关键词: 草莓, 蓝莓, 花青素, 分析方法, 提取液

Abstract: In this study, the extraction efficacity of solvent type and precision of determining-methods for anthocyanins in fruits were compared. Five solvents, acetone:water:formic acid (A), acetonitrile:acetic acid (B), ethanol:water:acetic acid (C), methanol:water:acetic acid (D), and methanol:HCl (E) were used to extract anthocyanins in strawberry and blueberry fruits and the anthocyanin content in the extracts was determined with colorimetry and HPLC. The results showed that extraction efficiency varied among the solvents with different organic-solvent and acid-type. In strawberries, the extraction efficiency of anthocyanin with D was best, followed by E, C, and A. However, B was the worst to extract the anthocyanin, with its value being less than 1/3 that obtained using the extract containing D. A similar tendency was found in blueberries. The anthocyanin contents determined by colorimetry with extracts containing D, E, and C in both fruits were respectively lower than that shown by HPLC. But, the value was obtained by colorimetry with extracts containing B was 2-fold to that by HPLC. In blueberries, obvious differences were not found in the results obtained using the extract containing A employing both methods, although in strawberries the anthocyanin content determined using the spectrophotometric method was higher by about 50% than with those obtained using HPLC. These results suggest that the HPLC method should be utilized to determine the anthocyanin content and that the colorimetry could be used to compare samples from the same kind of fruit, especially, using a low boiling-point alcohol as a solvent.

Key words: strawberry, blueberry, anthocyanin, determination method, extraction solvent