High Levels Of Antioxidant Activity Research Articles

After In Vitro Digestion, Jackfruit Flake Affords Protection against Acrylamide-Induced Oxidative Damage.

Some studies have demonstrated that acrylamide (AA) was correlated with oxidative stress, resulting in physical damage. The jackfruit flake was an immature pulp that contained a high level of antioxidant activity. This study aimed to assess the defensive efficacy of jackfruit flake in AA-induced oxidative stress before and after simulated gastrointestinal digestion. Our results indicate that the total polyphenol content of Jackfruit flake digest (Digestive products of jackfruit flake after gastrointestinal, JFG) was diminished; however, JFG had raised the relative antioxidant capacity compared to Jackfruit flake extract (JFE). Additionally, the results of High Performance Liquid Chromatography-Mass Spectrometry (HPLC-MS) implied that a proportion of compounds were degraded/converted into other unknown and/or undetected metabolites. Further, by high content analysis (HCA) techniques, JFG markedly reduced cytotoxicity and excessive production of reactive oxygen species (ROS) in cells, thereby alleviating mitochondrial disorders. In this study, it may be converted active compounds after digestion that had preferable protective effects against AA-induced oxidative damage.

Kandungan Gizi, Beta Karoten dan Antioksidan pada Tepung Pisang Tongka Langit (Musa troglodytarum L.)

Banana fruit cultivar Tongka Langit is a typical plant from Moluccas which has not widely used and observed just yet. It has been believed and used by locals to relieve body heat, clean the kidneys, and keep the health of the digestion tract, but without scientific proof. This study aims the nutrition content of Tongka Langit flour, along with its carotenoids, beta carotene, and antioxidant content. The banana fruit was dried at 60 oC for 2 hours. Banana flour had been analyzed for moisture content, levels of ashes, levels of protein, the fibers, carbohydrates, vitamin C, mineral, carotenoids and antioxidant. It had been found that Tongka Langit flour contained 331,03 calories, 4,66% protein, 83,72% carbohydrate and 16,59% dietary fibers. Tongka Langit flour contained 7,92 mg/ 100 mg carotenoid total which 18,56% was beta carotene. As much as 0.35 mg/kg flavonoid was also found, along with its high level of antioxidant activity.

Comparison of acrylamide and furan concentrations, antioxidant activities, and volatile profiles in cold or hot brew coffees.

The aim of this study was to investigate the formation of furan and acrylamide and to compare antioxidant capacities and volatile compounds in cold or hot brewed coffees. Cold brews were prepared at 5°C and 20°C for 12h. using steeping and dripping, and hot brews were prepared at 80°C and 95°C for 5min. using the pour-over method. Furan contents of cold steeping at 5°C and hot brewed at 80°C showed the higher levels significantly (p < 0.05), which were 17.0 ± 0.5 and 10.6 ± 0.1ng/mL, respectively. However, acrylamide contents in cold steeping at 5°C and hot brew at 80°C showed lower levels, which were 4.1 ± 0.4 and 3.5 ± 0.1ng/mL respectively. Cold brews at 20°C showed the highest levels of antioxidant activities while hot brews showed similar levels with cold brews at 5°C. This study confirms that levels of different beneficial and hazardous chemical compounds could be manipulated by adjusting the coffee extraction conditions.

Caucasian endemic medicinal and nutraceutical plants: in-vitro antioxidant and cytotoxic activities and bioactive compounds.

