OBJECTIVE: It is of great interest to identify the oxidation products of sesamol that may be beneficial to humans. This study was undertaken to identify the oxidation products of sesamol and investigate their antioxidant and cytotoxic activities.

MATERIALS AND METHODS: Using the ferricyanide oxidation approach, four oxidation products of sesamol (2, 3, 20 & 21) have been identified. Structural elucidation of these compounds was established on the basis of their detailed NMR spectroscopic analysis, mass spectrometry and x-ray crystallography. Additionally, a formation mechanism of compound 20 was proposed based on high-resolution mass spectrometry-fragmentation method. The antioxidant activities of these compounds were determined by the DPPH, FRAP, and ABTS assays. The in vitro antiproliferative activity of these compounds was evaluated against a panel of human cancer cell lines as well as non-cancerous cells.

RESULTS: Two oxidation products of sesamol were found to contain an unusual methylenedioxy ring-opening skeleton, as evidenced by spectroscopic and x-ray crystallographic data. Among all compounds, 20 displayed impressive antiproliferative activities against a panel of human cancer cell lines yet remained non-toxic to noncancerous cells. The antioxidant activities of compound 20 are significantly weaker than sesamol as determined by the DPPH, FRAP, and ABTS assays.

MATERIALS AND METHODS: A total of 30 CF-1 albino mice obtained from the animal house of faculty of Medicine, Benghazi University, Benghazi, Libya were included in the study. These mice were fed with high cholesterol diet and divided into 2 groups. Twenty mice were administered piperine at a dose of 5mg/kg body weight. Piperine was isolated in Department of Pharmacognosy, Faculty of Pharmacy, Benghazi University, Benghazi and 10 mice were not administered piperine but fed with high fat diet. These mice were anesthetized with ketamine and halothane and blood was drawn from each mouse before the study and after three weeks by cardiocentesis. Serum transaminases (alanine aminotransferase [ALT] and aspartate aminotransferase [AST]), alkaline phosphatase and total protein were measured by authenticated methods.

RESULTS: Serum alanine amino transferase was significantly elevated (p=0.0002) in group A mice after the administration of Piperine extract for three weeks compared to those of group B mice. Serum aspartate amino transferase was elevated significantly (p=0.046) and alkaline phosphatase (p= 0.0001) also was significantly increased after the administration of piperine. Serum total protein (p= 0.011) values were significantly decreased after the use of piperine for three weeks in group A mice.