الفهرس | Only 14 pages are availabe for public view |
Abstract In the present investigation, The main objective of the present study was to optimize the conditions of the penicillin production by submerged fermentation using Aspergillus nidualans NRRL 4266 and Penicillium chrysogenum NRRL 824. It was found that Brakhage fermentation medium is the optimum medium for penicillin production is at pH range5-6, incubated at 28C with shaking velocity 150rpm using inoculums size 2%. Lactose supplementation 4% or Glucose:lactose ratio (3:1) significantly increases penicillin yield of P. chrysogenum. Through the study of the cell immobilization technique; loofa sponge can be regarded as a promising matrix for immobilization of P. chrysogenum during one or several fermentation techniques. It is also observed that higher penicillin production was obtained by solid state fermentation. Wheat bran was the most suitable substrate used for production of penicillin under optimized conditions. Finally, we present here evidence for the effect of repeated DNA and/or TE/TL elements in positive regulation of the penicillin gene cluster. Also, this work represents an advance toward understanding the complex regulation of secondary metabolite production and provides a platform for investigating a role for chromatin dynamics in SM diversity. Pragmatically, the manipulation of PbIa-like elements in filamentous fungi may enable a technological means to increase production of beneficial metabolites including penicillin or decrease production of harmful toxins. |