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Power ultrasound is applied in food technology to intensify extraction processes, due to the phenomena ultrasonic energy induces in the medium, enhancing mass transfer. The purpose of this work was the acoustic characterization of four transducers of different geometries and the evaluation of their performance in the ultrasonically assisted supercritical fluid extraction of antioxidants from oregano. The transducers differed in the amount of energy transmitted into the medium. Designs varied from the base model (T1), a larger cylindrical headmass (T2), a stepped circular section sonotrode (T3) and a multiplate configuration (T4). The highest nominal power density provided according to the calorimetric method was for T4 (151.6 ± 7.1 W/L). The T2 produced a more uniform acoustic field and a higher acoustic pressure (150.6 ± 20.5 kPa). Both parameters had an impact on total phenolics and antioxidants extraction with CO 2 under supercritical conditions (35 MPa, 35 °C, 2.3% ethanol as co-solvent). T4 and T2 were equally efficient (4.0 ± 0.2 and 4.2 ± 0.2 mg GA/g) for phenolic extraction, and with respect to antioxidant capacity, the best performance was that of T4 (26.4 ± 1.1 μmol TE/g). Of the antioxidant compounds extracted, flavones and flavanones were identified. Therefore, transducer geometry influenced the amount and distribution of energy transmitted into the medium, thus determining the efficiency of the extraction process. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Hymenocallis littoralis (Jacq.) Salisb . has been referred as beach spider lily and commonly known for its rich phytochemical diversity. Phytochemicals such as alkaloids, volatile constituents, phenols, flavonoids, flavonols extracted from different parts of these plants like bulbs, flowers, leaf, stem and root had been used in folk medicines from ancient times because of their excellent antimicrobial and antioxidant properties. The leaf and bulb extract of H. littoralis plant was traditionally used for wound healing. Alkaloids extracted from bulb of this plant possess anti-viral, anti-neoplastic and cytotoxic properties. However, these phytochemicals have also shown antibiofilm activity, which is considered as one of the important factor accountable for the drug resistance in microorganisms. Thus, the investigation of medicinal properties of H. littoralis could be useful to control biofilm producing pathogens. Aim of the study Explore antimicrobial, antibiofilm and antioxidant potentials of H. littoralis against pathogenic microorganisms using experimental and computational biology approach. Materials and methods Phytochemical extraction from dried powder of H. littoralis leaves was done by solvent extraction using methanol. Antimicrobial and antibiofilm activities of leaves extract were carried out using agar well diffusion method, growth curve, minimum inhibitory concentration (MIC) and Scanning Electron Microscopy (SEM). Liquid Chromatography and Mass Spectroscopy (LCMS) technique was used for the identification of phytochemicals. Molecular docking studies of antibiofilm agents with adhesin proteins were performed using Autodock 4.2. Antioxidant activity of extract was carried out by FRAP assay. The noxious effect of extract was investigated by histological studies on rat skin. Results The preliminary phytochemical analysis of methanolic leaves extract revealed the presence of alkaloids, flavonoids, terpenoid, glycosides, terpene, terpenoids and phenolics. The various phytochemicals such as Apigenin 7-(4′′, 6′′ diacetylalloside)-4′- alloside, Catechin 7-O- apiofuranoside, Emodic acid, Epicatechin 3-O- β-D-glucopyranoside, 4 – Methylesculetin, Methylisoeugenol, Quercetin 5,7,3′,4′-tetramethyl ether 3-rutinoside, 4 – Methylumbelliferyl β-D- glucuronide were extracted, characterized and recognized from the leaves extract of H. littoralis. The identification of these phytochemicals was performed using LC-MS. The antimicrobial property of H. littoralis leaf extract was investigated against different pathogenic microorganisms. Out of these tested microorganisms, promising antibiofilm and antimicrobial activities were confirmed against S. aureus NCIM 2654 and C. albicans NCIM 3466 by using growth curve and SEM analysis. MIC of this leaf extract was identified as 45 µg/ml and 70 µg/ml for S. aureus NCIM 2654 and C. albicans NCIM 3466 respectively. The leaves extract also showed good antioxidant activity due to presence of phenols and flavonoids. Molecular docking of these identified antibiofilm components interacts with the active site residues of adhesin proteins, Sortase A and Als3 from S. aureus and C. albicans respectively. Histological studies of extracted phytochemicals revealed non-noxious effects on rat skin. Conclusion Thus, the present study revealed that the leaves extract of H. littoralis contains various phytochemicals having good extent of antimicrobial, antibiofilm and antioxidant properties. The in-vitro and in-silico results would be useful to design new lead compounds against biofilm producing pathogenic microorganisms. [ABSTRACT FROM AUTHOR]

