Changes in Antioxidant Defence System in Durum Wheat under Hyperosmotic Stress: A Concise Overview

Durum wheat is one of the most commonly cultivated species in the world and represents a key commodity for many areas worldwide, as its grain is used for production of many foods, such as pasta, bread, couscous, and bourghul. Durum wheat grain has a relevant role in the human diet, providing carbohydrates, proteins, lipids, fibres, vitamins, and minerals, as well as highly valued bioactive compounds contributing to a healthy diet. Durum wheat is largely cultivated in the Mediterranean basin, where it is mainly grown under rain-fed conditions, thus currently undergoing drought stress, as well as soil salinity, which can hamper yield potential and influence the qualitative characteristics of grain. When plants suffer drought and/or salinity stress, a condition known as hyperosmotic stress is established at cellular level. This leads to the accumulation of ROS thus generating in turn an oxidative stress condition, which can ultimately result in the impairment of cellular integrity and functionality. To counteract oxidative damage due to excessive ROS production under stress, plants have evolved a complex array of both enzymatic and non-enzymatic antioxidant mechanisms, working jointly and synergically for maintenance of ROS homeostasis. Enhancement of antioxidant defence system has been demonstrated as an adaptive mechanism associated to an increased tolerance to hyperosmotic stress. In the light of these considerations, this review provides a concise overview on recent advancements regarding the role of the ascorbate-glutathione cycle and the main antioxidant enzymes (superoxide dismutase, catalase, and peroxidases) in durum wheat response to drought and salt stresses that are expected to become more and more frequent due to the ongoing climate changes.

Impaired Antioxidant Defence Status Is Associated With Metabolic-Inflammatory Risk Factors in Preterm Children With Extrauterine Growth Restriction: The BIORICA Cohort Study

Introduction: An impaired antioxidant status has been described during foetal growth restriction (FGR). Similarly, the antioxidant defence system can be compromised in preterm children with extrauterine growth restriction (EUGR). The aim of this prospective study was to evaluate the antioxidant status in prepubertal children with a history of prematurity without FGR, with and without EUGR, compared to a healthy group.Methods: In total, 211 children were recruited and classified into three groups: 38 with a history of prematurity and EUGR; 50 with a history of prematurity and adequate extrauterine growth (AEUG); and 123 control children born at term. Catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR) activities were assessed in lysed erythrocytes with spectrophotometric methods. Plasma levels of the antioxidants α-tocopherol, retinol and β-carotene were determined through solvent extraction and ultra-high-pressure liquid chromatography coupled to mass spectrometry.Results: Children with the antecedent of EUGR and prematurity had lower CAT activity than the other two groups and lower GPx activity than the control children. Lower SOD, GPx and GR activities were observed in the AEUG group compared to the controls. However, higher concentrations of α-tocopherol and β-carotene were found in the EUGR group compared to the other groups; retinol levels were also higher in EUGR than in AEUG children. In EUGR and AEUG children, enzymatic antioxidant activities and plasma antioxidants were associated with metabolic syndrome components and pro-inflammatory biomarkers.Conclusions: This study reveals, for the first time, that the EUGR condition and prematurity appear to be linked to an impairment of the antioxidant defence status, which might condition an increased risk of adverse metabolic outcomes later in life.

Reduction of chilling injury of ‘Washington’ navel orange fruits by melatonin treatments during cold storage

Cold storage is used to improve the efficiency of storage and handling of orange fruits, but the fruits are exposed to chilling injury (CI). Antioxidant enzymes are part of the antioxidant defence system against CI of ‘Washington’ oranges during cold storage, which controls storage/handling efficiency. In this study, melatonin (ME) was used on fruits to reduce cold damage. To assess the action of ME influences; fruits were picked from the tree at the commercial maturity stage and divided into two groups that were uniform in size and colour. Then, they were immersed in ME solution at 0 mmol, 10 mmol, 100 mmol or 1,000 mmol for 20 min at 20 ± 1 °C. The treated fruits were stored at 4 ± 1 °C and 95 ± 1% RH for 4 weeks during 2019 and 2020 seasons. The physical and chemical characteristics of the stored fruits were measured every week up to the end of the storage period. Results indicated that immersing fruits in 1,000 μM ME minimised the CI-index and the water loss%, while preserving the orange peel colour (h°) during cold storage. On the other hand, the same treatment caused slight changes in soluble solid content (SSC%), maintained ascorbic acid (AA) content and the stability of total acidity (TA%), enhanced the antioxidant enzymes activities (AEAs) such as ascorbate peroxidase (APX), catalase (CAT), and superoxidase dismutase (SOD) and also reduced the rate of malondialdehyde (MDA) and ion leakage (IL) during cold storage. Moreover, it minimised hydrogen peroxide (H2O2) and superoxide anion (O2 •−) production and caused pronounced results to be exhibited in antioxidant capacity. Overall, the 1,000 μM ME treatment for orange fruits afforded more tolerance against cold storage stress.

