不同提取方法对甘薯花青素含量测定的影响

Effects of Different Extraction Methods on Anthocyanin Content Detection in Sweet Potato

不同提取方法影响植物花青素的提取效率及稳定性,进而影响含量的测定。本实验分别采用柠檬酸-磷酸氢二钠缓冲液和1%盐酸分别作为提取剂,对两个紫色甘薯品种“济薯18”和“中泰8号”的鲜薯和薯干干粉进行了花青素的提取,并用不同的紫外-可见分光光度计对其吸光度进行了测定。结果表明:两个甘薯品种花青素含量有显著差异,对同一品种不同的提取方法可显著影响花青素含量的测定;延长提取时间可引起花青素的部分降解,1%盐酸作为提取剂有利于花青素的稳定性;同时,测定仪器的精确度或稳定性对测定结果有一定影响。

Extraction efficiency and stability of plant anthocyanins can be affected by different extraction protocols. In this paper we tested two different extraction buffers, the Na2HPO4-citric acid （pH3.0） and 1% HC1, on the effect of anthoeyanin detection from fresh roots and dried chips of sweet potato cultivar ‘Zhongtai No.8＇ and ‘Jishu 18＇. The anthoeyanin content was calculated based on the ODszs values measured from NanoDrop ND100 and Hekios UV-VIS spectrometers, respectively. Our results shows that the anthocyanin contents of the two cultivars are different and, the extraction method using 1%HC1 was able to detect anthocyanin content higher than that of Na2HPO4-citric acid buffer-based method. Prolonging the extraction time from 2 hours to 7 days did not increase the anthocyanin content and could cause partial degradation, and there is less changes in 1% HC1 than the Na2HPO4-citric acid buffer. The results detected by Nano-Drop spectrometer also showed differences with Hekios spectrometer, possibly due to the accuracy and stability of the two machines.