Hederagenin (HG) is a natural pentacyclic triterpenoid that can be isolated from various medicinal herbs. By modifying the structure of HG, multiple derivatives with superior biological activities and safety profiles have been designed and synthesized. Accumulating evidence has demonstrated that HG and its derivatives display multiple pharmacological activities against cancers, inflammatory diseases, infectious diseases, metabolic diseases, fibrotic diseases, cerebrovascular and neurodegenerative diseases, and depression. Previous studies have confirmed that HG and its derivatives combat cancer by exerting cytotoxicity, inhibiting proliferation, inducing apoptosis, modulating autophagy, and reversing chemotherapy resistance in cancer cells, and the action targets involved mainly include STAT3, Aurora B, KIF7, PI3K/AKT, NF-κB, Nrf2/ARE, Drp1, and P-gp. In addition, HG and its derivatives antagonize inflammation through inhibiting the production and release of pro-inflammatory cytokines and inflammatory mediators by regulating inflammation-related pathways and targets, such as NF-κB, MAPK, JAK2/STAT3, Keap1-Nrf2/HO-1, and LncRNA A33/Axin2/β-catenin. Moreover, anti-pathogen, anti-metabolic disorder, anti-fibrosis, neuroprotection, and anti-depression mechanisms of HG and its derivatives have been partially elucidated. The diverse pharmacological properties of HG and its derivatives hold significant implications for future research and development of new drugs derived from HG, which can lead to improved effectiveness and safety profiles.

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Eleutherococcus nodiflorus (Dunn) S. Y. Hu is a momentous medicinal plant belonging to the Araliaceae family. In the current investigation, we determined the complete chloroplast genome of E. nodiflorus and analyzed the phylogenetic relationship among Eleutherococcus plants. The chloroplast genome of E. nodiflorus exhibited a typical quadripartite structure with a full length of 156,770 bp, including 133 genes, containing 88 protein-coding genes, 8 rRNA genes, 37 tRNA genes, and 1 presumed pseudogene ( ycf1 ). The overall GC content observed was 37.95%, with the highest GC content of 43.02% found in the IR region. Comparative genome analysis revealed five highly variable regions among Eleutherococcus species, providing potential markers for further investigations on species identification and population genetics. A total of 44 small simple repeats were identified throughout the chloroplast genome of E. nodiflorus . The phylogenetic analysis indicated a sister relationship between E. nodiflorus and E. eleutheristylus , suggesting a close genetic relationship between the two Eleutherococcus plants. These results enhance the understanding of the plant evolution within Eleutherococcus plants and provide basic genetic resources for the development of species identification and investigation of population genetic diversity of the Eleutherococcus genus and Araliaceae.

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Karst tiankengs are rare natural habitats, having a local microclimate different from surrounding regions. A contrast study on plant communities at the inside and outside of the primitive tiankeng was carried out by performing the qualitative analysis of species compositions of arborous and shrub layers. We found that plant communities in the primitive tiankeng belong to the subtropical moist evergreen broad-leaf forest, whereas those outside the tiankeng belong to subtropical semi-moist needle-broadleaved mixed forest. Trapped habitat of primitive karst tiankeng protects the plant communities significantly different from those in external karst ecosystems, so karst tiankeng has the great value in the plant species protection. Although the trapped habitat decreases plant species abundance inside tiankeng to some extent, highly diverse shrub species are present in the inside-tiankeng plant communities, and the primitive karst tiankeng plays an important role in the plant diversity protection. The primitive karst tiankeng is an important refugia for plant not only as a plant species protection library, but a plant diversity protection library. When implementing measures for the reduction of damages to biodiversity due to global climate changes and human activities, more attention should be paid to the primitive karst tiankeng as a small ecological refugia and biodiversity protection library.

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Understanding the successional process from a disturbed forest to a mature forest is essential for species recovery and conservation initiatives. The resource acquisition and drought tolerance of plants can be instructive to predictions of species abundance and distribution for different forests. However, they have not been adequately tested at different successional stages in karst regions. Here, we selected seven dominant species in an early-succession forest and 17 species in a late-succession forest in a karst region of southwestern China. Resource acquisition-related traits such as hydraulic conductivity and photosynthetic rate, and drought tolerance-related traits, including turgor loss point and wood density, were measured. We found that species in the early-succession forest had a higher hydraulic conductance and photosynthetic rate than those in the late-succession forest, while leaf water potential at turgor loss point and wood density showed nonsignificant differences between the two forests. In addition, we observed a significant negative relationship between photosynthetic rate and drought tolerance in the early-succession forest, which was not identified in late-succession forests. Our study indicates that resource acquisition rather than drought tolerance was the key factor explaining plant distributions in forests at different successional stages in karst regions. We also suggest that the resource acquisition and drought tolerance trade-off hypothesis is not always supported for karst region species. Our study could inform about the design of species replacements in successional forests and provide forest management and restoration guidelines for karst regions.

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A new triterpene, 21-O-senecioyl-R(1)-barrigenol (1) and 13 known compounds were isolated from the ethanol extracts of the leaves and bark of Pittosporum brevicalyx (Oliv.) Gagnep. Their structures were elucidated based on spectral data. The antiarrhythmic action of one furofuran lignan, liriodendrin (2), was tested on a model of CaCl(2)-induced arrhythmia and compared with the effect of verapamil. The prophylactic administration of liriodendrin (2) was effective in prolonging latency of arrhythmia and reducing the occurrence of ventricular fibrillation from 75% to 25%. The overall mortality rate was significantly reduced by the prophylactic administration of liriodendrin from 87.5% to 25%. The antiarrhythmic effect of liriodendrin (5.0 mg/kg) was similar to that of verapamil (1.05 mg/kg). Thus, liriodendrin may be a potent suppressor of CaCl(2)-induced arrhythmias.

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