Fitoterapia 79 (2008) 456 – 457 www.elsevier.com/locate/fitote
α-Glucosidase inhibitor from Chinese aloes Nilubon Jong-Anurakkun ⁎, Megh Raj Bhandari, Gao Hong, Jun Kawabata Laboratory of Food Biochemistry, Division of Applied Bioscience,Graduate School of Agriculture, Hokkaido University, Sapporo 060-8589, Japan Received 18 June 2007; accepted 11 February 2008 Available online 27 May 2008
Abstract Activity-guided fractionation of the methanol extract of Chinese aloes led to the isolation of aloeresin A, which demonstrated significant dose dependent α-glucosidase inhibitory activities, with IC50 values of 11.94 and 2.16 mM, against rat intestinal sucrase and maltase, respectively. © 2008 Elsevier B.V. All rights reserved. Keywords: Chinese aloes; Aloeresin A; α-Glucosidase inhibitor
1. Plant Aloes is the dried brownish mass of the drained liquid from the cut leaves of various species of Aloe . Chinese aloes sample was purchased from Chinese drug store in Sapporo, Japan. 2. Uses in traditional medicine Aloes has long been used as a traditional remedy for diabetes in Arabian peninsula [2,3]. 3. Previously isolated compounds No reports for Chinese aloes. 4. New isolated compound Aloeresin A. 5. Studied activity α-Glucosidase (sucrase, maltase) inhibitory activities evaluated using the methods described previously [4–6]. ⁎ Corresponding author. Tel./fax: +81 11 706 2496. E-mail address: [email protected]
(N. Jong-Anurakkun). 0367-326X/$ - see front matter © 2008 Elsevier B.V. All rights reserved. doi:10.1016/j.fitote.2008.02.010
N. Jong-Anurakkun et al. / Fitoterapia 79 (2008) 456–457
Fig. 1. Chemical structure of aloeresin A.
6. Tested material Aloeresin A. 7. Results and conclusions Aloeresin A, which has been known as a constituent of Aloe ferox , exhibited significant dose dependent inhibitory activity against rat intestinal sucrase and maltase with IC50 values of 11.94 and 2.16 mM, respectively. Previous research  reported the effect of aloes on blood glucose levels in alloxan diabetic mice and gave the assumption that the hypoglycemic effect of aloes and its bitter principle may be mediated through stimulating synthesis and/or release of insulin from the β-cells of Langerhans. However, the compound responsible for hypoglycemic activity of aloes has not been established yet. In this study we reported the aloeresin A from Chinese aloes and its inhibitory activity against rat intestinal α-glucosidase that could be responsible for the ability of aloes to reduce blood glucose level in diabetes patients (Fig. 1). Acknowledgements The authors are indebted to Mr. K. Watanabe and Dr. E. Fukushi, GC–MS and NMR Laboratory, Faculty of Agriculture, Hokkaido University, for their skillful measurements of mass spectra. References       
Denston TC. Pharmacognosy. London: Sir Isaac Pitman et Sons Ltd.; 1950. Ajabnoor MA. J Ethnopharmacol 1990;28:215. Dey L, Attele AS, Yuan CS. Altern Med Rev 2002;7:45. Nishioka T, Kawabata J, Aoyama Y. J Nat Prod 1998;61:1413. Toda M, Kawabata J, Kasai T. Biosci Biotechnol Biochem 2000;64:294. Jong-Anurakkun N, Bhandari MR, Kawabata J. Food Chem 2007;103:1319. Gramatica P, Monti D, Speranza G, Manitto P. Tetrahedron Lett 1982;23:2423.