响应面法优化蒲桃籽中三萜类化合物的提取工艺及其抗氧化活性分析

以蒲桃籽为原料，通过单因素实验考察各因素对蒲桃籽中三萜类化合物得率的影响。运用Design-Expert12软件设计响应面法优化提取工艺，并进行模型诊断和工艺验证。最后对提取得到的蒲桃籽三萜进行DPPH·、ABTS+·清除能力的测定，评价其抗氧化活性。结果表明，蒲桃籽三萜类化合物的最优提取工艺为甲醇体积分数44.30%、料液比1:47.18 g/mL、提取时间101.07 min(实验调整为101 min)。此条件下，实际得率(12.11 mg/g)与理论得率(12.28 mg/g)之间的偏差仅为1.26%(<5%)，误差较小。蒲桃籽三萜类化合物DPPH·、ABTS⁺·清除能力的IC₅₀值分别是为24.93、12.16μg/mL，并且抗氧化活性与其浓度呈现出一定的量效关系。此优化实验有效可行，且蒲桃籽三萜类化合物具有较强的抗氧化活性。本文的研究为蒲桃资源的开发利用提供了一定的理论依据。

Optimization of the Extraction Process of Triterpenoids from the Seeds of Syzygium jambos L. Alston by Response Surface Methodology and Its Antioxidant Activity

In this study the single factor experiments were employed to determine the effects of various factors on extraction rate of triterpenoids in the seeds of S. jambos L. Alston using the yields as indicator. Then Box-Behnken design and response surface methodology were employed to optimize the extraction process using the Design-Expert 12 software. Moreover, the antioxidant activity of triterpenoids in the seeds of S. jambos L. Alston was evaluated by determining the scavenging capacity of DPPH and ABTS free radical. The results showed that the optimal conditions were as follows: Methanol concentration 44.30%, solid-liquid ratio 1:47.18 g/mL, extraction time was 101.07 min (adjusted to 101 min in the experiment). Under these conditions, the deviation between the experimental extraction yield value (12.11 mg/g) and the predicted value (12.28 mg/g) of triterpenoids in the seeds of S. jambos L. Alston was only 1.26% (<5%), and the error was small. The IC₅₀ values of scavenging rates on DPPH and ABTS free radicals were 24.93 and 12.16 μg/mL, respectively. The antioxidant activity showed a certain dose effect relationship with the sample concentration. The results indicated that this optimization test was effective and feasible, and the extracted S. jambos L. Alston triterpenoids had good antioxidant activity in vitro. The present study provides supplement information for the potential use of the seeds of S. jambos L. Alston in food and medicine ingredients.