Determination of effect of TSCE-W on cytotoxicity of CCD-1064Sk cells—The assay was determined using MTT assay, based on the reduction of a tetrazolium salt to the blue or purple coloured formazan salt in presence of mitochondrial succinate dehydrogenase in living cells24. The cells were seeded at a density of 1 × 105 cells/mL in a 96-well plate for
24 h. The medium was replaced with TSCE-W at various concentrations in 0.25% DMSO for 24 h. The cells were washed twice with 100 of PBS. The volume of 100 of MTT solution (0.4 mg/mL in incomplete medium) was added and further incubated for 4 h. The MTT solution was replaced with 100 DMSO for 15 min to dissolve the purple formazan salt. An absorbance of purple colour was measured at 570 nm using a microplate reader. The percentage of
cell viability was calculated by the equation: