Melatonin mediated tolerance to benzalkonium chloride phytotoxicity through improved growth, photochemical reactions, and antioxidant system in wild-type and snat2 mutant Arabidopsis lines.

Melatonin (Mel) is a phytohormone that plays a crucial role in various plant processes, including stress response. Despite numerous studies on the role of Mel in stress resistance, its significance in plants exposed to benzalkonium chloride (BAC) pollution remains unexplored. BAC, a common antiseptic, poses a threat to terrestrial plants due to its widespread use and inefficient removal, leading to elevated concentrations in the environment. This study investigated the impact of BAC (0.5 mg L-1) pollution on wild-type Col-0 and snat2 knockout mutant Arabidopsis lines, revealing reduced growth, altered water relations, and gas exchange parameters. On the other hand, exogenous Mel (100 µM) treatments mitigated BAC-induced phytotoxicity and increased the growth rate by 1.8-fold in Col-0 and 2-fold in snat2 plants. snat2 mutant seedlings had a suppressed carbon assimilation rate (A) under normal conditions, but BAC contamination led to further A repression by 71% and 48% in Col-0 and snat2 leaves, respectively. However, Mel treatment on stressed plants was successful in improving Fv/Fm and increased the total photosynthesis efficiency by regulating photochemical reactions. Excessive H2O2 accumulation in the guard cells of plants exposed to BAC pollution was detected by confocal microscopy. Mel treatments triggered almost all antioxidant enzyme activities (except POX) in both Arabidopsis lines under stress. This enhanced antioxidant activity, facilitated by foliar Mel application, contributed to the alleviation of oxidative damage, regulation of photosynthesis reactions, and promotion of plant growth in Arabidopsis. In addition to corroborating results observed in many agricultural plants regarding the development of tolerance to environmental stresses, this study provides novel insights into the action mechanisms of Mel under the emerging pollutant benzalkonium chloride.

Exogenous curcumin mitigates As stress in spinach plants: A biochemical and metabolomics investigation.

The spinach (S. oleracea L.) was used as a model plant to investigate As toxicity on physio-biochemical processes, exploring the potential mitigation effect of curcumin (Cur) applied exogenously at three concentrations (1, 10, and 20 µM Cur). The employment of Cur significantly mitigated As-induced stress in spinach photosynthetic performance (Fv/Fm, Fo/Fm, and Fv/Fo). Moreover, the co-incubation of Cur with As improved physiological processes mainly associated with plant water systems affected by As stress by recovering the leaf's relative water content (RWC) and osmotic potential (ψπ) nearly to the control level and increasing the transpiration rate (E; 39-59%), stomatal conductivity (gs; 86-116%), and carbon assimilation rate (A; 84-121%) compared to As stressed plants. The beneficial effect of Cur in coping with As-induced stress was also assessed at the plant's oxidative level by reducing oxidative stress biomarkers (H2O2 and MDA) and increasing non-enzymatic antioxidant capacity. Untargeted metabolomics analysis was adopted to investigate the main processes affected by As and Cur application. A multifactorial ANOVA discrimination model (AMOPLS-DA) and canonical correlation analysis (rCCA) were employed to identify relevant metabolic changes and biomarkers associated with Cur and As treatments. The results highlighted that Cur significantly determined the accumulation of glucosinolates, phenolic compounds, and an increase in glutathione redox cycle activities, suggesting an overall elicitation of plant secondary metabolisms. Specifically, the correlation analysis reported a strong and positive correlation between (+)-dihydrokaempferol, L-phenylalanine (precursor of phenolic compounds), and serotonin-related metabolites with antioxidant activities (ABTS and DPPH), suggesting the involvement of Cur application in promoting a cross-talk between ROS signaling and phytohormones, especially melatonin and serotonin, working coordinately to alleviate As-induced oxidative stress. The modulation of plant metabolism was also observed at the level of amino acids, fatty acids, and secondary metabolites synthesis, including N-containing compounds, terpenes, and phenylpropanoids to cooperate with As-induced stress response.

Exploring traditional and modern approaches for extracting bioactive compounds from Ferulago trachycarpa.

For more than two millennia, Ferulago species have been revered as therapeutic herbs, maintaining their significance in present-day folk medicine practices. Therefore, the present study was conducted to investigate the phytochemical composition, inhibitory effects on metabolic enzymes, and possible therapeutic applications of F. trachycarpa, specifically focusing on its efficacy in diabetes management, anticholinergic effects, and antioxidant capabilities. The current investigation comprised an evaluation of a range of extracts acquired via conventional and modern methodologies, such as soxhlet (SOX), maceration (MAC) accelerated solvent extraction (ASE), homogenizer-assisted extraction (HAE), supercritical fluid extraction (SFE), microwave-assisted extraction (MW), and ultrasound-assisted extraction (UAE). Various techniques were employed to assess their antioxidant capacity and enzyme inhibition. Furthermore, the research utilized ultra-high performance liquid chromatography-MS/MS (UHPLC-MS/MS) to ascertain the principal phenolic compounds that are responsible for the antioxidant capacity observed in the various F. trachycarpa extracts. Among these, extracts from HAE, ASE, and MW revealed the most promise across all methodologies tested for their antioxidant potential. Furthermore, SFE and MAC extracts inhibited the most enzymes, including cholinesterases, tyrosinase, α -amylase, and α -glycosidase, indicating their potential as efficient natural treatments for several health-related issues.

