Biosurfactants (BSs) are “green” amphiphilic molecules produced by microorganisms during biodegradation, increasing the bioavailability of organic pollutants. In this work, the BS production yield of marine hydrocarbon degraders isolated from Elefsina bay in Eastern Mediterranean Sea has been investigated. The drop collapse test was used as a preliminary screening test to confirm BS producing strains or mixed consortia. The community structure of the best consortia based on the drop collapse test was determined by 16S-rDNA pyrotag screening. Subsequently, the effect of incubation time, temperature, substrate and supplementation with inorganic nutrients, on BS production, was examined. Two types of BS – lipid mixtures were extracted from the culture broth; the low molecular weight BS Rhamnolipids and Sophorolipids. Crude extracts were purified by silica gel column chromatography and then identified by thin layer chromatography and Fourier transform infrared spectroscopy. Results indicate that BS production yield remains constant and low while it is independent of the total culture biomass, carbon source, and temperature. A constant BS concentration in a culture broth with continuous degradation of crude oil (CO) implies that the BS producing microbes generate no more than the required amount of BSs that enables biodegradation of the CO. Isolated pure strains were found to have higher specific production yields than the complex microbial marine community-consortia. The heavy oil fraction of CO has emerged as a promising substrate for BS production (by marine BS producers) with fewer impurities in the final product. Furthermore, a particular strain isolated from sediments, Paracoccus marcusii, may be an optimal choice for bioremediation purposes as its biomass remains trapped in the hydrocarbon phase, not suffering from potential dilution effects by sea currents.

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Following the global trend towards increased energy demand together with requirements for low greenhouse gas emissions, Adaptable Reactors for Resource- and Energy-Efficient Methane Valorisation (ADREM) focused on the development of modular reactors that can upgrade methane‐rich sources to chemicals. Herein we summarise the main findings of the project, excluding in‐depth technical analysis. The ADREM reactors include microwave technology for conversion of methane to benzene, toluene and xylenes (BTX) and ethylene; plasma for methane to ethylene; plasma dry methane reforming to syngas; and the gas solid vortex reactor (GSVR) for methane to ethylene. Two of the reactors (microwave to BTX and plasma to ethylene) have been tested at technology readiness level 5 (TRL 5). Compared to flaring, all the concepts have a clear environmental benefit, reducing significantly the direct carbon dioxide emissions. Their energy efficiency is still relatively low compared to conventional processes, and the costly and energy-demanding downstream processing should be replaced by scalable energy efficient alternatives. However, considering the changing market conditions with electrification becoming more relevant and the growing need to decrease greenhouse gas emissions, the ADREM technologies, utilising mostly electricity to achieve methane conversion, are promising candidates in the field of gas monetisation.