Antiradical Activity Of Extracts Research Articles

Evaluation of gamma irradiation effects on antioxidant capacity of propolis

The irradiation effects on antioxidant potential and on content of phenolic compounds of propolis ethanoic extracts were studied. It was found out that gamma treatment of samples with 2 and 10 kGy had a weak decreasing effect on the total phenolic content (TPC), while no change was observed in the propolis irradiated with 5 kGy. The antiradical activity of extracts was assessed by the DPPH free radical scavenging activity evaluated by Electron Paramagnetic Resonance (EPR) spectroscopy. The EPR results were in agreement with TPC. Some main phenolic compounds of the studied non-irradiated and irradiated samples were identified and compared by ultra-high performance liquid chromatography (UHPLC).

Composition of Biologically Active Substances and Antiradical Activity of Extracts from Five Species of Plants of the Asparagaceae Family

Composition of Biologically Active Substances and Antiradical Activity of Extracts from Five Species of Plants of the Asparagaceae Family

Effects of Gamma Irradiation on Free Radical Components, Phenolic Content and Antioxidant Activity of Beebread

Antiradical activity and free radicals before and after gamma-treatment of beebread were investigated by Electron Paramagnetic Resonance (EPR) spectroscopy. A narrow signal the intensity of which increased with the dose was assigned to O-centred free radicals induced by gamma rays. They are stable for 120 days after irradiation. The irradiation effect on antioxidant potential and content of phenolic compounds were studied. It was found that total phenolic and flavonoid content values increased after beebread irradiation depending on the dose. The antiradical activity of extracts was assessed by the DPPH free radical scavenging activity. The EPR study showed that it increased after irradiation with 5 kGy (27%) and 20 kGy (19%), while the slight decreasing (6%) was observed after irradiation at 10 kGy.

Melissa officinalis L. nanoethosomal formulation: evaluation of antioxidant, enzyme inhibitory activities and in vitro toxicity

ABSTRACT This work aimed to create an extract of Melissa officinalis L. with strong antiradical efficacy, characterize it, and enhance its long-term efficacy by developing an ethosomal formulation. DPPH and ABTS assays were used to test the antiradical activity of extracts with different ethanol ratios obtained from the aerial part. Phytochemical characterization of the extract with the highest activity, ethyl acetate fraction of 60% ethanol extract, was analyzed by HPLC. The active ethyl acetate fraction was loaded into ethosomes, and characterization and release studies of the formulation were performed. The released extract from the formulation exhibited substantial antiradical action as well as inhibition of collagenase (71.5%) and elastase (75.5%) enzymes. The toxicity of the active extract and the formulation was determined in the mouse fibroblast cell line. This study successfully developed a long-term antioxidant and enzyme inhibitor formulation containing M. officinalis, which stands out for its medicinal properties.

In vitro inhibition of starch digestive enzymes by ultrasound-assisted extracted polyphenols from Ascophyllum nodosum seaweeds.

Seaweeds are gaining importance due to their antidiabetic characteristics. This study investigated the inhibitory effects of aqueous Ascophyllum nodosum extracts, obtained by ultrasound‐assisted extraction with different sonication powers (70–90 W/cm2) and subjected to resin purification, against α‐amylase and α‐glucosidase enzymes. Different inhibition methodologies were carried out, preincubating the extract either with the enzyme or the substrate. Chemical characterization, in terms of proximate analysis, antioxidant capacity (2,2‐diphenyl‐1‐picryl‐hydrazyl‐hydrate [DPPH] and FRAP), and polyphenols characteristics (reversed‐phase high‐performance liquid chromatography [RP‐HPLC] and 1H‐NMR) were carried out to explain inhibitory activities of extracts. Sonication power did not influence the proximal composition nor antiradical activity of extracts, but increasing sonication power increased inhibition capacity (>15%) against both starch digestive enzymes. The extract purification largely improved the inhibition efficiency decreasing the IC50 of α‐amylase and α‐glucosidase by 3.0 and 6.1 times, respectively. Seaweed extracts showed greater inhibition effect when they were preincubated with the enzyme instead of the substrate. RP‐HPLC together with 1H‐NMR spectra allowed relating the presence of uronic acids–polyphenols complexes and quinones in the extracts with the different inhibitory capacities of samples.Practical ApplicationThe study confirms that ultrasound‐assisted extracts from Ascophyllum nodosum can be used to inhibit digestive enzymes. This opens the alternative to be used in foods for modulating glycemic index.