The characterization of plant derived-carbon dots and its responses on chlorophyll a fluorescence kinetics, radical accumulation in guard cells, cellular redox state and antioxidant system in chromium stressed-Lactuca sativa.

Based on their chemical structure and catalytic features, carbon dots (CDs) demonstrate great advantages for agricultural systems. The improvements in growth, photosynthesis, nutrient assimilation and resistance are provided by CDs treatments under control or adverse conditions. However, there is no data on how CDs can enhance the tolerance against chromium toxicity on gas exchange, photosynthetic machinery and ROS-based membrane functionality. The present study was conducted to evaluate the impacts of the different concentrations of orange peel derived-carbon dots (50-100-200-500 mg L-1 CD) on growth, chlorophyll fluorescence, phenomenological fluxes between photosystems, photosynthetic performance, ROS accumulation and antioxidant system under chromium stress (Cr, 100 µM chromium (VI) oxide) in Lactuca sativa. CDs removed the Cr-reduced changes in growth (RGR), water content (RWC) and proline (Pro) content. Compared to stress, CD exposures caused an alleviation in carbon assimilation rate, stomatal conductance, transpiration rate, carboxylation efficiency, chlorophyll fluorescence (Fv/Fm) and potential photochemical efficiency (Fv/Fo). Cr toxicity disrupted the energy fluxes (ABS/RC, TRo/RC, ETo/RC and DIo/RC), quantum yields and, efficiency (ΨEo and φRo), dissipation of energy (DIo/RC) and performance index (PIABS and PItotal). An amelioration in these parameters was provided by CD addition to Cr-applied plants. Stressed plants had high activities of superoxide dismutase (SOD), peroxidase (POX) and ascorbate peroxidase (APX), which could not prevent the increase of H2O2 and lipid peroxidation (TBARS content). While all CDs induced SOD and catalase (CAT) in response to stress, POX and enzyme/non-enzymes related to ascorbate-glutathione (AsA-GSH) cycle (APX, monodehydroascorbate reductase (MDHAR) and dehydroascorbate reductase (DHAR), the contents of AsA and, GSH) were activated by 50-100-200 mg L-1 CD. CDs were able to protect the AsA regeneration, GSH/GSSG and GSH redox status. The decreases in H2O2 content might be attributed to the increased activity of glutathione peroxidase (GPX). Therefore, all CD applications minimized the Cr stress-based disturbances (TBARS content) by controlling ROS accumulation, antioxidant system and photosynthetic machinery. In conclusion, CDs have the potential to be used as a biocompatible inducer in removing the adverse effects of Cr stress in lettuce plants.

Hesperidin and chlorogenic acid mitigate arsenic-induced oxidative stress via redox regulation, photosystems-related gene expression, and antioxidant efficiency in the chloroplasts of Zea mays.

The ubiquitous metalloid arsenic (As), which is not essential, can be found extensively in the soil and subterranean water of numerous nations, raising substantial apprehensions due to its impact on both agricultural productivity and sustainability. Plants exposed to As often display morphological, physiological, and growth-related abnormalities, collectively leading to reduced productivity. Polyphenols, operating as secondary messengers within the intricate signaling networks of plants, assume integral functions in the acquisition of resistance to diverse environmental stressors, including but not limited to drought, salinity, and exposure to heavy metals. The pivotal roles played by polyphenols in these adaptive processes underscore their profound significance in plant biology. This study aims to elucidate the impact of hesperidin (HP) and chlorogenic acid (CA), recognized as potent bioactive compounds, on maize plants exposed to As. To achieve this objective, the study examined the physiological and biochemical impacts, including growth parameters, photosynthesis, and chloroplastic antioxidants, of HP (100 µM) and CA (50 µM) on Zea mays plants exposed to arsenate stress (AsV, 100 µM - Na2HAsO4⋅7H2O). As toxicity led to reductions in fresh weight (FW) and dry weight (DW) by 33% and 26%, respectively. However, the application of As+HP and As + CA increased FW by 22% and 40% and DW by 14% and 17%, respectively, alleviating the effects of As stress. As toxicity resulted in the up-regulation of PSII genes (psbA and psbD) and PSI genes (psaA and psaB), indicating a potential response to the re-formation of degraded regions, likely driven by the heightened demand for photosynthesis. Exogenous HP or/and CA treatments effectively counteracted the adverse effects of As toxicity on the photochemical quantum efficiency of PSII (Fv/Fm). H2O2 content showed a 23% increase under As stress, and this increase was evident in guard cells when examining confocal microscopy images. In the presence of As toxicity, the chloroplastic antioxidant capacity can exhibit varying trends, with either a decrease or increase observed. After the application of CA and/or HP, a significant increase was observed in the activity of GR, APX, GST, and GPX enzymes, resulting in decreased levels of H2O2 and MDA. Additionally, the enhanced functions of MDHAR and DHAR have modulated the redox status of ascorbic acid (AsA) and glutathione (GSH). The HP or CA-mediated elevated levels of AsA and GSH content further contributed to the preservation of redox homeostasis in chloroplasts facing stress induced by As. In summary, the inclusion of HP and CA in the growth medium sustained plant performance in the presence of As toxicity by regulating physiological and biochemical characteristics, chloroplastic antioxidant enzymes, the AsA-GSH cycle and photosynthesis processes, thereby demonstrating their significant potential to confer resistance to maize through the mitigation of As-induced oxidative damage and the safeguarding of photosynthetic mechanisms.

