Presence Of Antioxidant Compounds Research Articles

Antibacterial and electrochemical activities of silver, gold, and palladium nanoparticles dispersed amorphous carbon composites

Gold (Au), silver (Ag), and palladium (Pd) nanoparticles (NPs) dispersed amorphous carbon composites have been prepared successfully by Green synthesis method using the reducing agent extracted from Cissus quadrangularis stem (CQS). The presence of antioxidant compounds in CQS extract is responsible for reducing and capping metal nanoparticles. The synthesized nanocomposites exhibit excellent antibacterial activity against gram-negative bacterial strains. Electrochemical performance of the composites is evaluated in symmetric two-electrode configuration. At a power density of 1 kW kg−1, the symmetric supercapacitor based on Au nanoparticle dispersed carbon electrodes exhibits an energy density of 7.1 Wh kg−1.

Effects of chlorogenic acid, epicatechin gallate, and quercetin on mucin expression and secretion in the Caco-2/HT29-MTX cell model.

Mucins are a family of large glycoproteins that represent the major structural components of the mucus and are encoded by 20 different mucin genes. Mucin expression can be modulated by different stimuli. In this study, we analyzed four mucins (MUC2, MUC3, MUC13, and MUC17) in coculture of Caco‐2/HT29‐MTX cells to demonstrate the variation in gene expression in the presence of antioxidant compounds like chlorogenic acid, epicatechin gallate, and quercetin (apple, tea, and coffee polyphenols, respectively). coculture of Caco‐2/HT29‐MTX cells was treated with polyphenols, and the expression of four mucins was determined by reverse‐transcriptase PCR. In addition, the secretion levels of MUC2 were established by enzyme‐linked immunoassay (ELISA) analysis. The results showed that each polyphenol compound induces different expression patterns of the mucin genes. Statistically significant up‐regulation of MUC17 was observed following incubation with epicatechin gallate and quercetin. ELISA results did not prove any significant differences in protein levels of MUC2 after treatment by the polyphenol compounds. The polyphenols considered in this study may influence mucin secretion and act on diverse salivary substrates to change the barrier properties of mucins for mucus secretion in different ways.

Pathophysiology and Urinary System Cancer: An Overview of the most important Herbal Plants and Natural Antioxidants on Kidney and Bladder Disorders

After diabetes and hypertension, urinary tract and kidney diseases and glomerulonephritis are a major cause of chronic kidney disease in developed countries. The use of medicinal plants can assist in the treatment and prevention of cancers and disorders of the urinary system and the kidneys, and various infections in the body due to the presence of antioxidant compounds, bioactive compounds, phenols, flavonoids, etc. These plants play the role of traditional medicine in the treatment and prevention of kidney diseases, kidney cancer, and other disorders of the urinary system. Some of the most important medicinal plants were addressed in this review for their effectiveness and mechanisms of actions. Based on the results obtained from the review of a number of articles indexed in certain databases such as Institute for Scientific Information, Scopus, PubMed, Google Scholar, etc., a number of plants have been reported to be effective in the treatment and prevention of urinary tract disorders and bladder and kidney cancers, including Equisetum arvense, Cornus mas L., Gynostemma pentaphyllum, Lycium barbarum, Camellia sinensis, Panax ginseng, Liriope muscari, Nigella sativa Linn, Abelmoschus manihot, Astragalus membranaceus, Tripterygium wilfordii, Zingiber zerumbet, Pistacia vera, Terminalia chebula Retz, Paeonia lactiflorapall, Cornus officinalis, Senna auriculata, Terminalia, Chebula, Opuntia megacantha, and Punica granatum. Pharmacological studies have addressed the therapeutic effects of medicinal plants, their clinical effects, and the use of their active ingredients for the production of natural, useful drugs. The phytochemical studies on these plants have shown that the most important compounds of these plants include total flavonoids and phenolics, steroids, quercetin, terchebi, luteolin, tannic acid, luteic acid, terflavin B, tannins, etc. Due to the active ingredients and active flavonoids of these plants, they can be used in the production of natural drugs that are effective on urinary tract (kidney and bladder) disorders and cancers, and reduce the pain and suffering of the patients.

