Statistical Optimization for Coproduction of Chitinase and Beta 1, 4-Endoglucanase by Chitinolytic Paenibacillus elgii PB1 Having Antifungal Activity.

A bacterial strain PB1 with antagonistic activity against pathogenic fungi was isolated from marine soil and was identified as Paenibacillus elgii based on phenotypic and genotypic characterization. The isolate showed good antifungal activity against "Aspergillus niger (MTCC 282), Trichophyton rubrum (MTCC 791), Microsporum gypseum (MTCC 2819), Candida albicans (MTCC 227), and Saccharomyces cerevisiae (MTCC 170)". Chitinase and beta 1, 4-endoglucanase are known for their capability to degrade fungal cell wall, thus we analyzed its productivity in PB1 strain using Plackett-Burman and Central Composite Design. The factors that affect the productivity of chitinase and beta 1, 4-endoglucanase were identified and optimized. A 7.77-fold increase (3.157 to 24.53 ± 1.33 U/mL) in chitinase and 7.422-fold increase (6.476 to 48.066 ± 0.676 U/mL) in beta 1, 4-endoglucanase versus basal medium was achieved. Chitinase and beta 1, 4-endoglucanase produced by Paenibacillus elgii strain PB1 represents the new source for biotechnological, medical, and agricultural applications.

Production of ß -cyclodextrin from pH and thermo stable Cyclodextrin Glycosyl Transferase, obtained from Arthrobacter mysorens and its evaluation as a drug carrier for Irbesartan.

Cyclodextrins (CDs) are carrier molecules produced by cyclization of α-1,4-glucans by Cyclodextrin Glycosyl Transferase (CGTase). These torus shaped molecules have hydrophobic cavity and hydrophilic shell making them useful in pharmaceutical, food, textile, pesticide and cosmetic industries. In this study, culture conditions for the production of CGTase by organism belonging to Arthrobacter genus obtained from a paddy field soil were optimized by single parameter mode. Soluble starch, yeast extract and magnesium sulphate played an important role in CGTase production. Percentage increase in CGTase yield under optimized conditions was 396.77%. The enzyme precipitated by 60% ammonium sulphate was purified using DEAE-sepharose. The molecular weight of the purified protein as determined by SDS-PAGE was 75 kDa. Purified CGTase was thermostable and stable over a wide pH range. Dissolution studies on ß -cyclodextrin-Irbesartan complex revealed that ß -CDs formed were useful in preparing immediate release oral dosage forms.

A Fractional Factorial Design to Study the Effect of Process Variables on the Preparation of Hyaluronidase Loaded PLGA Nanoparticles.

The present study was initiated to understand the effect of PLGA concentration, PVA concentration, internal-external phase ratio, homogenization speed, and homogenization time on mean particle size, zeta potential, and percentage drug encapsulation using fractional factorial design. Using PLGA (50-50) as the carrier, hyaluronidase loaded PLGA nanoparticles were prepared using double emulsion solvent evaporation technique. The particle size was analyzed by dynamic light scattering technique and protein content by Lowry method. The study showed that homogenization speed as an independent variable had maximum effect on particle size and zeta potential. Internal-external phase volume ratio had maximum effect on drug encapsulation. Mean particle size also had high dependency on the combined effect of PVA concentration and phase volume ratio. Using fractional factorial design particle size of <400 nm, zeta potential of <-30 mV, and percentage encapsulation of 15-18% were achieved.

Optimization of cultural conditions for protease production by a fungal species.

Studies were carried out on a paddy soil fungal isolate identified to be a strain of Aspergillus niger from Manipal. The parameters that largely impact enzyme production viz., fermentation time, impeller speed, pH, temperature and nutrient supplements were studied. Optimization of production parameters for production of protease was done by the single-parameter mode. Casein served as substrate and proteolytic activity was estimated using Folin-Ciocalteau method at 660 nm. A maximum yield of 71.3 mg tyrosine/g casein substrate was produced in 96 h on a soluble starch medium at pH 4 in shake flask experiments. Production was carried out on a 3-liter fermenter and 40.7 mg of tyrosine was liberated/g of substrate. The enzyme was extracted with 50% ammonium sulfate and sodium dodecyl sulfate-Polyacrylamide gel electrophoresis showed two bands having mw 45.7 kDa and 38.5 kDa, respectively. The enzyme activity was found to be 147.84 U/ml.

Synergy of gatifloxacin with cefoperazone and cefoperazone-sulbactam against resistant strains of Pseudomonas aeruginosa.

Chequerboard and time-kill methods were used to compare the in vitro efficacies of the combinations gatifloxacin (GAT) with cefoperazone (CFP) and GAT with cefoperazone-sulbactam (CFP-SUL) against 58 clinical isolates of Pseudomonas aeruginosa. The combinations GAT+CFP and GAT+CFP-SUL were shown to be synergistic for 36.2 and 58.6 % of isolates tested, respectively, using the chequerboard method. Time-kill studies with 11 strains showed synergy in 54.5 % for the GAT+CFP combination and 72.7 % for the GAT+CFP-SUL combination. The agreement between these two methods was found to be 72-81 %. There was a significant difference in synergy between the two combinations tested (P=0.011).