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The aim of this study was to determine the total polyphenol and flavonoid content, antioxidant properties and fatty acid profile of semi-hard goat cheese ripened in an oil mixture (Mljet's extra virgin olive oil and refined sunflower oil; 50:50) for different time periods. Five batches of cheese were produced, and each batch was divided into three groups: (1) ripening in air (control group), (2) ripening in oil after 10 days of air ripening, (3) ripening in oil after 20 days of air ripening. The cheeses were sampled on days 0, 10, 20, 30, 45 and 60 of ripening. On day 60, the total polyphenol and flavonoid content differed significantly (p<0.05, p<0.01, respectively) between the group 1 (control group) and group 3 as well as between groups 2 and 3. A significant difference (p<0.01) was found in antioxidant activity between the control group and group 3 with two spectrophotometric methods (DPPH - 2,2-diphenyl-1-picryl-hydrazyl; ABTS - 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)). The ripening treatment significantly (p<0.01) influenced the saturated (SFA) and unsaturated fatty acid (UFA) content between the oil-ripened cheeses. The prolonged air ripening prior to the immersion into oil in group 3 cheeses led to a greater water loss, and the formation of a cheese structure that allowed the oil to penetrate, resulting in a higher polyphenol and flavonoid content, antioxidant activity (DPPH) and UFA content (including oleic and linoleic acid) than in group 2. This indicates that the time of immersion influences the bioactive compounds in the cheese and thus, affects the nutritional value of the cheese. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agriculturae Slovenica is the property of Biotechnical Faculty of the University of Ljubljana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study targeted to determine the total phenolic content and antioxidant activity of essential oils Cinnamomum zeylanicum, Vitis vinifera, Allium cepa and Sesamum indicum. Total phenolic content was measured by Folin-Ciocalteu assays. The antioxidant potential of the tested extracts was evaluated using DPPH, CUPRAC and total antioxidant capacity (TAC) assays. The total phenolic compounds in essential oils varied widely, ranging from 80.26±0.007 μg GAE/mL to 268.20±0.008 μg GAE/mL. Cinnamon oil exhibited higher DPPH scavenging activity and CUPRAC activity. This study revealed that essential oils of C. zeylanicum, V. vinifera, A. cepa and S. indicum are good sources of natural antioxidants. [ABSTRACT FROM AUTHOR]

Žitna zrna, zlasti otrobi, so bogat vir fenolnih spojin z antioksidativnim delovanjem. Potencialni pozitivni učinki fenolnih spojin iz polnozrnatih zrn krušne pšenice (Triticum aestivum L.) in pire (Triticum spelta L.) na človeško zdravje so zaradi slabe biološke dostopnosti in razpoložljivosti vezanih fenolnih spojin omejeni. Študije so pokazale, da so biotehnološki procesi (kaljenje/fermentacija/encimsko tretiranje) učinkovita strategija za izboljšanje sproščanja vezanih fenolnih spojin iz matriksa celičnih sten žitnih zrn. V preglednem članku temeljito obravnavamo vplive biotehnoloških procesov na sestavo, antioksidativno aktivnost in biološko dostopnost fenolnih spojin iz zrn krušne pšenice in pire. Obstoječe raziskave kažejo na prisotnost raznovrstnih fenolnih spojin v zrnih krušne pšenice in pire, zaradi česar so polnozrnata žitna zrna odlična za uporabo v izdelkih, z namenom izboljšanja njihove hranilne vrednosti. Dokazano je, da biotehnološki procesi učinkovito povečajo vsebnost biološko dostopnih fenolnih spojin v žitnih zrnih, kar omogoča izboljšano in vitro antioksidativno delovanje. Trenutno primanjkuje in vivo študij za potrditev ugotovitev dobljenih in vitro, zato bodo v prihodnosti ključne in vivo študije določanja biološke aktivnosti fenolnih spojin iz predhodno obdelanih zrn.

