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Background: The valorization of byproducts to obtain high nutritional value foods is of utmost importance for our planet where the population is booming. Among these products are oils rich in ω-3 fatty acids produced from fishery byproducts. Recently, mullet roe oil from roe byproducts was produced that was rich in the ω-3 fatty acids eicosatetraenoic acid (EPA) and docosahexaenoic acid (DHA). Oils are customarily characterized for their composition and degree of oxidation but little is known of their biological effects, especially the effect of the extraction method. Methods: The purpose of this study was to evaluate the effects of freshly extracted mullet roe oil from mullet roe byproducts and the effect of the extraction method on human red blood cells (hRBCs) and platelets. To this end, the hemocompatibility (cytotoxicity), oxidative effects, and erythrocyte membrane changes were examined after 1 and 24 h of incubation. Antiplatelet effects were also assessed in vitro. Results: The expeller press oil extraction method and alcalase-assisted extraction produced the most biocompatible oils, as shown by hemocompatibility measurements and the absence of erythrocyte membrane alterations. Solvent extracts and protease-assisted extraction oils resulted in the rupture of red blood cells at different examined dilutions, creating hemolysis. Conclusions: It seems that the proper functioning of oil–erythrocyte interactions cannot be explained solely by ROS. Further investigations combining chemical analysis with oil–cell interactions could be used as an input to design high nutritional value oils using green extraction technologies. All samples exhibited promising antiplatelet and antiblood clotting effects in vitro.

The C1–C5 gas and carbon isotope ratios generated during the cracking of heavy, normal and high-waxy marine oils from Tahe Oilfield, Tarim Basin, NW China, using a closed-gold tube system under high pressure were presented. The three types of oil tested resulted in a similar gas-generation process. The C2–C5 range initially increased its yield with the application of pyrolysis temperature and thereafter decreased, while the C1 yield increased with the same application. High-waxy oil had the highest C1–C5 yield of 510 mg/goil, whereas heavy oil had the lowest C1–C5 yield of 316 mg/goil. The δ13C1 value was low at first, but gradually became higher as the pyrolysis temperature increased. However, the δ13C2 and δ13C3 values gradually became higher when the temperature was greater than 420 °C. The kinetic parameters of the C1–C5 gas generation for the different types of marine oils were then calculated using KINETIC software. This calculation resulted in a frequency factor of about 1.78 × 1014 s−1, while the distribution of the activation energy of the C1–C5 gas mass generated was relatively narrow with a range from 56 to 66 kcal/mol. Among the three types of oil tested, heavy oil had the widest activation energy distribution and the lowest major frequency of activation energy. The maximum temperature at which oil could be preserved as a separate oil phase varied from about 178 °C at a slow geological heating rate to 206 °C at a fast geological heating rate. This result is based on the kinetic parameters determined and in combination with the fractional conversion (C) of oil to gas. Testing conducted at the volatile Middle Cambrian reservoir of well Zhongshen 1 in the Tazhong Uplift strongly supported this conclusion.

During exploitation, the engine oil undergoes the irreversible aging process that is – degradation. The speed of this process is affected by many factors such as high temperature, pressure, power output, oxygen from the air, mechanical shear forces, type, structure, and technical condition of the engine, time and conditions of work and also used fuel. In the article, the author shows that also the purpose of the engine influences the degradation of the engine oil. Using the method of optical emission spectrometry in accordance with ASTM D 6595 standard, the concentration of trace elements like: Ag, Al, B, Ba, Ca, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Pb, Si, Ti, V, Zn, was determined. The samples of engine oil – Marinol RG 1240 were checked after various periods of use in three different engine types Cegielski – Sulzer.

The benefits ascribed to marine oils rich in n-3 polyunsaturated fatty acids has led to efforts to improve the chemical and organoleptic characteristics of these oils and to develop procedures for the obtention of pure or highly concentrated fractions of some n-3 fatty acids. Two n-3 fatty acids are of main interest; the eicosapentaenoic acid (C20:5, EPA) and the docosahexaenoic acid (022:6, DHA). The present review is referred to the identification of the main sources of marine n-3 polyunsaturated fatty acids, and to the stabilization of these fatty acids against oxidative rancidity. In addition the procedures for the obtention of EPA and DHA concentrates and the utilization of these fatty acids for nutritional or pharmacological purposes are also discussed.