| Summary: | <p>Abstract</p> <p>Background</p> <p>Bioethanol isolated from lignocellulosic biomass represents one of the most promising renewable and carbon neutral alternative liquid fuel sources. Enzymatic saccharification using cellulase has proven to be a useful method in the production of bioethanol. The filamentous fungi <it>Acremonium cellulolyticus </it>and <it>Trichoderma reesei </it>are known to be potential cellulase producers. In this study, we aimed to reveal the advantages and disadvantages of the cellulase enzymes derived from these fungi.</p> <p>Results</p> <p>We compared <it>A. cellulolyticus </it>and <it>T. reesei </it>cellulase activity against the three lignocellulosic materials: eucalyptus, Douglas fir and rice straw. Saccharification analysis using the supernatant from each culture demonstrated that the enzyme mixture derived from <it>A. cellulolyticus </it>exhibited 2-fold and 16-fold increases in Filter Paper enzyme and β-glucosidase specific activities, respectively, compared with that derived from <it>T. reesei</it>. In addition, culture supernatant from <it>A. cellulolyticus </it>produced glucose more rapidly from the lignocellulosic materials. Meanwhile, culture supernatant derived from <it>T. reesei </it>exhibited a 2-fold higher xylan-hydrolyzing activity and produced more xylose from eucalyptus (72% yield) and rice straw (43% yield). Although the commercial enzymes Acremonium cellulase (derived from <it>A. cellulolyticus</it>, Meiji Seika Co.) demonstrated a slightly lower cellulase specific activity than Accellerase 1000 (derived from <it>T. reesei</it>, Genencor), the glucose yield (over 65%) from lignocellulosic materials by Acremonium cellulase was higher than that of Accellerase 1000 (less than 60%). In addition, the mannan-hydrolyzing activity of Acremonium cellulase was 16-fold higher than that of Accellerase 1000, and the conversion of mannan to mannobiose and mannose by Acremonium cellulase was more efficient.</p> <p>Conclusion</p> <p>We investigated the hydrolysis of lignocellulosic materials by cellulase derived from two types of filamentous fungi. We found that glucan-hydrolyzing activity of the culture supernatant from <it>A. cellulolyticus </it>was superior to that from <it>T. reesei</it>, while the xylan-hydrolyzing activity was superior for the cellulase from <it>T. reesei</it>. Moreover, Acremonium cellulase exhibited a greater glucan and mannan-hydrolyzing activity than Accellerase 1000.</p>
|
|---|
