Screening, nutritional optimization and purification for phytase produced by Enterobacter aerogenes and its role in enhancement of hydrocarbons degradation and biofilm inhibition.

In this study, a novel isolate of Enterobacter aerogenes isolated from contaminated soils with hydrocarbons had extracellular phytate-degrading activity. Enterobacter aerogenes isolates were identified by biochemical tests and confirmed by16S rRNA gene products (amplified size 211bp) for genotypic detection. The phytase activity was reached to maximum activity when this isolate was cultivated under the optimal conditions which consisted of using minimal salt medium containing 1%(w/v) rice bran as a sole source for carbon and 2% (w/v) yeast extract at pH 5.

Chitosan extracted from Aspergillus flavus shows synergistic effect, eases quorum sensing mediated virulence factors and biofilm against nosocomial pathogen Pseudomonas aeruginosa.

The biological methods for extraction of chitosan were used as alternative procedures for chemical methods In biological methods, the chitosan was extracted from A. flavus by using of Lactobacillus paracasei for demineralization and Bacillus subtilis for deproteinization. The yield of extracted chitosan reached to 53.