Red cell haemolysis test as an in vitro approach for the assessment of toxicity of karanja oil

Abstract

The karanja tree grows in parts of India and Australia. The oil from seed kernels was found to be toxic to animals. The annual potential availability of the oil is around 135,000 tons in India. In order to use it for beneficial purposes, it is necessary to detoxify the oil. In the present study, the oil was assessed for toxicity by the red cell haemolysis test and estimating the LDH in the supernatant. The non-lipid constituents were isolated from raw oil by aqueous methanol extraction. The raw oil and the non-lipid fraction were found to haemolyse the red cells with release of LDH, whereas the extracted oil did not show such a manifestation. There was a good correlation between haemolytic activity and LDH released from cells. These findings were further confirmed with in vivo studies where the raw and extracted karanja oils showed 100% and nil mortality in rats dosed orally at 10 and 20 ml/kg body weight, respectively. This haemolysis test can be used as an in vitro method to predict toxicity and to monitor the detoxification of the oils prior to use in in vivo studies for toxicological evaluation. The fatty acid composition of the raw and extracted karanja oils showed no difference.