Studying the combined phytotoxicity of PFOA with Fe2O3 or MnO2 nanoparticles (NPs) is paramount for addressing the remediation of PFOA-contaminated agricultural soils and assessing the efficacy of nanoparticle-assisted phytoremediation strategies. By exposing radish plants to PFOA with/without Fe2O3 or MnO2 NPs for 60 days, this study delved into radish biomass, PFOA accumulation, chlorophyll pigments, antioxidant defenses, and nutrient contents. Key findings showed that PFOA at environmentally relevant levels (20 mu g/kg) were highly toxic to radish plants. PFOA accumulated significantly in radish organs, especially in the shoots. Additionally, PFOA exposure had a detrimental impact on radish growth. However, the application of Fe2O3 and MnO2 NPs facilitated the translocation of PFOA up to shoots, thereby reducing its accumulation in the edible roots. Additionally, they could significantly increase radish biomass and mitigate the damages caused by PFOA, evidenced by lower MDA contents and higher amino acid contents. This study highlights the potential of nanoparticle-enhanced phytoremediation as an effective approach for PFOA-polluted agricultural soils. By promoting the translocation of harmful pollutants away from edible plant parts and enhancing plant growth and resilience, Fe2O3 and MnO2 NPs offer a promising avenue for sustainable soil remediation strategies.

In this study, novel block copolymers consisting of poly(ethylene succinate) (PES) and poly(amino acid)s were synthesized, and their thermal and mechanical properties and biodegradability characteristics were investigated. Various types of poly(amino acid) units were successfully introduced using N-phenyloxycarbonyl amino acids (NPCs). The reactions between the terminally aminated PES and the NPCs were conducted by heating in N,N-dimethylacetamide at 65 degrees C. Structural analyses of the obtained polymers confirmed that the reaction with the NPCs proceeded from both ends of the terminally aminated PES. The results of material property measurements demonstrated that the melting point of the block copolymer containing poly(alanine) units increased beyond 200 degrees C while that of the original PES was similar to 100 degrees C. Additionally, its strain at break increased similar to 80-fold compared to that of PES with a similar molecular weight. The results of biodegradability tests using a soil suspension as an inoculum indicated that some of the block copolymers underwent biodegradation, and a correlation was observed between the biodegradability and the type and feed amount of NPC. Therefore, it was proposed that the degree, rate, and onset time of biodegradation could be controlled by altering the type and amount of incorporated poly(amino acid) units. This research may contribute to the optimal and facile synthesis of polyester-b-poly(amino acid) copolymers and to the expansion of the range of available biodegradable materials.

Mycorrhizal associations play a crucial role in afforestation efforts, as they enhance the acquisition of nutrients and water, thereby supporting seedling establishment. However, the influence of nitrogen (N) forms in the soil, particularly the organic N, on the formation of mycorrhizal associations and their subsequent effects on seedling morpho-physiology remains poorly understood. In this study, we examine the mycorrhizal colonization, along with morpho-physiological and functional traits, in Pinus cooperi seedlings following fertilization with organic N in controlled nursery conditions. A factorial experiment was performed with Pinus cooperi C. E. Blanco seedlings using two N sources: organic N (amino acids) and inorganic N (NH4NO3) and two N doses: low and high (60 vs 200 mg N seedling-1). Seedlings were inoculated with a mixture of native fungi, but the phylogenetic analysis showed that Suillus placidus (Bonord.) Singer was the only species colonizing roots. Organic N promoted similar morphology and nutritional status as inorganic N, though at a low N rate, it improved root growth and mycorrhizal colonization. High N fertilization improved seedling growth and nutritional status but reduced mycorrhizal colonization. Mycorrhizal colonization improved needle P concentration, delayed plant desiccation, and reduced root cellular damage when seedlings were subjected to desiccation, though it decreased plant growth and needle N concentration. We conclude that organic N fertilization improves mycorrhization of P. cooperi with S. placidus, but the fertilization dose should be adjusted to meet species-specific requirements in order to optimize plant quality and promote afforestation success.

