Relative Antioxidant Activity Research Articles

Antioxidant and Antibacterial Activity of Nepeta × faassenii Bergmans ex Stearn Essential Oil

This study was designed to evaluate, for the first time, the antioxidant and antimicrobial activities of Nepeta × faassenii essential oil (NEO). Twenty-six compounds were identified by gas chromatography and mass spectrometry analysis, of which 4a alpha,7alpha,7a alpha-nepetalactone (34.12%), elemol (23.23%), spiro(5,6)dodecane (13.73%), and 3,4 alpha-dihydro-4a alpha, 7 alpha, 7a alpha-nepetalactone (7.93%) were the major compounds. The NEO exhibited broad-spectrum antibacterial effects, and possesses potent antifungal activity on Candida albicans and Candida parapsilosis. NEO’s antioxidant activity was evaluated against cold-pressed sunflowers oil by peroxide, thiobarbituric acid, 1,1-diphenyl- 2-picrylhydrazyl radical, and β-carotene/linoleic acid bleaching methods. The NEO showed strong scavenging (IC50: 0.032 ± 0.005 mg/mL) and relative antioxidative activity (RAA%: 92.31 ± 0.17%) in 1,1-diphenyl- 2-picrylhydrazyl radical and β-carotene/linoleic acid bleaching assays, respectively. Moreover, during 24 days of the incubation period, the oil inhibits the primary lipid oxidation significantly better (p < 0.05) than butylated hydroxyanisole (BHA). In the case of secondary lipid oxidation, the oil performed significantly better (p < 0.001) than BHA from day 8 to day 12 of the incubation period. The biological activities recorded suggest that NEO may represent an antioxidant and antimicrobial agent with applications in medicine or the food industry.

Structure–antioxidant activity relationships in boldine and glaucine: a DFT study

DFT calculations indicate that boldine and glaucine exhibit direct antioxidant activity through the HAT and SPLET (at high pH values) mechanisms.

Biochemical responses of Moringa oleifera Lam. plants to graded moisture deficit

Continual water loss through transpiration and evaporation as a result of drought leads to stomatal closure and subsequently the overproduction of reactive oxygen species (ROS) which causes oxidative stress in plants. A set of biochemical mechanisms are concurrently triggered to set in motion a defence line, which, among others, involves the synthesis of antioxidant and osmoprotectants compounds. These play a protective role to overcome stress. The objective of this study was to evaluate the effect of varying moisture regimes on the accumulation patterns and concentration of phenolic compounds, antioxidant activity and osmolyte proline in Moringa oleifera. The study was conducted in a greenhouse (25 ± 3°C) at ARC, Roodeplaat in Pretoria, South Africa. Moringa oleifera seeds were individually planted in pots using hygro-mix as the growth media. The experiment was laid out in a completely randomised design with four watering regimes of 100%, 75%, 50% and 35% field water capacity (FWC) each with 50 replicate plants. Proline content increased with the severity of moisture stress in all plant parts (root, stem and leaf), with the leaves under severe stress (35% FWC) recording the highest concentration. Folin C, aluminium chloride and butanol-HCL assays were used to determine total phenolic, flavonoid and condensed tannin concentrations, respectively, in the different plant parts at different growth stages and harvests. The concentrations of these secondary metabolites were consistently higher in leaves and increased with an increase in moisture stress. The highest concentrations were recorded in the second harvest under severe stress (35% FWC) for total phenolics and proanthocyanidins at 50% FWC for flavonoids . Leaves showed a better antioxidant ability and antioxidant activities increased with drought progression as determined by FRAP while DPPH radical scavenging and the β-carotene-linoleic acid model system did not show a distinct trend in antioxidant activities in relation to the different moisture levels. Based on the results of this study, antioxidant and osmoprotectant compounds as well as antioxidant activity appears to increase corresponding to severity of moisture stress in all plant parts at both harvests. This trend suggests that M. oleifera employs these mechanisms in adapting to moisture stress.