Eugenia uniflora L.: potential uses as a bioactive plant

ABSTRACT: Natural products extracted from plants have always played an important role in the discovery of bioactive substances. This work carried out a review of the literature on the bioactive activities of Eugenia uniflora L. (Surinam cherries), as a potential plant in the various uses, be it medicinal, antimicrobial, antioxidant, insecticide and protective. In the literature, studies were found to confirm the antibacterial activity of E. uniflora leaves extract on Streptococcus, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. The presence of antioxidant compounds as total phenolics, such as anthocyanins and flavonoids, induction in the protection of plants by phytoalexins, as well as insecticidal and anthelmintic effects by the use of the extract of the E. uniflora tree. Although these different potential biotics of E. uniflora have already been reported, further studies are still needed on the use of natural products extracted from E. uniflora for employment for different purposes.

In Vitro Evaluation of Secondary Metabolites: Characterization and Antimicrobial Activity of Manilkara zapota L. Seed Extract

In the present study, seed extracts were analysed for its effective biological activity. The seed extracts were primarily subjected to qualitative and quantitative phytochemical analysis and further preceded to techniques such as TLC and bioautography to determine the active compounds through spot specification. The active compounds were further premeditated by GC–MS and FT-IR methods for antimicrobial analysis by agar well diffusion assay against few human pathogens including multidrug resistant phenotypes. The acetone extract of M. Zapota seeds revealed the presence of a significant number of secondary metabolites that ascertained that the plant possesses a rich group of bioactive compounds. The extract was quantified for its total phenolics (67.15 ± 4.35 mg/g), tannins (49.93 ± 8.76 mg/g) and flavonoids (60.06 ± 6.4 mg/g) respectively. GC–MS analysis exhibited the presence of 30 active compounds including both saturated and unsaturated fatty acids. FTIR analysis indicated 16 functional concrete structures of alkanes, alkenes, amines and aliphatic amines. Moreover, RF values calculated for the TLC spots along with the DPPH sprayed biography shows the presence of antioxidant compounds. Among the investigated microorganisms, Micrococcus luteus, Candida albicans and MRSA E-1122 strain exhibited the highest zone of inhibition. The present study provides convincing evidence that M. zapota seeds possess significant activity over human pathogens and MDR-MRSA by its active biocompounds present in the extract that helps to reduce oxidative stress by carrying off an antioxidant molecule that could be developed into therapeutic agents.

Sapucaia nut (Lecythis pisonis Cambess) and its by-products: A promising and underutilized source of bioactive compounds. Part I: Nutritional composition and lipid profile

The nutritional composition of the sapucaia nut, cake and shell, the nut and cake minerals content and the lipid profile of the nut oil (fatty acids, tocopherols, phytosterols and triacylglycerols) were determined. The nuts and cake exhibited a high content of lipid (47.9 to 60.8 mg 100 g−1), protein (15.8 to 19.5 mg 100 g−1), dietary fiber (16.5 to 22.6 mg 100 g−1) and provided an excellent source of selenium (26.4 to 46.94 μg g−1). The oil contained a high amount of unsaturated fatty acids (39.7 to 45.4% of oleic and 32.2 to 46.6% of linoleic acids) and presented a high Oxidative Stability Index (8.57–12.95 h) indicating the presence of antioxidant compounds in the oil. The major triacylglycerols in the sapucaia oil were LLO, PLO, LOO, POO, OOO, PLL and LLL. The main bioactive lipids identified in the oil were γ-tocopherol (19.2 to 28.5 mg 100 g−1) and β-sitosterol (92.8 to 194 mg 100 g−1). The results showed that the sapucaia nut and its by-products are a promising natural source of bioactive and nutritional compounds and when present in the diet can contribute to the maintenance of human health. In addition, the nut and by-product represents a promising raw material for the food industry.

