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In this study, 11 dehydrodiferulic acids (DFAs) and 8 diethyl dehydrodiferulates (DEFs) were synthesized and evaluated by Trolox equivalent antioxidant capacity (TEAC) and 2,2′-diphenyl-1-picrylhydrazyl (DPPH) assays for their antioxidant properties to understand the Structure-Antioxidant Activity Relationship (SAR) of these dehydrodiferulates. In both assays, the order of antioxidant activity for all tested ferulic acid dimers were consistent except for 3-(4-Hydroxy-3-methoxy-benzylidene)-5-(4-hydroxy-3-methoxy-phenyl)-3H-furan-2-one ( 2 , 8-8-lactone DC DFA, not occurred naturally) being the best antioxidant by TEAC test. The order of antioxidant activity of diferulic acid ethyl esters, evaluated by both assays, was not consistent; however, TEAC and DPPH assays provided consistent results for certain set of ethyl diferulates. In this study most of dimeric ferulates, with three exceptions, showed higher radical-scavenging efficacy than the monomers. Comparing the antioxidant activities of the tested diferulates suggested that the phenolic hydroxyl group, electron donating methoxyl group, and stable conjugated transient structures dictate the antioxidant activity of diferulates. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Unprotected chronic exposure to solar radiation can contribute to premature skin cancer and sunscreens are a key factor to avoid those detrimental effects. Currently, there is a growing interest in the photoprotector and antioxidant potential of bioactive substances, such as rutin, that could increase the sun protection factor (SPF) value and, also, donate multifunctional characteristics to sunscreens. Recent in vitro findings indicated that rutin, when incorporated into sunscreens, can provide antioxidant activity and SPF improvement. However, clinical studies are fundamental to determine this activity, due to the lack of repeatability of in vitro methodology and low correlation with the in vivo data. We aimed at evaluating the clinical safety and in vivo SPF of rutin by comparing sunscreen formulations containing 0.1% (w/w) rutin, 3.0% (w/w) butyl methoxydibenzoylmethane and 8.0% (w/w) octyl dimethyl PABA (2-ethylhexyl 4-(dimethylamino)benzoato) with a similar bioactive-free preparation. Additionally, skin hydration, in vitro SPF and in vitro antioxidant activity of rutin, in association with the ultraviolet (UV) filters, were investigated. The safety profile of the formulations under sun-exposed skin conditions qualified the formulas for clinical efficacy assays. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) test confirmed the antioxidant properties of rutin, revealing around 40% increase in radical scavenging potential when the bioactive compound was present. Rutin in combination with the UV filters robustly elevated the clinical SPF around 70%, when compared with the bioactive-free formulation. To date, this is the first report in the specialized literature of an in vivo SPF measurement of a rutin-containing photoprotective preparation, supporting the claim that rutin is an effective and safe bioactive compound to be used in multifunctional sunscreens. [ABSTRACT FROM AUTHOR]

Abstract: Aims: The aim of this study was to characterize a fungal endophyte Y3 from pigeon pea (Cajanus cajan [L.] Millsp), as a novel producer of vitexin, and its culture medium optimization and antioxidant activity. Methods and Results: The endophyte from the leaves of pigeon pea was identified as Dichotomopilus funicola by the morphological and molecular characteristics. The most important medium variables affecting vitexin production in liquid culture of D. funicola Y3 were screened by Plackett–Burman design, and three culture medium constituents (i.e. l‐phenylalanine, salicylic acid and CuSO4·5H2O) were identified to play significant roles in vitexin production. The most significant factors were further optimized using by central composite design with response surface methodology. The DPPH radical‐scavenging assay indicated that fungal vitexin exhibited notable antioxidant activity with an EC50 value of 164 μg l−1. Conclusions: First, a novel endophyte vitexin‐producing Dichotomopilus funicola Y3 was isolated from pigeon pea (Cajanus cajan[L.] Millsp.). The maximum vitexin yield was obtained as 78·86 mg l−1 under the optimum culture medium constituents: 0·06 g l−1  l‐phenylalanine, 0·21 g l−1 salicylic acid, and 0·19 g l−1 CuSO4·5H2O in medium, which is 4·59‐fold higher than that in the unoptimized medium. Also, fungal vitexin clearly demonstrated its antioxidant potential. Significance and Impact of the Study: These findings provide an alternative source for large‐scale production of vitexin by endophytic fungal fermentation and have a promising prospect in food and pharmaceutical industry. [ABSTRACT FROM AUTHOR]

Mangaba has high content of vitamin C, carotenoids, phenolic compounds, substances able to scavenge free radicals and a mixture of pentacyclic triterpenes (amyrin, lupeol). The aim of this study was to obtain extracts of mangaba fruit from different methods at low and high pressure methods with distinct solvents. The low pressure methods were Soxhlet, maceration and ultrasound with water, ethanol and n-hexane and extraction with vegetable oils (olive and soybean). The supercritical fluid extraction (SFE) was evaluated at 300 bar and 40–60 °C with carbon dioxide and ethanol as cosolvent (5 and 10%). The processes were evaluated by its global yield and their extracts were analyzed as total phenolic compounds, antioxidant potential (DPPH, ABTS, β-carotene), thermal oxidation in oven and the volatile chemical profile. After SFE, the residue was submitted to another extraction at low pressure. Maceration with ethanol showed higher yield and antioxidant potential. Hexane was the only one solvent capable to solubilize α-amyrin. At high pressure was possible solubilize compounds (oleic, trans -oleic and palmitic acids) with excellent antioxidant potential by β-carotene method. The increase of ethanol concentration 5–10% as cosolvent improved the yield and antioxidant potential. The extraction with oil permitted to enrich the soybean oil with antioxidant compounds provided from mangaba fruit. Two mangaba extracts presented peroxide value 26% less than the control when submitted to accelerate thermal oxidation assay. The SFE residue extracted by maceration with ethanol showed to be an excellent source of polar compounds with high antioxidant potential. [ABSTRACT FROM AUTHOR]

The present investigation reports the development of PEG-modified liposomes for the delivery of naturally occurring resveratrol. PEG-modified liposomes were prepared by direct sonication of the phospholipid aqueous dispersion, in the presence of two PEG-surfactants. Small, spherical, unilamellar vesicles were produced, as demonstrated by light scattering, cryo-TEM, and SAXS. The aging of the vesicles was assessed by using the Turbiscan ® technology, and their physical stability was evaluated in vitro in simulated body fluids, results showing that the key features of the liposomes were preserved. The biocompatibility of the formulations was demonstrated in an ex vivo model of hemolysis in human erythrocytes. Further, the incorporation of resveratrol in PEG-modified liposomes did not affect its intrinsic antioxidant activity, as DPPH radical was almost completely inhibited, and the vesicles were also able to ensure an optimal protection against oxidative stress in an ex vivo human erythrocytes-based model. Therefore, the proposed PEG-modified liposomes, which were prepared by a simple and reliable method, represent an interesting approach to safely deliver resveratrol, ensuring the preservation of the carrier structural integrity in the biological fluids, and the antioxidant efficacy of the polyphenol to be exploited against oxidative stress associated with cancer. [ABSTRACT FROM AUTHOR]

