Antioxidant and antimutagenic activity of phenolic compounds in three different colour groups of common bean cultivars (Phaseolus vulgaris)

Total phenolic content of seven improved common bean cultivars (Phaseolus vulgaris L.) namely, Negro Altiplano, Negro Durango, Negro Sahuatoba, Flor de mayo sol, Flor de Mayo Bajío, Flor de Mayo 94044MX and Bayo Madero were analyzed. Acetone and methanol extracts from bean cotyledons were obtained by successive extractions. Total phenolic content was evaluated following Folin–Ciocalteu method; antioxidant activity by the DPPH technique; antimutagenic potential by the Ames method; and preliminary identification was realized by 2D-TLC. Results indicated high correlation between total phenol content and antioxidant activity for acetone extracts, and also high correlation between antioxidant and antimutagenic activities. In contrast, low correlation coefficients were obtained for methanol extracts. Three cultivars (two Negro cultivars and a Flor de Mayo type) showed lower antimutagenic activity than catechin.     

Evaluation of Antioxidant and Antimutagenic Activities of the Extracts from the Fruit Rinds of Garcinia cowa

Recent studies have reported the biological activities of the crude extracts/purified compounds from various parts of Garcinia cowa. In the present study, the dried fruit rinds of G. cowa were extracted with hexane and chloroform and the extracts were used to evaluate their antioxidant and antimutagenic activities. Using β-carotene-linoleate-model system, at 200 ppm concentration, hexane, chloroform extracts and butylated hydroxyanisole (BHA) showed 91.7, 93.7, and 98.0% antioxidant activity, respectively, whereas, at 50 ppm concentration the radical scavenging activity was 83.3, 86.3, and 88.5%, respectively, through DPPH method. At a concentration of 5000 μg/plate, hexane extract exhibited strong antimutagenicity against the mutagenicity of sodium azide in both the tester strains of Salmonella typhimurium (TA-100 and TA-1535). Chloroform extract showed strong antimutagenicity in both the tester strains at a concentration of 2500 μg/plate and above. However, the chloroform extract exhibited higher antioxidant and antimutagenic activities than that of hexane extract. This study showed that both the extracts from the fruit rinds of G. cowa possess antioxidant and antimutagenic properties.     

Antioxidant and antifungal activities of extracts from 15 selected hardwood species of Malaysian timber

The antioxidant activities, total phenols and antifungal activities of 35 extracts samples from 15 species of Malaysian timber were investigated. The methanol extracts from Mangifera indica heartwood were found to have superior antioxidant activity with an EC₅₀ value of 4.71±0.89 μg/ml. Antioxidant activities correlated with total phenols contents. The methanol extracts from Neobalanocarpus heimii bark and Cinnamomum porrectum heartwood showed moderate antifungal activity against a brown-rot fungus, Gloeophyllum trabeum. The methanol extracts from Neobalanocarpus heimii bark and Endospermum malaccense inner wood showed the highest antifungal activity against a white-rot fungus, Pycnoporus sanguineus, at a minimum effective amount of 100 μg. The activities of these extracts were equal to the activity of the positive control, glycyrrhizic acid dipotassium salt, suggesting that they have great potential as a source of fungistats.     

Evaluation of the antioxidant potential of Pittosporum dasycaulon Miq. stem bark

The in vitro antioxidant properties of methanol and aqueous extracts of stem bark from Pittosporum dasycaulon Miq. were investigated. Fractions were screened for total antioxidant capacity, ferric reducing power, and radical scavenging activities. The total phenolic, flavonoid, and tannin contents of the methanol and aqueous extracts were also determined. The aqueous extract exhibited a stronger scavenging effect than the methanol extract against the DPPH free radical, the nitric oxide radical, and the superoxide radical. The methanol extract exhibited a stronger total antioxidant activity and reducing power than the aqueous extract. The free radical scavenging effect of P. dasycaulon stem bark extracts was comparable to an ascorbic acid reference antioxidant while the reducing power of the methanol extract was greater than ascorbic acid. P. dasycaulon stem bark is a potential source of natural antioxidant compounds.     

