绿萝根际微生物中甲醛降解菌的筛选及回用

Screening and Reuse of Formaldehyde-Degrading Bacteria in Rhizosphere Microorganisms of Epipremnum Aureum

利用植物和微生物联合处理空气中甲醛被认为是一种高效、经济且环保的方法。从盆栽绿萝的根际微生物群落中,成功分离了一株甲醛高效降解菌LL3-1(革兰氏阳性,兼性好氧菌),SEM观测为,杆状,不透明,直径在712.8 nm^1.146μm之间,宽度在199.4~495.5 nm之间。经16S rDNA鉴定为植物内生赖氨酸芽孢杆菌(GenBank编号MN784374)。通过液态甲醛降解实验,LL3-1菌株在最优的降解条件下(温度35℃,转速150 r/min,pH值7.0),6 h内可完全降解浓度为500 mg/L的甲醛溶液。在菌株回用实验中,将100 mL菌液均匀喷洒在绿萝的叶面,采用动态熏蒸系统探究LL3-1菌株日间和夜间净化气态甲醛的潜力。结果表明:在日间(7:00)和夜间(19:00)各进行一次喷洒后,绿萝平均甲醛净化效率日间提高了33.1%±1.28%,夜间提高了12.17%±2.25%。这表明,菌株LL3-1不仅能降解高浓度甲醛溶液,而且在与植物联用处理空气污染物方面具有较大潜力。

Combinationusing plants with microorganisms to gaseoustreat formaldehyde was considered to be an efficient,economical and environmentally friendly method.In this paper,a formaldehyde-degrading bacterium LL3-1(gram-positive and facultative aerobic)was successfully isolated from the rhizosphere microbial community of Epipremnum Aureum.From the Scanning electron microscope(SEM)photos,the bacterium LL3-1 were rod-shaped,opaque,with diameter ranging from 712.8 nm to 1.146μm,and width ranging from 199.4 nm to 495.5 nm.Byusing 16S rDNA technology,the bacterium LL3-1was identifiedas a Lysinibacillus endophyticus strain(with a unique GenBank accession number of MN784374).From results of the liquid formaldehyde degradation experiment,LL3-1 strain can completely degrade formaldehyde solution up to 500 mg/L in 6 hours under the environment of 35℃,a rotational speed of 150 r/minand a pH7.0.Finally,the 100 mL bacterial liquidwithin culture mediumwas sprayed on the leaves of Epipremnum Aureum,and the dynamic fumigation system was used to explore the potential of LL3-1 strain combined with Epipremnum Aureum in purifying gaseous formaldehyde both in daytime and at night.The results showed that after two time of spraying both in the daytime(7:00)and at night(19:00),the average formaldehyde purification efficiency of Epipremnum Aureum increased by 33.1%±1.28%in daytime and 12.17%±2.25%at night.This indicates that strain LL3-1 can not only degrade high concentration formaldehyde in solution,but also has great potential in treating air pollutants in combination with plants.