## 1 Introduction  
Fuel oils are commonly used worldwide. Despite significant improvements in handling, transportation, and containment, they still enter water and soil environments. The most severe damage to natural ecosystems has been reported after accidental releases [1]. Engine oil is a complex mixture of hydrocarbons, engine additives, and metals like aluminum, chromium, copper, iron, lead, manganese, nickel, and silicon. Engine oil contains hundreds of aliphatic, linear, or branched and aromatic hydrocarbons [2], most of which are toxic to living organisms [3, 4]. Hydrocarbons can accumulate in animal organs directly or indirectly through the food chain [5]. In humans, prolonged exposure to or contact with high concentrations of hydrocarbons can cause liver or kidney disease, bone marrow damage, reproductive disorders, and increased risk of cancer [6, 7]. Oil products can also have important repercussions on the environment and plants. In fact, they can create a thick layer on plant organs, reducing their metabolic activities and physical capacities [8]. Conventional treatments to remove hydrocarbons from the environment are efficient but very expensive and often require the use of chemicals in operational steps that alter the structure and composition of soil and subsoil, as well as changing the autochthonous microbial population [9; 10]. An unconventional and environmentally friendly method of treating hydrocarbon-contaminated soils is bioremediation, which is the exploitation of natural microbial metabolism and co-metabolism to degrade toxic contaminants [4]. For these reasons, bioremediation is a \"green\" strategy, simple to design, and cost-effective. Filamentous fungi are potential agents of degradation because they possess branched hyphae with which they can reach the deepest portions of contaminated substrates, digesting it through the secretion of extracellular enzymes [11]. Most fungi produce enzymes that include manganese peroxidase (MnP), lacases (Lac), cytochrome P450 monooxygenases, and epoxide hydrolases [12]. These extracellular enzymes, usually involved in the oxidation of lignin, are not substrate-specific and can therefore oxidize a wide range of xenobiotics, including pesticides, plastics, and hydrocarbons. Moreover, fungi can grow under different and extreme environmental conditions [13; 14]. Among the different species of filamentous fungi, _Trichoderma_ represents a genus with high potential. _Trichoderma_ species belong to the Hypocreales order of the phylum Ascomycota, usually present in soils and plant roots [15]. This genus is one of the most widely distributed fungal groups in terrestrial and aquatic ecosystems [16]. It is resistant to most agrochemicals [17], heavy metals, pesticides, and polycyclic aromatic hydrocarbons (PAHs) [18]. The genus _Trichoderma_ is often used as a biocontrol agent of plant pathogens since its species are mycop parasites and antibiotic producers. They can regulate the growth and incidence of microorganisms that cause diseases in several horticultural plants [19; 20]. During the last few decades, many research teams started to focus their attention on the possibility of exploiting the properties of _Trichoderma_ in the bioremediation of petroleum hydrocarbons. [PERSON] et al. [21] showed that some _Trichoderma_ species contributed to the degradation of a saturated hydrocarbons fraction in a petroleum sample. _T. harzianum, T. pseudokoningii_, and _T. viride_ can utilize pyrene as a carbon source [22; 23]. [PERSON] and [PERSON] [24] demonstrated that the strain _Trichoderma_ S019 can degrade 73% of n-eicosane when glucose is applied as a carbon source. Other researchers reported the ability of T. _hamatum_, T. _harzianum_, T. _koningii_, T. _viride_, T. _virens_, and _T. _saperellum_ in the degradation of low-molecular-weight PAHs such as naphthalene and phenanthrene, or more complex PAHs such as anthraceenbenzo[a]anthracene, benzo[a]fluoranthene, benzo[a]pyrene, and chrysene [25; 26; 12]. [PERSON] et al.