Pre-screening of filamentous fungi isolated from a contaminated site in Southern Brazil for bioaugmentation purposes

Four Aspergillus sp. strains were isolated from contaminated soil in Rio Grande, Southern Brazil. The biodegradation potential of these strains was evaluated using a simple method involving the determination of colony growth rates on plates containing a specific hydrocarbon or petroleumderivative as the only carbon source. The LEBM1 strain presented a high tolerance level to BTX. It was the only strain capable of growth on all the media, with growth rates varying from 1.3 to 2.2 mm/day. The LEBM2 strain presented the potential for phenol degradation, while the LEBM3 strain could be used for gasoline, diesel oil, hexane and chlorobenzene

Evaluation of enzymatic extract with lipase activity of yarrowia lipolytica. an application of data mining for the food industry wastewater treatment

The object of this research was to obtain the Crude Enzymatic Extract (CEE) of Yarrowia lipolytica ATCC 9773, in the medium of 30% Water of Sales (SW) applying a biologically treatment to three different concentrations yeast inoculum food wastewater, collected from cheese and whey production. It was evaluated the behavior of the inoculum in a suitable medium that stimulates lipids biodegradation. The standard liquid-liquid partition method SM 5520 B was used to quantify fat and oil removal for each concentration of yeast, before treatment and post treatment. The Industrial Fat effluent was characterized by physical chemical patterns, and two treatments were evaluated; Treatment 1 consisted of pH 5.0 and treatment 2 with a pH of 6.5, both with the following characteristics; Concentration of inoculum 8% 12% and 16% at 27Â °C temperature and evaluation time 32Â h. The best results (2.702Â mg/L fat and 83% degradation oil) were found to be pH 5.0, 16% concentration and 27Â °C, BOD5, and COD decreased by 43.07% and 44.35%, respectively during the 32Â h; For pH 6.5, 8% concentration at 32Â h and at room temperature, degraded 2.177Â mg/L fat and oil (67% degradation); The BOD5, and COD decreased by 37.93% and 39.19%, in the same time span. The treatment at pH 5.0 inoculum concentration of 16% was effective in removing 83% of the volume of fats and oil in the effluent, representing a useful tool for the wastewater treatment

Production of 3,4-dihydroxy L-phenylalanine by a newly isolated Aspergillus niger and parameter significance analysis by Plackett-Burman design

<p>Abstract</p> <p>Background</p> <p>The amino acid derivative 3,4-dihydroxy L-phenylalanine (L-dopa) is gaining interest as a drug of choice for Parkinson's disease. <it>Aspergillus oryzae </it>is commonly used for L-dopa production; however, a slower growth rate and relatively lower tyrosinase activity of mycelia have led to an increasing interest in exploiting alternative fungal cultures. In the present investigation, we report on the microbiological transformation of L-tyrosine to L-dopa accomplished by a newly isolated filamentous fungus <it>Aspergillus niger</it>.</p> <p>Results</p> <p>The culture <it>A. niger </it>(isolate GCBT-8) was propagated in 500 ml Erlenmeyer flasks and the pre-grown mycelia (48 h old) were used in the reaction mixture as a source of enzyme tyrosinase. Grinded mycelia gave 1.26 fold higher L-dopa production compared to the intact at 6% glucose (pH 5.5). The rate of L-tyrosine consumption was improved from 0.198 to 0.281 mg/ml. Among the various nitrogen sources, 1.5% peptone, 1% yeast extract and 0.2% ammonium chloride were optimized. The maximal L-dopa was produced (0.365 mg/ml) at 0.3% potassium dihydrogen phosphate with L-tyrosine consumption of 0.403 mg/ml.</p> <p>Conclusion</p> <p>Over ~73% yield was achieved (degree of freedom 3) when the process parameters were identified using 2k-Plackett-Burman experimental design. The results are highly significant (p ≤ 0.05) and mark the commercial utility (LSD 0.016) of the mould culture which is perhaps the first ever report on L-dopa production from <it>A. niger</it>.</p

Parameters optimization for enzymatic assays using experimental design

The conditions for maximization enzymatic activity were determined using experimental design and inulinase from Kluyveromyces marxianus ATCC 16045. The effects of substrate concentration (sucrose and inulin), pH and temperature on inulinase activity were verified using four factorial design and surface response analysis. Using sucrose as substrate. It has bean shown that the effects sucrose on enzymatic activity is not statistically significant and the best condition for the highest activity (110 U/mL) was achieved with temperature between 60 degrees C and 68 degrees C and pH between 4.5 and 5.0. Using inulin as substrate it was verified that temperature is the only variable statistically significant and the maximum activity was 7.3 U/mL at temperature between 50 degrees C and 51 degrees C.23216317