The depletion of medicinal plant resources leads to the irreversible loss of their genetic diversity. The preservation of medicinal plant germplasm using cryobanks is crucial for maintaining the sustainability of these resources. This study examined the efficacy of cryopreservation on 164 medicinal plant seeds, identified general principles for preserving medicinal plant seeds at ultra-low temperatures, and established a cryobank for dry-sensitive medicinal plant seeds. Over 90% of orthodox seeds were unaffected by freezing, with optimal conditions being a 5–10% moisture content and direct freezing. Intermediate seeds were best frozen with a 7–15% moisture content, and those with a lower initial moisture content were best suited to direct freezing. While recalcitrant seeds’ freezing was most influenced by moisture content, there was no specific range. Direct freezing is appropriate for recalcitrant seeds possessing a hard seed coat and a firm seed kernel, whereas seeds with a brittle or soft seed coat are better suited for vitrification or stepwise freezing methods. There was no significant correlation between alterations in physiological and biochemical indicators and microscopic structures of seeds before and following liquid nitrogen freezing, as well as their storage characteristics. The findings of this research offer evidence in favor of the extended conservation of plant seeds and the extensive utilization of ultra-low temperature technology and provides an example of protecting the genetic diversity of plant resources.

Five new naphthalene derivatives, named Eleutherols A–C (1–3) and Eleuthinones B–C (4,5), together with three known compounds were isolated from the bulbs of Eleutherine americana. Their structures were elucidated on the basis of spectroscopic analysis including HR-ESI-MS, 1D and 2D NMR techniques. These compounds exhibited a potent effect against the injury of human umbilical vein endothelial cell (HUVECs) induced by high concentrations of glucose in vitro.

Five new cucurbitane-typetriterpenoid glycosides, named Xuedanoside F–J (1–5), were obtained from the rhizomes of Hemsleya penxianensis (Xue dan), which belongs to the family of Cucurbitaceae. These new compounds were elucidated byspectroscopic analysis, including 1D, 2D NMR, and HR-ESI-MS spectra. Additionally, all the isolates were evaluated for cytotoxicity against three human cancer cell lines (Hela, MCF-7, and A-549) with the IC₅₀ ranging from 2.25 to 49.44 µM in vitro with treatment 48 h and showed low cytotoxicity in human normal liver L-02 cells (IC₅₀ > 50 µM). Compound 5 showed the most significant cytotoxic activity with the IC₅₀ value of 2.25, 4.72, and 5.33 µM in 48 h, respectively.

Dalbergia odorifera T. Chen possesses significant aromatic, medicinal, and timber value, yet its wild populations are critically endangered due to habitat degradation. Breeding programs are urgently needed to address resource shortages, but the suitability of large-scale plantations as alternative genetic resources remains unverified. This study systematically evaluated the genetic diversity of 380 individuals from five populations using 24 polymorphic SSR markers, identifying 278 alleles. The results demonstrated a moderate level of genetic diversity in plantation populations, comparable to wild resources. Additionally, nine phenotypic traits were measured in 70 individuals. Correlation analysis revealed that the heartwood ratio (HWR) was significantly positively correlated with diameter at breast height (DBH) and ground diameter (GD) (p ≤ 0.05). Our association analysis, based on general linear (GLM) and mixed linear models (MLM), revealed two key findings: one locus (96c-345) was significantly associated with diameter traits, and four loci (34a-241, S03-265, JXHT097-252, JXHT136-270) were strongly linked to the HWR (p ≤ 0.01). This research provides initial evidence that plantations are viable substitutes for wild germplasm and establishes a foundation for marker-assisted breeding in this valuable species.