Natural products, or secondary metabolites, obtained from fungal species associated with marine algae have been widely used in sunscreens due to their antioxidant activity and protective potential against solar radiation. The endophytic fungus isolated from Bostrychia radicans algae collected in the Rio Escuro mangrove, São Paulo State, Brazil, Annulohypoxylon stygium (Xylariaceae family) was studied to evaluate the photoprotective potential of its metabolites. The Annulohypoxylon genus can produce secondary metabolites with interesting cytotoxic, antibacterial and antioxidant properties and was never isolated before from a marine alga or had its metabolites studied for UV protection. The fungal culture (code As) extracted with dichloromethane: methanol (2:1) yielded 9 fractions (Asa to Asi) which were submitted to different chromatographic methodologies to obtain pure compounds, and to spectroscopic methodologies to elucidate their structures. Also, a screening was conducted to evaluate the qualitative production of the metabolites, besides the absorption in the UVA/UVB range, their photostability and phototoxicity potential using the 3T3 NRU phototoxicity test (OECD TG 432). This study led to the isolation of a novel compound, 3-benzylidene-2-methylhexahydropyrrolo [1,2-α] pyrazine-1,4-dione ( 1 ), from fractions Ase3 and Asf3; Ase1 was identified as 1-(1,3-Benzodioxol-5-yl)-1,2-propanediol ( 2 ), two metabolites were isolated as diastereomers (1 S ,2 R )-1-phenyl-1,2-propanediol ( 3 ) from Asd2 and (1 R ,2 R )-1-phenyl-1,2-propanediol ( 4 ) from Asd3, and Ase1 and 1,3-benzodioxole-5-methanol ( 5) from Asc1. The results obtained showed a great potential source of new molecules to be used as UVB filters in sunscreens, since substances 1 – 2 presented UVB absorption, had no phototoxic potential and were considered photostable. In conclusion, these compounds can be considered as a potential new class of molecules for photoprotection, since their photosafety and non-cytotoxicity were predicted using in vitro methods for topical use. Meanwhile, further efficacy assays shall be conducted for the establishment of their Sun Protection Factor (SPF). Also, this work provided new information concerning the metabolic profile of A . stygium , since it was possible to obtain two enantiomer compounds ( 3 ) and ( 4 ). One of them belonged to the same skeleton, but with a methylenedioxy moiety, showing the richest enzymatic pattern for this microorganism. [ABSTRACT FROM AUTHOR]

Formation of heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs) was examined to evaluate the impact of using vegetable oil as fat replacement on carcinogen formation in meat product. Pork patties were formulated with 40% fat replacement by olive oil, sunflower oil or grape seed oil, respectively and cooked at 180 °C or 220 °C. Control patties contained the highest amount of HCAs compared with all other patties at both temperatures. Olive oil and sunflower oil replacement completely inhibited formation of MeIQ (2-amino-3, 4-dimethylimidazo[4,5-f]quinoline), while grape seed oil completely inhibited MeIQx (2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline), 4,8-DiMeIQx (2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline) and PhIP (2-amino-1-methyl-6-phenylimidazo[4,5- b ]pyridine) in patties. Grape seed oil achieved the highest inhibition capacity compared with sunflower oil and olive oil. HCAs increased significantly with cooking temperature (p < 0.05), but no difference was observed in total PAHs for patties cooked at different temperature (p > 0.05). In conclusion, fat replacement with sunflower oil, olive oil or grape seed oil in pork patties could reduce the formation of HCAs without compromising eating quality. [ABSTRACT FROM AUTHOR]

Illicit drugs have been recently identified as a serious environmental problem because of the growing evidence regarding their occurrence in aquatic environment and potential toxicity towards non-target organisms. Among them, cocaine (COC) and its main metabolites, namely benzoylecgonine (BE) and ecgonine methyl ester (EME), are commonly measured in freshwaters worldwide at levels that might cause diverse sub-lethal effects to aquatic organisms. Thus, the present study was aimed at investigating the potential adverse effects induced by the exposure to environmental concentrations (0.04, 0.4, 4 and 40 nM) of COC, BE, and EME on zebrafish ( Danio rerio ) embryos at 96 h post fertilization. Cytotoxicity was assessed by the Trypan Blue exclusion method, while primary and fixed genetic damages were evaluated by the Single Cell Gel Electrophoresis (SCGE) assay, and the DNA diffusion assay together with the Micronucleus test, respectively. The involvement of oxidative stress in the mechanism of action (MoA) of all tested drugs was assessed by measuring the activity of defense enzymes (SOD, CAT, GPx, and GST) and the expression of their encoding genes. Exposure to COC and both metabolites significantly reduced cell viability, increased DNA fragmentation and promoted the onset of apoptotic cells and micronuclei in zebrafish embryos. Results from oxidative stress-related endpoints and gene expression suggested that the observed genotoxicity may be caused by an overproduction of free radicals that imbalanced the oxidative status of embryos. The integration of biomarker responses into a synthetic index showed that at each tested concentration, BE and EME had a similar toxicity and were both more toxic than COC. Our data confirmed the potential toxicity of environmental concentrations of COC, BE, and EME, suggesting the need of further in-depth studies to shed light on their MoA and long-term toxicity towards non-target aquatic species. [ABSTRACT FROM AUTHOR]

An inflammatory reaction occurs following biomaterial implantation in the body, which produce toxic byproducts such as reactive oxygen species (ROS). Although ROS is required to clear the wound, excessive ROS can damage the tissue around the implant site, eventually leading to implant failure. One approach to control the inflammatory response is to incorporate an antioxidant into the biomaterial in order to scavenge ROS produced by activated phagocytes. In the present study, an organoselenium antioxidative compound was incorporated into a brushite cement, with the goal of scavenging ROS generated from activated primary human mononuclear leukocytes (MNCs), in vitro . The effect of the antioxidant on the physical properties of brushite cement, and its release from the cement were investigated via compressive strength, setting time, phase composition, and UV spectroscopy analysis. The physical properties of brushite remained unchanged following incorporation of the antioxidant. The antioxidant was slowly released from the cement, following a non-Fickian transport mechanism, with approximately 60% of the loaded antioxidant released over five days. The released antioxidant was then tested for its ability to scavenge ROS released by MNCs using the luminol amplified chemiluminescence assay. The results show that antioxidative released at both early stages (24 h) and late stages (120 h) retained its scavenging capacity and effectively reduced ROS production. These results indicate that brushite cements loaded with organoselenium compounds can modulate ROS production after implantation and potentially modulate the inflammatory response to improve device integration. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H 2 S) signaling involves polysulfide (RSS n SR′) formation on various proteins. However, the current lack of sensitive polysulfide detection assays poses methodological challenges for understanding sulfane sulfur homeostasis and signaling. We developed a novel combined assay by modifying Sulfide Antioxidant Buffer (SAOB) to produce an “Elimination Method of Sulfide from Polysulfide” (EMSP) treatment solution that liberates sulfide, followed with methylene blue (MB) sulfide detection assay. The combined EMSP-MB sulfide detection assay performed on low molecular weight sulfur species showed that sulfide was produced from trisulfide compounds such as glutathione trisulfide and diallyl trisulfide, but not from the thiol compounds such as cysteine, cystine and glutathione. In the case of plasma proteins, this novel combined detection assay revealed that approximately 14.7, 1.7, 3.9, 3.7 sulfide mol/mol released from human serum albumin, α 1 -anti-trypsin, α 1 -acid glycoprotein and ovalbumin, respectively, suggesting that serum albumin is a major pool of polysulfide in human blood circulation. Taken together with the results of albumins of different species, the liberated sulfide has a good correlation with cysteine instead of methionine, indicating the site of incorporation of polysulfide is cysteine. With this novel sulfide detention assay, approximately 8,000, 120 and 1100 μM of polysulfide concentrations was quantitated in human healthy plasma, saliva and tear, respectively. Our promising polysulfide specific detection assay can be a very important tool because quantitative determination of polysulfide sheds light on the functional consequence of protein-bound cysteine polysulfide and expands the research area of reactive oxygen to reactive polysulfide species. [ABSTRACT FROM AUTHOR]

