Abstract

Crude oil (CO) is a substance trado-medically used within some rural population as an antidote to poisoning and a cure for various gastro-intestinal disturbances among others. The ingestion of crude oil either orally or through polluted marine species represents a pathway for the delivery of potential toxicants to the human system. The study, therefore, analysed the effects of bonny light crude oil on the activities of anti-oxidative enzymes [superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST)] and the concentration of total proteins (TP). The results show that SOD activity was significantly lower (p<0.05) in the control rats (0.97±0.01) compared to the rats administered 6 ml of crude oil/kg body weight (b.w) (1.31 ± 0.17), and 9 ml of crude oil/kg b.w (1.27 ± 0.03). There was however, no significant difference (p>0.05) between the SOD activity of the rats treated with 3 ml of crude oil/kg b.w (1.25 ± 0.27) and that of the control rats. CAT specific activity in the rats of the control group (5.5 ± 3.2x10^-3) was lower than that of the rats administered 3 ml of crude oil/kg b.w (6.2±3.4 x 10^-3), 6 ml of crude oil/kg b.w (7.5±4.8 x 10^-3) and 9 ml of crude oil/kg b.w (12.5 ± 8.3 x 10^-3); although the mean differences were not statistically significant (p>0.05). GST specific activity was higher in the rats of the crude oil-untreated group (88.6 ± 136.3 x 10^-3) compared to the rats of the group treated with 3 ml of crude oil/kg b.w (82.7 ± 32.3 x 10^-3), 6 ml of crude oil/kg b.w (26.0 ± 19.5 x 10^-3) and 9 ml of crude oil/kg b.w (25.4 ± 21.2 x 10^-3). Nevertheless, the mean differences were still not statistically significant (p>0.05). Total proteins concentration was significantly lower (p<0.05) in the rats given 9 ml of crude oil/kg b.w (0.33±0.08) compared to that of the control rats (0.05±0.02). In connection with the above results, the crude oil at high dose was found to have oxidative stress-inducing potential and hence, warrants that its use be discouraged or replaced with other less or non-toxic agents with similar therapeutic values as it.

Key words: Crude oil, trado-medically, bonny light, anti-oxidative enzymes and total proteins