Miocene Dipteronia (Sapindaceae) samaras from South Korea and their biogeographical implications.

Dipteronia, now endemic to East Asia, was widely distributed in North America during the Paleogene; however, its fossil records in Asia are scarce and none are of the Neogene. Here, we report the first Neogene Dipteronia samaras from South Korea. The more complete fossil records suggest that Dipteronia possibly originated in either Asia or North America and that its two known lineages have different geographical histories. The Dipteronia sinensis lineage was established in Asia and North America in the Paleocene and reached its maximum range in the Eocene, followed by stepwise range contraction and extirpation in North America, South Korea, and southwestern China, finally becoming endemic to central China. In contrast, the Dipteronia dyeriana lineage might have been restricted to southwestern China, where it originated, indicating historical confinement. The current restricted distribution of Dipteronia possibly resulted from its evolutionary deceleration in a constantly changing environment.

Parisfargosides A-E, five new cholestane glycosides from the rhizomes of Paris fargesii.

Five new cholestane glycosides, named parisfargosides A-E (1-5), were isolated from the rhizomes of Paris fargesii. Their structures were elucidated on the basis of UV, HR-ESI-MS, 1D and 2D NMR data as well as chemical methods. The structures of all compounds contained α, ß-unsaturated ketone unit. Compounds 3-5 possessed a 16,23-cyclocholest skeleton with 6/6/6/5/5 condensed ring, and the absolute configurations of C-16 and C-23 were confirmed according to ROESY spectra with pyridine­d5 and DMSO­d6 as solvents. In addition, the platelet aggregation activity and cytotoxic activity against five human cancer cell lines (HL-60, A549, SMMC-7721, MDA-MB-231, and SW480) of compounds 1-5 were evaluated.

Parisvaniosides A-E, five new steroidal saponins from Paris vaniotii.

The species of Paris genus is a prolific source of structurally diverse steroidal saponins responsible for multivarious biological properties. The first phytochemical investigation on the steroidal saponin constituents from the rhizomes of Paris vaniotii Lévl. led to the discovery and structural characterization of four new spirostanol saponins, named parisvaniosides A-D (1-4), and one new furostanol glycoside, named parisvanioside E (5), along with eleven known analogues (6-16). Their structures were unambiguously established on the basis of extensive spectroscopic analysis and comparison with the reported spectroscopic data. Compound 1 is a rare spirostanol saponin sharing with a C-9/C-11 double bond and a peroxy group located between C-5 and C-8 of the aglycone, whereas 3 and 4 are unusual C-27 steroidal sapoins with hydroxyl/methoxyl at both C-5 and C-6. Furthermore, 5 is the first furostanol saponin with a unique aglycone featuring two trisubstituted double bonds in ring B. All isolated saponins were evaluated for their anti-inflammatory effects on a lipopolysaccharide (LPS)-stimulated nitric oxide (NO) production model in RAW 264.7 macrophages.

Molecular networking uncovers steroidal saponins of Paris tengchongensis.

Based on a method combining the LC-MS/MS molecular networking strategy with the conventional means of phytochemical research, the chemical constituents and the availability of Paris tengchongensis, a new species found in 2017 from Yunnan Province, were investigated for the first time. The molecular networking showed that this species contained the characteristic steroidal glycosides of the genus Paris by comparison of those of Paris polyphylla var. yunnanensis. Furthermore, the detailed investigation on the 80% EtOH extract of its rhizomes resulted to the isolation of twenty steroidal glycosides including three new spirostane-type saponins, named paristengosides A-C (1-3). Their structures were confirmed by spectroscopic analyses (HRMS and NMR) and chemical methods. The new isolates were evaluated for their cytotoxicities against two human cancer cell lines (HEL and MDA-MB-231), anti-inflammatory effects on a lipopolysaccharide (LPS)-stimulated NO production model in RAW264.7 macrophages, anti-AChE, and antimicrobial activities. The results from the molecular networking and the investigation on the chemical constituents suggested that P. tengchongensis can be used as a potential resource of Rhizoma Paridis.

Genome-wide analysis of Cushion willow provides insights into alpine plant divergence in a biodiversity hotspot.

The Hengduan Mountains (HDM) biodiversity hotspot exhibits exceptional alpine plant diversity. Here, we investigate factors driving intraspecific divergence within a HDM alpine species Salix brachista (Cushion willow), a common component of subnival assemblages. We produce a high-quality genome assembly for this species and characterize its genetic diversity, population structure and pattern of evolution by resequencing individuals collected across its distribution. We detect population divergence that has been shaped by a landscape of isolated sky island-like habitats displaying strong environmental heterogeneity across elevational gradients, combined with population size fluctuations that have occurred since approximately the late Miocene. These factors are likely important drivers of intraspecific divergence within Cushion willow and possibly other alpine plants with a similar distribution. Since intraspecific divergence is often the first step toward speciation, the same factors can be important contributors to the high alpine species diversity in the HDM.

Spirostanol saponins from Ypsilandra parviflora induce platelet aggregation.

Phytochemical investigation on the whole plants of Ypsilandra parviflora led to the isolation of seven new spirostanol saponins, named ypsiparosides A-G, together with 14 known saponins. Their structures were unambiguously established based on extensive spectroscopic evidence and chemical methods. The induced rabbit platelet aggregation activities of the isolates were tested. Compounds 4, 15, and 17 showed maximal platelet aggregation rates ranging from 43 to 55% at a concentration of 300µg/mL. Further experiments exhibited that compounds 4, 15, and 17 possessed EC50 values of 642.9, 95.3, and 300.8µg/mL, respectively.

Cytotoxic steroidal saponins from Trillium kamtschaticum.

Eight new steroidal saponins, trillikamtosides K-R (1-8), along with three known analogues, were isolated from the whole plants of Trillium kamtschaticum. Their structures were unambiguously established by interpretation of spectroscopic data (MS and NMR) and chemical methods. Compound 1 had a rare aglycone featuring a skeleton of 16-oxaandrost-5-en-3-ol-17-one, which was reported for the first time. The isolated saponins were tested for cytotoxicities against HCT116 cells, and trillikamtoside R (8) was found to show the most cytotoxic effect with an IC50 value of 4.92µM.