Chromosome level genome assembly of endangered medicinal plant Anisodus tanguticus

Anisodus tanguticus is a medicinal herb that belongs to the Anisodus genus of the Solanaceae family. This endangered herb is mainly distributed in Qinghai-Tibet Plateau. In this study, we combined the Illumina short-read, Nanopore long-read and high-throughput chromosome conformation capture (Hi-C) sequencing technologies to de novo assemble the A. tanguticus genome. A high-quality chromosomal-level genome assembly was obtained with a genome size of 1.26 Gb and a contig N50 of 25.07 Mb. Of the draft genome sequences, 97.47% were anchored to 24 pseudochromosomes with a scaffold N50 of 51.28 Mb. In addition, 842.14 Mb of transposable elements occupying 66.70% of the genome assembly were identified and 44,252 protein-coding genes were predicted. The genome assembly of A. tanguticus will provide genetic repertoire to understand the adaptation strategy of Anisodus species in the plateau, which will further promote the conservation of endangered A. tanguticus resources.

New indolizidine- and pyrrolidine-type alkaloids with anti-angiogenic activities from Anisodus tanguticus

Eleven alkaloids, including five previously undescribed indolizidine alkaloids (1, 2a, 2b, 3a, and 3b) and four new pyrrolidine alkaloids (5-8), were isolated from the roots of Anisodus tanguticus. Of these, two new pairs of enantiomeric alkaloids (2a/2b and 3a/3b) are the first examples of alkaloids containing both indolizidine and pyrrolidine structural fragments. The one-carbon bridge connections with two pyrrolidine rings (6) or with a pyrrolidine ring and a pyridine ring (8) are the first reported from nature. Extensive spectroscopic techniques were used to elucidate their structures, and NMR and ECD calculations were used to determine the absolute configurations. The viability of human umbilical vein endothelial cells (HUVECs) was inhibited by compounds 2a, 2b, 3a, 4b, and 5, and compound 2b exhibited a potential anti-angiogenic effect by inhibiting the proliferation, migration, and tube formation of HUVECs. A chorioallantoic membrane assay also demonstrated the anti-angiogenic activity of 2b. In addition, compounds 2a, 2b, 3a, and 4b exhibited moderate cytotoxicity against A2780 cells.

Long-Term Impact of N, P, K Fertilizers in Different Rates on Yield and Quality of Anisodus tanguticus (Maxinowicz) Pascher

Anisodus tanguticus (Maxinowicz) Pascher (Solanaceae) is a traditional Chinese herb that is widely used in folklore and clinical practice. In recent years, wild populations have been severely impacted to the point of extinction due to over-harvesting and reclamation. Therefore, artificial cultivation is important to relieve the pressure of market demand and protect wild plant resources. Using a "3414" fertilization design, i.e., 3 factors (N, P, and K), 4 levels, and 14 fertilization treatments, with 3 replicates and a total of 42 experimental plots, A. tanguticus was harvested in October 2020, June 2021, August 2021, and October 2021, and the yield and alkaloid content were determined. The study aimed to provide a theoretical basis and technical reference for the standardization of A. tanguticus cultivation. Biomass accumulation and alkaloid content showed a trend of increasing and then decreasing with the application of nitrogen, phosphorus, and potassium, and the biomass accumulation was the highest at the application levels of nitrogen and phosphorus in T6 and T9 and at the application levels of medium and low potassium. The alkaloid content showed an increasing trend between October of the first year and June of the second year and a decreasing trend in the second year with the increase in the harvesting period. Yield and alkaloid yield showed a decreasing trend between October of the first year and June of the second year and an increasing trend in the second year with the increase in the harvesting period. The recommended application rates are 225-300 kg/ha² for nitrogen, 850-960 kg/ha² for phosphorus, and 65-85 kg/ha² for potassium.

Novel Indane Derivatives with Antioxidant Activity from the Roots of Anisodus tanguticus

Four novel indane derivatives, anisotindans A-D (1-4), were isolated from the roots of Anisodus tanguticus. Their structures were established using comprehensive spectroscopic analyses, and their absolute configurations were determined by electronic circular dichroism (ECD) calculations and single-crystal X-ray diffraction analyses. Anisotindans C and D (3 and 4) are two unusual indenofuran analogs. ABTS^•+ and DPPH^•+ assays of radical scavenging activity reveal that all compounds (1-4) are active. Specifically, the ABTS^•+ assay results show that anisotindan A (1) exhibits the best antioxidant activity with an IC₅₀ value of 15.62 ± 1.85 μM (vitamin C, IC₅₀ = 22.54 ± 5.18 μM).

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A personal selection of 32 recent papers is presented covering various aspects of current developments in bioorganic chemistry and novel natural products such as anisotanol A from Anisodus tanguticus.