Optimization of Subcritical Fluid Extraction for Total Saponins from Hedera nepalensis Leaves Using Response Surface Methodology and Evaluation of Its Potential Antimicrobial Activity

Abstract

(1) Background: Hedera nepalensis (Araliaceae) is a recognized medicinal plant founded in Asia that has been reported to work in antioxidant, antifungal, antimicrobial, and antitumor capacities. (2) Methods: The subcritical fluid extraction of saponin from Hedera nepalensis leaves and the optimum of the extraction process based on yield of saponin contents (by calculating the hederacoside C contents in dried Hedera nepalensis leaves) are examined by response surface methodology (RSM). Furthermore, the antimicrobial activity of the extract is tested for potential drug applications in the future. (3) Results: Based upon RSM data, the following parameters are optimal: extraction time of 3 min, extraction temperature of 150 °C, and a sample/solvent ratio of 1:55 g/mL. Under such circumstances, the achieved yield of saponin is 1.879%. Moreover, the extracts inhibit the growth of some bacterial strains (Streptococcus pneumoniae, Streptococcus pyogenes, Haemophilus influenza) at a moderate to strong level with inhibition zone diameter values ranging from 12.63 to 19.50 mm. (4) Conclusions: The development of such a model provides a robust experimental process for optimizing the extraction factors of saponin contents from Hedera nepalensis extract using subcritical fluid extraction and RSM. Moreover, the current work reveals that saponin extracts of Hedera nepalensis leaves exhibit a potential antimicrobial activity, which can be used as scientific evidence for further study.

Supercritical Technology Applied to Food, Pharmaceutical, and Chemical Industries

“…Duong and coworkers [44] optimized the recovery of saponins from Hedera nepalensis leaves with the use of pressurized liquid extraction. The Box-Behnken design was adopted by the authors to select the extraction time, solvent used, and temperature.…”

Structural characterization of water-soluble polysaccharides isolated from leaves of Hedera nepalensis

“…[1][2][3][4][5]. Also, Hedera nepalensis is a recognized medicinal plant that has been reported to work in antifungal, antimicrobial, antioxidant and antitumor capacities [6][7][8][9][10].…”

“…Many researchers have paid attention to the phytochemicals obtained from Hedera nepalensis in the relation to their isolation, purification, and characterization [1][2][3][4][5][6][7][8][9][10][11]. Kizu et al isolated various chemical compounds consisting of a complex mixture of saponins from Hedera nepalensis for the first time [11].…”

“…Jafri et al reported this plant contains plenty of phenol chemical compounds, which show significant antioxidant potential [9]. Duong et al mentioned a model, which provides a robust experimental process for optimizing the extraction factors of saponin contents from Hedera nepalensis extract using subcritical fluid extraction and response surface methodology (RSM) [10]. Besides, the phytochemical analysis of Hedera nepalensis showed the presence of various chemical compounds such as alkaloids, glycosides, flavonoids, steroids, tannins and terpenoids [1][2][3][4][5][6][7][8][9][10][11].…”

“…Pectins are categorized as acidic polysaccharides because of their high levels of uronic acid residues, and possess various activities, including immunological regulation, anti-cancer, hypoglycemic effect, antiviral activity and anti-inflammatory effect [12][13][14][15]. However, despite extensive research on the chemical compounds derived from Hedera nepalensis and their biological activities, the study of polysaccharides from this plant has been limited [1][2][3][4][5][6][7][8][9][10][11].…”