摘要:采用單因素試驗研究了提取液pH、溫度、液固比和浸提時間對水飛薊子脫脂粉末可溶性蛋白質(zhì)提取率的影響。根據(jù)單因素試驗結(jié)果,應(yīng)用Box-Behnken中心組合試驗設(shè)計原理,選取提取液pH(7.0、8.0和9.0)、溫度(30、40和50 ℃)、液固比(40∶1、50∶1和60∶1,V/m,mL∶g)和浸提時間(90、120和150 min)4個因素為自變量,以水飛薊子脫脂粉末可溶性蛋白提取率為響應(yīng)值,建立回歸模型,該模型相關(guān)系數(shù)R為0.843 2。響應(yīng)面法優(yōu)化提取工藝,得到的最佳提取條件為提取液pH 9.0,溫度50 ℃,液固比60∶1,浸提時間90 min。在此條件下,水飛薊子脫脂粉末可溶性蛋白質(zhì)提取率達(dá)到最大預(yù)測值57.10%。方差分析表明,提取液pH、溫度和液固比對蛋白質(zhì)提取率有顯著影響,而提取時間的影響不顯著。驗證試驗進(jìn)一步證實(shí)了模型和試驗結(jié)果的可靠性。
關(guān)鍵詞:水飛薊子;可溶性蛋白質(zhì);提取工藝;響應(yīng)面法;優(yōu)化
中圖分類號:Q949.783.5;Q946.1;R284.2 文獻(xiàn)標(biāo)識碼:A 文章編號:0439-8114(2011)20-4250-03
Optimization of Soluble Protein Extraction from Milk Thistle (Silybum marianum) Seed by Response Surface Methodology
LIU He-sheng,HU Rui-bin,QI Xiang-yang
(College of Biological & Environmental Science,Zhejiang Wanli University,Ningbo 315100,Zhejiang,China)
Abstract: The effects of pH, temperature, liquid-solid ratio and extraction time on soluble protein extraction from defatted milk thistle [Silybum marianum(L.)] seed were studied by single factor experiments. Using pH (7.0, 8.0 and 9.0), temperature (30, 40 and 50 ℃), liquid-solid ratio (40, 50 and 60 mL/g) and extraction time (90, 120 and 150 min) as independent variables and yield of soluble protein from defatted milk thistle seed as response value, regression model was built through Box-Behnken central composite design, of which the relative coefficient was 84.32%. According to response surface methodology(RSM) applied to optimize the extraction craft, the highest extraction rate which was prognosed as 57.10% could be obtained when pH, temperature, liquid-solid ratio and extraction time was 8.97, 50 ℃, 60 mL/g and 90 min, respectively. Analysis of variance (ANOVA) showed that pH, temperature and liquid-solid ratio had significant effect on extraction rate of soluble protein while extraction time had not. Confirmation tests were employed and validated reliability of the model and experimental results.
Key words: milk thistle(Silybum marianum) seed; soluble protein; extraction technology; response surface methodology; optimization
水飛薊[Silybum marianum(L.)Gaertner],又稱乳薊,為一年或兩年生菊科草本植物,原產(chǎn)于地中海、歐洲西南部,在歐洲和北美已有百年的種植歷史。20世紀(jì)70年代從德國引進(jìn)后,現(xiàn)主要集中在我國的陜西、黑龍江、河北等地。水飛薊是一種治療各種肝病和心血管疾病的傳統(tǒng)藥物,其主要活性成分為黃酮類化合物——水飛薊素,廣泛應(yīng)用于治療各種肝病,例如肝炎、肝硬化、肝癌等[1-3]。此外,水飛薊還可作為抗氧化劑、抗癌劑、消炎劑和毒蕈中毒解毒劑等[4-6]。
水飛薊子除了具有很高的藥用價值以外,還具有多種營養(yǎng)成分,如水飛薊子中含有約29%的油脂,不飽和脂肪酸(油酸、亞油酸和亞麻酸)的比例為71%~80%,可用于防治高血脂、動脈粥樣硬化等心血管疾病[7-9];……