Comparative Analysis of Ascorbic Acid Content and Antioxidant Activity of Some Fruit Juices in Syria

Fruits are considered essential constituents of a healthy diet. They possess antioxidant properties which can be attributed to the presence of antioxidant compounds. Ascorbic Acid (AA) is a water soluble antioxidant, abundant in fresh fruits and juices and considered as one of the most important contributors to the total antioxidant activity of fruits and vegetables. Two samples of the following fruit juices (orange, grapefruit, black mulberry, strawberry, pomegranate and tomato) were investigated for their AA content and total antioxidant activity. AA content was determined according to dichlorophenol indophenol method. Orange juice showed the highest results with amounts from 74.85mg/100 ml to 101.28mg/100 ml, while the lowest was pomegranate juice with amounts from 8.6mg/100 ml to 8.8mg/100 ml. Total antioxidant activity was subsequently determined using Ferric Reducing Antioxidant Power (FRAP) assay and reducing power assay. The results indicated that black mulberry juice had the highest antioxidant power, while tomato juice had the lowest. The study concluded that AA plays a dominant role as an antioxidant only in fruit juices which are known to be rich in AA. Other juices showed higher antioxidant activity which indicated the role of other antioxidant compounds i.e. phenolic compounds.

Phytochemical and pharmacological evaluation of ethanolic extract of Lepisanthes rubiginosa L. leaves

BackgroundThe current study was conducted to evaluate the antioxidant, analgesic, antihyperglycemic, neuropharmacological and antidiarrheal activities of ethanolic extract of Lepisanthes rubiginosa L. leaves in different experimental models.MethodsQuantitative and qualitative analysis were done by TLC (thin layer chromatography) and DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging assay. Analgesic, antihyperglycemic and antidiarrheal activities were evaluated using acetic acid induced writhing in mice, oral glucose tolerance test and castor oil induced diarrhea, respectively. Neuropharmacological activity was investigated in mice using both Open Field and Hole Board methods.ResultsTLC analysis indicated the presence of antioxidant compounds in the extract we used. The extract showed IC50 value was 31.62 μg/mL whereas the standard ascorbic acid showed 12.02 μg/mL. In acetic acid induced writhing assay, the extract showed 46.07% and 58.43% writhing inhibition at the doses of 250 mg/kg and 500 mg/kg body weight, respectively whereas standard diclofenac-Na (25 mg/kg) showed 86.52% writhing inhibition. The plant extract showed significant (p < 0.05) antihyperglycemic activity on mice as compared to control groups. In neuropharmacological activity assay the experimental animal showed a noticeable decrease in locomotion by showing a decrease in number of square crossed and head dipping at both doses (250 mg/kg & 500 mg/kg). In antidiarrheal activity test, the plant extract at the doses of 250 mg/kg and 500 mg/kg showed percent inhibition of defecation 57.89 and 77.19 respectively, whereas standard loperamide (3 mg/kg) showed percent inhibition of defecation 88.59.ConclusionThe results demonstrated that the extract has potential antioxidant, analgesic, antihyperglycemic, neuropharmacological and antidiarrheal activity.

Preliminary Phytochemical and Biological Screening of Cyclamen coum a Member of Palestinian Flora

Background: Since ancient times, the treatment of various diseases has relied on medicinal plants. The replacement of chemically synthesized drugs with natural medications gave the later advantageous due to their safety for humans. This study aimed to screen and to evaluate preliminarily phytoconstituents, total contents of flavonoids, tannins, and phenols also to evaluate the antibacterial and antioxidant activities of Cyclamen coum aerial parts methanol extract. Methods: Screening of phytoconstituents, total flavonoids, tannins and phenols contents, as well as antioxidant properties, were investigated for the Cyclamen coum aerial parts by using standard phytochemical and analytical methods. Evaluation of antibacterial activity of the plant methanolic extract was performed by using broth microdilution method. American Type Culture Collections of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Methicillin-Resistant Staphylococcus aureus (MRSA) were utilized to evaluate antibacterial activity. Results: Preliminary phytochemical qualitative analysis of the plant methanolic extract showed that the plant aerial parts contained amino acids, reducing sugar, carbohydrate, tannin, flavonoid, phenol, saponin, cardiac glycoside, and steroids. Total flavonoids, phenols, and tannins in plant methanolic extract were 60.88 mg QUE/g, 32.7 mg GAE/g and 11.7 mg CAE/g, respectively. Meanwhile, the antioxidant activity was estimated to be 31 µg/mL and has very weak antibacterial activity on the studied pathogens. Conclusion: In the present study, evaluation of total phenolic, tannins and flavonoid content from the aerial parts of C. coum can be an antioxidant naturally potent source. The results of in-vitro antibacterial studies showed that the studied plant has very weak antibacterial activity. In addition, the presence of antioxidant compounds in C. coum makes it a good candidate for manufacturing dietary supplements and food preservatives.