Multiple wavelengths maximization fusion fingerprint profiling for quality evaluation of compound liquorice tablets and related antioxidant activity analysis

With natural plant entering a worldwide new arena in clinical medicine and pharmaceutical, herbal preparation are becoming popular all over the world. Compound liquorice tablets (CLQTs) have been widely applied as effective and typical antitussive, expectorant and antiasthma. It is worth noting that quality determines effectiveness and safety, which make it essential for quality control of CLQTs. Considering the different UV absorption characteristics of various components, high-performance liquid chromatography fingerprint of 156 batches of CLQTs were determined at four wavelengths. Additionally, multi-wavelength maximization fusion profiling was developed to digest and synthesize the valuable fingerprint information of each sample for its holistic quality evaluation. Quantitative determination of five major ingredients was performed and no significant differences were found in five-compound content among 156 samples (p > 0.05). All samples were clarified into six quality grades using systematic quantified fingerprint method from qualitative and quantitative perspective and showed significant difference among nine manufactures (p < 0.05). A well established 2,2-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and diphenyl-1-picrylhydrazyl (DPPH) scavenging assay was applied to study the in vitro antioxidant activity of CLQTs samples using L-ascorbic acid as positive control. Furthermore, OPLS was established for the fingerprint-efficacy relationship analysis and demonstrated the significant contribution of peaks 15-liquiritin and 30-glycyrrhizic acid (VIP > 0.5). The study suggested that this quantitative fingerprint approach is reliable and beneficial for quality control of complex herbal medicine or herbal preparation.

Antioxidant and Anti-Inflammatory Activities in Relation to the Flavonoids Composition of Pepper (Capsicum annuum L.).

The chili pepper (Capsicum annuum L.) is a food source that is rich in flavonoids such as luteolin and apigenin. Flavonoids are known to have anti-inflammatory and antioxidant activities; however, studies on the flavonoids composition identified and the anti-inflammatory and antioxidant effects in pepper leaves (PL) and fruits (PF) are insufficient. In the present study, we investigated the antioxidant and anti-inflammatory effects in vitro, and the flavonoids contents of the PL and PF. Pepper extracts showed radical scavenging activities and ameliorated the lipopolysaccharide (LPS)-stimulated inflammatory response by decreasing nitric oxide production and interluekin-6 and tumor necrosis factor alpha levels in RAW 264.7 cells, with more effective activities noted for PL than for PF. Furthermore, PL extracts markedly inhibited the LPS-induced production of reactive oxygen species accumulation. The flavonoid profile and content of pepper were dependent on the part, with PL showing higher total flavonoids than PF. In particular, the content of luteolin glycosides in PL was twice that in PF. Thus, PL may be useful to prevent oxidative stress and inflammation-related diseases.

Composition and Antioxidant Activity of the Essential Oil from Achillea moschata Wulfen Growing in Valchiavenna and Valmalenco (Italian Central Alps)

Achillea moschata Wulfen (Asteraceae) is an endemic species growing on the Alps and traditionally used in several medicinal remedies. For its aromatic properties, it is also collected for food purposes. Chemical content and biological activity of A. moschata oil are not extensively studied. We investigated whether the different lithological and geomorphological features of two alpine areas including Vallone dello Scerscen and Valle dei Ratti, located in the Sondrio Province (Northern Italy), can influence the essential oil (EO) composition and the related antioxidant activity of the respective A. moschata populations. The essential oils obtained by steam distillation from the dried aerial parts were investigated by GC/FID and GC/MS. Several compounds were identified belonging to different chemical classes, including monoterpenes and sesquiterpenes as the most abundant constituents, together with ketones, alcohols, phenols, acids and esters. A variation in the quantitative composition of several constituents was recorded in the two oils. The main constituents were camphor (23.4-34.2%), 1,8-cineole (9.8-16.4%), trans-tujone (3.6-13.4%), sesquicineole (3.5-5.8%), borneol (1.1-4.8%), -caryophyllene (2.7-4.4%) and myrcene (1.3-4.2%). Their antioxidant activity was measured in vitro by the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS⋅+) and 2,2-diphenyl-picryl hydrazyl (DPPH⋅) stable radical assays. The essential oils showed similar and significant scavenger effects, possibly due to the synergistic action of all components including compounds present in small quantities.

