餐厨垃圾高温好氧生物减量菌种的筛选及特性

Screening of bacteria for thermophilic aerobic biodegradation of food waste and the degradation characteristics

摘要:

【背景】随着餐厨垃圾产生量的逐步提高，如何实现其快速降解，成为餐厨垃圾处理亟待解决的问题。餐厨垃圾的高温好氧生物减量技术是一种可以快速降解餐厨垃圾的有效方法。【目的】筛选能够适应餐厨垃圾环境且具有高效降解餐厨垃圾中有机物能力的菌株，以提高餐厨垃圾的降解效率和减量效果。【方法】采用温度梯度耐受性实验和餐厨垃圾浸出液高油高盐耐受性实验进行菌种初筛，并利用产酶培养基复筛及餐厨垃圾生物减量实验验证。【结果】通过初筛、复筛和功能验证，最终获得4株生物减量效果优良的菌株N3-1、C7、N3-3和G6-1，其对餐厨垃圾挥发性固体(volatile solid，VS)的降解率分别为36.95%、33.23%、32.83%和31.91%，是对照组的3.02、2.71、2.68和2.61倍。经鉴定，这4株菌分别属于热嗜油地芽孢杆菌(Geobacillus thermoleovorans)、史氏芽孢杆菌(Bacillus smithii)、热解木糖地芽孢杆菌(Geobacillus caldoxylosilyticus)和立陶宛地芽孢杆菌(Geobacillus lituanicus)。【结论】筛选出的4株菌均具有较强的餐厨垃圾原料适应性和高效的生物降解能力，为开发餐厨垃圾高温好氧复合菌剂奠定了基础，并为实现餐厨垃圾减量化、无害化处理和资源化利用提供了技术支持。

Abstract:

[Background] Food waste tends to increase and thus it is an urgent task to rapidly digest it. The thermophilic aerobic biodegradation technology turns to be an effective solution. [Objective] To screen the thermophilic aerobic bacteria which can adapt to food waste and decompose the organic matter in the waste and thereby to improve the degradation efficiency and reduce the waste. [Methods] Experiments on the temperature tolerance in casamino acids, yeast extract, salts (CYS) medium and high-oil and high-salt tolerance in food waste leachate medium were conducted for the primary screening of strains. The enzyme production test was used for re-screening of strains, and food waste biodegradation test for functional verification. [Results] Strains N3-1, C7, N3-3 and G6-1 were finally screened out. The degradation rate of volatile solid (VS) was 36.95%, 33.23%, 32.83% and 31.91%, respectively, 3.02, 2.71, 2.68 and 2.61 times that of the control group. They were identified as Geobacillus thermoleovorans, Bacillus smithii, G. caldoxylosilyticus and G. lituanicus, separately. [Conclusion] The 4 strains have strong adaptability to food waste and high efficiency of degrading the waste. This study lays a foundation for the development of thermophilic aerobic microbial agent and provides technical support for the reduction, harmlessness treatment and resource utilization of food waste.