Crude Oil Biodegradation Performance in Natural Seawater of a Trichoderma species from Decaying Mangrove Wood in East Kalimantan

Large-scale petroleum production poses environmental and human health risks, particularly due to petroleum contamination in marine environments. The aim of this study was to isolate and screen fungi inhabiting decaying mangrove wood in East Kalimantan with their ability to degrade crude oil in seawater. In the initial step, fungi were isolated using standard methods and screened for crude oil degradation and biomass production. Selected fungi were based on their significant biomass production. Subsequently, the selected fungus was cultured in three types of media based on natural seawater and crude oil at initial concentrations ranging from 1% to 5% (v/v). The biodegradation of crude oil was assessed spectrophotometrically at 420 nm. Out of the 17 decaying wood fungi, MG-07 exhibited significantly higher biomass production compared to the control medium (without crude oil). Gas chromatography-mass spectrometry analysis indicated that MG-07 degraded 20%–80% of the normal aliphatic compounds in the tested crude oils within 2 weeks. Furthermore, the growth and degradation efficiency of MG-07 was significantly enhanced when cultured in a natural seawater medium containing crude oil, supplemented with glucose (20 g/L) and Tween 80 (1% v/v). The highest observed biomass gains were 867%, with a biodegradation efficiency of 31.6% at a crude oil concentration of 1%. MG-07 was identified as Trichoderma sp. based on the internal transcribed spacer region. The results obtained from this study demonstrate that MG-07 has significant potential for degrading crude oil in saline environments. These findings provide valuable insights for the application of fungi in marine oil spill remediation.