Physiological and biochemical studies of black gram (Vigna mungo (L.) Hepper) under polyethylene glycol induced drought stress

Black gram (Vigna mungo L. Hepper) is an important nutritious legume plant, the loess plateau with strong drought tolerance and broad adaptability. To understand the adaptation mechanism of black gram under simulatedlevels of drought (5, 10 and 20% PEG) stress, and the growth characteristics, physiological parameters including levels of chlorophyll content, reactive oxygen species, and antioxidant enzymes were measured and the changes were compared with control. The result showed the root and shoot length, chlorophyll content, relative water content, stomatal activity, electrolyte leakage, antioxidant, and histochemical activity were carried out for treated and control plants. Experimentally, the drought-induced black gram seedlings of fresh weight, dry weight, and relative water contents found to be decreased with increasing concentrations of PEG. However, the electrolyte leakage and biochemical components (MDA content), antioxidant enzymes (SOD, CAT, POX), isozyme band patterns and histochemical detection of ROS accumulation (H2O2 and O2•–) level also enhanced under drought stress. The electrolyte leakage and MDA content were raised at 60% and 20% of severe PEG treatment. ROS accumulation was increased in the PEG treatment when compared to control. Overall, the rapid, accurate, and strong physiological observations from the electrolyte leakage and histochemical detection suggest that modification or enhancement of the biochemical and antioxidant contents would be determine the growth of black gram under PEG induced drought stress.

Vacuum drying of sweet cherry: Artificial neural networks approach in process optimization

Sweet cherries were vacuum-dried and the process was optimized with relative antioxidant activity index (RACI), standard score (SS), and artificial neural network (ANN) approach. Investigated input parameters were drying temperature and pressure, while moisture content, water activity, total phenolic, flavonoid and anthocyanins content, and antioxidant activity (FRAP, DPPH, and ABTS test) were analyzed as output parameters. The obtained mean value of R2 (0.872) indicates that the ANN investigated in this research could be successfully applied for describing the sweet cherry vacuum drying in the range of temperatures from 50 to 70°C and of pressures from 20 to 200 mbar. The optimized sweet cherries vacuum-dried process presents significant support for the possibility toward application of vacuum drying for sweet cherries in industrial conditions. According to ANN results, it is possible to take any combination of input parameters and calculate the output parameters observed in this research. Practical applications In the framework of this research, the artificial neural network (ANN) were applied on sweet cherries vacuum drying and as a main result the optimized vacuum drying process was obtained. Such optimized process presents significant base for the possibility toward application of sweet cherries vacuum drying in industrial conditions. This is enabled, since according to ANN results obtained in this research it is possible to take any set of input vacuum drying parameters (T: 50–70°C and p: 20–200 mbar) and calculate the values of the output parameters (moisture content, water activity, total phenolic, flavonoid and monomeric anthocyanin content, and antioxidant activity) observed in this research.

Structure-Biological Activity Relationships of Extra-Virgin Olive Oil Phenolic Compounds: Health Properties and Bioavailability.

Extra-virgin olive oil is regarded as functional food since epidemiological studies and multidisciplinary research have reported convincing evidence that its intake affects beneficially one or more target functions in the body, improves health, and reduces the risk of disease. Its health properties have been related to the major and minor fractions of extra-virgin olive oil. Among olive oil chemical composition, the phenolic fraction has received considerable attention due to its bioactivity in different chronic diseases. The bioactivity of the phenolic compounds could be related to different properties such as antioxidant and anti-inflammatory, although the molecular mechanism of these compounds in relation to many diseases could have different cellular targets. The aim of this review is focused on the extra-virgin olive oil phenolic fraction with particular emphasis on (a) biosynthesis, chemical structure, and influence factors on the final extra-virgin olive oil phenolic composition; (b) structure–antioxidant activity relationships and other molecular mechanisms in relation to many diseases; (c) bioavailability and controlled delivery strategies; (d) alternative sources of olive biophenols. To achieve this goal, a comprehensive review was developed, with particular emphasis on in vitro and in vivo assays as well as clinical trials. This report provides an overview of extra-virgin olive oil phenolic compounds as a tool for functional food, nutraceutical, and pharmaceutical applications.

