Production of Xylooligosaccharides from Steam Explosion Liquid of Napiergrass via Crossflow Filtration and Enzymatic Hydrolysis

• Main Authors: Tzu-Yang Lin, 林子暘
• Other Authors: 余琬琴
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/w2qcx3

碩士 === 國立臺北科技大學 === 有機高分子研究所 === 101 === Napiergrass (Pennisetum purpureum) is regarded as a potential energy crop and can be used for the production of fuels and chemicals. In Taiwan napiergrass juice has been used as a functional-food ingredient, whereas the fibrous residue of napiergrass can be converted into various products, including xylooligosaccharides, to increase its value. In this study, the fibrous residue of napiergrass was subjected to a steam explosion (SE) treatment to improve its enzymatic digestibility and to generate a liquid rich in xylooligosaccharides (XOs). Because the SE liquid contains various impurities, including organic acids, furfural and hydroxymethylfurfural (HMF), purification is required to obtain food-grade XOs. We employ crossflow nanofiltration (NF) to remove these impurities from the SE liquid, as well as concentrating the XO solution. The efficacy of a spiral-wound NF membrane module (DK1812C, GE-Osmonics) was evaluated. The SE liquid also contains water-soluble xylan, which can be enzymatically hydrolyzed into XOs to boost the yield of XOs. A commercially available endo-xylanase (from Thermomyces lanuginosus) was tested for this purpose. The effects of pH level, reaction time and enzyme loading on the production of XOs were investigated. The results show that the DK1812C membrane module could recover most of the XOs and efficiently remove acetic acid and furans from the SE liquid. The potential of the commercially available endo-xylanase to improve XO yield was confirmed.