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Guilin Chen - One of the best experts on this subject based on the ideXlab platform.

  • rapid screening for α glucosidase inhibitors from Gymnema sylvestre by affinity ultrafiltration hplc ms
    Frontiers in Pharmacology, 2017
    Co-Authors: Guilin Chen
    Abstract:

    Gymnema sylvestre R. Br. (Asclepiadaceae) has been known to posses potential anti-diabetic activity, and the gymnemic acids were reported as the main bioactive components in this plant specie. However, the specific components responsible for the hypoglycemic effect still remain unknown. In the present study, the in vitro study revealed that the extract of Gymnema sylvestre exhibited significant inhibitory activity against α-glucosidase with IC50 at 68.70 ± 1.22 μg/mL compared to acarbose (positive control) at 59.03 ± 2.30 μg/mL, which further indicated the potential anti-diabetic activity. To this end, a method based on affinity ultrafiltration coupled with liquid chromatography mass spectrometry (UF-HPLC-MS) was established to rapidly screen and identify the α-glucosidase inhibitors from Gymnema sylvestre. In this way, nine compounds with higher enrichment factors (EFs) were identified according to their MS/MS spectra. Finally, the structure-activity relationships revealed that glycosylation could decrease the potential antisweet activity of sapogenins, and other components except gymnemic acids in G. sylvestre could also be good α-glucosidase inhibitors due to their synergistic effects. Taken together, the proposed method combing α-glucosidase and UF-HPLC-MS presents high efficiency for rapidly screening and identifying potential inhibitors of α-glucosidase from complex natural products, and could be further explored as a valuable high-throughput screening (HTS) platform in the early anti-diabetic drug discovery stage.

  • Rapid Screening for α-Glucosidase Inhibitors from Gymnema sylvestre by Affinity Ultrafiltration–HPLC-MS
    Frontiers in Pharmacology, 2017
    Co-Authors: Guilin Chen
    Abstract:

    Gymnema sylvestre R. Br. (Asclepiadaceae) has been known to posses potential anti-diabetic activity, and the gymnemic acids were reported as the main bioactive components in this plant specie. However, the specific components responsible for the hypoglycemic effect still remain unknown. In the present study, the in vitro study revealed that the extract of Gymnema sylvestre exhibited significant inhibitory activity against α-glucosidase with IC50 at 68.70 ± 1.22 μg/mL compared to acarbose (positive control) at 59.03 ± 2.30 μg/mL, which further indicated the potential anti-diabetic activity. To this end, a method based on affinity ultrafiltration coupled with liquid chromatography mass spectrometry (UF-HPLC-MS) was established to rapidly screen and identify the α-glucosidase inhibitors from Gymnema sylvestre. In this way, nine compounds with higher enrichment factors (EFs) were identified according to their MS/MS spectra. Finally, the structure-activity relationships revealed that glycosylation could decrease the potential antisweet activity of sapogenins, and other components except gymnemic acids in G. sylvestre could also be good α-glucosidase inhibitors due to their synergistic effects. Taken together, the proposed method combing α-glucosidase and UF-HPLC-MS presents high efficiency for rapidly screening and identifying potential inhibitors of α-glucosidase from complex natural products, and could be further explored as a valuable high-throughput screening (HTS) platform in the early anti-diabetic drug discovery stage.

Aarrthy M Arunachalam - One of the best experts on this subject based on the ideXlab platform.

Shouxun Zhao - One of the best experts on this subject based on the ideXlab platform.

  • two new flavonol glycosides from Gymnema sylvestre and euphorbia ebracteolata
    Carbohydrate Research, 2004
    Co-Authors: Wencai Ye, Biao Yu, Shouxun Zhao, Houming Wu
    Abstract:

    Abstract Two new flavonol glycosides, namely kaempferol 3- O -β- d -glucopyranosyl-(1 → 4)-α- l -rhamnopyranosyl-(1 → 6)-β- d -galactopyranoside ( 1 ) and quercetin 3- O -6″-(3-hydroxyl-3-methylglutaryl)-β- d -glucopyranoside ( 2 ), have been isolated from the aerial parts of Gymnema sylvestre and Euphorbia ebracteolata , respectively. Their structures were determined on the basis of chemical and spectroscopic methods.

  • antisweet saponins from Gymnema sylvestre
    Journal of Natural Products, 2001
    Co-Authors: Wencai Ye, Qingwen Zhang, Shouxun Zhao
    Abstract:

    Three new oleanane-type triterpene glycosides (1−3), along with the sodium salt of alternoside II (4), were isolated from an ethanol extract of the leaves of Gymnema sylvestre. The structures of these new saponins were identified as 21β-O-benzoylsitakisogenin 3-O-β-d-glucopyranosyl(1→3)-β-d-glucuronopyranoside (1), the potassium salt of longispinogenin 3-O-β-d-glucopyranosyl(1→3)-β-d-glucuronopyranoside (2), and the potassium salt of 29-hydroxylongispinogenin 3-O-β-d-glucopyranosyl(1→3)-β-d-glucuronopyranoside (3). The aglycon of 3, Gymnemagenol (3a), was characterized as 3β,16β,28,29-tetrahydroxyolean-12-ene. Structure elucidation was accomplished by interpretation of NMR (DQF-COSY, HMQC, and HMBC) results, FABMS, and hydrolysis. Saponin 1 and the sodium salt of alternoside II (4) exhibited antisweet activity.

