Dataset Information

Paraquat Degradation by Biological Manganese Oxide (BioMnO x ) Catalyst Generated From Living Microalga Pediastrum duplex AARL G060.

ABSTRACT: Paraquat is a non-selective fast-acting herbicide used to control weeds in agricultural crops. Many years of extensive use has caused environmental pollution and food toxicity. This agrochemical degrades slowly in nature, adsorbs onto clay lattices, and may require environmental remediation. Studies have shown that biosynthesized manganese oxide (BioMnOx) successfully degraded toxic synthetic compounds such as bis-phenol A and diclofenac, thus it has potential for paraquat degradation. In this experiment, P. duplex AARL G060 generated low (9.03 mg/L) and high (42.41 mg/L) concentrations of BioMnOx. The precipitated BioMnOx was observed by scanning electron microscopy (SEM), and the elemental composition was identified as Mn and O by energy-dispersive x-ray spectroscopy (EDS). The potential for BioMnOx to act as a catalyst in the degradation of paraquat was evaluated under three treatments: (1) a negative control (deionized water), (2) living alga with low BioMnOx plus hydrogen peroxide, and (3) living alga with high BioMnOx plus hydrogen peroxide. The results indicate that BioMnOx served as a catalyst in the Fenton-like reaction that could degrade more than 50% of the paraquat within 72 h. A kinetic study indicated that paraquat degradation by Fenton-like reactions using BioMnOx as a catalyst can be described by pseudo-first and pseudo-second order models. The pH level of the BioMnOx catalyst was neutral at the end of the experiment. In conclusion, BioMnOx is a viable and environmentally friendly catalyst to accelerate degradation of paraquat and other toxic chemicals.

SUBMITTER: Thongpitak J

PROVIDER: S-EPMC7522373 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Paraquat Degradation by Biological Manganese Oxide (BioMnO x ) Catalyst Generated From Living Microalga Pediastrum duplex AARL G060.

Thongpitak Jakkapong J Pumas Pamon P Pumas Chayakorn C

Frontiers in microbiology 20200915

Paraquat is a non-selective fast-acting herbicide used to control weeds in agricultural crops. Many years of extensive use has caused environmental pollution and food toxicity. This agrochemical degrades slowly in nature, adsorbs onto clay lattices, and may require environmental remediation. Studies have shown that biosynthesized manganese oxide (BioMnOx) successfully degraded toxic synthetic compounds such as bis-phenol A and diclofenac, thus it has potential for paraquat degradation ...[more]

PMID: 33042090

Similar Datasets

Project description:Acidification occurs as a result of acid mine drainage after the oxidative weathering of metal sulfides. The acidic condition corrodes other toxic elements from the soil and becomes distributed around the operating site. Although coal mines go through a process of rehabilitation, water samples in the rehabilitated reservoir still reveal high concentrations of certain metals, for example, manganese (Mn). Both living and non-living biomass substances were used in Mn remediation. However, using non-living biomass as a sorbent may be inappropriate for the purposes of upscaling in high-volume water bodies. Thus, living microalga, Pediastrum duplex AARLG060, has become of significant interest for this type of application. The Mn remediation of microalga was performed by biosorption and bio-oxidation. The aim of this study was to evaluate the potential of microalgal Mn remediation of the water obtained from a rehabilitated coal-mine reservoir. The equilibrium and isotherm values of the remediation process were also studied. The microalga was used to remediate Mn in water under three different water conditions, including filtrated water obtained from the rehabilitated site, non-filtrated water that was sterilized with an autoclave, and non-treated water. Remediation was performed by culturing microalga with modified medium consisting of N, P, C, and Mg nutrients. The remediated Mn concentration present in the cultures was detected by atomic absorption spectroscopy. The precipitated Mn was collected as a result of bio-oxidation, and EDTA was used to wash Mn from the biomass. This was designated as an adsorption result. Characterization of biosorption was evaluated by employing the Langmuir and Freundlich models. The results demonstrated that all treatments of living microalga could support Mn bio-oxidation. The Mn remediation was successfully performed at over 97% in every treatment. The adsorption characteristics revealed a close similarity to the Langmuir isotherm of monolayer adsorption. The scanning electron microscope-energy dispersive spectroscopy (SEM-EDS) indicated precipitation of Mn oxide on the cell surface, while transmission electron microscopy (TEM) revealed that the nanoparticles of Mn were scattered mainly in the chloroplast and throughout the vacuoles of the cells.

