冠突散囊菌与茶叶生物碱共培养液态发酵体系的构建及特性

选取茶叶中三种主要生物碱咖啡碱(Caffeine)、可可碱(Theobromine)、茶碱(Theophylline)作为构建单体-冠突散囊菌共培养液态发酵体系(10 d)的添加底物,考察了冠突散囊菌对茶叶中主要生物碱的发酵特性。结果表明,与对照组相比,咖啡碱(0.2mg/mL)的添加可刺激冠突散囊菌的生长与繁殖,发酵液中葡萄糖的含量下降更为迅速,pH值随着发酵时间的增加持续下降直至第9 d趋于稳定,可溶性蛋白含量呈现先增加后下降的趋势,但在发酵过程中,冠突散囊菌既不能将其作为碳源、氮源消耗来维持生长,也不能代谢分解咖啡碱;可可碱与茶碱(0.08 mg/mL)在发酵体系中的发酵情况与咖啡碱基本相似,两者均能刺激冠突散囊菌的生长与繁殖,但均不能将其作为碳、氮源消耗,且发酵结束后在各自发酵体系中分别检测到0.00091 mg/mL、0.00109 mg/mL的咖啡碱,这说明冠突散囊菌可能具有以可可碱、茶碱作为前体合成咖啡碱的能力。

Construction and Characteristics of the Liquid Fermentation System Co-cultured by Eurotium cristatum and Alkaloids in Tea

Using three representative compounds in tea (caffeine, theobromine and theophylline) as substates to construct a liquid fermentation system of Eurotium cristatum (E.C), the fermentation characteristics of E. C. were preliminarily investigated. Results indicated that the addition of caffeine (0.2 mg/mL) could stimulate the growth of E.C to a certain extent. The content of glucose in the fermentation liquor decreased rapidly, and the pH value progressively declined with the increase of fermentation time until the ninth day, while the content of soluble protein increased first and then decreased. During the fermentation, E.C could not consume the soluble protein as carbon or nitrogen source to maintain its growth, and metabolize caffeine. Similar to caffeine, the theobromine and theophylline (0.08 mg/mL) could also stimulate the growth of Eurotium cristatum to some extent, but could not be consumed as a carbon source. However, the caffeine with concentrations of 0.00091 and 0.00109 mg/mL was detected respectively in the fermentation broth of theobromine and the theophylline, implying that Eurotium cristatum had the ability to synthesize caffeine with precursor of theobromine and theophylline.