UHPLC-ESI-QTOF-MS metabolite profiles of different extracts from Pelargonium endlicherianum parts and their biological properties based on network pharmacological approaches.

In the present study, we aimed to investigate the chemical profiles and biological activities of different extracts (ethyl acetate, dichloromethane, ethanol, and water) of Pelargonium endlicherianum parts (aerial parts and roots). Free radical scavenging, reducing power, phosphomolybdenum, and metal chelating were assayed for antioxidant properties. To detect enzyme inhibitory properties, cholinesterase, amylase, glucosidase, and tyrosinase were chosen as target enzymes. The ethanol extract of the aerial parts contained higher amounts of total bioactive compounds (120.53 mg GAE/g-24.46 mg RE/g). The ethanol and water extracts of these parts were tentatively characterized by UHPLC-ESI-QTOF-MS and 95 compounds were annotated. In addition, the highest acetylcholiesterase (3.74 mg GALAE/g) and butyrylcholinesterase (3.92 mg GALAE/g) abilities were observed by the ethanol extract of roots. The water extract from aerial parts exhibited the most pronounced inhibitory effects on multiple cancer cell lines, especially A549 (IC50: 23.2 µg/mL) and HT-29 (IC50: 27.43 µg/mL) cells. Using network pharmacology, P. endlicherianum compounds were studied against cancer, revealing well-connected targets such as epidermal growth factor receptor (EGFR), phosphoinositide-3-kinase (PI3K), AKT, receptor tyrosine-protein kinase erbB-2, and growth factor receptor bound protein 2 (GRB2) with significant impact on cancer-related pathways. The results could open a new path from natural treasure to functional applications with P. endlicherianum and highlight a new study on other uninvestigated Pelargonium species.

Graphene oxide-based aerogel stimulates growth, mercury accumulation, photosynthesis-related gene expression, antioxidant efficiency and redox status in wheat under mercury exposure.

Mercury (Hg) pollution is a global concern in cropland systems. Hg contamination causes a disruption in the growth, energy metabolism, redox balance, and photosynthetic activity of plants. In the removal of Hg toxicity, a recent critical strategy is the use of aerogels with biodegradability and biocompatibility. However, it is unknown how graphene oxide-based aerogels stimulate the defense systems in wheat plants exposed to Hg toxicity. Therefore, in this study, the photosynthetic, genetic, and biochemical effects of reduced graphene oxide aerogel treatments (gA; 50-100-250 mg L-1) were examined in wheat (Triticum aestivum) under Hg stress (50 µM HgCl2). The relative growth rate (RGR) significantly decreased (84%) in response to Hg stress. However, the reduced RGR and water relations (RWC) of wheat were improved by gA treatments. The impaired gas exchange levels (stomatal conductance, carbon assimilation rate, intercellular CO2 concentrations, and transpiration rate) caused by stress were reversed under Hg plus gAs. Additionally, stress hampered chlorophyll fluorescence (Fv/Fo, Fv/Fm), and under Hg toxicity the expression of psaA genes was reduced (>0.4-fold), but psaB gene was significantly up-regulated (>3-fold) which are the genes involved in PSI. By increasing expression patterns of both genes relating to PSI, gAs reversed the adverse consequences on Fv/Fo and Fv/Fm in the presence of excessive Hg concentration. The activities of glutathione S-transferase (GST), glutathione reductase (GR), catalase (CAT), ascorbate peroxidase (APX) and dehydroascorbate reductase (DHAR) decreased under Hg toxicity. On the other hand, the activities of superoxide dismutase (SOD), APX, GST, and glutathione peroxidase (GPX) increased following gA treatments against stress, leading to the successful elimination of toxic levels of H2O2 and lipid peroxidation (TBARS content) by decreasing the levels by about 30%, and 40%, respectively. By modulating enzyme/non-enzyme activity/contents including the AsA-GSH cycle, gAs contributed to the protection of the cellular redox state. Most important of all, gA applications were able to reduce Hg intake by approximately 66%. Therefore, these results showed that gAs were effective in highly inhibiting Hg uptake and could significantly increase wheat tolerance to toxicity by eliminating Hg-induced oxidative damage and inhibiting metabolic processes involved in photosynthesis. The findings obtained from the study provide a new perspective on the alleviation roles of reduced graphene oxide aerogels as an effective adsorbent for decreasing damages of mercury toxicity in wheat plants.

The exogenous application of naringenin and rosmarinic acid modulates functional traits in Lepidium sativum.

BACKGROUND: Phenolic modulators have attracted attention for their potential in shaping functional traits in plants. This work investigated the impact of naringenin (Nar) and rosmarinic acid (RA) on the functional properties of Lepidium sativum leaves and roots. RESULTS: Untargeted metabolomics identified a diverse phenolic profile, including flavonoids, phenolic acids, low molecular weight phenolics, lignans, and stilbenes. Cluster, analysis of variance multiblock orthogonal partial least squares (AMOPLS), and orthogonal projection to latent structures discriminant analysis (OPLS-DA) multivariate analyses confirmed tissue-specific modulation of bioactive compounds. The tissue was the hierarchically most influential factor, explaining 27% of observed variability, while the treatment and their interaction were statistically insignificant. Thereafter, various in vitro assays were employed to assess antioxidant capacity, including 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) radical scavenging activity, cupric ion reducing antioxidant capacity (CUPRAC), and ferric ion reducing antioxidant power (FRAP), metal chelating ability, and phosphomolybdenum (PMD) assays. Extracts were also tested for inhibitory effects on cholinesterase, amylase, glucosidase, and tyrosinase enzymes. RA application positively impacted antioxidant and enzyme inhibitory activities, holding valuable implications in shaping the health-promoting properties of L. sativum. CONCLUSION: The untargeted metabolomics analysis showed a significant tissue-dependent modulation of bioactive compounds, determining no synergistic effect between applying phenolic compounds in combination. Specifically, the sole application of RA increased anthocyanins and hydroxyphenyl propanoic acid content on leaves, which was strictly related to enhancing the biological activities. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Extractions of aerial parts of Hippomarathrum scabrum with conventional and green methodologies: Chemical profiling, antioxidant, enzyme inhibition, and anti-cancer effects.

