小麦秆特性的研究  

A Study on the Characterization of LCC in Wheat Straw (Triticum aestivum CV Yangmai No.4)

作　　者：蒋杏芬[1] 邰瓞生[1] 王佩卿[1] 

机构地区：[1]南京林业大学林产化学工程系木材化学教研室

出　　处：《中国造纸学报》1989年第1期1-9,共9页Transactions of China Pulp and Paper

摘　　要：本研究采用了Bjorkman制备LCC方法自杨麦4号分离出含有酚酸的LCC,并采用DEAE-SephadexA-25凝胶分级成三个级分,依次为M-LCC,A-LCC和RL-LCC。主要研究了后两个级分。Lignin-carbohydrate complex(LCC) containing ferulic and p-coumaric acids was isolated from milled wheat straw by Bjorkman method, and was separated into three fractions (M-LCC, A-LCC and RL-LCC) by gel filtration on DEAE-sephadex A-25. Two fractions (A-LCC and RL-LCC) were investigated by physical and chemical methods. When treated with trifluoroacetic acid, hemicellulose in LCCs was hydrolysed to form arabinose, xylose, mannose,galactose and glucose(in relative ratios of 10.56:77.69:1.26:4.99:5.50 for A-LCC and 10.36:71.06:1.00:5.12:12.19 for RL-LCC). The molar ratios of arabinose to xylose were 1.4/10 for A-LCC and 1.5/10 for RL-LCC respectively, higher than that for hemicellulose(1.0/10) in wheat straw whole stalk Uronic acid contents were determined with carbazole method,and were 9.10% for A-LCC and 7.42% for RL-LCC. The results showed that uronic acid content in LCCs was higer than that in hemicellulose from wheat straw (7.38%), suggesting the existance of pectin substances. According to elemental analysis, nitrogen contents up to 0.03% (for A-LCC) and 0.48% (for RL-LCC) weve found. It was suggested that RL-LCC came mainly from the primary cell wall and A-LCC came mainly from the secondary cell wall. On oxidation with NalO_4, oxopolysaccharide was obtained. It released ethylene glycol, glycerol, xylose and hexose. Analysis showed that about 70-80% D-xylose was oxidized by the periodate, indicating that about 20-30 % D-xylose was bonded at C_2, or C_3. or C_2, C_3. More arabinose unit as side chains rather than xylan existed in the carbohydrate fractions of the wheet straw LCC. LCCs were enzymatically degraded by Meicelase p-I and formed enzyme preparation products (EPP).On acid hydrolysis. EPPs released sugars. Analytical results indicated that EPPs were rich in arabinose, the arabinose to xylose molar ratios being 1.57/10forA- LCC and 2.15/10 for RL-LCC. It was suggested that lignin was partially bonded to carbohydrate by the arabinose side chain of xylan. Alkaline nitrobenzene oxidation gaveV:S:H molar rat

关 键 词：小麦 麦秆 特性 分级 酚酸 分离 研究 制备 凝胶 

分 类 号：TS959.2[轻工技术与工程] S512.1[农业科学—作物学]