Hexavalent chromium [Cr(VI)] is the most toxic and potent form of chromium and induces multiple organ damage in humans and experimental animals. Oxidative stress has been implicated in the toxicity of Cr(VI). We have examined the potential role of 3,4-dihydroxybenzaldehyde (DHB), a plant polyphenolic antioxidant, in protecting human erythrocytes and lymphocytes from Cr(VI)-induced cytotoxicity and genotoxicity. Erythrocytes were treated with potassium dichromate, a Cr(VI) compound, in presence and absence of DHB. Incubation of erythrocytes with Cr(VI) enhanced the generation of reactive oxygen and nitrogen species, increased lipid and protein oxidation, methemoglobin levels, and lowered antioxidant power of cells. However, prior treatment of erythrocytes with DHB, resulted in a significant DHB dose-dependent decrease in reactive oxygen and nitrogen species levels and restoration of oxidative stress parameters. DHB also improved the antioxidant power of erythrocytes and restored the activities of major antioxidant, metabolic and membrane bound enzymes. Electron microscopic studies images DHB prevented Cr(VI)-induced morphological changes in erythrocytes. The single cell gel electrophoresis assay showed that DHB mitigated Cr(VI)-induced DNA damage in lymphocytes. These results clearly show that DHB protects human blood cells from Cr(VI)-induced oxidative damage and can be potentially used in reducing the toxic effects of this metal ion. [ABSTRACT FROM AUTHOR]

Aluminum (Al) is a neurotoxic associated with a number of chronic human diseases. We investigated the effects of Al exposure at doses similar to human dietary levels and at a high level exposure to Al on the peripheral nervous system. Wistar male rats were divided into two major groups and received orally: 1) First group – Low level - rats were subdivided and treated for 60 days: a) Control – received ultrapure water; b) AlCl 3 – received Al at 8.3 mg/kg body weight (bw) for 60 days; and 2) Second group – High level - rats were subdivided and treated for 42 days: C) Control – received ultrapure water through oral gavage; d) AlCl 3 – received Al at 100 mg/kg bw for 42 days. Von Frey hair test, plantar test, the presence of catalepsy and the spontaneous motor activity were investigated. Reactive oxygen species, lipid peroxidation and total antioxidant capacity, immunohistochemistry to investigate the nerve inflammation and, the specific presence of Al in the sciatic nerve fibers were investigated. Al exposure at a representative human dietary level promotes the development of mechanical allodynia, catalepsy, increased inflammation in the sciatic nerve, systemic oxidative stress and, is able to be retained in the sciatic nerve. The effects of low-dose Al were similar to those found in rats exposed to Al at a dose much higher (100 mg/kg). Our findings suggest that Al may be considered toxic for the peripheral nervous system, thus inducing peripheral dysfunction. [ABSTRACT FROM AUTHOR]

Background& Aims: Blood transfusion therapy is lifesaving for individuals with β-thalassemia major (β-TM). Iron burden following blood transfusion is the main cause of oxidative stress (OS) and organ dysfunction in these patients. The aim of this study was to evaluate the effects of silymarin on serum antioxidant and oxidative status in patients with β-TM.Methods: A crossover, randomized controlled trial was performed on 82 thalassemia patients. In two periods of 12 weeks, patients received 420mg silymarin (divided into three equal 140-mg daily doses) and placebo. The washout period between the two phases was two weeks. Serum malondialdehyde (MDA), protein carbonyl (CO), total antioxidant capacity (TAC), and reduced glutathione (GSH) were measured before and after both periods.Results: Sixty-nine patients completed the study. Mean serum MDA and protein CO significantly decreased in all patients with β-TM after three months of treatment with silymarin. At the end of the study, serum MDA decreased from 20.36±20.11 to 4.79±4.71μmol/l (compared to 17.81±16.05μmol/l after administration of placebo), and protein CO dropped from 0.31±0.28 to 0.11±0.09mM/l (compared to 0.24±0.17mM/l with placebo). Additional laboratory parameters (such as serum TAC and plasma GSH) were also significantly elevated after therapy with silymarin. At the end of the study, serum TAC increased in all patients from 620.7±202.64 to 971.83±328.16μmol FeSO4/l (compared to 672.22±206.88μmol FeSO4/l with placebo), and GSH increased from 46.16±41.68 to 195.35±210.98nM/l (compared to 58.52±48.95nM/l with placebo). The treatment effect of silymarin was measured using a mixed-effects model of variance analysis for changes in MDA, protein CO, TAC, and GSH, with significant effects being demonstrated for each laboratory parameter (P<0.001, P=0.002, P<0.001, and P<0.001, respectively).Conclusions: Silymarin was effective in decreasing serum OS and enhancing serum antioxidant capability in patients with β-thalassemia major. Silymarin given as an adjuvant therapy to standard iron chelators may provide an improvement in the OS measurements obtained in these patients, with accompanying benefit. [ABSTRACT FROM AUTHOR]

