Converting ginsenosides from stems and leaves of Panax notoginseng by microwave processing and improving their anticoagulant and anticancer activities

A microwave processing technology was applied to degrade saponins from the stems and leaves of Panax notoginseng. Six transformation products (1–6), named 20(S)-ginsenoside Rg3 (1), 20(R)-ginsenoside Rg3 (2), notoginsenoside SFt3 (3), ginsenoside Rk1 (4), ginsenoside Rg5 (5), and 20(S)-ginsenoside Rh2 (6) were isolated and identified from a microwave processed extract of the stems and leaves of P. notoginseng (MEL). This transformation method was also applied for producing the minor ginsenosides in flowers, seeds and pedicels of P. notoginseng. The extract and compounds 1–6 in MEL were evaluated in vitro for anticancer and anticoagulant activities. The results showed that the MEL extract and transformation products had outstanding inhibitory activities against human cervical cancer Hela and lung cancer A549 cells. The strongest inhibitory effect was observed for 20(S)-Rh2 (6) with an IC50 value of 8.23 μM in Hela cells. Moreover, the results showed that the MEL significantly prolonged prothrombin time in a concentration-dependent manner. The anticoagulant effect of the MEL improved with the increased contents of Rk1, Rg5, and SFt3.