In order to assess traditional claims about the therapeutic potential of Caucasian endemic medicinal plants and to select plants for phytochemical research, nine plant species were selected and assessed for their in-vitro antioxidant and cytotoxic activities. The metabolite profiles of some priority plants were analysed. Antioxidant effects were assessed using the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) system, lipid peroxidation and Folin-Ciocalteu methods. Cytotoxic activities were examined against human liver cancer cells (HepG2) using the Alamar Blue assay. Terpenoids of selected species were analysed by GC and GC-MS. Polyphenols were separated by HPLC. Thymus transcaucasicus, Heracleum transcaucasicum, Ribes armenum, Crataegus armena showed most promising antioxidant activity in ABTS model system. Moreover, Rubus takhtadjanii, C. armena, T. transcaucasicus showed a high level of antioxidant activity by inhibiting lipid peroxidation. C. armena and T. transcaucasicus expressed high-to-moderate cytotoxicity against HepG2 cells. The main terpenoids and polyphenols of Centaurea hajastana, C. armena and T. transcaucasicus were quantified. This study provides in-vitro data relevant for assessing the use of Caucasian endemic medicinal plants, most importantly C. armena and T. transcaucasicus as traditional antioxidant supplements and potential anticancer remedies. Metabolite profiles of some lead plants showed the nature of bioactive compounds of medical interest.

Qsar-analysis of 1-[2-(R-phenylimino)-4-methyl-3-(3-[morpholine-4-yl]propyl)-2,3-dihydro-1,3-thiazol-5-yl]ethane-1-one’s derivatives as potential antioxidants

Aim. The aim of study was to determine of the parameters of the molecular structure of new 1-[2-(R-phenylimino)-4-methyl-3-(3-[morpholine-4-yl]propyl)-2,3-dihydro-1,3-thiazol-5-yl]ethane-1-one derivatives and QSAR-analysis. The latter can be considered as the theoretical basis for de novo design of new potential antioxidants. Materials and methods. 14 new derivatives of 1-[2-(R-phenylimino)-4-methyl-3-(3-[morpholine-4-yl] propyl)-2,3-dihydro-1,3-thiazol-5-yl]ethane-1-one were involved in the study and their antioxidant activities were evaluated. Hyper-Chem 7.59 and BuildQSAR software were used for calculation of molecular descriptors and building the QSAR-models. Results. The calculation of number of molecular descriptors (electronic, steric, geometric, energy) was carried out for the tested compounds: 14 derivatives of 1-[2-(R-phenylimino)-4-methyl-3-(3-[morpholine-4-yl] propyl) -2,3-dihydro-1,3-thiazol-5-yl]ethane-1-one. For QSAR analysis, the compounds studied were divided into a training and test sample. The correlations between the antioxidant activity level and abovementioned molecular descriptors were shown in multivariate linear QSAR-model: Activity = ∑хіаі + bі, where xi – molecular descriptor. Based on the analysis of the obtained QSAR-models, it was found that antioxidant activity increases with decreasing of the area, molecular volume, lipophilicity, polarisation and increasing the magnitude of the dipole moment. The increase in the energy of the bonds, the energy of inter-nuclear interactions, the energy of the lower vacant molecular orbit and the reduction of the energy of hydration and energy of the higher vacant molecular orbitals also results in an increase in the antioxidant activity. The greatest effect of effective charges on atoms on the antioxidant activity was detected: the increase in the charge value on the morpholine cycle Oxygen and the decrease in the charge size on the Sulphur atom of the thiazole ring and the Oxygen atom of the acetyl group. QSAR models with better statistics were selected. QSAR models obtained are characterised by high predictive ability, determined both by internal and external validation and can be used for virtual screening of the antioxidant activity of substances of this class of compounds. Conclusions. 1). The study of the structure–activity relationships for 1-[2-(R-phenylimino)-4-methyl-3-(3- [morpholine-4-yl]propyl)-2,3-dihydro-1,3-thiazol-5-yl]ethane-1-one derivatives were carried out. 2). QSAR analysis revealed the following: polarisation, dipole moment, lipophilicity, energy parameters as well as the size of the molecule and its branching possessed the most significant effect on antioxidant activity; the antioxidant activities of the compounds were increased with the increase in their hydrophilic and reductive properties; the molecules with small volume and surface area showed the higher level of antioxidant activity. 3). Obtained QSAR models are proposed for antioxidant activity prediction within the above-mentioned row of compounds and can be considered as a theoretical basis for de novo design of new potential antioxidants.

