Effect of precultural and nutritional parameters on compactin production by solid-state fermentation.

In the present study, production of compactin by Penicillium brevicompactum WA 2315 was studied. In the first step, various precultural parameters were studied by substituting one factor at a time. Subsequently, the effect of maltodextrin DE 18 on compactin production was studied. The optimized parameters gave maximum compactin production of 850 mug/gds as compared with 678 mug/gds before optimization. Statistical study was performed to further improve the production and develop a robust model. An improved yield of 950 mug/gds was obtained using the conditions proposed by the experimental model. The present study emphasizes the importance of precultural and nutritional parameters on the production of compactin, and further confirms the usefulness of solid-state fermentation for the production of industrially important secondary metabolites. It also confirms that complex nitrogen sources such as oil cakes can be used for the production of compactin.

A novel medium for the enhanced production of cyclosporin A by Tolypocladium inflatum MTCC 557 using solid state fermentation.

Cyclosporin A (CyA) produced by Tolypocladium inflatum is a promising drug owing to its immunosuppressive and antifungal activities. From an industrial point of view, the necessity to obtain a suitable and economic medium for higher production of CyA was the aim of this work. The present study evaluated the effect of different fermentation parameters in solid state fermentation, such as selection of solid substrate, hydrolysis of substrates, initial moisture content, supplementation of salts, additional carbon, and nitrogen sources, as well as the inoculum age and size, on production of CyA by Tolypocladium inflatum MTCC 557. The fermentation was carried out at 25+/-2 degrees for 9 days. A combination of hydrolyzed wheat bran flour and coconut oil cake (1:1) at 70% initial moisture content supported a maximum production of 3,872+/-156 mg CyA/kg substrate as compared with 792+/-33 mg/kg substrate before optimization. Furthermore, supplementation of salts, glycerol (1%w/w), and ammonium sulfate (1%w/w) increased the production of CyA to 5,454+75 mg/kg substrate. Inoculation of 5 g of solid substrate with 6 ml of 72-h-old seed culture resulted in a maximum production of 6,480+95 mg CyA/kg substrate.

Immobilization of Streptomyces clavuligerus on loofah sponge for the production of clavulanic acid.

Clavulanic acid, a naturally occurring powerful inhibitor of bacterial beta-lactamases, is produced by Streptomyces clavuligerus. The high void volume, permeability, and low cost of fibrous matrices prompted the use of Luffa cylindrica as a matrix for the immobilization of S. clavuligerus for the production of clavulanic acid. Immobilization of S. clavuligerus onto loofah sponge discs was studied with respect to the optimization of the inoculum size (number of discs) and its reusability for clavulanic acid production. Best yield of 1125 microg ml(-1) clavulanic acid was reached with two discs of loofah sponge (each approximately 0.136 g dry weight) and 120 h duration in the first cycle. Data obtained during four reusable cycles showed reduction in the initiation time of clavulanic acid production, resulting in higher levels of clavulanic acid in shorter time duration. Immobilization of S. clavuligerus on to loofah sponge discs, therefore, permit repeated reuse under the specified fermentation conditions for clavulanic acid production.

Production of cephamycin C by Streptomyces clavuligerus NT4 using solid-state fermentation.

Cephamycin C is an extracellular broad spectrum beta-lactam antibiotic produced by Streptomyces clavuligerus, S. cattleya and Nocardia lactamdurans. In the present study, different substrates for solid-state fermentation were screened for maximum cephamycin C production by S. clavuligerus NT4. The fermentation parameters such as substrate concentration, moisture content, potassium dihydrogen phosphate, inoculum size and ammonium oxalate were optimized by response surface methodology (RSM). The optimized conditions yielded 21.68 +/- 0.76 mg gds(-1) of cephamycin C as compared to 10.50 +/- 1.04 mg gds(-1) before optimization. Effect of various amino acids on cephamycin C production was further studied by using RSM, which resulted in increased yield of 27.41 +/- 0.65 mg gds(-1).