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The first phytochemical investigation of Polyalthia cinnamomea led to the isolation and identification of two new oxoprotoberberine alkaloids, (-)-(13aS)-polyalthiacinnamines A and B, together with eleven known compounds. The structures of the new compounds were elucidated by extensive spectroscopic methods. The absolute configuration of miliusacunine E and consanguine B was established by X-ray diffraction analysis using Cu Kα radiation and ECD spectra, whereas the absolute configurations of polyalthiacinnamines A and B were established by comparison of their ECD spectra and specific rotations with those of miliusacunine E and consanguine B. Compounds 1-4, 6, and 8 exhibited α-glucosidase inhibitory activities (IC 50 values ranging from 11.3 to 57.9 µM) better than a positive control (acarbose, IC 50 83.5 μM). Compound 2 also exhibited NO production inhibitory activity with an IC 50 value of 24.4 μM (indomethacin, a positive control, IC 50  = 32.2 μM)., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Five new compounds-two phloroglucinol benzophenones, garciniacowones F ( 1 ) and G ( 2 ), and three xanthones, garciniacowones H ( 3 ), I ( 4 ), and J ( 5 )-together with seven known xanthones ( 6 - 12 ) were isolated from the fresh leaves of Garcinia cowa . Their structures were elucidated by detailed analysis of NMR and MS data. Compounds 1 and 2 are phloroglucinol benzophenones containing a polyprenylated bicyclo[3.3.1]nonane ring system, while compounds 3 - 5 are rare xanthones having farnesyl ( 3 and 5 ) and geranylgeranyl ( 5 ) units at C-8. Compounds 1 , 3 , 4 , 7 , 8 , and 10 exhibited inhibitory effects on NO production in LPS-induced RAW264.7 macrophage cells with IC 50 values ranging from 5.4 to 18.6 μM. Compounds 4 and 8 had α-glucosidase inhibitory activities with IC 50 values of 15.4 and 11.4 μM, respectively, which were more potent than that of the acarbose control.

Ganoderma (Ganodermataceae) has a worldwide distribution and has been widely used in traditional medicines. In this study, we report wild strains of Ganoderma that include two G. sichuanense and one G. orbiforme from northern Thailand. Optimal conditions for mycelium growth were ensured. The most favourable medium was potato sucrose agar for G. sichuanense and oatmeal agar for G. orbiforme and at 25 °C and 30 °C and pH 4–8. All types of cereal grains can be used to promote the growth of the mycelia of Ganoderma species. Fruiting tests were performed. All strains of Ganoderma produce fruiting bodies successfully in bag culture at 28 ± 1 °C with 75–85% relative humidity. Only G. orbiforme produced fruiting bodies in field cultivation at the laboratory scale. In the first flush yields, the G. sichuanense strain MFLUCC 22-0064 gave better production (the B.E was 152.35 ± 6.98 g). This study is the first to document the bag and field cultivation of wild Thai G. orbiforme. Ganoderma species are revealed to contain high amounts of fiber (47.90–52.45% d.b.), protein (12.80–14.67% d.b.), fat (4.90–5.70% d.b.), and carbohydrates (3.16–4.02% d.b.). Additionally, G. sichuanense and G. orbiforme were preliminarily screened for biological activity for inhibition of alpha–glucosidase enzyme activity. The IC50 values of G. orbiforme (MFLUCC 22-0066) was 105.97 ± 1.36 µg/mL and G. sichuanense (MFLUCC 22-0064) was 126.94 ± 0.87 µg/mL. Both strains had better inhibition than acarbose (168.18 ± 0.89 µM). These results on wild strains of Ganoderma will be useful for further studies on the applications of Ganoderma. Later the species can be introduced to domestic markets for cultivation and medicinal use. [ABSTRACT FROM AUTHOR]

A new geranylated xanthone, nigrolineaxanthone AA (1) together with 18 known compounds (2–19) were isolated from latex and twig extracts of Garcinia nigrolineata Planch. ex T. Anderson. Some of the isolated compounds were assessed for their antidiabetic activities and cytotoxicity against three cancer cell lines. Of these, compounds 12 (IC50 value of 25.8 ± 0.2 µM), 16 (IC50 value of 124.8 ± 0.7 µM), and 17 (IC50 value of 44.4 ± 1.1 µM) exhibited the highest α-glucosidase inhibitory, α-amylase inhibitory, and glycation inhibition activities, respectively. Compound 11 showed glucose consumption and glucose uptake with IC50 values of 14.2 ± 0.8 µM and 3.1-fold. Compound 10 displayed cytotoxic activity against colon cancer (SW480) with an IC50 value of 4.3 ± 0.1 µM), while compound 2 showed cytotoxicity against leukemic cancer (K562) with IC50 value of 4.4 ± 0.3 µM. [ABSTRACT FROM AUTHOR]

Gonioridleylactam (1), a new compound, is a unique dimeric aristolactam isolated from the EtOAc extract of the twigs of Goniothalamus ridleyi King. The structure of gonioridleylactam (1) consists of two different aristolactams linked together with two methylenedioxy bridges at C–3/C–3′ and C–4/C–4′, generating a ten-membered ring of [1,3,6,8]tetraoxecine. A new natural product, gonioridleyindole (3-hydroxymethyl-1-methyl-1H-benz[f]indole-4,9-dione, 2), together with eight known compounds (3–10) were also isolated from this plant. Their structures were extensively characterized by spectroscopic methods and comparisons were made with the literature. Compounds 1–4, 7, and 9 were evaluated for their α-glucosidase inhibitory activity. Of these, 3,5-demethoxypiperolide (7) displayed the highest α-glucosidase inhibitory activity, with an IC50 value of 1.25 µM. [ABSTRACT FROM AUTHOR]

A new C-benzylated flavone, uvariaruflavone (1), along with 13 known compounds (2–14) were isolated from the twig and leaf extracts of Uvaria rufa Blume. Their structures were established by extensive spectroscopic methods. Flavones (5–8) and cyclohexene (10) were isolated from U. rufa for the first time. Most of the isolated compounds were evaluated for their α-glucosidase and α-amylase inhibitory activities. Of these, uvariaruflavone (1) showed the highest α-glucosidase inhibitory activity with an IC50 value of 44.3 µM, while ferrudiol (12) displayed the highest α-amylase inhibitory activity with an IC50 value of 73.5 µM. [ABSTRACT FROM AUTHOR]