Alkaloidal glycosidase inhibitors and digestive glycosidase inhibition in specialist and generalist herbivores of Omphalea diandra
Alkaloidal glycosidase inhibitors and digestive glycosidase inhibition in specialist and generalist herbivores of Omphalea diandra
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DOI：
10.1023/b:joec.0000006349.84075.f0
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发表时间：
1997-01-01
影响因子：
2.3
通讯作者：
Smith, NG
中科院分区：
文献类型：
--
作者：
Kite, GC;Scofield, AM;Smith, NG
通才的食草动物的新热带藤本植物Omnalea diandra（Euphorbiaceae）的专业食草动物，幼虫的uraniid蛾Urania fulgens，就其积累的能力，由植物产生的糖苷酶抑制剂（AGIs）和其消化的糖苷酶抑制这些AGIs的阻力。多面手食草动物对AGI苷元2 R，5 R-二羟甲基-3R，4 R-二羟基吡咯烷（DMDP）和2，6-二脱氧-2，6-亚氨基-D-甘油基-L-古洛庚糖醇（HNJ）的积累量低于乌骨鸡幼虫。fulgens，其含有0.05-0.11%干重的DMDP和0.17-0.35%的HNJ。以O. diandra要么缺席的通才和专业食草动物或目前在低水平（小于0.01%），即使HNJ-葡萄糖苷往往是最丰富的AGI在树叶。对食草动物粪便的分析表明，未能积累AGIs是由于化合物被代谢而不是排泄。U.与通性食草动物相比，荧光虫幼虫对AGI苷元的抑制作用更有抵抗力。同样，蔗糖和麦芽糖水解的两个通才鳞翅目草食动物，幼虫的Panthiades ballus和Theope virgilius，是更耐抑制DMDP比Spodopreta littoralis，鳞翅目幼虫，不遇到O。自然界中的Diandra在对糖苷酶AGI的敏感性方面，来自多功能鞘翅目Rhabdopterus fulvipes的差异很小。diandra，与鞘翅目Dermestes maculatus相比，它没有。发现HNJ的葡萄糖苷是所有被检查的昆虫的海藻糖酶活性的非常明显的抑制剂。AGIs被认为会降低O. diandra不适应食草动物，而不是急性毒性。尽管如此，美国。fulgens似乎是唯一的Omnalea喂养昆虫的能力，积累AGI，这表明它获得了一些优势，从存储这些化合物。
Generalist herbivores of the neotropical liana Omphalea diandra (Euphorbiaceae) were compared to the specialist herbivore, larvae of the uraniid moth Urania fulgens, with respect to their ability to accumulate the alkaloidal glycosidase inhibitors (AGIs) produced by the plant and the resistance of their digestive glycosidases to inhibition by these AGIs. The generalist herbivores did not accumulate the AGI aglycones 2R,5R-dihydroxymethyl-3R,4R-dihydroxypyrrolidine (DMDP) and 2,6-dideoxy-2,6-imino-D-glycero-L-gulo-heptitol (HNJ) to the levels detected in larvae of U. fulgens, which contained 0.05-0.11% dry weight DMDP and 0.17-0.35% HNJ. Glucosides of DMDP and HNJ that were synthesized by O. diandra were either absent from both the generalist and the specialist herbivores or present at low levels (less than 0.01%), even though HNJ-glucoside was often the most abundant AGI in the foliage. Analyses of the herbivores' feces indicated that failure to accumulate AGIs was due to the compounds being metabolized rather than excreted. The digestive glycosidases of U. fulgens larvae were more resistant to inhibition by AGI aglycones than those of the generalist herbivores. Similarly, sucrose and maltose hydrolysis in two of the generalist lepidopteran herbivores, larvae of Panthiades ballus and Theope virgilius, was more resistant to inhibition by DMDP than in larvae of Spodopreta littoralis, a lepidopteran which does not encounter O. diandra in nature. There was little difference in the susceptibility to AGIs of glycosidases from the generalist coleopteran Rhabdopterus fulvipes, which naturally feeds on O. diandra, compared with the coleopteran Dermestes maculatus, which does not. The glucoside of HNJ was found to be a very patent inhibitor of trehalase activity in all the insects examined. AGIs are considered to reduce the nutritional value of O. diandra to nonadapted herbivores rather than be acutely toxic. Nevertheless, U. fulgens does appear to be unique among Omphalea-feeding insects in its ability to accumulate AGIs, suggesting that it gains some advantage from storing these compounds.