Elucidating molecular characterization of chlorpyrifos and profenofos degrading distinct bacterial strains for enhancing seed germination potential of Gossypium arboreum L

An ultra-sensitive photoelectrochemical biosensing platform based on the AgVO3/BiOI heterojunction for an enzyme activity inhibition reaction

An ultra-sensitive photoelectrochemical sensing platform for profenofos detection based on the inhibition of catalase activity was prepared in this work. First, the novel functional nanocomposite material AgVO3/BiOI was prepared by a hot solvent method and successive ion layer adsorption reaction. Then, chitosan was employed as a dispersion medium to disperse and immobilize the catalase. Under visible light irradiation, the prepared CAT/CS/AgVO3/BiOI/ITO nanocomposite electrode generates a stable low photocurrent in hydrogen peroxide solution. When this electrode is immersed in a phosphate buffer solution containing profenofos, the activity of the catalase is inhibited, resulting in an increase in the photocurrent. Under the optimized experimental conditions, the profenofos concentration and increase in photocurrent are linearly related in the concentration range of 1 × 10-10 to 5.0 × 10-8 mol L-1, and the limit of detection is 1.0 × 10-11 mol L-1. This biosensor shows good selectivity for detecting profenofos in fruits and vegetables, and the determination results of profenofos are satisfactory.

Microbial detoxification of chlorpyrifos, profenofos, monocrotophos, and dimethoate by a multifaceted rhizospheric Bacillus cereus strain PM38 and its potential for the growth promotion in cotton

Bacillus genera, especially among rhizobacteria, are known for their ability to promote plant growth and their effectiveness in alleviating several stress conditions. This study aimed to utilize indigenous Bacillus cereus PM38 to degrade four organophosphate pesticides (OPs) such as chlorpyrifos (CP), profenofos (PF), monocrotophos (MCP), and dimethoate (DMT) to mitigate the adverse effects of these pesticides on cotton crop growth. Strain PM38 exhibited distinct characteristics that set it apart from other Bacillus species. These include the production of extracellular enzymes, hydrogen cyanide, exopolysaccharides, Indol-3-acetic acid (166.8 μg/mL), siderophores (47.3 μg/mL), 1-aminocyclopropane-1-carboxylate deaminase activity (32.4 μg/mL), and phosphorus solubilization (162.9 μg/mL), all observed at higher concentrations. This strain has also shown tolerance to salinity (1200 mM), drought (20% PEG-6000), and copper and cadmium (1200 mg/L). The amplification of multi-stress-responsive genes, such as acdS, ituC, czcD, nifH, sfp, and pqqE, further confirmed the plant growth regulation and abiotic stress tolerance capability in strain PM38. Following the high-performance liquid chromatography (HPLC) analysis, the results showed striking compatibility with the first kinetic model. Strain PM38 efficiently degraded CP (98.4%), PF (99.7%), MCP (100%), and DMT (95.5%) at a concentration of 300 ppm over 48 h at 35 °C under optimum pH conditions, showing high coefficients of determination (R2) of 0.974, 0.967, 0.992, and 0.972, respectively. The Fourier transform infrared spectroscopy (FTIR) analysis and the presence of opd, mpd, and opdA genes in the strain PM38 further supported the potential to degrade OPs. In addition, inoculating cotton seedlings with PM38 improved root length under stressful conditions. Inoculation of strain PM38 reduces stress by minimizing proline, thiobarbituric acid-reactive compounds, and electrolyte leakage. The strain PM38 has the potential to be a good multi-stress-tolerant option for a biological pest control agent capable of improving global food security and managing contaminated sites.

Deciphering the mechanistic role of Bacillus paramycoides (PM51) and Bacillus tequilensis (PM52) in bio-sorption and phyto-assimilation of Cadmium via Linum usitatissimum L. Seedlings

Three Cd2+ resistant bacterium's minimal inhibition concentrations were assessed and their percentages of Cd2+ accumulation were determined by measurements using an atomic absorption spectrophotometer (AAS). The results revealed that two isolates Bacillus paramycoides (PM51) and Bacillus tequilensis (PM52), identified by 16S rDNA gene sequencing, showed a higher percentage of Cd2+ accumulation i.e., 83.78% and 81.79%, respectively. Moreover, both novel strains can tolerate Cd2+ levels up to 2000 mg/L isolated from district Chakwal. Amplification of the czcD, nifH, and acdS genes was also performed. Batch bio-sorption studies revealed that at pH 7.0, 1 g/L of biomass, and an initial 150 mg/L Cd2+ concentration were the ideal bio-sorption conditions for Bacillus paramycoides (PM51) and Bacillus tequilensis (PM52). The experimental data were fit to Langmuir isotherm measurements and Freundlich isotherm model R2 values of 0.999 for each of these strains. Bio sorption processes showed pseudo-second-order kinetics. The intra-diffusion model showed Xi values for Bacillus paramycoides (PM51) and Bacillus tequilensis (PM52) of 2.26 and 2.23, respectively. Different surface ligands, was investigated through Fourier-transformation infrared spectroscopy (FTIR). The scanning electron microscope SEM images revealed that after Cd2+ adsorption, the cells of both strains became thick, adherent, and deformed. Additionally, both enhanced Linum usitatissimum plant seed germination under varied concentrations of Cd2+ (0 mg/L, 250 mg/L,350 mg/L, and 500 mg/L). Current findings suggest that the selected strains can be used as a sustainable part of bioremediation techniques.

