西兰花副产物中萝卜硫素提取、纯化及鉴定

以西兰花副产物为原料,研究萝卜硫素酶解浸提工艺,并通过单因素试验和响应面试验优化最佳工艺条件。在最佳条件的基础上进行放大实验,通过半制备高效液相色谱纯化和富集萝卜硫素,并应用超高效液相色谱-质谱联用技术对纯化物进行鉴定。结果表明:萝卜硫素最佳提取条件为酶解pH 5.0、酶解温度35℃、酶解时间67 min;在此条件下,萝卜硫素提取量为151.39μg/g,与预测值(156.33μg/g)无显著差异;纯化和富集后,得到28.62 mg/200 g萝卜硫素,回收率为94.52%,纯度为80.74%。根据萝卜硫素的二级质谱与碎片离子信息,进一步确定该纯化物为萝卜硫素。

Extraction,Purification and Identification of Sulforaphane from Broccoli Byproducts

The enzymatic extraction of sulforaphane from broccoli stems and leaves was optimized by one-factor-at-a-time method and response surface methodology. Scale-up experiments were carried out under optimized conditions, and the crude extract was purified by preparative high performance liquid chromatography (HPLC) and identified by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). The results showed that the optimal extrac tion conditions were determined as follows: pH 5.0, temperature 35 ℃ and time 67 min. Under these conditions, the maximum yield of sulforaphane of 151.39 μg/g (on a dry matter basis) was obtained, which agreed with the predicted value (156.33 μg/g). The yield of purified sulforaphane was 28.62 mg from 200 g of broccoli powder, with a 94.52% recovery and 80.74% purity. The tandem mass spectrum and fragment ion information confirmed the substance as sulforaphane.