Pulsed high power microwave seeds priming modulates germination, growth, redox homeostasis, and hormonal shifts in barley for improved seedling growth: Unleashing the molecular dynamics.

Increasing the seed germination potential and seedling growth rates play a pivotal role in increasing overall crop productivity. Seed germination and early vegetative (seedling) growth are critical developmental stages in plants. High-power microwave (HPM) technology has facilitated both the emergence of novel applications and improvements to existing in agriculture. The implications of pulsed HPM on agriculture remain unexplored. In this study, we have investigated the effects of pulsed HPM exposure on barley germination and seedling growth, elucidating the plausible underlying mechanisms. Barley seeds underwent direct HPM irradiation, with 60 pulses by 2.04 mJ/pulse, across three distinct irradiation settings: dry, submerged in deionized (DI) water, and submerged in DI water one day before exposure. Seed germination significantly increased in all HPM-treated groups, where the HPM-dry group exhibited a notable increase, with a 2.48-fold rise at day 2 and a 1.9-fold increment at day 3. Similarly, all HPM-treated groups displayed significant enhancements in water uptake, and seedling growth (weight and length), as well as elevated levels of chlorophyll, carotenoids, and total soluble protein content. The obtained results indicate that when comparing three irradiation setting, HPM-dry showed the most promising effects. Condition HPM seed treatment increases the level of reactive species within the barley seedlings, thereby modulating plant biochemistry, physiology, and different cellular signaling cascades via induced enzymatic activities. Notably, the markers associated with plant growth are upregulated and growth inhibitory markers are downregulated post-HPM exposure. Under optimal HPM-dry treatment, auxin (IAA) levels increased threefold, while ABA levels decreased by up to 65 %. These molecular findings illuminate the intricate regulatory mechanisms governing phenotypic changes in barley seedlings subjected to HPM treatment. The results of this study might play a key role to understand molecular mechanisms after pulsed-HPM irradiation of seeds, contributing significantly to address the global need of sustainable crop yield.

Elevating sensing capability via dual-atom catalysts boosted luminol cathodic electrochemiluminescence.

BACKGROUND: The advancement of highly sensitive electrochemiluminescence (ECL) biosensors has garnered escalating interest over time. Owing to the distinctive physicochemical attributes, the signal amplification strategy facilitated by functional nanomaterials has achieved notable milestones. Single-atom catalysts (SACs), featuring atomically dispersed metal active sites, have garnered significant attention. SACs offer unprecedented control over active sites and surface structures at the atomic level. However, to fully harness their potential, ongoing efforts focus on strategies to enhance the catalytic performance of SACs, profoundly influencing both the sensitivity and selectivity of SACs-based sensing platforms. RESULTS: In this study, we focused on the synthesis and application of Fe-Co-PNC dual-atom catalysts (DACs) with the incorporation of phosphorus, aiming to enhance catalytic efficiency, particularly in the context of the oxygen reduction reaction (ORR) correlated cathodic luminol ECL. The synergistic effects arising from the combination of Fe and Co in DACs were explored by ECL emission. Comparative studies with Fe-PNC SACs highlighted the superior catalytic performance of Fe-Co-PNC DACs. The ECL sensing platform exhibited excellent sensitivity, which provided a fast detection of Trolox with a wide linear range (0.1 µM-1.0 mM) and a low detection limit (LOD) of 0.03 µM. The platform demonstrated remarkable reproducibility and long-term stability, showcasing its potential for practical biosensing applications. SIGNIFICANCE: This study introduced the novel concept of Fe-Co-PNC DACs. The demonstrated synergistic effects and enhanced catalytic efficiency of DACs offer new avenues for the rational design of advanced catalysts. The successful application in the sensitive detection of Trolox emphasizes their potential significance in biosensing. It not only expands our understanding of SACs but also opens doors for the development of efficient and stable catalysts with broader applications.

Nonmetal catalyst boosting amplification of both colorimetric and electrochemical signal for multi-mode nitrite sensing.

