New dammarane triterpenoid saponins from the leaves of Cyclocarya paliurus
Abstract Three new dammarane triterpenoid saponins, cyclocariosides O-Q (1–3), were isolated from the ethanolic extracts of the leaves of Cyclocarya paliurus. The structures of these compounds were elucidated by spectroscopic methods.
Seco-dammarane triterpenoids from the leaves of Cyclocarya paliurus.
The leaves of Cyclocarya paliurus with sweet taste are often used as herbal tea in People's Republic of China. In this study eight previously undescribed seco-dammarane type triterpenoids, cyclocariols A-H along with seven known compounds were isolated and characterized from its leaves. A possible biogenetic pathway for seco-dammarane type triterpenoids formation has been discussed. Cyclocariols A-H were evaluated for their cytotoxicities against human liver (SMMC-7721) and breast cancer (BT-549) cell lines. Cyclocariols A, B, E, and H were also tested against human colon tumor (HCT-116) cell lines, where all four exhibited good activities with IC50 values of 6.53, 4.94, 8.24, and 6.48 μM, respectively.
Structural features of immunostimulatory polysaccharide purified from pectinase hydrolysate of barley leaf.
Four polysaccharide fractions were isolated from young barley leaves treated with or without pectinase followed by ethanol fractionation. Among the polysaccharide fractions, BLE-P isolated from pectinase digested with a high molecular weight had the most enhanced macrophage stimulatory activity, indicating that pectinase digestion of barley leaf is a useful method for enhancement of its activity. BLE-P was further purified by column chromatography to identify the chemical and structural properties. BLE-P-I eluted in void volume fraction showed potent macrophage stimulatory activity. Monosaccharide composition and linkage analysis indicated that at least three kinds of polysaccharide, that is, glucuronoarabinoxylan (GAX; 40-45%), rhamnogalacturonan-I (RG-I) with branching mainly involving a type II arabinogalactan (AG-II) side chain (30-35%), and linear glucan such as starch and cellulose (less than 10%) coexisted in BLE-P-I. Given the association with macrophage stimulatory activity, it is likely that the GAX and to the RG-I polysaccharide branched with an AG-II side chain may be important for expression of the activity in barley leaf.