Trends and thresholds on bacterial degradation of bisphenol-A endocrine disruptor - a concise review

Biodegradation of chemical contamination by lactic acid bacteria: A biological tool for food safety

Chemical pollutants such as mycotoxins and pesticides exert harmful effects on human health such as inflammation, oxidative stress, and cancer. Several strategies were applied for food decontamination, including physicochemical and biological strategies. The present review comprehensively discussed the recent efforts related to the biodegradation of eight food chemical contaminants, including mycotoxins, acrylamide, biogenic amines, N-nitrosamines, polycyclic aromatic hydrocarbons, bisphenol A, pesticides, and heavy metals by lactic acid bacteria (LAB). Biological detoxification by LAB such as Lactobacillus is a promising approach to remove the risks related to the presence of chemical and environmental pollutants in foodstuffs. It is a safe, efficient, environmentally friendly, and low-cost strategy to remove hazardous compounds. LAB can directly decrease these chemical pollutants by degradation or adsorption. Also, it can indirectly reduce the content of these pollutants by reducing their precursors. Hence, LAB can contribute to reducing chemical pollutants in contaminated foods and enhance food safety.

Comparative analysis of the antimicrobial activity and dye degradation of metal oxides (TiO2, CdO, Mn2O3, and ZnO) nanoparticles using a green approach

A tremendous amount of recent work has been done on different metal oxide nanomaterials for biological activities and photocatalytic dye degradation. This work used the Cissus quadrangularis leaf extract to prepare TiO2, CdO, Mn2O3, and ZnO nanoparticles using a green synthesis approach. To ascertain the physicochemical characteristics of the generated metal oxide nanoparticles, various characterisation techniques were used. The X-ray diffraction technique was used to determine the composition of the crystal and phase. Metal oxide nanoparticles have been proven to be present through surface morphological investigations using a scanning electron microscope and energy dispersive spectroscopy analysis. UV-Vis and Fourier transform infrared spectra were used for spectroscopic analysis. X-ray photoelectron spectroscopy can determine a material's elemental composition in addition to the electronic and chemical states of its atoms. The nanomaterial's distinct morphology, which resembles rods, rose petals, platelets, and spheres, was discovered by scanning electron microscope. Synthesized metal oxide nanoparticles have demonstrated a remarkable efficiency of 87.5-90.6% when utilized as a catalyst towards the removal of the malachite green dye under UV light irradiation. Additionally, we use the disc diffusion method to assess antibiotic efficacy against Bacillus subtilis, Candida tropicalis, and Escherichia coli. ZnO nanoparticles had the greatest zones of inhibition for 80 μL doses, measuring 26.99 mm for Bacillus subtilis, 27.57 mm for Escherichia coli, and 25.28 mm for Candida tropicalis. The antimicrobial activity was strongly impacted by the size of the nanoparticles and increased with decreasing particle size. Overall, our research demonstrates that metal oxide nanoparticles are a promising photocatalytic agent for wastewater treatment and biological applications.

Bacterial bioremediation as a sustainable strategy for the mitigation of Bisphenol-A

In the era dominated by plastic, the widespread use of plastic in our daily lives has led to a growing accumulation of its degraded byproducts, such as microplastics and plastic additives like Bisphenol A (BPA). BPA is recognized as one of the earliest man-made substances that exhibit endocrine-disrupting properties. It is frequently employed in the manufacturing of epoxy resins, polycarbonates, dental fillings, food storage containers, infant bottles, and water containers. BPA is linked to a range of health issues including obesity, diabetes, chronic respiratory illnesses, cardiovascular diseases, and reproductive abnormalities. This study examines the bacterial bioremediation of the BPA, which is found in many sources and is known for its hazardous effects on the environment. The metabolic pathways for the breakdown of BPA in important bacterial strains were hypothesized based on the observed altered intermediate metabolites during the degradation of BPA. This review discusses the enzymes and genes involved in the bacterial degradation of BPA. The utilization of naturally occurring microorganisms is the most efficient and cost-effective method due to their selectivity of strains, ensuring sustainability.

Research Progress of Methods for Degradation of Bisphenol A

Bisphenol A (BPA), an endocrine disruptor widely used in industrial production, is found in various environmental sources. Despite numerous reports on BPA degradation and removal, the details remain unclear. This paper aims to address this gap by providing a comprehensive review of BPA degradation methods, focusing on biological, physical, and chemical treatments and the factors that affect the degradation of BPA. Firstly, the paper uses VOSviewer software (version 1.6.15) to map out the literature on BPA degradation published in the past 20 years, which reveals the trends and research focus in this field. Next, the advantages and limitations of different BPA degradation methods are discussed. Overall, this review highlights the importance of BPA degradation to protect the environment and human health. The paper provides significant insights for researchers and policymakers to develop better approaches for BPA degradation and removal.

