Effects of Alium cepa Linn on rhodanese activities and half-life of cyanide in the blood

Abstract

Rhodanese is the major detoxifying enzyme for cyanide and requires sulphur for its action. Allium cepa (Onion) is rich in organosulphur which may serve as an antidote for cyanide poisoning by supplying sulphur to the enzyme rhodanese. The possible effects of Allium cepa on rhodanese activity during cyanide toxicity was investigated in male Wistar rats. Sixty Wistar rats (150-180 g) were divided into ten groups of six rats each. The first six groups were used for in vivo rhodanese activities evaluation after treatments orally with either KCN (7 mg/kg bwt/day KCN), KCN+ 300 mg Methanol Extract of Allium cepa (MEAC)/kg bwt/day, KCN+ 600 mg MEAC/kg bwt/day, KCN+ 600 mg sodium thiosulphate (Na2S2O3)/kg bwt/day or 600 mg MEAC/kg bwt/day respectively. The last four groups were used for the evaluation of half-life of KCN after treatment orally with distilled water (control), 600 mg MEAC/kg bwt/day, 600 mg Na2S2O3/kg bwt/day and raw onion adlibitum respectively for two weeks before intravenous injection of KCN. In vitro rhodanese activity was determined using liver homogenate. Results of the in vivo study showed liver rhodanese activity was significantly higher (p< 0.05) in the cyanide only group and in the cyanide+ Na2S2O3 group when compared with the control group, but administration of MEAC in the cyanide treated group did not enhance the activities of rhodanese. The results of the in vitro study showed that rhodanese activity was more enhanced in the presence of essential oil of onion and Na