The total phenolic content and antioxidant activity of wine and fermented pomace (FP) from Cabernet Sauvignon grapes harvested at the stage of full ripeness were evaluated by spectrophotometric analysis. Wine and pomace were obtained after prolonged maceration during spontaneous and inoculated fermentation of fully ripe grapes. Three individual vinifications were inoculated with the following commercial yeasts: BDX (Lallemand, Montréal, QC, Canada), FX10 (Laffort, Bordeaux, France) and Qa23 (Lallemand, Montréal, QC, Canada). For each vinification, maceration lasted 0, 3, 5, 7, 14 and 21 days, respectively. The total phenolic content was determined spectrophotometrically using the Folin-Ciocalteu method. Two different methods were used to evaluate the antioxidant activity of the wine and pomace samples: the Ferric Reducing Activity of Plasma (FRAP) and the Trolox Equivalent Antioxidant Capacity (TEAC). The use of a winemaking process that included different maceration times and inoculation with yeasts, as well as spontaneous fermentation, significantly modulated the total phenolic content of the obtained wines and FP. This study could provide a good basis for the practical application and obtaining wines with a high content of phenolic compounds and antioxidant properties. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Honey is a product of high nutritional value, used as a raw material for obtaining mead. However, adding fruit juices, including chokeberry juice, can improve mead quality. This paper aims to assess the effects that adding different quantities of chokeberry juice, with the variation of 3 amounts of inoculated yeast, has on the fermentation and physicochemical, antioxidant, and antimicrobial properties of mead. The parameters analyzed are the dry matter content, pH value, and content of volatile acids, ethanol and methanol, total phenols and flavonoids, FRAP, DPPH, and ABTS tests, and antimicrobial properties. The results obtained in this paper show that adding chokeberry juice improves the antioxidant properties of the final product and positively affects the course of mead fermentation, i.e., it has led to an increase in the maximum concentration of ethanol. Regarding the chemical composition of mead, there is no significant difference, except in the obtained ethanol content, which is the highest in samples with 10% of added chokeberry juice. Furthermore, the control sample showed the best antimicrobial activity, while the sample with 5% added chokeberry juice showed the weakest effect. Finally, the strongest effect was seen in the sample with 20% of added chokeberry juice. [ABSTRACT FROM AUTHOR]

Copyright of Botanica Serbica is the property of University of Belgrade, Institute of Botany & Botanical Garden Jevremovac and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botanica Serbica is the property of University of Belgrade, Institute of Botany & Botanical Garden Jevremovac and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Iako klasična proizvodnja bijelih vina podrazumijeva fermentaciju mošta, suvremeni trendovi podrazumijevaju proizvodnju bijelih vina uz maceraciju, odnosno fermentaciju masulja. Cilj ovog rada bio je utvrditi utjecaj duge maceracije grožđa na kakvoću vina 'Graševina'. Istraživanje je provedeno tijekom 2021. godine u vinogradima i vinskom podrumu Veleučilišta u Požegi u vinogorju Kutjevo. Nakon berbe, kontrolni uzorak vina proizveden je klasičnim postupkom proizvodnje bijelih vina, te su provedena dva tretmana duge maceracije u periodu od 3 mjeseca - jedan uz sulfitiranje tijekom primarne prerade a drugi bez sulfita. U vinima su analizirani osnovni parametri kakvoće, koncentracija jabučne i mliječne kiseline, optička gustoća pri 280 nm, ukupni fenoli i antioksidativna aktivnost DPPH metodom. Statistički značajna razlika zabilježena je kod ukupnih fenola, kao i antioksidativnoj aktivnosti, s najvećim vrijednostima u maceriranom uzorku uz primjenu SO2. Organoleptičko ocjenjivanje uzoraka proveli su certificirani ocjenjivači, metodom 100 bodova. Najveću prosječnu ocjenu od 87 bodova dobilo je vino proizvedeno dugom mareracijom grožđa uz redovito sulfitiranje. Kontrolni tretman slabije je ocijenjen, sa 72 boda. Vino proizvedeno dugom maceracijom bez korištenja sulfita ocjenjeno je sa 66 boda uz napomenu pojedinih ocjenjivača o izraženoj oksidaciji.

This work aimed to assess and compare the phytochemical composition, the free radical neutralization capacity, and antidiabetic potential of a traditional herbal mixture and its individual ingredients: Apium graveolens, Polygonum aviculare, Hypericum perforatum, and Conyza canadensis. Antioxidative capacity was evaluated using DPPH radical scavenging test. Antidiabetic activity was assessed using α-amylase inhibition assay. The results showed that there was a positive correlation between antioxidant and antidiabetic activity with total phenol (p < 0.001) and flavonoid content (p < 0.001) in all tested extracts. Herbal mixture had higher total phenol and flavonoid content than most of its individual ingredients. Its antioxidant capacity was excellent, even higher than standard, butylated hydroxytoluene (p < 0.001). Moreover, it showed significant antidiabetic potential (IC50 value 99.70±8.4 μg/ml). To conclude, the herbal mixture showed great potential for the future use as a dietary supplement in the therapy for diabetes. [ABSTRACT FROM AUTHOR]