The present study has been conducted to explore a novel strategy to modulate the unfavourable effects of indomethacin by Phyllanthus niruri protein (PNP) and the underlying mechanism PNP exploits for the amelioration of that pathophysiology. In hepatocytes, indomethacin enhanced reactive oxygen species (ROS), reduced intracellular antioxidant capacity, up regulated mitogen activated protein kinase (MAPKs), disrupted mitochondrial membrane potential, activated apoptotic pathways and there by reduced the viability of the hepatocytes. Simultaneous treatment with PNP modulated these detrimental actions of the drug and retained cell viability. Similarly, in mice, indomethacin elevated serum marker enzymes (e.g. Alanine Transaminase), decreased antioxidant enzyme activities, elevated oxidations of lipids and proteins, increased intracellular calcium overload mediated endoplasmic reticular stress (ER stress) pathways, up regulated the pro-inflammatory cytokines and there by leading to the mitochondrial dependent caspase-3 activation and poly-ADP ribose polymerase (PARP) cleavage. Moreover investigation of these inherent molecular pathways exhibited that these alterations are associated with up regulation of MAPKs, inducible nitric oxide synthase (iNOS), heme oxygenase-1 and down regulation of survival proteins. However, PNP suppressed those apoptotic indices as evidenced from histopathological studies and DNA fragmentation analysis. Combining, results suggest that PNP could possibly provide a protection against indomethacin-induced hepatic pathophysiology. [ABSTRACT FROM AUTHOR]

Pharmaceutically active compounds (PhACs) have been recently shown to exert phytotoxic effects. The present study explores the uptake, systemic translocation, and abiotic stress responses and detoxification mechanisms induced by the exposure of alfalfa plants grown in sand under greenhouse conditions to four common, individually applied PhACs (10 μg L − 1 ) (diclofenac, sulfamethoxazole, trimethoprim, 17a-ethinylestradiol) and their mixture. Stress physiology markers (lipid peroxidation, proline, H 2 O 2 and NO content, antioxidant activity assays) and gene expression levels of key plant detoxification components (including glutathione S -transferases, GST7 , GST17 ; superoxide dismutases, CuZnSOD , FeSOD ; proton pump, H + -ATP , and cytochrome c oxidase, CytcOx ), were evaluated. PhACs were detected in significantly higher concentrations in roots compared with leaves. Stress related effects, manifested via membrane lipid peroxidation and oxidative burst, were local (roots) rather than systemic (leaves), and exacerbated when the tested PhACs were applied in mixture. Systemic accumulation of H 2 O 2 in leaves suggests its involvement in signal transduction and detoxification responses. Increased antioxidant enzymatic activities, as well as upregulated transcript levels of GST7 , GST17 , H + -ATPase and CytcOx , propose their role in the detoxification of the selected PhACs in plants. The current findings provide novel biochemical and molecular evidence highlighting the studied PhACs as an emerging abiotic stress factor, and point the need for further research on wastewater flows under natural agricultural environments. [ABSTRACT FROM AUTHOR]

