Non-enzymatic Activity Research Articles

Screening and characterization of bioactive compounds from two epiphytic microlichen and evaluation of their in vitro antioxidant activity

BackgroundLichens in symbiosis produce a wide range of primary and secondary fine compounds in extreme environmental conditions that have a broad range of biological properties as well as antioxidant potential and can be used in future pharmaceuticals as a natural source of antioxidant molecules.ResultsThe two microlichen species collected are identified based on morphological and molecular techniques; further studies are carried out by analyzing phytochemicals (FTIR, GC MS), and antioxidant assays are evaluated. The non-enzymatic antioxidant activity is evaluated by DPPH and FRAP assays. The methanol extract of both lichens showed virtuous DPPH scavenge with IC50 of P. nitida (125.76 ± 0.023 µg/ml) and G. scripta IC50 (176.90 ± 0.058 µg/ml). FRAP activity was prominent in the methalonic extract. The enzymatic antioxidant activity is observed by SOD and catalase activity. The cytosolic (Cu–Zn-SOD and Fe-SOD) and mitochondrial SOD (Mn-SOD) are detected in lichens, though P. nitida shows mitochondrial Mn-SOD and cytosolic Cu–Zn-SOD and Fe-SOD, whereas G. scripta has a single cytosolic Cu–Zn-SOD; however, two isoforms of catalase were reported. GC–MS analysis screened bioactive metabolites such as phenols, Quinons, heterocyclic compounds, benzofurans, fatty acids, pyrans, carboxylic acid, aliphatic aldehydes, organic alcohol, fluorinated aliphatic substances, ketones, terpenes and fatty alcohols in P. nitida, whereas, in G. scripta screened fatty acids, alcohols, hydrocarbons, carbonyl compounds, polyols, terpenes, glycosides, phenols, and sugar alcohols detected in the chromatogram peak. FTIR analysis revealed functional groups like Alcohols, Amines, Amides, Alkanes, Aldehydes, Carboxylic acid, Alkynes, Esters, Ketones, Anhydrides, Acid chlorides, Alkenes, Aromatic compounds, Nitro compounds, Alkyl and Aryl Halides in both lichens.ConclusionsThe results obtained in the present study proved that P. nitida and G. scripta have promising antioxidant activity owing to the presence of polyphenols and terpenes, as evidenced by DPPH and FRAP assay along with enzymatic analysis (SOD and CAT). Thus both the lichens may be used as natural sources of new bioactive molecules having pharmaceutical interest.

Morpho-physiological and metabolites alteration in the susceptible and tolerant genotypes of sesame under waterlogging stress and post-waterlogging recovery

Among the oil-seed crops, Sesamum indicum L. is an important nutritionally rich crop, well adapted to grow in semi-arid regions. Waterlogging stress adversely affects the growth of sesame by limiting diffused oxygen availability in soil and generating hypoxic, subsequently anoxic conditions. The present study aimed to screen the 1,006 accessions for waterlogging stress response at the seedling stage to identify the most tolerant and susceptible genotype. The investigation revealed that, 48 h of stress are detrimental and 10 days post-waterlogging impede crop survival. The screened accessions were narrowed down by 8 to detect the morphological alterations, and the morphological characteristics such as shoot height, root length, SPAD, branches per plant and relative water content r) were significantly higher in check and EC377024. Enzymatic (SOD, CAT and APX) and non-enzymatic (TFC, TPC, DPPH, FRAP, TAA, MDA and proline) antioxidant activity was notably higher in check and EC377024 and lower in IC129289. DAB and NBT assay confirmed lower damages from free radicals in EC377024 compared to IC129289. Moreover, contrasting gene expression profiling of free radicals (POD and RBOHC), carbohydrate metabolism (SuSy2 and StSy1), phosphate group gene (PSRG), and plant hormone (ERF RAP 2–7, ACC) confirmed the tolerance in EC377024 under waterlogging stress conditions. Besides, metabolomics study in EC377024 at control and 48 h of waterlogging stress indicate the significant accumulated metabolites in fatty acid (decanoate), carbohydrate, amino acid, Shikimate, MEP (5-enolpyruvoyl-shikimate-3-phosphate) Krebs cycle and Xanthophyll pathways. This comprehensive combination of morpho-physiological, biochemical, molecular and metabolomic characterizations highlight the stress responsive mechanisms between the tolerant (EC377024) and susceptible (IC129289) genotypes.