Hippomarathrum scabrum L. is an endemic medicinal plant in Turkey; however, there have been few studies investigating the phytochemistry and biological properties of these plants has not been investigated. The aim of this work is to determine the chemical composition of different extracts (extracts obtained by using supercritical carbon dioxide extraction, accelerated solvent extraction, homogenizer-assisted extraction, microwave-assisted extraction, and ultrasound-assisted extraction from Hippomarathrum scabrum L., and evaluate their biological properties. The analysis revealed that 5-O-caffeoylquinic acid, rutin, and isorhamnetin 3-O-rutinoside were the main bioactive compounds. The extract obtained by accelerated extraction contains the highest concentration of 5-O-Caffeoylquinic acid (7616.74 ± 63.09 mg/kg dry extract) followed by the extract obtained by homogenizer-assisted extraction (6682.53 ± 13.04 mg/kg dry extract). In antioxidant tests, all extracts expressed significant antioxidant activity. Also, cytotoxic and anticancer effects of these plant extracts were detected in the human prostate cancer cell line. Intrinsic apoptotic genes were up-regulated and anti-apoptotic genes were down-regulated in human prostate cancer cells after inhibition concentration dose treatment. The findings are promising, and suggest the use of these plant extracts could be used as natural sources with different biological activities, as well as anticancer agents.

Polyvinylpyrrolidone-coated copper nanoparticles dose-dependently conferred tolerance to wheat under salinity and/or drought stress by improving photochemical activity and antioxidant system.

Copper (Cu) is one of the essential micronutrients for plants and has been used extensively in agricultural applications from the past to the present. However, excess copper causes toxic effects such as inhibiting photosynthesis, and disrupting biochemical processes in plants. Nanotechnology applications have offered a critical method for minimizing adverse effects and improving the effectiveness of copper nanoparticles. For this purpose, this study investigated the physiological and biochemical effects of polyvinylpyrrolidone (PVP)-coated Cu nanoparticles (PVP-Cu NP, N1, 100 mg L-1; N2, 400 mg L-1) in Triticum aestivum under alone or combined with salt (S, 150 mM NaCl) and/or drought (D, %10 PEG-6000) stress. Salinity and water deprivation caused 51% and 22% growth retardation in wheat seedlings. The combined stress condition (S + D) resulted in an approximately 3-fold reduction in the osmotic potential of the leaves. PVP-Cu NP treatments to plants under stress, especially N1 dose, were effective in restoring growth rate and regulating water relations. All stress treatments limited gas exchange in stomata and suppressed the maximal quantum yield of PSII (Fv/Fm). More than 50% improvement was observed in stomatal permeability and carbon assimilation rate under S + N1 and S + N2 applications. Examination of OJIP transient parameters revealed that N1 treatments protected photochemical reactions by reducing the dissipated energy flux (DIo/RC) in drought and S + D conditions. Exposure to S and/or D stress caused high hydrogen peroxide (H2O2) accumulation and lipid peroxidation in wheat leaves. The results indicated that S + N1 and S + N2 treatments reduced oxidative damage by stimulating the activities of antioxidant enzymes superoxide dismutase (SOD), peroxidase (POX), and ascorbate peroxidase (APX). Although similar effects were observed at D and S + D conditions with 100 mg L-1 PVP-Cu NP treatments (N1), the curative effect of the N2 dose was not observed. In D + N1 and S + D + N1 groups, AsA regeneration and GSH redox status were maintained by triggering APX, GR, and other enzyme activities belonging to the AsA-GSH cycle. In these groups, N2 treatment did not contribute to the availability of enzymatic and non-enzymatic antioxidants. As a result, this study revealed that N1 dose PVP-Cu NP application was successful in providing stress tolerance and limiting copper-induced adverse effects under all stress conditions.

Exploring for HPLC-MS/MS Profiles and Biological Activities of Different Extracts from Allium lycaonicum Siehe ex Hayek from Turkey Flora.

