Inhibition of Proliferation of HeLa Cells by Pulsed Electric Field Treated Mentha piperita (Mint) Extract

In this research, the effectiveness of Mentha piperita (M. piperita) leaf extract against HeLa, a human cervical cancer cell line was investigated. We assessed the phytochemicals present in this extract by phytochemical screening tests and analysed the free radical scavenging activity and anticarcinogenic activity using without Pulsed Electric Field (PEF). The methanolic M. piperita extract was prepared by the Soxhlet extraction method, and was treated by PEF using 50 unipolar pulses, 10 kV/cm, 100 mu s and the effect of PEF on the antioxidant and anticarcinogenic activities of M. piperita extract was investigated and compared to Soxhlet extraction (70 degrees C for 8 h). The preliminary phytochemical analysis indicated the presence of phenols, tannins, flavonoids, alkaloids, steroids, reducing sugars and the absence of saponins, anthocyanins, catechins, terpenoids, carotenoids, and anthraquinones. The free radical scavenging activity of both PEF treated and untreated extract was determined by 2,2-Diphenyl-1-Picrylhydrazyl assay. Compared to untreated extract, 7.36% greater antioxidant activity was obtained from PEF treatment. The anticarcinogenic activity of both extracts were determined by MTT proliferation assay against Hela cells. The results indicated a viability of 34.77% for the PEF treated M. piperita extract (compared to 41.2% for the Soxhlet extract and 100% for the control). This indicates that the PEF-treated M. piperita extract showed higher antioxidant activity and anticarcinogenic activity than the other extracts. Hence, the application of PEF may be appropriate to achieve antioxidant rich extract and maximal cell death could be achieved with PEF treatment thereby, reducing the concentration of extract required for treating cancer.