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Summary: α‐Glycosidase, a critical therapeutic target in type 2 diabetes mellitus (T2DM), can be modulated by inhibitors to reduce postprandial blood glucose levels. This study investigated the inhibitory effects of vine tea (Ampelopsis grossedentata) and its key compounds on α‐glycosidase. The results demonstrated that fifteen varieties of vine tea extracts inhibited α‐glycosidase in a dose‐dependent manner, with IC50 values ranging from 5.25 to 35.8 μg mL−1. HPLC analysis revealed dihydromyricetin (DHM) as the main compound in vine tea, with an IC50 value of 262.50 μM. Notably, the synergistic combination of DHM and the antidiabetic drug acarbose (ABS) significantly enhanced inhibitory effectiveness, with the optimal ratio (1:125) yielding a potentiation index (CI) of 0.09. Fluorescence and molecular docking analyses supported the hypothesis that DHM enhanced ABS's inhibitory effect through complex formation and specific interactions, offering a promising option for safer and more effective diabetes therapy. [ABSTRACT FROM AUTHOR]

Two new benzoic acids, cladoslide A (1) and cladoslide B (2); one new β-carboline derivative, cladospomine (3); and one new pyridin-2(1H)-one, cladoslide C (4), were isolated from the fermentation cultures of the mangrove-derived fungus Cladosporium sp. HNWSW-1, along with the previously reported N-acetyl-β-oxotryptamine (5), (4S,5S,11R)-iso-cladospolide B (6), (4S,5S,11S)-iso-cladospolide B (7), and (4R,5S,11R)-iso-cladospolide B (8). Their structures were elucidated by spectroscopic analysis, Rh2(OCOCF3)4-induced ECD experiments, and Marfey’s method. Compound 1 showed cytotoxicity against the K562 cell line with IC50 values of 13.10 ± 0.08 μM. Moreover, compounds 1 and 5 exhibited inhibitory activity against α-glycosidase with IC50 values of 0.32 ± 0.01 mM and 0.17 ± 0.01 mM, respectively.

Chronic hyperglycemia induces activation of the polyol‐sorbitol pathway, which is a major contributor to microvascular complications like stroke. The current study was designed to elucidate the therapeutic role of α‐glucose inhibitor in chronic hyperglycemia‐induced impaired polyol pathway and associated micro‐complications. Male albino‐Wistar rats (200–250 g) were treated with voglibose 10 mg kg−1 day−1/p.o. for 2 weeks before middle cerebral artery occlusion; 72 hr after surgery, neurological score was evaluated and blood was collected for the assessment of various serum biochemical parameters like CRP, CK‐MB, LDH, lipid profile, and blood glucose levels. In the end, brain samples were excised for determination of brain infarct volume, brain hemisphere weight difference, Na+‐K+ ATPase activity oxidative stress‐related parameters, aldose reductase activity, and gene expression studies. Results from the present study indicate that pre‐treatment with voglibose showed significant improvement in lipid parameters but did not impact glucose levels. Voglibose has shown a statistically significant (p <.05) reduction in neurological score and brain infarct volume, and the difference in brain hemisphere weight as compared to the disease control group. Voglibose significantly (p <.05) improve all biochemical parameters and reduced Na+‐K+ ATPase and aldose reductase activity. Moreover, voglibose produced a significant reduction in oxidative stress and down‐regulation of TNF‐α and BCl‐2 gene expression which reduces the risk of factors related to stroke. In conclusion, the pleiotropic effect of voglibose on cerebrovascular complications may be due to inhibition of aldose reductase or anti‐inflammatory pathways. [ABSTRACT FROM AUTHOR]

Four picrotoxane-type sesquiterpenes, dendroterpene A–D (1–4), together with four known compounds (5–8), were isolated from the stems of Dendrobium nobile Lindl. Their structures were elucidated by spectroscopic analysis, X-ray diffraction analysis, analysis of the ECD data according to the Klyne's lactone sector rule, and quantum ECD calculation. Compounds 1 and 2 are two new picrotoxane-type sesquiterpenes with a new carbon skeleton containing a formamide group, which may be derived from the previously reported dendrobiumane B skeleton by the C(9)-C(11) carbon bond cleavage. Compounds 3, 5, 6, and 8 exhibited inhibitory activity against α-glycosidase. Compounds 5 and 6 were cytotoxic against SGC-7901, K562, A549, BEL-7402, and Hela cell lines.