An assessment of temporal variation in the low molecular weight phlorotannin profiles in four intertidal brown macroalgae

Phlorotannins are a group of highly bioactive marine polyphenols found exclusively in brown algae (Phaeophyceae) where they play an integral role in chemical defence. Owing to their high degree of reactivity, phlorotannins have attracted recent commercial interest with potential for application in areas such as pharma-, nutra- and cosmeceuticals. However, to date, little is known regarding their biosynthesis and the factors that drive their natural variability, particularly in relation to their chemical properties such as polymerisation and isomerisation - two factors which directly influence their degree of activity. Low molecular weight (LMW; <3.5 kDa) phlorotannin-enriched fractions have exhibited a high level of antioxidant activity yet their degree of natural variability within macroalgae is not known. This study aimed to, for the first time, assess the temporal variation of LMW phlorotannin chemical profiles of four intertidal brown macroalgae dominant along the west coast of Ireland – Pelvetia canaliculata, Fucus vesiculosus, Ascophyllum nodosum and Himanthalia elongata. Samples were collected at six different time points over two years (2014–2015) and assessed for temporal shifts in the chemical profile, content and antioxidant activity. Species-specific profiles were detected, with each species displaying varying degrees of polymerisation and isomerisation, which were linked to the in vitro antioxidant activity observed. While some temporal shifts were observed in the molecular weight composition of the LMW phlorotannin profiles, they, along with the degree of isomerisation, did not appear to correspond with large-scale temporal changes in irradiance or temperature regime of Galway Bay. The results emphasise the strong degree of natural variability associated with phlorotannin profiles which, in situ, are likely to be influenced by several parameters synergistically; future studies should investigate small-scale effects of physio-chemical parameters, as well as biological factors, at microhabitat level, which could be aided by a laboratory-based assessment of individual parameters.

Prospects of application of melanins as antiaging agents in elastomer compositions

AbstractThe paper presents findings of a study of physical‐chemical properties of sunflower husk melanins, as well as their influence on the thermal oxidative aging resistance of elastomer compositions. It has been found that melanins reveal a high level of antioxidant activity and can be used as antiaging agents in elastomer compositions.

Influence of Drying on the Phytochemicals and Antioxidant Properties of Bombax buonopozense (Gold Coast Bombax) Sepals

Dried sepals of red silk cotton plant (Bombax buonopozense) are incorporated into soups by some Ghanaian indigenes due to the antimicrobial and antioxidant properties. This study was aimed at determining the influence of drying (sun, solar, and oven drying) on phytochemicals and antioxidant properties of the sepals. DPPH radical scavenging activity method was used to determine the antioxidant activity, whereas total phenolics and tannin contents were determined by Folin-Ciocalteu’s method, and total flavonoids by Aluminium trichloride method. The results revealed the presence of alkaloids, tannins, total flavonoids, and total phenols. There was no significant difference (P> 0.05) in alkaloids and tannins contents of the dried sepals regarding the drying methods used. The solar-dried sepals showed highest level of antioxidant activity with EC50 of 0.063 mg/mL. There was also no significant difference (P> 0.05) in antioxidant activity with EC50 of the dried sepals regarding the drying methods used. The solar drying method preserved most of the antioxidant properties and tolerable levels of phytochemicals in the sepals which makes it a potential source of natural antioxidants and can help reduce degenerative oxidative stress in consumers.

Stability and instability processes in the calli of Fagopyrum tataricum that have different morphogenic potentials

The morphogenic callus (MC) of Fagopyrum tataricum contains a large amount of flavonoids, especially rutin, and exhibits a high level of antioxidant activity. A non-morphogenic callus (NC) may appear on the surface of the MC after two to three years of cultivation and is then subjected to a consistently high level of oxidative stress. The elucidation of the molecular background of this instability is essential for gaining a better understanding of the somaclonal variation mechanisms in tissue cultures that have different morphogenic potentials. Thus, in this study we show that continuous oxidative stress in a NC might be connected with a rapid senescence process and as a result, in the upregulation of the genes that are connected with the telomere complexity, ethylene biosynthesis and the expression of DNA methyltransferases. Moreover, we analysed the presence of the hydroxyproline-rich glycoproteins in the calli and demonstrated the differences between the MC and NC. The LM2 antibody can be useful as a marker of the cells in the MC that are embryogenically determined, while the MAC207 antibody seems to be a positive marker of a MC as its signal was absent in the NC. This study also provides the first report on the effect of trichostatin A on the DNA methyltransferases and demethylases in a MC.