We quantified the levels of polyphenols, carotenoids and polysaccharides in fruits of the eight Chinese native goji genotypes, antioxidant activities of these fruit extracts were also evaluated by DPPH, ABTS and FRAP methods. Quercetin-rhamno-di-hexoside (435–1065 μg/g) and quercetin-3-O-rutinoside (159–629 μg/g) were found to be the predominant flavonoids. Chlorogenic acid was the most abundant phenolic acid (113–526 μg/g), while zeaxanthin (17–9306 μg/g) was the major carotenoid. The total antioxidant activities (TAA) of the berry extracts were significantly correlated with the total polysaccharide and phenolic contents, but not with total carotenoid (TC) levels. Overall, fruits of the Ningxia goji ( Lycium barbarum L.) genotypes, DM (Damaye), NJ1 (Ningji No.1), BH (Baihua) and NH (Ningxiahuangguo) were not only rich in polyphenols, carotenoids and polysaccharides, but had significantly higher TAA than those of the other genotypes, suggesting that they represent an excellent source of antioxidants for human nutrition. [ABSTRACT FROM AUTHOR]

Polyphenols are the predominant ingredients in apple seeds. However, few data are available on the phenolic profile or antioxidant activity in apple seeds in previous researches. In this study, low-molecular-weight phenolic compounds and antioxidant activity in seeds, peels, and flesh of seven apple cultivars grown in northwest China were measured and analyzed using HPLC and FRAP, DPPH, ABTS assays, respectively. HPLC analysis revealed phloridzin as the dominant phenolic compound in the seeds with its contents being 240.45–864.42 mg/100 gDW. Total phenolic content (TPC) measured by the Folin–Ciocalteu assay in apple seed extracts of seven cultivars ranged from 5.74 (Golden Delicious) to 17.44 (Honeycrisp) mgGAE/gDW. Apple seeds showed higher antioxidant activity than peels or flesh; antioxidant activity in seeds varied from 57.59 to 397.70 μM Trolox equivalents (TE)/g FW for FRAP, from 37.56 to 64.31 μM TE/g FW for DPPH, and from 220.52 to 708.02 μM TE/g FW for ABTS. TPC in apple seeds was significantly correlated with all three assays. Principal component analysis (PCA) indicated that Honeycrisp was characterized with high contents of total polyphenols and phloridzin. Our findings suggest that phenolic extracts from apple seeds have good commercial potential as a promising antioxidant for use in food or cosmetics. [ABSTRACT FROM AUTHOR]

Macromolecular antioxidants or non-extractable polyphenols are an emerging and ignored fraction of dietary antioxidants that present differential structural and physiological features as compared with the well-known extractable polyphenols. In this study, the macromolecular antioxidant content and profile were determined by the first time for the 24 most consumed fruit and vegetables in four European countries (France, Germany, The Netherlands and Spain). Results showed that macromolecular antioxidants, made up of hydolysable polyphenols and polymeric proanthocyanidins, are major contributors (mean value 57%) to the total polyphenol content of fruit and vegetables. Macromolecular antioxidant intake from fruit and vegetable determined in the four countries selected was about 200 mg. Spain had the highest daily per capita macromolecular antioxidant intake from fruit, while The Netherlands had the highest intake derived from vegetables. Future studies of plant food macromolecular antioxidant analysis and of dietary intakes in different populations are needed to elucidate the contribution of these macromolecular antioxidants to the health effects associated with fruit and vegetable consumption, and with dietary antioxidant intake. [ABSTRACT FROM AUTHOR]

Ascorbic acid (AsA) and melatonin (Mel) are known molecules participating in stress resistance, however, their combined role in counteracting the impact of salinity in plants is still unknown. In this work the effect of exogenous application of 0.50 mΜ AsA, 1 μΜ Mel and their combination (AsA + Mel) on various stress responses in leaves and roots of Citrus aurantium L. seedlings grown under 100 mΜ NaCl for 30 days was investigated. Application of AsA, Mel or AsA + Mel to saline solution decreased NaCl-induced electrolyte leakage and lipid peroxidation and prevented NaCl-associated toxicity symptoms and pigments degradation. Also, leaves exposed to combined AsA + Mel treatment displayed lower Cl − accumulation. Treatments with AsA and/or Mel modulated differently carbohydrates, proline, phenols, glutathione and the total antioxidant power of tissues as well as the activities of SOD, APX, POD, GR and PPO compared to NaCl alone treatment. Exposure of leaves and roots to chemical treatments and especially to combined AsA and Mel application was able to regulate CaMIPS , CaSLAH1 and CaMYB73 expression, indicating that sugar metabolism, ion homeostasis and transcription regulation were triggered by AsA and Mel. These results provide evidence that the activation of the metabolic pathways associated with combined AsA and Mel application are linked with salt adaptation in citrus plants. [ABSTRACT FROM AUTHOR]

