초록
<P>For a resolution of reducing carbon dioxide emission and increasing food production to respond to the growth of global population, production of biofuels from non-edible biomass is urgently required. Abundant orange wastes, such as peel and strained lees, are produced as by-product of orange juice, which is available non-edible biomass. However, <SMALL>D</SMALL>-limonene included in citrus fruits often inhibits yeast growth and makes the ethanol fermentation difficult. This study demonstrated that isopropanol-butanol-ethanol fermentation ability of <I>Clostridium beijerinckii</I> and cellulosic biomass degrading ability of <I>C. cellulovorans</I> were cultivated under several concentrations of limonene. As a result, <I>C. cellulovorans</I> was able to grow even in the medium containing 0.05% limonene (v/v) and degraded 85% of total sugar from mandarin peel and strained lees without any pretreatments. More interestingly, <I>C. beijerinckii</I> produced 0.046 g butanol per 1 g of dried strained lees in the culture supernatant together with <I>C. cellulovorans</I>.</P>