The biosurfactant-producing bacterial isolate was isolated from an oil-contaminated water sample. This study aimed to determine the production of biosurfactant and its effect on the plant growth via ...the biosorption of some heavy metals. The isolate was identified by 16S rRNA gene sequence analysis as Bacillus megaterium ATTC 14581. The surface activity of the produced biosurfactant was determined. The biosurfactant was recovered from the cell-free culture of a bacterial strain at 1.5 g/L. The extracted biosurfactant shows potential stability towards some factors, like temperature and salinity. The FTIR analysis confirmed the production of surfactin biosurfactant. The impact of B. megaterium biosurfactant on Pb and Ar significantly increases morphological features, proline, and antioxidant enzymes, while a significant decrease in lipid peroxidation, H2O2, and O2.
Pine wilt disease caused by Bursaphelenchus xylophilus is an extremely serious issue worldwide. Trichoderma asperellum is used as a biocontrol agent due to its efficient inhibition of various ...pathogens. Three solvents, methanol, petroleum ether, and acetone, were used for extracting the fermentation broth of T. asperellum. All three extracts displayed a significant difference in nematocidal efficacy of more than 70% at 72 hours. Water-soluble natural products or polyphenolic compounds exhibited the greatest nematocidal ability after 24 hours of treatment with methanol. However, lipophilic substances exhibit long-lasting nematocidal ability. During this process, the antioxidant enzyme activities of T. asperellum significantly increased, including those of catalase, superoxide dismutase, and peroxidase. The interaction between T. asperellum and B. xylophilus induces the synthesis of glycoside hydrolase family 18 (chitinases) and peptidase S8, potential subtilisin, which dissolve the body wall of the nematodes. Fatty acid metabolism was significantly increased, and a defensive response against substances secreted by the nematode was produced. Antioxidant reaction mechanisms and detoxification metabolism were enriched and included a large number of upregulated DEGs, including GST, CYP450, LysM, and RTA1. The dual and toxic mechanisms exhibited by T. asperellum during its response to B. xylophilus involve multiple pathways and genes that are collectively regulated. This is the first study to investigate the effects of T. asperellum on B. xylophilus. This study provides a theoretical basis for the potential use of T. asperellum as a biocontrol agent against B. xylophilus.
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•All three extracts had a significant difference in nematicidal efficacy of more than 70%.•T. asperellum increased antioxidant enzyme activities including CAT, SOD, and POD.•Detoxification metabolism was enriched, including GST, CYP450, LysM, and RTA1.•Chitinases, and subtilisin dissolved the body wall of the nematodes.•In the network, three transporter and four oxidases in highly connected genes.
Microplastics, recognized as some of the most pervasive and enduring pollutants, have emerged as a potential threat to environmental eco-health. While much is known about the effects of microplastics ...on soil microorganisms, our understanding of how they interact with terrestrial organisms and the underlying mechanisms remains limited. In this study, the effects of polyethylene microplastics at a concentration of 0.5 % (w/w) on the antioxidant enzymes, gut microbiota of Eisenia fetida and the soil microbiota on days 1, 3, 7, 15, and 30 were investigated. The results indicated that exposure to microplastics slightly increased the activities of superoxide dismutase (1.22-fold on day 3, 1.12-fold on day 7) and catalase (1.10-fold on day 3, 1.09-fold on day 7) in E. fetida, while exposure markedly decreased peroxidase activity (1.33- to 1.79-fold) throughout the whole period. Both the soil microbiota and the gut microbiota of E. fetida in terms of diversity and composition were significantly affected by the microplastic amendment, and their structure tended to be similar throughout the exposure time. The family Nocardiaceae was significantly enriched in both the soil and E. fetida gut biota with microplastic exposure. Our results demonstrated that the antioxidant enzyme response of E. fetida was closely related to both the microbiota, although this relationship with the gut microbiota may have been weakened by microplastic exposure. Overall, this study furnishes new perspectives on the ecotoxicity of microplastics, revealing significant implications for the vitality of soil-dwelling organisms and the overarching health of terrestrial ecosystems.
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•LDPE microplastics altered the activity of antioxidant enzymes in Eisenia fetida.•LDPE microplastics altered the structure and composition of soil and gut microbiota.•Nocardia and Rhodococcus were enriched in both the soil and Eisenia fetida under exposure.•Correlation between antioxidase system and gut microbiota was weakened under exposure.
