Antioxidant and hepatoprotective activities of five eggplant varieties

Eggplant is consumed throughout the world and varies in fruit color, shape, and size. In this study, five varieties of eggplant (purple colored moderate size, white-green colored moderate size, long green, green striped moderate size and pale-green colored small size, respectively, called SM1–SM5) were evaluated for total phenolic and flavonoid content, antioxidant activity and hepatoprotection against cytotoxicity of tert-butyl hydroperoxide (t-BuOOH) in human hepatoma cell lines, HepG2. Total phenolic content found in methanol extracts of SM1–SM5 ranged from 739.36 ± 1.59 to 1116.13 ± 7.30 gallic acid equivalents mg/100 g extract and total flavonoid content from 1991.29 ± 6.32 to 3954.20 ± 6.06 catechin equivalents mg/100 g extract. SM1 and SM2 which contained high total phenolic and flavonoid had better antioxidant activities than the other varieties. Pretreatment of HepG2 cells with 50 and 100 μg/mL of SM1–SM5 significantly increased the viability (p < 0.05) of t-BuOOH-exposed HepG2 cells by 14.49 ± 1.14% to 44.95 ± 2.72%. The antioxidant activities of the eggplant were correlated with the total amounts of phenolic and flavonoid (r = 0.5310−0.7961). Significant correlation was found between hepatoprotective activities and total phenolic/flavonoid content (r = 0.6371–0.8842) and antioxidant activities (r = 0.5846–0.9588), indicating the contribution of the phenolic antioxidant present in eggplant to its hepatoprotective effect on t-BuOOH-induced toxicity.     

Biological activity assessment and phenolic compounds characterization from the fruit pericarp of Litchi chinensis for cosmetic applications

Context: Litchi chinensis Sonn. (Spindaceae) is an important economic fruit of Thailand. Therapeutic effects of the fruits are contributed by anti-inflammatory phenolics.

Objective: To extract the litchi fruit pericarp in order to identify biologically actives substances with potential for cosmetic application.

Materials and methods: The litchi pericarp was macerated by 70% ethanol (EtOH) and partitioned using n-hexane and ethyl acetate (EtOAc). In vitro antioxidant activities were assessed by 1, 1-diphenyl-2-picrylhydrazyl (DPPH), ABTS and ferric reducing ability of plasma (FRAP) assays including tyrosinase inhibitory effect. Cellular radical scavenging capacity was monitored in a normal human fibroblast cell culture (NHF). Total phenolic content was determined and characterized by HPLC.

Results: The EtOAc fraction was a significant antioxidant, stronger than ascorbic acid (p < 0.01), as assessed by ABTS (IC₅₀ = 7.137 ± 0.021 μg/mL), DPPH (IC₅₀ = 2.288 ± 0.063 μg/mL) and FRAP (EC_1mMFeSO4 = 8013.183 ± 58.804 μg/mL) assays. It demonstrated an antityrosinase effect (IC₅₀ = 197.860 ± 1.230 μg/mL) and showed no cytotoxic activity toward Vero and NHF cells, at a maximum tested concentration (50 μg/mL), with cellular antioxidant activity. Total phenolic content was highest in the most potent antioxidant fraction. Quercetin, rosmarinic and gallic acids were found. Total phenolic content is highly related to FRAP, antityrosinase, and ABTS activities.

Discussion and conclusion: Pericarp from litchi fruit can be obtained abundantly from agricultural waste, and the strong antioxidant activity demonstrated in this report may have application in topical cosmetic products. This ecological antioxidant can be prepared using a feasible method resulting in less waste and increased agro-industrial profitability.     

Inhibitory effects of ethyl acetate extract of Teucrium polium on in vitro protein glycoxidation

Regarding the involvement of free radicals and oxidative reactions in protein glycoxidation processes, compounds with antioxidant activities have been tested in order to reduce or to stop glycoxidation. In this study, we evaluated the antioxidant potential of several organic fractions of Teucrium polium extract using different model systems including total antioxidant capacity by the phosphomolybdenum method, ferric reducing antioxidant power and Trolox equivalent antioxidant capacity assays, antioxidant activity in linoleic acid emulsion system and scavenging of 1,1-diphenyl-2-picrylhydrazyl radical. The results indicated that the ethyl acetate (EtOAc) fraction of T. polium possesses the highest antioxidant activity and total phenolic and flavonoid contents. Given the link between glycation and oxidation, we proposed that the EtOAc fraction might possess significant in vitro antiglycation activities as well. Our data confirmed the inhibitory effect of EtOAc fraction on bovine serum albumin (BSA) glycoxidation measured in terms of advanced glycation end products (AGEs) and pentosidine formation as well as protein oxidation markers including protein carbonyl formation (PCO) and loss of protein thiols. Reducing sugars such as ribose and glucose increase fluorescence intensity of glycated BSA in terms of total AGEs and pentosidine during 21 day of exposure. Moreover, sugars cause more PCO formation and also oxidize thiol groups more in glycated than in native BSA. EtOAc extract at different concentrations (10–100 μg/ml) has significantly quenched the fluorescence intensity of glycated BSA. Furthermore, we demonstrated that the inhibitory effect of EtOAc extract in preventing oxidative protein damages including effect on PCO formation and thiol oxidation which are believe to form under the glycoxidation process. These results clearly demonstrate that, the EtOAc fraction, owning to its antioxidant content, is capable of suppressing the formation of AGEs and protein oxidation in vitro.     

