de Lumen B O, Chan J
Adv Exp Med Biol. 1986;199:413-27. doi: 10.1007/978-1-4757-0022-0_23.
The trypsin inhibitors (TI) of winged bean (Psophocarpus tetragonolobus) isolated by affinity chromatography consisted of 8 protein bands by disc polyacrylamide electrophoresis. All the bands exhibited trypsin inhibitor activity (TIA) with two of the major bands also exhibiting chymotrypsin inhibitor activity (CIA). Electrofocusing separated the TI into 5 protein bands. Two bands with dual TIA/CIA activities had acidic pI while 3 bands with TIA only had alkaline pI. The TI belonged to two molecular weight groups of 20,900 and 16,600, as determined by NaDodSo4 polyacrylamide electrophoresis. Sufficient quantities of TI were isolated by affinity chromatography for rat feeding. Raw winged bean was toxic to rats, causing death after 12 days of feeding. Autoclaved winged bean was not toxic but caused growth inhibition. When fed with casein, the isolated inhibitor caused slight growth inhibition, pancreatic and spleen hypertrophy. It was concluded that TI in winged bean was not primarily responsible for the toxicity of raw winged bean.
采用亲和层析法从四棱豆（Psophocarpus tetragonolobus）中分离得到的胰蛋白酶抑制剂（TI），经圆盘聚丙烯酰胺电泳分析由8条蛋白带组成。所有条带均表现出胰蛋白酶抑制活性（TIA），其中两条主要条带还表现出糜蛋白酶抑制活性（CIA）。等电聚焦法将TI分离为5条蛋白带。两条具有双重TIA/CIA活性的条带具有酸性pI，而3条仅具有TIA的条带具有碱性pI。通过NaDodSo4聚丙烯酰胺电泳测定，TI属于分子量分别为20900和16600的两个分子量组。通过亲和层析法分离得到了足够量的TI用于大鼠喂养。生四棱豆对大鼠有毒，喂食12天后导致死亡。高压灭菌的四棱豆无毒，但会导致生长抑制。当与酪蛋白一起喂食时，分离得到的抑制剂会导致轻微的生长抑制、胰腺和脾脏肥大。得出的结论是，四棱豆中的TI并非生四棱豆毒性的主要原因。