Comparative study on the antioxidant activity of methanolic and aqueous extracts from the fruiting bodies of an edible mushroom <Emphasis Type="Italic">Pleurotus djamor</Emphasis>

In vitro antioxidant activities, total phenolic, and flavonoid contents of Pleurotus djamor extracts were analyzed based on radical scavenging activities of methanol and aqueous extracts using 1,1-diphenyl-2-picryl-hydrazyl (DPPH), N,N-dimethyl-p-phenylenediamine (DMPD), total Fe³⁺ reducing power, CUPRAC, phosphomolybdenum, metal chelating activity, and lipid peroxidation inhibition assays. Both extract types showed efficient radical scavenging activities against DPPH and DMPD radicals, ferric (Fe³⁺) and cupric (Cu²⁺) ion reducing powers, metal chelating activities, and lipid peroxidation inhibition. Total phenolic contents of methanol and aqueous extracts were 2.79 and 5.95 mg of GAE/g, respectively. Flavonoid contents of methanol and aqueous extracts were 6.35 and 5.75 mg of CAE/g, respectively. Consumption of the mushroom P. djamor can be beneficial due to antioxidant properties.     

Antioxidative, antiradikale und antimikrobielle Aktivitäten des Fruchthüllen-Extrakts von frischen Antep-Pistazien

Pistacia vera L. is the only genus of more than ten in Pistacia species consumed as a nut and has commercial value. Turkey is one of the homelands of the pistachio species, and they are named Antep pistachio. When Antep pistachios are processed into nuts, their reddish purple hulls are removed as a waste after the processing. In this research, Antep pistachio hull samples extracted by methanol, ethanol and water were tested for antioxidant and antiradical (IC₅₀ value) potentials, and antimicrobial activities as well. The values of total phenolic content of methanol extracts of Antep pistachio hull was 167.49 ± 0.48 mg gallic acid equivalent (GAE)/g dry extract. The ethanol and aqueous extract of the pistachio hulls were determined as 89.87 ± 0.44 and 31.73 ± 0.21 mg GAE/g dry extract, respectively. The antioxidant activities of extracts were evaluated by the phosphomolybdenum method. The highest antioxidant activity of the hull extracts was determined in the methanol extracted samples (152.10 ± 0.19 mg ascorbic acid equivalent (AAE)/g dry extract), while the lowest value was in the ethanol extracts (15.19 ± 0.00 mg AAE/g dry extract). The values of IC₅₀ in methanol, ethanol and aqueous extracts of the pistachio hulls were 16.01, 21.62 and 24.45 μg/ml, respectively. The highest antiradical activity was in the methanol extract of Antep pistachio hulls. In this research, the pistachio hull extracts were tested for antimicrobial activities against total 15 microorganisms, 13 bacteria and 2 yeasts. The aqueous extract of the hull was the most ineffective extract against the microorganisms tested. The methanol and ethanol extracts of the pistachio hulls, which had limited antimicrobial effect against the bacteria, Mycobacterium smegmatis, Salmonella typhimurium, Proteus mirabilis and Yersinia enterocolitica, and the yeasts, Saccharomyces cerevisiae and Candida albicans, and were effective on the other microorganisms constituted inhibition zones diameter as between 10 and 39 mm. All extracts of the pistachio hulls exhibited antimicrobial activity against Listeria monocytogenes (6–38 mm) and Escherichia coli O157: H7 (8–28 mm). In conclusion, the hulls of Antep pistachio can be evaluated as a potential antimicrobial and antioxidant resource in the food systems.     

Phenolic profile,antioxidant, anticholinesterase,and anti-tyrosinase activities of the various extracts of Ferula elaeochytris and Sideritis stricta