Изучение антиоксидантной активности травы чины клубненосной (Lathyrus tuberosus L.)

Objective: to study the antioxidant and antiradical activity of extracts from the tuberous pea herb. Materials and methods. The study object was tuberous pea herb collected in Kursk region in 2020-2021 during the flowering period of plants. The antioxidant and antiradical activities of aqueous and aqueous-alcoholic extracts from the herb of tuberous pea were investigated. Antioxidant activity was evaluated by titrimetric method based on the interaction of potassium permanganate and reducing substances contained in the extract from raw materials of tuberous pea herb. The antiradical activity was studied by spectrophotometric method according to the ability of extracts to inactivate 1,1-diphenyl-2-picrylhydrazyl. The content of phenolic compounds (direct spectrophotometry) in terms of chlorogenic acid and flavonoids (differential spectrophotometry) in terms of rutin was determined. The obtained data were processed by statistical analysis. Results. By the example of the use of different extractants: water and alcohol of different concentrations, we investigated their influence on the antioxidant and antiradical activity of tuberous pea herb. The analysis of the experimental data obtained showed that all the extracts studied have antioxidant and antiradical activity, with the maximum activity found in extracts obtained from the herb using 50% and 70% ethyl alcohol as an extractant. The maximum content of phenolic compounds and flavonoids was also found in the mentioned extracts, which indicates a correlation between the antioxidant activity and the content of phenolic compounds. Conclusion. The results of the conducted experimental study allow us to conclude that the tuberous pea herb harvested in the flowering phase can be considered as a promising medicinal plant raw material of antioxidant orientation.

ANTIRADICAL ACTIVITY OF EXTRACTS FROM SIBERIAN FLORA GENUS CENTAUREA PLANTS

The purpose of this research is to study the antiradical activity of various extracts from the Centaurea scabiosa L. aerial part (wild-growing and cultivated) and Centaurea jacea L. as potential sources of antioxidant herbal remedies.
 In the study of the antiradical activity of extracts from the aerial part of Centaurea jacea L., Centaurea scabiosa L. wild growing and cultivated, in the reaction with a stable diphenylpicrylhydrazyl radical, it was found that the degree of antiradical activity within each species correlates with the quantitative content of flavonoids. Lower values ​​of the antiradical activity of cultivated Centaurea scabiosa L. extracts compared to wild growing Centaurea scabiosa L. extracts are consistent with a lower content of flavonoids in the latter.
 The dependence of the Centaurea jacea L. and wild growing Centaurea scabiosa L. extracts antiradical activity on flavonoids quantitative and qualitative composition of these species has been established.

Antiradical and Lipid Peroxidation Inhibitory Activity of Ripe and Unripe Fruit of Rubus steudneri Schweinf. (Rosaceae)

Objectives: A free radical is a molecular species characterized by the presence of an unpaired electron in its outer orbital. Free radicals are highly reactive and are known to damage biomolecules including lipids resulting in a myriad of pathophysiological conditions. The present investigation was carried out to screen antiradical and lipid peroxidation inhibitory activity of ripe and unripe fruit of R. steudneri. Methods: The powdered ripe and unripe fruit materials were extracted by maceration process using methanol. Antiradical activity of extracts was evaluated by DPPH and hydroxyl radical scavenging assays. Lipid peroxidation inhibition assay was carried out by estimating the thiobarbituric acid reactive substances. Both ripe and unripe fruit extracts were screened for the presence of phytochemicals viz. alkaloids, flavonoids, tannins, phenolic compounds, saponins, glycosides, sterols and triterpenoids by standard tests. Results: Preliminary phytochemical analysis indicated that both ripe and unripe fruit extracts contain saponins, alkaloids, phenolic compounds, flavonoids, tannins, sterols and triterpenoids. When compared to unripe fruit extract, ripe fruit extract displayed marked scavenging of DPPH and hydroxyl radicals and inhibition of lipid peroxidation as indicated by lower IC50 values. Conclusion: Overall, ripe fruit extract displayed marked free radical scavenging and lipid peroxidation inhibitory activity. The presence of phenolic and flavonoid compounds in the extracts might be responsible for observed bioactivities of ripe and unripe fruit of R. steudneri.

