Franke Laura, Ihle Hannah, Rieger Kristina, Stammer Viviane, Niederegger Senta, Wissenbach Dirk K, Peters Frank T, Mall Gita
Jena University Hospital, Institute for Forensic Medicine, Friedrich Schiller University, Jena, Germany.
Perioperative Medizin und Notfallmedizin Helios Klinikum Erfurt, Klinik für Anästhesiologie, Erfurt, Germany.
Int J Legal Med. 2025 Jul 2. doi: 10.1007/s00414-025-03552-9.
Putrefaction is the microbial metabolism/degradation of autolysis end products like amino acids. The aim of this study was to identify and investigate amino acids and their bacterial degradation products/metabolites by LC-HRMS as possible markers of putrefaction.
Pig eyes (n = 60) were stored in conical centrifuge tubes and petri dishes within a climate chamber at 25°C, 65% humidity over four days. Each day, eyes were macroscopically examined and vitreous humour was drawn from up to six eyes. Twenty-one amino acids/metabolites (lysine, histidine, arginine, N-acetyllysine, N-acetylarginine, N-acetyllysine, N-acetylcadaverine, tyrosine, N-acetylagmatine, tyramine, phenylalanine, N-diacetyllysine, 2-phenylethylamine, tryptophan, kynurenic acid, N-acetyltyrosine, N-acetyltyramine, N-acetylphenylalanine, N-acetyltryptophan, N-acetyl-2-phenylethylamine, N-acetyltryptamine) were monitored by LC-HRMS.
Opacification was observed and eyes stored on petri dishes dried out faster and turned dark compared to eyes stored in centrifuge tubes. Amino acids were universally present and showed a significant increase by up to 46-fold from day 0 to 4, except for arginine (no trend observed). Amino acid metabolites were first detected on day 2 with exception of N-acetyllysine, N-acetylarginine, and N-acetyllysine (detected on day 0). All analytes showed a marked increase by days 3 and 4, especially kynurenic acid and N-acetylated compounds. Among the six eyes of each storage condition/day high variability was observed, between centrifuge tube and petri dish storage few variability was found.
LC-HRMS analysis of amino acids and their metabolites in vitreous humour could be a promising tool to evaluate the putrefaction status. However, further studies are required to better understand inter-individual metabolic differences and influencing environmental factors.
腐败是微生物对自溶终产物（如氨基酸）的代谢/降解过程。本研究的目的是通过液相色谱-高分辨率质谱法（LC-HRMS）鉴定和研究氨基酸及其细菌降解产物/代谢物，将其作为腐败的可能标志物。
将60只猪眼储存在锥形离心管和培养皿中，置于气候箱内，温度25°C，湿度65%，持续4天。每天对猪眼进行宏观检查，并从多达6只猪眼中抽取玻璃体液。通过LC-HRMS监测21种氨基酸/代谢物（赖氨酸、组氨酸、精氨酸、N-乙酰赖氨酸、N-乙酰精氨酸、N-乙酰尸胺、酪氨酸、N-乙酰胍丁胺、酪胺、苯丙氨酸、N-二乙酰赖氨酸、2-苯乙胺、色氨酸、犬尿氨酸、N-乙酰酪氨酸、N-乙酰酪胺、N-乙酰苯丙氨酸、N-乙酰色氨酸、N-乙酰-2-苯乙胺、N-乙酰色胺）。
观察到浑浊现象，与储存在离心管中的猪眼相比，储存在培养皿中的猪眼干燥更快且颜色变深。氨基酸普遍存在，从第0天到第4天显著增加，增幅高达46倍，但精氨酸除外（未观察到趋势）。除N-乙酰赖氨酸、N-乙酰精氨酸和N-乙酰尸胺（在第0天检测到）外，氨基酸代谢物在第2天首次检测到。所有分析物在第3天和第4天均显著增加，尤其是犬尿氨酸和N-乙酰化化合物。在每种储存条件/每天的6只猪眼中观察到高度变异性，在离心管和培养皿储存之间发现的变异性较小。
对玻璃体液中氨基酸及其代谢物进行LC-HRMS分析可能是评估腐败状态的一种有前景的工具。然而，需要进一步研究以更好地理解个体间的代谢差异和影响环境因素。
