title: Bioassay-guided isolation of anti-inflammatory and antinociceptive compound from Plumbago zeylanica leaf.
abstract: Plumbago zeylanica Linn. (Plumbaginaceae) is used in the treatment of various inflammatory ailments in traditional medicines. In order to validate these ethnobotanical practices, the anti-inflammatory and antinociceptive activities of various leaf extracts (petroleum ether (60-80 degrees ), chloroform, acetone, ethanol, and aqueous) were studied using in vivo experimental models at two dose levels (200 and 400 mg/kg, p.o.). Anti-inflammatory activity was tested using the carrageenan induced rat hind paw edema method while analgesic activity was studied using the hot plate and formalin induced models. Diclofenac (100 mg/ kg) was used as the reference standard in both anti-inflammatory and analgesic models and morphine (10 mg/ kg, i.p.) was used as the reference standard in the formalin induced analgesic model. The acetone extract significantly (p < 0.01) reduced inflammation in the rats when compared to the control group. As for the analgesia effect, the acetone and petroleum ether extracts significantly (p < 0.01) decreased the pain stimulus only in the later phase of the formalin test, suggesting that the drug could be peripherally acting. Bioassay-guided fractionation of the acetone extract led to the isolation and identification of plumbagin. Structure elucidation of plumbagin confirmed it as 5-hydroxy-2-methyl-1,4-naphthoquinone, a naphthaquinone derivative, through spectral techniques.
authors.affiliation: Department of Herbal Drug Research, B. R. Nahata College of Pharmacy and Research Center, Mandsaur, Madhya Pradesh, India. sheejapharm@rediffmail.com
authors.forename: E
authors.initials: E
authors.lastname: Sheeja
authors.forename: S B
authors.initials: SB
authors.lastname: Joshi
authors.forename: D C
authors.initials: DC
authors.lastname: Jain
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000302:isolation & purification* / Q000627:therapeutic use / Q000633:toxicity; D001681:Biological Assay; D004195:Disease Models, Animal; D004487:Edema / Q000188:drug therapy*; D005260:Female; D008297:Male; D051379:Mice; D010146:Pain / Q000188:drug therapy*; D010936:Plant Extracts / Q000302:isolation & purification* / Q000627:therapeutic use / Q000633:toxicity; D018515:Plant Leaves / Q000737:chemistry; D029606:Plumbaginaceae / Q000737:chemistry*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D010936:Plant Extracts