Polyphenols of Melaleuca quinquenervia leaves--pharmacological studies of grandinin.
Four polyphenolic acid derivatives and three ellagitannins were isolated from the leaves of Melaleuca quinquenervia (Clav.) S. T. Blake for the first time. Their structures were elucidated as gallic acid (1), ellagic acid (2), 3-O-methylellagic acid (3), 3,4,3'-tri-O-methylellagic acid (4), 2,3-O-hexahydroxydiphenoyl-(alpha/beta)-D-(4)C(1)-glucopyranose (5), castalin (6) and grandinin (7) on the basis of chemical, mass spectrometric (-ve ESI-MS) and spectroscopic (UV, (1)H-, (13)C NMR, (1)H,(1)H-, (1)H,(13)C-COSY, (1)H,(1)H-TOCSY and HMBC) analyses. Grandinin (the major compound) showed radical scavenging properties by its reaction with 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical [EC(50) = 4.3 +/- 0.3 micro g mL(-1)]. It was found to be relatively nontoxic in mice [LD(50) = 316 mg Kg(-1) b.wt.]. It exhibited a significant dose-dependent (35-70 mg Kg(-1)) hypoglycemic effect by significantly reducing blood glucose level in basal condition and after heavy glucose load in normal mice. Moreover, it reduced the elevated blood glucose level in STZ-induced diabetic mice. In addition, grandinin reduced the elevated blood urea nitrogen and serum lipid peroxides in STZ-induced diabetic mice.
Moharram
F A
FA
Pharmacognosy Department, Faculty of Pharmacy, Helwan University, Cairo, Egypt.
Marzouk
M S
MS
El-Toumy
S A A
SA
Ahmed
A A E
AA
Aboutabl
E A
EA
D000818:Animals; D001713:Biphenyl Compounds; D001786:Blood Glucose / Q000187:drug effects; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced / Q000517:prevention & control; D004305:Dose-Response Relationship, Drug; D005260:Female; D005419:Flavonoids / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D016166:Free Radical Scavengers / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D005951:Glucose Tolerance Test; D006027:Glycosides / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D006576:Heterocyclic Compounds, 4 or More Rings / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D007928:Lethal Dose 50; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D031650:Melaleuca; D051379:Mice; D010636:Phenols / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D008517:Phytotherapy; D010851:Picrates; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D018515:Plant Leaves; D059808:Polyphenols; D013311:Streptozocin; D017392:Thiobarbituric Acid Reactive Substances; D014508:Urea / Q000097:blood
D001713:Biphenyl Compounds; D001786:Blood Glucose; D005419:Flavonoids; D016166:Free Radical Scavengers; D006027:Glycosides; D006576:Heterocyclic Compounds, 4 or More Rings; D007004:Hypoglycemic Agents; D010636:Phenols; D010851:Picrates; D010936:Plant Extracts; D059808:Polyphenols; D017392:Thiobarbituric Acid Reactive Substances; C479598:grandinin; D013311:Streptozocin; D014508:Urea; C004931:1,1-diphenyl-2-picrylhydrazyl