Synthesis and Antioxidant Activity Evaluation of Trolox Derivatives

To find potent antioxidants, 16 novel Trolox derivatives were designed and synthesized via a reduction and esterification reaction. The chemical structures were characterized by NMR and MS. Trolox derivatives were employed to explore the potential structure–antioxidant activity relationships using three different assays. The results revealed that some of the synthesized compounds exhibited stronger antioxidant activities than L-ascorbic acid and Trolox, which suggests such compounds warrant further study.

English

Vernonia amygdalina has been widely utilized in Ghana and other West African states for numerous parasitic infections, diabetes and some inflammatory conditions. In this study we evaluated the antipyretic and antimalarial properties as well as in vitro antioxidant activities of an ethanolic stem bark extract of V. amygdalina (VAE). The antipyretic effect of VAE was assessed using Baker&rsquo;s yeast-induced pyrexia and the antimalarial activities of plant extract against Plasmodium berghei-infected mice in the Peters 4-day suppressive test. The antioxidant activities of the stem bark extract were determined by DPPH radical scavenging and total phenol content assay. Phytochemical screening was carried out using standard methods. V. amygdalina (100-600 mg kg-1) dose related decreased the Baker&rsquo;s yeast-induced fever in young rats. Also, it exhibited a significant (F (5, 24) = 91.35, P &lt; 0.0001) anti-plasmodial activity in the mouse model. It caused a percentage suppression of 81.80 &plusmn; 3.76 at 600 mg kg-1and a relative antioxidant activity in the DPPH radical scavenging assay with an IC50 of 146.4 &plusmn; 2.31 &micro;gml-1 and a total phenol content of 345.7 &plusmn; 4.56 mg g-1 of gallic acid equivalence. Preliminary phytochemical screening showed that the extract contained tannins, reducing sugars, flavonoids, terpenoids and alkaloids. V. amygdalina hydroethanolic stem bark extract evoked promising antipyretic, anti-plasmodial and antioxidant effects. Key words: Vernonia amygdalina, pyrexia, malaria, antioxidants, Baker&rsquo;s Yeast, Plasmodium berghei. &nbsp;

Assessment of Antiplasmodial and Antioxidant Activities, Total Phenolics and Flavonoids Content, and Toxicological Profile of Cola millenii K. shum (Malvaceae)

Aims: This study was designed to assess antiplasmodial and antioxidant activities in relation to phytochemical contents and toxicological profile of crude extracts of Cola millenii leaves.&#x0D; Place and Duration of Study: The study was carried out from April 2015 to November 2018 at University of Abomey-Calavi, Laboratory of Biochemistry and Bioactives Natural Products and Laboratory of Infectious Vector-borne Diseases.&#x0D; Methodology: Phytochemical screening of aqueous and ethanolic crude extracts was performed using standard methods. Estimation of total phenolics contains (TPC) and total flavonoids contains (TFC) was done using colorimetric methods. Antioxidant activity was assessed in vitro by 2,2-diphenyl-1-picrylhydrazyl (DPPH) Radical-Scavenging, Reducing power, superoxide radical scavenging and Hydrogen peroxide scavenging assay. Antiplasmodial activity was investigated in vitro using both field isolate and laboratory 3D7 strains of P. falciparum using Plasmodium lactate dehydrogenase (pLDH) assay. Hemoglobin release was measured spectrophotometrically to assess hemolytic power. Acute oral toxicity of extracts was evaluated on rats according to OECD 423 guideline.&#x0D; Results: Flavonoids, anthraquinones, coumarins, and triterpenes were recorded in both extracts while tannins were recorded only in ethanolic extract. High TPC and TFC were recorded with ethanolic extract with significate difference (P &lt;0.01) when compared to aqueous extract. Ethanolic extract exhibited the highest parasite growth inhibition against both field isolate (41.62±1.78%) and 3D7 (45.89±1.66%) strains at 100 µg/mL. Both extracts exhibited strong antioxidant activity according to different methods used. Toxicological profile revealed no hemolytic effect on human red blood cells as well as acute toxicity signs in rats.&#x0D; Conclusion: This study demonstrated strong antioxidant and moderate antiplasmodial activities of C. millenii extracts without toxicity effect on rats and human erythrocytes. It would play an important role in malaria and oxidative damage control.