Total Phenolic Content, Antiradical and Antimicrobial Activity of <i>Hoya wightii</i> and <i>Hoya ovalifolia</i>

Antiradical and antimicrobial activity of leaf extract of Hoya wightii Hook.f. and Hoya ovalifolia Wight & Arn. was screened in this study. Antibacterial and antifungal activity of leaf extracts was determined by Agar well diffusion and Poisoned food technique respectively. Antiradical activity was evaluated by DPPH and ABTS radical scavenging assays. The content of total phenolics was estimated by Folin Ciocalteau reagent method. Extract of H. ovalifolia displayed marked antiradical and antimicrobial activity when compared to extract of H. wightii. Phenolic content was found to be higher in H. ovalifolia . A positive correlation was observed between the phenolic content and antiradical activity of extracts.

Analysis of Polyphenolic Compounds in Extracts from Leaves of Some Malus domestica Cultivars: Antiradical and Antimicrobial Analysis of These Extracts.

In this study, methanol, ethyl acetate, water extracts, and precipitate were obtained from leaves of Malus domestica cultivars: Golden delicious, Jonagold, Elstar, Ligol, and Mutsu. Antiradical activity of these extracts was measured using the ABTS+∙ radical, and antimicrobial activity was measured with the disk-diffusion method. Phenolic compounds were measured with the colorimetric method and identified with high performance liquid chromatography (HPLC). The highest antiradical activity was observed for the Jonagold variety, and in particular strong activity was noted for ethyl acetate extracts. Antimicrobial activity was observed against strains of Staphylococcus aureus, Enterococcus faecalis, and the fungus Candida glabrata. Particularly susceptible to the extracts activity appeared to be Staphylococcus aureus, but the growth of Candida glabrata was inhibited in the presence of ethyl acetate extracts. With the HPLC method we identified a high amount of phloridzin (above 500 mg per g of ethyl acetate extracts), lower amounts of hyperoside, isoquercitrin, and quercitrin, and traces of p-hydroxybenzoic and chlorogenic acids. The contribution of phloridzin to antiradical activity of methanol and ethyl acetate extracts was very high (above 90%). In water extract the contribution of phloridzin was between 38.9 and 55.2%, chlorogenic acid 22.7 and 36.1%, and hyperoside 12.2 and 13.3%.

Evaluation of antiradical assays used in determining the antioxidant capacity of pure compounds and plant extracts

The efficiency of the chemiluminescence luminol method and colorimetric DPPH and ABTS methods in evaluating the antiradical capacity of pure compounds and plant extracts with antioxidant potential is compared. In case of pure compounds, the values of parameter 'n' (number of radicals quenched per molecule of antiradical) for ascorbic acid, p-hydroquinone, catechol, quercetin, and rutin are similar when measured by colorimetric assays; however, considerably lower values of n are obtained with the luminol assay. The antiradical activity of extracts from male and female individuals of Baccharis burchelli and Baccharis crispa were determined by the luminol assay and expressed using the new Trolox® percentage (%Trolox®) parameter.

