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With global enforcement of plastic bans and restrictions, the biodegradable plastic, e.g., polylactic acid (PLA), has been extensively employed as a primary substitute for traditional petroleum-based plastics. However, the growing problem associated with PLA waste accumulation is posing grand environmental challenges. In addition, although PLA has the degrading property under natural conditions, the degradation process takes too long and the degradation products cannot be recycled. In this context, enzymatic degradation of PLA arouses great attention in scientific communities. This study aims at selecting the most cost-effective protease from various enzymes and optimizing the enzymolysis conditions towards the degradation of PLA. We will demonstrate that under an optimal temperature of 45 °C, a pH vale of 11, and an enzyme concentration of 0.6 mg mL -1 , the protease K would achieve a remarkable degradation efficiency (> 99 %) for PLA films within just 50 min. Finally, molecular dynamics (MD) simulation and molecular docking studies reveal the mechanism behind the protease-induced PLA degradation, providing a promising direction for waste treatment and resource utilization for future biodegradable plastics., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

In this context, a novel recycling strategy for the upcycling of waste biodegradable plastics, specifically PBAT, has been proposed. This approach initially employs a 1,4-butanediol-alkali method to rapidly hydrolyze PBAT without introducing other impurities. Following this, a two-step synthesis process is employed to swiftly create a foam nickel-supported NiOOH electrocatalyst. This catalyst efficiently converts the hydrolyzed solution of 1,4-butanediol into the higher-value product, succinic acid, achieving a Faraday efficiency of 97.6% along with satisfactory stability. [Display omitted] • A novel method was employed for the rapid catalytic degradation of PBAT. • A versatile foam nickel-supported NiOOH electrocatalyst was synthesized quickly. • The conversion of PBAT hydrolysis solution into high-value succinic acid. • The oxidative mechanism of 1,4-butanediol by the catalyst was elucidated. Biodegradable plastics such as Poly (butylene adipate-co-terephthalate) (PBAT) have been extensively utilized in numerous fields. However, post-consumption, PBAT tends to pollute the environment and waste resources. Herein, a novel approach employing a 1,4-butanediol-alkali combined method for the hydrolysis of PBAT is introduced. At 130 °C, with a reaction time of 60 min, the hydrolysis rate of PBAT exceeds 99 %. Subsequently, a two-step synthesis rapidly produces a foam nickel-supported NiOOH catalyst for the electrocatalytic reformation of the PBAT hydrolysate into higher-value chemicals (succinate salts) at an impressive current density of 100 mA cm−2 at 1.43 V (vs. RHE) and a Faradaic efficiency of 97.6 %. Experimental results and density functional theory calculations have elucidated the active state changes of the foam nickel-supported NiOOH catalyst and the intermediates in the oxidation of 1,4-butanediol to succinate, alongside the reaction mechanism. This study offers a viable approach for the degradation of PBAT plastic through a 1,4-butanediol-alkali method and the rapid preparation of a foam nickel-supported NiOOH electrocatalyst, achieving the upgraded recycling of post-consumer biodegradable PBAT plastic. [ABSTRACT FROM AUTHOR]