title: Using tobacco waste extract in pre-culture medium to improve xylose utilization for l-lactic acid production from cellulosic waste by Rhizopus oryzae.
abstract: The aim of this work was to study the high-titer l-lactic acid production from cellulosic waste using Rhizopus oryzae. The tobacco waste water-extract (TWE) added with 5g/L glucose and 0.1g/L vitamin C was optimized as pre-culture medium for R. oryzae. Results found that compared to traditional pre-culture medium, it improved xylose consumption rate up to 2.12-fold and enhanced l-lactic acid yield up to 1.73-fold. The highest l-lactic acid concentration achieved was 173.5g/L, corresponding to volumetric productivity of 1.45g/Lh and yield of 0.860g/g total reducing sugar in fed-batch fermentation. This process achieves efficient production of polymer-grade l-lactic acid from cellulosic feedstocks, lowers the cost of fungal cell pre-culture and provides a novel way for re-utilization of tobacco waste.
authors.affiliation: Bioengineering College, Chongqing University, Chongqing 400044, China; Research Center for Tobacco Bioengineering and Technology, Chongqing Science and Technology Commission, Yubei District, Chongqing 401147, China.
authors.forename: Yuxi
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Bioengineering College, Chongqing University, Chongqing 400044, China; Research Center for Tobacco Bioengineering and Technology, Chongqing Science and Technology Commission, Yubei District, Chongqing 401147, China.
authors.forename: Yuanliang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Research Center for Tobacco Bioengineering and Technology, Chongqing Science and Technology Commission, Yubei District, Chongqing 401147, China.
authors.forename: Jianrong
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Bioengineering College, Chongqing University, Chongqing 400044, China; Research Center for Tobacco Bioengineering and Technology, Chongqing Science and Technology Commission, Yubei District, Chongqing 401147, China. Electronic address: panj@cqu.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Pan
mesh_terms: D018929:Cell Culture Techniques / Q000379:methods; D003470:Culture Media / Q000737:chemistry*; D005285:Fermentation; D019344:Lactic Acid / Q000096:biosynthesis*; D012037:Refuse Disposal / Q000379:methods*; D012233:Rhizopus / Q000378:metabolism*; D014026:Nicotiana / Q000737:chemistry*; D014994:Xylose / Q000378:metabolism*
chemical_list: D003470:Culture Media; D019344:Lactic Acid; D014994:Xylose
keywords: Pre-culture; Rhizopus oryzae; Tobacco waste; Xylose; l-Lactic acid