Recently, nanozymes as an outstanding alternative to natural enzymes has attracted wide attention because of its high stability performance. In this study, PNC nonmetal nanozymes with high oxidase-like activity was synthesized can specifically catalyze colorless 3,3,5,5-tetramethyl-benzidine(TMB) to form blue oxidized TMB (TMBox). In the presence of nitrite, it further oxidizes TMBox to obtain yellow derivative products attributed to nitrite inducing diazotization reaction in TMBox. Based on this principle, a colorimetric and electrochemical sensing system was developed, and the ultra-sensitive multi-mode detection of nitrite was realized by combining RGB mode of smart phone, UV-Vis spectrum and electrochemical method. Compared with single signal detection, the multi-mode sensing system can realize self-validation to achieve more reliable detection results. What's more, the developed multi-mode sensing could quickly and sensitively detect nitrite in real sample, especially RGB mode of smart phone meeting the equipment limited areas, suggesting a broad application prospects in food safety.

Effect of Plasma-Treated Water with Magnesium and Zinc on Growth of Chinese Cabbage.

Nonthermal biocompatible plasma (NBP) is an emerging technology in the field of agriculture to boost plant growth. Plasma is a source of various gaseous reactive oxygen and nitrogen species (RONS) and has a promising role in agricultural applications, as the long-lived RONS (H2O2, NO2-, NO3-) in liquid activate signaling molecules in plant metabolism. Plasma-treated water (PTW) has an acidic pH of around 3 to 4, which may be detrimental to pH-sensitive plants. Innovative techniques for producing PTW with a pH value of 6 to 7 under neutral circumstances are desperately required to broaden the application range of NBP in agriculture. Furthermore, Pak Choi (Brassica campestris L.) is a Brassicaceae family green vegetable that has yet to be investigated for its response to NBP. In this work, we proposed an alternate method for neutralizing the pH of PTW by immersing metal ions (Mg2+ and Zn2+) in the PTW and observing its effect on Pak Choi. After synthesizing PTW with MECDBD, we analyzed germination rate and growth parameters, then seedlings for 42 days to show physiological, biochemical, and molecular levels. The germination rate was observed to be higher with PTW and more efficient when metal ions were present. Seedling length and germination rates were dramatically boosted when compared to DI water irrigation. Because of the increased chlorophyll and protein content, the plants responded to the availability of nitrogen by generating highly green leaves. Furthermore, we observed that PTW increases the expression of NR genes and GLR1 genes, which are further increased when metals are submerged in the PTW. Furthermore, PTW and PTW with metals reduced ABI5 and CHO1 which is associated with a growth inhibitor. According to this study, nonthermal plasma might be utilized to significantly improve seed germination and seedlings' development.

Single-atom boosted electrochemiluminescence via phosphorus doping of Fe-N/P-C catalysts.

Single-atom catalyst (SAC), one of the most attractive catalysts in the field of energy conversion and storage, was proven as efficient accelerator for luminol-dissolved oxygen electrochemiluminescence (ECL) via the catalysis of oxygen reduction reaction (ORR). In this work, we synthesized heteroatom doping SACs of Fe-N/P-C for the catalysis of cathodic luminol ECL. The doping of P could lower the reaction energy barrier of the OH* reduction, and promote catalytic efficiency toward ORR. The formation of reactive oxygen species (ROS) during ORR triggered cathodic luminol ECL. Greatly enhanced ECL emission catalyzed by SACs proved that Fe-N/P-C exhibited higher catalytic activity to ORR compared with Fe-N-C. Since the system was highly dependent on oxygen, an ultra-sensitive detection of a typical antioxidant, ascorbic acid, was achieved with detection limit of 0.03 nM. This study provides possibility to greatly enhance the performance of ECL platform through rational tailoring of SACs via heteroatom doping.

Effect of Plasma On-Time with a Fixed Duty Ratio on Reactive Species in Plasma-Treated Medium and Its Significance in Biological Applications.

Optimizing the therapeutic range of nonthermal atmospheric pressure plasma (NTAPP) for biomedical applications is an active research topic. For the first time, we examined the effect of plasma on-times in this study while keeping the duty ratio and treatment time fixed. We have evaluated the electrical, optical, and soft jet properties for two different duty ratios of 10% and 36%, using the plasma on-times of 25, 50, 75, and 100 ms. Furthermore, the influence of plasma on-time on reactive oxygen and nitrogen species (ROS/RNS) levels in plasma treated medium (PTM) was also investigated. Following treatment, the characteristics of (DMEM media) and PTM (pH, EC, and ORP) were also examined. While EC and ORP rose by raising plasma on-time, pH remained unchanged. Finally, the PTM was used to observe the cell viability and ATP levels in U87-MG brain cancer cells. We found it interesting that, by increasing the plasma on-time, the levels of ROS/RNS dramatically increased in PTM and significantly affected the viability and ATP levels of the U87-MG cell line. The results of this study provide a significant indication of advancement by introducing the optimization of plasma on-time to increase the efficacy of the soft plasma jet for biomedical applications.

