Department of Forensic Medicine & Toxicology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece.
Department of Microbiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece.
Forensic Sci Int. 2021 Jul;324:110809. doi: 10.1016/j.forsciint.2021.110809. Epub 2021 May 1.
In previous research, we modeled the ethanol production by certain bacteria under controlled experimental conditions in an attempt to quantify the production of microbial postmortem ethanol in cases where other alcohols were co-detected. This contribution on the modeling of postmortem ethanol production by Candida albicans is complementary to these previous studies. Τhis work aimed to study ethanol, higher alcohols (1-propanol, isobutanol, 2-methyl-1-butanol and 3-methyl-1-butanol), and 1-butanol production by Candida albicans: (i) in different culture media (Brain Heart Infusion, BHI and, Sabouraud Dextrose Broth, SDB), (ii) under mixed aerobic/anaerobic or strict anaerobic conditions, and (iii) at different temperatures (37 °C, 25 °C and, 4 °C), and develop simple mathematical models, resulted from fungal cultures at 25 °C, to predict the microbially produced ethanol in correlation with the other alcohols. The applicability of the models was tested in the C. albicans cultures in BHI and SDB media at 37 °C, in denatured human blood at 25 °C, acidic and neutral with different concentrations of additional glucose, in acidic denatured blood diluted with dextrose solution and in blood from autopsy cases. The received results indicated that the C. albicans models could apply in cases where yeasts have been activated in blood with elevated glucose levels. Overall, the in vitro ethanol production by C. albicans in blood depended on temperature, time, glucose (or carbohydrate) content, pH of the medium and endogenous changes in the medium composition through time. Our results showed that methyl-butanol is the most significant indicator of fungal ethanol production, followed by the equally important isobutanol and 1-propanol in qualitative and quantitative terms.
在之前的研究中,我们尝试通过在受控实验条件下对某些细菌的乙醇生产进行建模,以量化在其他醇类共同检测的情况下微生物死后乙醇的产生。这项关于白色念珠菌死后乙醇生产建模的研究是对这些先前研究的补充。本工作旨在研究白色念珠菌产生的乙醇、高级醇(1-丙醇、异丁醇、2-甲基-1-丁醇和 3-甲基-1-丁醇)和 1-丁醇:(i)在不同的培养基(脑心浸液,BHI 和沙氏葡萄糖琼脂,SDB)中,(ii)在混合有氧/厌氧或严格厌氧条件下,以及(iii)在不同温度(37°C、25°C 和 4°C)下,并开发简单的数学模型,该模型来自 25°C 下的真菌培养物,以预测与其他醇相关的微生物产生的乙醇。在 37°C 下的 BHI 和 SDB 培养基中的白色念珠菌培养物、25°C 下的变性人血、不同浓度外加葡萄糖的酸性和中性条件下、用葡萄糖溶液稀释的酸性变性血液以及尸检案例中的血液中测试了模型的适用性。结果表明,在酵母在富含葡萄糖的血液中被激活的情况下,白色念珠菌模型可以应用。总的来说,C. albicans 在血液中的体外乙醇生产取决于温度、时间、葡萄糖(或碳水化合物)含量、培养基的 pH 值以及培养基组成随时间的内源性变化。我们的结果表明,甲基丁醇是真菌乙醇生产的最显著指标,其次是同样重要的异丁醇和 1-丙醇,在定性和定量方面都是如此。