溶藻菌R1的溶藻特性

Algicidal characteristics of algicidal bacteria R1

以铜绿微囊藻(Microcystis aeruginosa)为受试对象,考察了从太湖土著激荡鱼内脏中筛选的溶藻菌R1菌(Lysinibacillus macroides)的溶藻特性,通过chl-a测定、三维荧光技术,采用高温处置、酸碱处置、透析处置手段,HPLC分离技术,考察了溶藻效果、溶藻产物、溶藻机制及溶藻活性物质。结果表明:菌株R1具有较强的溶藻特性,10d内chl-a含量从205.11mg/L降至35.61mg/L,溶藻率达82.64%;采用荧光强度表征溶藻率,10d溶藻率达89.80%,与chl-a表征的溶藻率82.64%相近;R1溶藻活性物质是细菌分泌的胞外耐高温类物质,为小分子物质(Mr<500da),具有耐酸性碱性;荧光图谱EMMs结合平行因子PARAFAC模型谱分析显示溶藻过程中色氨酸增加,腐殖酸大量减少;主要溶藻产物为长波类类色氨酸类物质,主要为细胞的胞内物质;推测溶藻活性物质疏水性氨基酸(hydrophbic acid);通过HPLC分离技术,从R1粗提液中分离出1馏分溶藻活性物质,成分还需要进一步的鉴定。

Microcystis aeruginosawas used as the experimental subject to examine the algae-lysing characteristics of algicidal bacteria R1（Lysinibacillus macroides）,which was isolated and purified from Taihu fish innards,named Surf fish.The ability of algae-lysing,the degradation products,algae-lysing mechanism and active algicidal substances were studied with the measurement of chlorophyll a and the three dimensional fluorescence technology,the whole experimental process was carried out through high temperature treatment,acid and alkali treatment,dialysis treatment and HPLC separation technique.The results show that the strain R1 can remove Microcystis aeruginosa effectively.The contents of chl-a decrease from 205.11 mg/L to 35.61 mg/L in 10 days,with degradation rate of 82.64%.The degradationrate is 89.8% measured by 3-D flurescence technology in 10 d,which is similar to the result measured by measuring Chlorophyll-a.The fluorescence spectrometric analysis shows that the tryptophan increases and the humic acid decreases significantly.The main dissolved algal products are long-wave class tryptophan,which are mainly intracellular substances.The soluble alga may be hydrophobic acid.The active algaelysing substances produced by R1 with molecular weight less than 500 da,are identified as bacteria secretion,could resist acid and be promoted in alkaline conditions.Active substance was separated from R1 crude extract by HPLC,and a further identification was necessary to be processed.