The present study was designed to determine the phenolic constituents, antioxidant, and enzyme inhibition activities of aerial parts and bulbs of Allium lycaonicum (family Amaryllidaceae). Extracts were prepared by maceration and Soxhlet/infusion using hexane, methanol, and water as extraction solvents. Generally, extracts from the aerial parts showed higher total phenolic and individual components and antioxidant activity than their respective bulb extracts. Maceration with water was the best to extract total phenolic content from the aerial parts (29.00 mg gallic acid equivalents (GAE)/g), while the Soxhlet extraction with hexane (22.29 mg GAE/g) was the best for the bulb. Maceration with methanol recovered the highest total flavonoid content from both the aerial parts (41.95 mg (rutin equivalents (RE)/g) and bulb (1.83 mg RE/g). Polar extracts of aerial parts were characterized by higher abundance of kaempferol-3-glucoside (≤20,624.27 µg/mg), hyperoside (≤19,722.76 µg/g), isoquercitrin (≤17,270.70 µg/g), delphindin-3,5-diglucoside (≤14,625.21 µg/g), and rutin (≤10,901.61 µg/g) than the bulb. Aerial parts' aqueous extract, prepared by maceration, exerted the highest anti-ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical activity (64.09 mg trolox equivalents (TE)/g), Cu++ (83.03 mg TE/g) and Fe+++ (63.03 mg TE/g) reducing capacity while that prepared by infusion recorded the highest anti-DPPH (2,2-diphenyl-1-picrylhydrazyl) radical (31.70 mg TE/g) and metal chelating (27.66 mg EDTAE/g) activities. The highest total antioxidant activity (1.46 mmol TE/g) was obtained by maceration of the bulb with water. Extracts obtained by organic solvents showed remarkable enzyme inhibition properties against the tested enzymes. Soxhlet extraction of the bulb with hexane and methanol recorded the highest acetylcholinesterase inhibition (4.75 mg galanthamine equivalents (GALAE)/g) and tyrosinase inhibition (139.95 mg kojic acid equivalents/g) activities, respectively. Extracts obtained by maceration of the bulb with methanol and the aerial parts with hexane exerted the highest glucosidase inhibition (3.25 mmol acarbose equivalents/g) and butyrylcholinesterase inhibition (20.99 mg GALAE/g) activities, respectively. These data indicated that A. lycaonicum is a source of bioactive molecules with potential antioxidant and enzyme inhibition properties. Nonetheless, the extracts obtained through various solvents and extraction techniques showed variations in their phytoconstituent composition and biological properties.

A Comparative Study on UHPLC-HRMS Profiles and Biological Activities of Inula sarana Different Extracts and Its Beta-Cyclodextrin Complex: Effective Insights for Novel Applications.

Within this particular framework, the extracts obtained from Inula sarana using a variety of solvents, included n-hexane, ethyl acetate, dichloromethane (DCM), 70% ethanol, ethanol, and water. The extracts obtained from n-hexane, ethyl acetate, and DCM were then subjected to a specific method for their incorporation into ß-cyclodextrin (ß-CD). The establishment of complex formation was validated through the utilization of scanning electron microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). The identification of phytochemical components was executed using UHPLC-HRMS. Furthermore, the total phenolic and flavonoid content was evaluated using the Folin-Ciocalteu assay and the AlCl3 method. Subsequently, the determination of antioxidant capacity was conducted utilizing DPPH, ABTS, CUPRAC, Frap, PBD, and MCA assays. The enzyme inhibitory activities of the samples (extracts and ß-CD complexes) were also examined by AChE, BChE, tyrosinase, α-glucosidase, and α-amylase. The findings indicated that water and 70% ethanol extracts contained the highest phenolic content. One hundred and fourteen bioactive compounds were identified by UHPLC-HRMS analysis. This study unveiled a substantial array of flavonoids, phenolic acid-hexosides and caffeoylhexaric acids within I. sarana, marking their initial identification in this context. Among the various extracts tested, the 70% ethanol extract stood out due to its high flavonoid content (jaceosidin, cirsiliol, and eupatilin) and hydroxybenzoic and hydroxycinnamic acid hexosides. This extract also displayed notably enhanced antioxidant activity, with ABTS, CUPRAC, and FRAP test values of 106.50 mg TE/g dry extract, 224.31 mg TE/g dry extract, and 110.40 mg TE/g, respectively. However, the antioxidant values of the complex extracts with ß-CD were generally lower than those of the pure extracts, an observation warranting significant consideration. In terms of enzyme inhibition activity, the ethanol and 70% ethanol extracts exhibited higher inhibitory effects on AChE, tyrosinase, and α-glucosidase. Conversely, n-hexane displayed stronger inhibitory activity against BChE. The ethyl acetate extract demonstrated elevated amylase inhibitory activity. However, the antioxidant values of the complex extracts with ß-CD were generally lower than those of the pure extracts, a noteworthy observation, while water and extracts from the I. sarana complex with ß-CD exhibited minimal or negatable inhibitory activity against specific enzymes.

Responses of salicylic acid encapsulation on growth, photosynthetic attributes and ROS scavenging system in Lactuca sativa exposed to polycyclic aromatic hydrocarbon pollution.