Production, application and health effects of banana pulp and peel flour in the food industry.

The past 20years has seen rapid development of value-added food products. Using largely wasted fruit by-products has created a potential for sustainable use of these edible materials. The high levels of antioxidant activity, phenolic compounds, dietary fibres and resistant starch in banana pulp and peel have made this tropical fruit an outstanding source of nutritive ingredient for enrichment of foodstuffs. Accordingly, processing of separate banana parts into flour has been of interest by many researchers using different methods (oven drying, spouted bed drier, ultrasound, pulsed vacuum oven, microwave, spray drying and lyophilization). Regarding the high level of bioactive compounds, especially resistant starch in banana flour, the application of its flour in starchy foods provides a great opportunity for product development, even in gluten free foods. This review aims to provide concise evaluation of the health benefits of banana bioactive components and covers a wide range of literature conducted on the application of different parts of banana and the flour produced at various ripeness stages in the food industry. Of particular interest, the impact of drying methods on banana flour properties are discussed.

Baseline levels of antioxidant activities in Mytilus galloprovincialis along the coast of Cape Town, South Africa

Antioxidant activities in Mytilus galloprovincialis were determined from samples collected at Scarborough, Hout Bay, Green Point, Milnerton and Bloubergstrand in Cape Town, South Africa. Antioxidant enzyme activity was determined by measuring CAT, SOD and GSH. The total antioxidant capacity was measured using FRAP and ORAC, while the content and lipid peroxidation marker levels of CDs and TBARS. Antioxidant activities and responses in mussels varied between sites with significant correlations for 85% and 71% of all antioxidant measurements made for Fe and Zn, respectively. The oxidative stress results reported here are novel for the region and indicated that mussels in Cape Town do not have (relatively) high levels of antioxidant activities as a result of exposure to metals. The research undertaken suggests that antioxidant responses was an appropriate biomarker of exposure to metals but more environmental parameters should be considered when interpreting antioxidant responses in the natural environment.

PROSPECTS OF PRODUCTION OF ALLIUM SEEDS SPROUTS FORTIFIED WITH SELENIUM

Sprouts of agricultural crops seeds are considered to be functional food products with high content of antioxidants. Though seeds of Allium species plants are used in some countries as spices the possibilities of appropriate sprouts utilization have never been investigated so far. Evaluation of perennial and A. cepa seeds biofortification with selenium revealed high nutritional value of the resulting sprouts characterized not only by high selenium content exclusively in a form of selenomethyl selenocysteine (a natural anti carcinogen) but also with high levels of antioxidant activity and high polyphenol content. It was demonstrated that among seven studied representatives of Allium species Allium cepa variety Krasnoye krugevo and perennial onion Allium fistulosum give seeds sprouts with the highest levels of selenium (10500-11000 μg/kg d.w.), polyphenols (9.3-10.8 mg-eq GA/g d.w) and the largest values of antioxidant activity (14.7-17.1 mg-eq GA/g d.w.). Utilization of one g of dried seeds sprouts powder, fortified with selenium provides up to 15.7% of the adequate consumption level of selenium exclusively in a form of selenomethyl selenocysteine possessing powerful anti carcinogenic activity.