Estimation of Total Antioxidant Capacity of Hydroalcoholic Extract from the Matricaria Ineora By an Electrochemical Method

Plants have been used as medicines for thousands of years. They have been applied for the preparation of ingredients and drugs in the treatment of diseases [1-4]. Clinical studies revealed that a diet rich in fruits and vegetables decreased risk of cardiovascular diseases and cancers. These beneficial health effects have emanated from the presence of antioxidant compounds in the plants. Oxidation is one of the most important chemical and biochemical processes. Free radicals can oxidize nucleic acids, proteins and lipids, initiating degenerative diseases. Antioxidants such as phenolic compounds are compounds known to react with free oxygen radicals and thus preventing their cell-damaging action. Therefore, screening for antioxidant properties of plant extracts is prominent in their pharmaceutical applications. Different methods have been reported for the evaluation of antioxidant capacity of medicinal plant extracts. In the present research cyclic voltammetry have been used for antioxidant screening of medicinal plant extracts. Since, electrochemical techniques are low-cost and enable rapid analysis of sample. Cyclic voltammetry on carbon nanotube modified electrode appears to be a suitable tool in antioxidant assays. It can provide information about the number of compounds redox states and the stability of these states [5]. In this work, leaves of matricaria ineora, as a medicinal plant, were dried at shadow and at room temperature. The 3.0 g powdered leaves of the plant were macerated with 50 mL of ethanol:water (20:80) for 24 h and sonicated for 12 min. The extracts were filtered using filter paper. The voltammograms were obtained for electrochemical oxidation of antioxidant compounds on the bare and modified electrodes in two separate experiments in buffer solution (pH 7.2). It have been compared the cyclic voltammograms of matricaria ineora extract at a bare and single-walled carbon nanotube (SWCNT) modified glassy carbon electrodes. The cyclic voltammetric responses for electrochemical oxidation of extract on the bare electrode containing one pair redox peak and modified electrode containing two pair redox peaks at 100 mV/s. The peak current increased significantly on the SWNTs modified electrode as compared with the bare electrode. The electrode surface modification with SWCNTs augmented its effective surface area and the oxidation currents of antioxidants. The first redox peaks are related to compounds which also were oxidized on the bare glassy carbon electrode. Second peaks are related to compounds which cannot oxidize on the bare electrode but due to nanotubes electrocatalysis property oxidized them on the modified electrode.

Mild salt stress improves strawberry fruit quality

Strawberry is one of the most popular fruits because of its shape, color and taste, and the presence of antioxidant compounds. Because severe abiotic stresses result in detrimental consequences to plant growth, the effect of cultivating under mild stress conditions has rarely been investigated. Therefore, we evaluated the effect of mild salt stress on yield and quality of strawberry fruit. Mild salt stress did not affect yield. The lower level of mild salt stress evaluated showed increased vegetative growth (24%), higher photosynthetic effectiveness, and increased activity of phenoloxidase (22%) and polyphenoloxidase (33%), as well as the accumulation of sucrose (5%) and anthocyanins (60%) in the fruit, compared to non-stressed plants. The higher level of mild salt stress increased root growth (30%), the activity of phenylalanine ammonia lyase (68%), and the accumulation of total phenolic compounds (14%), and total antioxidant activity (13%) in the fruit, compared to non-stressed plants. The only phenolic compound improved in these treatments was (+)- catechins. Both levels of salt stress affected the expression of genes involved in the phenylpropanoid and flavonoid pathways, cell wall disassembly and abscisic acid-related genes. Therefore, mild salt stress improves strawberry fruit quality.

Programmable flow system for automation of oxygen radical absorbance capacity assay using pyrogallol red for estimation of antioxidant reactivity

