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Nowadays, the environmental pollution caused by conventional petroleum‐based plastics is one of the most serious problems facing mankind, and it is of great significance to look for alternative plastics with biodegradable feature. Notably, the bioplastics based on polyhydroxyalkanoates (PHA) have been a focus on research and development during the past several decades. In this review, the recent advances on the biological production of PHA were summarized, mainly including biosynthetic pathways and methods, followed by the extraction processes. Furthermore, the current status on PHA production using industrial waste streams was also discussed. For the moment, the relative higher production cost hindered the large‐scale biological production of PHA. Therefore, some insightful strategies were presented about the future research and scale production on biological production of PHA.

Conventional separation membranes suffer from evitable fouling and flux decrease for water treatment applications. Herein, a novel protocol of electro-enhanced membrane separation is proposed for the efficient treatment of microsized emulsions (∼1 μm) by rationally designing robust electroresponsive copper metallic membranes, which could mitigate oil fouling and coenhance permeance (from ∼1026 to ∼2516 L·m–2·h–1·bar–1) and rejection (from ∼87 to ∼98%). High-flux Cu membranes exhibit superior ductility and electrical conductivity, enabling promising electroactivity. Separation performance and the fouling mechanism were studied under different electrical potentials and ionic strengths. Application of negative polarization into a large-pore (∼2.1 μm) Cu membrane is favorable to not only almost completely reject smaller-sized oil droplets (∼1 μm) but also achieve antifouling and anticorrosion functions. Moreover, surfactants around oil droplets might be redistributed due to electrostatic repulsion, which effectively enhances the steric hindrance effect between neighboring oil droplets, mitigating oil coalescence and consequently membrane fouling. Furthermore, due to the screening effect of surfactants, the presence of low-concentration salts increases the adsorption of surfactants at the oil–water interface, thus preventing oil coalescence via decreasing oil–water interfacial tension. However, under high ionic strengths, the fouling mechanism converts from cake filtration to a complete blocking model due to the reduced electrostatic repulsion between the Cu membrane and oil droplets. This work would provide mechanistic insights into electro-enhanced antifouling for not only oil emulsion separation but also more water treatment applications using rationally designed novel electroresponsive membranes.

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