  • oleanane saponins from Gymnema sylvestre
    Phytochemistry, 2000
    Co-Authors: Wencai Ye, Qingwen Zhang, Shouxun Zhao
    Abstract:

    Abstract Six oleanane-type saponins, along with two known triterpene saponins, were isolated from the leaves of Gymnema sylvestre . The structures of the oleanane triterpene glycosides were characterized as longispinogenin 3- O -β- D -glucuronopyranoside, 21β-benzoylsitakisogenin 3- O -β- D -glucuronopyranoside, 3- O -β- D -glucopyranosyl(1→6)-β- D -glucopyranosyl oleanolic acid 28- O -β- D -glucopyranosyl ester, oleanolic acid 3- O -β- D -xylopyranosyl(1→6)-β- D -glucopyranosyl(1→6)-β- D -glucopyranoside, 3- O -β- D -xylopyranosyl(1→6)-β- D -glucopyranosyl(1→6)-β- D -glucopyranosyl oleanolic acid 28- O -β- D -glucopyranosyl ester and 3- O -β- D -glucopyranosyl(1→6)-β- D -glucopyranosyl oleanolic acid 28-β- D -glucopyranosyl(1→6)-β- D -glucopyranosyl ester on the basis of hydrolysis and spectral evidence, including 1D- and 2D-NMR (TOCSY, ROESY, HMQC and HMBC) and FABMS analyses.

Wencai Ye - One of the best experts on this subject based on the ideXlab platform.

  • two new flavonol glycosides from Gymnema sylvestre and euphorbia ebracteolata
    Carbohydrate Research, 2004
    Co-Authors: Wencai Ye, Biao Yu, Shouxun Zhao, Houming Wu
    Abstract:

    Abstract Two new flavonol glycosides, namely kaempferol 3- O -β- d -glucopyranosyl-(1 → 4)-α- l -rhamnopyranosyl-(1 → 6)-β- d -galactopyranoside ( 1 ) and quercetin 3- O -6″-(3-hydroxyl-3-methylglutaryl)-β- d -glucopyranoside ( 2 ), have been isolated from the aerial parts of Gymnema sylvestre and Euphorbia ebracteolata , respectively. Their structures were determined on the basis of chemical and spectroscopic methods.

  • antisweet saponins from Gymnema sylvestre
    Journal of Natural Products, 2001
    Co-Authors: Wencai Ye, Qingwen Zhang, Shouxun Zhao
    Abstract:

    Three new oleanane-type triterpene glycosides (1−3), along with the sodium salt of alternoside II (4), were isolated from an ethanol extract of the leaves of Gymnema sylvestre. The structures of these new saponins were identified as 21β-O-benzoylsitakisogenin 3-O-β-d-glucopyranosyl(1→3)-β-d-glucuronopyranoside (1), the potassium salt of longispinogenin 3-O-β-d-glucopyranosyl(1→3)-β-d-glucuronopyranoside (2), and the potassium salt of 29-hydroxylongispinogenin 3-O-β-d-glucopyranosyl(1→3)-β-d-glucuronopyranoside (3). The aglycon of 3, Gymnemagenol (3a), was characterized as 3β,16β,28,29-tetrahydroxyolean-12-ene. Structure elucidation was accomplished by interpretation of NMR (DQF-COSY, HMQC, and HMBC) results, FABMS, and hydrolysis. Saponin 1 and the sodium salt of alternoside II (4) exhibited antisweet activity.

  • oleanane saponins from Gymnema sylvestre
    Phytochemistry, 2000
    Co-Authors: Wencai Ye, Qingwen Zhang, Shouxun Zhao
    Abstract:

    Abstract Six oleanane-type saponins, along with two known triterpene saponins, were isolated from the leaves of Gymnema sylvestre . The structures of the oleanane triterpene glycosides were characterized as longispinogenin 3- O -β- D -glucuronopyranoside, 21β-benzoylsitakisogenin 3- O -β- D -glucuronopyranoside, 3- O -β- D -glucopyranosyl(1→6)-β- D -glucopyranosyl oleanolic acid 28- O -β- D -glucopyranosyl ester, oleanolic acid 3- O -β- D -xylopyranosyl(1→6)-β- D -glucopyranosyl(1→6)-β- D -glucopyranoside, 3- O -β- D -xylopyranosyl(1→6)-β- D -glucopyranosyl(1→6)-β- D -glucopyranosyl oleanolic acid 28- O -β- D -glucopyranosyl ester and 3- O -β- D -glucopyranosyl(1→6)-β- D -glucopyranosyl oleanolic acid 28-β- D -glucopyranosyl(1→6)-β- D -glucopyranosyl ester on the basis of hydrolysis and spectral evidence, including 1D- and 2D-NMR (TOCSY, ROESY, HMQC and HMBC) and FABMS analyses.

Kantha D Arunachalam - One of the best experts on this subject based on the ideXlab platform.