Solanum torvum Swartz. fruit containing phenolic compounds shows antidiabetic and antioxidant effects in streptozotocin induced diabetic rats

In this study, quantification of phenolic compounds and the investigation of antidiabetic and antioxidant activities of the fruit of Solanum torvum Swartz. are described. S. torvum fruit methanol extract (STMe) was administered orally at a dose of 200 and 400 mg/kg/day to streptozotocin induced diabetic rats for 30 days. The levels of glucose, insulin, total protein, hemoglobin, glycated hemoglobin, liver glycogen and marker enzymes of carbohydrate metabolism, hepatic function and antioxidants were analyzed. High-performance liquid chromatography (HPLC) analysis revealed that STMe contained high levels of phenolic compounds, mainly rutin (1.36% w/w), caffeic acid (12.03% w/w), gallic acid (4.78% w/w) and catechin (0.46% w/w). STMe at 200 and 400 mg/kg reduced blood glucose level by 17.04% and 42.10%, respectively in diabetic rats. The levels and/or activities of other biochemical parameters were restored significantly compared to diabetic control rats due to treatment with fruit extract. Histology of liver and pancreas in STMe treated groups substantiated the cytoprotective action of the drug. Immunohistochemical observation of islets in extract treated diabetic rats showed apparent β-cells regeneration. These findings suggest that S. torvum fruit containing phenolic compounds has great potential as a natural source of antidiabetic and antioxidant drug.     

Evaluation of antioxidant,anti-inflammatory,and antiulcer properties of Vaccinium leschenaultii Wight: A therapeutic supplement

In folklore systems of medicine, bilberry fruit and leaf extracts have been used for the treatment of diarrhoea, dysentery, diabetes, inflammation, and ulcer. The present study was to determine antioxidant, anti-inflammatory, and antiulcerogenic activities of Vaccinium leschenaultii Wight leaf and fruit. The phenolic, tannin, and flavonoid contents of V. leschenaultii leaf and fruit were quantified and were subjected to assess their antioxidant potential using various in vitro systems such as 1, 1 diphenyl-2-picrylhydrazyl, 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging, phosphomolybdenum, and ferric reducing antioxidant power reduction activities. Based on the antioxidant potential, acetone and methanol extracts of leaf and fruit were used to evaluate the anti-inflammatory activity and protective effect against ethanol-induced gastric damage in a rat model. The quantification of secondary metabolites shows that the phenolic, flavonoid, and tannin contents are higher in methanol extracts of fruit and leaf. The results of antioxidant assays exhibited that the methanol extracts of leaf possesses better 1, 1 diphenyl-2-picrylhydrazyl radical scavenging and ferric reducing power activity. Oral administration of the acetone fruit and leaf extracts of V. leschenaultii were capable of reducing the edema formation in rats against carrageenan and egg albumin induced inflammation. Moreover, leaf and fruit acetone extracts at the dose of 400 mg/kg highly inhibited ulcer formation. The study concluded that the plant substances such as total phenols, flavonoids along with appreciable antioxidant potential could be the supportive evidence to prove both the anti-inflammatory and antiulcer activities of V. leschenaultii. The traditional importance of this plant will help to reveal the potential of plant to provide alternative phytotherapeutics for human health.     

Antioxidant and antiacetylcholinesterase activities of Sorbus torminalis (L.) Crantz (wild service tree) fruits

In this study, the antioxidant and antiacetylcholinesterase activities of Sorbus torminalis (L.) Crantz fruits were evaluated. Total phenolic and flavonoid compounds, 2,2′-azino-bis (3-ethylbenzothioazoline-6-sulfonic acid), 2,2′-diphenyl-1-picrylhydrazyl, and superoxide anion radicals scavenging activities and ferric-reducing antioxidant power of water, ethyl acetate, acetone, and methanol extracts were determined for the measurement of the antioxidant activity. Quercetin and α-tocopherol were used as standard antioxidants. The inhibitory effect of the water extract on acetylcholinesterase (AChE) was evaluated using the Ellman method and galantamine was used as a standard. Water extract had the highest total phenolic concentration and the strongest antioxidant activity followed by ethyl acetate and acetone extracts whereas methanol extract has the lowest phenolics and weakest antioxidant activity. Moreover, water extract showed moderate ability to inhibit AChE. It was concluded that fruits of S. torminalis have antioxidant and anti-AChE activities and that the plant might be a natural source of antioxidants and AChE inhibitors.     

