The effects of reservoir natural enviorenments, oil biodegradation and thermal recovery process on the endogenous fungal communities in crude oils

While numerous studies have focused on environmental samples linked to crude oil, direct studies on microbial communities within crude oil are rare. This study investigates the chemical compositions and microbial communities of crude oils from Henan, Bamianhe, and Jianghan oilfields using gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS), and ITS (Internal Transcribed Spacer) gene amplicon sequencing. The fungi in the crude oils of Henan oilfield were mainly composed of Aspergillus and Sterigmatomyces. The fungi in the crude oils from Bamianhe oilfield were mainly Aspergillus, Cladosporium, and Paraphoma. The fungi in the crude oils of Jianghan were mainly Aspergillus, Meyerozyma, and Phaeophleospora.