Tomato seed contains proteins of high nutritional value and nutraceutical properties, which can be recovered for application as food additives. In this study, we investigated the use of a Lactobacillus plantarum strain to obtain high-added-value peptides from the fermentation process using tomato seed meal extract as the substrate. Potentially tomato seed meal extract have antioxidant activity which is correlated to the amino acid structures, compositions and sequences. After 24 h of fermentation, the radical scavenging activity of the isolated extract was increased by 87%. The increase of antioxidant activity is potentially attributed to the production of different bioactive peptides bio transformed during fermentation. L. plantarum growth on tomato seed meal extract as substrate reduced content of crude and soluble proteins by 18.44% and 68.99%, respectively, after 24 h of fermentation. Gel filtration chromatography showed a depolymerization of high molecular weight of polymers. HPLC analysis showed a significant decrease in the concentration of total amino acids, especially glutamic acid and aspartic acid. FTIR results showed that the fermentation favors the production of new amides and aromatic compounds. The production of protease by L. plantarum was investigated and results showed that highest activity (401.45 U/ml) were obtained after 20 h of fermentation. Results confirmed that L. plantarum could degrade and convert tomato seed proteins into bioactive peptides that contributed positively to the improvement of antioxidant activity of the protein isolate. [ABSTRACT FROM AUTHOR]

Electrochemical sensors have attracted much attention for the quantification of various antioxidants in the recent times. Voltammetric methods are highly selective and sensitive tool for the determination of different antioxidants in biological samples at very low concentration. Antioxidant acts as a defence mechanism in a body against various pathogens. Electrochemical techniques are being applied for the screening of antioxidant capacity. These methods are rapid, reliable and simple for the analysis of compounds. Antioxidant compounds are reducing agents and can be easily oxidized on inert electrodes. The present review article summarizes the voltammetric detection of various endogenous antioxidant compounds reported during the last five years. [ABSTRACT FROM AUTHOR]

Jatropha (Jatropha curcas L.) is a plant native of Central and South America, but widely distributed in the wild or semi-cultivated areas in Africa, India, and South East Asia. Although studies are available in literature on the polyphenolic content and bioactivity of Jatropha curcas L., no information is currently available on plants grown in pedoclimatic and soil conditions different from the autochthon regions. The aim of the present work was to characterize the antioxidant system developed by the plant under a new growing condition and to evaluate the polyphenol amount in a methanolic extract of leaves. Along with these analyses we have also tested the antioxidant and cytoprotective activities on lymphocytes. RP-HPLC-DAD analysis of flavonoids revealed a chromatographic profile dominated by the presence of flavone C-glucosydes. Vitexin is the most abundant identified compound followed by vicenin-2, stellarin-2, rhoifolin, and traces of isovitexin and isorhoifolin. Methanolic extract had high scavenging activity in all antioxidant assays tested and cytoprotective activity on lymphocytes exposed to tertz-buthylhydroperoxide. The results highlighted a well-defined mechanism of adaptation of the plant and a significant content of secondary metabolites with antioxidant properties, which are of interest for their potential uses, especially as a rich source of biologically active products. [ABSTRACT FROM AUTHOR]

Sodium caseinate (NaCN) was incubated prior to and after hydrolysis with a microbial transglutaminase (TGase) and hydrolysed with Prolyve 1000. The resultant hydrolysates were tested for their immunomodulatory and antioxidant activity. TGase-treated hydrolysates significantly reduced ( p < 0.05) the production of IL-6 at 0.5 and 1 mg mL −1 and the non-TGase treated hydrolysate reduced the production of IL-6 at 1 mg mL −1 in concanavalin (ConA) stimulated Jurkat T cells. None of the samples had an effect on IL-2. The hydrolysates showed higher oxygen radical absorbance capacity assay and ferric reducing antioxidant power activity than unhydrolysed NaCN, but no significant ( p > 0.05) differences were found between the TGase-treated and non-TGase-treated samples. In the presence of hydrogen peroxide, the non-TGase-treated sample exhibited the highest DNA protective effect in U937 cells. These findings suggest that NaCN derived hydrolysates with and without treatment with TGase may exert specific antioxidant, genoprotective and anti-inflammatory effects. [ABSTRACT FROM AUTHOR]

Kenaf ( Hibiscus cannabinus L.) seed oil contains high nutrition value, suggesting its potential applications in food and nutraceutical fields. However, the poor water solubility and stability strictly limit its applications. A good physical stability of kenaf seed oil-in-water nanoemulsions stabilised by sodium caseinate, Tween 20 and β-cyclodextrin complexes were produced using high pressure homogeniser. A simple model of two-stage dynamic in vitro digestion was employed to investigate the releasing rate of bioactive compounds from kenaf seed oil-in-water nanoemulsions, compared to unencapsulated bulk oil. The particles size and structural changes during digestion were also evaluated. Digested nanoemulsions showed good lipid digestion (85.25%), good bioaccessibility of antioxidants (tocopherols and total phenolic contents) and lower degradation rate of phytosterols compared to digested bulk oil. This study provides good information about the characteristic and release behaviour of formulated kenaf seed oil-in-water nanoemulsions, which is important for the future application in food and nutraceutical industries. [ABSTRACT FROM AUTHOR]

Previous studies have demonstrated the harmful effects of atmospheric pollutants on cardiac systems because of the presence of particulate matter (PM), a complex mixture of numerous substances including trace metals. In this study, the toxicity of PM 2.5 from two regions, rural (PM 2.5 level of 8.5 ± 4.0 μg m −3 ) and industrial (PM 2.5 level of 14.4 ± 4.1 μg m −3 ) in Brazil, was investigated through in vivo experiments in rats. Metal accumulation and biochemical responses were evaluated after rats were exposed to three different concentrations of PM 2.5 in saline extract (10× dilution, 5× dilution, and concentrated). The experimental data showed the bioaccumulation of diverse trace metals in the hearts of groups exposed to PM 2.5 from both regions. Furthermore, mobilization of the antioxidant defenses and an increase in lipid peroxidation of the cardiac tissue was observed in response to the industrial and rural area PM 2.5 . Glutathione-S-transferase activity was increased in groups exposed to the 5× and concentrated rural PM 2.5 . Additionally, ATP-binding cassette (ABC) transporter activity in the cardiac tissue exposed to PM 2.5 was reduced in response to the 5× dilution of the rural and industrial region PM 2.5 . Histological analysis showed a decrease in the percentage of cardiac cells in the heart at all tested concentrations. The results indicate that exposure to different concentrations of PM 2.5 from both sources causes biochemical and histological changes in the heart with consequent damage to biological structures; these factors can favor the development of cardiac diseases. [ABSTRACT FROM AUTHOR]

