P70: Sugar production from abandoned textile by enzymatic saccharification and application to ethanol fermentation

In recent years, lignocellulosic biomass is widely regarded as attractive feedstock for bioethanol production because of the most abundant, renewable and non-food source. However, pretreatment process is necessary for lignocellulosic biomass to utilize fermentable sugar and it is still a major technical, economical barrier for bioethanol commercialization. Our research group was searching for biomass feedstock focused on without pretreatment and interested in the dumped clothes, finally. In this study, cotton textiles were used not only substrate of enzymatic saccharification but also feedstock of ethanol fermentation. At first, three kinds of cotton were selected by characteristic such as color, density of strand, surface roughness. Composition analysis of cotton textiles were carried out according to the NREL analytical procedures and glucan composition was as follows; 87.66±2.33 of cotton-A, 97.24±1.55 of cotton-B, 93.93±1.70 of cotton-C. Saccharification was performed at 50 °C with Celluclast1.5L and Novozyme188 as biocatalysts and the results of glucose conversion was as follows; 86.9±0.6 of cotton-A, 68.5±0.4 of cotton-B, 82.6±2.2 of cotton-C at 48 hr. Pretreatment by dilute acid was investigated to confirm the effect and the fundamental experiment design was as follows; 121 °C of temperature, 1, 4% of acid concentration, 20, 60 min of reaction time. The results of glucose conversion was increased above 3~10% in general. However, the pretreatment was shown that economically infeasible and expected effect was lower due to the standards have already high conversion rate. Finally, simultaneous saccharification and fermentation (SSF) for ethanol production was performed by Saccharomyces cerevisiae K35 strain at optimized conditions.