Effect of extraction method on phenolic content and antioxidant activity of mistletoe extracts from Viscum album subsp. abietis

AbstractThe total content of polyphenols and flavonoids determined in the same plant and their corresponding antioxidant activities may vary widely, depending on the extraction conditions applied. This study was conducted to optimise the extraction conditions of phenolics and flavonoids from the mistletoe plant. Various extraction methods, i.e. ultrasound-assisted extraction technology, maceration, maceration with stirring, accelerated solvent extraction (ASE), and extraction under reflux were evaluated for their percentage extraction of polyphenols (TPC) and flavonoids (TFC) from Viscum album subsp. abietis. In addition, the anti-radical activity of extracts was analysed using the 2,2-diphenyl-1-picrylhydrazyl method. The effects of temperature, solvent type, and concentration on the phenolic extraction efficiency and antioxidant activity were studied using chemometric and statistical methods. The results showed that the extracts of V. album subsp. abietis contained large amounts of polyphenols and flavonoids (up to 57.673 mg g−1 and 9.955 mg g−1 of dry extract, respectively) and exhibited potent antioxidant activity, hence representing promising sources of powerful antioxidants. Due to its high extraction efficiency and considerable saving of time and solvent, ASE was more effective than the other extraction techniques. Extracts prepared with water-polar solvent mixtures displayed the highest TPC, TFC, and antioxidant activity, while organic polar solvents were the least efficient extractants.

Investigation of antiradical potential of different kinds of teas and extracts from these teas using antiradical activity units (TAU)

Green, black and pu-erh teas are known to have strong antiradical properties in comparison to other plant raw materials. In this study fifteen different teas belonging to three types, green, black, and pu-erh tea (five of each kind), were investigated for their antiradical properties. Antiradical activity of extracts and raw materials was measured using DPPH and ABTS(•+) radicals. The antiradical potential of teas was measured using DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS(•+) (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt). The TAU₅₁₅ and TAU₇₃₄ (antiradical activity units) were defined with the tests of DPPH and ABTS(•+), respectively, and the number of units was calculated per mg of extracts (TAU(515/mg) and TAU(734/mg)) and g of raw materials (TAU(515/g) and TAU(734/g)). When the extracts were investigated, the highest number of antiradical units (TAU(515/mg); TAU(734/mg)) was found per mg of ethyl acetate extract obtained from green tea leaves assayed with DPPH and ABTS(•+): 57.7±0.8; 106±2.0, units respectively. When the number of antiradical units TAU(515/g) was calculated per g of raw material, the highest antiradical potential (7601±92) was observed for green tea leaves. The greatest TAU(734/g) value (14,303±354) was also calculated for green tea leaves. The lowest value of antiradical activity units TAU(515/g) (684±30) and TAU(734/g) (1870±180) was calculated for pu-erh tea leaves. A high positive correlation was found between the antiradical activity of the raw materials and the content of phenolic compounds in these raw materials.

Accelerated Solvent Extraction: development of a representative extraction method from medicinal plants for cosmetic applications

The first crucial step to discover new cosmetic plant active ingredients is the extraction before the analysis of plant materials. Accelerated Solvent Extraction (ASE) is a fast and automatic sample preparation technique which offers the ability to carry out sequentially multiple extracts (up to 24 samples).Then, cosmetic activities (enzymatic targets and skin cells) can be evaluated. For preliminary phytochemical investigations, an efficient and exhaustive method is traditionally used to extract polar plant metabolites. The aim of our study was to define ASE conditions to obtain the most complete and representative extraction. In contrary, most of publications deal with the optimization of operational parameters to enhance the selectivity of extraction of only compounds of interest. The transposition of our conventional solvent-based extraction method (hydroethanolic reflux extraction, 1h, ratio plant/solvent 10%) to ASE technology was performed with respect of amount of extracted material (dry matter, yield) and chemical composition. Among herbs selected, ASE extracts of Lespedeza capitata Michx. and Scutellaria baicalensis Georgi extracts were obtained and analyzed by Thin-Layer Chromatography. The flavonoids content of the extract was identified by HPTLC coupled with UV densitometric detection. The quantification of orientin/homorientin and baicalin/baicalein was achieved to select the best ASE parameters (50°C, 10min, ratio plant/solvent 20%). In addition, the antiradical activity of extracts was evaluated. The results showed that optimized ASE extracts were equivalent to conventional ones concerning phytochemical composition and antiradical activity. To conclude, such standardization of ASE extraction method is a powerful tool for rapid screening of new cosmetic plant active ingredients.