Context:Various studies have shown that the leaf extracts ofSpondias mombinLinn (Anacardiaceae) possess pharmacological properties such as antioxidant and antiviral effects. However, no biological activity from its essential oil has been reported in literature. Objective:To analyse the chemical constituents, cytotoxic activity and antioxidant capability of the essential oils from fresh and dried leaves ofS. mombin. Materials and methods:Hydrodistillation using Clevenger-type apparatus was employed to obtain the essential oil. Oil analysis was performed using an HP 6890 Gas Chromatograph coupled with an HP 5973 Mass Selective Detector. The cytotoxicity bioassay was carried out using the brine shrimp lethality test (10,000–0.01 μg/mL). Additionally, the reactive oxygen species scavenging potential of the twoS. mombinoils (1000–200 μg/mL) were investigated using a hydroxyl radical scavenging and ferric iron reducing system. Results:Chemical analysis of essential oils fromS. mombinrevealed the presence of 41 compounds, with predominance of monoterpenoids, sesquiterpenoids and non-terpenoids derivatives. In both fractions, the principal component was β-caryophellene (27.9–30.9%), followed by γ-cadinene (9.7–12.3%). There was an increase in the oxygenated monoterpenoid contents and a concomitant decrease in the amounts of sesquiterpenoids hydrocarbons observed on drying the leaves. The oil obtained from the fresh leaves was more active than that obtained from dried leaves, with LC50values (from the brine shrimp lethality assay) of 0.01 and 4.78 μg/mL, respectively. The two oils (from fresh and dried leaves) at 1.0 mg/mL scavenged hydroxyl radical by 83% and 99.8%, respectively. Moreover, they reduced ferric ion significantly and compared favourably with vitamin C. Conclusions:Essential oil derived from the leaves ofS. mombincould hold promise for future application in the treatment of cancer-related diseases. [ABSTRACT FROM AUTHOR]

Chrysobalanus icacoL. is an underexplored plant found in tropical areas around the globe. Currently, there is no apparent information regarding the effectsC. icacofruits may exert in vivo or potential role in health promotion. This study aimed at providing evidence regarding the in vivo influence of this fruit on antigenotoxicity, antimutagenicity, and oxidative stress in rats. Male Wistar rats were treated with 100, 200, or 400 mg/kg body weight (bw)/dC. icacofruit for 14 d. Doxorubicin (DXR, 15 mg/kg bw, ip) was used for DNA damaging and as an oxidant to generate reactive oxygen species (ROS). Genomic instability was assessed by the comet assay and micronucleus (MN) test, while antioxidant activity was determined by oxidative burst of neutrophils.Chrysobalanus icacofruit polyphenols were quantified and characterized by high-performance liquid chromatography coupled to a diode array detector and tandem mass spectrometer (HPLC-DAD-MS/MS). The concentrations of 19 chemical elements were determined by inductively coupled plasma–mass spectroscopy (ICP-MS). Significant amounts of polyphenols, magnesium, and selenium were found inC. icacofruit. This fruit displayed in vivo antioxidant activity against DXR-induced damage in rat peripheral blood neutrophils, antigenotoxicity in peripheral blood cells, and antimutagenicity in bone-marrow cells and peripheral blood cells. Correlation analyses between endpoints examined indicated that the mechanism underlying chemopreventive actions ofC. icacofruit was attributed to inhibition of NADPH oxidase complex manifested as low levels of DNA damage in animals exposed to DXR. Data indicate that phytochemicals and minerals inC. icacofruit protect DNA against damage in vivo associated with their antioxidant properties. [ABSTRACT FROM AUTHOR]

This review presents some of the most recent aspects related to antioxidants and the basic kinetic models of inhibited autoxidation and analyzes the chemical principles of antioxidant capacity assays. Taking into account the reactions involved, in the antioxidant activity determinations, the assays can be classified into two main types: hydrogen atom transfer reactions and electron transfer. This review focuses on analytical methods used for antioxidant activity assay, published in the period 2009-2014. [ABSTRACT FROM AUTHOR]

Background: To determine the antimicrobial, antiproliferative and antioxidant activities of ethanolic, ethyl acetate and petroleum ether extracts of Psidiumguajava leaves. Methods: The antimicrobial activity was assessed using disc diffusion method on Staphylococcus aureus, Bacillus cereus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli and Salmonella typhi. The anti-proliferative activity was determined on HeLa cell lines. The anti-proliferative activity was assessed using MTT assay while antioxidant activity was determined using catalase and superoxide dismutase (SOD) assays. Results: The MTT results indicate that ethyl acetate and petroleum ether extracts have significantly inhibited the proliferation of HeLa cells as compared to the control. Antioxidant assays showed that catalase activity was insignificant for all extracts however the SOD activity was significant. All the extracts showed inhibitory zones against B. cereus while only ethanolic extract of P. guajava leaves was active against S. aureus. Conclusion: Psidiumguajava plant leaves extracts can be used as antiproliferative agent against HeLa cell line. [ABSTRACT FROM AUTHOR]

Flaxseeds are both a food ingredient and a natural source of antioxidants (e.g. lignans, PUFAs) and pro-oxidant contaminants (e.g. cadmium): the variable mixture of anti- and pro-oxidant substances may impact on the redox homeostasis of flaxseed-enriched foods. The antioxidant power is studied here as biochemical activity of flaxseeds in white wheat bread and as endpoint for possible screening of anomalous variations of bioactive mixtures (antioxidants vs . prooxidants) in food matrices. A bioprobe assay based on the superoxide dismutase (SOD) enzyme (6 channels of the multiprobe bioelectronic platform BEST ) was performed on white wheat bread with and without flaxseeds. Nine BEST channels were simultaneously used for validation and monitoring of measuring conditions (temperature, pH, conductivity). Findings were compared with quantitative analysis of antioxidants and pro-oxidant contaminants. Organic and aqueous extracts of both bread types were examined in parallel. The SOD-probe detected the difference in antioxidant power given by 10% flaxseed, thus supporting the use of antioxidant power detected by bioenzymatic screening as sensitive biochemical endpoint. Mixtures of bioactive molecules in foods generate biochemical activities that can be monitored as time-effective indicators of invariability, which is pivotal in the daily control of anomalies in food production and therefore in the protection of consumers′ health. [ABSTRACT FROM AUTHOR]

Eight phenolic compounds including: p-coumaric acid, vanillic acid, caffeic acid, chlorogenic acid, trolox, quercetin, curcumin, and resveratrol were treated with riboflavin (RF) photosensitization and in vitro antioxidant capacities of the mixtures were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2' azino bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays. Mixtures containing p-coumaric acid and vanillic acid under RF photosensitization showed increases in ferric ion reducing ability and radical scavenging activity of DPPH, whereas mixtures of other compounds had decreases in both radical scavenging ability and ferric reducing antioxidant power. Hydroxycoumaric acid and conjugated hydroxycoumaric and coumaric acids were tentatively identified from RF photosensitized p-coumaric acid, whereas dimmers of vanillic acid were tentatively identified from RF photosensitized vanillic acid. RF photosensitization may be a useful method to enhance antioxidant properties like ferric ion reducing abilities of some selected phenolic compounds. [ABSTRACT FROM AUTHOR]

