草莓和蓝莓果实花青素提取及定量方法的比较

 本研究旨在比较果实花青素提取液的提取效果以及花青素分析方法的准确性。用丙酮-水-甲酸（A）、乙腈-乙酸（B）、乙醇-水-乙酸（C）、甲醇-水-乙酸（D）以及含有盐酸的甲醇（E） 等5种提取液分别提取了草莓和蓝莓果实中的花青素，用比色法和液相色谱法分别测定了花青素的含量。试验结果表明：由于提取液中有机溶剂和酸种类的不同，提取效果差异甚大。提取草莓花青素时，以D的提取效果最好，其次是E、C、A，B的提取量最低，还不到D的1/3。提取蓝莓花青素得到的结果与草莓相似。用比色法分析，D、E、C提取液提取的草莓和蓝莓果实的花青素含量明显低于液相色谱分析的结果， 但B提取液比液相色谱结果高2倍以上，A提取液提取蓝莓时比色法与液相色谱法的结果相近，而提取草莓时比色法比液相色谱结果高出约50%。建议花青素的定量方法应尽量使用液相色谱法，对同一种果实，尤其是以低沸点醇类作提取液时可以用比色法。

Comparisons of Extraction Solvents and Quantitative-methods for Analysis of Anthocyanins in Strawberry and Blueberry Fruits

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.