Phorbol Esters Degradation and Enzyme Production by Bacillus using Jatropha Seed Cake as Substrate

The purposes of this research were to evaluate phorbol esters (PEs) degradation rate and enzyme production yield using submerged fermentation (SMF) as screening method and further using solid-state fermentation (SSF) as pilot scale-up study. SMF was carried out with 20 g seed cake in 100 ml minimal salt medium for 7 days incubation, while SSF was done with 20 g seed cake at 50% moisture content for 9 days incubation. Bacillus strains grew well on J. curcas seed cake with 108-1011 CFU/ ml in SMF for 3 days incubation, while they were 108-1010 CFU/ g in SSF. PEs reduced 76.5%, 77.1%, 78.4%, 85.5%, and 92.0% in SMF with B. smithii G16, B. sonorensis D12, B. licheniformis A3, B. subtilis H8 and B. coagulans C45 for 3 days incubation, respectively, and PEs completed degraded by these five strains for 7 days incubation. Maximum amylase, cellulase, lipase, pectinase, protease and xylanase productions in SMF were observed in B. sonorensis D12 (5.49 ± 0.49 U/ ml; day 7), B. subtilis H8 (17.03 ± 4.90 U/ ml; day 2), B. licheniformis A3 (59.03 ± 0.26 U/ ml; day 7), B. sonorensis D12 (1.70 ± 0.04 U/ ml; day 3), B. coagulans C45 (15.95 ± 0.35 U/ ml; day 7) and B. smithii G16 (1.40 ± 0.01 U/ ml; day 3), respectively. For SSF, PEs were reduced 86.0%, 83.2%, and 93.0% with B. sonorensis D12, B. subtilis H8 and B. smithii G16 for 3 days incubation, respectively. Maximum amylase, cellulase, lipase, pectinase, protease and xylanase productions in SSF were observed in B. smithii G16 (16.08 ± 0.36 U/ g; day 4), B. sonorensis D12 (2.94 ± 0.06 U/ g; day 2), B. smithii G16 (3.87 ± 0.64 U/ g; day 4), B. sonorensis D12 (8.13 ± 1.06 U/ g; day 2), B. smithii G16 (14.13 ± 0.30 U/ g; day 4) and B. smithii G16 (9.72 ± 0.97 U/ g; day 3), respectively. J. curcas seed cake could be detoxified by Bacillus and the high-protein seed cake could be potentially used for enzyme production in industry.