斜生栅藻生物转化咖啡渣废弃物的应用研究

Valorization of Spent Coffee Grounds by Scenedesmus obliquus in a Biorefinery Approach

摘要:

咖啡渣（Spent Coffee Grounds, SCG）作为咖啡生产过程中的副产物，其妥善处理对于资源利用及环境保护意义重大。为了探索咖啡渣废弃物的生物处理，该研究选用生长迅速、抗逆性强的淡水微藻——斜生栅藻（Scenedesmus obliquus, FACHB-417）。咖啡渣经过提油、酶水解处理调制成培养基以培养斜生栅藻，实验结果表明，咖啡渣的油脂得率占咖啡渣干重的比例可达12.2 wt.%。与常规培养基（BG11）相比，咖啡渣水解液组（SCG10）中斜生栅藻的生物质积累及碳水化合物相对含量最高分别提升6.38倍和3.09倍。斜生栅藻实现了对咖啡渣中碳源的利用以积累生物质和碳水化合物，还实现了对咖啡因的生物降解，其代谢物1,3,7-三甲基尿酸在SCG10组是BG11组的28.22倍。该研究表明斜生栅藻实现了对咖啡渣的资源化利用并生物降解咖啡因，为咖啡渣的资源化利用并生成藻基营养物质提供了一种经济环保的新途径。

Abstract:

Spent coffee grounds （SCG） are a substantial byproduct of the coffee industry, require proper disposal, which is of great significance for resource utilization and environmental protection. Scenedesmus obliquus （FACHB-417） possessing rapid proliferation capabilities and pronounced stress tolerance was selected to explore the biological treatment of SCG. The SCG were subjected to oil extraction and enzymatic hydrolysis, then prepared to cultivate S. obliquus. The results demonstrated that the oil were extracted from SCG, achieving a yield of 12.2 wt.%. Compared to the control group （BG11）, the biomass accumulation and relative carbohydrate content of S. obliquus in the group of adding hydrolysate spent coffee grounds （SCG10） were enhanced by as much as 6.38 times and 3.09 times, respectively. The utilization of carbon sources in SCG to accumulate biomass and carbohydrate was achieved by S. obliquus. Additionally, the biodegradation of caffeine was achieved, when its metabolite, 1,3,7-trimethyluronic acid, was 28.22 times more abundant in the SCG10 group than in the BG11 group. This study demonstrated that S. obliquus realized the resource utilization of SCG and biodegradation of caffeine, which provided a new economic and environmental friendly way to utilize SCG and generate algal-based nutrients.