Effects of microwave heating on the antioxidant activities of tomato (Solanum lycopersicum)

The aim of this study is to estimate phytochemical constituents and antioxidant activities of tomato slices treated by microwave heating. Two treatments time were applied, 30 and 300 s. Quantitative analyses of phenols, flavonoids, lycopene, followed by the evaluation of the antioxidant activity by DPPH (2,2-diphenyl-1-picrylhydrazyl) and ion chelating methods, were conducted on ethanolic extracts. Results showed the presence of these bioactive phytonutrients in fresh tomato and that their biodisponibility increases with the duration of the selected heat treatment. The phytochemical content showed important levels of polyphenols (1.92, 1.96, 6.95 mg gallic acid equivalent/g fresh matter) and flavonoids (2.33, 2.57, 10.68 mg RE/g fresh matter), in addition to lycopene (5.772, 31.8654, 40.71 mg/kg fresh matter) of non-treated, treated tomatoes at 30 s and treated tomatoes at 300 s, respectively. Results also revealed a high level of antioxidant activity by both methods with IC50 of 1.69, 1.50, 1.33 µg/ml, for DPPH method and IC50 of 401, 360.5, 299.91 µg/ml, for ion chelating ability. Thus, in our study, we demonstrated that microwave treatments enhance the nutritional quality of tomato slices by enhancing the biodisponibility of some of its content. Higher treatment time gives better results.

The effect of Laurus nobilis L. essential oil and different packaging systems on the photo-oxidative stability of Chemlal extra-virgin olive oil.

This study was performed to determine the effect of the addition of Laurus nobilis L. essential oil (EO) (at 0.01% v/v) and of the packaging material (brown and transparent glass or PET) on the oxidative stability of Algerian extra-virgin olive oil (EVOO) stored for 90days at 25 ± 2°C under continuous exposure to fluorescent light (~ 900lux). Control and enriched EVOO was analysed after 30, 60 and 90days for various parameters. Bio-enrichment of EVOO with EO combined with packaging in brown glass enabled maintenance of the highest amounts of chlorophyll and carotenoids after 90days of accelerated photo-oxidation. The lowest total phenols content was found in EVOO without EO packed in transparent glass. EO enrichment and brown packaging preserved higher levels of antioxidant activity but could not preserve the oxidation indices until the end of the period of light exposition.

Using Resveratrol and Epigallocatechin-3-Gallate to Improve Cryopreservation of Stallion Spermatozoa With Low Quality

Reactive oxygen species levels in semen with low quality increased from 25% to about 40%. Resveratrol (Res) is a natural grape-derived phytoalexin, and epigallocatechin-3-gallate (EGCG) is the major polyphenol in green tea (Camellia sinensis); both molecules are known to have high levels of antioxidant activity. The aim of this study was to investigate the effects of this antioxidant's supplementation on cryopreservation of stallion semen with poor quality. Experiment 1: Experiment design to asses stallions semen quality (n = 3). Arabian stallions were managed for breeding with fresh, extended, or chilled semen during 2 years (in two breeding season) with a resulting per cycle pregnancy rate (103/41 estrus cycle/conception) of 39.80%. A total of 81 ejaculates were collected and evaluated in fresh condition (total and progressive motility, membrane integrity, acrosome defects, morphology, and abnormal DNA condensation). Evaluation of several ejaculates revealed that sperm production and semen quality mostly did not change during the breeding season, maintaining normal sperm production with poor quality. Experiment 2: 18 ejaculates, collected with Missouri model artificial vagina from Arabian stallion (n = 3). Extended semen was centrifuged at 600 × g for 10 minutes. To eliminate individual stallion variability, the resulting sperm pellets were pooled and divided in seven different treatments in a final concentration of 100 × 106 sperm/mL by using semiskimmed milk extender containing no supplements (control), and the following supplements with three different concentrations: Res 5, 10, and 20 μM (Res 1, Res 2, Res 3, respectively) and EGCG 25, 50, 100 μM (EGCG 1, EGCG 2, and EGCG 3, respectively). After thawing, all samples were maintained at 37°C for 10 minutes. Evaluation of motility, plasma membrane integrity, viability, mitochondria activity, DNA fragmentation, and lipid peroxidation was determined. For all semen parameters, the lower concentration of Res (5 μM) and EGCG (25 μM) did not show significant differences compared to control (P > .05). Relative to the control group, Res 2 had better (P < .05) postthaw total and progressive motility, yet the higher concentrations (Res 3) showed a negative effect on total motility. Percentage of membrane integrity, viability, and mitochondrial activity was significantly greater in Res 2 and EGCG 2 extenders in comparison with the control group, respectively (P < .05). Results showed that malondialdehyde concentration was lower in Res 2 and EGCG 2 groups. In conclusion, the present study showed that the antioxidant Res prevents DNA damages in our stallions. The addition of Res and EGCG before cryopreservation can ameliorate mitochondrial activity in stallions with low-quality semen. Although further studies are needed, the present work showed that Res and EGCG could be considered as cryopreservation procedures in stallions with low-quality sperm and possibly equine, to avoid or minimize DNA damages, and preserve sperm plasma membrane integrity and mitochondrial activity.

