Department of Biology (Biotechnology), Faculty of Science, Hacettepe University, 06800, Beytepe, Ankara, Turkey.
Arch Microbiol. 2021 Dec;203(10):5937-5950. doi: 10.1007/s00203-021-02490-5. Epub 2021 Oct 1.
Mycoremediation is an important process that targets the removal of petroleum hydrocarbons by fungi. Fungi have advantages with their extensive enzymatic systems, rapid adaptation to toxic organic pollutants, and to adverse environmental conditions. In this study, the colorimetric method was used for the preliminary investigation of petroleum degradation with ten fungal strains. Petroleum degradation ability of spore suspension, live biomass (fungal pellet and disc) and cell-free culture supernatant of the potent A. ochraceus strain were investigated by gravimetric analysis. It was found that the fungal disc (94%) was more successful than the spore suspension (87%) in petroleum degradation under physiological conditions determined as pH:5.0, 1% of petroleum concentration, 5% (v/v) of inoculum concentration (with spore suspension) and 1 g/100 mL of inoculum amount (with fungal disc) and 7 days of the incubation period. The degradation rate constant and half-life period of spore suspension were calculated as 0.291 day and t = 0.340 and of the fungal disc were 0.401 day and t = 0.247. Although, 7.5% and 10% (v/v) concentration of cell-free culture supernatant achieved more than 80% petroleum removal, it was not as effective as a fungal disc. According to gas chromatography/mass spectrometry analysis, the fungal disc of A. ochraceus strain degraded long-chain n-alkanes such as C and C more effectively than n-alkanes in the range of C-C. The fact that the A. ochraceus NRRL 3174 strain has a high petroleum degradation capacity as well as being a potent biosurfactant producer will provide a different perspective to advanced mycoremediation studies.
真菌的生物修复是一种重要的过程，旨在去除石油烃。真菌具有广泛的酶系统、对有毒有机污染物的快速适应能力以及对不利环境条件的适应能力等优势。在这项研究中，使用比色法对十种真菌菌株的石油降解进行了初步研究。通过重量分析研究了孢子悬浮液、活生物量（真菌球和圆盘）和产色曲霉（A. ochraceus）强菌株的无细胞培养上清液对石油的降解能力。结果发现，在生理条件下，真菌圆盘（94%）比孢子悬浮液（87%）更成功地降解石油，生理条件为 pH：5.0、石油浓度为 1%、接种浓度为 5%（v/v）（孢子悬浮液）和 1 g/100 mL 接种量（真菌圆盘）和 7 天的培养期。孢子悬浮液的降解速率常数和半衰期分别计算为 0.291 天和 t=0.340，真菌圆盘的降解速率常数和半衰期分别为 0.401 天和 t=0.247。尽管 7.5%和 10%（v/v）浓度的无细胞培养上清液达到了 80%以上的石油去除率，但效果不如真菌圆盘。根据气相色谱/质谱分析，产色曲霉（A. ochraceus）NRRL 3174 菌株的真菌圆盘比 C-C 范围内的 n-烷烃更有效地降解长链 n-烷烃，如 C 和 C。产色曲霉（A. ochraceus）NRRL 3174 菌株具有较高的石油降解能力，同时也是一种有效的生物表面活性剂产生菌，这将为先进的生物修复研究提供一个不同的视角。
