In vitro reduction of trypsin inhibitor by purified NADPH/thioredoxin system from sprouts of sweet potato (Ipomoea batatas (L) Lam.) storage roots

Dong Jiann Huang, Hsien Jung Chen, Wen Chi Hou, Tzeng Err Chen, Yaw Huei Lin

研究成果: 雜誌貢獻文章同行評審

15 引文 斯高帕斯(Scopus)

摘要

Sweet potato (Ipomoea batatas (L.) Lam) storage roots were sprouted in the dark for two months, and the sprouts were used as source materials for purification of thioredoxin reductase successively via the DE-52, Sephadex G-75, and 2′,5′-ADP Sepharose 4B column chromatography. Thioredoxin reductases with a molecular mass of ca 33kDa were obtained. The purification was 813-fold and the yield was 2.5%. The effect of thioredoxin reductase on trypsin inhibitor activity (TIA) was analyzed with a TIA assay method. Native, oxidized form of trypsin inhibitors (TIs) inhibited trypsin activity to 24% of its original value. Trypsin activity recovered to 38 and 46% of its original value, respectively, when TI was reduced in advance by NTR system and DTT. The data indicate that NTR-reduced TIs lost the capacity to inhibit trypsin activity in vitro. mBBr/SDS-PAGE was used to analyze the reduction of TIs on gels. The reduced TIs were more sensitive to heat denaturation, and exhibited increased digestibility by partially purified proteases from sweet potato sprouts. Based on these results, we conclude that the NADPH/thioredoxin system is likely associated with the reduction of TIs and initiation of degradation and re-mobilization of stored TIs during sprouting of sweet potato storage roots. Meanwhile we may expect sprouts to be a better protein source for consumption than SP storage root itself.

原文英語
頁(從 - 到)435-441
頁數7
期刊Plant Science
166
發行號2
DOIs
出版狀態已發佈 - 2月 2004

ASJC Scopus subject areas

  • 植物科學
  • 生物化學
  • 生物技術

指紋

深入研究「In vitro reduction of trypsin inhibitor by purified NADPH/thioredoxin system from sprouts of sweet potato (Ipomoea batatas (L) Lam.) storage roots」主題。共同形成了獨特的指紋。

引用此