In this study, the antioxidant, anticholinesterase, and anti-tyrosinase properties of (hexane, acetone, methanol, and water) extracts of Ferula elaeochytris and Sideritis stricta were determined with the total phenolic and flavonoid contents. The phenolic profile of the methanol and water extracts was analysed using HPLC-DAD. Protocatechuic acid was found as the major phenolic compound in the methanol (116.3 ± 3.1 µg/g) and water extracts (69.4 ± 1.3 µg/g) of F. elaeochytris. Coumarins (253.9 ± 4.1 µg/g) and catechin hydrate (175.2 ± 2.9 µg/g) were the most abundant phenolic compounds in the methanol and water extracts of S. stricta. β-carotene–linoleic acid, DPPH^?, ABTS^?+, CUPRAC, and metal-chelating assays were used to evaluate antioxidant properties of the extracts. The methanol and water extracts of F. elaeochytris and the acetone and methanol extracts of S. stricta containing the highest amount of total phenolic and flavonoid contents showed the highest antioxidant activities in β-carotene–linoleic acid, DPPH^?, ABTS^?+, and CUPRAC assays. The enzyme inhibitory potential of extracts was investigated against key enzymes involved in neurodegenerative (acetylcholinesterase (AChE) and butyrylcholinesterase (BChE)) and skin (tyrosinase) disorders. In the cholinesterase inhibitory assays, the hexane extracts of two species exhibited the best activity against AChE, while the hexane extract of F. elaeochytris and the methanol extract of S. stricta observed to be the most active against BChE. As for anti-tyrosinase activity results of extracts, the only acetone and methanol extracts showed mild inhibitory activity for both species.     

Antioxidant activity of the essential oil and various extracts of Nepeta flavida Hub.-Mor. from Turkey

This study was designed to examine the chemical composition and in vitro antioxidant activity of the essential oil and various extracts (hexane, dichloromethane and methanol sub-fractions) of Nepeta flavida. GC and GC–MS analyses of the essential oil resulted in the identification of 68 compounds, representing 96.4% of the oil; 1,8-cineole (38.9%) and linalool (25.1%) were the main components, comprising 64.0% of the total oil. The samples were subjected to a screening for their possible antioxidant activities by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and β-carotene-linoleic acid assays. In the first case, the IC₅₀ value of the N. flavida essential oil was determined to be 42.8 ± 2.19 μg/ml. Among the extracts, the strongest activity was exhibited by the polar sub-fraction of the methanol extract with an IC₅₀ value of 63.2 ± 1.75 μg/ml. In the β-carotene-linoleic acid system, N. flavida essential oil exhibited 86.3% ± 1.69 inhibition against linoleic acid oxidation. Among the extracts prepared with various solvents, a correlation was observed between the polarity and antioxidant activity. The extracts exhibited the same activity pattern in this system the most active one is the polar sub-fraction, 79.7% ± 0.89. On the other hand, 1,8-cineole, a major compound of the essential oil, exhibited marked antioxidant activity in both systems, whereas the other compound, linalool, did not show any activity. The amount of total phenolics was highest in the polar and non-polar sub-fractions. Particularly, a positive correlation was observed between the total phenolic content and the antioxidant activity of the extracts. As estimated from the results, amounts of phenolic compounds were less in hexane and dichloromethane extracts than in the others. In conclusion, antioxidant potentials of polar and non-polar methanol sub-fractions could be attributed to their high phenolic contents. In both systems, antioxidant capacities of BHT, ascorbic acid, curcumin and α-tocopherol were also determined in parallel experiments.     

Phytochemicals and antioxidant activity of different parts of bambangan (Mangifera pajang) and tarap (Artocarpus odoratissimus)

Mangifera pajang (family: Anacardiaceae; local name: bambangan) and Artocarpus odoratissimus (familiy: Moraceae; local name: tarap) are popular edible fruits in Sabah, Malaysia. The flesh, kernel and peel from M. pajang; seed and flesh from A. odoratissimus were analysed for total antioxidant activity, total polyphenol, total flavonoid and total anthocyanins contents. M. pajang kernel extract displayed the highest free radical scavenging and ferric reducing activities. Total phenolic content of the samples were in the range of 5.96–103.3 mg gallic acid equivalent/g. M. pajang kernel and M. pajang flesh contained the highest and lowest total flavonoid content with the values of 10.98 and 0.07 mg rutin equivalent/g, respectively. The antioxidant activities of extracts were significantly correlated with the total phenolic and flavonoid content (but not the anthocyanins content). The phytochemicals and antioxidant properties of M. pajang and A. odoratissimus, especially their by-products (kernel/seed), indicate that they may impart health benefits when consumed and should be regarded as a valuable source of antioxidant-rich nutraceuticals.     

