短时高温胁迫对中华地鳖蛋白质和氨基酸含量的影响

Effects of short-time high-temperature stress on protein and amino acid content in Eupolyphaga sinensis Walker

土鳖虫体内富含蛋白质和氨基酸,是一种重要的药用昆虫。高温对昆虫生命活动产生重要影响。为探明短时高温胁迫对土鳖虫体内蛋白质和氨基酸含量的影响,本试验以中华地鳖Eupolyphaga sinensis Walker 8龄雌若虫为研究对象,通过人工设置29℃、33℃、37℃为高温处理组,以25℃为对照,测定2 h短时高温胁迫对中华地鳖存活率以及体内蛋白质和氨基酸含量的影响。结果表明:29℃、33℃和37℃短时高温处理对中华地鳖存活率无影响,蛋白质含量分别为76.57%±3.29%、79.60%±0.92%、77.00%±0.71%,与对照(84.50%±1.57%)相比均明显下降;短时高温处理后,29℃处理组土鳖虫总氨基酸含量为206.97±7.42 mg/g,6种人体必需的游离氨基酸苏氨酸8.23±0.32 mg/g,甲硫氨酸3.98±0.49 mg/g,异亮氨酸8.27±0.35 mg/g,亮氨酸16.38±0.86 mg/g,苯丙氨酸8.34±0.40 mg/g,以及赖氨酸12.56±0.64 mg/g的含量较对照和33℃、37℃高温处理组均显著升高,表明29℃短时高温处理可显著提高中华地鳖体内人体必需游离氨基酸含量。本研究是国内外对高温胁迫下药用昆虫体内活性成分的首次报道,研究结果将为进一步明确高温对土鳖虫的药用价值的影响,以及为土鳖虫人工养殖条件提供理论依据。

The ground beetle is an important medicinal insect rich in protein and amino acid.Previous research had shown that high temperature had an important effect on insect life.In this study,in order to determine the effects of a short-time high-temperature stress on the content of protein and amino acids in the ground beetle body,8-instar female nymphs of Eupolyphaga sinensis Walker was used as research material.Three high-temperature groups,including 29℃,33℃,and 37℃,were manualy set.Using 25℃as a control,the effects of short-time(2 h)of high-temperature stress on the survival rate and protein and amino acid content were determined.Results showed that the survival rate of ground beetle was not affected by high-temperature treatment at 29℃,33℃,and 37℃.The protein content in E.sinensis was 76.57%±3.29%,79.60%±0.92%,and 77.00%±0.71%in 29℃,33℃and 37℃treatment groups,respectively,significantly decreased than those of the control(84.50%±1.57%).Exposure of E.sinensis to 29℃,the content of total amino acid was 206.97±7.42 mg/g;the content of six main essential free amino acids(Thr 8.23±0.32 mg/g,Met 3.98±0.49 mg/g,Ile 8.27±0.35 mg/g,Leu 16.38±0.86 mg/g,Phe 8.34±0.40 mg/g,Lys 12.56±0.64 mg/g)was significantly higher than that of control group and 33℃and 37℃high-temperature treatment groups.Results suggested that 29℃short-time treatment can significantly increase the content of essential free amino acids in E.sinensis.In this study,the effects of high-temperature stress on the active constituents of medicinal insects were reported for the first time.The results will provide a theoretical basis for further understanding the effect of high-temperature on the medicinal value and for the cultivation conditions of ground beetle.