Copyright of Acta Facultatis Medicae Naissensis is the property of Nis University, Faculty of Medicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The current study, we investigated phenolic content and antioxidant activity of ethyl acetate and dichloromethane extracts of thyme, turmeric, propolis and their mixtures. The highest and the lowest phenolic contents were found in ethyl acetate extract of propolis (214.94±0.023 μg GAE/mL) and dichloromethane extract of thyme (21.02±0.013 μg GAE/mL). Total antioxidant capacity of ethyl acetate extracts ranges from 127.15±0.031 μg AAE/mL and 232.2±0.028 μg AAE/mL; dichloromethane extracts ranges from 61.6±0.019 μg AAE/mL and 159.95±0.035 μg AAE/mL. CUPRAC activity and DPPH radical scavenging activity of ethyl acetate extracts are higher than dichloromethane extracts. According to the obtained results, it can be said that propolis, thyme and turmeric could be an alternative to synthetic antioxidants. [ABSTRACT FROM AUTHOR]

Enrichment of food is a strategy to reduce the incidence of deficiencies in micronutrients in a population. Couscous is widely consumed in Algeria, thus the objective of this study was to obtain an enriched couscous with enhanced therapeutic potencies and with good physicochemical, technological, and microbiological characteristics. Three mass ratios of the traditional preparation Issoufer (10, 20, and 30 %) were added to wheat couscous, and then compared with a control couscous made 100 % of semolina. A significant (p < 0.05) increase was noticed in the ash, proteins, lipids, carbohydrates, phenolic compounds, flavonoids, and anti-radical activity values, for all the mass ratios of Issoufer powder. In contrast, the moisture and pH-value revealed a significant (p < 0.05) decrease in Issoufer powder. The acute toxicity study revealed no lethal effects and behavioural signs of toxicity at the tested doses (100, 250, 500, and 750 mg kg−1) of the extract of Issoufer during the 5 days of observation. The results of antibacterial activity showed diameters of inhibition zones had achieved 29.90±0.60 mm. Based on obtained results, Issoufer powder can be considered a good ingredient to develop functional couscous naturally enriched of secondary metabolites, and can be used in the prevention of several diseases, as well as used in the food industry. [ABSTRACT FROM AUTHOR]

Copyright of Agriculture / Poljoprivreda is the property of Josip Juraj Strossmayer University of Osijek, Faculty of Agriculture in Osijek and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botanica Serbica is the property of University of Belgrade, Institute of Botany & Botanical Garden Jevremovac and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Glasnik Zastite Bilja is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the petals collected from peony hybrid Paeonia lactiflora "Bowl of Beauty" and Calendula officinalis L. were extracted using an ethanol-water mixture assisted with microwave and ultrasonic treatment. The isolation of Calendula officinalis L. essential oil was done by hydrodistillation as well. The total phenolic and flavonoids content in the extracts and oil were determined and their antioxidant activity was evaluated. The highest total phenolic content was found for the extracts of hybrid P. lactiflora and C. officinalis L. obtained by ultrasound extraction (83.16 and 114.47 mg GA/g, respectively), while the flavonoid content obtained by microwave-assisted extraction was relatively high (123.48 and 65.29 mg QE/g, respectively). The highest antioxidant activity was obtained in DPPH• and ABTS•+ assay for the microwave-assisted extraction of hybrid P. lactiflora (79% and 83%) and ultrasound-assisted extraction of C. officinalis L. (45% and 49%), respectively. To improve antioxidant activity of both types of examined analytes (extracts and essential oil), the pectin biopolymer film (as a carrier) was prepared in the process of enzymatically assisted catalysis. Optical microscopy and FTIR spectroscopy were used for the characterization of obtained materials. The films, with essential oil of C. officinalis L. and gallic acid, showed significantly increased percentage inhibition in DPPH• and ABTS•+ test (91% and 95%, respectively) after 10 minutes. The results, also, showed that all formulations of pectin biopolymer film, modified with gallic acid, can be successfully applied as a carrier for both types of ingredients. [ABSTRACT FROM AUTHOR]

