Biotechnological application of bacterial alkaline thermostable enzymes in bio-detergent industry

This is an investigation concerned on the production of alkaline thermostable microbial enzymes for application in biodetergent technology. Bacillus licheniformis- B42 and Geobacillus stearothermophilus -B78 were selected and identified among one hundred and fifty-three thermophilic bacterial isolates with respect to their ability to produce alpha-amylases, cellulases, proteases and lipases grown on some agro-industrial wastes at 55 degree C and at pH 9 for application in biodetergent technology. Productivity of four alkaline thermostable enzymes by both selected strains using slaughter house wastes [SHW] as best substrate for proteases and lipases and potato peel [PP] as best substrate for alpha-amylases and cellulases. The enzymatic level more affected by incubation temperature, pH, SHW and PP concentrations, inoculum size, incubation period, carbon, nitrogen, metal inducer and vitamins sources, under shaking conditions. Four alkaline thermostable enzymes were produced under all optimal nutritional and environmental conditions and purification by column chromatography on Sephadex G200 and G100, respectively were performed. Purification of four produced alkaline thermostable enzymes steps resulted in raising the purification fold to 17.04,15.24, 411.9 and 27.33 times in comparable with crude enzymes for alpha-amylase. cellulase, protease and lipase, respectively. The wash performing analysis of the four enzymes revealed that, it could effectively remove a variety of stains such as blood, apple, chocolate, mango, strawberry, salad and pomegranate by treatment at 55 degree C for 15 min when alkaliphilic-thermostable crude/purified enzymes were added separately or in combination with or without detergent [Rabso] as an Egyptian local detergent product. The crude enzymes of these two bacterial strains proved to be potentially candidates for the application in the detergent technology

Selection and characterization of bacteria esolated from petroleum refining effluents with polycyclic aromatic hydrocarbons [PAHS] removal capacities and its conditions

In this study, we evaluated the effect of different nutritional and environmental conditions on the percentages removal of PAHs present in petroleum refining effluent samples from the corrugated plate interceptor [API] of Cairo Oil Refining Co. [CORC], Egypt Two hundred twelve and two hundred forty two bacterial strains were isolated from six petroleum refinery oil polluted effluents samples collected from CORC in summer and winter seasons, respectively which were selected due to their growing capacity in the presence of oil as sole carbon source. From these strains four bacterial strains were further selected on the basis of their relatively good growing on hydrocarbon utilizing media, culture characteristics and capacity to biodegrade PAHs. These bacterial isolates were identified on the basis of cell shape, cell arrangement, relation to oxygen and nutritional and biochemical characteristics. The four bacterial strains were found to belong to Pseudomonas oleovorans-W7DAFO22, Enterobacter cloacae-S7DAF122, Pseudomonas stutzeri-S8API12 and Enterobacter aerogenes-W5OA31.They were capable to grow on the mineral salts media amended with crude oil as sole carbon source. Our results show that these strains can remove the PAHs by different percentages [%] at different pH values [4-9], NaCl concentrations [1-10%] and different nitrogenous and phosphorous sources. In conclusion, current sequence information provides the basis for a robust tool to estimate the PAHs degradation potential of different petroleum hydrocarbon contaminated sites undergoing in situ bioremediation