Synthesis and Herbicidal and Antioxidant Activity of a Series of Hetero- and Carbocyclic Derivatives of Monochloroacetic Acid

Monochloroacetic acid esters and amides containing carbo- and heterocycles and heterocyclic esters and amides derived from commercial aryloxyacetyl chlorides were synthesized. The structures of the compounds were confirmed by 1Н and 13С spectroscopy. The herbicidal activity of the substances was studied with respect to mono- and dicotyledonous plants. The relative antioxidant activity of the compounds was studied by recording the luminol-dependent chemiluminescence. The experimental data, on the whole, confirm that the development of herbicides containing acetal and gem-dichlorocyclopropane fragments is appropriate and promising.

Investigating the Level of Vitamin E, C and Superoxide Dismutase in Patients with Allergic Asthma and Allergic Asthma with Helminths Infection

The aim of this study was to investigate the relationship of antioxidant activity, vitamin E, vitamin C and superoxide dismutase with the severity of allergic asthma by estimating their level in the patients’ sera, as well as evaluating their association with the level of total and specific serum IgE in allergic asthmatics and allergic asthmatics with helminths infection. The study applied on 180 subjects divided into three groups, 100 patients with allergic asthma and 50 patients having allergic asthma with helminths infection. The group of patients included 50 males and 100 females age 15-60 years. The control group comprised of 30 healthy individuals, included 14 males and 16 females age range 16-60 years. For each participant, the medical history was considered; the total and specific IgE levels, vitamin E, vitamin C and superoxide dismutase levels were determined in the patient’s sera using ELISA technique. The present study has demonstrated an increased level in serum total IgE in the patients’ groups (allergic asthma group and allergic asthma with helminths) compare to the control group, mean 374.54 IU/mL; 472.24 IU/mL; 29.21 IU/mL respectively. The level differences among the three groups are highly significant when compared statistically

Characterization of the Gh4CL gene family reveals a role of Gh4CL7 in drought tolerance

BackgroundThe function of 4-coumarate-CoA ligases (4CL) under abiotic stresses has been studied in plants, however, limited is known about the 4CL genes in cotton (G. hirsutum L.) and their roles in response to drought stress.ResultsWe performed genome-wide identification of the 4CL genes in G. hirsutum and investigated the expression profiles of the identified genes in various cotton tissues and in response to stress conditions with an aim to identify 4CL gene(s) associated with drought tolerance. We identified 34 putative 4CL genes in G. hirsutum that were clustered into three classes. Genes of the same class usually share a similar gene structure and motif composition. Many cis-elements related to stress and phytohormone responses were found in the promoters of the Gh4CL genes. Of the 34 Gh4CL genes, 26 were induced by at least one abiotic stress and 10 (including Gh4CL7) were up-regulated under the polyethylene glycol (PEG) simulated drought stress conditions. Virus-induced gene silencing (VIGS) in cotton and overexpression (OE) in Arabidopsis thaliana were applied to investigate the biological function of Gh4CL7 in drought tolerance. The Gh4CL7-silencing cotton plants showed more sensitive to drought stress, probably due to decreased relative water content (RWC), chlorophyll content and antioxidative enzyme activity, increased stomatal aperture, and the contents of malondialdehyde (MDA) and hydrogen peroxide (H2O2). Arabidopsis lines overexpressing Gh4CL7, however, were more tolerant to drought treatment, which was associated with improved antioxidative enzyme activity, reduced accumulation of MDA and H2O2 and up-regulated stress-related genes under the drought stress conditions. In addition, compared to their respective controls, the Gh4CL7-silencing cotton plants and the Gh4CL7-overexpressing Arabidopsis lines had a ~ 20% reduction and a ~ 10% increase in lignin content, respectively. The expression levels of genes related to lignin biosynthesis, including PAL, CCoAOMT, COMT, CCR and CAD, were lower in Gh4CL7-silencing plants than in controls. Taken together, these results demonstrated that Gh4CL7 could positively respond to drought stress and therefore might be a candidate gene for improvement of drought tolerance in cotton.ConclusionWe characterized the 4CL gene family in upland cotton and revealed a role of Gh4CL7 in lignin biosynthesis and drought tolerance.