Copyright of Pesticides & Phytomedicine / Pesticidi i Fitomedicina is the property of Institute of Pesticides & Environmental Protection and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Verbascum species are traditionally used in the treatment of respiratory disorders. Orange mullein (Verbascum phlomoides L.) is one of three species that are the official source of drug mullein flower (Verbasci flos). Our study aimed to determine the overall quality of the V. phlomoides flos and V. phlomoides folium, the contents of polyphenols, tannins, flavonoids, and phenylpropanoid derivatives alongside the antioxidant capacity of their ethanolic extracts. Quality control tests were conducted according to monographs of Ph. Eur. 10.0, secondary plant metabolites were quantified spectrophotometrically while the antioxidant potential was estimated by two complementary methods (DPPH free radical scavenging and β-carotene bleaching assay). The higher contents of examined compounds were determined in flower extract although the leaf extract showed a stronger antioxidant capacity. We can conclude that Verbascum phlomoides is a rich source of biologically valuable phenolics, it possesses considerable antioxidant capacity and investigated herbal drugs fulfill pharmacopeia's quality requirements. [ABSTRACT FROM AUTHOR]

Swiss chard (Beta vulgaris L. Subsp. Cicla) is a good source of different bioactive compounds highly used in different diets all over the world, especially in Mediterranean. The leaves and stems are edible parts used in traditional dishes. The aim of this study was to determine the effect of different food processing treatments on total phenolic content and antioxidant activity of Swiss chard using two methods of extraction. Total phenolic content of raw, boiled, and frozen Swiss chard was determined by Folin-Ciocalteu method. ABTS radical scavenging capacity assay and 1,1-diphenil-2-picrylhydrazyl assay (DPPH) were used to determine the antioxidant activity. The highest phenolic content and antioxidant activity was found in raw extracts of Swiss chard (34.47±3.67 mg GA/g DW). Freezing and boiling led to an equal reduction of total phenolic content of investigated samples. The antioxidant activity was not significantly affected by boiling procedure, while freezing led to decrease of the antioxidant activity of Swiss chard. [ABSTRACT FROM AUTHOR]

This paper evaluated antioxidant, antimicrobial and antibiofilm activities of ethanol, methanol, acetone and chloroform extracts of lignicolous fungal species Fomes fomentarius (L.) Fr. (Polypodiaceae). Antiradical activity was evaluated by using DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. The antimicrobial screening was carried out via disc diffusion and microdilution methods in order to estimate minimum inhibitory (MIC) and minimum bactericidal concentration (MBC) of analyzed extracts against seven standard bacteria and one yeast: Escherichia coli NRRL B-3704, Pseudomonas aeruginosa ATCC 27853, Proteus vulgaris ATCC 13315, Acinetobacter baumanii ATCC 19606, Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 25923, S. haemolyticus ATCC 43252 and Candida albicans ATCC 10231. In vitro antibiofilm activities were investigated based on crystal violet binding assay. All the extracts showed higher antioxidant activity compared to BHT (butylated hydroxytoluene) which was used as a standard. Ethanol, methanol and acetone extracts of the tested macrofungus also showed higher antimicrobial effect against P. aeruginosa ATCC 27853 in comparison to the antibiotic penicillin (P10). The lowest MIC was recorded by ethanol extract against S. haemolyticus ATCC 43252 (0.625 μg/mL). The highest antibiofilm activity was also noticed against biofilm formed by S. haemolyticus ATCC 43252. The results indicated that the F. fomentarius tested represent potential source of natural bioactive compounds with respect to antimicrobial, antibiofilm and antioxidant activities. [ABSTRACT FROM AUTHOR]

Copyright of Botanica Serbica is the property of University of Belgrade, Institute of Botany & Botanical Garden Jevremovac and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Milk-based kombucha beverages were obtained conducting kombucha lead fermentation of milk. In order to discriminate the analysed samples and to detect similarities or dissimilarities among them in the space of experimentally determined variables, hierarchical cluster analysis (HCA) and principal component analysis (PCA) were applied. Linear discriminant analysis (LDA) was conducted on the raw data set in order to find a rule for allocating a new sample of unknown origin to the correct group of samples. In the space of the variables analysed by HCA, the dominant discriminating factor for the studied samples of kombucha beverages is the milk fat (MF) content, followed by total unsaturated fatty acids content (TUFA), monounsaturated fatty acids content (MUFA) and polyunsaturated fatty acids content (PUFA). The samples with 0.8 and 1.6% milk fat belong to the same cluster in the space of the analysed variables due to similarities in their AADPPH. It was determined by LDA that there was the biggest difference in quality between the groups of products with winter savoury and stinging nettle, while the highest similarity is between groups of products with wild thyme and peppermint regarding their pH values and antioxidant activity expressed as AADPPH. [ABSTRACT FROM AUTHOR]

