Low lignin solubility in aqueous solution is one of the major bottlenecks for lignin biodegradation and bioconversion.Alkaline solution contributes to improving lignin solubility,whereas most microbes can not survive ...Low lignin solubility in aqueous solution is one of the major bottlenecks for lignin biodegradation and bioconversion.Alkaline solution contributes to improving lignin solubility,whereas most microbes can not survive in alkaline conditions.Herein,lignin dissolution behaviors in different pH solutions were systematically investigated,which indicated that solution pH above 10.5 contributed to high solubility of alkali lignin.To match with alkaline lignin aqueous system,several alkali-tolerant ligninolytic bacteria were isolated,most of which are distinct to previously reported ones.Then,the ligninolytic capabilities of these isolates were assessed in different pH conditions by determining their assimilation on alkali lignin,lignin-derived monomers and dimers,their decolorization capabilities,and their lignin peroxidase activities.Thereafter,the underlying ligninolytic and alkali-tolerant mechanisms of Sutcliffiella sp.NC1,an alkalophilic bacterium,was analyzed on the basis of its genome information.The results not only provide valuable information for lignin biodegradation and lignin valorization,but also expand knowledge on alkali-tolerant bacteria.展开更多
Lignin is the most abundant heteropolymer based on aromatic subunits in nature.Large quantities of lignin are annually produced from pulping processes and biorefinery industries.Its unclearly defined structure and dif...Lignin is the most abundant heteropolymer based on aromatic subunits in nature.Large quantities of lignin are annually produced from pulping processes and biorefinery industries.Its unclearly defined structure and difficult biodegradation mainly limit its utilization.This work focused on the effect of hydroxylation of lignin on its microbial degradation.Butyloxy carbonyl-modified lignin,and hydroxylated-lignin were synthesized with di-tert-butyl dicarbonate and hydrogen peroxide,respectively,using lignin as raw material.The degradation of the modifiedlignins both by P.chrysosporium and B.subtilis were analyzed using UV-vis spectroscopy.Results revealed that the lignin degradation velocity raises with the increase hydroxylation level of lignin.Moreover,FTIR and 1H NMR analysis of the biodegradation products of lignin further indicated that higher content of hydroxyl groups in lignin facilitated the demethylation combined with the aromatic ring cracking in the presence of fungus and bacteria.展开更多
基金National Key R&D Program of China(No.2021YFC2101301)National Natural Science Foundation of China(No.22278227).
文摘Low lignin solubility in aqueous solution is one of the major bottlenecks for lignin biodegradation and bioconversion.Alkaline solution contributes to improving lignin solubility,whereas most microbes can not survive in alkaline conditions.Herein,lignin dissolution behaviors in different pH solutions were systematically investigated,which indicated that solution pH above 10.5 contributed to high solubility of alkali lignin.To match with alkaline lignin aqueous system,several alkali-tolerant ligninolytic bacteria were isolated,most of which are distinct to previously reported ones.Then,the ligninolytic capabilities of these isolates were assessed in different pH conditions by determining their assimilation on alkali lignin,lignin-derived monomers and dimers,their decolorization capabilities,and their lignin peroxidase activities.Thereafter,the underlying ligninolytic and alkali-tolerant mechanisms of Sutcliffiella sp.NC1,an alkalophilic bacterium,was analyzed on the basis of its genome information.The results not only provide valuable information for lignin biodegradation and lignin valorization,but also expand knowledge on alkali-tolerant bacteria.
基金This work was financially supported by the Science and Technology Innovation Program of Hunan Province(Contract Grant No.2018RS3101).
文摘Lignin is the most abundant heteropolymer based on aromatic subunits in nature.Large quantities of lignin are annually produced from pulping processes and biorefinery industries.Its unclearly defined structure and difficult biodegradation mainly limit its utilization.This work focused on the effect of hydroxylation of lignin on its microbial degradation.Butyloxy carbonyl-modified lignin,and hydroxylated-lignin were synthesized with di-tert-butyl dicarbonate and hydrogen peroxide,respectively,using lignin as raw material.The degradation of the modifiedlignins both by P.chrysosporium and B.subtilis were analyzed using UV-vis spectroscopy.Results revealed that the lignin degradation velocity raises with the increase hydroxylation level of lignin.Moreover,FTIR and 1H NMR analysis of the biodegradation products of lignin further indicated that higher content of hydroxyl groups in lignin facilitated the demethylation combined with the aromatic ring cracking in the presence of fungus and bacteria.