The Genomic and Morphological Effects of Bisphenol A on Arabidopsis thaliana

Oxidation-reduction process of Arabidopsis thaliana roots induced by bisphenol compounds based on RNA-seq analysis

Bisphenol compounds (BPs) have various industrial uses and can enter the environment through various sources. To evaluate the ecotoxicity of BPs and identify potential gene candidates involved in the plant toxicity, Arabidopsis thaliana was exposed to bisphenol A (BPA), BPB, BPE, BPF, and BPS at 1, 3, 10 mg/L for a duration of 14 days, and their growth status were monitored. At day 14, roots and leaves were collected for internal BPs exposure concentration detection, RNA-seq (only roots), and morphological observations. As shown in the results, exposure to BPs significantly disturbed root elongation, exhibiting a trend of stimulation at low concentration and inhibition at high concentration. Additionally, BPs exhibited pronounced generation of reactive oxygen species, while none of the pollutants caused significant changes in root morphology. Internal exposure concentration analysis indicated that BPs tended to accumulate in the roots, with BPS exhibiting the highest level of accumulation. The results of RNA-seq indicated that the shared 211 differently expressed genes (DEGs) of these 5 exposure groups were enriched in defense response, generation of precursor metabolites, response to organic substance, response to oxygen-containing, response to hormone, oxidation-reduction process and so on. Regarding unique DEGs in each group, BPS was mainly associated with the redox pathway, BPB primarily influenced seed germination, and BPA, BPE and BPF were primarily involved in metabolic signaling pathways. Our results provide new insights for BPs induced adverse effects on Arabidopsis thaliana and suggest that the ecological risks associated with BPA alternatives cannot be ignored.

Futuristic advancements in phytoremediation of endocrine disruptor Bisphenol A: A step towards sustainable pollutant degradation for rehabilitated environment

Bisphenol A (BPA) accumulates in the environment at lethal concentrations because of its high production rate and utilization. BPA, originating from industrial effluent, plastic production, and consumer products, poses serious risks to both the environment and human health. The widespread aggregation of BPA leads to endocrine disruption, reactive oxygen species-mediated DNA damage, epigenetic modifications and carcinogenicity, which can disturb the normal homeostasis of the body. The living being in a population is subjected to BPA exposure via air, water and food. Globally, urinary analysis reports have shown higher BPA concentrations in all age groups, with children being particularly susceptible due to its occurrence in items such as milk bottles. The conventional methods are costly with a low removal rate. Since there is no proper eco-friendly and cost-effective degradation of BPA reported so far. The phytoremediation, green-biotechnology based method which is a cost-effective and renewable resource can be used to sequestrate BPA. Phytoremediation is observed in numerous plant species with different mechanisms to remove harmful contaminants. Plants normally undergo several improvements in genetic and molecular levels to withstand stress and lower levels of toxicants. But such natural adaptation requires more time and also higher concentration of contaminants may disrupt the normal growth, survival and yield of the plants. Therefore, natural or synthetic amendments and genetic modifications can improve the xenobiotics removal rate by the plants. Also, constructed wetlands technique utilizes the plant's phytoremediation mechanisms to remove industrial effluents and medical residues. In this review, we have discussed the limitations and futuristic advancement strategies for degrading BPA using phytoremediation-associated mechanisms.

Bisphenol-A incite dose-dependent dissimilitude in the growth pattern, physiology, oxidative status, and metabolite profile of Azolla filiculoides

Bisphenol-A (BPA) is a ubiquitous environmental pollutant affecting the growth and development of aquatic macrophytes. The present study was designed to evaluate the toxic effect of BPA on Azolla filiculoides. The plants were exposed to different concentrations of BPA and the effect was evaluated in terms of plant growth, physiological and oxidative status, responses of the antioxidative system, and changes in key metabolites. The results have shown that BPA (≥ 20 mg L^-1) incites a significant reduction in frond number, frond surface area, and growth rate of the plants along with severe frond damage, membrane peroxidation, and electrolyte leakage. Moreover, at higher concentrations, a significant reduction in the content of chlorophylls and carotenoids was observed, which was further amplified with the duration of treatments. Furthermore, excessive generation of O₂^•- and H₂O₂ invoked the antioxidative machinery under BPA exposure. However, sufficient activity of the antioxidative enzymes was observed in plants treated with ≤ 10 mg L^-1 of BPA. The untargeted metabolome profile revealed modulation of 29 metabolites including amino acids, sugar alcohols, organic acids, and phenolics in response to BPA. An increased amount of asparagine, lysine, serine, tryptophan, tyrosine, and valine after 3 days of BPA exposure indicates their role in providing better stress tolerance. Therefore, the experimental findings suggest that A. filiculoides responds differently to BPA exposure. Higher BPA concentrations (≥ 20 mg L^-1) documented a greater impact in terms of plant physiology and metabolism whereas, the effect was minimal at lower concentrations (≤ 10 mg L^-1).

