## 1 Introduction  
The presence of hydrocarbons in waters is extremely common. On some occasions, this is due to accidental spills of a greater or lesser extent and on other occasions, this is due to constant leaks from the production, storage or transport areas. As a result, hydrocarbon contamination can be often detected in water. Hydrocarbons are compounds produced by a combination of hydrogen and carbon; many of them, such as the polycyclic aromatic hydrocarbons (PAH) or benzene, toluene, ethyl benzene and the three xylenes compounds BTEX, have toxic, mutagenic and carcinogenic properties [1; 2; 3]. Hydrocarbon water pollution is an environmental problem that affects aquatic ecosystems and species, as well as their by-products. Therefore, this type of pollution, which has a significant impact on human health and the environment, attracts considerable interest and is a cause for concern not only among the scientific community but also at the social and political level [4]. Thus, in order to maintain water quality, the search for cost-effective decontamination and cleaning techniques is needed. Some physical remediation strategies involve the use of pollutant-absorbing sorbents. Various absorbent materials have been used for the removal of oils and grease from both wastewater and the surface of seawater. In general, they are hydrophobic materials and among those available on the market, polypropylene and polyethylene compounds stand out [5]. In this sense, [PERSON] et al. highlight the great interest in these sorbents for the removal of oils and greases basically due to the affinity for oil, hydrophobicity and durability and because they are generally cheap and do not cause toxic by-products [6]. However, because these systems create a subsequent waste management problem technically burdensome and economically costly, different authors have proposed the use of physical-bioremediation strategies in order to reduce economic cost and environmental risks [7; 8]. There are different types of sorbent materials, with granular cork and meltblown polypropylene being the most important. Granular cork is a natural carrier that has demonstrated a noticeable biosorption property and is highly efficient in the removal of heavy metals and other organic pollutants such as polycyclic aromatic hydrocarbons (PAH). Granular cork is widely used as a hydrocarbon sorbent due to their high oil sorption capacity, low water retention and the possibility of reuse [9; 10], while meltblown polypropylene is a synthetic carrier which has a high sorption capacity and is available in several physical and chemical resistant configurations; its low density, low water uptake and its excellent physical and chemical resistance are highlighted as the main properties to choose this sorbent for water oil recovery [11]. The biological process of bioremediation removes the majority of environmental hydrocarbons through the action of microorganisms, which mineralize or convert organic compounds into less noxious and dangerous substances [12; 13]. The effectiveness of bioremediation is basically due to the fact that most hydrocarbons can be degraded by microorganisms and because the degrading native microbiota is rapidly and effectively enriched in any ecosystem after the arrival of the contaminant [14; 15]. The biodegradation potential of microorganisms isolated from oil-polluted sites is a consequence of a dynamic enrichment of degrader taxa together with a decrease in biodiversity [2; 14; 15]. Several authors have studied the use of microorganisms to break down petroleum products and have reported a wide range of degraders and how environmental factors such as available nutrients, the concentration of the contaminant, temperature, pH or salinity will influence the microbial activity and the diversity of the predominant microbial groups. In this sense, [PERSON] et al. [7] reported the strong selection of bacteria from the Alcanivorax/Fundibacter groups (alkane degraders) observed during the bioremediation process in diesel-contaminated microcosms.