Thesis (M.Eng.)--Chulalongkorn University, 2007

This study investigated the use of microwave-assisted solvent extraction of anti-cancer damnacanthal from root of Morinda citrifolia. The effects of materials size, irradiation time and temperature extraction, types of solvents, ethanol composition, and ratio of liquid to sample on the percent recoveries of the extract were determined. The extraction recovery of the extract was compared with conventional methods including ultrasound and subcritical water extraction. In the study, the percent recovery of damnacanthal was found to be significantly higher for the small particle size material. At 80 C, the percent recovery was lower than that obtained at 60 C due to the decomposition of the compound. The highest recovery obtained at high temperatures of 100 and 120 C was obtained after 5 minute extraction, after which the percent recovery decreased, due to the decomposition of the compound. Of all the solvent tested (acetone, acetonitrile, methanol, and ethanol), acetone gave the highest recovery. Moreover, use of ethanol-water solution as extraction solvent increased the yield of damnacanthal due to the swelling of plant tissue matrix by water and suitable polarity of the mixture, and the appropriate ratio of liquid to sample was found to be 100. When compared with other conventional extraction methods such as soxhlet extraction, ultrasound-assisted extraction, and subcritical water extraction, microwave assisted extraction was more efficient as it required shorter time to achieve the same recovery