Preparation of Karkataka Taila, an Edible crab Rasayana, and assessment of its toxicological effects on SH-SY5Y cell line and on Drosophila melanogaster embryos

Background: Karkataka Taila (KT) is a virgin coconut oil (VCO) based Rasayana formulation that is enriched with the flesh of freshwater edible crab, Scylla serrata, used to treat Parkinson’s Disease (PD) or Kampavata by local Ayurveda practitioners of Kerala state. There is no scientific study carried out on its toxicological effects so far. Objective: To understand the ayurvedic preparation method for KT and assessment of the toxicological effects of the KT and VCO on SH-SY5Y cell lines and Drosophila melanogaster embryos. Materials and methods: The SH-SY5Y cell lines treated with different concentrations of KT and VCO range from 6.25 μg/ml to 100 μg/ml and Drosophila melanogaster embryos fed with food containing different concentrations of KT and VCO, ranging from 0.005 % to 10 %. Results: KT and VCO did not show any significant cytotoxicity effect on SH-SY5Y cell lines up to a dose concentration of 25 μg. But, at 50 μg and 100 μg concentrations, KT has shown a cytotoxic effect and it was higher than the VCO. The toxicological analysis in Drosophila has shown that the survival rate of the KT treated group at concentration ranges from 0.005 % to 10 % is significantly decreased from 78.8 % to 27.7 %, compared to the control group, whereas in VCO treated group, at 0.005 % to 10 %, the survival rate has decreased from 76.2 % to 66 %, which is marginally higher than the KT treated group. Conclusion: Our findings revealed that as the concentration of Rasayana in the medium increases, there is a noticeable adverse effect on the percentage viability in SH-SY5Y cell lines and in the number of offspring in Drosophila. The effect of vehicle, VCO, at the same concentration has shown a protective effect on cell lines and flies. It can be concluded that the toxic effect has been observed only at higher concentrations of KT and at the lower concentration, the toxic effect has been minimal.