The current study found that the optimal conditions
to extract saponins using water and the traditional
brewing method were: 85 °C, 25 min and a water-toleaf
ratio of 20:1 mL g
1. However, 80% (v/v) ethanol
proved to be more effective than water in extracting
saponins from papaya leaf. Both water and ethanol
saponin-enriched extracts possessed similar antioxidant,
free radical scavenging and ion-reducing capacity
at concentrations ranging from 25 to 100 lg mL
1.
The ethanol extract was found to have a slightly
higher antioxidant capacity than the water extract at a
concentration of 200 lg mL
1. Ethanol extracts were
more effective in inhibiting the proliferation of two
pancreatic cancer cell lines and were at least as effective
as the chemotherapeutic agent gemcitabine. Therefore,
saponins in papaya leaf are bioactive compounds
that exhibit potential in limiting the proliferation of
certain pancreatic cancer cell lines. Studies aimed at
characterising the bioactivity of individual saponins
isolated from papaya leaf are currently underway.