Open AccessEnhancement of Cellulose Degradation by Cattle Saliva
Author(s) -
Yasutaka Seki,
Yukiko Kikuchi,
Yuichi Kimura,
Ryo Yoshimoto,
Masatoshi Takahashi,
Kenichi Aburai,
Yoshihiro Kanai,
Tatsushi Ruike,
Kazuki Iwabata,
Fumio Sugawara,
Hideki Sakai,
Masahiko Abe,
Kengo Sakaguchi
Publication year - 2015
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0138902
Subject(s) - cellulose , saliva , cellulase , hydrolysis , chemistry , reducing sugar , sugar , food science , degradation (telecommunications) , biochemistry , telecommunications , computer science
Saccharification of cellulose is a promising technique for producing alternative source of energy. However, the efficiency of conversion of cellulose into soluble sugar using any currently available methodology is too low for industrial application. Many additives, such as surfactants, have been shown to enhance the efficiency of cellulose-to-sugar conversion. In this study, we have examined first whether cattle saliva, as an additive, would enhance the cellulase-catalyzed hydrolysis of cellulose, and subsequently elucidated the mechanism by which cattle saliva enhanced this conversion. Although cattle saliva, by itself, did not degrade cellulose, it enhanced the cellulase-catalyzed degradation of cellulose. Thus, the amount of reducing sugar produced increased approximately 2.9-fold by the addition of cattle saliva. We also found that non-enzymatic proteins, which were present in cattle saliva, were responsible for causing the enhancement effect. Third, the mechanism of cattle saliva mediated enhancement of cellulase activity was probably similar to that of the canonical surfactants. Cattle saliva is available in large amounts easily and cheaply, and it can be used without further purification. Thus, cattle saliva could be a promising additive for efficient saccharification of cellulose on an industrial scale.