黑米花色苷的提取及纯化

目的：得到黑米花色苷最佳提取工艺，建立应用大孔吸附树脂纯化花色苷的方法。方法：以矢车菊素-3- 葡萄糖苷为跟踪指标，通过单因素试验和正交试验，对影响黑米花色苷提取的各因素进行研究，比较9 种大孔吸附树脂对花色苷的静态吸附和解吸性能。结果：黑米花色苷最佳提取条件，提取液乙醇- 水- 盐酸体积比为50:50:0.5，温度50℃，固液比为1:10(g/mL)，提取时间为1h，提取次数为3 次。通过对9 种大孔吸附树脂的比较，确定AB-8 为纯化黑米的理想吸附树脂，80% 乙醇为洗脱剂，上样流速为1.0BV/h，解吸流速为2.0BV/h。结论：测定经树脂纯化后提取物中花色苷的含量达到22.59%(粗提物中花色苷含量为3.448%)，树脂富集倍数为 6.02，此工艺条件纯化效果显著。

Extraction and Purification of Anthocyanins from Black Rice

To maximize anthocyanins yield from black rice extracted with ethanol solution, one-factor-at-a-time and orthogonal array design methods were used to examine the optimal values of 5 main technological parameters. Cyanidin-3-glucoside was served as the reference substance for the quantification of anthocyanins. Subsequently, the crude anthocyanin extract obtained was purified by macroporous resin absorption. Results showed that an optimal anthocyanins yield was achieved through extracting the material with a 10-fold (mL/g) volume of a mixture composed of absolute ethanol, water and hydrochloric acid (50: 50:0.5, V/V) for 1 h 3 times each time at 50 ℃. Among 9 macroporous resins tested, AB-8 exhibited the best compromise between high adsorption and high desorption rates so as to be used to purify the crude anthocyanin extract from black rice. In the purification, the optimal elution solvent was 80% aqueous ethanol and the optimal values of flow rate for sample loading onto AB-8 and elution solvent flow rate were 1.0 and 2.0 BV/h, respectively. The purified anthocyanin extract was determined to have 22.59% anthocyanins content (the value in the crude anthocyanin extract 3.448%) with a 6.02-fold enrichment, which demonstrated an effective purification.