ANTIOXIDANT AND CYTOTOXIC ACTIVITY OF A SERIES OF O- AND S-CONTAINING MACROCYCLES

The significant interest in the search and study of antioxidants, both natural and synthetic, is explained by the possibility of preventing these harmful effects of free radicals in the human body. The similarity of macroheterocyclic derivatives to endogenous biomolecules makes them promising for research as antioxidant agents. By the interaction of 1,3-oxoheterocycloalkanes with ethyl 2-diazo-3-oxobutanoate, previously unexplored polyfunctional oxygen and sulfur-containing macroheterocycles are obtained. The relative antioxidant activity of new macroheterocycles in two model systems: generating active forms of oxygen and modulating lipid peroxidation reaction, was revealed active forms of oxygen and described by the method of recording luminol-dependent chemiluminescence lipid peroxidation reaction. The in vitro cytotoxic activity of the studied compounds was studied on Jurkat (human T-lymphoblastic leukemia cells), HepG2 (human liver carcinoma cells), HEK293 (human embryonic kidney cells) cell lines. The data obtained indicate practical significance. So, reagents 1-7 in the active forms of oxygen generating system have anti- and prooxidative properties, and in the system modeling lipid peroxidation reaction, they show only prooxidant activity. The influence of heterocycles 1–7 on the processes of free radical oxidation was determined by the intensity of the maximum flash (Imax, у.е.) and the luminosity of light (S, у.е.). Compounds with maximum anti- (4) and prooxidative (6) properties in the active forms of oxygen generating system and reagent 3 with the highest prooxidant activity in the lipid peroxidation reaction modeling system do not possess cytotoxic activity in vitro on cell lines HEK293 and HepG2 cultured in DMEM medium (Biolot, Russia), Jurkat in RPMI medium (Biolot, Russia) in the presence of 10% fetal calf serum (Invitrogen, USA), 2 mM L-glutamine and 50 μg / ml gentamicin sulfate.&#x0D;

Pomegranate peel methanolic-extract improves the shelf-life of edible-oils under accelerated oxidation conditions.

Natural antioxidants extracted from agri‐waste resources have gained increased economic, sustainable, and health attention due to their sustainability, safer food‐applications, and beneficial components. Pomegranate peel extracts (Punica Granatum L.) have natural phytochemicals with superior protective effects stabilizing a variety of the most common vegetable oils consumed globally. Among five different pomegranate peel extracts, methanolic extract has maximum total phenolic content of 18.89%, a total flavonoid content of 13.95 mg QE kg−1, and a relative antioxidant activity of 93% when compared to other pomegranate peel extracts. Additionally, the HPLC analysis of pomegranate peel methanolic extract exhibited the maximum number of phenolic and flavonoid fractions. HPLC fractions showed that pyrogallol and ellagic acids were the most abundant phenolic compounds with 453 and 126 mg kg−1, respectively. In terms of flavonoid fractions, hesperidine and quercetrin were the highest detected‐flavonoids with about 50 and 35 mg kg−1, respectively, from HPLC flavonoids fractions. Therefore, pomegranate peel methanolic extract was selected at different concentrations (100, 200, 400, and 600 ppm) for the stabilizing experiment of Egyptian freshly refined edible oils (sunflower, soybean, and corn oils) in comparison with synthetic antioxidant (tert‐butyl hydroquinone TBHQ‐200 ppm) during accelerated storage at 70°C for 10 days. The results from the accelerated storage experiment indicated that pomegranate peel methanolic extract (at different concentrations: 200, 400, and 600 ppm) exhibited stronger antioxidant capability in all tested oils rather than negative controls (without antioxidant) and synthetic antioxidant TBHQ‐200. Under accelerated oxidation conditions, pomegranate peel methanolic extract have the potential capability to improve the shelf life of edible oils in comparison with the most powerful synthetic antioxidant (TBHQ‐200 ppm).

