHU K. SHAJI, VEENA GAYATHRI KRISHNASWAMY

Asian Journal of Microbiology and Biotechnology, Volume 4, Issue 3, Page 149-160

Poly(hydroxybutyric acid) (PHB) and other biodegradable polyesters are promising candidates for the development of environment-friendly and completely biodegradable plastics. One of the major drawbacks in the production of PHB is production costs, since it requires large amount of carbon source. This calls for cheaper substrates that can be used as an alternative carbon source such as agro-industrial residues. Hence in the present work PHB producing bacterial strain was used to study the effect of different cheaper carbon and nitrogen sources in the production of PHB from batch work to a scale up level. The large scale production of PHB produced was further characterized by, FT-IR, NMR, GC-MS and TEM analysis. In this study, cane molasses was used as an additional carbon source at 2% concentration along with glucose for large scale production of PHB. Ammonium nitrate was used as the nitrogen source and the C:N ratio was maintained at 1:15. The maximum production of PHB was obtained at 24 hours of growth which was found to be 0.5 g/L and had a dry cell weight of 3.7 g/ L. The PHB produced was further analysed by GC-MS Analysis and Transmission Electron Microscopy (TEM). The obtained PHB from scale-up studies were further electros pinned using different blends of polymers.

Review Article

POTENTIAL MICROBIAL APPLICATIONS OF METAL COMPLEXES CONTAINING AMINO ACID DERIVED SCHIFF BASE LIGANDS: AN OVERVIEW

MD. SADDAM HOSSAIN, MD. NUR AMIN BITU, MD. MAHASIN ALI, MD. FARUK HOSSEN, MD. ALI ASRAF, MD. ABDUL MANNAN, MD. KUDRAT-E-ZAHAN

Asian Journal of Microbiology and Biotechnology, Volume 4, Issue 3, Page 135-148

Antibiotic resistance has dropped dramatically day by day at an alarming rate. In this view there is a strong need to prepare new compounds that not only have potential activity, but having new appliances of action. Inorganic compounds particularly metal complexes have played a significant role in the improvement of potential metal based drugs. The aim of this review is to focus on research undertaken over the past few decades which has sought to possess preclinical pharmacological screenings like anti-bacterial, anti-fungal, anti-tuberculosis, anti-inflammatory, anti-cancer, DNA- interaction and anti-tumor activity of metal complexes containing Schiff base ligands derived from amino acids.