Salicylic acid (SA) is a phytohormone that plays a key role in the regulation of the defense response against environmental variables in plants, and it provides increased yield and stress tolerance when exogenously applied to plants as a growth regulator. The role of SA-mediated signals in abiotic stress tolerance varies according to the species, stressor, application method, and dose. This study investigated the effects of salicylic acid (SA, 0.1 mg ml-1) or ß-cyclodextrin encapsulated salicylic acid (e-SA, 0.1 mg ml-1) treatments on growth parameters, gas exchange, photosynthesis efficiency, and antioxidant capacity in lettuce seedlings exposed to polycyclic aromatic hydrocarbon pollution. Fluorene (FLN, 100 mg L-1) contamination resulted in a 27% growth rate and a 14% water content reduction in lettuce leaves. Significant suppressions of stomatal conductance, carbon assimilation, and PSII photochemistry were detected in plants under stress. FLN + SA and FLN + e-SA treatments regulated plant-water relations by stimulating proline accumulation and relieving stomatal limitations. As indicated by the high Fv/Fm ratio, photosynthesis efficiency was recovered in FLN + SA and FLN + e-SA group plants. FLN stress caused high oxidative stress in lettuce leaves and increased lipid peroxidation level by 40%. However, especially e-SA application to plants under stress, increased SOD activity by 3-fold and CAT activity by 80% and was successful in preventing H2O2 accumulation and lipid peroxidation. Both SA and e-SA treatments partially activated the AsA-GSH cycle. As a result, direct SA application was effective in mitigating stress-induced physiological limitations with high SA accumulation in the tissues, while encapsulated SA treatment was more effective in regulating photosynthetic and biochemical reactions, alleviating oxidative damage by activating the antioxidant defense, and promoting growth under stress with moderate SA accumulation.

Polyamine, 1,3-diaminopropane, regulates defence responses on growth, gas exchange, PSII photochemistry and antioxidant system in wheat under arsenic toxicity.

The metalloid arsenic (As) is extremely hazardous to all living organisms, including plants. Pollution with As is very detrimental to the photosynthetic machinery, cell division, energy generation, and redox status. In order to cope with stress, the use of growth regulators such as polyamines (PA), which strengthen the antioxidant system of plants, has become widespread in recent years. PAs can modulate the plant growth through basic mechanisms common to all living organisms, such as membrane stabilization, free radical scavenging, deoxyribonucleic acid (DNA), ribonucleic acid (RNA) and protein synthesis, enzyme activities and second messengers. However, the effect of 1,3- diaminopropane (Dap), which is a product of PA catabolism, is not clear enough in plants exposed to As toxicity. In the current study, the different concentrations of 1,3-diaminopropane (0.1, 0.5 and 1 mM Dap) were hydroponically treated to wheat (Triticum aestivum) under arsenic stress (100 µM As) and then relative growth rate (RGR), relative water content (RWC), proline content (Pro), gas exchange parameters, PSII photochemistry, chlorophyll fluorescence kinetics, antioxidant activity and lipid peroxidation were assessed. RGR, RWC, osmotic potential and Pro content decreased in As-applied plants. The inhibition of these parameters could be reversed by Dap treatments. Besides, Dap applications mitigated the As toxicity-induced suppression on chlorophyll fluorescence (Fv/Fm, Fv/Fo and Fo/Fm) and the performance of PSII photochemistry. As impaired the balance on antioxidant capacity by decreased activities of catalase (CAT), peroxidase (POX), glutathione peroxidase (GPX), ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), and the contents of ascorbate (AsA) and glutathione (GSH) and then lipid peroxidation (TBARS content) increased. In the presence of Dap under As stress, the plants exhibited an increase in superoxide dismutase (SOD), POX, and GPX. Dap treatments contributed to the maintenance of cellular redox state (AsA/DHA and GSH/GSSG) by regulating the activities/contents of enzyme/non-enzyme involved in the AsA-GSH cycle. After Dap applications against stress, ROS accumulation (H2O2 content) and lipid peroxidation (TBARS) were effectively reduced. The findings showed that by eliminating As-induced oxidative damage and protecting the biochemical processes of photosynthesis, Dap treatments have a substantial potential to give resistance to wheat.

Protective role of quercetin and kaempferol against oxidative damage and photosynthesis inhibition in wheat chloroplasts under arsenic stress.

Arsenic (As) toxicity negatively impacts plant development, limits agricultural production, and, by entering the food chain, endangers human health. Studies on the use of natural and bioactive molecules in increasing plants' resistance to abiotic stressors, such as As, have gained increasing attention in the last few years. Flavonols are plant secondary metabolites with high potential in stress tolerance due to their roles in signal transmission. Therefore, the focus of this study was to examine the effects of two flavonols, quercetin (Q, 25 µM) and kaempferol (K, 25 µM), on growth parameters, photosynthesis, and chloroplastic antioxidant activity in wheat leaves under As stress (100 µM). As stress reduced the relative growth rate by 50% and relative water content by 25% in leaves. However, applying Q and/or K alleviated the As-induced suppression of growth and water relations. Exogenous phenolic treatments reversed the effects of As toxicity in photochemistry and maintained the photochemical quantum efficiency of the Photosystem II (Fv /Fm ). As exposure increased, the H2 O2 content in wheat chloroplasts by 42% and high levels of H2 O2 accumulation were also observed in guard cells in confocal microscopy images. Analysis of the chloroplastic antioxidant system has shown that Q and K applications increase the activity of antioxidant enzymes, including superoxide dismutase, peroxidase, and ascorbate peroxidase. Phenolic applications have induced the ascorbate-glutathione (AsA-GSH) cycle in charge of the protection of the cellular redox balance in different ways. It has been determined that Q triggers the AsA renewal, and K maintains the GSH pool. As a result, Q and K applications provide tolerance to wheat plants under As stress by increasing the chloroplastic antioxidant system activity and protecting photosynthetic reactions from oxidative damage. This study reveals the potential use of plant phenolic compounds in agricultural systems as a biosafe strategy to enhance plant stress tolerance, hence increasing yield.

Halotolerant plant growth-promoting bacteria, Bacillus pumilus, modulates water status, chlorophyll fluorescence kinetics and antioxidant balance in salt and/or arsenic-exposed wheat.

