Caffeine, theobromine and theophylline are main purine alkaloid in tea. Theophylline is the downstream metabolite and it remains at a very low level in Camellia sinensis. In our previous study, Aspergillus sydowii could convert caffeine into theophylline in solid-state fermentation of pu-erh tea through N-demethylation. In this study, tea-derived fungi caused theophylline degradation in the solid-state fermentation. The purpose of this study is identify and isolate theophylline-degrading fungi and investigate their application in production of methylxanthines with theophylline as feedstock through microbial conversion. Seven tea-derived fungi were collected and identified by ITS, β-tubulin and calmodulin gene sequences, Aspergillus ustus, Aspergillus tamarii, Aspergillus niger and A. sydowii associated with solid-state fermentation of pu-erh tea have shown ability to degrade theophylline in liquid culture. Particularly, A. ustus and A. tamarii could degrade theophylline highly significantly (p < 0.01). 1,3-dimethyluric acid, 3-methylxanthine, 3-methyluric acid, xanthine and uric acid were detected consecutively by HPLC in A. ustus and A. tamarii, respectively. The data from absolute quantification analysis suggested that 3-methylxanthine and xanthine were the main degraded metabolites in A. ustus and A. tamarii, respectively. 129.48 ± 5.81 mg/L of 3-methylxanthine and 159.11 ± 10.8 mg/L of xanthine were produced by A. ustus and A. tamarii in 300 mg/L of theophylline liquid medium, respectively. For the first time, we confirmed that isolated A. ustus, A. tamarii degrade theophylline through N-demethylation and oxidation. We were able to biologically produce 3-methylxanthine and xanthine efficiently from theophylline through a new microbial synthesis platform with A. ustus and A. tamarii as appropriate starter strains.

中文翻译：

---

茶碱降解曲霉菌的分离，鉴定及应用

咖啡因，可可碱和茶碱是茶中的主要嘌呤生物碱。茶碱是下游的代谢产物，在山茶中含量仍然很低。在我们之前的研究中，通过N-去甲基化，在普sy茶固态发酵中，赛曲霉可以将咖啡因转化为茶碱。在这项研究中，茶源真菌在固态发酵中引起茶碱降解。这项研究的目的是鉴定和分离可降解茶碱的真菌，并研究它们在以茶碱为原料通过微生物转化生产甲基黄嘌呤中的应用。收集了七种茶来源的真菌，并通过ITS，β-微管蛋白和钙调蛋白基因序列，uspergillus ustus，tamarii tamarii，Aspergillus niger和A进行了鉴定。与普-茶固态发酵相关的sydowii已显示出在液体培养物中降解茶碱的能力。特别地，us.usus和ta.tamarii可以显着降解茶碱（p <0.01）。高效液相色谱法分别在us.ustus和tamarii中连续检测到1,3-二甲基尿酸，3-甲基黄嘌呤，3-甲基尿酸，黄嘌呤和尿酸。绝对定量分析的数据表明，3-甲基黄嘌呤和黄嘌呤分别是在us.ustus和ta.mari中的主要降解代谢物。在300 mg / L茶碱液体培养基中，A。ustus和tamarii分别产生129.48±5.81 mg / L的3-甲基黄嘌呤和159.11±10.8 mg / L的黄嘌呤。首次，我们证实了分离的A.ustus，tamarii通过N-去甲基化和氧化降解茶碱。