Arctium species are known for a variety of pharmacological effects due to their diverse volatile and non-volatile secondary metabolites. Representatives of Arctium species contain non-volatile compounds including lignans, fatty acids, acetylenic compounds, phytosterols, polysaccharides, caffeoylquinic acid derivatives, flavonoids, terpenes/terpenoids and volatile compounds such as hydrocarbons, aldehydes, methoxypyrazines, carboxylic and fatty acids, monoterpenes and sesquiterpenes. Arctium species also possess bioactive properties such as anti-cancer, anti-diabetic, anti-oxidant, hepatoprotective, gastroprotective, antibacterial, antiviral, antimicrobial, anti-allergic, and anti-inflammatory effects. This review aims to provide a complete overview of the chemistry and biological activities of the secondary metabolites found in therapeutically used Arctium species. Summary of pharmacopeias and monographs contents indicating the relevant phytochemicals and therapeutic effects are also discussed, along with possible safety considerations.

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The current study aimed to identify which natural products and which research directions are related to the major contributors to academic journals for diabetes therapy. Bibliometric data were extracted from the Web of Science online database using the search string TOPIC ¼ (''natural product à ' OR ''natural compound à ' OR ''natural molecule à ' OR 'phytochemical à ' OR ''secondary metabolite à ') AND TS ¼ ('diabet à ') and analysed by a bibliometric software, VOSviewer. The search yielded 3694 publications, which were collectively cited 80,791 times, with an Hindex of 117 and 21.9 citations per publication on average. The top-contributing countries were India, the USA, China, South Korea and Brazil. Curcumin, flavanone, resveratrol, carotenoid, polyphenols, flavonol, flavone and berberine were the most frequently cited natural products or compound classes. Our results provide a brief overview of the major directions of natural product research in diabetes up to now and hint on promising avenues for future research.

In high‐temperature proton exchange membrane fuel cells (HT‐PEMFCs), the poisoning of Pt by phosphoric species severely affects the kinetics of the oxygen reduction reaction, which restricts their commercialized application. Herein, for the first time, the phosphate tolerance of PtFe ordered intermetallic alloys is enhanced by a doping‐modulated strain strategy via employing a low amount of Cu as a dopant to boost HT‐PEMFCs. This Cu doping facilitates the formation of compressive strain in PtFe crystals, consequently altering the electronic structure of electrocatalysts and then benefiting for weakening the adsorption energy between phosphoric acid and Pt surfaces. In addition, the high temperature phosphate adsorption tests also reveal that the dopant of Cu in Pt based electrocatalysts can improve the tolerance of phosphoric acid. The HT‐PEMFCs assembled by those cathodic electrocatalysts with the low‐Pt loading of 0.5 mgPt cm−2 achieve a preeminent peak power of 793.5 and 432.6 mW cm−2 under the condition of H2–O2 and H2–air atmosphere, respectively, or nearly 1.53 and 1.34 times higher as compared with commercial Pt/C electrocatalysts. Moreover, those electrocatalysts also exhibit robust stability under harsh condition in H2–O2 atmosphere with negligible activity loss for at least 100 h, exceeding most of other reported ORR electrocatalysts.

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A grand challenge in natural product chemistry is to determine the biological effects of all natural products. A phenotypic approach is frequently used for determining the activity of a compound and its potential impact on a disease state. Chemical investigation of a specimen of Jaspis splendens collected from the Great Barrier Reef resulted in the isolation of a new pterin derivative, jaspterin (1), a new bisindole alkaloid, splendamide (2), and a new imidazole alkaloid, jaspnin A (3) TFA salt. Jaspamycin (8) and 6-bromo-1H-indole-3-carboximidamide (16) are reported for the first time as naturally occurring metabolites. Known nucleosides (4-7, 9, 10), aglycones (11-13), indole alkaloids (14, 15, 17), and jaspamide peptides (18-22) were also isolated. The structures of the three new compounds 1-3 were unambiguously elucidated based on NMR and mass spectroscopic data. Jaspnin A (3) contained a rare thiomethylated imidazolinium unit. Coupling an unbiased phenotypic assay using a human olfactory neurosphere-derived cell model of Parkinson's disease to all of the natural products from the species J. splendens allowed the phenotypic profiles of the metabolites to be investigated.

Three members of a new class of ascorbic acid-adduct indole alkaloids (1-3), a new prenylated indole alkaloid (4), and five known compounds (5-9) were isolated from the leaves of Flindersia pimenteliana. The structures of 1-4 were elucidated on the basis of their (+)-HRESIMS and 2D NMR spectroscopic data. Antiplasmodial activity was also reported for the natural products against chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) Plasmodium falciparum with IC values ranging from 0.19 to 3.6 μM.