Seed priming is an effective and novel technique and the use of eco-friendly biological agents improves the physiological functioning in the vegetative stage of plants. This procedure ensures productivity and acquired stress resilience in plants against adverse conditions without contaminating the environment. Though the mechanisms of bio-priming-triggered alterations have been widely explained under induvial stress conditions, the interaction of combined stress conditions on the defense system and the functionality of photosynthetic apparatus in the vegetative stage after the inoculation to seeds has not been fully elucidated. After Bacillus pumilus inoculation to wheat seeds (Triticum aestivum), three-week-old plants were hydroponically exposed to the alone and combination of salt (100 mM NaCl) and 200 µM sodium arsenate (Na2HAsO4·7H2O, As) for 72 h. Salinity and As pollutant resulted in a decline in growth, water content, gas exchange parameters, fluorescence kinetics and performance of photosystem II (PSII). On the other hand, the seed inoculation against stress provided the alleviation of relative growth rate (RGR), relative water content (RWC) and chlorophyll fluorescence. Since there was no effective antioxidant capacity, As and/or salinity caused the induction of H2O2 accumulation and thiobarbituric acid reactive substances content (TBARS) in wheat . The inoculated seedlings had a high activity of superoxide dismutase (SOD) under stress. B. pumilis decreased the NaCl-induced toxic H2O2 levels by increasing peroxidase (POX) and enzymes/non-enzymes related to ascorbate-glutathione (AsA-GSH) cycle. In the presence of As exposure, the inoculated plants exhibited an induction in CAT activity. On the other hand, for H2O2 scavenging, the improvement in the AsA-GSH cycle was observed in bacterium priming plants plus the combined stress treatment. Since B. pumilus inoculation reduced H2O2 levels against all stress treatments, lipid peroxidation subsequently decreased in wheat leaves. The findings obtained from our study explained that the seed inoculation with B. pumilus provided an activation in the defense system and protection in growth, water status, and gas exchange regulation in wheat plants against the combination of salt and As.

Glutamate, Humic Acids and Their Combination Modulate the Phenolic Profile, Antioxidant Traits, and Enzyme-Inhibition Properties in Lettuce.

Lettuce (Lactuca sativa L., Asteraceae) is a popular vegetable leafy crop playing a relevant role in human nutrition. Nowadays, novel strategies are required to sustainably support plant growth and elicit the biosynthesis of bioactive molecules with functional roles in crops including lettuce. In this work, the polyphenolic profile of lettuce treated with glutamic acid (GA), humic acid (HA), and their combination (GA + HA) was investigated using an untargeted metabolomics phenolic profiling approach based on high-resolution mass spectrometry. Both aerial and root organ parts were considered, and a broad and diverse phenolic profile could be highlighted. The phenolic profile included flavonoids (anthocyanins, flavones, flavanols, and flavonols), phenolic acids (both hydroxycinnamics and hydroxybenzoics), low molecular weight phenolics (tyrosol equivalents), lignans and stilbenes. Overall, GA and HA treatments significantly modulated the biosynthesis of flavanols, lignans, low molecular weight phenolics, phenolic acids, and stilbene. Thereafter, antioxidant capacity was evaluated in vitro with 2,2-diphenyln-1-picrylhydrazyl (DPPH), 2,2'-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP), and cupric ion reducing antioxidant capacity (CUPRAC) assays. In addition, this study examined the inhibitory properties of enzymes, including acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), tyrosinase, alpha-amylase, and alpha-glucosidase. Compared to individual treatments, the combination of GA + HA showed stronger antioxidant abilities in free radical scavenging and reducing power assays in root samples. Moreover, this combination positively influenced the inhibitory effects of root samples on AChE and BChE and the tyrosinase inhibitory effect of leaf samples. Concerning Pearson's correlations, antioxidant and enzyme inhibition activities were related to phenolic compounds, and lignans in particular correlated with radical scavenging activities. Overall, the tested elicitors could offer promising insights for enhancing the functional properties of lettuce in agricultural treatments.

Chemical Characterization and Multidirectional Biological Effects of Different Solvent Extracts of Arum elongatum: in Vitro and in Silico Approaches.

Arum elongatum (Araceae) is widely used traditionally for the treatment of abdominal pain, arterial hypertension, diabetes mellitus, rheumatism and hemorrhoids. This study investigated the antioxidant properties, individual phenolic compounds, total phenolic and total flavonoid contents (HPLC/MS analysis), reducing power and metal chelating effects of four extracts obtained from A. elongatum (ethyl acetate (EA), methanol (MeOH), methanol/water (MeOH/water) and infusion). The inhibitory activity of the extracts were also determined against acetylcholinesterase, butyrylcholinesterase, tyrosinase, amylase and glucosidase enzymes. The MeOH/water extracts contained the highest amount of phenolic contents (28.85 mg GAE/g) while the highest total flavonoid content was obtained with MeOH extract (36.77 mg RE/g). MeOH/water demonstrated highest antioxidant activity against DPPH⋅ radical at 38.90 mg Trolox equivalent per gram. The infusion extract was the most active against ABTS+ ⋅ (133.08 mg TE/g). MeOH/water extract showed the highest reducing abilities with the CUPRAC value of 102.22 mg TE/g and the FRAP value of 68.50 mg TE/g. A strong metal chelating effect was observed with MeOH/water extract (35.72 mg EDTAE/g). The PBD values of the extracts ranged from 1.01 to 2.17 mmol TE/g. EA extract displayed the highest inhibitory activity against AChE (2.32 mg GALAE/g), BChE (3.80 mg GALAE/g), α-amylase (0.56 mmol ACAE/g) and α-glucosidase (9.16 mmol ACAE/g) enzymes. Infusion extract was the most active against tyrosinase enzyme with a value of 83.33 mg KAE/g. A total of 28 compounds were identified from the different extracts. The compounds present in the highest concentration were chlorogenic acids, 4-hydroxybenzoic acid, caffeic acid, p-coumaric acid, ferulic acid, isoquercitrin, delphindin 3,5-diglucoside, kaempferol-3-glucoside and hyperoside. The biological activities of A. elongatum extracts could be due to the presence of compounds such as gallic acid, chlorogenic acids, ellagic acid, epicatechin, catechin, kaempferol, 4-hydroxybenzoic acid, caffeic acid, p-coumaric acid, ferulic acid, quercetin, isoquercitrin, and hyperoside. Extracts of A. elongatum showed promising biological activities which warrants further investigations in an endeavor to develop biopharmaceuticals.

