Bonavides Krishna B, Pelegrini Patrícia B, Laumann Raúl A, Grossi-de-Sá Maria F, Bloch Carlos, Melo Jorge A T, Quirino Betania F, Noronha Eliane F, Franco Octávio L
Centro de Análises Proteomicas e Bioquimicas, Universidade Católica de Brasília, Brasília, Distrito Federal, Brazil.
J Biochem Mol Biol. 2007 Jul 31;40(4):494-500. doi: 10.5483/bmbrep.2007.40.4.494.
The endophytic bruchid pest Callosobruchus maculatus causes severe damage to storage cowpea seeds, leading to economical losses. For this reason the use of alpha-amylase inhibitors to interfere with the pest digestion process has been an interesting alternative to control bruchids. With this aim, alpha-amylase inhibitors from baru seeds (Dipteryx alata) were isolated by affinity chromatographic procedures, causing enhanced inhibition of C. maculatus and Anthonomus grandis alpha-amylases. To attempt further purification, this fraction was applied onto a reversed-phase HPLC column, generating four peaks with remarkable inhibition toward C. maculatus alpha-amylases. SDS-PAGE and MALDI-ToF analysis identified major proteins of approximately 5.0, 11.0, 20.0 and 55 kDa that showed alpha-amylase inhibition. Results of in vivo bioassays using artificial seeds containing 1.0% (w/w) of baru crude extract revealed 40% cowpea weevil larvae mortality. These results provide evidence that several alpha-amylase inhibitors classes, with biotechnological potential, can be isolated from a single plant species.
内寄生豆象害虫四纹豆象对豇豆贮藏种子造成严重损害，导致经济损失。因此，使用α-淀粉酶抑制剂干扰害虫消化过程已成为控制豆象的一种有趣替代方法。出于这个目的，通过亲和色谱法从香豆种子（Dipteryx alata）中分离出α-淀粉酶抑制剂，对四纹豆象和棉铃象甲的α-淀粉酶产生了增强的抑制作用。为了进一步纯化，将该级分应用于反相HPLC柱上，产生了四个对四纹豆象α-淀粉酶具有显著抑制作用的峰。SDS-PAGE和MALDI-ToF分析鉴定出约5.0、11.即20.0和55 kDa的主要蛋白质，它们具有α-淀粉酶抑制作用。使用含有1.0%（w/w）香豆粗提物的人工种子进行的体内生物测定结果显示，豇豆象甲幼虫死亡率为40%。这些结果证明，可以从单一植物物种中分离出具有生物技术潜力的几类α-淀粉酶抑制剂。