Mushroom extracts with antioxidant activity against lipid peroxidation

Methanol and water extracts, with antioxidant activity, from two edible mushrooms (Lentinus edodes and Volvariella volvacea) were subfractionated by liquid–liquid partition using organic solvents and by membrane ultrafiltration, respectively. The dichloromethane subfraction of the methanol extract of V. volvacea and the low molecular weight (LMW) subfraction of the water extract of L. edodes had the highest antioxidant activity against lipid peroxidation of rat brain homogenate with IC₅₀ values of 0.109 and 1.05 mg/ml, respectively. The ethyl acetate subfraction of the methanol extract of V. volvacea was found to have comparable antioxidant activity (p>0.05) to caffeic acid against the oxidation of human low-density lipoprotein (LDL). The antioxidant activities against lipid peroxidation in the above assays were found to correlate with the phenolic content in different subfractions of mushroom extracts.     

In vitro antioxidant, antimicrobial, and antitumor activities of bitter almond and sweet apricot (Prunus armeniaca L.) kernels

The aim of this study was to investigate in vitro antioxidant, antimicrobial, and antitumor activities of water, methanol, and ethanol extracts of sweet apricot and bitter almond kernels. The fruit extracts were evaluated for their antioxidant activities using various antioxidant methodologies including phosphomolybdenum assay (total antioxidant capacity), free radical scavenging assay, ferric ion reducing power, and β-carotene/linoleic acid bleaching test system. The antioxidant capacity of the sweet apricot kernels was better than those recorded for bitter almond ones. The highest total antioxidant activity (59.53 mg/g dry extract), ferric ion reducing power (1.626), antioxidant index (67%), total phenolic content (3.290 mg/g dry extract), and total lycopene content (4.70mg/mL) were detected in the aqueous extract of sweet apricot kernels. The antimicrobial activities of the above extracts were also tested against some pathogenic microorganisms using a disc-diffusion method. Additionally, the extracts of sweet apricot and bitter almond kernels could inhibit the growth of human breast (MCF-7), colon (HCT-116), and hepatocellular (Hep-G2) carcinoma cell lines in a dose-dependent manner with different sensitivity between cell lines. The overall results indicate promising baseline information for the potential uses of apricot (Prunus armeniaca L.) fruit extracts in the treatment of infectious diseases and tumors.     

Antioxidant activity of phenolic compounds from canola (Brassica napus) seed

The antioxidant activities of various extracts from canola (Brassica napus) seed were investigated using the DPPH assay, ABTS radical assay, and reducing power. An 80% methanol extract from canola seed was sequentially fractionated and separated according to the solvent polarity and Sephadex LH-20 chromatography, respectively. The antioxidant activities of various extracts and their total phenolic content (TPC) and total flavonoid content (TFC) were closely correlated, resulting in correlation coefficient values higher than 0.87. Of all extracts, the sub-fraction 3 had the highest TPC (462.3 μg/mg) and TFC (75.4 μg/mg) while it showed the lowest EC₅₀ value (183.1 μg/mL). The EC₅₀ value of sub-fraction 3 measured using the DPPH radical assay was 1.3 times lower than that of butylated hydroxytoluene (BHT). The major free phenolic compound was trans-sinapic acid (193.4 μg/mg) and sinapic acid derivatives identified as 1-O-β-d-glucopyranosyl sinapate and 1,2-di-O-sinapoyl-β-d-glucose in sub-fraction 3.     

Screening of the phenolic profile and their antioxidative activities of methanol extracts of <Emphasis Type="Italic">Myrica rubra</Emphasis> fruits,leaves and bark

The phenolic composition in dried Myrica rubra fruits, leaves and bark were investigated for evaluation of its contribution to the antioxidant activity. The fruits, leaves and bark have the abundant phenolic compounds with the total phenolic content of 0.673, 0.276 and 0.136 mg/g (GA equivalents/FW), respectively. Ten phenolic compounds were isolated and identified in methanol extracts of Myrica rubra fruits by GC–MS analysis. Less phenolic compounds were found in leaves and bark than in fruits. However, the leaves and bark contain much higher concentrations of the trans-resveratrol over 100 μg/g than in fruits. The total antioxidant activities against the ·DPPH radical of those three samples were 0.438, 0.184 and 0.092 mg/g (Trolox equivalents/FW), respectively. The quantitative results indicated that a good correlation between the total antioxidant activity, total phenolic contents, and abundance of individual phenolic compound in Myrica rubra plants.     

