ABSTRACT
The present investigation, focused on screening of various fungal species for Lovastatin production using different agro-based wastes, also, for maximizing lovastatin productivity by isolated Aspergillus fumigatus using response surface methodology (RSM). The following substrates (Olive cake; Pea pods; sugarcane bagasse; wheat bran; rice hulls; beet peel; Potato peel and groundnut shells) were screened to evaluate their effectiveness for lovastatin production, using different fungal species, (Aspergillus niger; Rhizopus oligosporus; Penicillium citrinum and isolated Aspergillus fumigatus) under solid state fermentation (SSF). Wheat bran was the most suitable substrate for lovastatin production with all fungal species. Optimum conditions of lovastatin production by wheat bran have been attained efficiently by response surface methodology (RSM) using isolated Aspergillus fumigatus under solid state fermentation (SSF). The lovastatin yield of (3.353 mg/g DFM) was obtained at an optimum temperature of 28 °C; pH of 5.00; initial moisture content of 70% and incubation period of 12 days. This Lovastatin has the possibility to use in different therapeutic applications.
ABSTRACT
The present study aims to evaluate and validate a statistical model for maximizing biosurfactant productivity by Bacillus brevis using response surface methodology. In this respect, twenty bacterial isolates were screened for biosurfactant production using hemolytic activity, oil spreading technique, and emulsification index (E24). The most potent biosurfactant-producing bacterium (B. brevis) was used for construction of the statistical response surface model. The optimum conditions for biosurfactant production by B. brevis were: 33 °C incubation temperature at pH 8 for 10 days incubation period and 8.5 g/L glucose concentration as a sole carbon source. The produced biosurfactant (BS) (73%) exhibited foaming activity, thermal stability in the range 30-80 °C for 30 min., pH stability, from 4 to 9 and antimicrobial activity against (Escherichia coli). The BS gave a good potential application as an emulsifier.
ABSTRACT
A new local strain of S. cerevisiae F-514, for ethanol production during hot summer season, using Egyptian sugar cane molasses was applied in Egyptian distillery factory. The inouluum was propagated through 300 L, 3 m(3), and 12 m(3) fermenters charged with diluted sugar cane molasses containing 4%-5% sugars. The yeast was applied in fermentation vessels 65 m(3) working volume to study the varying concentrations of urea, DAP, orthophosphoric acid (OPA), and its combinations as well as magnesium sulfate and inoculum size. The fermenter was allowed to stay for a period of 20 hours to give time for maximum conversion of sugars into ethanol. S. cerevisiae F-514 at molasses sugar level of 18% (w/v), inoculum size of 20% (v/v) cell concentration of 3.0 × 10(8)/mL, and combinations of urea, diammonium phosphate (DAP), orthophosphoric acid (OPA), and magnesium sulfate at amounts of 20, 10, 5, and 10 kg/65 m(3) working volume fermenters, respectively, supported maximum ethanol production (9.8%, v/v), fermentation efficiency (FE) 88.1%, and remaining sugars (RS) 1.22%. The fermentation resulted 13.4 g dry yeast/L contained 34.6% crude protein and 8.2% ash. By selecting higher ethanol yielding yeast strain and optimizing, the fermentation parameters both yield and economics of the fermentation process can be improved.
