a b s t r a c tBased on the presence of phospholipids in the extracellular fluids (EFs) of sunflower seeds, we have hypothesized on the existence of vesicles in the apoplastic compartment of plants. Ultracentrifugation of sunflower EF allowed the isolation of particles of 50-200 nm with apparent membrane organization. A small GTPase Rab was putatively identified in this vesicular fraction. Since Rab proteins are involved in vesicular traffic and their presence in exosomes from animal fluids has been demonstrated, evidence presented here supports the existence of exosome-like vesicles in apoplastic fluids of sunflower. Their putative contribution to intercellular communication in plants is discussed.

Oily bilge wastewater (OBW) is a hazardous hydrocarbon-waste generated by ships worldwide. In this research, we enriched, characterized and study the hydrocarbon biodegradation potential of a microbial consortium from the bilges of maritime ships. The consortium cZ presented a biodegradation efficiency of 66.65% for total petroleum hydrocarbons, 72.33% for aromatics and 97.76% removal of n-alkanes. This consortium showed the ability to grow in OBWs of diverse origin and concentration. A 67-fold increase in biomass was achieved using a Sequential Batch Reactor with OBW as the only carbon and energy source. The bacterial community composition of the enriched OBW bacterial consortium at the final stable stage was characterized by 16S amplicon Illumina sequencing showing that 25 out of 915 of the emerged predominant bacterial types detected summed up for 84% of total composition. Out of the 140 taxa detected, 13 alone accumulated 94.9% of the reads and were classified as Marinobacter, Alcanivorax, Parvibaculum, Flavobacteriaceae, Gammaproteobacteria PYR10d3, Novispirillum and Xanthomonadaceae among the most predominant,

Oily bilge wastewater is one of the main sources of hydrocarbons pollution in marine environments due to accidental or clandestine discharges. The main technical challenge for its effective treatment is the presence of stable oil-in-water (O/W) emulsions. In this work we are reporting an enriched microbial consortium from bilge wastewater with remarkable ability to demulsify oil in water emulsions. The consortium showed emulsion-breaking ratios up to 72.6% in the exponential growth phase, while the values range from 11.9 to 8.5% in stationary phase. A positive association was observed between demulsifying ability and microbial adhesion to hydrocarbons, as well as between cell concentration and demulsifying ability. Also, an interesting ability to demulsify under different temperatures, conditions of agitation, and bilge emulsions from different vessels was observed. The Bacterial and Archaeal composition was analyzed by 16S rRNA gene amplicon lllumina sequencing analyses, revealing an assemblage composed of bacterial types highly related to well characterized bacterial isolates and also to non-yet cultured bacterial types previously detected in marine and sediment samples. Hydrocarbonoclastic microbial types such as Marinobacter, Flavobacteriaceae, Alcanivorax and Gammaproteobacteria PYR10d3 were found in high relative abundance (27.0%-11.1%) and types of marine oligotrophs and surfactant degraders such as Thallasospira, Parvibaculum, Novospirillum, Shewanella algae, and Opitutae were in a group of middle predominance (1.7-3.5%). The microbial consortium reported has promising potential for the biological demulsification of bilge wastewater and other oily wastewaters.

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