Impact of Gamma Irradiation on Biochemical and Physiological Characteristics of Black Rice

Rice (Oryza sativa L.) is a fruit caryopsis, well known for its high calorific value and presence of high antioxidant phytochemicals such as flavonoids and anthocyanins. Further exposure of crops to different doses of physical mutagens is useful to give insight into development of quality traits for plant breeding. So, the objective of the present study was to analyse the effects of gamma irradiation on black rice seeds that were exposed to different radiation doses and to evaluate the irradiation effect on physiological and biochemical characteristics of plants. Variations were observed among different doses from non-enzymatic antioxidant activities that showed the increasing flavonoids, phenolics and carotenoids accumulation from low to high doses. A high dose irradiation releases, high amount of H2O2 as compare to O2- indicating the involvement of enzymatic antioxidants as a defence mechanism. An inverse relation was shown between peroxidase and catalase enzyme and concentration of Superoxide dismutase also increased with increasing doses. To know the level of stress on cellular metabolism, total proline and malon dialdehyde accumulation was estimated and both showed positive results for increasing doses. In case of measurement of photosynthetic parameters, chlorophyll concentration increased from 50 Gy to 100 Gy and decreased from 150 Gy to 200 Gy due to peroxidation of membrane. Significant effect was not observed in the concentration of soluble sugar among various doses. Thus, the present study, was useful to isolating effective dose (50Gy, 100 Gy) that may contribute towards advancement of qualitative traits for future breeding purposes.

A study on assessing the toxic effects of ethyl paraben on rohu (Labeo rohita) using different biomarkers; hemato-biochemical assays, histology, oxidant and antioxidant activity and genotoxicity.

Parabens are being used as preservatives due to their antifungal and antimicrobial effects. They are emerging as aquatic pollutants due to their excessive use in many products. The purpose of this study was to determine the toxic effect of ethyl paraben (C9H10O3) on the hematobiochemical, histological, oxidative, and anti-oxidant enzymatic and non-enzymatic activity; the study also evaluates the potential of ethyl paraben to cause genotoxicity in Rohu Labeo rohita. A number of 15 fish with an average weight of 35.45±1.34g were placed in each group and exposed to ethyl paraben for 21 days. Three different concentrations of ethyl paraben, i.e., T1 (2000μg/L), T2 (4000 μg/L), andT3 (6000 μg/L) on which fish were exposed as compared to the control T0 (0.00 μg/L). Blood was used for hematobiochemical and comet assay. Gills, kidneys, and liver were removed for histological alterations. The results showed a significant rise in all hemato-biochemical parameters such as RBCs, WBCs, PLT count, blood sugar, albumin, globulin, and cholesterol. An increase in aspartate aminotransferase (AST) and alanine transaminase (ALT) levels directed the hepatocytic damage. Histological alterations in the liver, gills and kidneys of fish were found. Ethylparaben induces oxidative stress by suppressing antioxidant enzyme activity such as SOD, GSH, CAT and POD. Based on the comet assay, DNA damage was also observed in blood cells, resulting in genotoxicity. Findings from the present study indicate that ethyl paraben induces hemato-biochemical alterations, tissue damage, oxidative stress, and genotoxicity.