Introduction: Comprising of a unique combination of bioactive polyphenol compounds, grapes are shown to have a beneficial effect on the skin as well as the whole body. They exhibit high antioxidative and antiradical activity through mechanisms of heavy metals chelation, scavenging reactive oxygen species, inhibiting lipid peroxidation, and preserving the integrity of the cell membranes. In the winemaking industry, after crushing and pressing, grape pomace (stems, seeds, pulp, and skin) is removed as a by-product. This valuable source of bioactive compounds is often treated as animal food, compost, raw material in the brewery, but unfortunately mostly disposed of as unusable waste. Aim: The aim of this study was to compare redox properties of absolute EtOH, 50% EtOH, and H2 O grape wine skin extracts in a way of scavenging DPPH radicals, showing that biowaste obtained from grape wineskins could be used as an immense source of bioactive compounds with high antiradical activity. Material and Methods: Electron Paramagnetic Resonance (EPR) spectroscopy was used to detect the activity of grape skin extracts toward DPPH radicals and UHPLC-DAD MS/MS analysis to separate, identify and quantify their active components. Results: The results show that Cabernet Sauvignon and Pinot Blanc grape skin extracts have unexpectedly large potential to remove DPPH radicals from the system. Having in mind the concentration of redox-active components obtained by UHPLC-DAD MS/MS analysis and presented EPR results, there is strong evidence that primarily quercetin 3-O-glucoside, as well as kaempferol 3-O-glucoside, isorhamnetin 3-O-glucoside, kaempferol 7-O-glucoside supplemented with catechin and rutin are responsible for the antioxidative capacity of extracts. Conclusions: This study demonstrates that extracts obtained from grape skins, initially intended as biowaste, exhibit high antiradical activity. The largest quantity of the most redox-active components could be found in 50% EtOH extracts, which we propose to be the starting material for making potent redox-active cosmetic products and dietary supplements. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central European Agriculture is the property of Journal of Central European Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Agriculture / Poljoprivreda is the property of Josip Juraj Strossmayer University of Osijek, Faculty of Agriculture in Osijek and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Agriculture / Poljoprivreda is the property of Josip Juraj Strossmayer University of Osijek, Faculty of Agriculture in Osijek and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cereals are considered one of the most commonly used foods due to their properties. They are the main source of carbohydrates, mainly starch. In addition to carbohydrates, cereals also contain proteins, unsaturated fatty acids, minerals, B-group vitamins and vitamin E. This composition refers to the unprocessed form of cereals - whole grain cereals. They also contain phenolic compounds, such as phenolic acid, flavonoids, stilbene, coumarins and tannins. These are plants secondary metabolites and have a significant role in the prevention of many diseases due to their antioxidant properties. The aim of this research was to determine the content of total polyphenols and tannins in wheat (type 500), maize, rye and whole wheat flour extracts, as well as the antioxidant activity of the samples. The highest content of total polyphenols was determined in whole wheat flour (6.38 ± 0.759 mg GAE/g), while the lowest amount was determined in wheat (type 500) flour (2.29 ± 0.32 mg GAE/g). Whole wheat flour extract showed the highest antioxidant activity (IC50 = 5.63 ± 1.331 mg/ml), while wheat flour (type 500) extract showed the lowest antioxidant activity (IC50 = 26.39 ± 2.132 mg/ml). Based on the results obtained, it can be concluded that whole grain cereals contain a large amount of polyphenols, which indicates a significant antioxidant activity. Due to their many properties, which have effect on improving health, cereals form the base of the pyramid of nutrition, as a model of healthy eating. [ABSTRACT FROM AUTHOR]

Literature reports have shown that supercritical extraction is a promising method to obtain bioactive compounds used to develop drugs based on natural products. This work investigated the yield, antioxidant activity, and phytochemical constituents of the extracts obtained from Vernonia amygdalina Delile leaves with supercritical CO2. The supercritical extraction was examined at temperatures of 40, 50 and 60 °C and at pressures of 200 and 250 bar. The supercritical fluid extraction (SFE) method was compared with the classical Soxhlet using different solvents at atmospheric pressure. The overall yield obtained using SFE varied from 0.69 to 1.24%. The extraction conditions which favored the highest yield were 60 °C and 250 bar. The overall SFE curves were fitted using three mathematical models. All of them were able to describe satisfactorily the extraction kinetics. Spline model presented the best fit to experimental data and was able to characterize constant and decreasing extraction rate periods. Extracts were characterized by gas chromatography coupled with mass spectrometry technique and some major components were identified. The antioxidant activity tests showed that the SFE extracts had low antioxidant activity exhibiting the estimated concentration of extract required to reduce 50% of the stable free radical DPPH (EC50) values to be between 622.62 and 937.88 μg mL-1. [ABSTRACT FROM AUTHOR]