A colorimetric smartphone-based sensor for on-site AA detection in tropical fruits using Fe-P/NC single-atom nanoenzyme.

Ascorbic acid is one of the important vitamins to maintain human life activities and plays an irreplaceable role in regulating human redox metabolism. Fresh fruit can provide plenty of AA to maintain human metabolic balance. Thus, it is great significant to develop a rapid and convenient method for detection of AA to evaluate the freshness and nutritional quality of fruits. In this work, Fe single-atom nanoenzyme (Fe-SAN) based colorimetric sensor assisted with smartphone was designed for rapid and on-site AA detection in tropical fruits. Firstly, Fe-SAN with high oxidase-mimicking activity was synthesized by using green tea leaves as sources of carbon and nitrogen and NaH2PO2 as P source to obtain Fe-P/NC SAN, in which P was used to reconstruct the distribution of electronic to enhance the oxidase-mimicking activity of Fe-SAN. Besides, the as-synthesized Fe-P/NC SAN with remarkable oxidase-like activities could oxidize 3,3́,5,5́-tetramethylbenzidine (TMB) to blue colored oxidized TMB. AA could inhibit the oxidation of TMB, leading to blue fading. Based on the above principle, colorimetric sensor integrated with smartphone RGB mode was fabricated and exhibited a good linear detection range (0.5-100 µM) and low detection limit of 0.315 µM for AA detection under optimal conditions. More importantly, the developed sensor could rapidly and accurately detect AA in real sample, such as pineapple, wax apple and mango. Therefore, this research provides a new cost-effective method for the efficient and exact detection of AA in tropical fruit, which has a broad application prospect.

Synthesis and characterization of copper oxide nanoparticles: its influence on corn (Z. mays) and wheat (Triticum aestivum) plants by inoculation of Bacillus subtilis.

Nanotechnology is now playing an emerging role in green synthesis in agriculture as nanoparticles (NPs) are used for various applications in plant growth and development. Copper is a plant micronutrient; the amount of copper oxide nanoparticles (CuONPs) in the soil determines whether it has positive or adverse effects. CuONPs can be used to grow corn and wheat plants by combining Bacillus subtilis. In this research, CuONPs were synthesized by precipitation method using different precursors such as sodium hydroxide (0.1 M) and copper nitrate (Cu(NO3)2) having 0.1 M concentration with a post-annealing method. The NPs were characterized through X-ray diffraction (XRD), scanning electron microscope (SEM), and ultraviolet (UV) visible spectroscopy. Bacillus subtilis is used as a potential growth promoter for microbial inoculation due to its prototrophic nature. The JAR experiment was conducted, and the growth parameter of corn (Z. mays) and wheat (Triticum aestivum) was recorded after 5 days. The lab assay evaluated the germination in JARs with and without microbial inoculation under CuONP stress at different concentrations (25 and 50 mg). The present study aimed to synthesize CuONPs and systematically investigate the particle size effects of copper (II) oxide (CuONPs) (< 50 nm) on Triticum aestivum and Z. mays. In our results, the XRD pattern of CuONPs at 500 °C calcination temperature with monoclinic phase is observed, with XRD peak intensity slightly increasing. The XRD patterns showed that the prepared CuONPs were extremely natural, crystal-like, and nano-shaped. We used Scherrer's formula to calculate the average size of the particle, indicated as 23 nm. The X-ray diffraction spectrum of synthesized materials and SEM analysis show that the particles of CuONPs were spherical in nature. The results revealed that the synthesized CuONPs combined with Bacillus subtilis used in a field study provided an excellent result, where growth parameters of Z. Mays and Triticum aestivum such as root length, shoot length, and plant biomass was improved as compared to the control group.

Switching on-off-on colorimetric sensor based on Fe-N/S-C single-atom nanozyme for ultrasensitive and multimodal detection of Hg2.