From 6 samples of tropically grown fruits and leaves, 10 lactic acid bacteria belonging Leuconostoc, Weissella, and Lactobacillus species were isolated and identified by 16S rRNA gene sequencing and (GTG)5 fingerprinting. Acidification kinetics determined from BHI broth cultures showed genus-related patterns. In particular, Weissella cibaria appeared to act as a potent acidifier. Tolerance of isolates to acid, oxidative, or salt stress was highly variable and strain dependent. Isolate S14 ( Leuconostoc pseudomesenteroides) growth was not affected by the presence of 0.05% H2O2, while Lactobacillus spp. isolates (S17 and S29) were the most tolerant to pH 4.5. The growth of 4 isolates, S5 ( Leuconostoc mesenteroides), S14 and S10 ( Leuconostoc pseudomesenteroides), and S27 ( W. cibaria), was not affected by 5% NaCl. Nutritional beneficial properties were examined through measurement of antioxidant activities of short-term fermented pineapple juice, such as LDL oxidation and polyphenol content, and through exopolysaccharide formation from sucrose. Two isolates, S14 and S27, increased the antioxidant capacity of pineapple juice. The robust capacity of W. cibaria and of Leuconostoc pseudomesenteroides for vegetable lactic fermentation aimed to ameliorate food nutritional and functional quality was highlighted. [ABSTRACT FROM AUTHOR]

The objective of the present study was to assess the ecotoxicological responses of Pardosa pseudoannulata to a common environmental pollutant, cadmium. Third-instar spiderlings and adult spiders were exposed to sublethal concentrations of CdCl solution in their drinking water. The Cd content in P. pseudoannulata adults increased significantly with the number of days of exposure to a 0.2 mM CdCl solution, when exposed to 2 mM CdCl solution, the Cd content in the spiders increased sharply in the first two (male) or three (female) weeks, and then no significant changes were recorded following with the next three (male) or two (female) weeks exposure. Exposure of spiders to Cd contaminated drinking water resulted in reduced body mass, delayed development, fewer eggs and increased mortality. Significantly higher activities of superoxide dismutase, catalase and glutathione- s-transferase were recorded in the spiders after 7 day exposure to 0.2 mM CdCl solution. However, longer-term exposures or increased Cd concentrations did not result in significantly higher antioxidant enzyme activity relative to control treatment. [ABSTRACT FROM AUTHOR]

We exposed the microalgal strain, Chlorella sp. MM3, to unused or used engine oil, or their water accommodated fractions (WAFs) to determine growth inhibition and response of antioxidant enzymes. Oil type and oil concentration greatly affected the microalgal growth. Used oil at 0.04 % (0.4 g L) resulted in 50 % inhibition in algal growth, measured in terms of chlorophyll-a, while the corresponding concentration of unused oil was nontoxic. Similarly, used oil WAF showed significant toxicity to the algal growth at 10 % level, whereas WAF from unused oil was nontoxic even at 100 % concentration. Peroxidase enzyme in the microalga significantly increased with used oil at concentrations above 0.04 g L whereas the induction of superoxide dismutase and catalase was apparent only at 0.06 g L. Activities of the antioxidant enzymes increased significantly when the microalga was exposed to 75 and 100 % WAF obtained from used oil. The used oil toxicity on microalga could be due to the presence of toxic soluble mono- and polyaromatic compounds, heavy metals, and other compounds attained by the oil during its use in the motor engines. [ABSTRACT FROM AUTHOR]

Objective: This paper highlighted the effect of selected soil containing metals, viz. Cd, Cr, Cu, Fe, Ni, Pb and Zn on the biochemical compositions and antioxidant activity in leaf of 20 years old two Cassia fistula L. (CF) cultivars. The leaf samples were collected from CF grown on road sides from the states of Maharashtra and Karnataka in India. Methods: Antioxidant activity and total phenol contents from methanolic and aqueous leaf extract were evaluated by assays like oxygen radical absorbance capacities (ORAC), 2, 2/-Azino-bis (3-ethylbenzothiozoline-6-sulphonic acid) diammonium salt (ABTS) and folin-ciocalteu reagent methods respectively. Maximum dose dependent antioxidant activity was observed in methanol leaf extract of both the cultivars, but marginal variation observed in antioxidant activity. Results: The result revealed that total phenolic content was maximum in the methanolic leaf extract (11.40 ± 0.37 mg g-1 of gallic acid equivalent). A positive correlation between antioxidant activity and total phenol compounds was noticed from both the samples. Furthermore a significant correlation was observed between element contents and antioxidant activities. Conclusion: This was may be due to elements like Fe, Cu, and Zn for accumulation of secondary constituents in the methanolic leaf extract that are major contributors to the antioxidant potential of CF. There were no other heavy metals (Ni, Cd, Pb and Cr) reported in both the samples. [ABSTRACT FROM AUTHOR]

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Sorbicillinoids are important hexaketide metabolites derived from fungi. They have a variety of biological activities including cytotoxic, antioxidant, antiviral and antimicrobial activity. The unique structural features of the sorbicillinoids make them attractive candidates for developing new pharmaceutical and agrochemical agents. About 90 sorbicillinoids have been reported in the past few decades. This mini-review aims to briefly summarize their occurrence, structures, and biological activities. [ABSTRACT FROM AUTHOR]

Background: The secondary metabolites of the Artemisia genus are well known for their important therapeutic properties. This genus is one of the valuable sources of flavonoids and other polyphenols, but due to the low contents of these important metabolites, there is a need to either enhance their concentration in the original plant or seek alternative sources for them. The aim of the current study was to detect and enhance the yield of antioxidant compounds of Artemisia carvifolia Buch. HPLC analysis was performed to detect the antioxidants. With the aim of increasing flavonoid content, Rol gene transgenics of A. carvifolia were established. Two genes of the flavonoid biosynthetic pathway, phenylalanine ammonia-lyase and chalcone synthase, were studied by real time qPCR. Antioxidant potential was determined by performing different antioxidant assays. Results: HPLC analysis of wild-type A. carvifolia revealed the presence of flavonoids such as caffeic acid (30 μg/g DW), quercetin (10 μg/g DW), isoquercetin (400 μg/g DW) and rutin (300 μg/g DW). Compared to the untransformed plants, flavonoid levels increased 1.9-6-fold and 1.6-4-fold in rol B and rol C transgenics, respectively. RT qPCR analysis showed a variable expression of the flavonoid biosynthetic genes, including those encoding phenylalanine ammonia-lyase and chalcone synthase, which were found to be relatively more expressed in transformed than wild-type plants, thus correlating with the metabolite concentration. Methanolic extracts of transgenics showed higher antioxidant capacity, reducing power, and protection against free radical-induced DNA damage. Among the transgenic plants, those harboring rol B were slightly more active than the rol C-transformants. Conclusion: As well as demonstrating the effectiveness of rol genes in inducing plant secondary metabolism, this study provides insight into the molecular dynamics of the flavonoid accumulation pattern, which correlated with the expression of biosynthetic genes. [ABSTRACT FROM AUTHOR]

