title: Fermentative production of high titer citric acid from corn stover feedstock after dry dilute acid pretreatment and biodetoxification.
abstract: The aim of this work is to study the citric acid fermentation by a robust strain Aspergillus niger SIIM M288 using corn stover feedstock after dry dilute sulfuric acid pretreatment and biodetoxification. Citric acid at 100.04g/L with the yield of 94.11% was obtained, which are comparable to the starch or sucrose based citric acid fermentation. No free wastewater was generated in the overall process from the pretreatment to citric acid fermentation. Abundant divalent metal ions as well as high titer of potassium, phosphate, and nitrogen were found in corn stover hydrolysate. Further addition of extra nutrients showed no impact on increasing citric acid formation except minimum nitrogen source was required. Various fermentation parameters were tested and only minimum regulation was required during the fermentation. This study provided a biorefining process for citric acid fermentation from lignocellulose feedstock with the maximum citric acid titer and yield.
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.
authors.forename: Ping-Ping
authors.initials: PP
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.
authors.forename: Jiao
authors.initials: J
authors.lastname: Meng
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China. Electronic address: jbao@ecust.edu.cn.
authors.forename: Jie
authors.initials: J
authors.lastname: Bao
mesh_terms: D001234:Aspergillus niger / Q000378:metabolism*; D001709:Biotechnology / Q000379:methods*; D019343:Citric Acid / Q000378:metabolism*; D005285:Fermentation; D008031:Lignin / Q000378:metabolism; D018520:Plant Shoots / Q000378:metabolism; D013213:Starch / Q000378:metabolism; D013395:Sucrose / Q000378:metabolism; D013464:Sulfuric Acids / Q000737:chemistry; D062065:Wastewater; D003313:Zea mays / Q000378:metabolism*
chemical_list: D019343:Citric Acid; D008031:Lignin; D013213:Starch; D013395:Sucrose; D013464:Sulfuric Acids; D062065:Wastewater; C036909:lignocellulose; C033158:sulfuric acid
keywords: Aspergillus niger; Biodetoxification; Citric acid; Lignocellulose; Zero nutrients requirement