Cocoa Bean Shell as Promising Feedstock for the Production of Poly(3-hydroxybutyrate) (PHB)

Cocoa bean shell (CBS), a by-product of the chocolate industry, has been employed as substrate to obtain poly(3-hydroxybutyrate) (PHB) by fermentation with Bacillus firmus. With this aim, acid-thermal hydrolysis CBS (20% w/v) was conducted at 135 °C for 10 min so that broths rich in fermentable sugars were obtained. These broths, both non-centrifuged and centrifuged, media. Significant polymer production obtained from broth solids (non-centrifuged) yield 107 mg PHB/g dry matter. results indicated presence played an important role microorganism metabolism, them being fundamental PHB. Experimental data fitted model based on irreversible first-order reactions, kinetic constants solubilisation, hydrolysis, sugar consumption. Although, several studies obtaining PHB other agri-food residues have published, is first work CBS, study promising concentrations similar or even higher than others previously reported.