The antimicrobial activity of Hypericum perforatum L. flower extract against food pathogens and its non-enzymatic antioxidant activity

Foodborne pathogens pose a significant hazard to food safety. Most cases of foodborne illnesses are caused by bacterial pathogens that have infiltrated the food chain at some point, from farm to kitchen. According to the World Health Organization (WHO), approximately one-third of individuals in developed countries are affected by foodborne pathogens each year. Although there are studies on Hypericum perforatum L. in the literature, research in Turkey remains limited. Therefore, the aim is to contribute to the literature by studying H. perforatum samples from the Yaraş region of Muğla province in Turkey. This study specifically aims to investigate the antimicrobial activities against foodborne pathogens and the antioxidant activity of H. perforatum in Muğla. The in vitro antimicrobial activities of flower components from plants grown in Mugla were evaluated using the disc diffusion method and broth dilution test. Additionally, the extracts underwent ABTS (2,2'-azinobis-(3-ethyl benzothiazoline-6-sulfonic acid)) free-radical testing to evaluate their antioxidant activity. The extract exhibited a maximum inhibition zone of 16 mm against Staphylococcus aureus and Listeria monocytogenes. Notably, S. aureus and L. monocytogenes demonstrated the lowest sensitivity to H. perforatum methanol extract (1625 µg/mL). The methanol extract displayed moderate antioxidant activity, with a 53% ABTS radical scavenging capacity. Consequently, the extracts of H. perforatum exhibited both antimicrobial and antioxidant potential.

Response of two different Phoenix dactylifera cultivars to future climate conditions

Plants are naturally exposed to various environmental stresses that affect their growth and development. As a desert plant, Phoenix dactylifera (date palm) has developed strategies to protect itself from most abiotic stresses. However, projected climate changes and the interaction between the various abiotic stressors will have profound effects on date palm adaptation and production In the present study, the two date palm cultivars, Sultana and Zamli cultivars were exposed to elevated levels of CO2 and enhanced UVB radiation and non-enzymatic antioxidants (total phenols, α-tocopherol, reduced glutathione content) and antioxidant enzyme activities (polyphenol oxidase, peroxidase, superoxide dismutase, catalase, ascorbate peroxidase) activities were analysed. The results showed that the Sultana cultivar is tolerant to future climate conditions. However, more biotic stress and yield parameters are needed for the identification of biotic stress tolerant date palm cultivars.

Adenine methylation is very scarce in the Drosophila genome and not erased by the ten-eleven translocation dioxygenase.

N6-methyladenine (6mA) DNA modification has recently been described in metazoans, including in Drosophila, for which the erasure of this epigenetic mark has been ascribed to the ten-eleven translocation (TET) enzyme. Here, we re-evaluated 6mA presence and TET impact on the Drosophila genome. Using axenic or conventional breeding conditions, we found traces of 6mA by LC-MS/MS and no significant increase in 6mA levels in the absence of TET, suggesting that this modification is present at very low levels in the Drosophila genome but not regulated by TET. Consistent with this latter hypothesis, further molecular and genetic analyses showed that TET does not demethylate 6mA but acts essentially in an enzymatic-independent manner. Our results call for further caution concerning the role and regulation of 6mA DNA modification in metazoans and underline the importance of TET non-enzymatic activity for fly development.

Adenine methylation is very scarce in the Drosophila genome and not erased by the ten-eleven translocation dioxygenase

N6-methyladenine (6mA) DNA modification has recently been described in metazoans, including in Drosophila, for which the erasure of this epigenetic mark has been ascribed to the ten-eleven translocation (TET) enzyme. Here, we re-evaluated 6mA presence and TET impact on the Drosophila genome. Using axenic or conventional breeding conditions, we found traces of 6mA by LC-MS/MS and no significant increase in 6mA levels in the absence of TET, suggesting that this modification is present at very low levels in the Drosophila genome but not regulated by TET. Consistent with this latter hypothesis, further molecular and genetic analyses showed that TET does not demethylate 6mA but acts essentially in an enzymatic-independent manner. Our results call for further caution concerning the role and regulation of 6mA DNA modification in metazoans and underline the importance of TET non-enzymatic activity for fly development.

