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Propolis was extracted by several organic solvents, and the antioxidative effect of the extracts on palm oil and lard was tested with the extract solely or combined with some synergists, using the Rancimat Method. The extraction yields of propolis by each solvent were 68.1% (75% ethanol), 75.5% (99% ethanol), 67.4% (methanol;, 86.7% (chloroform), 72.6% (ethyl acetate) and 65.6% (butanol). AI (Antioxidative Index; induction period of oil containing antioxidant/induction period of natural oil) of the methanol extract was highest, and more effective on lard than palm oil. The ethyl acetate fraction of 75% ethanol extract showed higher antioxidative effect than 75% ethanol extract, and obtained the highest antioxidative effect on palm oil with ascorbic acid as synergist and lard with δtocopherol
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