Project description:BACKGROUND:Comparative studies of chloroplast genomes (plastomes) across the Chlorophyceae are revealing dynamic patterns of size variation, gene content, and genome rearrangements. Phylogenomic analyses are improving resolution of relationships, and uncovering novel lineages as new plastomes continue to be characterized. To gain further insight into the evolution of the chlorophyte plastome and increase the number of representative plastomes for the Sphaeropleales, this study presents two fully sequenced plastomes from the green algal family Hydrodictyaceae (Sphaeropleales, Chlorophyceae), one from Hydrodictyon reticulatum and the other from Pediastrum duplex. METHODS:Genomic DNA from Hydrodictyon reticulatum and Pediastrum duplex was subjected to Illumina paired-end sequencing and the complete plastomes were assembled for each. Plastome size and gene content were characterized and compared with other plastomes from the Sphaeropleales. Homology searches using BLASTX were used to characterize introns and open reading frames (orfs) ≥ 300 bp. A phylogenetic analysis of gene order across the Sphaeropleales was performed. RESULTS:The plastome of Hydrodictyon reticulatum is 225,641 bp and Pediastrum duplex is 232,554 bp. The plastome structure and gene order of H. reticulatum and P. duplex are more similar to each other than to other members of the Sphaeropleales. Numerous unique open reading frames are found in both plastomes and the plastome of P. duplex contains putative viral protein genes, not found in other Sphaeropleales plastomes. Gene order analyses support the monophyly of the Hydrodictyaceae and their sister relationship to the Neochloridaceae. DISCUSSION:The complete plastomes of Hydrodictyon reticulatum and Pediastrum duplex, representing the largest of the Sphaeropleales sequenced thus far, once again highlight the variability in size, architecture, gene order and content across the Chlorophyceae. Novel intron insertion sites and unique orfs indicate recent, independent invasions into each plastome, a hypothesis testable with an expanded plastome investigation within the Hydrodictyaceae.

Project description:Exposures to high doses of manganese (Mn) via inhalation, dermal contact or direct consumption can cause adverse health effects. Welding fumes are a major source of manganese containing nanoparticles in occupational settings. Understanding the physicochemical properties of manganese-containing nanoparticles can be a first step in understanding their toxic potential following exposure. In particular, here we compare the size, morphology and Mn oxidation states of Mn oxide nanoparticles generated in the laboratory by arc discharge to those from welding collected in heavy vehicle manufacturing. Fresh nanoparticles collected at the exit of the spark discharge generation chamber consisted of individual or small aggregates of primary particles. These nanoparticles were allowed to age in a chamber to form chain-like aggregates of primary particles with morphologies very similar to welding fumes. The primary particles were a mixture of hausmannite (Mn3O4), bixbyite (Mn2O3) and manganosite (MnO) phases, whereas aged samples revealed a more amorphous structure. Both Mn2+ and Mn3+, as in double valence stoichiometry present in Mn3O4, and Mn3+, as in Mn2O3 and MnOOH, were detected by X-ray photoelectron spectroscopy on the surface of the nanoparticles in the laboratory nanoparticles and welding fumes. Dissolution studies conducted for these two Mn samples (aged and fresh fume) reveal different release kinetics of Mn ions in artificial lysosomal fluid (pH 4.5) and very limited dissolution in Gamble's solution (pH 7.4). Taken together, these data suggest several important considerations for understanding the health effects of welding fumes. First, the method of particle generation affects the crystallinity and phase of the oxide. Second, welding fumes consist of multiple oxidation states whether they are amorphous or crystalline or occur as isolated nanoparticles or agglomerates. Third, although the dissolution behavior depends on conditions used for nanoparticle generation, the dissolution of Mn oxide nanoparticles in the lysosome may promote Mn ions translocation into various organs causing toxic effects.

Dataset Information

Paraquat Degradation by Biological Manganese Oxide (BioMnO x ) Catalyst Generated From Living Microalga Pediastrum duplex AARL G060.

Publications

Paraquat Degradation by Biological Manganese Oxide (BioMnO <sub><i>x</i></sub> ) Catalyst Generated From Living Microalga <i>Pediastrum duplex</i> AARL G060.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets