南美天胡荽及其根际土壤水浸提液化感成分分析

Analysis of allelochemicals in water extracts of plant and rhizospheric soil of Hydrocotyle vulgaris

为探讨南美天胡荽对其他植物种子萌发的影响以及筛选影响其他植物的主要化合物,该文采用种子萌发试验、气相色谱-质谱联用以及液相色谱-质谱联用的方法,分析了南美天胡荽不同溶剂浸提液对种子萌发的影响、南美天胡荽植株及其根际土壤浸提液成分。结果表明:(1)南美天胡荽不同溶剂浸提物均具有一定程度的抑制种子萌发作用。(2)气相色谱-质谱分析下,南美天胡荽植株水浸提液中共分离鉴定了35种化合物,其中,邻苯二甲酸二丁酯(15.2%)、10,15-十八烷二元酸(8.58%)、2,4-二叔丁基苯酚(6.81%)相对含量最高;根际土壤水浸提液中共分离鉴定了17种化合物,其中,油酸酰胺(26.47%)、正二十七烷(9.63%)、十六酸乙酯(4.83%)相对含量最高。(3)液相色谱-质谱分析下,南美天胡荽植株水浸提液共分离鉴定了109种化合物,ESI+模式下,L-苯丙氨酸(3483.99 ng·mg^-1)、木犀草素(2306.64 ng·mg^-1)含量最多,ESI-模式下,右旋奎宁酸(21827.71 ng·mg^-1)、绿原酸(12589.25 ng·mg^-1)含量最多;根际土壤水浸提液中共分离鉴定了93种化合物,ESI^+模式下,丁酸(7660.53 ng·mg^-1)、棕榈酰胺(3200.36 ng·mg^-1)含量最多,ESI^-模式下,正二十八酸(18605.35 ng·mg^-1)、蔗糖(12183.23 ng·mg^-1)含量最多。(4)南美天胡荽的潜在化感物质主要为脂肪酸类、酰胺类、酯类、芳香酸类化合物,而土壤中直接起化感作用的物质可能为丁酸、正二十八酸、羟基乙酸、油酸酰胺、棕榈酰胺、十六酸乙酯、苯甲酸,其中脂肪酸类化合物输入可能来源于南美天胡荽、土壤微生物和土壤动物,酰胺类、酯类、芳香类化合物则更可能来源于南美天胡荽植株。

In order to explore the effects of Hydrocotyle vulgaris on seed germination of other plants and to screen the main allelochemicals,the seed germination test was used to investigate the effects of leach liquors by different chemical solvents on seed germination,and the methods of gas chromatography mass spectrometry(GC-MS)and liquid chromatography mass spectrometry(LC-MS)were selected to analyse the compounds of water extracts of H.vulgaris and its rhizosphere soil which could affect other species.The results were as follows:(1)The different extracts of H.vulgaris inhibited the seed germinating of Raphanus sativus,Brassica chinensis,Cucumis sativus,and the inhibition effects were significant for Raphanus sativus.(2)By GC-MS,35 and 17 compounds were identified from water extracts of plants and rhizospheric soils.The main compounds included dibutyl phthalate,10,15-Octadecane diacid and 2,4-Di-tertbutylphenol in water extract of plants and oleic acid amide,N-hexadecane and ethyl palmitate in the water extract of rhizospheric soil.(3)By LC-MS,109 and 93 compounds were identified from water extracts of plants and rhizospheric soils.By ESI^+,L-phenylalanine and luteolin were the main compounds in water extract of plants and L-phenylbutyric acid and palmitamide were the main compounds in rhizospheric soil.By ESI^-,L-phenylpropyl dextro-quinic acid and chlorogenic acid were the main compounds in water extract of plants,and L-phenylpropanoid octadecanoic acid and sucrose were the main compounds in rhizospheric soils.(4)These compounds included butyric acid,octadecanoic acid,glycolic acid,oleic amide,palmitamide,ethyl hexadecanoate,benzoic acid could affect the growing and surving of companion organism directly,which belonged to fatty acids,amides,esters and aromatic acids.These compounds included oleic amide,palmitamide,ethy hexadecanoate,benzoic acid may originate in plants or transformed from secretion of plants by soil organisms.The input pathways of butyric acid,octadecanoic acid,glycolic acid include seereting of plants transforming of micro organisms and soil animals.