Degradation of Carbendazim by Molecular Hydrogen on Leaf Models

Microbes as carbendazim degraders: opportunity and challenge

Carbendazim (methyl benzimidazol-2-ylcarbamate, CBZ) is a systemic benzimidazole carbamate fungicide and can be used to control a wide range of fungal diseases caused by Ascomycetes, Basidiomycetes and Deuteromycetes. It is widely used in horticulture, forestry, agriculture, preservation and gardening due to its broad spectrum and leads to its accumulation in soil and water environmental systems, which may eventually pose a potential threat to non-target organisms through the ecological chain. Therefore, the removal of carbendazim residues from the environment is an urgent problem. Currently, a number of physical and chemical treatments are effective in degrading carbendazim. As a green and efficient strategy, microbial technology has the potential to degrade carbendazim into non-toxic and environmentally acceptable metabolites, which in turn can dissipate carbendazim from the contaminated environment. To date, a number of carbendazim-degrading microbes have been isolated and reported, including, but not limited to, Bacillus, Pseudomonas, Rhodococcus, Sphingomonas, and Aeromonas. Notably, the common degradation property shared by all strains was their ability to hydrolyze carbendazim to 2-aminobenzimidazole (2-AB). The complete mineralization of the degradation products is mainly dependent on the cleavage of the imidazole and benzene rings. Additionally, the currently reported genes for carbendazim degradation are MheI and CbmA, which are responsible for breaking the ester and amide bonds, respectively. This paper reviews the toxicity, microbial degradation of carbendazim, and bioremediation techniques for carbendazim-contaminated environments. This not only summarizes and enriches the theoretical basis of microbial degradation of carbendazim, but also provides practical guidance for bioremediation of carbendazim-contaminated residues in the environment.

The function of microbial enzymes in breaking down soil contaminated with pesticides: a review

The use of pesticides and the subsequent accumulation of residues in the soil has become a worldwide problem. Organochlorine (OC) pesticides have spread widely in the environment and caused contamination from past agricultural activities. This article reviews the bioremediation of pesticide compounds in soil using microbial enzymes, including the enzymatic degradation pathway and the recent development of enzyme-mediated bioremediation. Enzyme-mediated bioremediation is divided into phase I and phase II, where the former increases the solubility of pesticide compounds through oxidation-reduction and hydrolysis reactions, while the latter transforms toxic pollutants into less toxic or nontoxic products through conjugation reactions. The identified enzymes that can degrade OC insecticides include dehalogenases, phenol hydroxylase, and laccases. Recent developments to improve enzyme-mediated bioremediation include immobilization, encapsulation, and protein engineering, which ensure its stability, recyclability, handling and storage, and better control of the reaction.

Editorial for Special Issue: “Production and Role of Molecular Hydrogen in Plants”

Molecular hydrogen (H2) is an extremely small molecule, which is relatively insoluble in water and relatively inert [...]