The influence of elevated CO2 concentrations and UVB radiation in antioxidant activity of selected Chenopodium quinoa varieties

Ecosystems have been affected by climate change. Both agriculture and environmental changes are correlated with various features since climate change is the main cause of abiotic and biotic stress, which affects crop plants. Climate change and its severe impact on plant productivity showed great intensity due to the effects of abiotic stress. In the present investigation, we selected two quinoa varieties to study the response to future climatic factors such as eCO2, enhanced UVB radiation, and UVB+eCO2 combined effects in open-top chambers in the hot climate of the UAE. The treatments were administered for 90 days in the hot UAE weather conditions and the experiment was carried out in a transparent OTC facility. The response of the studied quinoa varieties was measured by analyzing their non-enzymatic antioxidant and antioxidant enzyme activities. Our findings showed that quinoa varieties are suitable as industrial crops for their levels of antioxidants under stimulating climatic conditions because the quantity and quality of their yield have not been affected. Based on the results obtained in the present investigation, further study is warranted for screening more varieties with the addition of climate change factors such as temperature and humidity to find more tolerant varieties of quinoa suitable for future climatic conditions.

Bamboo leaf extract treatment alleviates the surface browning of fresh-cut apple by regulating membrane lipid metabolism and antioxidant properties.

The effect of bamboo leaf extract (BLE) on controlling the browning of fresh-cut apple stored at 4 °C was investigated. Browning index, H2 O2 content, O2 - production rate, malondialdehyde (MDA) contents, total phenolic content (TPC) and soluble quinone content (SQC), the activities of polyphenol oxidase (PPO), peroxidase (POD), lipoxygenase (LOX), superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX), DPPH (2,2-diphenyl-2-picryl-hydrazyl) and ABTS [2,2-azinobis(3-ethylbenzothiazoline- 6-sulfonic acid)] radical scavenging activities, and the expression of genes related to browning were all investigated. BLE effectively alleviated the surface browning of fresh-cut apple, accompanied by a reduction in SQC, LOX activity, H2 O2 , O2 - production rate and MDA accumulation. Furthermore, BLE treatment enhanced the TPC, enzymatic (SOD, CAT, APX and POD) and non-enzymatic antioxidant activities. Principal component analysis and Pearson correlation analysis found the browning inhibition by BLE is not through the reduction of phenolic substrates and PPO activity. BLE controls the browning of fresh-cut apple by increasing the antioxidant capacity to scavenge ROS, which could alleviate oxidative damage and maintain the membrane integrity. © 2023 Society of Chemical Industry.

Abstract A055: Discovery of a novel, highly potent VHL-recruiting EZH2 PROTAC degrader targeting MLL-r AML

Abstract Mutated or overexpressed Enhancer of Zeste Homolog 2 (EZH2), the catalytic subunit of the Polycomb Repressive Complex 2 (PRC2), has been implicated in numerous cancers, including breast, leukemia, and lung. Through its methyltransferase activity, EZH2 tri-methylates H3K27 to repress transcription. In addition to its enzymatic activity, recent studies have highlighted non-enzymatic oncogenic functions of EZH2 that limit the efficacy of enzymatic inhibitors. Therefore, alternative therapeutic strategies such as proteolysis targeting chimera (PROTAC) degraders that suppress both enzymatic and non-enzymatic activity have been developed. PROTACs are heterobifunctional molecules consisting of a protein of interest (POI) binder linked to an E3-ligase ligand. The manufactured proximity between the POI and the recruited E3-ligase complex initiates ubiquitination of the POI, resulting in its degradation via the 26S proteasome. EZH2 exhibits enzymatic and non-enzymatic oncogenic activity in various cancers including MLL1-rearranged acute myeloid leukemia (MLL-r AML) and triple negative breast cancer (TNBC). Here we present MS8847, a novel VHL-recruiting EZH2 PROTAC degrader. In MLL-r AML cells, MS8847 induces potent EZH2 degradation in a ubiquitin proteasome-, time- and concentration-dependent manner. Compared to the previously published EZH2-targeting PROTAC degraders (MS8815, YM281, U3i, and E7) and parent inhibitor, Tazemetostat, MS8847 displays superior EZH2 degradation and cell growth inhibition in MLL-r AML cell lines dependent on both enzymatic and non-enzymatic EZH2 activity. MS8847 also induces EZH2 degradation and cell growth inhibition in TNBC cell lines. Moreover, MS8847 has a favorable PK profile making it suitable for in vivo studies. Together, MS8847 offers an improved VHL-recruiting EZH2 PROTAC degrader with potential as an effective therapeutic agent to treat EZH2-dependent cancers. Citation Format: Julia Velez, Xufen Yu, Brandon Dale, Kwang-Su Park, H. Ümit Kaniskan, Jian Jin. Discovery of a novel, highly potent VHL-recruiting EZH2 PROTAC degrader targeting MLL-r AML [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr A055.