Radical scavenging and reducing properties of extracts of cashew shoots (Anacardium occidentale)

The total phenolic content and antioxidant activities of methanol, hexane and ethyl acetate extracts of the shoots of Anacardium occidentale were measured. Total phenolic content was assessed by the Folin–Ciocalteau assay whereas antioxidant activities were assessed by measuring the ability of the extracts to scavenge the ABTS^·+ and DPPH^· radicals, superoxide anion radicals and nitric oxide radicals as well as their ability to reduce ferric ions. Results indicated that the methanol extract of A. occidentale was the most potent reducing agent and radical-scavengers compared to the other two extracts. The ethyl acetate extract exhibited some antioxidant activities whereas the hexane extract is the least reactive. The order of the antioxidant potency of the plant extract is methanol > ethyl acetate > hexane. The methanol extract contained more than 7 fold of total phenolic content compared to the hexane and ethyl acetate extracts indicating the likely possibility that the observed antioxidant activities were partly contributed by the phenolics. The results suggest that the shoots of A. occidentale are a source of natural antioxidants.     

Antioxidant Properties and Phenolic Composition of Greek Propolis Extracts

This study was undertaken to determine the total phenols, total flavonoids, and major phenolic compounds in the polar (methanol, 80% methanol, and aqueous) extracts of propolis collected from the Greek mainland (West Macedonia) and the Greek island, Rhodes. The antioxidant properties of the propolis extracts were also evaluated by using free 2,2^′-diphenyl-1-picrylhydrazyl radical scavenging assay and ferric reducing antioxidant power assay. The results showed that propolis from West Macedonia was found to be the strongest radical scavenger and ferric reducing agent (mean IC₅₀ 0.179 and 0.009 mg/ml, respectively). Methanol (mean IC₅₀ 0.181 mg/ml) and 80% methanol extracts (mean IC₅₀ 0.138 mg/ml) of propolis from West Macedonia showed higher radical scavenging activity than the synthetic antioxidant butylated hydroxytoluene (mean IC₅₀ 0.207 mg/ml), while exhibiting similar levels of reducing activity (IC₅₀ 0.0099 mg/ml and 0.0085 mg/ml, respectively) with flavonol quercetin (mean IC₅₀ 0.0101 mg/ml). In addition, analysis by high performance liquid chromatography showed that West Macedonia propolis, contained the highest amount of phenolic compounds: phenolic acids (caffeic acid, caffeic acid phenethylester, ferulic acid, p-coumaric acid) and flavonoids (quercetin, galangin, luteolin, apigenin). Caffeic acid (0.639–4.172 mg/g propolis) and galangin (1.317–8.551 mg/g propolis) were found to be the predominant phenolic compounds in these propolis extracts.     

In vitro antioxidant activities of methanol extracts of five Phyllanthus species from India

In this study, the antioxidant activity of methanol extracts of five plants from the genus Phyllanthus was evaluated by various antioxidant assays, including total antioxidant, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, nitric oxide scavenging, reducing power and metal ion chelating activities. The various antioxidant activities were compared to standard antioxidants such as butylated hydroxytoluene and ascorbic acid. All the extracts showed strong antioxidant activity in all the tested methods. Among the five plants Phyllanthus debilis has been found to possess the highest activity in all tested models, the activity decreased in the order Phyllanthus debilis>Phyllanthus urinaria>Phyllanthus virgatus>Phyllanthus maderaspatensis>Phyllanthus amarus. In addition to the antioxidant activity of these plants, the total phenolic compounds, flavonoids and flavonols were measured in the extracts. A correlation between the antioxidant activity and total phenolic content was observed.     