An automated oxygen radical absorbance capacity (ORAC) method based on programmable flow injection analysis was developed for the assessment of antioxidant reactivity. The method relies on real time spectrophotometric monitoring (540nm) of pyrogallol red (PGR) bleaching mediated by peroxyl radicals in the presence of antioxidant compounds within the first minute of reaction, providing information about their initial reactivity against this type of radicals. The ORAC-PGR assay under programmable flow format affords a strict control of reaction conditions namely reagent mixing, temperature and reaction timing, which are critical parameters for in situ generation of peroxyl radical from 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH).The influence of reagent concentrations and programmable flow conditions on reaction development was studied, with application of 37.5µM of PGR and 125mM of AAPH in the flow cell, guaranteeing first order kinetics towards peroxyl radicals and pseudo-zero order towards PGR. Peroxyl-scavenging reactivity of antioxidants, bioactive compounds and phenolic-rich beverages was estimated employing the proposed methodology. Recovery assays using synthetic saliva provided values of 90±5% for reduced glutathione. Detection limit calculated using the standard antioxidant compound Trolox was 8μM. RSD values were <3.4 and <4.9%, for intra and inter-assay precision, respectively. Compared to previous batch automated ORAC assays, the developed system also accounted for high sampling frequency (29h−1), low operating costs and low generation of waste.

Phytochemical fingerprints combined with bioautographic enzyme inhibition and antitumor activity of Verbascum (Scrophulariaceae) and Ajuga (Lamiaceae) plant extractives on skin squamous cell carcinoma

The genera Verbascum and Ajuga with multiple traditional therapeutical uses are rich in phenolic compounds with potential anti-inflammatory, antioxidant and immunomodulatory properties [1]. The aim of this study was to screen the phytochemical and biological potential of the species V. nigrum L. and A. chia Schreb. for prevention and treatment of nonmelanoma skin cancer as part of a joint research project on multitarget activity of plant extract [2]. Methanol (MeOH) extraction of the aerial parts of A. chia and V. nigrum was followed by fractionation by RP-C18 flash chromatography. The phytochemical characterization was assessed by UPLC-DAD-ESI-MS and HPTLC. The latter was linked to (bio)autographic acetylcholinesterase inhibition and DPPH assays. Cytotoxic evaluation of HaCaT and A431 cells treated with extracts and fractions was done by MTT assay, followed by immunofluorescence microscopy. V. nigrum extract contains potential AchE inhibitors. Both plants show presence of antioxidant compounds. Based on UV and MS data we identified for A. chia with high probability luteolin-7-O-glucoside, apigenin and verbascoside and for V. nigrum, verbascoside, harpagoside and possible aucubin derivatives. V. nigrum extract, 100% MeOH and 50% MeOH fractions induced A431 cell apoptosis and decreased the cell invasion. The A. chia extract did not exhibit any cytotoxicity on A431 cell line. None of extracts exhibited cytotoxicity on HaCaT cells. Acknowledgements: Sciex-HMSch CRUS Switzerland No. 13.218 & N. Ciocirlan and V. Ghendov for plant material identification (Botanical Garden of Academy of Sciences of Moldova).

Nectandra falcifolia: potential phytopharmaceutical for skin damage protection designed by statistical approach and characterized by photoacoustic spectroscopy

Phytopharmaceutical products are being used in the treatment and prevention of health problems. Nowadays, the development and evaluation of novel pharmaceutical products is expensive and time consuming. A statistical approach is a good tool for optimal development processes. Nectandra falcifolia (Nees) J.A. Castigl. ex Mart. Crov. & Piccinini, Lauraceae, a Brazilian species, is reported as anti-inflammatory, anti-leishmanial and anti-microbial. However, there is little known about its chemical composition. For other species of Nectandra genus, the presence of antioxidant compounds is reported. In order to optimize the process of obtaining extract with high antioxidant activity, different extraction conditions were tested following a statistical approach. Two sequential experimental designs were used – first, a factorial 23 design, followed by central composite 22. The extracts manufactured by these experimental statistical matrixes had their antioxidant activity and phenolic contents quantified and the response surface plots were fitted in quadratic models and they predicted the best extraction condition for the best antioxidant activity. This standardized extract and its antioxidant activity were better evaluated by two complementary tests (ABTS and Burst respiratory). A topical formulation containing 1% (w/w) of standardized extract was prepared and used for an in vivo skin permeation study using a two-dose application. The photoacoustic spectroscopy was used to analyze the samples from the permeation study and the composition profile of standardized extract. In rat skin samples, the data demonstrated that for the higher dose of topical formulation (5g/cm2), the standardized extract could cross skin and be seen in epidermis and dermis. This was not the case for the lower dose (2g/cm2) which was only present in the epidermis. This information suggests that this novel standardized extract of N. falcifolia could be explored for skin damage prevention or treatment for diseases developed by oxidative damage.