Beneficial Interactive Effects Provided by an Arbuscular Mycorrhizal Fungi and Yeast on the Growth of Oenothera picensis Established on Cu Mine Tailings

Phytoremediation, an environmentally friendly and sustainable approach for addressing Cu-contaminated environments, remains underutilized in mine tailings. Arbuscular mycorrhizal fungi (AMF) play a vital role in reducing Cu levels in plants through various mechanisms, including glomalin stabilization, immobilization within fungal structures, and enhancing plant tolerance to oxidative stress. Yeasts also contribute to plant growth and metal tolerance by producing phytohormones, solubilizing phosphates, generating exopolysaccharides, and facilitating AMF colonization. This study aimed to assess the impact of AMF and yeast inoculation on the growth and antioxidant response of Oenothera picensis plants growing in Cu mine tailings amended with compost. Plants were either non-inoculated (NY) or inoculated with Meyerozyma guilliermondii (MG), Rhodotorula mucilaginosa (RM), or a combination of both (MIX). Plants were also inoculated with Claroideoglomus claroideum (CC), while others remained non-AMF inoculated (NM). The results indicated significantly higher shoot biomass in the MG-NM treatment, showing a 3.4-fold increase compared to the NY-NM treatment. The MG-CC treatment exhibited the most substantial increase in root biomass, reaching 5-fold that in the NY-NM treatment. Co-inoculation of AMF and yeast influenced antioxidant activity, particularly catalase and ascorbate peroxidase. Furthermore, AMF and yeast inoculation individually led to a 2-fold decrease in total phenols in the roots. Yeast inoculation notably reduced non-enzymatic antioxidant activity in the ABTS and CUPRAC assays. Both AMF and yeast inoculation promoted the production of photosynthetic pigments, further emphasizing their importance in phytoremediation programs for mine tailings.

Silicon dioxide nanoparticles enhance plant growth, photosynthetic performance, and antioxidants defence machinery through suppressing chromium uptake in Brassica napus L.

Chromium (Cr) is a highly toxic heavy metal that is extensively released into the soil and drastically reduces plant yield. Silicon nanoparticles (Si NPs) were chosen to mitigate Cr toxicity due to their ability to interact with heavy metals and reduce their uptake. This manuscript explores the mechanisms of Cr-induced toxicity and the potential of Si NPs to mitigate Cr toxicity by regulating photosynthesis, oxidative stress, and antioxidant defence, along with the role of transcription factors and heavy metal transporter genes in rapeseed (Brassica napus L.). Rapeseed plants were grown hydroponically and subjected to hexavalent Cr stress (50 and 100 μM) in the form of K2Cr2O7 solution. Si NPs were foliar sprayed at concentrations of 50, 100 and 150 μM. The findings showed that 100 μM Si NPs under 100 μM Cr stress significantly increased the leaf Si content by 169% while reducing Cr uptake by 92% and 76% in roots and leaves, respectively. The presence of Si NPs inside the plant leaf cells was confirmed by using energy-dispersive spectroscopy, inductively coupled plasma‒mass spectrometry, and confocal laser scanning microscopy. The study's findings showed that Cr had adverse effects on plant growth, photosynthetic gas exchange attributes, leaf mesophyll ultrastructure, PSII performance and the activity of enzymatic and nonenzymatic antioxidants. However, Si NPs minimized Cr-induced toxicity by reducing total Cr accumulation and decreasing oxidative damage, as evidenced by reduced ROS production (such as H2O2 and MDA) and increased enzymatic and nonenzymatic antioxidant activities in plants. Interestingly, Si NPs under Cr stress effectively increased the NPQ, ETR and QY of PSII, indicating a robust protective response of PSII against stress. Furthermore, the enhancement of Cr tolerance facilitated by Si NPs was linked to the upregulation of genes associated with antioxidant enzymes and transcription factors, alongside the concurrent reduction in metal transporter activity.