Antioxidant activity and phenolic content of brick caps mycelium (Naematoloma sublateritium) extracts

A total of 5 subfractions were obtained from methanol extracts of N. sublateritium mycelia via systemic extraction using n-hexane, chloroform, ethyl acetate, n-butanol, and water. The trolox equivalent antioxidant capacity of the chloroform subfraction was 649.40 μmol/g of sample. The highest ferric reducing/antioxidant power (FRAP) assay value was found in the chloroform subfraction (299.24 μmol of FeSO₄·7H₂O/g). The chloroform and ethyl acetate subfractions exhibited the highest total phenolic compound contents, with ferulic acid equivalents of 31.66 and 48.57 mg/g, respectively. The phenolic acids in the subfractions were further identified using liquid chromatography-tandem mass spectrometry. The 5 phenolic acids of 4-hydroxybenzoic acid, α-resorcylic acid, 4-coumaric acid, salicylic acid, and gentisic acid were found to be the major phenolics in the mushroom.     

Antioxidant activities of Sideritis congesta Davis et Huber-Morath and Sideritis arguta Boiss et Heldr: Identification of free flavonoids and cinnamic acid derivatives

Different solvent extracts of endemic Sideritis (Labiatae) species, Sideritis congesta Davis et Huber-Morath and Sideritis arguta Boiss et Heldr, were analyzed for free flavonoids (quercetin, apigenin, myricetin and kaempferol) and cinnamic acid derivatives (rosmarinic acid, ferulic acid, caffeic acid, p-coumaric acid and chlorogenic acid) using HPLC-DAD. All the phenolics were quantified in acid-hydrolyzed extracts, except rosmarinic acid, chlorogenic acid and myricetin which were quantified in raw samples. Antioxidant activities of extracts of these two plants and many of their components in pure form were evaluated based on DPPH^. and ABTS^.+ assays. In general, S. arguta extracts displayed higher antioxidant activity than S. congesta extracts possibly due to their richness in antioxidant components of strong activity. Acetone extract of S. arguta, with its strikingly high TEAC value of 3.2 mM trolox and low IC₅₀ value of 38.3 ??g/mL showed the highest antioxidant potency among all extracts. ??-tocopherol, the positive control, displayed IC₅₀ and TEAC values of 33.8 ??g/mL and 2.9 mM trolox, respectively. No direct correlation was found between antioxidant activities and total phenolic contents of the plant extracts studied.     

Antioxidant and antiproliferative activities of mango (Mangifera indica L.) flesh and peel

The antioxidant and antiproliferative properties of flesh and peel of mango (Mangifera indica L.) were investigated. The cytoprotective effect of mango flesh and peel extracts on oxidative damage induced by H₂O₂ in a human hepatoma cell line, HepG2, were determined, and the underlying mechanism was examined by a single-cell electrophoresis assay (comet assay). Treatment of HepG2 cell with mango peel extract prior to oxidative stress was found to inhibit DNA damage. The free radical scavenging activities of mango flesh and peel extracts were evaluated by electron spin resonance (ESR). The mango peel extract exhibited stronger free radical scavenging ability on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and alkyl radicals than mango flesh extract, regardless of ripeness. Similarly, peel extract exhibited significant antiproliferative effect against all tested cancer cell lines, compared to that of flesh extract, in a dose-dependent manner. The result also showed that the antiproliferative activity of mango flesh and peel extracts correlated with their phenolic and flavonoid contents. Thus, mango peel, a major by-product obtained during the processing of mango product, exhibited good antioxidant activity and may serve as a potential source of phenolics with anticancer activity.     

Antioxidant activity of Mammea longifolia bud extracts

Mammea longifolia buds (nagkesar) are extensively used in India as a minor spice. The antioxidant activity of its methanol (NM) and aqueous-ethanol (NW) extracts were evaluated by several in vitro experiments, e.g., DPPH, hydroxyl, superoxide radicals and H₂O₂-scavenging assays as well as inhibition of Fe(II)-induced lipid peroxidation of rat liver mitochondria. The extracts were found to possess impressive antioxidant activity in all the tests, the activity of NW being higher than that of NM in most of the assays. The differential activities of NW and NM could be correlated with their respective total phenolic, flavonoid and proanthocyanidin contents.