The application of silicon (Si) under heavy metal stress is well known, but the use of Si nanoparticles (NPs) under metal stress in not well documented. Thus, the experiments were performed to ...investigate the impacts of soil and foliar applied Si NPs on wheat (Triticum aestivum L.) growth and cadmium (Cd) accumulation in grains under Cd toxicity. The plants were grown under natural environmental conditions and were harvested after physiological maturity (124 days after sowing). The results demonstrated that Si NPs significantly improved, relative to the control, the dry biomass of shoots, roots, spikes and grains by 24–69%, 14–59%, 34–87%, and 31–96% in foliar spray and by 10–51%, 11–49%, 25–69%, and 27–74% in soil applied Si NPs, respectively. The Si NPs enhanced the leaf gas exchange attributes and chlorophyll a and b concentrations, whereas diminished the oxidative stress in leaves which was indicated by the reduced electrolyte leakage and enhancement in superoxide dismutase and peroxidase activities in leaf under Si NPs treatments over the control. When compared with the control, the foliar spray of Si NPs reduced the Cd contents in shoots, roots, and grains by 16–58%, 19–64%, and 20–82%, respectively, whereas soil applied Si NPs reduced the Cd concentrations in shoots, roots, and grains by 11–53%, 10–59%, and 22–83%, respectively. In comparison with the control, Si concentrations significantly (p ≤ 0.05) increased in the shoots and roots in both foliar and soil supplementation of Si NPs. Our results suggested that Si NPs could improve the yield of wheat and more importantly, reduce the Cd concentrations in the grains. Thus, the use of Si NPs might be a feasible approach in controlling Cd entry into the human body via crops.
•Silicon nanoparticles (Si NPs) increased the growth of wheat under cadmium (Cd) stress.•Si NPs increased the photosynthesis in Cd-stressed wheat leaves.•Si NPs decreased the oxidative stress in leaves of wheat.•Si NPs decreased the Cd concentrations and increased the Si concentrations in wheat.
The activities of antioxidant factors superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) were measured in the livers of Takifugu rubripes cultured at 16 °C, 20 °C, 24 °C, ...28 °C, and 32 °C. Additive main effects and multiplicative interaction (AMMI) and genotype main effects and genotype × environment interaction (GGE) Biplot analyses were used to analyze the effects of genotype × temperature interactions on the antioxidant activities. The results of AMMI analysis revealed that antioxidant activities were significantly affected by genotype (93.532%), temperature (2.978%), and genotype × temperature (2.026%) interactions. GGE Biplot analysis revealed differences in the ranking of the three antioxidant activities at the five culture temperatures: the strongest ability to distinguish the three antioxidant factors was detected at 16 °C; the five test temperatures were divided into two regions, 16–20 °C and 24–32 °C; the activity of SOD was highest at 16–20 °C and GPX activity was highest at 24–32 °C; SOD exhibited the best activity and stability of the three antioxidants at the five temperatures tested.
•Genotype was the major contributor to the total variation in antioxidant factor activity .•The strongest ability to distinguish the three antioxidant factors was detected at 16 °C.•The five test temperatures were divided into two regions, 16–20ºC region and 24–32ºC region.•SOD exhibited the best activity and stability of the three antioxidants at the five temperatures tested.
Heavy metals (HMs) are among the most dangerous environmental variables for a variety of life forms, including crops. Accumulation of HMs in consumables and their subsequent transmission to the food ...web are serious concerns for scientific communities and policy makers. The function of essential plant cellular macromolecules is substantially hampered by HMs, which eventually have a detrimental effect on agricultural yield. Among these HMs, three were considered, i.e., arsenic, cadmium, and chromium, in this review, from agro-ecosystem perspective. Compared with conventional plant growth regulators, the use of nanoparticles (NPs) is a relatively recent, successful, and promising method among the many methods employed to address or alleviate the toxicity of HMs. The ability of NPs to reduce HM mobility in soil, reduce HM availability, enhance the ability of the apoplastic barrier to prevent HM translocation inside the plant, strengthen the plant's antioxidant system by significantly enhancing the activities of many enzymatic and nonenzymatic antioxidants, and increase the generation of specialized metabolites together support the effectiveness of NPs as stress relievers. In this review article, to assess the efficacy of various NP types in ameliorating HM toxicity in plants, we adopted a ‘fusion approach’, in which a machine learning-based analysis was used to systematically highlight current research trends based on which an extensive literature survey is planned. A holistic assessment of HMs and NMs was subsequently carried out to highlight the future course of action(s).
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•Current status, potentials and issue of nanotechnology in minimizing heavy metal stress, assessed.•Integration of bibliometric analysis with in-depth assessment used.•Nanomaterials are found to be effective in minimizing heavy metal accumulation in crops.•Role of surface modifications of nanomaterials, agro-environmental issues discussed.•Potentials of different nanomaterials along with research gap areas are critically assessed.
