Stable carbon isotope evidence for the microbial origin of C-14-C-18 n-alkanoic acids in soils
Stable carbon isotope evidence for the microbial origin of C-14-C-18 n-alkanoic acids in soils
复制标题
DOI：
10.1016/0146-6380(95)80006-d
复制
发表时间：
1995-09-01
影响因子：
3
通讯作者：
Vallaeys, T
中科院分区：
文献类型：
--
作者：
Lichtfouse, E;Berthier, G;Vallaeys, T
为了描述土壤脂肪酸的来源，作物土壤样品在体外与未标记或C-13标记的葡萄糖孵育21天。通过气相色谱-燃烧-同位素比监测质谱法（GC-C-IRMS）对来自一元羧酸级分的C-14-C-32正链烷酸（作为甲酯）的分析表明，C-14、C-16和C-18正链烷酸是C-13标记的，从而证明它们源自实验期间生长的土壤微生物，例如真菌或细菌。高级正链烷酸、C-16-C-33正链烷和C-22-C-30正链烷醇未被显著标记，因此表明它们源自其他来源，例如高等植物。这种利用稳定碳同位素的短期示踪实验是研究土壤和沉积物等其他系统中有机质转化的一种新颖而富有成效的方法。
In order to delineate the origin of soil fatty acids, crop soil samples have been incubated for 21 days in vitro either with unlabelled or C-13-labelled glucose. Analyses of C-14-C-32 n-alkanoic acids from monocarboxylic acid fractions, as methyl esters, by gas chromatography-combustion-isotope ratio monitoring mass spectrometry (GC-C-IRMS) show that C-14, C-16 and C-18 n-alkanoic acids are C-13-labelled, thus demonstrating their derivation from soil microorganisms, e.g. fungi or bacteria, growing during the experiment. Higher n-alkanoic acids, C-16-C-33 n-alkanes, and C-22-C-30 n-alkanols have not been significantly labelled, thus suggesting their derivation from other sources, e.g. higher plants. This short-term tracer experiment using stable carbon isotopes represents a novel and fruitful approach to study organic matter transformations in soils and other systems such as sediments.