ISSN 2169-3048
International Journal of Biochemistry and Biotechnology Vol. 1 (3), pp. 137-145, May, 2012. © International Scholars Journals
Full Length Research Paper
Effects of lipid extracts from nigella sativa seeds on the reduction of ATP and the inhibition of alpha glucosidase activity
Widad Sobhia, Bachra Khettalb, Djebbar Atmania,B, Caroline Stevignyc, Marie- Jeanne Mukazayirec, Pedro Buc CALDERON D, Pierre Duezc and Mustapha Benboubetraa*
a Laboratory of Applied Biochemistry, Faculty of Sciences, University of Setif, Algeria.
b Department of Physical and Chemical Biology, Faculty of Life and Nature Sciences, University of Bejaia; Algeria.
c Laboratory of Pharmacognosy, Bromatology and Human Nutrition, Institute of Pharmacy, Université Libre de Bruxelles (ULB), Belgium.
d Pharmacocinétic Unit, Metabolism, Nutrition and Toxicology, Faculty of Medicine, Catholic University of Louvain, Bruxelles, Belgium.
*Corresponding Author’s E-mail: benboubetra@yahoo.co.uk
Received March 12, 2012; Accepted May 18, 2012
Abstract
Extracts from the seeds of Nigella sativa have been traditionally used to treat inflammations, liver disorders and arthritis. Experimentally, it has been demonstrated they possess antioxidant and hepatoprotective properties. Beside the hypoglycaemic and hypolipidic effects, this study was carried out to evaluate, in vitro, toxicological effect of lipid extracts from the Nigella sativa seeds. The tested fractions were: (i) defatted methanolic extract, (ii) total lipid extract obtained by hexane extraction from methanolic extract and (iii) neutral and polar lipid fractions. Toxicological evaluation was carried out on precision-cut rat liver slices (PCLS). The fractions were assessed, in vitro, for their inhibitory potential on the activity of alpha-glucosidase as suppressing the enzyme activity it is one of the therapeutic approaches for decreasing postprandial hyperglycaemia.On PCLS, lipid extracts reduced ATP levels by 27-35 %. High inhibition of alpha-glucosidase by the two polar lipid fractions (F6 and F7) was reflected by their IC50 (0.51 ± 0.04 mg/ml and 0.55 ± 0.09 mg/ml, respectively), compared to acarbose (0.53 ± 0.06 mg/ml) and thymoquinone (0.65 ± 0.05 mg/ml). The inhibitory effect on alpha-glucosidase activity could be a result of an inhibition of the early steps of carbohydrate metabolism and hence are good candidates for the anti-hyperglycaemic effect of this medicinal plant.
Keywords: Alpha-glucosidase, Hepatotoxicity, Induced-Diabetes, Nigella sativa, Polar lipids.