Unlocking the interaction of organophosphorus pesticide residues with ecosystem: Toxicity and bioremediation

Organophosphorus adulteration in the environment creates terrestrial and aquatic pollution. It causes acute and subacute toxicity in plants, humans, insects, and animals. Due to the excessive use of organophosphorus pesticides, there is a need to develop environmentally friendly, economical, and bio-based strategies. The microbiomes, that exist in the soil, can reduce the devastating effects of organophosphates. The use of cell-free enzymes and yeast is also an advanced method for the degradation of organophosphates. Plant-friendly bacterial strains, that exist in the soil, can help to degrade these contaminants by oxidation-reduction reactions, enzymatic breakdown, and adsorption. The bacterial strains mostly from the genus Bacillus, Pseudomonas, Acinetobacter, Agrobacterium, and Rhizobium have the ability to hydrolyze the bonds of organophosphate compounds like profenofos, quinalphos, malathion, methyl-parathion, and chlorpyrifos. The native bacterial strains also promote the growth abilities of plants and help in detoxification of organophosphate residues. This bioremediation technique is easy to use, relatively cost-effective, very efficient, and ensures the safety of the environment. This review covers the literature gap by describing the major effects of organophosphates on the ecosystem and their bioremediation by using native bacterial strains.

The looming threat of profenofos organophosphate and microbes in action for their sustainable degradation

Organophosphates are the most extensively used class of pesticides to deal with increasing pest diversity and produce more on limited terrestrial areas to feed the ever-expanding global population. Profenofos, an organophosphate group of non-systematic insecticides and acaricides, is used to combat aphids, cotton bollworms, tobacco budworms, beet armyworms, spider mites, and lygus bugs. Profenofos was inducted into the system as a replacement for chlorpyrifos due to its lower toxicity and half-life. It has become a significant environmental concern due to its widespread presence. It accumulates in various environmental components, contaminating food, water, and air. As a neurotoxic poison, it inhibits acetylcholinesterase receptor activity, leading to dizziness, paralysis, and pest death. It also affects other eukaryotes, such as pollinators, birds, mammals, and invertebrates, affecting ecosystem functioning. Microbes directly expose themselves to profenofos and adapt to these toxic compounds over time. Microbes use these toxic compounds as carbon and energy sources and it is a sustainable and economical method to eliminate profenofos from the environment. This article explores the studies and developments in the bioremediation of profenofos, its impact on plants, pollinators, and humans, and the policies and laws related to pesticide regulation. The goal is to raise awareness about the global threat of profenofos and the role of policymakers in managing pesticide mismanagement.

Magnetic-assisted exciton-plasmon interactions modulated Bi2S3 nanorods@MoS2 nanosheets heterojunction: towards a split-type photoelectrochemical sensing of profenofos

A split-type photoelectrochemical (PEC) sensor was designed for the detection of profenofos (PFF) depending on the magnetic-assisted exciton-plasmon interactions (EPI) between the semiconductor substrate and Au NPs. The core-shell Bi2S3 nanorods@MoS2 nanosheets (Bi2S3 NRs@MoS2 NSs) heterostructure nanomaterial with fascinating performance was synthesized and used as the photovoltaic conversion substrate and signal molecules absorption platform. The PEC sensor is operated by co-incubating with the released Au NPs-cDNA from the surface of magnetic beads, originating from the target-triggered DNA double-stranded structure opening event. Due to the strong EPI effects, the photocurrent of Bi2S3 NRs@MoS2 NSs decreased and varied with the PFF concentrations. The proposed PEC sensor exhibited outstanding analytical performances, including a wide linear range (1.0 pg mL-1~1.0 μg mL-1), low detection limitation (0.23 pg mL-1, at 3 σ/m), excellent specificity, high stability, and applicability. Overall, this work provides a new signal strategy for PEC biosensors and extends its application in environmental analysis.