抄録
A convenient analytical method for diferulic acids (diFAs) in foods was developed. Rice flour (10 g) was stirred in 250 ml of 0.1 N NaOH at room temperature for 50 h. Liberated phenolics were extracted with ethylacetate and analyzed with HPLC. Three major diFAs:(5, 5'-diFA (1), 8-O-4' diFA (2), and 8, 5'-diFA benzofuran form (3)) were quantified. The contents of diFAs determined by this direct liberation method were greater than those determined after cell wall was prepared from rice sample. Contents of diFAs in food samples (27 items) were determined by this method. Seeds or fruits of the monocotyledon plants rice, wheat, Chinese water chestnut, banana, and pineapple contained diFAs (2 (1.9-410 μg/g)> 3 (1.0-390 μg/g)>1 (0.8-180 μg/g)). We did not detect diFAs in edible parts of the monocotyledon plants arrowhead, asparagus, devil's tongue, or taro, or of the dicotyledon plants buckwheat, lotus root, potato, or pumpkin.
