Adsorption of Saponin Compound in Carica papaya Leaves Extract Using Weakly Basic Ion Exchanger Resin

摘要

Adsorption of saponin compound in papaya leaves juice extract using Amberlite? IRA-67 resin was not reported in previous studies. In this research, Amberlite? IRA-67 was used to determine the amount of saponin that can be adsorbed using different weights of dry resin (0.1 g and 0.5 g). Peleg model was used to determine the maximum yield of saponin (43.67 mg) and the exhaustive time (5.7 days) prior to a preliminary resin-saponin adsorption study. After adsorption process, there was no significant difference (p>0.05) in total saponin content (mg) for sample treated with 0.1 g (3.79 ± 0.55 mg) and sample treated with 0.5 g (3.43 ± 0.51 mg) dry weight resin. Long-term kinetic adsorption of resin-saponin method (>24 hours) should be conducted to obtain optimum freed saponin extract. Besides that, sample treated with 0.1 g dry weight resin had high free radical scavenging value of 50.33 ± 2.74% compared to sample treated with 0.5 g dry weight resin that had low free radical scavenging value of 24.54 ± 1.66% dry weights. Total saponin content (mg), total phenolic content (mg GAE) and free radical scavenging activity (%) was investigated to determine the interaction of those compounds with Amberlite? IRA-67. The RP-HPLC analysis using ursolic acid as standard at 203 nm showed no peak even though ursolic acid was one of the saponin components that was ubiquitous in plant kingdom. The absence of peak was due to weak solubility of ursolic acid in water and since it was only soluble in solvent with moderate polarity. The Pearson's correlation coefficient for total saponin content (mg) versus total phenolic content (mg GAE) and radical scavenging activity (%) were +0.959 and +0.807. Positive values showed that whenever there was an increase in saponin content (mg), the phenolic content (mg GAE) and radical scavenging activity (%) would also increase. However, as the resin-saponin adsorption was carried out, there was a significant decrease of radical scavenging activity (%) as the amount of the resin increased. Moreover, the saponin amount did not show any reduction as the amount of resin resin increased. Therefore, there was other active ingredient which has the antioxidant properties were affected by the adsoprtion process. For that reason, the kinetic equilibrium of resin-saponin adsorption studies against the ratio of resin-to-extract has to be carried out to determine the efficacy of the extract therapeutic properties prior to the cell culture studies.