Potential of Bacillus sp to produce polyhydroxybutyrate from biowaste

Aim: To test the Bacillus strains for their abilities to produce polyhydroxybutyrate (PHB) from different sugars and biowaste (Pea-shells). Methods and Results: Six Bacillus strains were checked for their ability to produce PHB from GM2 medium supplemented with different sugars at the rate of 1% (w/v) and from biowaste and GM2 (BW : M) combinations (3 : 7, I : 1, 7 : 3). Glucose supplemented GM2 medium resulted in maximum PHB production of 435 mg l(-1) constituting 31-62% w/w of the total cell dry mass. Substituting GM2 medium to the extent of 50% with biowaste (pea-shell slurry) resulted in 945-1205 mg l(-1) PHB (55-65% w/w). Optimization for additional nitrogen supplementation, inoculum size resulted in a final PHB production of 3010-3370 mg l(-1) equivalent to 300 g kg(-1) biowaste (dry wt). Conclusion: The Bacillus strains were able to produce PHB from biowaste (Pea-shells) as cheap source of substrate. Significance and Impact of the Study: This is the first report oil usage of pea-shells as feed for PHB production, opening new possibilities for its use for production of PHB and Bacillus as potential candidate for the purpose.