Comparison of different slow-release nutrient composites produced to stimulate microorganisms

Abstract Concern for environmental quality has increased in society because industrial and technological development has released high levels of contaminants into the environment, such as hydrocarbons. A technique widely used for bioremediation is biostimulation, which may be enhanced by microencapsulation. This research formulated slow-release nitrogen and phosphorus compounds using different polymer (Alginate/Capsul®, carboxymethyl cellulose) matrices and compared them with the agricultural product Osmocote® and mineral medium Bushnell-Haas as hydrocarbonoclastics biostimulation agents in the environment for pollutant bioremediation. N (nitrogen) and P (phosphorus) were immobilized using lyophilization and ionic gelation techniques. Experiments were conducted using encapsulated material and evaluated for biomass production, glucose consumption as organic carbon source and N and P supply. The immobilized carboxymethyl cellulose compound showed the best results of glycosidic degradation (66.7%) and microbial biostimulation (350 mg L-1 protein) compared to systems containing free nutrients (11.3% and 150 mg L-1 degradation glycosidic and microbial biostimulation, respectively). Thus, this compound is a potential slow release product for bioremediation processes.

摘要 随着工业与科技发展向环境中排放了包括烃类在内的大量污染物，社会对环境质量的关注度日益提升。生物刺激是目前广泛应用于污染物生物修复的技术手段，而微囊包埋技术可进一步强化其修复效能。本研究以不同聚合物（海藻酸钠/Alginate/Capsul®、羧甲基纤维素（carboxymethyl cellulose））为载体基质，制备了缓释型氮磷复合物，并将其与农用产品Osmocote®以及矿物培养基Bushnell-Haas进行对比，以评估其作为烃类降解生物刺激剂用于环境污染物生物修复的效果。本研究采用冷冻干燥法（lyophilization）与离子凝胶法（ionic gelation）实现了氮（N）、磷（P）的固定化负载。以包埋材料开展实验，分别评估其生物量生成、以葡萄糖为有机碳源时的底物消耗效率以及氮磷缓释性能。相较于游离营养盐体系（糖苷降解率11.3%、微生物生物刺激效果为150 mg·L⁻¹蛋白），固定化羧甲基纤维素复合物的糖苷降解率可达66.7%，微生物生物刺激效果可达350 mg·L⁻¹蛋白，表现最优。综上，该复合物具备作为生物修复工艺用缓释制剂的应用潜力。