The present study was conducted to evaluate the effect of salinity stress on growth of Cassia italica and role of gamma amminobutyric acid (GABA) in mitigating the salt stress induced damaging effects. Antioxidant activity, level of endogenous growth hormones and other biochemical parameters were evaluated. Salt stress enhanced the production of reactive oxygen species (ROS) resulting in the enhanced lipid peroxidation which was however reduced by application of GABA. Increased lipid peroxidation in salt stressed plants caused an obvious reduction in the total lipid content as compared to GABA treated plants. The antioxidant enzymes were higher in GABA treated plants which indicated a reduction of oxidative damage. The concentrations of growth hormones like indole acetic acid (IAA), indole butyric acid (IBA), gibberellic acid-1 (GA1), and gibberellic acid-4 (GA4) were reduced by salt stress, while enhanced by GABA treatment. In addition GABA treated plants maintained lower levels of sodium and chloride ions as compared to salt stressed plants. It could be concluded that toxic effects of salt stress on growth, antioxidant system, hormones and mineral nutrients in Cassia italica could be alleviated by exogenous application of GABA. [ABSTRACT FROM AUTHOR]

Purpose: The paper tries to assess the protective effect of fisetin against ?OH-induced DNA damage, then to investigate the possible mechanism. Methods:The protective effect was evaluated based on the content of malondialdehyde (MDA). The possible mechanism was analyzed using various antioxidant methods in vitro, including ?OH scavenging (deoxyribose degradation), ?O2 - scavenging (pyrogallol autoxidation), DPPH? scavenging, ABTS?+ scavenging, and Cu2+-reducing power assays. Results: Fisetin increased dose-dependently its protective percentages against ?OH-induced DNA damage (IC50 value =1535.00±29.60 µM). It also increased its radical-scavenging percentages in a dose-dependent manner in various antioxidants assays. Its IC50 values in ?OH scavenging, ?O2 - scavenging, DPPH? scavenging, ABTS?+ scavenging, and Cu2+- reducing power assays, were 47.41±4.50 µM, 34.05±0.87 µM, 9.69±0.53 µM, 2.43±0.14 µM, and 1.49±0.16 µM, respectively. Conclusion: Fisetin can effectively protect DNA against ?OH-induced oxidative damage possibly via reactive oxygen species (ROS) scavenging approach, which is assumed to be hydrogen atom (H?) and/or single electron (e) donation (HAT/SET) pathways. In the HAT pathway, the 3',4'-dihydroxyl moiety in B ring of fisetin is thought to play an important role, because it can be ultimately oxidized to a stable ortho-benzoquinone form. [ABSTRACT FROM AUTHOR]

The crude polysaccharides were extracted from the fruiting bodies of Calocybe indica (CIP). The antioxidant activities of CIP were evaluated both in vitro and in vivo . Chemical characteristics of the polysaccharides were investigated. In in vitro antioxidant assay, CIP showed noticeable 2,2-diphenyl-1-picryl-hydrazyl (DPPH), hydroxyl radical scavenging activities, reducing power and lipid peroxidation inhibition. Chemical analysis showed the presence of carbohydrate, protein and the FTIR spectra revealed the presence of general characteristic absorption peak of the polysaccharides. For in vivo antioxidant activity, two different doses of CIP were orally administrated over a period of 6 weeks in a d -galactose ( d -gal) induced aged mice model. Significantly lowered activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), levels of glutathione (GSH) and elevated malondialdehyde (MDA) levels were observed in brain and serum of d -galactose induced rats, when compared to control rats. Administration of CIP significantly raised the activities of SOD, CAT, GPx, levels of GSH and lowered the levels of MDA in mice brain and serum in a dose-dependent manner. The results suggested that CIP had potent antioxidant activity and could minimize the occurrence of age-associated disorders associated with involvement of free radicals. [ABSTRACT FROM AUTHOR]

The antioxidant capacity of cysteine, glutathione, N-acetylcysteine, and ascorbic acid to reduce Methylene Blue to colourless Leucomethylene Blue was analysed. Interestingly, transient exposure of Leucomethylene Blue to sunlight resulted in a reversible oxidation reaction and thus, provided a fast, easy, and simple quantitative assay to determine antioxidant capacity and photostability of biologically relevant antioxidants. [ABSTRACT FROM AUTHOR]

Introduction: The boldo leaf has several traditional folk medicinal uses, such as for gallbladder, hepatic problems, digestive disorders, rheumatism and others. In the work reported herein, botanic profiling, extraction optimization by Soxhlet, quantification of boldine by an easy/simple to run HPLC method and antioxidant assay are proposed for the quality assurance of boldo dried leaves, standardized extracts, dried extracts, tablets and capsules. Materials and Methods: In this present work we are studying a systematic approach in the quality assurance study of quality assurance for Peumus boldus M products by the ascertainment of pharmacobotanic parameters for boldo identification, investigation of the extraction parameters by Soxhlet method, development and validation of an easy/simple to run HPLC method to quantify boldine in the raw drug, extracts, commercial tablets, capsules and coated tablets, and antioxidant assay. Results: The plant material was submitted to a pharmacognostic evaluation through morpho-anatomical diagnosis, showing that starlike trichomes can be used for boldo authentication. The HPLC validated analytical method is reliable, accurate and precise for boldine quantification. Furthermore, the Soxhlet extraction conditions were optimized. Conclusion: The methods proposed in this paper can be used for the quality assurance of boldo dried leaves, standardized extracts, dried extracts, tablets and capsules. [ABSTRACT FROM AUTHOR]

3,5-dihydroxy-4-ethyl-trans-stilbene (DETS) is a natural stilbene, which was first identified as bioactive bacterial secondary metabolite isolated from Bacillus cereus associated with a rhabditid entomopathogenic nematode. The present study was intended to investigate the antioxidant and anticancer activity of this compound in vitro. Antioxidant activity was investigated by assaying DPPH free radical scavenging, superoxide radical-(O2-) scavenging, hydroxyl radical scavenging and metal chelating activity, which proved that the compound is a powerful antioxidant. The metal chelating activity of DETS was higher than butylated hydroxyanisol (BHA) and gallic acid, two well-known antioxidants. As the molecule exhibited strong antioxidant potential, it was further evaluated for cytotoxic activity toward five cancer cells of various origins. Since the compound has a strong structural similarity with resveratrol (trans-3,4,5-trihydroxystilbene), a well-studied chemopreventive polyphenolic antioxidant, its anticancer activity was compared with that of resveratrol. Among the five cancer cells studied, the compound showed maximum cytotoxicity toward the human melanoma cell line, [A375, IC50: 24.01 μM] followed by cervical [HeLa-46.17 μM], colon [SW480-47.28 μM], liver [HepG2-69.56 μM] and breast [MCF-7-84.31 μM] cancer cells. A375 was much more sensitive to DETS compared to the non-melanoma cell line, A431, in which the IC50 of the compound was more than double (49.60 μM). In the present study, the anticancer activity of DETS against melanoma was confirmed by various apoptosis assays. We also observed that DETS, like resveratrol, down-regulates the expression status of major molecules contributing to melanoma progression, such as BRAF, b-catenin and Brn-2, all of which converge in MITF-M, the master regulator of melanoma signaling. The regulatory role of MITF-M in DETS-induced cytotoxicity in melanoma cells was confirmed by comparing the cytotoxicity of DETS in A375 cells (IC50-24.01 μM), with that in SK-MEL-2 (IC50-67.6 μM), another melanoma cells which highly over-express MITF-M. The compound arrests the cells at S-G2 transition state of the cell cycle, as resveratrol. Our results indicate that DETS is a powerful antioxidant, having anticancer efficacy comparable with that of resveratrol, and is a potential candidate to be explored by in vivo studies and in-depth mechanistic evaluation. To our knowledge, this is the first report on the antioxidant and anticancer properties of DETS. [ABSTRACT FROM AUTHOR]

