Degradation of Extra-Heavy Crude Oil by Fungi Isolated from Hydrothermal Vents Fields in the Gulf of California
Lucia Romero-Hernández, Itandehui Betanzo-Gutiérrez, Rafael Vázquez-Duhalt, Mario Figueroa, Meritxell Riquelme, Patricia Vélez
Abstract
Microorganisms from hydrothermal vents fields in the Pescadero Basin represent a promising source for biotechnological applications due to their adaptation to extreme environments. The hydrocarbon seeps in the Pescadero Basin provide a natural precedent for native fungi capable of biodegrading crude oil. In this study, the ability of eight fungal isolates from hydrothermal vent sediments in the Pescadero Basin to bioconvert extra-heavy crude oil (EHCO) was evaluated. Among the isolates, Penicillium sp. 1, Penicillium miczynskii, and Aspergillus terreus degraded different percentages of EHCO, as assessed by gravimetry. Aspergillus sydowii showed the best performance, degrading 40% of EHCO, while Aspergillus sp. 4 showed no significant EHCO degradation. Fungal interaction with EHCO was further explored using scanning electron microscope (SEM). The mycelial growth on EHCO as the sole carbon source was confirmed through the determination of intracellular protein, which was compared to controls lacking a carbon source. Additionally, GC analysis of the saturate fraction of EHCO revealed that A. sydowii degraded 38.26% of it, highlighting its potential as a promising bioremediation agent.