Enhanced production of Aspergillus tamarii lipase for recovery of fat from tannery fleshings

The influence of various oil cakes has been investigated for high level production of lipase using Aspergillus tamarii MTCC 5152. By solid state fermentation in wheat bran containing 2.5% w/w gingili oil cake at 70% v/w moisture content the fungus produced a maximal yield of lipase (758 ± 3.61 u/g) after 5 days of incubation using 2% v/w inoculum containing 10(6) spores/mL. Wheat bran and gingili oil cake with supplementation of gingili oil (1.0% w/w), glucose (0.5% w/w) and peptone (0.5% w/w) gives an increased enzyme production of 793 ± 6.56 u/g. The enzyme shows maximum activity at pH 7.0, temperature 50 °C and was stable between the pH 5.0-8.0 and temperature up to 60 °C. Crude lipase (3%) applied to tannery fleshing shows 92% fat solubility. The results demonstrate that fat obtained from tannery fleshing, a by-product of the leather industry has a high potential for biodiesel production and the proteinaceous residue obtained can be used as animal feed.

Enhanced production of Aspergillus tamarii lipase for recovery of fat from tannery fleshings.

The influence of various oil cakes has been investigated for high level production of lipase using Aspergillus tamarii MTCC 5152. By solid state fermentation in wheat bran containing 2.5% w/w gingili oil cake at 70% v/w moisture content the fungus produced a maximal yield of lipase (758 ± 3.61 u/g) after 5 days of incubation using 2% v/w inoculum containing 10(6) spores/mL. Wheat bran and gingili oil cake with supplementation of gingili oil (1.0% w/w), glucose (0.5% w/w) and peptone (0.5% w/w) gives an increased enzyme production of 793 ± 6.56 u/g. The enzyme shows maximum activity at pH 7.0, temperature 50 °C and was stable between the pH 5.0-8.0 and temperature up to 60 °C. Crude lipase (3%) applied to tannery fleshing shows 92% fat solubility. The results demonstrate that fat obtained from tannery fleshing, a by-product of the leather industry has a high potential for biodiesel production and the proteinaceous residue obtained can be used as animal feed.

Microbial biosurfactants and hydrolytic enzymes mediates in situ development of stable supra-molecular assemblies in fatty acids released from triglycerides.

The present study demonstrates in situ formation of multilamellar stable vesicles (MLSVs) of fatty acids released during the growth of microorganisms in the presence of triglycerides. Release of lipase during initial phase of growth hydrolyzes the triglycerides and release free fatty acids (mono or diglycerides) and glycerol. By extending the growth and the prevailing composition of media (unspent nutrients, salts, pH of the medium, biosurfactants, fatty acids, glycerol) and agitation transforms free fatty acids to MLSV of both cylindrical and spherical macroscopic structures via micelle formation with in 240h of incubation. Cross-sectional view and SEM analysis of macroscopic structures reveal the existence of continuous multilayering. Thermo-gravimetric analysis illustrates the stability of the vesicles. FT-IR analysis emphasizes the presence of amide linkages, responsible for self-assembly processes. Schematic representation of formation of MLSV demonstrated for further understanding. Additional exploration on MLSV formation in arteries and the relationship between MLSV and in situ plaque formation by the components of blood in the arteries are schematically explained and submitted as supporting information (SI-2).

Antimicrobial activity of secondary metabolite from marine isolate, Pseudomonas sp. against Gram positive and negative bacteria including MRSA.

A proteobacterium isolated from coastal region of Chennai, India, produced appreciable secondary metabolite and partial purification of the obtained secondary metabolite demonstrated antimicrobial activity against both Gram positive and negative organisms including MRSA (methicillin resistant Staphylococcus aureus). Identification of the isolate using biochemical tests, 16s rDNA sequence analysis, G+C content and electron microscopy studies revealed, isolate belonged to Pseudomonas genera. Extraction, purification, characterization and antimicrobial activity of secondary metabolite carried out using various standard instrumental techniques suggested that the active fraction was of 272 m/z with a stable fragment of 244 m/z and also displayed stable free radical activity assessed using EPR analysis. This stable free radical activity of secondary metabolite mediated its antimicrobial activity.

Vesicle formation in hydrocarbons assisted with microbial hydrolases and biosurfactants.

The present study demonstrates the role of microbial hydrolases in the transformation of hydrocarbons (soybean, sunflower, groundnut and gingelly oil, etc.) to vesicles. The combined effect of lipolytic enzyme generation and biosurfactants production during microbial growth at optimized media and environmental conditions mediates this transformation. Among the microbial species, Candida albicans exhibit complete transformation compared to Pseudomonads and Bacillus sps. Within hydrocarbons, only soybean and sunflower oils transformed to solid mass and no change with the remaining oils. Characterization of the vesicles revealed an increase in total weight by 160-180% compared to the original weight of hydrocarbon taken for the study and more than 73% increases in viscosity. Acid value and saponification value also showed an increase, respectively, by 78 and 84%. The bound water content estimated was 26%. Light microscopic analysis exhibit, presence of unilamellar and bi-lamellar structures.