Abstract The α-glycosidase inhibition assay is used to examine the inhibition activity of traditional Chinese medicines through extraction with methanol. The α-glycosidase inhibition activity of the isolated compounds is measured by α-glycosidase inhibition assay and compared with Acarbose. Molecular docking is implemented to study the interaction between isolated compounds and CtMGAM (maltase–glucoamylase-C) or NtMGAM (maltase–glucoamylase-N). Compared with those of Acarbose, the methanol extract of Gardenia jasminoides Ellis has a higher activity to inhibit α-glycosidase among the 74 traditional Chinese medicines. Geniposide and Gardenoside, isolated compounds from Gardenia jasminoides Ellis , have better inhibition activity (IC 50 values of 0.35 and 0.46 mg/ml, respectively) than Acarbose (IC 50 values of 0.75 mg/ml). The molecular docking results show that Geniposide and Gardenoside have specific binding affinities with CtMGAM and can be considered comparable to those of Acarbose. Our findings illuminate the possible anti-diabetic mechanism of Gardenia jasminoides Ellis and support its use for the treatment of diabetes. Highlights • We illuminate the anti-diabetic mechanism for supporting the use of Geniposide and Gardenoside in the near future. [ABSTRACT FROM AUTHOR]

Introduction Cassia grandis Lf fruits are ethnobotanically used for digestive disorders, anemia, and for reducing blood glucose. However, there are no studies about the antidiabetic activity nor the oral toxicity of the plant fruit-extracts. This paper aims to evaluate the hypoglycemic effect of C. grandis fruits extract in vivo, and assess the acute oral toxicity, and sub-acute oral toxicity. The antioxidant activity and the α-glycosidase inhibitor effect were also evaluated. Methods The extract was obtained by maceration of the fruit pulp with 70% hydroalcoholic solution (1:2, m:v). The extractive solution was concentrated in a vacuum rotary evaporator, up to a drug: solvent ratio of 2:1 (g/ml). Soluble solids, relative density, refractive index, pH, total phenolics, and flavonoids were determined. A preliminary phytochemical screening was made, followed by the quantitation of volatiles by GC/MS. The acute and sub-acute oral toxicity was evaluated in Sprague Dawley rats, by using biochemical and hematological parameters. The radical scavenging activity (DPPH , ABTS ) and α-glycosidase inhibitory effect were tested. The hypoglycemic effect was assessed in alloxan-induced diabetic rats. Results The extract of C. grandis contains alkaloids, coumarins, flavonoids, free amino acids, amines, phenols, tannins, reduced sugars, resins, saponins, steroids, and triterpenes, plus 38 volatile compounds, being linalool the most abundant (1,66%). The extract exhibited an LD 50  > 2000 mg/kg, and after a continuous administration (1000 mg/kg, 28-days), the hematological and biochemical parameters were normal. The extract showed hypoglycemic effect, being the dose 200 mg/kg no statistically different from glibenclamide at 25 mg/kg. Good antioxidant activity and a potent α-glycosidase inhibitory effect were also observed. Conclusion C. grandis extract is an excellent hypoglycemic and non-toxic plant product. The hypoglycemic mechanism could be associated with the antioxidant effect and with the α-glycosidase inhibition. Up to the best of our knowledge, this is the first report on the hypoglycemic effect in vivo of C. grandis fruits extract. [ABSTRACT FROM AUTHOR]

Two new succinimide-containing derivatives, cladosporitins A (1) and B (2), were isolated from the fermentation cultures of the mangrove-derived fungus Cladosporium sp. HNWSW-1, along with a new pyrone, clapone (3), as well as the previously reported talaroconvolutin A (4) and anthraquinone (5). The structures of the isolated compounds were elucidated by 1D, 2D NMR, and HRMS spectral analysis. Compound 2 showed cytotoxicity against BEL-7042, K562 and SGC-7901 cell lines with IC50 values of 29.4 ± 0.35 μM, 25.6 ± 0.47 μM, and 41.7 ± 0.71 μM, respectively, whereas compound 4 exhibited cytotoxicity against Hela and BEL-7042 cell lines with IC50 values of 14.9 ± 0.21 μM and 26.7 ± 1.1 μM, respectively. In addition, compounds 4 and 5 displayed inhibitory activity against α-glycosidase, with IC50 values of 78.2 ± 2.1 μM and 49.3 ± 10.6 μM, respectively.