In Vitro Digestion of Chestnut and Quebracho Tannin Extracts: Antimicrobial Effect, Antioxidant Capacity and Cytomodulatory Activity in Swine Intestinal IPEC-J2 Cells.

Simple SummaryCastanea sativa Mill. (Fagaceae) is the predominant sweet chestnut tree in Europe. Despite the significant economic value of chestnuts as sources of food and wood, the high content of tannin also increases the value of sweet chestnut trees. Quebracho trees (Schinopsis spp., family Anacardiaceae) grow mainly in Argentina and Paraguay. Quebracho extract obtained from Schinopsis spp. contains 15% to 21% pure tannin. Tannins extracted from these plants have been applied in intensive swine farms due to their ability to improve animal performance and health. However, there are contrasting results regarding the bio-accessibility of chestnut and quebracho and their relative antioxidant activity and growth-rate reducing ability on E. coli, which ultimately affect their benefits in terms of intestinal health and animal production. Our results demonstrate that chestnut and quebracho exert a growth inhibitory activity against Enterotoxigenic E. coli (ETEC) species and antioxidant capacity directly, without extraction and after in vitro digestion. Our findings not only suggest that the combined use of chestnut and quebracho can maximize their functional effects, but also that an appropriate dosage of tannins may be key in terms of their effect on bacteria and cells.Quebracho (Qu) and chestnut (Ch) are natural sources of tannins and they are currently used in animal nutrition as feed ingredients. However, to date the bio-accessibility, antimicrobial, antioxidant, and intestinal epithelial cell stimulatory doses of Qu and Ch have not been determined. Our study investigates the antioxidant and E. coli F4+ and F18+ growth inhibitory activity of Qu, Ch, and their combinations after solubilization in water (to evaluate the already bio-accessible molecules) and after simulated gastro-intestinal digestion in vitro. The effect of an in vitro digested Ch and Qu combination was also tested on intestinal epithelial IPEC-J2 cells experimentally stressed with hydrogen peroxide (H2O2) and Dextran Sodium Sulfate (DSS). The results showed that undigested Qu and Ch alone, and in combination, exerted a valuable antioxidant capacity and E. coli F4+ and F18+ growth inhibitory activity. The concentration of 1200 µg/mL exhibited the highest E. coli growth inhibitory activity for all the samples tested. In addition, after in vitro digestion, Qu and Qu50%–Ch50% maintained E. coli growth inhibitory activity and a modest antioxidant capacity. Three hours pre-treatment with in vitro digested Qu50%–Ch50% counteracted the H2O2 and DSS experimentally-induced stress in the intestinal IPEC-J2 cells. Ch and Qu tannin extracts, particularly when combined, may exert E. coli F4+ and F18+ growth inhibitory activity and valuable antioxidant and cell viability modulation activities.

