Biosurfactants are amphipathic molecules with considerable potential for application in different industries due to their biochemical characteristics, low toxicity as well as greater biodegradability and stability compared to chemical surfactants when submitted to adverse environmental conditions. The aim of the present study was to investigate the production of a biosurfactant by Candida lipolytica UCP 0988 grown in a medium containing 4.0% molasses, 2.5% used soybean frying oil, and 2.5% corn steep liquor for 144 h at 200 rpm. The biosurfactant was characterized; its stability and toxicity were investigated, and the compound was applied in oil removal tests. In the C. lipolytica growth and biosurfactant production studies, the surface tension of the medium was reduced from 72 mN/m to 25 mN/m, the critical micellar concentration (CMC) was 0.5 g/L (w/v), and the yield was 12 g/L. Tests under extreme conditions of temperature, pH, and NaCl indicated the stability of the biosurfactant. Fourier-transform infrared and nuclear magnetic resonance spectroscopy of the chemical structure of the purified biosurfactant suggested that the biosurfactant is a glycolipid. The anionic biosurfactant exhibited no toxicity to the microcrustacean Artemia salina or vegetable seeds (Brassica oleracea). Dispersion tests in seawater demonstrated 100% efficiency of the biomolecule against motor oil. The biosurfactant was efficient at removing oil from sand in static and kinetic tests at concentrations of ½ CMC (0.25 g/L), CMC (0.5 g/L), and 2 × CMC (1.0 g/L), with removal rates of 70 to 96%, whereas the synthetic surfactants tested removed only 10 to 18% of the oil. Based on the findings, the biosurfactant analyzed has considerable potential for the remediation of contaminated coastal and marine environments due to oil spills.

Biosurfactants are a group of environmentally friendly amphiphilic molecules that are applicable in numerous industries as essential biotechnology products, such as food production, cleaning products, pharmacology, cosmetics, pesticides, textiles and oil and gas fields. In this sense, and knowing the potential of these biomolecules, the aim of this work was to produce a biosurfactant, characterize it regarding its chemical and surfactant properties and investigate its potential in the removal of contaminants and in the cleaning of cotton fabrics. The biosurfactant was initially obtained from the cultivation of the microorganism Candida glabrata UCP 1002 in medium containing distilled water with 2.5% residual frying oil, 2.5% molasses and 2.5% corn steep liquor agitated at 200 rpm for 144 h. The biosurfactant reduced the surface tension of water from 72 to 29 mN/m. The toxicity potential of the biosurfactant was evaluated using Tenebrio molitor larvae and demonstrated non-toxicity. The biosurfactant was applied as a degreaser of engine oil on cotton fabric, and showed 83% (2× CMC), 74% (1× CMC) and 78% (1/2× CMC) oil removal. Therefore, the biosurfactant produced in this work has promising surfactant and emulsifying properties with potential for application in various industrial segments.

Plastics are by-products of origin from the petroleum industry, derived from oil and from the extraction of raw materials in the process of refining crude oil. In refineries, oil is fractionated into various types of organic materials, such as naphtha, gasoline, kerosene, and lubricating oils. From the naphtha that is extracted by cracking substances that give rise to conventional plastic. The last step to carry out the production of plastics is polymerization, where polymers arise, where each one differs from the other, arising from this whole process, thermoplastics, and thermosets. Therefore, it is possible to find plastics, ethylene, and propylene, such as polyethylene, polypropylene, polyvinyl chloride, epoxy resin, polyester, phenolic, silicones, and the most diverse types of plastics. Due to the extent and structure of polymers, they can be non-rigid plastics that can have different applicability. Thermosetting plastics, which do not melt by heating, are insoluble and non-recyclable and with differentiated use in various sectors. However, the widespread disorderly disposal of plastics has come to represent one of the biggest ecological problems in the pollution of marine environments, representing 80% of the garbage found in the oceans, being composed mainly of bags and bottles, among other contaminants. The outlook until 2040 shows that the volumes of plastic flowing into the sea could be tripled, with the expectation that it can present an annual quantity calculated between 23 and 37 million tons. Given this reality, studies focused on technologies capable of minimizing the impacts caused by these pollutants on environments have grown exponentially. Thus, the search for alternative measures for the reuse of plastics, being chemical, mechanical or energy recycling one of the solutions for the transformation of plastics, from the areas of biotechnology to civil construction, with the sole objective, to reduce the presence and damage caused by plastic. The highest concentration of garbage may be found in coastal regions and on the seabed. In this context, this review presents the problems of environmental pollution in the oceans caused by rigid plastics and non-rigid plastics, as well as studies directed at the displacement of plastics in the oceans and current technologies to remedy the problem.