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Graphical abstract Highlights • Halophylic fungi cell disruption with SC CO 2 or homogenization method. • Extremozymes with high catalytic activities after exposure of fungi cell suspension to SC CO 2. • High protein concentration in fungi cell suspension after the treatment with SC CO 2. Abstract Trimatostroma salinum, Wallemia ichthyophaga, Hortaea werneckii and Phaeotheca triangularis are halophilic fungi, which can thrive in a wide range of salinity (0%–32% NaCl). They present a source of valuable bio-active compounds, enzymes and proteins interesting for environmental management, food, textile and pharmaceutical industry. Enzymes from these fungi, e.g. amylases, cellulases, lipases, and proteases, which possess so called polyextremophilicity (they are thermostable, tolerant to a wide range of pH, less susceptible to denaturation and tolerant to high salt concentrations) present a novel catalytic alternative for biotechnological applications. To release enzymes from halophilic fungi cells, a conventional method using mechanical homogenizer (rotor-stator homogenizer) and a novel method using supercritical technology were applied. Very high protein concentration in all halophilic fungi cell suspensions after the treatment with SC CO 2 were detected. Obtained results also show very high activities of protease, α-amylase, β -glucosidase and cellulase after the treatment of each halophilic fungi cell suspension by SC CO 2. Using SC CO 2 as a medium for cell disruption offers additional benefits regarding performance of a biochemical reaction and bioseparation in the same medium leading in integration of all three processes into a single step. Besides, integration of processes presents important advantage in industrial processes from an economic point of view. Enzymes from extremophiles namely possess improved properties and can be used at harsh conditions where non-extremophilic enzymes may deactivate. Therefore, extremozymes from T. salinum , W. ichthyophaga, H. werneckii and P. triangularis are as high-pressure tolerant enzymes suitable for many industrial applications, which could be performed also in non-aqueous media like SC CO 2. [ABSTRACT FROM AUTHOR]

Highlights: [•] Hortaea werneckii cell suspension, cellulase from Trichoderma reesei and α-amylase from Aspergillus oryzae were treated in SC CO2. [•] Viability of H. werneckii decreased as the treatment time and pressure increased. [•] Residual activity of cellulase from H. werneckii and that of α-amylase from H. werneckii after the treatment with SC CO2 increased. [Copyright &y& Elsevier]

• Chemical recycling of PE (virgin LDPE, colored PE waste) in SCW at 425 °C and 450 °C. • High yields of wax/oil phase (up to 98%) were obtained. • Wax/oil phases were rich with aliphatic, alicyclic and aromatic hydrocarbons. • Main light hydrocarbons in gas phases were C 2 –C 4. • Potential mechanism of hydrothermal degradation of PE has been proposed. ga1 In the present study the supercritical water (SCW) degradation of polyethylene (PE) plastics (virgin LDPE, PE waste) has been investigated in a batch reactor at 380–450 °C and reaction time of 15–240 min. The experiments (virgin LDPE) were also performed with the addition of acetic acid. During the SCW decomposition of PE plastics oil or wax, aqueous, gas and solid (only in PE waste) phases were formed. The obtained oil phase was composed of alkanes, alkenes, cycloalkanes, aromatics, and alcohols, while the gas phase manly contained light hydrocarbons (C 1 –C 6). By performing reaction at high temperatures (425–450 °C) and reaction times from 30 to 240 min the concentrations of long-chain hydrocarbons (>C 20) and C 9 –C 20 (diesel) fraction in oil phase decreased, while concentration of C 6 –C 8 hydrocarbons (gasoline fraction) increased. Finally, the influence of acetic acid on the PE degradation has been discussed and the potential degradation mechanism of PE waste in SCW is proposed. [ABSTRACT FROM AUTHOR]

Review summarizes the research on the biomass conversion for production of chemicals and an overview on recent activities of our research group on isolation of substances from biomass using sub- and supercritical water. Herein, hydrothermal processing of biomass waste represents an alternative approach to upswing the productivity chemicals, basic chemicals for synthesis and plant-based pharmaceutical compounds. The processing concepts to obtain products and product classes based on biological raw materials in gaseous, liquid, or solid state are presented. Subcritical water is discussed as a highly reactive media to enhance extraction affinity of value added compounds, such as proteins and amino acids, essential oils, oils and fatty acids, carbohydrates and phenolic compounds from natural sources. [ABSTRACT FROM AUTHOR]