Formulation and Evaluation of Kaempferol Loaded Nanoparticles against Experimentally Induced Hepatocellular Carcinoma: In Vitro and In Vivo Studies

The present study was designed to prepare Kaempferol loaded nanoparticles (KFP-Np) and evaluate hepatoprotective and antioxidant effects in hepatocellular carcinoma models. KFP was encapsulated with hydroxypropyl methylcellulose acetate succinate (HPMC-AS) and Kollicoat MAE 30 DP polymers to prepare nanoparticles (Nps) by quasi-emulsion solvent diffusion technique (QESD). The prepared Nps were evaluated for different pharmaceutical characterization to select the optimum composition for the in vivo assessment. An animal model of cadmium chloride (CdCl2)-induced hepatocellular carcinoma in Male Sprague Dawley rats was used in vivo to test the antioxidant and hepatoprotective capacity of free and encapsulated KFP. The prepared Npsshowed nanometric size, low PDI, high drug load as well as encapsulation with a better drug release profile. There was a significant decrease in the increased serum levels of alanine transaminase (ALT), total bilirubin (TBiL), and aspartate transaminase (AST), and the lipid peroxidation’s (MDA) level was attenuated, and levels of markers of the cell antioxidant defence system were restored including Glutathione S-transferase (GST), glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) via oral pre-treatment with KFP-Np (50 mg/kg b.w. (body weight), 6 weeks). KFP-Np significantly declines an mRNA expression of interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-alpha (TNF-α) as well as decreased nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) protein expression. It also upregulated the mRNA expression and protein expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). While comparing the protective effects of KFP encapsulated in Kollicoat MAE 30 DP and HPMC-AS, Nps was found to be betterthan free KFP. Insummary, result indicate that encapsulation of KFP in NPs provides a potential platform for oxidative stress induce liver injury.

Potential role of L-glutamic acid in mitigating cadmium toxicity in lentil (Lens culinaris Medik.) through modulating the antioxidant defence system and nutrient homeostasis

Using phosphate fertilizers and wastewater as a source of irrigation and residuals from industries have considerably increased the level of cadmium (Cd) in soil which severely reduced the growth and yield of crop. L-glutamic acid (L-Glu), an amino acid, plays key roles in plant stress tolerance. Hence, the current study was conducted to determine the potential role of L-Glu pre-treatment in alleviating Cd-induced toxicity in lentil (Lens culinaris Medik.). Lentil seedlings were exposed to two doses of Cd (1 and 2 mM CdCl2) with or without 10 mM L-Glu pre-treatment. The results suggested that a high dose of Cd negatively affected the shoot dry weight, root dry weight, and photosynthetic pigments (chlorophylls and carotenoids). Furthermore, Cd stress induced severe oxidative damage, a reduction in catalase (CAT) activity and ascorbate (AsA) content, and accumulation of Cd in both the roots and shoots. Adding L-Glu protected the photosynthetic pigments of the lentil seedlings and thus improved the growth of the seedlings. In addition, L-Glu pre-treatment enhanced the ascorbate (AsA) content; increased the activity of enzymes such as catalase, ascorbate peroxidase, monodehydroascorbate reductase, and glutathione peroxidase. L-Glu was also reduced Cd uptake and translocation, which in turn alleviated the oxidative damage in the Cd-stressed seedlings indicated the potential role of this chemical. Results suggest that pre-treatment with L-Glu reduces Cd toxicity in lentil seedlings by inhibiting Cd accumulation and by reducing oxidative damage.

Analysis of Secondary Metabolites from Infloroscense Extract of Achyranthus Aspera

The qualitative study of extract of AchyranthesAspera influoroscence shows the presence of different secondary metabolites. The study of active component of influoroscence of Achyranthesaspera was extracted . Plant extract contains several secondary metabolites .The extract was used for different phytochemical test. Test was performed using extract prepared by soxhlet extraction method. This plant have anti oxidative agent ,free radicals , phytoconstituents , and carcinogen detoxification and antioxidant defence system. Keywords: secondary metabolites, phytochemical test, antiallergic activity, antiperoxidative agent ,detoxification etc.