Search results for "Antioxidant"
showing 10 items of 1553 documents
The In Vitro Interaction of 12-Oxophytodienoic Acid and Related Conjugated Carbonyl Compounds with Thiol Antioxidants
2021
α,β-unsaturated carbonyls interfere with numerous plant physiological processes. One mechanism of action is their reactivity toward thiols of metabolites like cysteine and glutathione (GSH). This work aimed at better understanding these interactions. Both 12-oxophytodienoic acid (12-OPDA) and abscisic acid (ABA) conjugated with cysteine. It was found that the reactivity of α,β-unsaturated carbonyls with GSH followed the sequence trans-2-hexenal <
Antioxidant Phenolic Compounds in Salvia officinalis L. and Salvia sclarea L.
2018
Abstract The differences in the chemical composition of the phenolic compounds of Salvia officinalis versus Salvia sclarea growing in different habitats, were studied. First, the optimal solvent - methanol - for ultrasonic extraction of phenolic compounds from these plants was chosen experimentally. Total phenolic content and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were determined spectrophotometrically. Total phenolic content was in the range of 63.9 to 134.4 mg GAE/g of plant depending on the studied species. The highest antiradical activity was displayed by the methanol fractions of S. sclarea varieties (83 and 67%). HPLC-DAD analysis of extracts was done in order to identify the pre…
Wild and cultivated mushrooms as a model of sustainable development
2013
The natural resources are currently overexploited and since 1992 the Conference of Rio de Janeiro has focused on sustainable development to safeguard our planet for future generations. The Fungi kingdom includes producers of goods and services for ecosystems and organisms widely used in the food industry. Besides, macrofungi are recognized as nontimber forest products and could be utilized as agents of environmental management through weed biocontrol and environmental improvement. Moreover, the cultivation of fungi, in particular truffles, can provide an important income in agroecosystems, especially in marginal areas, along with the development of new technologies to produce novel products…
The antioxidant 2,3‐dichloro,5,8‐dihydroxy,1,4‐naphthoquinone inhibits acetyl‐cholinesterase activity and amyloid β 42 aggregation: A dual target the…
2020
Alzheimer's disease is characterized by amyloid β aggregation and cholinergic neurodegeneration. In the present study, pure DDN (2,3-dichloro-5,8-dihydroxy-1,4-naphthoquinone) was examined, for the first time, for its dual potential as inhibitor of acetylcholinesterase (AChE) and Aβ42 aggregation. Such investigation was encouraged by the in vitro high antioxidant potential of DDN. Indeed, it revealed interesting antioxidant activity with IC50 values of 9.8 and 4.3 µM for ABTS and reducing power, respectively. The ability of DDN to counteract Aβ42 aggregation was evaluated by thioflavine-T assay. Strong inhibition of Aβ42 aggregation of more than 90% at 25 µM was measured. Moreover, results …
High‐power ultrasound altered the polyphenolic content and antioxidant capacity in cloudy apple juice during storage
2019
The aim was to investigate the influence of high‐power ultrasound treatment (HPU) on polyphenolic stability and antioxidant capacity in cloudy apple juice during 7 days of storage at 4°C. HPU (100 W, 30 kHz frequency) was operated at: (i) amplitude 40 versus 80%, (ii) the probe diameter 7 versus 10 mm, and (iii) treatment time of 3, 6, and 9 min. Total phenols (TP), total flavan‐3‐ols (TFL), and in vitro antioxidant capacity (DPPH and FRAP) were determined spectrophotometrically. Findings revealed that HPU significantly decreased TP, TFL, and antioxidant capacity in the samples. However, results indicated that examined sonication parameters, represented as the probe diameter and treatment t…
Micro and nano-encapsulation of vegetable and essential oils to develop functional food products with improved nutritional profiles
2020
Abstract Background A growing awareness regarding the benefits of consumption of functional foods has resulted in the development of new food products through using bioactive compounds. Vegetable-essential oils (V-EOs) are among the most popular ingredients used for the enrichment of different food products to boost their functional properties. However, these oils are sensitive to harsh conditions such as oxidation stress and high temperatures. Recently, different micro/nanoencapsulation systems have been applied to produce suitable carriers for V-EOs to be incorporated into food formulations, which can overcome the limitation of their pure application in foods. Scope and approach Controlle…
Anti-Bacterial Activity and Online HPLC-DPPH Based Antiradical Kinetics of Medicinal Plant Extracts of High Relevance for Cosmetics Production
2018
The present study provides an assessment of extracts of six medicinal plants for their applicability in cosmetic formulations aimed at anti-UV protection and anti-acne treatment. Ethanol extracts of Chelidonium majus L., Myrtus communis L., Hamamelis virginiana L., Juniperus communis L., Alchemilla vulgaris and Ilex paraguariensis are analysed for the phytochemical content, antimicrobial activity, antiradical activity and antiradical kinetics. The phytochemical composition of the plants is investigated by LC-MS analysis and the most active antioxidants in plant extracts are determined by online HPLC-DPPH assay. The kinetic parameters of the antiradical reaction are determined both for the s…
The Influence of Film and Storage on the Phenolic and Antioxidant Properties of Red Raspberries (Rubus idaeus L.) cv. Erika
2019
In this paper, the effect of the packaging material and storage method on red raspberries produced at Reggio Calabria (Italy) was studied. For this purpose, the fruits were stored immediately after harvest in different conditions: in the fridge at 1 °
Effect of methylparaben in Artemia franciscana.
2017
In this study, the toxicity of methylparaben (MeP) an emerging contaminant, was analysed in the sexual species Artemia franciscana, due to its presence in coastal areas and marine saltworks in the Mediterranean region. The acute toxicity (24 h-LC50) of MeP in nauplii was tested and its chronic effect (9 days) evaluated by measuring survival and growth under two sublethal concentrations (0.0085 and 0.017 mg/L). Also, the effect on several key enzymes involved in: antioxidant defences (catalase (CAT) and gluthathion-S-transferase (GST)), neural activity (cholinesterase (ChE)) and xenobiotic biotransformation (carboxylesterase (CbE), was assessed after 48 h under sublethal exposure. The result…
Effect of hydrogen peroxide on the dehydrogenase and quinone-reductase activity of irradiated Lactobacillus plantarum cells
2020
Abstract The resistance of lactobacilli to oxidative stress is of great importance for their applicability as probiotics. This study aimed to evaluate the response of Lactobacillus plantarum strain ATCC® 14917™, grown in either de Man, Rogosa, and Sharpe agar (MRS medium) or tryptic soy broth (TSB medium), to 1–2 mM H2O2 after the exposure to different doses of ionising radiation. Two bacterial extracellular enzyme groups, dehydrogenases (DHAs) and quinone reductases (QRs), served as the criteria of viability and antioxidant activity, respectively. The irradiated L. plantarum culture grown in TSB showed increased QR activity at irradiation doses of 2–50 Gy, with the maximum activity at 10 G…