Complementary effect of combined bacterial-chemical pretreatment to promote enzymatic digestibility of lignocellulose biomass. (January 2019)

• Record Type: Journal Article
• Authors: Si, Mengying; Liu, Dan; Liu, Mingren; Yan, Xu; Gao, Congjie; Chai, Liyuan; Shi, Yan
• Is Part Of: Bioresource technology. Volume 272(2019)
• Page Start: 275
• Page End: 280
• Publication Date: 2019-01
• Subjects: Complementary effect -- Combination pretreatment -- Functional bacteria -- Delignification -- Decrystallization; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2018.10.036
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: Significant complementary effect existed in combined bacterial-chemical treatment. The complementary effect overcame the limitation of the chemical treatment. Saccharolytic bacteria enhanced the digestibility of the N-RS by decrystallization. Ligninolytic bacteria enhanced the digestibility of the H-RS by delignification. Abstract: Chemical pretreatment partially modified the structure of lignocellulose to enhance saccharification, leaving unaltered factors to limit further hydrolysis. To overcome these limitations, a biostrategy involving co-pretreatment combining bacteria with a chemical process was developed. A significant complementary effect was observed in specific co-pretreatments, e.g., ligninolytic bacteria enhanced acid pretreatment and saccharolytic bacteria enhanced alkaline pretreatment. Specifically, the ligninolytic bacterium Pandoraea sp. B-6 selectively removed the acidolysis-caused residual lignin and enhanced sugar release by 40.9% to 772.0 mg g −1 compared with that of acid-treated rice straw. After most of the lignin was removed, sugar release from alkali-treated RS was further improved by 31.8% to 820.2 mg g −1 via the saccharolytic bacterium Acinetobacter sp. B-2 through decrystallization. In the complementary mechanism, the active sites produced by chemical cleavage facilitated the bioprocess and further enhanced saccharification. This complementary mechanism provides a novel foundation for designing a rational combination pretreatment.