Abstract

Context: As a toxic traditional Chinese medicine for edoema, Euphorbia kansui S.L. Liou ex S.B. Ho (Euphorbiaceae) (EK) stir-fried with vinegar for detoxification was associated with alterations of gut microbiota. However, the evidence of correlation between short-chain fatty acids (SCFAs) and toxicity of EK has not been confirmed.

Objective: In order to study the biological basis of detoxification of EK stir-fried with vinegar (VEK), a rapid, sensitive and validated GC-MS method was developed to determine SCFAs in normal rat faeces after given EK and VEK.

Materials and methods: Sprague Dawley rats were orally administered 0.5% CMC-Na (control group), EK (EK-treated group) and VEK powder (VEK-treated group) at 680 mg/kg for six consecutive days (eight rats each group). Fresh faeces samples were promptly collected, derivatized and then analyzed by GC-MS.

Results: The ranges of LOD and LOQ were within 0.13–1.79 and 0.45–5.95 μg/mL, respectively. The RSD values of intra-day and inter-day precisions were less than 15%. Four SCFAs were generally stable under four storage conditions. The extraction recoveries were ranged from 53.5% to 97.3% with RSD values lower than 15%. The concentrations of four SCFAs in EK and VEK were decreased significantly compared with those not administered (EK-treated, p < 0.01; VEK-treated, p < 0.05 and p < 0.01). After being stir-fried with vinegar, the concentrations were all increased (p < 0.05 and p < 0.01).

Discussion and conclusions: The negative correlation between SCFAs and toxicity of EK may provide evidence for biological mechanism and toxic Chinese medicine.

摘要

背景：作为一种有毒的水肿中药，甘草大戟（Euphorbiaceae）（EK）用醋炒制排毒与肠道菌群的改变有关。然而，短链脂肪酸（SCFA）与EK毒性之间没有相关的证据。

目的：为了研究用醋（VEK）翻炒EK排毒的生物学基础，建立了一种快速，灵敏且有效的GC-MS方法，用于测定给予EK和VEK后正常大鼠粪便中的SCFA。

材料和方法：连续六天口服Sprague Dawley大鼠0.5％CMC-Na（对照组），EK（EK治疗组）和VEK粉（VEK治疗组），连续六天（每组八只大鼠） ）。立即收集新鲜的粪便样品，进行衍生化，然后通过GC-MS分析。

结果： LOD和LOQ的范围分别在0.13-1.79和0.45-5.95μg/ mL之间。日内和日间精度的RSD值小于15％。四种SCFA在四种储存条件下通常是稳定的。提取回收率介于53.5％至97.3％之间，RSD值低于15％。与未给药相比，EK和VEK中四种SCFA的浓度显着降低（EK治疗，p  <0.01； VEK治疗，p  <0.05和p  <0.01）。用醋炒后，所有浓度均升高（p  <0.05和p  <0.01）。

讨论与结论： SCFAs与EK毒性之间的负相关关系可能为生物学机制和中毒提供证据。