Integration of a phenolic-acid recovery step in the CaCCO process for efficient fermentable-sugar recovery from rice straw.
An advanced sugar-platform bioprocess for lignocellulosic feedstocks by adding a phenolic-acid (PA: p-coumaric acid and ferulic acid) recovery step to the CaCCO process was designed. For efficient PA extraction, pretreatment was 95°C for 2h, producing a yield of 7.30 g/kg-dry rice straw (65.2% of total ester-linked PAs) with insignificant effects on saccharification. PAs were readily recovered in solution during the repeated washings of solids, and the glucose yield, after 72-h saccharification of the washed solids, was significantly improved from 65.9% to 70.3-72.7%, suggesting the removal of potential enzyme inhibitors. The promotion of xylose yield was insignificant, probably due to 13.1-17.8% loss of xylose residues after washing(s). This new bioprocess, termed the SRB (simultaneous recovery of by-products)-CaCCO process, would effectively produce fermentable sugars and other valuables from feedstocks, strengthening the platform in both economic and environmental terms.
National Food Research Institute, National Agriculture and Food Research Organization, 2-1-12 Kannondai, Tsukuba, Ibaraki 305-8642, Japan.
Rui
R
Zhao
Min-Soo
MS
Yun
Riki
R
Shiroma
Masakazu
M
Ike
Di
D
Guan
Ken
K
Tokuyasu
D001709:Biotechnology / Q000379:methods*; D002118:Calcium / Q000737:chemistry*; D017610:Calcium Compounds / Q000737:chemistry; D002241:Carbohydrates / Q000032:analysis*; D002244:Carbon / Q000737:chemistry*; D003373:Coumaric Acids / Q000032:analysis; D005285:Fermentation; D005947:Glucose / Q000032:analysis; D062385:Hydroxybenzoates / Q000032:analysis*; D012275:Oryza / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry; D011422:Propionates; D013696:Temperature; D014866:Waste Products; D014994:Xylose / Q000032:analysis
D017610:Calcium Compounds; D002241:Carbohydrates; D003373:Coumaric Acids; D062385:Hydroxybenzoates; D010087:Oxides; D011422:Propionates; D014866:Waste Products; D002244:Carbon; D014994:Xylose; C004999:ferulic acid; C016538:lime; C017616:phenolic acid; C495469:p-coumaric acid; D005947:Glucose; D002118:Calcium
CaCCO; Ferulic acid; Lime pretreatment; Rice straw; Saccharification; calcium capturing by carbonation; p-Coumaric acid