A MUFA/carotenoid-rich oil ameliorated insulin resistance by improving inflammation and oxidative stress in obese rats

Obesity is associated with low-grade inflammation and oxidative stress, leading to insulin resistance and type II diabetes. Caryocar brasiliense pulp oil (pequi oil – PO) is rich in oleic acid and carotenoids and positively implicated in regulating inflammation and oxidative stress. This study investigated PO's antioxidant and anti-inflammatory effects in a diet-induced obesity model. Male Wistar rats were allocated into three experimental groups: Control (CD), Western Diet (WD), and Western Diet, with 27% of lard switched by PO (WDP). Metabolic, inflammatory, and oxidative stress biomarkers were evaluated after 12 weeks of diet protocols in liver and adipose tissue. WDP rats gained less body mass and epididymal fat, had less hepatic fat infiltration, and were more glucose-tolerant and insulin-sensitive than WD (p < 0.05). In the liver, the WDP group had the highest non-enzymatic antioxidant capacity, SOD and GPx activities, CAT, SOD II, and HSP72 expression compared to WD (p < 0.05). Adipose tissue IL-6 and TNF were reduced, and IL-10 was increased in WDP compared to WD (p < 0.05). Our data suggest that the partial replacement of lard by PO in a Western diet prevented visceral fat accumulation and contributed to reducing inflammation in adipose tissue and liver oxidative stress, improving obesity-related insulin resistance.

Membrane Localization and Phosphorylation of Indoleamine 2,3-Dioxygenase 2 (IDO2) in A549 Human Lung Adenocarcinoma Cells: First Steps in Exploring Its Signaling Function.

Indoleamine 2,3-dioxygenase 2 (IDO2) is a paralog of Indoleamine 2,3-dioxygenase 1 (IDO1), a tryptophan-degrading enzyme producing immunomodulatory molecules. However, the two proteins are unlikely to carry out the same functions. IDO2 shows little or no tryptophan catabolic activity and exerts contrasting immunomodulatory roles in a context-dependent manner in cancer and autoimmune diseases. The recently described potential non-enzymatic activity of IDO2 has suggested its possible involvement in alternative pathways, resulting in either pro- or anti-inflammatory effects in different models. In a previous study on non-small cell lung cancer (NSCLC) tissues, we found that IDO2 expression revealed at the plasma membrane level of tumor cells was significantly associated with poor prognosis. In this study, the A549 human cell line, basally expressing IDO2, was used as an in vitro model of human lung adenocarcinoma to gain more insights into a possible alternative function of IDO2 different from the catalytic one. In these cells, immunocytochemistry and isopycnic sucrose gradient analyses confirmed the IDO2 protein localization in the cell membrane compartment, and the immunoprecipitation of tyrosine-phosphorylated proteins revealed that kinase activities can target IDO2. The different localization from the cytosolic one and the phosphorylation state are the first indications for the signaling function of IDO2, suggesting that the IDO2 non-enzymatic role in cancer cells is worthy of deeper understanding.

Effects of Light and Oxygen Conditions on Nonenzymatic Metmyoglobin Reduction In Vitro

Previous research indicated that inherently present electron donors and carriers contribute to nonenzymatic metmyoglobin reduction. However, limited knowledge is currently available on how light and oxygen influence nonenzymatic metmyoglobin reduction. The objective of this study was to evaluate the effect of light and oxygen levels on nonenzymatic metmyoglobin reduction in vitro. Two experiments were conducted using equine metmyoglobin solution at pH 5.6 (represents typical postmortem muscle pH) with different electron donors and electron carriers in a 96-well plate. A gas blend of 80% oxygen and 20% carbon dioxide or a pure 99.9% nitrogen gas was bubbled in phosphate buffers and myoglobin solutions to create 2 oxygen levels (low oxygen [4%] and high oxygen [160%]). The desired dissolved oxygen content was measured using a NeoFox oxygen probe (atmospheric oxygen level was 20% oxygen). There were significant effects of electron donors, carriers, and light on nonenzymatic metmyoglobin reduction. Ascorbate and nicotinamide adenine dinucleotide reduced form (NADH) in the presence of methylene blue and ethylenediaminetetraacetic acid (EDTA) exhibited a greater nonenzymatic metmyoglobin reduction in light than dark. An increase in nonenzymatic metmyoglobin-reducing activity (P&amp;lt;0.0001) was observed for the combination of NADH+methylene blue+EDTA in the high-oxygen condition in comparison with the low-oxygen levels. The results indicate that light and oxygen levels increase nonenzymatic metmyoglobin reduction. Characterizing the cofactors required for nonenzymatic metmyoglobin reduction and understanding the conditions conducive to reduction enhance knowledge related to meat color changes.