Abstract: The effect of a methanol extract of Rosa damascena Mill. flowers was studied, in comparison to the α-glucosidase inhibitor acarbose, in normal and diabetic rats. The inhibition mode of this extract was examined by measuring enzyme activity in different concentrations of substrate for Lineweaver–Burk plot analysis. The results show that Rosa damascena extract has an intensive inhibitory effect on α-glucosidase. Its inhibition was found to be noncompetitive. Oral administration of this plant extract (100 to 1000mg/kg body wt.) significantly decreased blood glucose after maltose loading in normal and diabetic rats in a dose-dependent manner. These results suggest that Rosa damascena might exert an anti-diabetic effect by suppressing carbohydrate absorption from the intestine and can reduce the postprandial glucose level. [Copyright &y& Elsevier]

Two new benzoic acids, cladoslide A ( 1 ) and cladoslide B ( 2 ); one new β-carboline derivative, cladospomine ( 3 ); and one new pyridin-2(1 H )-one, cladoslide C ( 4 ), were isolated from the fermentation cultures of the mangrove-derived fungus Cladosporium sp. HNWSW-1, along with the previously reported N -acetyl-β-oxotryptamine ( 5 ), (4 S ,5 S ,11 R )- iso -cladospolide B ( 6 ), (4 S ,5 S ,11 S )- iso -cladospolide B ( 7 ), and (4 R ,5 S ,11 R )- iso -cladospolide B ( 8 ). Their structures were elucidated by spectroscopic analysis, Rh 2 (OCOCF 3 ) 4 -induced ECD experiments, and Marfey's method. Compound 1 showed cytotoxicity against the K562 cell line with IC 50 values of 13.10 ± 0.08  μ M. Moreover, compounds 1 and 5 exhibited inhibitory activity against α-glycosidase with IC 50 values of 0.32 ± 0.01 mM and 0.17 ± 0.01 mM, respectively., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Cao, Guo, Cai, Kong, Yuan, Gai, Dai, Wang and Mei.)

Two new succinimide-containing derivatives, cladosporitins A (1) and B (2), were isolated from the fermentation cultures of the mangrove-derived fungus Cladosporium sp. HNWSW-1, along with a new pyrone, clapone (3), as well as the previously reported talaroconvolutin A (4) and anthraquinone (5). The structures of the isolated compounds were elucidated by 1D, 2D NMR, and HRMS spectral analysis. Compound 2 showed cytotoxicity against BEL-7042, K562 and SGC-7901 cell lines with IC50 values of 29.4 ± 0.35 μM, 25.6 ± 0.47 μM, and 41.7 ± 0.71 μM, respectively, whereas compound 4 exhibited cytotoxicity against Hela and BEL-7042 cell lines with IC50 values of 14.9 ± 0.21 μM and 26.7 ± 1.1 μM, respectively. In addition, compounds 4 and 5 displayed inhibitory activity against α-glycosidase, with IC50 values of 78.2 ± 2.1 μM and 49.3 ± 10.6 μM, respectively. [ABSTRACT FROM AUTHOR]

Four picrotoxane-type sesquiterpenes, dendroterpene A-D ( 1 - 4 ), together with four known compounds ( 5 - 8 ), were isolated from the stems of Dendrobium nobile Lindl. Their structures were elucidated by spectroscopic analysis, X-ray diffraction analysis, analysis of the ECD data according to the Klyne's lactone sector rule, and quantum ECD calculation. Compounds 1 and 2 are two new picrotoxane-type sesquiterpenes with a new carbon skeleton containing a formamide group, which may be derived from the previously reported dendrobiumane B skeleton by the C(9)-C(11) carbon bond cleavage. Compounds 3 , 5 , 6 , and 8 exhibited inhibitory activity against α-glycosidase. Compounds 5 and 6 were cytotoxic against SGC-7901, K562, A549, BEL-7402, and Hela cell lines., (Copyright © 2019 Wang, Chen, Wang, Huang, Cai, Yuan, Zhu, Xu, Mei and Dai.)

Two new succinimide-containing derivatives, cladosporitins A ( 1 ) and B ( 2 ), were isolated from the fermentation cultures of the mangrove-derived fungus Cladosporium sp. HNWSW-1, along with a new pyrone, clapone ( 3 ), as well as the previously reported talaroconvolutin A ( 4 ) and anthraquinone ( 5 ). The structures of the isolated compounds were elucidated by 1D, 2D NMR, and HRMS spectral analysis. Compound 2 showed cytotoxicity against BEL-7042, K562 and SGC-7901 cell lines with IC 50 values of 29.4 ± 0.35 μM, 25.6 ± 0.47 μM, and 41.7 ± 0.71 μM, respectively, whereas compound 4 exhibited cytotoxicity against Hela and BEL-7042 cell lines with IC 50 values of 14.9 ± 0.21 μM and 26.7 ± 1.1 μM, respectively. In addition, compounds 4 and 5 displayed inhibitory activity against α-glycosidase, with IC 50 values of 78.2 ± 2.1 μM and 49.3 ± 10.6 μM, respectively.