Compactin Production Studies Using <Emphasis Type="Italic">Penicillium brevicompactum</Emphasis> Under Solid-State Fermentation Conditions

In the present study, compactin production by Penicillium brevicompactum WA 2315 was optimized using solid-state fermentation. The initial one factor at a time approach resulted in improved compactin production of 905 μg gds⁻¹ compared to initial 450 μg gds⁻¹. Subsequently, nutritional, physiological, and biological parameters were screened using fractional factorial and Box–Behnken design. The fractional factorial design studied inoculum age, inoculum volume, pH, NaCl, NH₄NO₃, MgSO₄, and KH₂PO₄. All parameters were found to be significant except pH and KH₂PO₄. The Box–Behnken design studied inoculum volume, inoculum age, glycerol, and NH₄NO₃ at three different levels. Inoculum volume (p = 0.0013) and glycerol (p = 0.0001) were significant factors with greater effect on response. The interaction effects were not significant. The validation study using model-defined conditions resulted in an improved yield of 1,250 μg gds⁻¹ compactin. Further improvement in yield was obtained using fed batch mode of carbon supplementation. The feeding of glycerol (20% v/v) on day 3 resulted in further improved compactin yield of 1,406 μg gds⁻¹. The present study demonstrates that agro-industrial residues can be successfully used for compactin production, and statistical experiment designs provide an easy tool to improve the process conditions for secondary metabolite production.