Pseudomonas putida ATCC 17514 was used as a model strain to investigate the characteristics of bacterial growth in the presence of solid fluorene and phenanthrene. Despite the lower water‐solubility of phenanthrene, P. putida degraded this polycyclic aromatic hydrocarbon (PAH) at a maximum observed rate of 1.4 ± 0.1 mg L⁻¹ h⁻¹, higher than the apparent degradation rate of fluorene, 0.8 ± 0.07 mg L⁻¹ h⁻¹. The role of physiological processes on the biodegradation of these PAHs was analyzed and two different uptake strategies were identified. Zeta potential measurements revealed that phenanthrene‐grown cells were slightly more negatively charged (–57.5 ± 4.7 mV) than fluorene‐grown cells (–51.6 ± 4.9 mV), but much more negatively charged than glucose‐grown cells (–26.8 ± 3.3 mV), suggesting that the PAH substrate induced modifications on the physical properties of bacterial surfaces. Furthermore, protein‐to‐exopolysaccharide ratios detected during bacterial growth on phenanthrene were typical of biofilms developed under physicochemical stress conditions, caused by the presence of sparingly water‐soluble chemicals as the sole carbon and energy source for growth, the maximum value for TP/EPS during growth on phenanthrene (1.9) being lower than the one obtained with fluorene (5.5). Finally, confocal laser microscopy observations using a gfp‐labeled derivative strain revealed that, in the presence of phenanthrene, P. putida::gfp cells formed a biofilm on accessible crystal surfaces, whereas in the presence of fluorene the strain grew randomly between the crystal clusters. The results showed that P. putida was able to overcome the lower aqueous solubility of phenanthrene by adhering to the solid PAH throughout the production of extracellular polymeric substances, thus promoting the availability and uptake of such a hydrophobic compound.

Gasification of lignocellulosic biomass has been widely highlighted as one of the most robust and promising low-carb approaches toward sustainable energy production. The gasification syngas obtained from agro-industrial residues can produce heat, power, biohydrogen, and other drop-in biofuels via F-T (Fischer-Tropsch) synthesis. However, the tar formation during the thermochemical process imposes severe limitations on the commercial scale of this technology. Tar elimination is a critical step for avoiding damage to equipment and not restricting the further application of syngas. In this context, this work sheds light on the biomass gasification field and reviews some aspects of tar formation and technologies for its reduction and removal. The approaches for dealing with tar are primary methods, which suppress or remove tar within the gasifier, and secondary methods, which remove tar in post-operation treatment. Catalytic reforming offers the most cost-effective pathway to removing tar. The bimetallic combination of nickel with other metals and using biochar as support have been intensely investigated, showing excellent tar conversion capacity. Recent research has provided new trends in non-thermal plasma-catalyzed biomass tar reforming. Future studies should focus on the integration of catalysts with multiple techniques to improve efficiency and reduce energy consumption.

The production of residual biomass, such as vine pruning, presents environmental problems since its elimination is usually carried out through the uncontrolled burning of the remaining materials and with the emission of greenhouse gases without any counterpart. The use of these residues to produce biochar presents several advantages. In addition to the more common energy recovery, other conversion ways allowing new uses, such as soil amendment and carbon sequestration, can be analyzed as options as well. In the present study, vine pruning biomasses are characterized to evaluate the behavior of the different constituents. Then, the different possible applications are discussed. It is concluded that materials resulting from the pruning of vineyards have excellent characteristics for energy recovery, with an increment of more than 50% in the heating value and almost 60% in the carbon content when carbonized. This recovery procedure contributes to creating new value chains for residual materials to promote sustainable practices in the wine sector.

Waste management is a current and transversal problem in all production areas, including agriculture. Within this economic activity, wine production generates a large amount of waste, namely, that resulting from the winemaking activity itself, such as pomace and grape stalks, and waste resulting from the management of the vineyards, with operations such as vine pruning. The management of vine pruning residuals has traditionally been conducted by burning leftovers on-site, without any use for the energy produced. This research analyzed the potential for the valorization of residual biomass resulting from vine pruning by creating a business model based on value chains of local scale. For this analysis, several samples of residues resulting from the “Loureiro” vine variety planted in Ponte de Lima (northern Portugal) were collected and characterized. The objective of the small-scale business model created, in addition, to solving the environmental problems related to the disposal of waste from agricultural activities, a value chain can be established, contributing to increasing the income of the farmers while introducing a circular bioeconomy and sustainable rural development practices.