Diversity and Characterization of Endophytic Fungi Isolated From the Tropical Mangrove Species, Rhizophora mucronata, and Identification of Potential Antagonists Against the Soil-Borne Fungus, Fusarium solani.

Rhizophora mucronata is an important ecosystem entity of the Malaysian mangrove forest. Since the species grows in a harsh environment, any organism that is isolated from this species would be of huge interest due to its potential in having novel bioactive compounds. In the present work, we isolated, identified and characterized, a total of 78 fungal isolates harboring inside the leaf tissues of R. mucronata. Molecular identification using the nuclear ribosomal DNA internal transcribe spacer (ITS) sequences returned with high similarity matches to known sequences in the GenBank. Maximum likelihood analysis revealed the phylogenetic relationship of all isolates from this study. Most of the dominating fungal endophytes were from the genera Pestalotiopsis, followed by Alternaria and Cladosporium. Six isolates representing the genera Alternaria, Fusarium, Nigrospora, Pestalotiopsis, Phoma, and Xylaria, were further screened for their antagonism activities. Dual culture test assay revealed their inhibition percentages against the phytopathogenic fungus Fusarium solani between 45–66%, and 0.8–23% when using non-volatile test assay. Of the six isolates, only Fusarium lateritium and Xylaria sp. showed antibacterial activities against the pathogenic bacteria, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus, with the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) ranging from 0.5 to 2 mg/mL. The DPPH radical scavenging assay recorded a high level of antioxidant activity in Xylaria sp., 3-fold above that of F. lateritium. We demonstrate for the first time, two members belonging to the endophytic fungal community in the tropical mangrove species that have potential use as antagonists and antibacterial agents for future biotechnological applications.

Chemical Properties, Antioxidant Activities and Sensory Evaluation of Berry Vinegar

This study was carried out to examine the chemical properties, antioxidant activities and sensory scores of berry vinegar produced from 4 berry species, namely Morus alba L. (Mulberry), Vaccinium macrocarpon L. (Cranberry), Rubus idaeus L. (Rasberry), and Rubus laciniatus L. (Blackberry). Berry vinegars were produced via a 2-stage (alcoholic and acetous) fermentation process. The initial soluble solid contents in the berry juice were adjusted to 22 ºBrix before the fermentation. Alcoholic fermentation was conducted using Saccharomyces cerevisiae as the inoculant while Acetobacter pasteurianus was used for acetous fermentation. As observed for all samples during the alcoholic fermentation the levels of soluble solids decreased continuously and the levels of alcohol were found to increase at the end of fermentation process. Notably, the wine produced from ‘Blackberry’ species exhibited the highest levels of alcohol (11.73 %) while those produced from ‘Mulberry’ exhibited the highest levels of antioxidant activity (60.85 %). Similar results were observed for all samples during the acetous fermentation, in which the levels of alcohol dropped continuously and the levels of acetic acid were noted to elevate at the end of the fermentation process. The highest levels of acetic acid (5.01 %) was detected in the vinegars produced from ‘Cranberry’ species while those produced form ‘Raspberry’ species exhibited the highest levels of antioxidant activity (74.43 %). Sensory evaluation based on the 9-point hedonic scales showed that the vinegars produced from ‘Mulberry’ species displayed the highest overall acceptability with an average score of 7.27, equivalent to the hedonic scale of 9, which indicated the moderately pleasant levels of the vinegar preference of the consumers.