Application of iron-intercalated graphite for modification of nickel foam cathode in heterogeneous electro-Fenton system: Bisphenol A removal from water at neutral pH

The presence of bisphenol A (BPA) in natural waters can be highly harmful due to its high persistence and adverse effects, raising concerns to remove this hazardous compound. Herein, an electro-Fenton system is proposed to eliminate BPA, wherein the iron source in the Fenton reaction is provided by its intercalation into the carbon layers of graphite. The produced heterogeneous catalyst was then coated onto the nickel foam serving as a cathode. The magnetic graphite intercalated compound (mGIC) and the modified cathode (before and after experiments) were characterized by FE-SEM, EDX, XPS, and XRD analyses. Some effective parameters, namely pH (3-9), current density (0-20 mA cm-2), and BPA concentration (0.5-20 mg L-1) were studied. At pH 3, the removal of BPA was 95.52%, and under neutral circumstances, the BPA and TOC removals were 85.70 and 58.12%, respectively at the initial BPA concentration of 10 mg L-1. The proposed system was also applied to several water sources spiked with BPA at the concentration of 5 mg L-1 under neutral pH, which exhibited considerable removal of 99.74%, 99.72%, and 92.70% for groundwater, municipal effluent wastewater, and tap water, respectively. The proposed system was applied for 15 consecutive cycles without showing significant changes in BPA removal, indicating its excellent stability and reusability. Furthermore, based on the analysis of intermediates, a possible decomposition pathway was proposed, indicating a reduction in overall toxicity. By using the proposed heterogeneous electro-Fenton system, iron waste is avoided, and operational costs of treatment can be reduced due to the absence of iron sludge production and catalyst loss.

Degradation of Bisphenol A by Bacillus subtilis P74 Isolated from Traditional Fermented Soybean Foods

Bisphenol A (BPA), one of the most widely used plasticizers, is an endocrine-disrupting chemical that is released from plastic products. The aim of this study was to screen and characterize bacteria with excellent BPA-degrading abilities for application in foods. BPA degradation ability was confirmed in 127 of 129 bacterial strains that were isolated from fermented soybean foods. Among the strains, B. subtilis P74, which showed the highest BPA degradation performance, degraded 97.2% of 10 mg/L of BPA within 9 h. This strain not only showed a fairly stable degradation performance (min > 88.2%) over a wide range of temperatures (30-45 °C) and pH (5.0-9.0) but also exhibited a degradation of 63% against high concentrations of BPA (80 mg/L). The metabolites generated during the degradation were analyzed using high-performance liquid chromatography-mass spectrometry, and predicted degradation pathways are tentatively proposed. Finally, the application of this strain to soybean fermentation was conducted to confirm its applicability in food.

Synergistic influence of vanadium pentoxide-coupled graphitic carbon nitride composite for photocatalytic degradation of organic pollutant: Stability and involved Z-scheme mechanism

The removal of dyes from wastewater by photocatalytic technologies has received substantial attention in recent years. In the present study, novel Z-scheme V2O5/g-C3N4 photocatalytic composites were organized via simple hydrothermal processes and a sequence of several characterization aspects. The degradation results showed that the optimum Z-scheme GVO2 heterostructure composite photocatalysts (PCs) had a better efficiency (90.1%) and an apparent rate (0.0136 min-1) for the methylene blue (MB) aqueous organic dye degradation, which was about 6.18-fold higher than that of pristine GCN catalyst. Meanwhile, the GVO2 heterostructured PCs showed better recycling stability after five consecutive tests. Moreover, the free radical trapping tests established that •O2- and h+ species were the prime reactive species in the photocatalytic MB degradation process in the heterostructured PCs. The photocatalytic enhanced activity was primarily recognized as the synergistic interfacial construction of the Z-scheme heterojunctions among V2O5 and GCN, which improved the separation/transfer, lower recombination rate, extended visible-light utilization ability, and enhanced reaction rate. Therefore, the existing study affords a simple tactic for the development of a direct Z-scheme for photocatalytic heterojunction nanomaterials for potential environmental remediation applications.