Three new depsidones, parmosidones F – G (1 – 2), and 8′-O-methylsalazinic acid (3), and 3 new diphenylethers, parmetherines A – C (4 – 6), together with 2 known congeners were isolated from the whole thalli of Parmotrema dilatatum, a foliose chlorolichen. Their structures were unambiguously determined by extensive spectroscopic analyses and comparison with literature data. The isolated polyphenolics were assayed for their α-glucosidase inhibitory activities. Newly reported benzylated depsidones 1 and 2 in particular inhibited α-glucosidase with IC50 values of 2.2 and 4.3 µM, respectively, and are thus more potent than the positive control, acarbose.

Two new cycloartanes, combretic acid C (1) and combretanone I (3), were isolated from the leaves of Combretum quadrangulare Kurz, together with the previously-reported combretic acids A-B (2 and 5) and combretanone A (4). An extensive set of spectroscopic methods were used to elucidate the structures of these compounds. Cytotoxicity against the K562 cancer cell line was evaluated.Compound 1 showed strong activity, with an IC50 value of 9.7 µM. The other compounds showed moderate activity. Alpha-glucosidase inhibition was also evaluated. The isolated compounds showed moderate inhibition, with IC50 values in the range 102.2-194.7 µM.

Chemical investigation of the lichen Parmotrema tsavoense led to the isolation of 5 new depsidones, parmosidones F – J (1 – 5). These compounds were structurally elucidated using spectroscopic methods including HRESIMS and 2D NMR data. Compounds 1, 3, and 4 were evaluated for their inhibition of α-glucosidase. All exhibited potent α-glucosidase inhibitory activity with IC50 values ranging from 10.7 to 17.6 µM, which was much lower than that of the positive control acarbose (IC50 449 µM).

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Cordyceps is a well-known and valuable fungal Chinese medicine and health food. The polysaccharides from C. sinensis have been reported as the main bioactive components, which possess antioxidant, anti-aging, and liver protective activities. This study aimed to investigate the in vitro antioxidative and protective effects of exopolysaccharides (EPS) from cultivated Ophiocordyceps sinensis (O. sinensis) on rats with liver damage induced by CCl4. The results indicated that cultivated O. sinensis EPS possess moderate ABTS and hydroxyl radical scavenging abilities with IC50 values of 2.00 and 3.78 mg/mL, respectively. EPS and the positive control (silymarin) could also protect rat liver from the oxidative effect induced by CCl4 via increasing GSH levels, reducing MAD levels and decreasing serum AST and ALT activities. Moreover, the changes in histopathological liver tissue showed that EPS significantly reduced the damage induced by CCl4 in the liver. The findings suggest that EPS possesses a significant hepatoprotective effect against hepatotoxicity induced by CCl4 in rats.