Evaluation of the cytotoxic activity of crocin and safranal using potato disc and brine shrimp assays

In this study, two constituents of saffron stigma (crocin and safranal) were tested for possible cytotoxic and antitumoral activity using brine shrimp and potato disc assays. In the brine shrimp assay, three wells containing 10 nauplii were tested for each concentration. After 24h, the number of the nauplii was counted. To investigate the antimicrobial activity of safranal and crocin against Agrobactrium tumefaciens, the MIC of these compounds were evaluated using microplate and spectrophotometry method. In the potato disc assay, discs of potato were cut with specific diameter and transferred on 1.5 % agar under laminar air cabinet. Discs were incubated with 50 μl of a mixture containing suspension of Agrobactrium tumefaciens (108 cfu/ml) and 50 μl of a solution of safranal (0.075, 0.150, 0.300, 0.450, 0.600 and 0.800 mg/ml) or crocin (0.5, 1.0, 1.5, 3.0, 6.0 and 8.0 mg/ml) (1:1) in 25 °C for 20 days until the tumors were counted. The MIC of safranal and crocin were 1 and 10 mg/ml. The LC50 values of safranal and crocin against brine shrimp were 14.342 and 147.036 ppm. The percent of tumor growth inhibition of safranal at 0.075-0.800 mg/ml and crocin at 0.5-0.8 mg/ml were 5.6-90.2 % and 5.2-88.8 %, respectively and the EC50 Values of safranal and crocin against tumors were 0.31 and 2.34 mg/ml, respectively. Both safranal and Crocin have remarkable toxic effect and suitable dose dependent antitumoral activity. Between the two compounds, safranal has higher toxic effect and antitumoral activity compared to crocin.