Dendrobium Sw. is one of the largest genera in the orchidaceous family and includes 900-2000 species. Among them, more than 80 Dendrobium species have been reported in China. However, there are only six Dendrobium species, namely, D. bigibbum var. superbum (syn. D. phalaenopsis), D. chrysanthum, D. fi mbriatum, D. loddigesii, D. nobile, and D. officinale (syn. D. candidum), listed in the New Inventory of Existing Cosmetic Ingredients in China Launched. Artificial planting of Dendrobium species has been a great success in China. To better utilize Dendrobium resources for medicinal and cosmetic purposes, we summarize their traditional uses and pharmacologically active compounds for treating dermatological disorders in this review. "Orchidaceae", "Dendrobium", "traditional use", "ethnobotany", "dermatological disorder", and "skin disease" were used as search terms to screen the literature. Cited references were collected between 1970 and 2020 from the Web of Science, China National Knowledge Internet (CNKI), SciFinder, Google Scholar, and Chinese books. From the search, it was found that there are 22 Dendrobium species with traditional uses in dermatological disorders, and 131 compounds from Dendrobium plants have been reported to possess anti-inflammatory, antimicrobial, antioxidant, antiaging, anti-psoriasis, and tyrosinase-inhibitory activities, implying that Dendrobium plants are important resources for the discovery of active compounds and the development of new drugs and cosmetics. D. crepidatum, D. denneanum, D. loddigesii, D. nobile, and D. officinale have been extensively studied. More research on other Dendrobium species is needed. The major active compounds found in Dendrobium species are phenanthrenes, alkaloids, flavonoids, phenylpropanoids, and lignans. Several compounds, such as loddigesiinol A, (S)-5-methoxy-2,4,7,9-tetrahydroxy-9,10-dihydrophenanthrene, (S)-4-methoxy-2,5,7,9-tetrahydroxy-9,10-dihydrophenanthrene, 2,5-dihydroxy-4-methoxy-phenanthrene 2-O-β-D-glucopyranoside, (9R)-1,2,5,9-tetrahydroxy-9,10-dihydrophenanthrene 5-O-β-D-glucopyranoside, (+)-homocrepidine A, and vicenin 2, have significant anti-inflammatory activities and inhibit nitric oxide (NO) production with IC₅₀ values less than 5 μM, and these compounds are worthy of further study.

Despite advancements in the areas of omics and chemoinformatics, potent novel biotherapeutic molecules with new modes of actions are needed for leishmaniasis. The socioeconomic burden of leishmaniasis remains alarming in endemic regions. Currently, reports from existing endemic areas such as Nepal, Iran, Brazil, India, Sudan and Afghanistan, as well as newly affected countries such as Peru, Bolivia and Somalia indicate concerns of chemoresistance to the classical antimonial treatment. As a result, effective antileishmanial agents which are safe and affordable are urgently needed. Natural products from both flora and fauna have contributed immensely to chemotherapeutics and serve as vital sources of new chemical agents. This review focuses on a systematic cross-sectional view of all characterized anti-leishmanial compounds from natural sources over the last decade. Furthermore, IC₅₀/EC₅₀, cytotoxicity and suggested mechanisms of action of some of these natural products are provided. The natural product classification includes alkaloids, terpenes, terpenoids, and phenolics. The plethora of reported mechanisms involve calcium channel inhibition, immunomodulation and apoptosis. Making available enriched data pertaining to bioactivity and mechanisms of natural products complement current efforts geared towards unraveling potent leishmanicides of therapeutic relevance.

One novel spirolactone, aquilarisinolide (1), three new sesquiterpenoids, (2R,4S,5R,7R)-2-hydroxyeremophila-9,11-dien-8-one (2), (1R,4S,5S,7R,11R)-13-hydroxyepidaphnauran-9-en-8-one (3), and (4R,5S,7R,8S,10S,13R)-8,13-dihydroxyrotunda-1,11-dien-3-one (4), together with 13 known compounds (5-17) were isolated from the resinous heartwood of Aquilaria sinensis (Thymelaeaceae). The structures of the new compounds were elucidated based on the analysis of NMR and MS data and theoretical calculations their ECD spectra. The isolated compounds were evaluated for their protective activities against PC12 cell injury induced by corticosterone (CORT) and 1-methyl-4-phenylpyridine ion (MPP⁺), as well as inhibitory activities against BACE1. Compound 4, 5,6-dihydroxy-2-(2-phenylethyl) chromone (5), daphnauranol B (7), 6-methoxy-2-[2-(3-methyoxyphenyl) ethyl]chromone (10), isoagarotetrol (14), and 1-hydroxy-1,5-diphenylpentan-3-one (16) showed significant protective effects on CORT-induced injury in PC12 cells at a concentration of 20 μM (P < 0.001). Isoagarotetrol (14) showed a significant protective effect on MPP⁺-induced injury in PC12 cells at a concentration of 20 μM (P < 0.001), while compound 4 showed a moderate activity (P < 0.01). The BACE1-inhibitory activities of all tested compounds were very weak with less than 30% inhibition at a concentration of 20 μM.

Three new clerodane-type diterpene glycosides, (5R,6S,8R,9S,10R)-6-O-[β-D-glucopyranosyl-(1→4)-α-L-rhamnopyranosyl] cleroda-3,13(16),14-diene (1), (5R,6S,8R,9S,10R,13S)-6-O-[β-D-glucopyranosyl-(1→ 4)-α-L-rhamnopyranosyl]-2-oxoneocleroda-3,13-dien-15-ol (2), (5R,6S,8R,9S,10R)-6-O-[β-D-glucopyranosyl-(1→ 4)-α-L-rhamnopyranosyl]-(13E)-2-oxoneocleroda-3,14-dien-13-ol (3), together with two known compounds 4 and 5 were isolated from Dicranopteris pedata. The structures of these compounds were elucidated by detailed spectroscopic analysis, and the absolute configuration of compound 2 was determined by ECD calculations. In addition, compound 1 exhibited weak inhibitory activities against SMMC-7721, MCF-7 and SW480.

The extensive chemical investigation on the branches and leaves of Terminalia chebula var. tomentella (Combretaceae) led to the isolation of two new lignan glucosides with a furofuran skeleton, termitomenins F (1) and G (2). In addition, 19 known compounds including five lignan glucosides (3-7), six hydrolyzable tannins (8-13) and eight simple phenolics (14-21) were also identified. Their structures were determined by comprehensive spectroscopic analyses. It is noted that 8 and 9 were C-glycosidic hydrolyzable tannins with one hexahydroxydiphenoyl and one gallagyl group linked to an open-chain glucosyl C-1/O-2/O-3 and O-4/O-6, respectively, which were rarely found in plants. Nine known compounds, 6-9, 13, and 18-21, were procured from the titled plant for the first time, while 3-5, 10-12 and 14-17 were also found in the fruits. Notably, the known hydrolyzable tannins 8-13 exhibited stronger α-glucosidase inhibitory activities with IC₅₀ values ranging from 0.10 to 3.12 μM, than the positive control, quercetin (IC₅₀=9.38 ±0.33 μM).