【摘要】：以玉米淀粉為原材料,利用生物酶解法制備多孔淀粉,并以聚乙烯亞胺(PEI)為表面改性劑,以戊二醇(GA)為交聯(lián)劑,對多孔淀粉進行交聯(lián)改性。以沉降積為指標(biāo),優(yōu)化確定多孔淀粉改性的最佳工藝條件。利用Zeta電位儀檢測分析改性多孔淀粉顆粒表面的電荷分布情況,并通過掃描電子顯微鏡觀察改性多孔淀粉的外部形貌。α-淀粉酶和糖化酶的混合比例為1∶4,酶添加量為5%,反應(yīng)體系p H保持6左右,在45℃條件下酶催化反應(yīng)24h時,可制備出外部形態(tài)完整、表面分布較多孔洞的多孔淀粉。以GA為交聯(lián)劑,用PEI對多孔淀粉表面進行改性的最佳條件為:PEI添加量6%,GA添加量5%,35℃條件下攪拌反應(yīng)8h。此條件下制備的改性多孔淀粉,形態(tài)保持完整,沉降積表現(xiàn)最佳,且顆粒表面分布豐富的正電荷,等電點達到9.8。以表面改性的多孔淀粉為載體,在酸性條件下固定化大腸桿菌,制備了淀粉固定化大腸桿菌。
[Abstract]:The porous starch was prepared by enzymatic hydrolysis with corn starch as raw material. The porous starch was crosslinked with polyimide (PEI) as surface modifier and pentanediol (GA) as crosslinking agent. The optimum technological conditions for the modification of porous starch were optimized with sedimentation product as the index. The surface charge distribution of the modified porous starch was analyzed by Zeta potentiometer, and the external morphology of the modified porous starch was observed by scanning electron microscope. The mixed ratio of 偽 -amylase and Glucoamylase was 1: 4. Under the condition of enzyme catalytic reaction at 45 鈩，

本文編號：2402729