African Journal of

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12254

Full Length Research Paper

Toxicological evaluation of precocene II isolated from Ageratum conyzoides L. (Asteraceae) in Sprague Dawley rats

Abiodun Humphrey Adebayo1,2*, Guang Zhi Zeng1, Yu Mei Zhang1, Chang Jiu Ji1, Afolabi Akintunde Akindahunsi3 and Ning Hua Tan1*
1State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China. 2Department of Biological Sciences, College of Science and Technology, Covenant University, PMB 1023, Ota, Ogun State, Nigeria. 3Department of Biochemistry, Federal University of Technology, Akure, Nigeria.
Email: [email protected], [email protected]

  •  Accepted: 15 January 2010
  •  Published: 17 May 2010


 Precocene II (6,7-dimethoxy-2,2-dimethyl-2-chromene) was the main constituent isolated from Ageratum conyzoides L. and reportedly possessed antifungal activity. The study investigated the isolation, purification and toxicological effects of precocene II from A. conyzoides in Sprague Dawley rats. Precocene II was isolated from the petroleum ether fraction of the plant and the structure was determined by1H-,13C-,DEPT-NMR and MS spectral techniques. Three groups of eight rats per group were used for the study. While groups B and C were respectively administered with 25 and 50 mg/kg of precocene II in 0.25% CMC-Na for 11 days by gastric intubation, group A was administered with 0.25% CMC-Na and served as the control group. After the last treatment, animals were fasted overnight and on the 12th day, they were injected intravenously with 0.2 ml/kg body weight of phenobarbital. Animals were subsequently dissected from the abdominal region; blood was collected from the pulmonary vein into EDTA anti-coagulated and non anti-coagulated tubes.  The liver, kidney and spleen tissues were extracted into separate bottles for histopathological examinations. Results from hematological study indicated that the white blood cell (WBC), red blood cell (RBC), plateletcrit (PCT) and mean corpuscular hemoglobin count (MCHC) were significantly higher across the treated groups. Biochemical result showed that serum glucose level was significantly reduced in the treated groups. No apparent damage was noticed in the liver, kidney and spleen tissues. The result therefore suggests that precocene II possesses hypoglycemic property and could alter some hematopoietic elements but was not toxic to the liver, kidney and spleen tissues.


Key words: Ageratum conyzoides, precocene II, isolation, toxicological studies, hematological markers, hypoglycemic property