This work aimed to evaluate the efficiency of treating plant tissue with enzymatic agent ViscoStar 150L for the extraction of biologically active compounds. In the current study the screening of extraction methods from citrus fruit peels (grapefruit, lemon, orange) was performed. The samples treated with enzymatic agent ViscoStar 150L showed better extraction results than the traditional ethanol/water extraction method. Citrus peels' extracts assayed for antioxidant activity (determined as ferric reducing antioxidant power -- FRAP) decreased in the following order: grapefruit > orange > lemon. The enzymatic agent ViscoStar 150L proved to have a positive synergic effect on juice yield from cowberry previously treated with a complex pectolytic enzymatic agent. The enzymatic agent ViscoStar 150L proved to have a synergic effect on grain grist mashes previously treated with an amylolytic enzymatic agent, the inhibitor activity of the compounds produced by actinomycetic microorganisms grown on substrates based on these mashes being higher than that of previously known inhibitors. [ABSTRACT FROM AUTHOR]

High-throughput individual diagnostic dose assessment is essential for medical management of radiation-exposed subjects after a mass casualty. Cytogenetic assays such as the Dicentric Chromosome Assay (DCA) are recognized as the gold standard by international regulatory authorities. DCA is a multi-step and multi-day bioassay. DCA, as described in the IAEA manual, can be used to assess dose up to 4–6 weeks post-exposure quite accurately but throughput is still a major issue and automation is very essential. The throughput is limited, both in terms of sample preparation as well as analysis of chromosome aberrations. Thus, there is a need to design and develop novel solutions that could utilize extensive laboratory automation for sample preparation, and bioinformatics approaches for chromosome-aberration analysis to overcome throughput issues. We have transitioned the bench-based cytogenetic DCA to a coherent process performing high-throughput automated biodosimetry for individual dose assessment ensuring quality control (QC) and quality assurance (QA) aspects in accordance with international harmonized protocols. A Laboratory Information Management System (LIMS) is designed, implemented and adapted to manage increased sample processing capacity, develop and maintain standard operating procedures (SOP) for robotic instruments, avoid data transcription errors during processing, and automate analysis of chromosome-aberrations using an image analysis platform. Our efforts described in this paper intend to bridge the current technological gaps and enhance the potential application of DCA for a dose-based stratification of subjects following a mass casualty. This paper describes one such potential integrated automated laboratory system and functional evolution of the classical DCA towards increasing critically needed throughput. [ABSTRACT FROM AUTHOR]

Neurotransmission unavoidably increases mitochondrial reactive oxygen species. However, the intrinsic antioxidant defense of neurons is weak and hence the mechanism whereby these cells are physiologically protected against oxidative damage is unknown. Here we found that the antioxidant defense of neurons is repressed owing to the continuous protein destabilization of the master antioxidant transcriptional activator, nuclear factor-erythroid 2-related factor-2 (Nrf2). By contrast, Nrf2 is highly stable in neighbor astrocytes explaining their robust antioxidant defense and resistance against oxidative stress. We also show that subtle and persistent stimulation of N-methyl-d-aspartate receptors (NMDAR) in astrocytes, through a mechanism not requiring extracellular Ca2+ influx, upregulates a signal transduction pathway involving phospholipase C-mediated endoplasmic reticulum release of Ca2+ and protein kinase Cδ activation. Active protein kinase Cδ promotes, by phosphorylation, the stabilization of p35, a cyclin-dependent kinase-5 (Cdk5) cofactor. Active p35/Cdk5 complex in the cytosol phosphorylates Nrf2 at Thr395, Ser433 and Thr439 that is sufficient to promote Nrf2 translocation to the nucleus and induce the expression of antioxidant genes. Furthermore, this Cdk5-Nrf2 transduction pathway boosts glutathione metabolism in astrocytes efficiently protecting closely spaced neurons against oxidative damage. Thus, intercellular communication through NMDAR couples neurotransmission with neuronal survival. [ABSTRACT FROM AUTHOR]

The synthesis of antioxidant compounds bearing pharmacologically active groups has become a research interest in the last decade. A series of hydrazones containing a butylated hydroxyl group were synthesized from 2-((3,5-di-tert-butyl-4-hydroxybenzyl)thio)acetohydrazide and various benzaldehyde derivatives, and their radical scavenging activity was explored by 2,2-diphenyl-1-picrylhydrazyl ( DPPH) assay and computational calculations. Based on the results, the effects of different substituents on the DPPH IC50 values were discussed. The bond dissociation enthalpies ( BDE) of OH and NH bonds and the spin density ( SD) values of the compounds were calculated using the density functional theory ( DFT) to determine the theoretical capability of the hydrazones as radical scavengers. Based on the results, the effects of the thioether group and the substituent groups next to the NH bond on the BDE values were also discussed. [ABSTRACT FROM AUTHOR]

The skin sensitization potential of chemicals has been determined with the use of the murine local lymph node assay (LLNA). However, in recent years public concern about animal welfare has led to a requirement for non-animal risk assessment systems for the prediction of skin sensitization potential, to replace LLNA. Selection of an appropriate in vitro test or in silico model descriptors is critical to obtain good predictive performance. Here, we investigated the utility of artificial neural network (ANN) prediction models using various combinations of descriptors from several in vitro sensitization tests. The dataset, collected from published data and from experiments carried out in collaboration with the Japan Cosmetic Industry Association (JCIA), consisted of values from the human cell line activation test (h-CLAT), direct peptide reactivity assay (DPRA), SH test and antioxidant response element (ARE) assay for chemicals whose LLNA thresholds have been reported. After confirming the relationship between individual in vitro test descriptors and the LLNA threshold (e.g. EC3 value), we used the subsets of chemicals for which the requisite test values were available to evaluate the predictive performance of ANN models using combinations of h-CLAT/DPRA ( N = 139 chemicals), the DPRA/ARE assay ( N = 69), the SH test/ARE assay ( N = 73), the h-CLAT/DPRA/ARE assay ( N = 69) and the h-CLAT/SH test/ARE assay ( N = 73). The h-CLAT/DPRA, h-CLAT/DPRA/ARE assay and h-CLAT/SH test/ARE assay combinations showed a better predictive performance than the DPRA/ARE assay and the SH test/ARE assay. Our data indicates that the descriptors evaluated in this study were all useful for predicting human skin sensitization potential, although combinations containing h-CLAT (reflecting dendritic cell-activating ability) were most effective for ANN-based prediction. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The aim of the present study was to extract lignin from sugarcane bagasse followed by its structural characterization, oxidation, and evaluation of antioxidant activities. Lignin was extracted in a process involving different concentrations (1, 5, and 10 %) of NaOH solutions. The chemical composition of untreated and treated bagasse samples was analyzed which clearly showed that the delignification was found to be maximum with 10 % NaOH. The scanning electron microscopy (SEM) images of untreated and treated samples of bagasse were taken to study the physical changes occurred in the bagasse during different treatments. Lignin extracted was purified with acidified water and oxidized with 10 % HO. Both lignin and oxidized lignin were structurally characterized using Fourier-transformed infrared (FTIR), H, and C NMR spectra. The antioxidant potential of lignin and its oxidized derivative was evaluated by radical scavenging activity using DPPH method. Lignin was found to have higher antioxidant activity than oxidized lignin. This was attributed to a higher number of phenolic groups in lignin than in oxidized lignin. Both lignin and its oxidized derivative were observed to have higher antioxidant activity than 3,5-di- tert-butyl-4-hydroxytoluene (BHT) and lower than 3- tert-butyl-4-hydroxyanisole (BHA). It was concluded that sugarcane bagasse lignin and its oxidized derivative could be used as potential antioxidant of food oils and fats. [ABSTRACT FROM AUTHOR]