This study investigates the role of 24-epibrassinolide (BR, 10- 2 mu M) in mitigating arsenic (As)-induced stress in maize (Zea mays L. cv. 704). Seedlings were exposed to As at concentrations of 0, 5, 10, 25, 50, 100, and 250 mu M, with or without BR application. Arsenic exposure increased oxidative damage markers such as MDA and H2O2 while BR treatment significantly enhanced antioxidant enzymes activities including ascorbate peroxidase (APX), catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), glutathione reductase (GR) and glutathione Stransferase (GST), reducing reactive oxygen species (ROS) levels, and minimizing oxidative damage. Additionally, BR significantly increased proline, phenolic compounds, flavonoids, and soluble sugars, contributing to osmoprotection and stress tolerance, as well as enhancing FRAP and DPPH antioxidant activities. Furthermore, BR increased amino acids (AAs) such as proline (Pro), cysteine (Cys), glutamine (Gln), and glutamate (Glu). Gene expression analysis revealed significant upregulation of detoxification-related genes including cytochrome P450 monooxygenases (CYPs), GT1, GST27 and multidrug resistance-associated proteins (MRPs) under BR treatment. These findings suggest that BR enhances maize tolerance to As toxicity by activating detoxification pathways, improving antioxidant defense, and stabilizing metabolic processes. The results underscore the potential application of BR in sustainable agriculture to improve crop resilience in As-contaminated soils.

Biosurfactants are one of the recently investigated biomolecules that have enormous applications in many fields including agriculture. As there is a need to develop less toxic, and environmentally friendly surfactants, therefore, amino acid-based biosurfactants that are produced from renewable raw materials are of great demand nowadays and can be used as an alternative to conventional chemical surfactants. The negative effects of chemical surfactants present in agrochemicals and modern detergents can damage human health and the environment, thus there is a crucial requirement to explore innovative, well planned, as well as cost-effective natural products for the welfare of humanity. Biodegradable surfactants created through green chemistry, specifically amino acid-based surfactants, are a favourable alternative to avoid these risks. Since amino acids (AAs) are inexhaustible compounds, therefore biosurfactants based on AAs have abundant potential as eco-friendly and environmentally friendly substances. Their higher biodegradation ability, low or even no toxicity, temperature stability, and tolerance to pH fluctuations make these biosurfactants preferable over chemical surfactants. In modern agriculture, most chemical pesticides and fertilizers used are frequently associated with numerous environmental issues. Hence, the development of green molecules as biosurfactants has a promising role in this regard to ensure agricultural sustainability. Biosurfactants can be harnessed for plant pathogen management, plant growth elevation, improving the quality of agricultural soil by soil remediation, degradation of complex hydrocarbons, increasing bioavailability of nutrients for advantageous plant-microbe interactions, and improving plant immunity, hence, they can supersede the grim synthetic surfactants which are presently being used.

AimThe unregulated use of rare earth elements, such as Europium (Eu), may result in their build-up in soils. Here, we investigated how Eu affects wheat growth, photosynthesis, and redox homeostasis and how Arbuscular mycorrhizal fungi (AMF) may influence these processes.MethodsThe wheat plants were grown in soil with 1.09 mmol Eu3+/kg and/or AMF inoculation. The study is mainly based on a comprehensive examination of the detailed biochemical and metabolic mechanisms underlying the Eu stress mitigating impact of Eu by AMF in wheat plants.ResultsSoil contamination with Eu significantly induced a reduction in biomass accumulation and photosynthesis-related parameters, including photosynthetic rate (61%) and chlorophyll content (24.6%). On the other hand, AMF could counteract Eu's induced growth and photosynthesis inhibition. Under Eu stress, AMF colonization significantly increased fresh and dry weights by 43% and 23.5%, respectively, compared to Eu treatment. AMF colonization also induced minerals (e.g., Ca, K, Zn, and N) uptake under control and Eu stress conditions. By bolstering the antioxidant defense mechanisms, such as ROS-scavenging metabolites (flavonoids and polyphenols), AMF mitigated Eu-induced oxidative damage. In terms of the primary metabolites, organic acids, essential amino acids, and unsaturated fatty acids were increased by AMF colonization, particularly under Eu stress conditions.ConclusionApplying AMF is a workable approach for reducing Eu toxicity in wheat plants.

Biomimetic mineralized mortar (BMM) represents a novel green cementitious material, increasingly recognized for its environmental sustainability. In this study, four typical amino acids including acidic amino acids (aspartic acid, glutamic acid), neutral amino acid (threonine), and basic amino acid (arginine), are employed as crystal modifiers to develop the high-strength BMM (HBMM) based on the biomimetic chemically induced calcium carbonate precipitation (BCICP) method. The mechanical properties and failure morphology of HBMM were evaluated through unconfined compressive strength (UCS) test. The microstructure characteristics of HBMM were investigated using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and contact angle test. The results show that amino acid-modified calcium carbonate precipitation can effectively cement loose sand particles and significantly improve the strength of the HBMM. The failure modes of HBMM observed include local failure, vertical splitting failure, shear failure, and splitting- shear mixed failure. Notably, aspartic acid and glutamic acid can induce the formation of vaterite-phase calcium carbonate crystals, while threonine and arginine facilitate the formation of aragonite-phase calcium carbonate crystals. The hydrogen bonding between modified calcium carbonate crystals and silanol groups on the silica surface ensures a tight adhesion of the precipitate to sand surfaces, filling gaps and cementing particles. This study elucidates that using amino acids as modifiers in the BCICP method can significantly enhance the strength of HBMM and influence its microstructure, offering valuable insights for its potential practical applications.

