PMID- 37659610 OWN - NLM STAT- MEDLINE DCOM- 20230920 LR - 20230920 IS - 1532-0456 (Print) IS - 1532-0456 (Linking) VI - 273 DP - 2023 Nov TI - Cyanobacterial degradation of herbicide 2,4-dichlorophenoxyacetic acid (2,4-D): Its response to the oxidative stress induced by the primary degradation product 2,4-dichlorophenol (2,4-DCP). PG - 109739 LID - S1532-0456(23)00194-1 [pii] LID - 10.1016/j.cbpc.2023.109739 [doi] AB - Excessive use of herbicides in agricultural fields has become a major environmental concern due to the negative effects on the ecosystem. Microbial degradation has been well-known as an effective approach for combating such non-natural substances in soil. In the present study, the degradation of 2,4-Dichlorophenoxyacetic acid (2,4-D) as a result of metabolic activities of a cyanobacterium Nostoc muscorum Meg 1 was investigated using GC-MS analysis. After seven days of 2,4-D exposure, the main residue obtained was 2,4-dichlorophenol (2,4-DCP) at RT: 8.334 (confirmed using NIST library). The effects of 2,4-DCP were studied in a cyanobacterium Nostoc muscorum Meg 1 isolated from a rice field where 2,4-D is commonly used. Exposure to 2,4-DCP at 20, 40, and 80 ppm significantly increased ROS production in the cyanobacterium by 74, 107, and 211 % (p < 0.001). With rising 2,4-DCP concentrations in the surroundings, lipid peroxidation and protein oxidation in the organism correspondingly increased, indicating cellular injury. The mRNA and protein contents, and also the activities of different oxidant neutralizing enzymes such as CAT, SOD, GR, and GPx and the non-enzymatic antioxidants (proline, GSH, thiol and phytochelatin content) were found augmented in 20 ppm 2,4-DCP exposed cultures. However, in the presence of 40 and 80 ppm 2,4-DCP, most enzymatic and non-enzymatic antioxidants were severely compromised. At higher exposures, the organism's attempt to mitigate the oxidants was still visible, as both proline and TSH levels increased. SEM and TEM analysis aided in visualizing the effects of 2,4-DCP on the morphology and ultrastructures of the organism. CI - Copyright (c) 2023 Elsevier Inc. All rights reserved. FAU - Sachu, Meguovilie AU - Sachu M AD - Department of Biochemistry, North-Eastern Hill University, Shillong 793022, Meghalaya, India. FAU - Kynshi, Balakyntiewshisha Lyngdoh AU - Kynshi BL AD - Department of Biochemistry, North-Eastern Hill University, Shillong 793022, Meghalaya, India. FAU - Syiem, Mayashree B AU - Syiem MB AD - Department of Biochemistry, North-Eastern Hill University, Shillong 793022, Meghalaya, India. Electronic address: mayashreesyiem@yahoo.co.in. LA - eng PT - Journal Article DEP - 20230901 PL - United States TA - Comp Biochem Physiol C Toxicol Pharmacol JT - Comparative biochemistry and physiology. Toxicology & pharmacology : CBP JID - 100959500 RN - 0 (Antioxidants) RN - 0 (Herbicides) RN - R669TG1950 (2,4-dichlorophenol) RN - 0 (Oxidants) RN - 0 (Phenols) RN - 0 (Phenoxyacetates) RN - 9DLQ4CIU6V (Proline) RN - 2577AQ9262 (2,4-Dichlorophenoxyacetic Acid) SB - IM MH - Antioxidants MH - *Herbicides/toxicity MH - Ecosystem MH - Bacteria MH - Oxidative Stress MH - *Nostoc muscorum MH - Oxidants MH - Phenols MH - Phenoxyacetates MH - Proline MH - 2,4-Dichlorophenoxyacetic Acid/toxicity OTO - NOTNLM OT - 2,4-D OT - 2,4-DCP OT - Antioxidants OT - Cyanobacteria OT - GC-MS COIS- 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. EDAT- 2023/09/03 00:41 MHDA- 2023/09/20 06:42 CRDT- 2023/09/02 19:26 PHST- 2023/05/22 00:00 [received] PHST- 2023/08/21 00:00 [revised] PHST- 2023/08/30 00:00 [accepted] PHST- 2023/09/20 06:42 [medline] PHST- 2023/09/03 00:41 [pubmed] PHST- 2023/09/02 19:26 [entrez] AID - S1532-0456(23)00194-1 [pii] AID - 10.1016/j.cbpc.2023.109739 [doi] PST - ppublish SO - Comp Biochem Physiol C Toxicol Pharmacol. 2023 Nov;273:109739. doi: 10.1016/j.cbpc.2023.109739. Epub 2023 Sep 1.