Influence of bisphenol A on growth and metabolism of Vicia faba ssp. minor seedlings depending on lighting conditions

The effect of one of anthropogenic pollutants, i.e., 4,4'-isopropylidenediphenol, called 2,2-bis (4-hydroxyphenyl) propane (BPA), at 30 and 120 mg L^-1 concentrations in the darkness (DK) or dark/light (DK/LT) on growth and selected elements of metabolism of seedlings and leaf discs of Vicia faba ssp. minor was studied. Treatment with 120 mg L^-1 BPA had greater effects which were reflected by increase in the number of necrotic changes in roots and stems as well as in leaf discs and reduction of the length of roots DK and DK/LT, and volume of roots in the DK group. However, minimal and no influence on the fresh and dry weight of roots and stems in plants growing under both types of lighting conditions were observed. In both DK and DK/LT groups these effects were correlated with reduced amounts of storage and cell wall-bound sugars as well as of proteins while in the DK/LT additionally with reduced soluble sugar levels in the roots and increased amounts of hydrogen peroxide and phenols in roots and stems as well as in treatment solutions, where these compounds were released. We suggest that endogenous phenols and BPA can be metabolised in roots and stems to quinones. It seems that TB-1,4-BQ, is the one of that of the five studied quinones. We expect that the results of this paper will help to answer the following question: does the phytomeliorative and phytosanitative V. faba ssp. minor plant is enough to be resistant on negative effects, and to be useful to reduce increasing amount of BPA in the environment?

Bisphenol A-A Dangerous Pollutant Distorting the Biological Properties of Soil

Bisphenol A (BPA), with its wide array of products and applications, is currently one of the most commonly produced chemicals in the world. A narrow pool of data on BPA–microorganism–plant interaction mechanisms has stimulated the following research, the aim of which has been to determine the response of the soil microbiome and crop plants, as well as the activity of soil enzymes exposed to BPA pressure. A range of disturbances was assessed, based on the activity of seven soil enzymes, an abundance of five groups of microorganisms, and the structural diversity of the soil microbiome. The condition of the soil was verified by determining the values of the indices: colony development (CD), ecophysiological diversity (EP), the Shannon–Weaver index, and the Simpson index, tolerance of soil enzymes, microorganisms and plants (TI_BPA), biochemical soil fertility (BA₂₁), the ratio of the mass of aerial parts to the mass of plant roots (PR), and the leaf greenness index: Soil and Plant Analysis Development (SPAD). The data brought into sharp focus the adverse effects of BPA on the abundance and ecophysiological diversity of fungi. A change in the structural composition of bacteria was noted. Bisphenol A had a more beneficial effect on the Proteobacteria than on bacteria from the phyla Actinobacteria or Bacteroidetes. The microbiome of the soil exposed to BPA was numerously represented by bacteria from the genus Sphingomonas. In this object pool, the highest fungal OTU richness was achieved by the genus Penicillium, a representative of the phylum Ascomycota. A dose of 1000 mg BPA kg⁻¹ d.m. of soil depressed the activity of dehydrogenases, urease, acid phosphatase and β-glucosidase, while increasing that of alkaline phosphatase and arylsulfatase. Spring oilseed rape and maize responded significantly negatively to the soil contamination with BPA.

Hazards of bisphenol A (BPA) exposure: A systematic review of plant toxicology studies

The widespread use of bisphenol A (BPA) has led to its ubiquity in the natural environment. Thus, BPA is considered as a contaminant of emerging concern. Due to its widespread use, BPA has been detected in a range of soils and surface waters. This is of concern because BPA has been shown to elicit slight to moderate toxicity to plants. Based on current research and our own work, this paper reviews the toxic effects of BPA on plant growth and development, including effects at the macroscopic (e.g. seed germination, root, stem, and leaf growth) and microscopic (photosynthesis, uptake of mineral nutrient, hormone secretion, antioxidant systems, and reproductive genetic behavior) levels. Furthermore, this paper will discuss effects of BPA exposure on metabolic reactions in exposed plant species, and explore the use of high-efficiency plants in BPA pollution control (e.g. phytoremediation). Finally, this paper proposes some ideas for the future of BPA phytotoxicity research.

The mechanism of root growth inhibition by the endocrine disruptor bisphenol A (BPA)

Bisphenol A (BPA) is a harmful environmental contaminant acting as an endocrine disruptor in animals, but it also affects growth and development in plants. Here, we have elucidated the functional mechanism of root growth inhibition by BPA in Arabidopsis thaliana using mutants, reporter lines and a pharmacological approach. In response to 10 ppm BPA, fresh weight and main root length were reduced, while auxin levels increased. BPA inhibited root growth by reducing root cell length in the elongation zone by suppressing expansin expression and by decreasing the length of the meristem zone by repressing cell division. The inhibition of cell elongation and cell division was attributed to the enhanced accumulation/redistribution of auxin in the elongation zone and meristem zone in response to BPA. Correspondingly, the expressions of most auxin biosynthesis and transporter genes were enhanced in roots by BPA. Taken together, it is assumed that the endocrine disruptor BPA inhibits primary root growth by inhibiting cell elongation and division through auxin accumulation/redistribution in Arabidopsis. This study will contribute to understanding how BPA affects growth and development in plants.