Green asparagus spears are a good source of phytochemical antioxidants which may positively affect human health. Cooking conditions should be optimized for retention and availability of beneficial compounds in order to benefit consumers. The objectives of this study were to identify the cooking method(s) and duration(s) that allow the greatest retention of rutin and glutathione and antioxidant activity. Spears were baked, boiled, pan-fried, grilled, microwaved, and steamed, each for three durations, and compared to raw spears. Rutin was heat-stable for all methods and durations, but boiling leached up to 22% of that found in uncooked spears. Glutathione concentrations decreased with increasing cooking duration for methods using dry heat: baking, pan-frying, and grilling. Antioxidant activity increased or remained unchanged after cooking regardless of method or duration. The results suggest that green asparagus is moderately resistant to phytochemical losses during cooking, though minimizing duration may optimize the benefits from consumption. [ABSTRACT FROM AUTHOR]

Cornelian cherry ( Cornus mas L.) fruits have been used in traditional cuisine and in folk medicine in various countries. This study was conducted to evaluate the constituents and impact of cornelian cherry ( C. mas L.) fruits lyophilisate on lipid levels, PPARα protein expression, atheromatous changes in the aorta, oxido-redox state, and proinflammatory cytokines in hypercholesterolemic rabbits. The HPLC–MS method was used for determining active constituents in cornelian cherry. In a subsequent in vivo study the protective effect of the cornelian cherry on diet-induced hyperlipidemia was studied using a rabbit model fed 1% cholesterol. Cornelian cherry (100 mg/kg b.w.) or simvastatin (5 mg/kg b.w.) were administered orally for 60 days. Two iridoids – loganic acid and cornuside – and five anthocyanins were identified as the main constituents of the cornelian cherry. The administering of the cornelian cherry led to a 44% significant decrease in serum triglyceride levels, as well as prevented development of atheromatous changes in the thoracic aorta. Cornelian cherry significantly increased PPARα protein expression in the liver, indicating that its hypolipidemic effect may stem from enhanced fatty acid catabolism. Simvastatin treatment did not affect PPAR-α expression. Moreover, the cornelian cherry had a significant protective effect on diet-induced oxidative stress in the liver, as well as restored upregulated proinflammatory cytokines serum levels. In conclusion, we have shown loganic acid to be the main iridoid constituent in the European cultivar of the cornelian cherry, and proven that the cornelian cherry could have protective effects on diet-induced hypertriglicerydemia and atherosclerosis through enhanced PPARα protein expression and via regulating oxidative stress and inflammation. [ABSTRACT FROM AUTHOR]

Background The effect of the natural aging process on systemic redox homeostasis is previously documented. However, none of the studies specify the effect of experimental aging on systemic redox homeostasis. The purpose of this study is to clarify the ambiguity raised in preliminary reports as to mimetic aging dependency of the type and magnitude of oxidative damage on constituents of plasma. Methods In the current study, we investigated the interrelationship among various groups of the systemic oxidative damage markers such as protein oxidation products ( protein carbonyl groups, protein hydroperoxides, advanced oxidation protein products, protein thiol groups ), lipid peroxidation products ( malondialdehyde, lipid hydroperoxides, conjugated dienes ), glycoxidation adducts ( advanced glycation end products ), and antioxidant capacity ( ferric reducing/antioxidant power, Cu,Zn-superoxide dismutase, total thiol, non-protein thiol ). All these markers were measured in plasma of mimetically aged (MA) rats (5-month-old rats subjected to d -galactose-induced experimental aging), naturally aged (NA) rats (24-month-old), and their corresponding young controls (YC) (5 months old). Results and conclusions Our current results show that systemic oxidation markers of the MA group share significant similarities in terms of impaired redox homeostasis with the NA rats and may be considered as a reliable experimental aging model for intravascular aging. Additional methodological studies including d -galactose dosage and application time are warranted to clarify the potential involvement of all these systemic redox variations as mechanistic factors in the development of mimetic aging related intravascular deterioration. Reversing or preventing systemic oxidative damage in experimental and natural aging should therefore be considered the primary target for the development of effective therapeutic strategies to prevent or treat age-related vascular disorders. [ABSTRACT FROM AUTHOR]