Proteins are a widely available biomass source for synthesizing strong and tough engineering polymers because of their propensity to hydrogen bond, chemically stable amide backbone, and demonstrated efficacy at forming relevant material structures in nature. Because the properties of polypeptides in many ways mimic urethane bonds and hard domains, herein proteins are explored as the reinforcing component in a polyurethane-inspired elastomer. Materials are synthesized using a two-step process: first, protein is methacrylated, and then copolymerized with (meth)acrylate comonomers to link protein domains with rubbery polymer chains. This is demonstrated with water-soluble proteins, whey protein and β-lactoglobulin, and a comonomer, hydroxypropyl acrylate (HPA). The resulting elastomers are amorphous and disordered but have microphase-separated morphologies. Materials with a wide range of stiffnesses have been prepared by varying the fraction of protein macro-cross-linkers in the materials. The protein aggregates function like fillers that strengthen the materials, which are shown to be tougher than both unreinforced homopolymers and unmodified proteins. Materials with low cross-link densities prepared using proteins modified at low methacrylation levels are also stiffer than protein−polymer blends. Above an optimal protein methacrylation level, increasing chemical cross-link densities led to lower extents of protein aggregation and decreased moduli.

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Implementing microalgae biorefinery in arid environments requires utilization of strains that can grow at high temperatures (above 28 °C) and salinity levels (above 30 ppt). In this study, we investigate the newly isolated seawater strain, Synechococcus, native to the United Arab Emirates, and evaluate its value as a perspective organism for cultivation (for fuel and bio-products) in regions with freshwater scarcity. The strain displayed tolerance to a wide range of temperature (22–37 °C) and salinity (20–41 ppt), with maximum biomass concentration of 0.72 g L−1 and a maximum growth rate of 82 mg L−1 d−1 at 25 °C and 33 ppt salinity. Lipids accumulation reached up to 26% of dry weight in nitrogen-depleted conditions (with 1.8 mM of nitrates addition to the media), whereas protein content exceeded 50% dry weight. In this study, harvesting is investigated using three chemical agents: Ferric chloride, sodium hydroxide, and chitosan. Cell disruption is analyzed for four distinct treatments: Enzymatic, alkaline, ultrasonic, and hydrothermal. Among tested methods, flocculation with sodium hydroxide and ultrasonication were found to be the most efficient techniques for harvesting and cell disruption, respectively. The growth characteristics of the local strain and the potential to derive protein and lipids from it makes it a promising biomass in a biorefinery context.