Proximate Composition, Physicochemical Properties and Antioxidant Activity of Flaxseed

Aims: The aims of this study were to investigate the proximate composition of flaxseed; physiochemical properties and antioxidant activity of flaxseed.&#x0D; Study Design: Using standard analytical methods to determine the proximate composition of flaxseed, extraction of flaxseed in different trials under the same conditions using two different solvents and investigating their physicochemical properties and antioxidant activity.&#x0D; Place and Duration of Study: This study was conducted in the laboratory of department of applied and industrial chemistry, International University of Africa, University of Medical Sciences and Technology and National Centre for Research, Khartoum – Sudan, during June 2019.&#x0D; Methodology: The prepared sample of flaxseeds was tested for proximate composition and then extracted with petroleum ether and n-hexane. The extracted oil was then subjected to physicochemical analysis, GC-MS analysis and antioxidant activity test.&#x0D; Results: The oil yield of flaxseed was high 21.95% and 28.29% with n-hexane and petroleum ether respectively. The results obtained for proximate composition were: moisture (8.50 ± 0.49%), ash (1.96 ± 0.00%), fiber (20.23 ± 3.47%), protein (21.00 ± 0.74%),fat (43.17 ± 0.99%) and carbohydrate (5.14 ± 2.73%).The physicochemical properties of n-hexane and petroleum ether extracted flaxseed oils were: density (0.92 ± 0.00 g/cm3), refractive index (1.47 ± 0.00 and 1.48 ± 0.01 at 28°C), acid value (0.76 ± 0.10 and 0.75 ± 0.20 mg KOH/g), peroxide value (4.67 ± 1.00 and 2.69 ± 0.55 meq O2/kg), saponification value (185.61 ± 0.56 and 187.83 ± 2.08 mg KOH/g oil), unsaponifiable matter (5.57 ± 0.64 and 2.83 ± 0.23 mg KOH/g oil) and iodine value (97.24 ± 0.86 and 97.44 ± 2.93 g/100 g) respectively. Statistical analysis showed no significant difference between the means of the two data sets of physicochemical properties of flaxseed oils extracted with the two solvents used at 95% confidence level. The GC-MS spectrum of flaxseed oil extracted with n-Hexane revealed presence of 27 fatty acids, the predominant were linoleic acid (46.53%), palmitic acid (18.04%), stearic acid (12.23%), linolenic acid (11.63%) and oleic acid (4.24%). While for petroleum ether extract a total of 28 fatty acids were identified the major were: linolenic acid (42.39%), linoleic acid (26.17%), palmitic acid (12.89%), stearic acid (10.73%) and methyl erucic (1.24%.). The oils also, showed good antioxidant activity in relation to control; 28 ± 0.09 (DPPH) for n-Hexane extract and 26 ± 0.05 (DPPH) for petroleum ether extract.&#x0D; Conclusion: Based on the results obtained flaxseed and flaxseed oil had good potential for human consumption and can be used for other application.

Lycopene Synthesis and Related Gene Expression in Pummelo Pulp Increased in Shade-grown Fruit

The effects of bagging-induced light reductions on lycopene synthesis and the expression of related genes, antioxidant activity, and sugar composition of ‘Tubtim Siam’ pummelo (Citrus maxima) were investigated. Glucose, ascorbic acid, and flavonoid concentrations and 2, 2-diphenyl-1-picryhydrazyl scavenging activity were decreased in fruit covered with bags while still on the tree [0.01 μmol·m−2·s−1 photosynthetic photon flux density (PPFD)] compared with the untreated control (596.7 μmol·m−2·s−1 PPFD). The bagging treatment significantly decreased the temperatures on the surface in the bag. In addition, the bagging treatment decreased abscisic acid concentrations in the peel and pulp. However, the bagging treatment increased lycopene concentrations, upregulated phytoene synthase (CsPSY) and ζ-carotene desaturase (CsZDS) gene expressions; downregulated chromoplast-specific lycopene cyclase (CsβLCY), β-carotene hydroxylase (CsβCHX), and ε-ring hydroxylase (CsɛCHX); and decreased 9-cis-epoxycarotenoid dioxygenase (CsNCED1) gene expressions in the pulp. It is possible that maintaining a temperature of ≈25 °C in fruit covered with bags may increase the lycopene concentration in the pulp with the upregulation of CsPSY and CsZDS and the downregulation of CsβLCY, CsβCHX, CsɛCHX, and CsNCED1 gene expressions in the pulp.