Tetrabromobisphenol A (TBBPA) and its derivatives are widely used as brominated flame retardants. Because of their high production and wide environment distribution, TBBPA derivatives have increased ...considerable concern. Previous studies have primarily focused on TBBPA, with limited information available on its derivative. In this study, we investigated the uptake, biotransformation and physiological response of two derivatives, Tetrabromobisphenol A bis(allyl ether) (TBBPA BAE) and Tetrabromobisphenol A bis(2,3-dibromopropylether) (TBBPA BDBPE), in Helianthus annus (H. annus) through a short-term hydroponic assay. The results revealed that H. annus could absorb TBBPA BAE and TBBPA BDBPE from solution, with removal efficiencies of 98.33 ± 0.5% and 98.49 ± 1.56% after 10 days, respectively, which followed first-order kinetics. TBBPA BAE was absorbed, translocated and accumulated while TBBPA BDBPE couldn't be translocated upward due to its high hydrophobicity and low solubility. The concentrations of TBBPA derivatives in plants peaked within 72 h, and then decreased. We identified twelve metabolites resulting from ether bond breakage, debromination, and hydroxylation in H. annus. The high-level TBBPA BAE suppressed the growth and increased malondialdehyde (MDA) content of H. annus, while TBBPA BDBPE didn't pose a negative effect on H. annus. TBBPA BAE and TBBPA BDBPE increased the activity of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), with higher levels of these enzymes activity found in high concentration treatments. Contrastingly, TBBPA BAE exhibited higher toxicity than TBBPA BDBPE, as indicated by greater antioxidant enzyme activity. The findings of this study develop better understanding of biotransformation mechanisms of TBBPA derivatives in plants, contributing to the assessment of the environmental and human health impacts of these contaminants.
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•H. annus could uptake TBBPA derivatives, but translocation of TBBPA BDBPE was limited.•TBBPA derivatives' ether breakage, debromination and hydroxylation in H. annus.•High-level of TBBPA BAE inhibited the growth and development of H. annus.•TBBPA derivatives induced SOD, POD and CAT activities in H. annus.•TBBPA BAE has higher toxicity than TBBPA BDBPE.
The different wheat varieties have different tolerance to cadmium stress, while the mechanisms underlying the Cd tolerance are still poorly understood. A pot experiment was conducted to study the ...changes of antioxidant enzyme activities and endogenous hormones in wheat (Triticum aestivum) genotypes differing in cadmium (Cd) accumulation (low = Pingan 8 and high = Bainong 160) in different growth stages under Cd stress. The Cd treatment (3 mg/kg) increased the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) and concentrations of malondialdehyde (MDA) and abscisic acid (ABA); in contrast, it reduced the net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), intercellular carbon dioxide concentration (Ci) and the concentrations of gibberellin (GA3), auxin (IAA) and zeatin nucleoside (ZR) in wheat leaves compared to the CK (without Cd). The antioxidant enzyme activities were higher in Bainong 160 than Pingan 8 under Cd stress. In addition, the changes in endogenous hormone concentration were smaller in Bainong 160 than Pingan 8 leaves. The correlation coefficients of Bainong 160 and Pingan 8 were 0.87 and 0.66, respectively. Our results suggest that high Cd accumulation (greater Cd tolerance) in Bainong 160 is associated with higher photosynthetic parameters, higher activities of antioxidant enzyme and higher concentration of hormones than Pingan 8.
•Study of two varieties in response to Cd stress of by grey correlation analysis.•The Cd tolerance of wheat is related to antioxidant enzyme and plant hormone.•The Cd accumulation and tolerance of Bainong 160 are higher than those of Pingan 8.
•MgONPs were synthesized through green approach using trichoderma fungus.•Myco-synthesized NPs exhibited strong nematicidal activity.•Soil application of NPs improved plant growth under nematode ...infection.•Soil application of NPs reduced nematode population and development.
Meloidogyne incognita is believed to be the most devastating pest causing severe damage to crops, and hence, innovative and effective means of controlling the nematode is the need of the day. The focus of the current study is to devise an effective and innovative myco-fabrication of MgO nanoparticles (NPs) along with melatonin for efficient management of M. incognita infecting tomatoes. Fungal extracts were used to synthesize the myco-fabricated NPs through a green synthesis pathway and were verified using different spectroscopic means. The nanoparticles exhibited appreciable nematicidal potential, such as drastic egg hatch inhibition and juvenile mortality under in vitro assays. Evaluation of NPs and melatonin in planta, alone or combined form, was investigated on tomato plants already inoculated with M. incognita. The alterations in the nematode population on roots of plants as well as in soil, growth parameters, and biochemical attributes of plants were recorded. A significant reduction in nematode population was revealed on the application of melatonin and myco-fabricated nanoparticles, hence exhibiting an improvement in the plant's biochemical (glutathione, phenolic, flavonoid, and antioxidant enzymes) and growth parameters. A synergistic impact was shown on the combined application of the treatments. Furthermore, an enhancement in the expression as well as activities of antioxidant enzymes was also observed. Increased resistance of plants against nematodes resulted in connection with the improved antioxidant status of plants due to this combined treatment. The significantly improved growth of plants under M. incognita stress conditions reveals the potential of the proposed treatments having synergistic interaction to manage phyto-parasitic nematodes effectively. This presents innovative means of agricultural biotechnologies that have the potential to contribute to the efficient management of nematodes infecting plants.
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