Single-atom nanozymes (SAzymes) as a new class of efficient nanozymes have attracted extensive research interest due to their high catalytic activity and specificity. However, it is challenging to develop a novel nanoenzyme with high activity, good stability and reproducibility. In this paper, the nitrogen and sulfur coordinated Fe-N/S-C SAzymes were synthesized using peanuts shells as carbon, nitrogen and sulfur source. It shows high oxidase-like activities due to the doping of S induced geometric and electronic effects, which is further confirmed by density functional theory calculations. The prepared Fe-N/S-C SAzymes with the remarkable oxidase-mimicking activity could oxidize TMB to blue oxTMB, but the GSH can inhibit the oxidation of TMB resulting in blue fading. However, when Hg2+ is added into above system, Hg2+-SH complexes are generated attributed to a high affinity between GSH and Hg2+, ultimately leading to blue recovery. Based on this phenomenon, we constructed a novel "on-off-on" colorimetric sensor for the simultaneous detection of GSH (off) and Hg2+ (on), and the signal is acquired by various modes such as naked eye, UV-Vis spectrometer and smartphone. The colorimetric detection mode based on a smartphone showed a good linear response from 10 to 80 µM for GSH with a detection limit of 3.92 µM, and for Hg2+ with a linear range of 1 nM-10 µM and LOD of 0.17 nM, which is more suitable for routine laboratory applications. More importantly, the proposed colorimetric sensor has been successfully applied to the detection of GSH and Hg2+ in real samples with good analytical performance. This work not only provides a simple and cost-effective method to detect GSH and Hg2+ but also makes a certain contribution to environmental protection.

Jasmonic acid: a key frontier in conferring abiotic stress tolerance in plants.

Abiotic stresses are the primary sources of crop losses globally. The identification of key mechanisms deployed and established by plants in response to abiotic stresses is necessary for the maintenance of their growth and persistence. Recent discoveries have revealed that phytohormones or plant growth regulators (PGRs), mainly jasmonic acid (JA), have increased our knowledge of hormonal signaling of plants under stressful environments. Jasmonic acid is involved in various physiological and biochemical processes associated with plant growth and development as well as plant defense mechanism against wounding by pathogen and insect attacks. Recent findings suggest that JA can mediate the effect of abiotic stresses and help plants to acclimatize under unfavorable conditions. As a vital PGR, JA contributes in many signal transduction pathways, i.e., gene network, regulatory protein, signaling intermediates and enzymes, proteins, and other molecules that act to defend cells from the harmful effects of various environmental stresses. However, JA does not work as an independent regulator, but acts in a complex signaling pathway along other PGRs. Further, JA can protect and maintain the integrity of plant cells under several stresses by up-regulating the antioxidant defense. In this review, we have documented the biosynthesis and metabolism of JA and its protective role against different abiotic stresses. Further, JA-mediated antioxidant potential and its crosstalk with other PGRs have also been discussed.

Uptake of heavy metal ions from aqueous media by hydrogels and their conversion to nanoparticles for generation of a catalyst system: two-fold application study.

Poly(methacrylic acid) (P(MAA)), poly(acrylamide) (P(AAm)) and poly(3-acrylamidopropyltrimethyl ammonium chloride) (P(APTMACl)) were synthesized as anionic, neutral and cationic hydrogels, respectively. The synthesized hydrogels have the ability to be used as absorbents for the removal of selected heavy metal ions such as Cu2+, Co2+, Ni2+ and Zn2+ from aqueous media. Absorption studies revealed that the absorption of metal ions by the hydrogels followed the order Cu2+ > Ni2+ > Co2+ > Zn2+. For the mechanism of absorption, both Freundlich and Langmuir absorption isotherms were applied. Metal ion entrapped hydrogels were treated using an in situ chemical reduction method in order to convert the metal ions into metal nanoparticles for the synthesis of hybrid hydrogels. The synthesis and morphology were confirmed using FT-IR and SEM, while the absorbed metal amounts were measured using TGA and AAS. The hybrid hydrogels were further used as catalysts for the reduction of macro (methylene blue, methyl orange and congo red) and micro (4-nitrophenol and nitrobenzene) pollutants from the aqueous environment. The catalytic performance and re-usability of the hybrid hydrogels were successfully investigated.