The pyrethroid (+/-)-lambda-cyhalothrin enantioselective biodegradation by a bacterial consortium

Author(s)

Birolli, Willian G. ^[1] ; Arai, Marylyn S. ^[1] ; Nitschke, Marcia ^[2] ; Porto, Andre L. M. ^[1]

Affiliation

^[1] Univ Sao Paulo, Inst Quim Sao Carlos, Lab Quim Organ & Biocatalise, Av Joao Dagnone 1100, Ed Quim Ambiental, BR-13563120 Sao Carlos, SP - Brazil

^[2] Univ Sao Paulo, Inst Quim Sao Carlos, Lab Biotecnol Microbiana, Av Joao Dagnone 1100, Ed Quim Ambiental, BR-13563120 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY; v. 156, p. 129-137, MAY 2019.
• Web of Science Citations: 2

Abstract

Chiral pesticides have been used in agriculture, including (+/-)-lambda-cyhalothrin ((+/-)-LC), which is a pyrethroid insecticide widely employed on crops for protection against different types of insects. However, enantioselectivity is poorly studied in biodegradation processes. Therefore, the (+/-)-LC enantioselective biodegradation by bacteria from Brazilian savannah was reported in this study with a validated analytical method. All bacterial strains biodegraded (+/-)-LC with different efficiencies. Residual concentrations of LC (3.7-43.1% of biodegradation) and its enantiomeric excesses (0-27% ee) were determined. Additionally, the formation of the main biodegradation metabolite 3-phenoxybenzoic acid was also quantified. A Bacillus consortium composed of the three most efficient strains biodegraded more LC than any isolated strain solely employed in this work, showing that the use of a consortium is an interesting approach. In addition, 13 metabolites were identified and a biodegradation pathway with biochemical reactions of hydrolysis, reduction, esterification, amidation, elimination and group transfer were proposed, confirming the bioremediation potential of these strains. The LC stereoisomer with the highest insecticidal activity (1R,3R,alpha S-enantiomer, also known as gamma-cyhalothrin) was preferentially biodegraded by the studied bacteria. Therefore, crops protection with gamma-cyhalothrin, which can be applied in lower concentrations than (+/-)-LC because it is a more effective product against insects, may also be biodegraded faster than the racemic mixture in the environment, decreasing the toxic effects on non target organisms. (AU)

• FAPESP's process: 12/19934-0 - Biodegradation of pesticides by microorganisms (fungi and bacteria)
• Grantee: Andre Luiz Meleiro Porto
• Support type: Regular Research Grants
• FAPESP's process: 14/08558-3 - Enantioselective Biodegradation of the Pyrethroid Pesticide (±)-Lambda-Cyhalothrin by Environmental Bacteria
• Grantee: Marylyn Setsuko Arai
• Support type: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 17/19721-0 - USE OF ENVIRONMENTAL MICRORGANISMS IN THE BIODEGRADATION OF STROBILURINIC AND PYRETHROIDS PESTICIDES WIDELY EMPLOYED IN THE BRAZILIAN AGRICULTURE
• Grantee: Willian Garcia Birolli
• Support type: Scholarships in Brazil - Post-Doctorate
• FAPESP's process: 14/18257-0 - New approaches in biocatalytic reactions
• Grantee: Andre Luiz Meleiro Porto
• Support type: Regular Research Grants