From the methanol extract of Bauhinia megalandra fresh leaves, eight flavonoids were isolated and evaluated by rat liver microsomal glucose-6-phosphatase (G-6-Pase) bioassay, which might be a useful methodology for screening antihyperglycaemic substances. All the flavonoids assayed showed an inhibitory effect on the intact microsomal G-6-Pase: quercetin and kaempferol exhibited the lowest effect; astilbin, quercetin 3-O-alpha-rhamnoside, kaempferol 3-O-alpha-rhamnoside and quercetin 3-O-alpha-arabinoside an intermediate effect. The highest inhibitory activity was shown by quercetin 3-O-alpha-(2''-galloyl)rhamnoside and kaempferol 3-O-alpha-(2''galloyl)rhamnoside. None of the flavonoids mentioned above showed an inhibitory effect on the disrupted microsomal G-6-Pase. Quercetin 3-O-alpha-(2''-galloyl)rhamnoside and kaempferol 3-O-alpha-(2''-galloyl)rhamnoside exhibited the lowest IC50 of all the flavonoids assayed. Also, the phlorizin IC50 is reported.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/ptr.1703 | DOI Listing |
Fitoterapia
December 2010
Sección de Bioquímica Médica, Instituto de Medicina Experimental, Facultad de Medicina, Universidad Central de Venezuela Apartado Postal 5058, Caracas, Venezuela.
Glucose intestinal absorption (GIA) is one of the factors that increase glycemia. Its reduction could be an important factor in decreasing hyperglycemia in diabetic patients. It has been shown that the aqueous extract of Bauhinia megalandra leaves inhibits GIA.
View Article and Find Full Text PDFPhytother Res
October 2005
Centro de Química Orgánica, Escuela de Química, Facultad de Ciencias, Universidad Central de Venezuela, Apartado postal 47102, Caracas, Venezuela.
From the methanol extract of Bauhinia megalandra fresh leaves, eight flavonoids were isolated and evaluated by rat liver microsomal glucose-6-phosphatase (G-6-Pase) bioassay, which might be a useful methodology for screening antihyperglycaemic substances. All the flavonoids assayed showed an inhibitory effect on the intact microsomal G-6-Pase: quercetin and kaempferol exhibited the lowest effect; astilbin, quercetin 3-O-alpha-rhamnoside, kaempferol 3-O-alpha-rhamnoside and quercetin 3-O-alpha-arabinoside an intermediate effect. The highest inhibitory activity was shown by quercetin 3-O-alpha-(2''-galloyl)rhamnoside and kaempferol 3-O-alpha-(2''galloyl)rhamnoside.
View Article and Find Full Text PDFPhytother Res
July 2005
Sección de Bioquímica Médica, Instituto de Medicina Experimental, Facultad de Medicina, Universidad Central de Venezuela, Caracas, Venezuela.
In intact microsomes, quercetin 3-O-alpha-(2''-galloyl)rhamnoside (QGR) inhibits glucose-6-phosphatase (G-6-Pase) in a concentration-dependent manner. QGR increased the G-6-Pase K(m) for glucose-6-phosphate without change in the V(max). The flavonol did not change the kinetic parameters of disrupted microsomal G-6-Pase or intact or disrupted microsomal G-6-Pase pyrophosphatase (PPase) activity.
View Article and Find Full Text PDFFitoterapia
February 2003
Sección de Bioquímica Médica, Instituto de Medicina Experimental, Facultad de Medicina, Universidad Central de Venezuela, Apartado Postal 50587, Sabana Grande, Caracas, Venezuela.
Aqueous extract of Bauhinia megalandra leaves was able to inhibit the intestinal glucose absorption in a concentration-dependent way and additive to phlorizine. Moreover, B. megalandra leaf extract drastically reduced the 14C-glucose uptake by enterocyte brush border membrane vesicles.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!