title: Conversion of red-algae Gracilaria verrucosa to sugars, levulinic acid and 5-hydroxymethylfurfural.
abstract: This study employed a statistical methodology to investigate the optimization of conversion conditions and evaluate the reciprocal interaction of reaction factors related to the process of red-algae Gracilaria verrucosa conversion to sugars (glucose, galactose), levulinic acid and 5-hydroxymethylfurfural (5-HMF) by acidic hydrolysis. Overall, the conditions optimized for glucose formation included a higher catalyst concentration than did those for galactose, and these conditions for galactose were similar to those for 5-HMF. Levulinic acid production, meanwhile, was optimized at a higher reaction temperature, a higher catalyst concentration, and a longer reaction time than was glucose, galactose or 5-HMF production. By this approach, the optimal yields (and reaction conditions) for glucose, galactose, levulinic acid, and 5-HMF were as follows: glucose 5.29 g/L (8.46 wt%) (reaction temperature 160 °C, catalyst concentration 1.92%, reaction time 20 min), galactose 18.38 g/L (29.4 wt%) (160 °C, 1.03%, 20 min), levulinic acid 14.65 g/L (18.64 wt%) (180.9 °C, 2.85%, 50 min), and 5-HMF 3.74 g/L (5.98 wt%) (160.5 °C, 1%, 20 min).
authors.affiliation: Department of Biotechnology, Pukyong National University, Busan, 608-737, South Korea, gtjeong@pknu.ac.kr.
authors.forename: Gwi-Taek
authors.initials: GT
authors.lastname: Jeong
authors.forename: Chae Hun
authors.initials: CH
authors.lastname: Ra
authors.forename: Yong-Ki
authors.initials: YK
authors.lastname: Hong
authors.forename: Joong Kyun
authors.initials: JK
authors.lastname: Kim
authors.forename: In-Soo
authors.initials: IS
authors.lastname: Kong
authors.forename: Sung-Koo
authors.initials: SK
authors.lastname: Kim
authors.forename: Don-Hee
authors.initials: DH
authors.lastname: Park
mesh_terms: D019149:Bioreactors / Q000382:microbiology*; D018929:Cell Culture Techniques / Q000379:methods; D003198:Computer Simulation; D005662:Furaldehyde / Q000031:analogs & derivatives* / Q000378:metabolism; D005690:Galactose / Q000096:biosynthesis*; D005947:Glucose / Q000096:biosynthesis*; D006868:Hydrolysis; D007982:Levulinic Acids / Q000378:metabolism*; D008954:Models, Biological; D015233:Models, Statistical; D000461:Rhodophyta / Q000145:classification / Q000378:metabolism*; D013045:Species Specificity; D013696:Temperature
chemical_list: D007982:Levulinic Acids; C008046:5-hydroxymethylfurfural; D005662:Furaldehyde; D005947:Glucose; C032246:levulinic acid; D005690:Galactose