Melatonin treatment maintains the quality and delays senescence of postharvest cattails (Typha latifolia L.) during cold storage.

Melatonin treatment was investigated for the sensory quality and senescence in postharvest cattails (Typha latifolia L.) during cold storage. The 0.75mM melatonin treatment reduced surface browning and delaying lignification of Cattails stored at 4°C. The results showed that melatonin treatment slowed weight loss and firmness, maintained sensory quality and reducing sugar content. Melatonin treatment reduced browning by inhibiting the increase of MDA and H2O2 contents and POD activity. Melatonin treatment maintained high non-enzymatic antioxidant components (Vitamin C and total phenolic content) and antioxidant enzyme activities (SOD, CAT, and APX), thereby alleviating the browning and senescence of postharvest cattails. These findings indicate that melatonin treatment can maintain postharvest cattails quality.

Epibrassinolide application improves Brassica juncea L. performance by augmenting gas exchange markers, stomatal behavior, cellular viability, enzymatic activities and yield attributes

Epibrassinolide (EBL) is an emerging plant growth regulator of the brassinosteroids group that has the potential to modulate various morpho-physiological processes in plants. Therefore, due to its key role in boosting plant functioning mechanisms, it is widely used in agriculture to enhance crop growth and yield. The present research work was planned to investigate the role of exogenously applied EBL on the mustard crop by assessing morphological, physiochemical, and yield features. This randomized pot experiment contains three mustard cultivars i.e., Rohini (Roh), Chutki (Chk), and Nath Sona (Nas) and various graded levels of EBL, 0 (Control), 10−8 M, 10−7 M, 10−6 M, 10−5 M, and 10−4 M. EBL was applied twice by giving first spray at 50 days after sowing (DAS) and the second at 70 DAS. Evaluation of plants was done at 90 DAS to study phenological traits, gas exchange attributes, non-enzymatic antioxidant activities, and microscopical parameters. The yield and quality features were studied at 120 DAS. The results revealed that treatment of 10−6 M EBL proved effective and increased fresh weight by 17.76 %, 19.11 %, and 19.34 %, chlorophyll content by 26.50 %, 26.59 %, and 25.86 %, net photosynthetic rate by 45.67 %, 57.88 % and 49.76 %, protein content by 66.98 %, 68.62 % and 69.47 %, proline content by 25.70 %, 24.05 % and 21.87 %, ascorbate content by 94.91 %, 89.99 % and 87.43 %, carbonic anhydrase activity by 32.43 %, 30.84 % and 29.93 %, seed yield by 44.85 %, 51.36 %, and 57 % and oil yield by 68.75 %, 72.71 % and 74.34 % in cultivars Nas, Roh, and Chk respectively over the control plants. Moreover, 10−6 M EBL supplementation significantly improved stomatal aperture width and root cell longevity. Cultivar Nas, followed by cultivars Roh and Chk, showed better responses on nearly all characters studied. The effect of EBL treatment in terms of enhancing the performance of the crop being in the order of 10−6 M > 10−7 M > 10−8 M > 10−5 M > 10−4 M. It may be concluded that among sprayed EBL levels, two sprays of 10−6 M EBL proved efficacious in improving the phenotypic, physiochemical, and yield traits of mustard cultivars.

