黏质沙雷氏菌产红色素的理化性质及抗氧化活性研究

Studies on physicochemical properties and antioxidant activity of red pigment produced by Serratia marcescens

为了探索黏质沙雷氏菌所产的天然红色素应用于食品、药品和印染等领域的可能性,对该色素的光谱特性、溶解性、稳定性和抗氧化活性进行了实验研究。结果表明:该色素的最大吸收波长为500nm;色素易溶于水,且易溶于乙醇、乙酸乙酯、丙酮、甲醇和四氢呋喃,微溶于二氯甲烷和氯仿;随着自然光照射时间的增加以及温度的升高红色素的稳定性逐渐降低;色素在pH中性条件下稳定,弱酸条件对色素有一定的增色效果,在碱性条件下随着pH的增大色素稳定性逐渐降低;山梨酸钾、抗坏血酸、蔗糖、柠檬酸、氯化钠、磷酸二氢钠对红色素有不同程度的消色作用;金属离子Mg^(2+)、Zn^(2+)、Ca^(2+)对色素稳定性影响较小,Al^(3+)、Cu^(2+)、Fe^(3+)对色素稳定性影响较大;红色素对DPPH自由基、羟自由基、ABTS自由基均具有清除能力,表明该色素具有一定的抗氧化作用,但均弱于抗坏血酸。

In order to explore the possibility of using the natural red pigment produced by Serratia marcescens in food,medicine,printing and dyeing,the spectral characteristics,solubility,stability and antioxidant activity of the pigment were studied. The results showed that maximum absorption wavelength of the pigment was 500 nm. The pigment is easily soluble in water,ethanol,ethyl acetate,acetone,methanol and tetrahydrofuran,and slightly soluble in dichloromethane and chloroform. The stability of red pigment decreased with the increase of natural light irradiation time and temperature. The pigment is stable under neutral pH,and has coloring enhance effect under a weak acid. Under alkaline conditions,pigment stability decreases gradually with the increase of pH. Potassium sorbate,ascorbic acid,sucrose,citric acid,sodium chloride and sodium dihydrogen phosphate had different achromatic effects on the pigment. Metal ions Mg^(2+),Zn^(2+) and Ca^(2+) have little effect on the stability,while Al^(3+),Cu^(2+) and Fe^(3+) have great effect on the stability of pigment. The pigment has scavenge ability on DPPH radical,hydroxyl radical and ABTS radical,which indicating it has certain antioxidant effect,but is not as strong as ascorbic acid.