Enhanced growth rate and ulvan yield of Ulva pertusa using light-emitting diodes (LEDs)

Light-emitting diode (LED) technology offers potential energy-efficient light sources for algal aquaculture. In this study, the growth rate and ulvan yield of Ulva pertusa used for broad commercial applications were enhanced in vitro. To investigate the response of Ulva to LEDs, algae were grown under white fluorescent, pure primary color LED, and mixed LED lights for 28 days. Ulva sp. under blue LED and white fluorescent light showed higher specific growth rate (SGR, 12% day−1) than other light sources, while the growth under mixed red-blue LED light was lower than that under white fluorescent lighting. Despite the differences in alga growth under LEDs and white fluorescent light, few differences are observed in N and P content among algae grown under any light source. U. pertusa showed tissue nitrogen and ulvan contents in the ranges of 4.4–6.7% and 20.4–25.1%, respectively, under all LED light treatments. The ulvan extracted from algae under blue LED showed high levels of antioxidant activity measured with 2,2-diphenylpicrylhydrazyl (DPPH) radical and hydrogen peroxide. Moreover, the ulvan obtained under different lights showed different monosaccharide compositions. Based on these results, LEDs should be considered as the main light sources for indoor seaweed cultivation.

1H NMR combined with chemometrics tools for rapid characterization of edible oils and their biological properties

1H NMR spectroscopy was used to characterize seventeen Brazilian plant oils from different botanical origins and to determine the total phenolic content, as well as the antioxidant and antimicrobial activity. A profiling approach based on NMR and PCA revealed that the phenolic compounds signals (tangeretin, nobiletin and demethylnobiletin), as well as limonene, play an important role in the discrimination of the edible oils of tangerine (conventional and organic). Ricinolenic acid was responsible for the grouping of castor oil and the distinguishing other oils that can be characterized by the presence of fatty acids. In addition, polyaltic acid and kaurenoic acid were detected in the copaíba oil but were not observed in the other oils. The organic tangerine oil showed the highest content of total phenolic compounds and the highest level of antioxidant activity in relation to DPPH and ABTS. Most of the tested oils showed antimicrobial activity in relation to S. Typhimurium and S. Enteritidis, in a way that the buriti and the golden flaxseed organic oils displayed the highest activity, respectively. However, S. aureus, L. monocytogenes, and B. cereus demonstrated resistance to most of the tested oils. These findings may help in the understanding of edible oils and also how to check their quality based on analytical and biological approaches.

Coumestrol Confers Partial Resistance in Soybean Plants Against Cercospora Leaf Blight.

Although previous research showed that the purple symptom of Cercospora leaf blight (CLB) is associated with lower biomass of Cercospora cf. flagellaris and lower concentrations of cercosporin, a reactive oxygen species producer, as compared with blighted leaves, the hypothesis that the purple symptom is a plant reaction to the pathogen has never been tested. In this study, we demonstrated that high levels of coumestrol (COU) were associated with purple symptoms of CLB and that COU has strong antioxidant activity. Additionally, we found that COU is restricted to the pigmented areas of purple leaves, and the pigmentation is restricted to the adaxial surfaces, suggesting that COU may be acting as a sunscreen. Even though COU is associated with the purple leaf symptom, this coumestan is not the direct cause of discoloration in that COU is colorless. Quantification of chlorophyll a and b and total carotenoids suggested that blighted but not purple or asymptomatic leaves were undergoing photooxidative stress. Because the purple symptom is associated with high COU concentrations, lower biomass of C. cf. flagellaris, and lower cercosporin concentrations, we conclude that the purple symptom is a disease resistance reaction, mediated in part by COU, which provides a high level of antioxidant activity and, hence, partial resistance.