Antioxidants are of primary value biologically since they restrict the damage that reactive free radicals can do to cells and cellular components. These reactive free radicals are produced in cells and tissues in various ways, e.g., by the impact of radiation, by the transition metal catalysis and by redox processes often involving enzymes. In many cases, a reactive free radical arises as a result of a metabolic process within a cell, which is called metabolic activation and is of considerable significance with respect to the mechanism of action of some chemical carcinogens. [ABSTRACT FROM AUTHOR]

The total antioxidant activity of three apple cultivars conventionally farmed (Jonagold, Golden Delicious and Idared) and two cultivars organically farmed (Jonagold and Golden Delicious) were investigated by electron paramagnetic resonance (EPR) spectroscopy. The spin label used for experiments was TEMPO radical (2,2,6,6-tetramethylpiperidine-1-oxyl) with a well-defined EPR spectrum consisting of three equidistant peaks. The results obtained indicated difference in the total antioxidant activity of apples grown in two different ways, conventional and organic, as well as between different cultivars grown in the same way. The Golden Delicious cultivar is richer in antioxidants than the Jonagold and Idared, regardless of the method of farming. The difference between them is higher in conventionally grown apples than in organically farmed apples. Experimental data was fitted with non-linear curve fit for exponential decay of the first order based on the Levenberg-Marquardt method. The high values of the R² parameters for all data indicated correctness in the proposition of exponential decay of the first order as a model describing the dynamic properties of spin labels which diminish in the presence of fresh apple juice. [ABSTRACT FROM AUTHOR]

Five sweet orange (Citrus sinensis Osbeck) varieties cultivated in Huelva (Spain) and picked at two seasons during two consecutive years, were characterized for their antioxidant activity (free radicals scavenging activity, reducing power and lipid peroxidation inhibition) and vitamin content (vitamin E and vitamin C). The effects induced by sweet orange variety and stage of maturity were comprehensively compared by applying 2-way ANOVA and linear discriminant analysis. The results indicated higher differences in antioxidant activity and vitamin contents in response to the effect of the harvesting season, when compared to the effect of sweet orange variety. Nevertheless, the results observed in 2012 showed less marked differences among the assayed sweet orange varieties. Either way, it might be concluded that oranges sampled in January show the highest antioxidant activity and vitamin contents. Furthermore, concerning the properties evaluated in this work, all sweet orange varieties represent good alternatives, except for Rhode Summer, which would not be the preferable choice as a target to enhance sweet orange overall characteristics. [ABSTRACT FROM AUTHOR]

There is an increasing interest in the utilization of renewable resources for the production of food packaging. Among the biopolymers, starches from several sources are considered promising materials for this purpose, because they are biodegradable, inexpensive and available worldwide. Antioxidant food packaging films were produced by incorporating mango pulp and yerba mate extract into a cassava starch matrix. The bio-based films were used to pack palm oil (maintained for 90 days of storage) under accelerated oxidation conditions (63% RH/30°C) in order to simulate a storage experiment. Palm oil packaged in these films exhibited a decreased oxidative process rate, which was attributed to the yerba mate and mango pulp in a concentration-dependent fashion. The evolution of the peroxide value contents indicated that, in general, the films with high concentrations of additives improved palm oil stability. Mechanical, physical and barrier properties of the developed film indicated that the addition of these bioactive compounds modified their properties significantly (p<0.05). [ABSTRACT FROM AUTHOR]

An efficient synthetic route to the resveratrol oligomers quadrangularin A and pallidol is reported. It features a scalable biomimetic oxidative dimerization that proceeds in excellent yield and with complete regioselectivity. A systematic evaluation of the natural products and their synthetic precursors as radical-trapping antioxidants has revealed that, contrary to popular belief, this mode of action is unlikely to account for their observed biological activity. [ABSTRACT FROM AUTHOR]

This study reports the essential oil composition and antioxidant activity of the essential oil extract of aerial parts of Achillea Wilhelmsii. GC/MS analysis identified thirty compounds representing 94.48% of the oil. The main components comprising 86.99% of the oil were a-thujene (6.11%), a-pinene (5.11%), sabinene (5.23%), p-cymene (7%), 1,8-cineole (6%), linalool(10%), camphor (8.43%), thymol (18.98%) and carvacrol (20.13%). The samples were screened for their antioxidant activities using 2,2-diphenyl-1- picrylhydrazyl (DPPH) radical assay methods. Thymol (13.0±0.1 µg/ml) and carvacrol (15±0.0 µg/ml) showed appreciable antioxidant activity in DPPH test. [ABSTRACT FROM AUTHOR]

Pumpkin flours were produced by hot-air oven drying or freeze-drying, with or without a pre-treatment with metabisulfite. Freeze-dried pumpkin flour had deep orange color while metabisulfite caused loss of fresh pumpkin color. Freeze-drying let to better functional properties: higher water holding capacity (92 mL 100 g −1 ), oil binding capacity (314 mL 100 g −1 ) and synergy with BSA for emulsification. Oven drying and metabisulfite pre-treatment both increased phenolic contents and bioaccessible phenolics (1237, 457 mg of GAE 100 g −1 DW, respectively). The most abundant phenolic acids were p-hydroxybenzoic (0.83–1.68 mg g −1 ), followed by caffeic acid (0.68–1.28 mg g −1 ) and chlorogenic acid (0.35–0.92 mg g −1 ) in all pumpkin flours. Oven-drying and metabisulfite pre-treatment led to higher phenolic acid levels. Oven-dried pumpkin flour without metabisulfite pre-treatment may be more appropriate as a functional and nutritional ingredient. [ABSTRACT FROM AUTHOR]

We previously developed an electron paramagnetic resonance (EPR)-based oxygen radical absorbance capacity (ORAC-EPR) assay that can be used to evaluate the radical-scavenging activity (RSA) of samples by employing the established EPR spin trap method. In this assay, since reactive oxygen radicals are generated by the photolysis of the azo-radical initiator by ultraviolet (UV) light irradiation, the sample in the assay mixture exposed to UV light may also get photolysed. In the present study, irradiation of the sample was avoided; a novel radical-generation method was adopted in the ORAC-EPR assay, and the feasibility of the modified assay was assessed. RSA was evaluated in the modified as well as in the conventional assay with three antioxidants. Although the RSA values normalized to the spin trap reagent obtained with the modified assay were approximately 20% lower than those obtained with the conventional assay, the maximum difference between the RSA values of the two methods was 15% when this data were normalized to the standard antioxidant Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid). Elucidation of the generation mechanism of the oxygen radicals and the reasons for lower RSA is necessary prior to application of the new radical-generation method coupled to ORAC-EPR assay. [ABSTRACT FROM AUTHOR]