Free radical scavenging ability of Aspalathus linearis in two in vitro models of diabetes and cancer

The free radical scavenging activity of Aspalathus linearis (Rooibos tea) and its effect on reactive oxygen species (ROS), catalase (CAT), and superoxide dismutase (SOD) were investigated in two in vitro disease models of cancer and diabetes. Although the antioxidant activity of this tea has been reported in several studies, its effects in disease models of ROS-induced oxidative stress have not been systematically evaluated to date. The oxygen radical absorbance capacity (ORAC) assay was used in this study to quantify the antioxidant capacity of the extract, whereas the ROS scavenging ability in hyperglycemia-induced human umbilical vein endothelial cells (HUVECs) and HeLa cells were investigated. The CAT and SOD assays were also carried out in the two disease models in order to evaluate the effect of the extract in the stimulation of these two enzyme activities. The extract was observed to have reduced ROS in a dose-dependent manner in both HUVECs and HeLa cells. The stimulation of the CAT and SOD enzyme activities were observed to be dose-dependent as well. The high ORAC value of the extract indicated the presence of antioxidant compounds which could directly quench ROS, whereby this mechanism of action could be hypothesized to have been further complemented through the stimulation of CAT and SOD. Overall, the Aspalathus linearis extract was observed to have increased the CAT and SOD activities in two in vitro disease models of cancer and hyperglycemia. Given the correlation between the ORAC values, the increases in CAT and SOD activities and the reduction in ROS in a dose-dependent manner, it could be hypothesized that the extract had a significant therapeutic potential for either the prevention of the onset of the two diseases or their progression because ROS has been identified as their root causes.

Campomanesia adamantium (Myrtaceae) fruits protect HEPG2 cells against carbon tetrachloride-induced toxicity

Campomanesia adamantium (Myrtaceae) is an antioxidant compounds-rich Brazilian fruit popularly known as gabiroba. In view of this, it was evaluated the hepatoprotective effects of pulp (GPE) or peel/seed (GPSE) hydroalcoholic extracts of gabiroba on injured liver-derived HepG2 cells by CCl4 (4mM). The results showed the presence of total phenolic in GPSE was (60%) higher when compared to GPE, associated with interesting antioxidant activity using DPPH assay. Additionally, HPLC chromatograms and thin layer chromatography of GPE and GPSE showed the presence of flavonoids. Pretreatment of HepG2 cells with GPE or GPSE (both at 800–1000μg/mL) significantly (p<0.0001) protected against cytotoxicity induced by CCl4. Additionally, the cells treated with both extracts (both at 1000μg/mL) showed normal morphology (general and nuclear) contrasting with apoptotic characteristics in the cells only exposed to CCl4. In these experiments, GPSE also was more effective than GPE. In addition, CCl4 induced a marked increase in AST (p<0.05) and ALT (p<0.0001) levels, while GPE or GPSE significantly (p<0.0001) reduced these levels, reaching values found in the control group. In conclusion, the results suggest that gabiroba fruits exert hepatoprotective effects on HepG2 cells against the CCl4-induced toxicity, probably, at least in part, associated with the presence of antioxidant compounds, especially flavonoids.

Changes in composition, antioxidant content, and antioxidant capacity of coffee pulp during the ensiling process

The objective of the present study was to determine the nutritive value, the presence of antioxidant compounds, and the antioxidant capacity of coffee pulp ensiled or non-ensiled. Dry matter (DM), crude protein (CP), ash, acid detergent fiber (ADF), neutral detergent fiber (NDF), and lignin, as well as the antioxidant compounds present in coffee pulp and their antioxidant capacity, were determined. A completely randomized design was used. Data were analyzed by analysis of variance. Ensiling of coffee pulp increased the CP content from 98.6 to 111.6 g kg−1 DM, NDF from 414.6 to 519.5 g kg−1 DM, ADF from 383.9 to 439.3 g kg−1 DM, and lignin from 122.9 to 133.6 g kg−1 DM. Caffeine decreased from 5.72 to 5.02 mg g−1 DM. Three antioxidant compounds were detected. Caffeic acid decreased due to ensiling (16.49 vs 14.69 mg g−1 DM). Gallic acid (2.88 vs 2.58 mg g−1 DM) and chlorogenic acid (62.12 vs 56.00 mg g−1 DM) did not differ, and there was similar antioxidant capacity of non-ensiled (215.66 µmol trolox g−1 DM) and ensiled coffee pulp (206.59 µmol trolox g−1 DM). Despite the decrease in the caffeic acid content due to the ensiling process, it is possible to use either ensiled or non-ensiled coffee pulp for animal feeding because of its high antioxidant capacity.

