Cytotoxicological evaluation of semi-purified extracts of some dye yielding plants of the Kashmir Valley on Normal Intestinal Cell Line (IEC-6) by MTT assay

Plant extracts are widely used in many fields and there is a need to evaluate their cytotoxic effect to determine their non-cytotoxic concentration at which they can be used in a safe manner. Keeping this in view, the present study was designed to evaluate the in vitro toxicity of Celosia argentia L. var plumosa (Cockscomb), Calendula officinalis L. (Pot Marigold), Indigofera heterantha Wall. (Himalayan Indigo) and Rubia cordifolia L. (Indian Madder) on Normal Intestinal Cell Line (IEC-6) by MTT assay to test their feasibility for natural edible dye extraction. The experimental material, comprised of inflorescence of Celosia argentia L. var plumose, petals of the two varieties of Calendula officinalis L., leaves of Indigofera heterantha Wall. and leaves and roots of the Rubia cordifolia L. Cell line was exposed to 1, 4, 16, 64 and 256µg/ml concentrations of plant extracts for 24, 48, and 72hr at 37oC. Results revealed that both the varieties of Calendula officinalis L. var. Gitana Orange and Gitana Yellow did not show any cytotoxic effect on IEC-6 cell line while as Celosia argentia L. var plumose, Indigofera heterantha Wall. and Rubia cordifolia L. showed cytotoxicity. From the present study it was concluded that the extracts of the both varieties of Calendula officinalis L. var. Gitana Orange and Gitana Yellow extracts are non-toxic in nature, thus can be utilized for the extraction of natural edible dye while as the extracts of Celosia argentia L. var plumose, Indigofera heterantha Wall. and Rubia cordifolia L. had potent in vitro cytotoxic activity thus they cannot be used for extraction of natural edible food colour. However, to better evaluate the cytotoxic effect of these plant extracts, in vivo experiments on laboratory animal followed by histological analysis should be done