Antihyperglycaemic flavonoids from Syzygium samarangense (Blume) Merr. and Perry.
2',4'-Dihydroxy-3',5'-dimethyl-6'-methoxychalcone 1, its isomeric flavanone 5-O-methyl-4'-desmethoxymatteucinol 2 and 2'4'-dihydroxy-6'-methoxy-3'-methylchalcone 3 were isolated from the leaves of S. samarangense using a bioassay-directed scheme. In an oral glucose tolerance test, at a dosage of 1.0 mg/20 g mouse, 1 and 2 significantly (alpha = 0.05) lowered the blood glucose levels (BGLs) in glucose-hyperglycaemic mice when administered 15 min after a glucose load. When co-administered with glucose, only 1 showed a significant lowering of BGLs 45 min after its oral administration. When administered 15 min before glucose, none of the flavonoids showed a positive effect. Only 1 decreased significantly, at alpha = 0.05, the BGLs of alloxan-diabetic mice at t = 90-150 min.
Resurreccion-Magno
Ma Hanshella C
MH
Institute of Chemistry, University of the Philippines, Diliman, Quezon City, Philippines.
Villaseñor
Irene M
IM
Harada
Nobuyuki
N
Monde
Kenji
K
D000496:Alloxan; D000818:Animals; D001786:Blood Glucose / Q000187:drug effects; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced / Q000517:prevention & control*; D004305:Dose-Response Relationship, Drug; D005419:Flavonoids / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D005951:Glucose Tolerance Test; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D051379:Mice; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D018515:Plant Leaves; D027842:Syzygium
D001786:Blood Glucose; D005419:Flavonoids; D007004:Hypoglycemic Agents; D010936:Plant Extracts; D000496:Alloxan