นโยบายงานวิจัย /จรรยาบรรณนักวิจัย /ระดับคุณภาพบทความวิจัยตีพิมพ์ /ระดับคุณภาพผลงานวิชาการ /แหล่งทุน /ดาวน์โหลด /ฐานข้อมูลวิจัย /วิเคราะห์-สังเคราะห์งานวิจัย /ลิขสิทธิ์ /ข่าว


Optimization of sodium hydroxide pretreatment and enzyme loading for efficient hydrolysis of rice straw to improve succinate production by metabolically engineered Escherichia coli KJ122 under simultaneous saccharification and fermentation

Author

-

Apichai Sawisit, Surawee Jampatesh, Sirima Suvarnakuta Jantama,

Kaemwich Jantama


Journal

- Bioresource Technology

Volume

- 260

Year

- 2018

Publication type

- Research article (Inter)

Page list

- 348-356

Abstract

   

Rice straw was pretreated with sodium hydroxide (NaOH) before subsequent use for succinate production by Escherichia coli KJ122 under simultaneous saccharification and fermentation (SSF). The NaOH pretreated rice straw was significantly enhanced lignin removal up to 95%. With the optimized enzyme loading of 4% cellulase complex+0.5% xylanase (endo-glucanase 67 CMC-U/g, β-glucosidase 26 pNG-U/g and xylanase 18 CMC-U/g dry biomass), total sugar conversion reached 91.7 ± 0.8% (w/w). The physicochemical analysis of NaOH pretreated rice straw indicated dramatical changes in its structure, thereby favoring enzymatic saccharification.
In batch SSF, succinate production of 69.8 ± 0.3 g/L with yield and productivity of 0.84 g/g pretreated rice straw and 0.76 ± 0.02 g/L/h, respectively, was obtained. Fed-batch SSF significantly improved succinate concentration and productivity to 103.1 ± 0.4 g/L and 1.37 ± 0.07 g/L/h with a comparable yield. The results demonstrated a feasibility of sequential saccharification and fermentation of rice straw as a promising process
for succinate production in industrial scale.
 


Keywords

   

Rice straw, Succinate, Metabolic engineering, Escherichia coli, 

Simultaneous saccharification and fermentation