Читать книгу Biomolecules from Natural Sources - Группа авторов - Страница 15

Oil spills during the transport, exploration or refining of petroleum products cause huge environmental hazards. The primary transportation method of oil products is via ship, which increases marine oil contamination due to the routine operations of ship washing, and accidents during exploration and transportation (Souza et al. 2014). Conventionally the spilled oil is removed via physicochemical methods, which doesn’t solve the problem in the long term, since the contaminants are simply removed from one environment to another, which often results in the development of even more toxic byproducts. For this reason, the search for biological alternatives, such as biosurfactants, is important to contribute to environmental health (Silva et al. 2014).

Generally, bioremediation is a process where toxic compounds are fully or partially degraded through living organisms such as bacteria or plants.

The production of biosurfactants generally requires a hydrophobic and hydrophilic carbon source in the culture medium. This process is economically and environmentally friendly when using waste products as substrates (Silva et al. 2014). The biodegradation of the oil-derived compounds is based on different mechanisms. Through the production of biosurfactants the bioavailability of the hydrophobic substrate for the producing bacterium increases, whereby the surface tension of the medium around the bacteria reduces, which results in a lower interfacial tension. Another mechanism is a membrane modification through an interaction of the cell surface and the biosurfactant, which increases the hydrophobicity of the cell wall by reducing the lipopolysaccharide index through an adhesion of the hydrocarbons, without damaging the membrane. Through these mechanisms the formation of hydrogen bonds is blocked and the surface/interfacial tension is reduced, enhancing the dispersion of the hydrocarbon into micelles (which breaks down the biomass into drops) and amplifies the bioavailability and biodegradability (Aparna et al. 2011; Santos et al. 2016).

Regarding the environmental industry trehalose lipids are used as microbial-enhanced oil recovery, biodegradation of polycyclic aromatic hydrocarbons or oil-spill treatments, in the cosmetics industry and most importantly in the biomedical field with biologic properties, like anti-microbial, anti-viral (Azuma et al. 1987) and anti-tumor activities (Franzetti et al. 2010; Gudiña et al. 2013; Kadinov et al. 2020). Moreover, they can act as therapeutic agents due to their functions in cell membrane interactions (Franzetti et al. 2010).