Pyrethroid-Degrading Microorganisms and Their Potential for the Bioremediation of Contaminated Soils: A Review

Abstract

Pyrethroid insecticides have been used to control pests in agriculture, forestry, horticulture, public health and for indoor home use for more than 20 years. Because pyrethroids were considered to be a safer alternative to organophosphate pesticides (OPs), their applications significantly increased when the use of OPs was banned or limited. Although, pyrethroids have agricultural benefits, their widespread and continuous use is a major problem as they pollute the terrestrial and aquatic environments and affect non-target organisms. Since pyrethroids are not degraded immediately after application and because their residues are detected in soils, there is an urgent need to remediate pyrethroid-polluted environments. Various remediation technologies have been developed for this purpose; however, bioremediation, which involves bioaugmentation and/or biostimulation and is a cost-effective and eco-friendly approach, has emerged as the most advantageous method for cleaning-up pesticide-contaminated soils. This review presents an overview of the microorganisms that have been isolated from pyrethroid-polluted sites, characterized and applied for the degradation of pyrethroids in liquid and soil media. The paper is focused on the microbial degradation of the pyrethroids that have been most commonly used for many years such as allethrin, bifenthrin, cyfluthrin, cyhalothrin, cypermethrin, deltamethrin, fenpropathrin, fenvalerate, and permethrin. Special attention is given to the bacterial strains from the genera Achromobacter, Acidomonas, Bacillus, Brevibacterium, Catellibacterium, Clostridium, Lysinibacillus, Micrococcus, Ochrobactrum, Pseudomonas, Serratia, Sphingobium, Streptomyces, and the fungal strains from the genera Aspergillus, Candida, Cladosporium, and Trichoderma, which are characterized by their ability to degrade various pyrethroids. Moreover, the current knowledge on the degradation pathways of pyrethroids, the enzymes that are involved in the cleavage of pesticide molecules, the factors/conditions that influence the survival of strains that are introduced into soil and the rate of the removal of pyrethroids are also discussed. This knowledge may be useful to optimize the environmental conditions of bioremediation and may be crucial for the effective removal of pyrethroids from polluted soils.

New Insights into the Microbial Degradation of D-Cyphenothrin in Contaminated Water/Soil Environments

“…In this study, we identified a novel bacterial isolate S. succinus HLJ-10 having superb D-cyphenothrin degradation activity. Strain HLJ-10 utilized D-cyphenothrin as the sole carbon source for its growth over a wide range of temperature (25-35 • C) and pH (5)(6)(7)(8)(9), indicating that the strain has excellent working ability in adverse environments. This study proves that the bacterium harbors the metabolic pathway for complete detoxification and metabolism of D-cyphenothrin.…”

“…The optimum temperature, pH, and inoculum size at the unencoded levels were found as 31.6 • C, 7.9, and 6.05 × 10 8 CFU·mL −1 , respectively. Strain HLJ-10 was capable of rapidly degrading D-cyphenothrin without a lag phase over a wide range of temperature (25-35 • C) and pH (5)(6)(7)(8)(9). This is a very important feature of an organism for bioremediation of variable environments [30].…”

“…However, persistent use of D-cyphenothrin affects non-target organisms and contaminates terrestrial and aquatic environments [6]. Agricultural countries produce large amounts of agro-wastewater that is directly discharged into natural channels, posing serious environmental effects [7]. In the aqueous phase, D-cyphenothrin is separated from water due to non-polar property and adsorbs in sediments [8].…”

Fitness costs of infection with Serratia symbiotica are associated with greater susceptibility to insecticides in the pea aphid Acyrthosiphon pisum

“…There is emerging evidence that bacteria (including symbionts) are involved in the detoxification or degradation of insecticides, which may help to address pollution issues but on the other side could also promote insecticide resistance. [24][25][26][27][28] Serratia, Burkholderia, Pseudomonas and Flavobacterium spp. can degrade several different classes of insecticides.…”

Molecular Mechanism and Genetic Determinants of Buprofezin Degradation

“…Microbial degradation plays an important role in the elimination of xenobiotics (18). To date, several pure bacterial cultures that are capable of degrading buprofezin have been isolated.…”