65–0.72), and separated on a silica gel column (φ 4 cm × 6 cm) with a CHCl3–MeOH–H2O (65:35:10, 98 L) as

eluent for 20 fractions (PGB16+17-1–PGB16+17-20). PGB16+17-7 (370 mg, Ve/Vt = 0.18–0.20) was fractionated over the ODS column (φ 4 cm × 5 cm, MeOH–H2O = 3:1, 2 L) for 20 fractions (PGB16+17-7-1–PGB-16+17-7-20) including ginsenoside Rf [2, PGB16+17-7-16, 3.4 mg, Ve/Vt = 0.712–0.798, TLC Rf = 0.42 (RP-18 F254S, MeOH-H2O = 3:2), and Rf = 0.44 (Kieselgel 60 F254, CHCl3–MeOH–H2O = 65:35:10)]. Fraction PCI32765 PGB16+17-9 (1.7 g, Ve/Vt = 0.25–0.29) was separated over the ODS column (φ 4 × 6 cm, MeOH–H2O = 3:1, 7 L) into 36 fractions (PGB16+17-9-1–PGB16+17-9-36) including the 20-gluco-ginsenoside Rf [4, PGB16+17-9-12, 223 mg, Ve/Vt = 0.22–0.27, TLC Rf = 0.54 (RP-18 F254S, MeOH–H2O = 2:1), Rf = 0.31 phosphatase inhibitor library (Kieselgel 60 F254, CHCl3–MeOH–H2O = 65:35:10)] and the ginsenoside Re [1, PGB16+17-9-15. 68.3 mg, Ve/Vt = 0.38–0.40, TLC Rf = 0.50 (RP-18 F254S, MeOH–H2O = 2:1), and Rf = 0.36 (Kieselgel 60 F254, CHCl3–MeOH–H2O = 65:35:10)]. Physicochemical and spectroscopy data from each ginsenoside are in Table 1, Table 2 and Table 3. The purity

of the isolated compounds was over 99% as determined by HPLC and 1H-NMR. Most of the saponins were obtained as white powders, in agreement with most of the literature in which ginsenosides were obtained as white or colorless powders [7], [10], [15] and [19]. Preliminary experiments showed that more precise and accurate melting

points were obtained with the Stanford Research Systems melting point apparatus we used than with the Fisher-John instrument used previously. As a result, melting points determined in this study often differed significantly from values found in the literature. The melting points of ginsenoside Re (1) in the literature are from 168°C to 198°C [7] and [15], whereas the results of this study indicated a melting point of 186–187°C. The literature value for ginsenoside Rf (2) is 197–198°C [15], whereas this study found that it was 180–181°C. The reference-state [15] melting point of ginsenoside Rg2 (3) www.selleck.co.jp/products/azd9291.html is 187–189°C in the literature, whereas it was found to be 191–192°C in this study. The reported melting point for 20-gluco-ginsenoside Rf (4) is 204°C [19], whereas this study found that it was 204–205°C. Significant differences from the values in the literature were also found for optical rotation. Ginsenoside Re (1) has an optical rotation of –1.0° according to previous studies [11], whereas it measured –1.80° in this study. Likewise, the optical rotation of ginsenoside Rf (2) is +6.99° in other studies [15], whereas a value of +13.80° was obtained here. The specific rotation of ginsenoside Rg2 (3) measured –3.84°, whereas the literature value is +6.0° [15]. For 20-gluco-ginsenoside Rf (4), the literature value is +21.0° [19], whereas the result obtained here was +64.00°.