室内饲养与野外台湾乳白蚁木质纤维素水解酶活性的比较研究

以台湾乳白蚁Coptotermes formosanus Shiraki的室内群体与野外群体为研究对象,测定工蚁体内4种糖基水解酶和滤纸酶活(FPA)的活力大小及分布。结果表明:内切-β-1,4-葡聚糖酶(EG)、β-葡萄糖苷酶(BG)、外切-β-1,4-葡聚糖酶(CBH)、内切-β-1,4-木聚糖酶(EX)及FPA的活性在不同组织中有较大差异。两类群体的BG、EX及CBH有相似分布,BG和EX分别高度集中于中肠和后肠,CBH主要在中肠及后肠分布。FPA和EG在两类群体中有不同分布,室内群体的主要在中肠,野外群体的则集中于后肠。两类群体各种酶活力大小顺序同为:EX>EG≥BG>CBH。此外,室内饲养群体的大小及年限对台湾乳白蚁木质纤维素酶活力无显著影响。

Comparative study of the activity of lignocellulolytic enzymes in captive and field colonies of Coptotermes formosanus

Workers of Coptotermes formosanus Shiraki were collected from captive and field colonies. The activity of 4 kinds of glycoside hydrolase, and filter paper enzyme activity （FPA） , were determined in different tissues including the salivary gland/foregut, midgut, hindgut and integument. The results show that the activities of glycoside hydrolase and FPA varied in different tissues. β-1,4-D-glucosidase （BG） , endo-β-1,4-xylanase （EX） and exo-1, 4-β-D-glucanase （CBH） were distributed similarly in both captive and field colonies. BG and EX were mostly located in the midgut and hindgut, respectively, whereas the highest CBH activity was observed in the midgut and hindgut. Endo-1, 4-β-glucanase （EG） and FPA had different distributions in insects from the two types of colonies; concentrated in the midgut in insects from captive colonies but mainly located at the hindgut in those from fiecd colonies. The relative activity of each glycoside hydrolase in both types of colonies was, in descending order, EX 〉 EG ≥ BG 〉 CBH. In addition, feeding size and age had no significant influence on the activities of lignocellulolytic enzymes in C. formosanus.