ISSN:
1745-4514
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Process Engineering, Biotechnology, Nutrition Technology
Notes:
A proteinaceous alpha-amylase inhibitor from the cormel of taro (Colocasia esculenta) was purified by extraction, heat treatment, ammonium sulfate precipitation, and column chromatography on Sephadex G-100, BioGel P-30, and DE-53 cellulose. This protein (aptly named esculentamin) was shown to be an acidic (pI = 4.4) glycoprotein with a carbohydrate content of 3.64% and a molecular weight of 11,800 daltons. Esculentamin activity was essentially stable to boiling for 3 h (pH 7.0), to a pH range of 2.0 to 12.0 (at 4°C), and to 6 M guanidine hydrochloride and 8 M Urea. Amino acid analysis indicated a predominance of acidic over basic amino acids, while side-by-side neutral and alkaline absorption spectra strongly suggested a lack of tryptophan. “Bifunctional” inhibitory activity towards both α-amylase and proteases was not observed with esculentamin (i. e., it did not inhibit the several proteases tested, viz. trypsin and subtilisin).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1745-4514.1990.tb00834.x
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