Hydrogen Peroxide Production by the Spot-Like Mode Action of Bisphenol A

Bisphenol A (BPA), an intermediate chemical used for synthesizing polycarbonate plastics, has now become a wide spread organic pollutant. It percolates from a variety of sources, and plants are among the first organisms to encounter, absorb, and metabolize it, while its toxic effects are not yet fully known. Therefore, we experimentally studied the effects of aqueous BPA solutions (50 and 100 mg L^-1, for 6, 12, and 24 h) on photosystem II (PSII) functionality and evaluated the role of reactive oxygen species (ROS) on detached leaves of the model plant Arabidopsis thaliana. Chlorophyll fluorescence imaging analysis revealed a spatiotemporal heterogeneity in the quantum yields of light energy partitioning at PSII in Arabidopsis leaves exposed to BPA. Under low light PSII function was negatively influenced only at the spot-affected BPA zone in a dose- and time-dependent manner, while at the whole leaf only the maximum photochemical efficiency (Fv/Fm) was negatively affected. However, under high light all PSII photosynthetic parameters measured were negatively affected by BPA application, in a time-dependent manner. The affected leaf areas by the spot-like mode of BPA action showed reduced chlorophyll autofluorescence and increased accumulation of hydrogen peroxide (H₂O₂). When H₂O₂ was scavenged via N-acetylcysteine under BPA exposure, PSII functionality was suspended, while H₂O₂ scavenging under non-stress had more detrimental effects on PSII function than BPA alone. It can be concluded that the necrotic death-like spots under BPA exposure could be due to ROS accumulation, but also H₂O₂ generation seems to play a role in the leaf response against BPA-related stress conditions.

The effects of Bisphenol A on the seagrass Cymodocea nodosa: Leaf elongation impairment and cytoskeleton disturbance

Bisphenol A (BPA) is an emerging pollutant of environmental concern, classified as "moderately toxic" and "toxic", causing adverse effects on aquatic biota. Although information about BPA toxicity on aquatic fauna is available, the data about BPA effects on aquatic flora remain scarce, missing for marine macrophytes. The effects of environmentally relevant BPA concentrations (ranging from 0.03 to 3 μg L^-1) on juvenile leaf elongation and the cytoskeleton (microtubules, MTs and actin filaments, AFs) were studied in the seagrass Cymodocea nodosa for 1-10 days. The suitability of cytoskeleton disturbance and leaf elongation impairment as "biomarkers" for BPA stress were tested. The highest BPA concentrations (0.3, 0.5, 1 and 3 μg L^-1) affected significantly leaf elongation from the onset of the experiment, while defects of the cytoskeleton were observed even at lower concentrations. In particular, MTs were initially disrupted (i.e. "lowest observed effect concentrations", LOECs) at 0.1 μg L^-1, while AFs were damaged even at 0.03 μg L^-1. AFs appeared thus to be more sensitive to lower BPA concentrations, while there was a correlation between leaf elongation impairment and MT defects. Thus, AF damages, MT disruption and leaf elongation impairment in C. nodosa, in this particular order, appear to be sensitive "biomarkers" of BPA stress, at the above environmentally relevant BPA concentrations.

Disruption of actin filaments in Zea mays by bisphenol A depends on their crosstalk with microtubules

Bisphenol A (BPA) is a widespread environmental pollutant, reportedly harmful to living organisms. In plant cells, BPA was shown to disrupt microtubule (MT) arrays and perturb mitosis, but its effects on filamentous actin (F-actin) have not been explored. Here we studied the effects of BPA on actin filaments (AFs) in meristematic root tip and leaf cells of Zea mays, by fluorescent labeling and confocal microscopy. Considering the typical dynamic interaction between MTs and AFs, the effects on these two essential components of the plant cytoskeleton were correlated. It was found that BPA disorganized rapidly AFs in a concentration- and time-dependent manner. The fine filaments were first to be affected, followed by the subcortical bundles, resulting in rod- and ring-like conformations. The observed differences in sensitivity between protodermal and cortex cells were attributed to the deeper location of the latter. Depolymerization or stabilization of MTs by relevant drugs (oryzalin, taxol) revealed that AF susceptibility to BPA depends on MT integrity. Developing leaves required harder and longer treatment to be affected by BPA. Ontogenesis of stomatal complexes was highly disturbed, arrangement of AFs and MT arrays was disordered and accuracy of cell division sequence was deranged or completely arrested. The effect of BPA confirmed that subsidiary cell mother cell polarization is not mediated by F-actin patch neither of preprophase band organization. On the overall, it is concluded that AFs in plant cells constitute a subcellular target of BPA and their disruption depends on their crosstalk with MTs.