Evaluation of the total antioxidant capacity and antioxidant compounds of different solvent extracts of Chilgoza pine nuts (Pinus gerardiana)

The total antioxidant capacity of Pinus gerardania, or Chilgoza and the presence of antioxidant compounds which typically exist in pine nuts were quantified. Oxygen radical absorbance capacity assay, ferric reducing antioxidant power, and the 2, 2-diphenyl-1-picrylhydrazyl (DPPH•) and 2, 2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+) radical cation scavenging assays were conducted on dichloromethane, ethanol, ethyl acetate, hexane, methanol and water extracts of Chilgoza. The water and dichloromethane extracts displayed the highest antioxidant activity across all assays. Antioxidant compounds such as gallocatechin, catechin, lutein, lycopene, caretenoids and tocopherols were present in all extracts. Gallocatechin had the highest presence out of all the compounds. Its amounts present in the water and dichloromethane extracts were 64.9 and 56.9 µg per gram fresh weight (µg/g), respectively. The total carotenoid contents in the water and dichloromethane extracts were 14.72 and 14.26 µg/g, respectively, while the total tocopherol contents were 1.05 and 2.53 µg/g, respectively.

Reactive oxygen species, abscisic acid and ethylene interact to regulate sunflower seed germination.

Sunflower (Helianthus annuus L.) seed dormancy is regulated by reactive oxygen species (ROS) and can be alleviated by incubating dormant embryos in the presence of methylviologen (MV), a ROS-generating compound. Ethylene alleviates sunflower seed dormancy whereas abscisic acid (ABA) represses germination. The purposes of this study were to identify the molecular basis of ROS effect on seed germination and to investigate their possible relationship with hormone signalling pathways. Ethylene treatment provoked ROS generation in embryonic axis whereas ABA had no effect on their production. The beneficial effect of ethylene on germination was lowered in the presence of antioxidant compounds, and MV suppressed the inhibitory effect of ABA. MV treatment did not alter significantly ethylene nor ABA production during seed imbibition. Microarray analysis showed that MV treatment triggered differential expression of 120 probe sets (59 more abundant and 61 less abundant genes), and most of the identified transcripts were related to cell signalling components. Many transcripts less represented in MV-treated seeds were involved in ABA signalling, thus suggesting an interaction between ROS and ABA signalling pathways at the transcriptional level. Altogether, these results shed new light on the crosstalk between ROS and plant hormones in seed germination.

Influence of drying method and extraction variables on the antioxidant properties of persimmon leaves

Abstract The presence of antioxidant compounds and therefore the antioxidant capacity of persimmon leaves and their extracts have been reported by many authors. Furthermore, it is known that both the method of drying and the temperature at which this process takes place substantially affect the properties of the final product. However, there are no studies in the literature that examine how drying variables can affect the quality of persimmon leaves, especially as refers to preservation of their antioxidant properties. Therefore, the aim of this paper was to compare some antioxidant properties of aqueous extracts of persimmon leaves obtained under different drying methods (shade drying, hot air drying at 100 and 180 °C, and freeze drying) and infusion conditions (70, 80 and 90 °C for 1, 3, 5, 60 and 1440 min). The results in terms of total phenol content, flavonoids and antioxidant capacity indicated that air drying at 100 °C would be the optimal process for the stabilization of persimmon leaves, and their subsequent use in brewed beverages. Likewise, the best conditions of aqueous extraction in order to maximize the extractability of antioxidant compounds corresponded to 90 °C for 60 min. A short experiment performed in this study confirmed that small persimmon leaves (axial axis: 9±1 (cm); equatorial axis: 7.0±0.9 (cm)) had around 9% more flavonoids, and 7% more total phenolic content and antioxidant capacity than the large ones (axial axis: 17±2 (cm); equatorial axis: 10±1 (cm)).