Cat's whiskers (Orthosiphon stamineus) is a medicinal plant which comprises several dynamic pharmacological properties such as anti-inflammatory, antioxidant and antibacterial. In small and medium-scale industries, conventional reflux extraction method is favored as compared to other non-conventional extraction methods due to cost effectiveness and simple operating procedures. In this study, response surface methodology (RSM) was applied to optimize the reflux conditions for extraction of cat's whiskers leaves in order to achieve a high content of antioxidant activity in the extracts. Central composite experimental design (CCD) with three factors and three levels was employed to consider the effects of the operation conditions. Antioxidant activity of the extracts were based on free radical scavenging activity (DPPH assay) and were analyzed using a UV-Vis spectrophotometer. Based on RSM, the antioxidant activity could be maximized when the operation conditions were 125 µm for particle size, 1.5:20 for sample-to-solvent ratio, and 2 h for extraction time. Under these optimal conditions, the predicted value of the antioxidant activity was compared with the actual, and the mean error was 0.46%. This indicates the suitability of the model for optimizing the conditions for the reflux extraction of cat's whiskers leaves. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central European Agriculture is the property of Journal of Central European Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim: To determine the difference in the antioxidant activity of the olive, sunflower, pumpkin and black oil and their tocopherol extracts as well as to examine the kinetics and mechanism of reactions between free radicals and antioxidants. Materials and Methods: Antioxidant activity of the oils and tocopherol extracts was measured spectrophotometrically using DPPH. (2,2-diphenyl-1-picrylhydrazil) while Trolox equivalent was used as a reference standard for the quantification of the results obtained by the DPPH. test. DPPH. signal inhibition was evaluated and analyzed by monophasic and biphasic kinetics mathematical models. Results: The TEAC values suggest that olive and sunflower oil (2.16 mmol/L) have a stronger antioxidant activity than black (1.85 mmol/L) and pumpkin oil (1.68 mmol/L) and they possess stronger inhibition of the DPPH. radical. Tocopherol extracts have a much weaker antioxidant effect than the analyzed vegetable oils, where the sunflower extract is most effective, making 22.1 % of the antioxidant oil activity, while the weakest extract is the pumpkin oil extract oil with only 13.9 %. DPPH. radical disappearance in oil samples takes place in two successive phases, the initial exponential which takes place within 7 min of the reaction, depending on the oil type, and the second slow phase where the changes are proportional to the time. The rapid reaction phase by tocopherol extracts was not noticed, indicating that the reaction takes places by the mechanism of the first order kinetics. Conclusion: The results indicate that vegetable oils have a stronger effect on the radical inhibition than the tocopherol extracts, and by their proper consumption they will support the organism in the "fight" against free radicals. In addition, the most important role of the antioxidant defense system against free radicals makes the synergic interactions among the different molecules present in the food, indicating that antioxidants in synergy have a stronger potential than the sum of all individual antioxidants. [ABSTRACT FROM AUTHOR]

Chokeberry (Aronia melanocarpa (Michx.) Elliott) has been traditionally used for centuries in the herbal medicine of the Native North Americans considering the numerous pharmacological activities. The aim of this research was to analyze the effects of the chokeberry juice on the cardiovascular activity, in order to authenticate the use of Aronia melanocarpa as a functional food. Nevertheless, the antioxidative properties of chokeberry juice were determined by DPPH method and the ß-carotene/linoleic acid model system, to prove the estimated activity of the juice. The significant antioxidative activity was confirmed. The concentration of chokeberry that inhibited 50% of DPPH free radicals (IC50) was 1.25 ± 0.08 mg/ml. In ß-carotene/linoleic acid model system IC50 was achieved by concentration of 1.73 ± 0.07 mg/ml. The effects of chokeberry juice on the blood pressure and heart rate in anaesthetized rabbits were performed. The results demonstrated the reduction of the blood pressure (EC50 value of 195.63 ± 14.45 mg/kg, the concentration which elicited 50% of maximal response) and heart rate (EC50 value of 171.71 ± 11.21 mg/kg) in the animals. The administration of the chokeberry juice could produce hypotension and negative chronotropic effects. However, it is necessary to conduct the study in human population to confirm those findings. [ABSTRACT FROM AUTHOR]