A Novel Nutrient- and Antioxidant-Based Formulation Can Sustain Tomato Production under Full Watering and Drought Stress in Saline Soil.

As a result of the climate changes that are getting worse nowadays, drought stress (DS) is a major obstacle during crop life stages, which ultimately reduces tomato crop yields. So, there is a need to adopt modern approaches like a novel nutrient- and antioxidant-based formulation (NABF) for boosting tomato crop productivity. NABF consists of antioxidants (i.e., citric acid, salicylic acid, ascorbic acid, glutathione, and EDTA) and nutrients making it a fruitful growth stimulator against environmental stressors. As a first report, this study was scheduled to investigate the foliar application of NABF on growth and production traits, physio-biochemical attributes, water use efficiency (WUE), and nutritional, hormonal, and antioxidative status of tomato plants cultivated under full watering (100% of ETc) and DS (80 or 60% of ETc). Stressed tomato plants treated with NABF had higher DS tolerance through improved traits of photosynthetic efficiency, leaf integrity, various nutrients (i.e., copper, zinc, manganese, calcium, potassium, phosphorus, and nitrogen), and hormonal contents. These positives were a result of lower levels of oxidative stress biomarkers as a result of enhanced osmoprotectants (soluble sugars, proline, and soluble protein), and non-enzymatic and enzymatic antioxidant activities. Growth, yield, and fruit quality traits, as well as WUE, were improved. Full watering with application of 2.5 g NABF L-1 collected 121 t tomato fruits per hectare as the best treatment. Under moderate DS (80% of ETc), NABF application increased fruit yield by 10.3%, while, under severe DS (40% of ETc), the same fruit yield was obtained compared to full irrigation without NABF. Therefore, the application of 60% ETc × NABF was explored to not only give a similar yield with higher quality compared to 100% ETc without NABF as well as increase WUE.

Zinc sulfate biofortification enhances physio-biochemical attributes and oxidative stress tolerance in rice varieties grown in zinc deficient alkaline soil

Zinc (Zn) is a crucial trace mineral with diverse roles in plants; its deficiency in edible plant parts results in micronutrient malnutrition, leading to stunted growth. Zinc deficiency in the soil is a significant factor leading to poor rice quality. This research aimed to reveal the impact of Zn biofortification on rice productivity and to introduce rice cultivars with enriched nutrients. The effects of various zinc sulfate (ZnSO4) rates viz. 100, 200, 300, 400 and 500 mM (designated as T1, T2, T3, T4 and T5, respectively) on the germination process, chlorophyll pigments, biochemical activities, and the mitigation of oxidative damage in four different rice (Oryza sativa L.) cultivars (KSK-133, Basmati-198, Basmati-515, and PK-386) grown in alkaline Zn-deficient soil were evaluated. A control without Zn application (T0) was kept for comparison. Results demonstrated that Zn treatments significantly affected the germination rates, vegetative growth, photosynthetic attributes, and enzymatic and non-enzymatic activities of all tested cultivars. Zn application significantly ameliorated the oxidative stress by increasing antioxidant enzyme activities such as catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), ascorbate peroxidase (APX), 2,2-diphenyl-1-picrylhydrazyl (DPPH), glutathione peroxidase, and non-enzymatic compounds (such as flavonoids, proline, phenolics, reducing sugar and non-reducing sugar, total carbohydrates, and free amino acid) in all tested cultivars. Among the application rates, ZnSO4 application at 400 mM depicted the highest values of the above-mentioned traits. Furthermore, recorded data also revealed that ZnSO4 had a significant impact on flavonoids, total carbohydrates, and phenolic contents where its application at 400 mM depicted significantly higher values than other treatments. Among the tested cultivars, Basmati-198 exhibited the highest values of flavonoids, total carbohydrates, and phenolic contents showing an increase of 134.53%, 103.57%, and 265.34%, respectively, over the average of other cultivars. In sum, ZnSO4 application at 400 mM significantly improved rice performance under alkaline conditions whereas its application at 500 mM onsets toxic effect on all tested cultivars. However, to gain a comprehensive understanding of the underlying mechanisms, further research is needed to conduct long-term field studies at the molecular level.