萝卜籽蛋白提取物对鲟鱼腐败菌抑制作用及其理化性质的研究

本实验旨在探究萝卜籽蛋白提取物作为水产品保鲜剂的应用潜力。研究了萝卜籽蛋白提取物对28 株鲟鱼 腐败菌的生长抑制作用，并探究了该蛋白提取物对温度、pH值、紫外线、金属离子、表面活性剂和蛋白酶的稳 定性。结果表明：萝卜籽蛋白提取物对8 株气单胞菌、7 株假单胞菌、11 株肠杆菌和2 株其他菌属的菌株均有抑 制作用；经80 ℃处理30 min的萝卜籽蛋白提取物相对抑菌活力大于79.00%；萝卜籽蛋白提取物在pH 2.0～8.0的 不同条件下处理2 h，相对抑菌活力大于72.00%；紫外线照射0～24 h后萝卜籽蛋白提取物相对抑菌活力均大于 94.00%；萝卜籽蛋白提取物对Ag＋敏感，但对Pb3＋、Mg2＋、Li＋等13 种金属离子稳定性较好；其对表面活性剂 尿素、吐温20和司班80稳定性较好；经不同质量浓度的胰蛋白酶、木瓜蛋白酶、蛋白酶K和中性蛋白酶分别处理 后，其相对抑菌活力均大于96.00%。萝卜籽蛋白提取物对鲟鱼腐败菌具有较好的抑制作用，且该蛋白提取物对 热处理、酸处理、紫外线照射、蛋白酶、表面活性剂和金属离子处理均具有一定的稳定性，因此具有开发成新型 水产品保鲜剂的潜力。

Inhibition of Sturgeon Spoilage Bacteria by Protein Extract from Radish Seed and Its Physicochemical Characteristics

The objective of this paper was to evaluate the potential of radish seed protein extract (RSPE) for use as an aquatic product preservative. The bacteriostatic effect of RSPE against 28 strains of sturgeon spoilage bacteria was investigated and its stability against heating, pH, ultraviolet (UV) irradiation, metal ions, surfactants and proteases was evaluated as well. RSPE was shown to inhibit 8 Aeromonas, 7 Pseudomonas, 11 Enterobacteriaceae and 2 other strains isolated from spoiled sturgeon. RSPE remained over 79.00%, 72.00% and 94.00% of its original antimicrobial activity after 30 min of treatment at 80 ℃, 2 h of treatment at pH 2.0–8.0 and 0–24 h of UV irradiation, respectively. RSPE was sensitive to Ag+ but was insensitive to 13 other metal ions including Pb3+, Mg2+ and Li+. In addition, surfactants such as urea, Tween 20 and Span 80 had little effect on the antimicrobial activity of RSPE. RSPE remained over 96.00% of its original antimicrobial activity after enzymatic treatment with trypsin, papain, neutral protease or proteinase K at different concentrations. It can conclude that RSPE has potent bacteriostatic effect against sturgeon spoilage bacteria and good stability to heat, acid, UV light, proteases, surfactants and metal irons. Thus, it has the potential to be developed as an aquatic product preservative.