Phytochemical Profile and Biological Activities of Different Extracts of Three Parts of Paliurus spina-christi: A Linkage between Structure and Ability.

Paliurus spina-christi Mill., a member of the Rhamnaceae family, is a traditionally used medicinal plant in the management of a panoply of human ailments. The current research focused on its phytochemical profile and biological properties evaluated by its antioxidant and enzyme inhibitory properties. The methanol extract was found to be the most effective antioxidant as evidenced by its DPPH and ABTS scavenging activities, cupric and ferric reducing power (CUPRAC and FRAP), and high activity in phosphomolybdenum (PBD) assay, and also displayed the highest anti-tyrosinase activity. The n-hexane extract was the most effective AChE inhibitor (8.89 ± 0.08 mg GALAE/g) followed by the methanol (8.64 ± 0.01 mg GALAE/g) while the latter showed the highest BChE inhibition (2.50 ± 0.05 mg GALAE/g). Among the different solvent extracts of the stem, the methanolic extract showed highest antioxidant activity in the following assays: DPPH (909.88 ± 4.25 mg TE/g), ABTS (3358.33 ± 51.14 mg TE/g), CUPRAC (781.88 ± 16.37 mg TE/g), FRAP (996.70 ± 47.28 mg TE/g), and PBD (4.96 ± 0.26 mmol TE/g), while the dichloromethane extract showed the highest MCA (28.80 ± 0.32 mg EDTAE/g). The methanol extracts revealed the highest TPC and TFC among the different solvents used, and as for plant part, the stem extracts had the highest TPC ranging from 22.36 ± 0.26 to 121.78 ± 1.41 (mg GAE/g), while the leaf extracts showed the highest TFC ranging from 8.43 ± 0.03 to 75.36 ± 0.92 (mg RE/g). Our findings tend to provide additional scientific evidence on the biological and chemical activities of P. spina-christi, which may serve as a source of naturally occurring bioactive chemicals with potential biomedical applications.

Responses of individual and combined polystyrene and polymethyl methacrylate nanoplastics on hormonal content, fluorescence/photochemistry of chlorophylls and ROS scavenging capacity in Lemna minor under arsenic-induced oxidative stress.

Nanoplastics alter the adverse impacts of hazardous contaminants such as heavy metals by changing their adsorption and accumulation. Few findings are available on the interaction between nanoplastic and heavy metals in plants. However, there is no report on the mechanisms for removing metal stress-mediated oxidative damage by the combination treatments of nanoplastics. To address this lack of information, polystyrene nanoplastic (PS, 100 mg L-1) and polymethyl methacrylate (PMMA, 100 mg L-1) were hydroponically applied to Lemna minor exposed to arsenate (As, 100 µM) for 7 days. PS or PMMA caused a reduction in the contents of N, P, K, Ca, Mg and Mn, but the improved contents were detected in the presence of PS or PMMA plus As stress. The hormone contents (auxin, gibberellic acid, cytokinin, salicylic acid and jasmonic acid) reduced by stress were re-arranged through PS or PMMA applications. Based on chlorophyll efficiency, fluorescence kinetics and performance of PSII, the impaired photosynthesis by As stress was improved via PS or PMMA applications. This alleviation did not continue under the combined form of PS and PMMA in As-applied plants. All analyzed antioxidant activity (superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), ascorbate peroxidase (APX), glutathione reductase (GR), glutathione S-transferase (GST), glutathione peroxidase (GPX), monodehydroascorbate reductase (MDHAR) and dehydroascorbate reductase (DHAR)) decreased or unchanged under As, PS or PMMA. Due to the inactivation of the defense system, L. minor had high levels of hydrogen peroxide (H2O2) and thiobarbituric acid reactive substances (TBARS), showing lipid peroxidation. After As toxicity, induvial applications of PS or PMMA indicated the activated enzyme capacity (SOD, POX, GST and GPX) and upregulated AsA/DHA, GSH/GSSG and redox state of GSH, which facilitated the removal of radical accumulation. The efficiency of the antioxidant system in As + PS + PMMA-applied L. minor was not enough to remove damage induced by As stress; hereby, TBARS and H2O2 contents were similar to the As-treated group. Our findings from alone or combined application of PS and PMMA provide new information to advance the tolerance mechanism against As exposure in L. minor.