การผลิตไซโลโอลิโกแซคคาไรด์จากขี้เลื่อยไม้ยางพารา

Abstract

Commercial xylooligosaccharides (XOS) is produced from corn cob, birchwood and larch wood. In this study rubber wood sawdust was selected as a rawmaterial obtained from rubber wood processing. The result showed that the swellingrate of rubber wood sawdust was highest at 60°C for 3 hours. The effect of extractionsolvents of xylan was studied and it was found that 24%KOH + 1%NaBH4 gave higherxylanthan extraction by acetic under steam and high pressure. And extraction byalkaline at ambient temperature gave the highest xylan (70.54 mg/ml). The extractionby using 2.5% acetic acid at 2000°C for 120 minute gave the highest xylan (2.007mg/ml) and it was found that 5% acetic acid was used at 150°C for 120 minute gave1.993 mg/ml of xylan so there are not significantly difference (p>0.05). The extractionby using acetic acid also gave XOS at 150°C with 5% acetic acid that gave the highestXOS (40.522 mg/ml). Xylan obtained by alkaline extraction was further hydrolyzed byxylanase. It was found that XOS obtained had several DP.The optimal conditions on hydrolysis of xylan by xylanase were 100 U/ml, 6hours at 30°C It could hydrolysis xylan to several XOs that werexyloglucanoligosacharide 139.44 mg/ml, xylopentaose 881.53 mg/ml, xylotriose979.58 mg/ml, xylobiose 741.41 mg/ml and xylose 1334.38 mg/ml. XOS was purifiedby removed of xylan using ultrafiltration membrane (10 KDa). It was found thatmembrane filtration with diafiltration by water to sample at 3:1 for 120 minutes.Xylan was completely removed by membrane filtration together with diafiltration. Itwas found that remove xylose was removed for 97.83% the partial XOS wasdecreased XOS in permeate was further purified by ultrafiltration (1KDa). Xylobiose,xylotriose, xylopentaose and xyloglucanoligosaccharide were decreased andremained at 55.24, 53.51, 61.32 and 60.81% of initial concentration, respectively.