Antiradical activity of seven Plantago species from Serbia and Montenegro

Plantago species are widely distributed in Europe and 14 species are described in the Flora of Serbia [1]. In Asia and Europe, Plantago species have been used in folk medicine for the treatment of certain respiratory and digestive diseases, and wound healing [2]. Phytochemical investigation of the genus revealed the presence of iridoid glycosides and various phenolics [3]. In our study, 50% ethanolic extracts of Plantago lanceolata, P. atrata, P. bellardii, P. coronopus, P. holosteum, P. reniformis, and P. schwarzenbergiana leaves were investigated regarding the contents of total phenolics, phenylpropanoid glycosides (PPG), and iridoids. Antiradical activity of extracts was characterized by the DPPH scavenging test. The amount of total phenolics varied from 9.28–24.98mg GAE/g DW, and decreasing order was P. lanceolata > P. schwarzenbergiana > P. holosteum > P. atrata > P. reniformis > P. bellardii > P. coronopus. Regarding the PPG content, the highest amount was present in P. lanceolata (8.88%), and P. atrata contained the lowest amounts of PPG (1.55%). The most abundant in iridoids were P. holosteum, P. atrata and P. lanceolata (14.54, 12.52 and 12.25mg/g, respectively). The highest scavenging activity toward DPPH radical was observed in P. lanceolata (IC50=0.25mg/ml), while the lowest activity was shown by P. coronopus (IC50=0.77mg/ml). The scavenging effect of extracts decreased in the same order as with total phenolic content, and the relationship between total phenolic content and antiradical activity of extracts was observed with statistically significant correlation (r=–0.95).

Kinetic method for studying the antiradical activity of medicinal plant extracts

A kinetic method for studying the activity of medicinal plant extracts with respect to the stable 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical is developed. The initial rate of DPPH decay under standard conditions is suggested and theoretically justified as a kinetic parameter to compare the antiradical activity of extracts. A 10- to 150-fold decrease of the DPPH reaction rate with antioxidants (AO) of plant extracts in aqueous EtOH is achieved by adding acids to the reaction medium. The reaction at the optimum acid concentration decreases with increasing acid strength. Using this approach, the influence of organic acids extracted from the plant material on the results can be eliminated by adding stronger acids. The noise level on the kinetic curves and, therefore, in the measurement error, is decreased by smoothing the data using a general equation of the kinetic curve obtained using the Microcal Origin 7.0 and SYSTAT TableCurve 2D 5.01 software. It is found that the extent of DPPH conversion in the interval from 0 to 60% after the first 30 min depends linearly on the initial AO concentration.

The antiradical activity of extracts from some wild-growing plants of the Okhotsk Sea northern coastal region

The antiradical activity of aqueous ethanol extracts from some edible plants and berries of the Okhotsk Sea northern coastal region was assessed using the method of bleaching (quenching) of stable free radicals of N,N-diphenyl-N′-picrylhydrazyl. Some of the obtained extract showed significantly higher activity as compared to that of the available commercial preparation from dried bilberry fruit. The high activity was retained even after high-temperature drying of the initial material, which makes it possible to use such a drying stage in the technology of products subject to long-term storage.

Effect of Solvent, Temperature, and Solvent-to-Solid Ratio on the Total Phenolic Content and Antiradical Activity of Extracts from Different Components of Grape Pomace

Grape byproducts were subjected to an extraction process under various different experimental conditions (namely, solvent type, temperature, solvent-to-solid ratio, time contact, and raw material) in order to study the effect of these conditions on the yield of phenolic compounds and the corresponding antiradical activity of extracts. Although the order of decreasing capacity to extract soluble materials was ethanol > methanol > water, methanol was the most selective for extracting phenolic compounds. Temperature and solvent-to-solid ratio were found to have a critical role in extraction efficiency; values of 50 degrees C (between 25 and 50 degrees C) and 1:1 (between 1:1 and 5:1) maximized the antiradical activity of phenolic extracts. In addition, extracts from grape samples previously subjected to distillation reached higher antiradical values in comparison to those coming directly from pressing; in both cases, seed extracts showed better results than those of stem when ethanol or water was employed, whereas the opposite occurred in the case of methanol. These differences were attributed to the different phenolic compositions of the considered fractions.