绿色木霉菌T-YY黄色素的稳定性研究

Stability of yellow pigment from Trichoderma viride strain T-YY

为开发一种新型的、功能性天然食品添加剂,该文以绿色木霉菌T-YY发酵液冻干粉(色素粗品)为试验材料,初步研究其紫外-可见光谱性质与稳定性。结果表明,色素粗品中至少含有4种以上不同性质的黄色素,该黄色素易溶于水和醇,色价高,在紫外区及可见光区各有一个吸收峰,最大吸收波长分别为286.5 nm和380 nm;在酸碱环境中色调保持亮黄色,其水溶液在pH<5.0时出现浑浊,在pH≥5.0时呈亮黄色;pH值3.0～9.0色素溶液在室内自然光(25℃)下放置7 d后色调稳定;热稳定性好,100℃加热30 min色素保留率达到90.2%;抗H2O2、HNO3氧化能力强,但不耐Na2SO3还原作用。Fe3+、Cu2+和Mn2+的对色素具有消褪作用,Fe2+、Mg2+、Zn2+、Ca2+、K+、Na+则对其有不同程度的保护和增色作用。试验表明,绿色木霉T-YY黄色素在稳定性上呈现出一定优势,因此具有较大的开发潜力。

In order to develop a new and functional natural food additives, crude pigment obtained from the fermentation liquid of Trichoderma viride T-YY was treated with vacuum freeze-drying technology and its ultraviolet-visible spectroscopic properties and stability were studied. The results show that at least four kinds of yellow pigments with different properties are found in the crude pigment. The yellow pigments are easy to dissolve in water and methanol and the colour values are high. Each has one absorption peak of yellow pigments in ultraviolet range and visible range and the maximum absorption wavelength were 286.5 nm and 380 nm, respectively. The colour of the yellow pigments retains a good hue of bright yellow in far-ranging ofpH value, the aqueous solution gets turbid when pH〈5.0 and retains bright yellow when pHi〉5.0. It is relatively stable to light indoor when the pH value from 3.0 to 9.0 and heated at 100℃for a short time. The antioxidation ability to I-I202 and HNO3 is strong but it is sensitive to reductant. Fe^3＋、 Cu^2＋ and Mn^2＋ can fade the colour of the yellow pigment, but Fe^2＋、 Mg^2＋、 Zn^2＋、 Ca^2＋、 K^＋、 Na^＋ have a good protective effect on it. In a word, the yellow pigment from Trichoderma viride T-YY is worth to develop for its high stability.