Zinc (Zn) deficiency and salt stress are well-known soil problems and often happen parallelly in cultivated soils. In this study, Zn-amino acid complexes (Zn-AAc) were used as a source of Zn to determine their effects on salt-induced damage in wheat plants. The bread wheat (Triticum aestivum L. cvs. Kavir) was supplied with Zn-glycine (Zn-Gly), Zn-alanine (Zn-Ala), and ZnSO4 as Zn sources at three salinity levels (EC 2, 4 and 6 dS m(-)). Salinity caused a significant decrease in shoot dry matter and grain yield of wheat, but this negative effect was significantly improved by the application of Zn-AAc. Salt stress decreased shoot and grain Zn concentration, but this reduction was lower in plants supplied by Zn-AAc. Calcium (Ca) and potassium (K) concentrations were increased in a shoot by salinity stress while decreased in grain. Sodium (Na) concentration decreased in shoot and grain by using Zn-AAc. At all of the salinity levels, wheat supplied with Zn-AAc had lower lipid peroxidation compared to those grown under the ZnSO4 source. Application of Zn-AAc increased the activities of catalase (CAT) and superoxide dismutase (SOD) in the roots of wheat plants in saline conditions. Based on the results, the adverse effects of salinity stress on wheat plants can moderately improve with Zn-AAc application.

Soil salinization has damaged the soil biological environment and chemical structure, resulting in a decline in soil quality and crop yields, which has caused harm to the ecological environment and human health, and severely hindered the development of the economy. In this experiment, using the 'Ningdan 33' maize seeds as materials, the maize was treated with histidine and salt stress (100 mM NaCl), and photosynthesis, photosynthetic enzyme activity, relative expression of photosynthetic genes of maize were measured. The anatomical structure of the leaves was also observed. The study explored the impact of exogenous histidine treatment on the photosynthesis of maize under salt stress. When the concentration of histidine sprayed on the leaves was 0.5 mM, it had the best effect on promoting photosynthesis in maize under salt stress. 0.5 mM histidine significantly improved the photosynthetic performance ( P N , g s , E , Chl a /Chl b ) of maize under salt stress, significantly improved photosynthesis efficiency (F v /F m , Delta F/F' m , q P were significantly increased. NPQ was significantly decreased), significantly increased the activity of photosynthetic enzymes (PEPC, NADP-ME, PPDK, Rubisco) and the relative expression of photosynthetic genes ( ZmPEPC , ZmNADP-ME , ZmPPDK , ZmRCA ), increased the length of the vascular bundle in the cross- of the leaf, played a certain protective role on the vascular bundle, and improved the efficiency of material transportation under salt stress. Based on the above analysis, 0.5 mM histidine can significantly improve the tolerance of maize under salt stress, which has great application value for planting maize in saline environments.

The intake of methylmercury (MeHg)-contaminated rice poses immense health risks to rice consumers. However, the mechanisms of MeHg accumulation in rice plants are not entirely understood. The knowledge that the MeHg-Cysteine complex was dominant in polished rice proposed a hypothesis of co-transportation of MeHg and cysteine inside rice plants. This study was therefore designed to explore the MeHg accumulation processes in rice plants by investigating biogeochemical associations between MeHg and amino acids. Rice plants and underlying soils were collected from different Hg-contaminated sites in the Wanshan Hg mining area. The concentrations of both MeHg and cysteine in polished rice were higher than those in other rice tissues. A significant positive correlation between MeHg and cysteine in rice plants was found, especially in polished rice, indicating a close geochemical association between cysteine and MeHg. The translocation factor (TF) of cysteine showed behavior similar to that of the TF of MeHg, demonstrating that these two chemical species might share a similar transportation mechanism in rice plants. The accumulation of MeHg in rice plants may vary due to differences in the molar ratios of MeHg to cysteine and the presence of specific amino acid transporters. Our results suggest that cysteine plays a vital role in MeHg accumulation and transportation inside rice plants.