The utilization of fruit and vegetable wastes for bioethanol production with the inoculation of indigenous yeasts consortium

Dwi Wahyudha Wira, Febrin E. E. Sidabutar, Roostita Lobo Balia, Hanna Felina, Gemilang Lara Utama

Abstract: The aims of the study were to determine the utilization of fruit and vegetable wastes combination towards bioethanol production with the used of indigenous yeasts as starter. Banana, papaya and napa cabbage as dominates wastes were taken as materials from Central market around Bandung City. Candida krusei and Hanseniaspora guilliermondii were indigenous yeasts that isolated from wastes and determined as ethanol and glucose-tolerance isolates on preliminary research. The best ethanol fermenting activities of the isolates were tested into mixed wastes and resulted the consortium with ratio 1:1 of C. krusei and H. guilliermondii as the best starter with bioethanol production of 5.09% at 48 h fermentation. The isolates were grown in modified nutrient broth/NB (Oxoid Ltd.) with 3% yeast extract/YE (Kraft Foods) and 10 ppm amoxicillin for 48 h at room temperatures (23-28°C). Various fruit and vegetable wastes had been set into treatment combination of banana (W1), papaya (W2), napa cabbage (W3). Water was added for 1.5 times of wastes volumes and then mashed with blender until homogeny. Every treatment was inoculated with 3% of C. krusei and H. guilliermondii (1:1) then incubated for 72 h at room temperatures (23-28°C). The results shown the best bioethanol production gained by W1 at 24 h incubation with the bioethanol contents of 7.38% and the production of bioethanol tend to decrease after 24 h incubation.

Keywords: bioethanol; Candida krusei; fruit wastes; Hanseniaspora guilliermondii; vegetable wastes

Date published: 2019-04-04