Biofuel synthesis from the chitin and its derivatives extracted from the American cockroach Periplaneta americana Linnaeus (Family: Blattidae)

Abstract

In searching for new renewable resources alternative for fossil fuels, certain strains of fungi belonging to the genus Mucor was found to produce bioethanol from chitin; which is the main constituent of the insect exoskeleton. In the present study, a new simple technique was developed for chitin extraction from the dried exoskeletons of the American cockroach Periplaneta americana via alkali digestion with 4% NaOH. The extracted chitin was characterized physiochemically by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Elemental analysis (EA) and scanning electron microscope (SEM), compared with shrimp and crab chitin commercial samples. The properties of the one-step extracted chitin were similar to the standard samples in most characteristics. The extracted chitin was used for bioethanol production in a submerged fermentation system using the spores’ inoculums of two Mucor strains native to Egypt; M. circinelloides 6017 (isolated from Honey bee, Egypt, 2009, A. M. Moharram) and M. circinelloides 6027 (isolated from Cow dung, Egypt, 2009, A. M. Moharram). M. circinelloides 6017 yielded 11.22 ±0.312 g/l ethanol from 15 g/l colloidal chitin extracted from P. americana (74% of the initial cockroach colloidal chitin biotransformed to ethanol) after 6 days of incubation at an initial pH value 4 of the production medium. Such results highlighted the insects’ biomass as new, and promising alternative renewable source for biofuels which may help in solving energy problems.