Effect of extraction solvent on total phenol content,total flavonoid content,and antioxidant activity of Limnophila aromatica

Limnophila aromatica is commonly used as a spice and a medicinal herb in Southeast Asia. In this study, water and various concentrations (50%, 75%, and 100%) of methanol, ethanol, and acetone in water were used as solvent in the extraction of L. aromatica. The antioxidant activity, total phenolic content, and total flavonoid content of the freeze-dried L. aromatica extracts were investigated using various in vitro assays. The extract obtained by 100% ethanol showed the highest total antioxidant activity, reducing power and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity. The same extract also exhibited the highest phenolic content (40.5 mg gallic acid equivalent/g of defatted L. aromatica) and the highest flavonoid content (31.11 mg quercetin equivalent/g of defatted L. aromatica). The highest extraction yield was obtained by using 50% aqueous acetone. These results indicate that L. aromatica can be used in dietary applications with a potential to reduce oxidative stress.     

Phytochemical analysis and antioxidant activity of Lycium barbarum (Goji) cultivated in Greece

Context: The fruit of Lycium barbarum L. (Solanaceae), known as goji berry, has been exploited for a long time in traditional Chinese medicine. In recent decades, it has received much attention as one of the trendiest functional foods with a wide array of pharmacological activities in Western diets.

Objective: In this study the phenolic profile and potential antioxidant capacity of Lycium barbarum cultivated in Crete (Greece) were investigated.

Materials and methods: The berries were defatted with hexane and then extracted with dichloromethane and methanol using a Soxhlet apparatus. Furthermore, the methanol extract was fractionated with ethyl acetate and butanol. All fractions/extracts were tested for their antioxidant activity (DPPH, FRAP, chemiluminescence). Folin–Ciocalteu and LC-DAD-MS analyses were utilized for the identification of the phenolic compounds.

Results: The total phenolic content ranged from 14.13?±?0.40 (water fraction) to 109.72?±?4.09 (ethyl acetate fraction) mg gallic acid equivalent/g dry extract. Ethyl acetate extract exhibited the highest scavenging activities determined as EC₅₀ (4.73?±?0.20?mg/mL) and IC₅₀ (0.47?±?0.001?mg/mL) using DPPH and chemiluminescence assays. Seventeen phenolic compounds, including cinnamoylquinic acids and derivatives, hydrocinnamic acids and flavonoid derivatives, were tentatively identified. To the best of our knowledge, quercetin 3-O-hexose coumaric ester and quercetin 3-O-hexose-O-hexose-O-rhamnose are reported for the first time in goji berry fruits.

Discussion and conclusion: The results of this study suggest that consumption of goji berry fruits could serve as a potential source of natural antioxidant compounds and that goji berry phenolic extracts could be exploited for nutritional pharmaceutical purposes.     

Evaluation of In Vitro Antioxidant Potential of Cordia retusa

The present study was carried out to investigate the antioxidant potential, total flavonoid and phenolic content in extracts of aerial parts of Cordia retua (Vahl.) Masam. The samples such as ethyl acetate and ethanol extracts were tested using six in vitro models such as 2,2-diphenyl-1-picrylhydrazyl, nitric oxide radical, iron chelating, hydroxyl radical, superoxide radical scavenging activity and total antioxidant activity to evaluate the in vitro antioxidant potential of C. retusa by spectrophotometrically. Total flavonoid and phenolic content in samples were estimated using aluminum chloride colorimetric and Folin-Ciocalteu method. The results were analyzed statistically by the regression method. Half maximal inhibitory concentration (IC₅₀) of the ethanol extract was found to be 596 μg/ml for DPPH, 597 μg/ml for nitric oxide radical, 554 μg/ml for iron chelating, 580 μg/ml for hydroxyl radical, 562 μg/ml for superoxide radical and 566 μg/ml for total antioxidant capacity. Furthermore, the total flavonoid content and total phenolic content of the ethanol extract were found to be 2.71 mg gallic acid equivalent per gram of extract and 1.86 mg quercetin equivalent per gram of extract, respectively. In all the testing, a significant correlation existed between concentrations of the extract and percentage inhibition of free radicals. The results of the present comprehensive analysis demonstrated that C. retusa possess potent antioxidant activity, high flavonoid and phenolic content. The antioxidant property may be related to the polyphenols and flavonoids present in the extract. These results clearly indicated that C. retusa is effective against free radical mediated diseases as a natural antioxidant.     

Antioxidant and antimicrobial capacity of several monofloral Cuban honeys and their correlation with color,polyphenol content and other chemical compounds

Several monofloral Cuban honeys were analyzed to determine their total phenolic, flavonoid, ascorbic acid, amino acid, protein and carotenoid contents as well as their radical-scavenging activity and antimicrobial capacities. The total phenolic, flavonoid and carotenoid contents varied considerably, and the highest values were obtained for Linen vine (Govania polygama (Jack) Urb) honey, which is classified as an amber honey. The highest amino acid content was found in Morning glory (Ipomoea triloba L.) while Liven vine had the highest protein content. Similarly Linen vine honey had the highest antioxidant activity while the lowest was found in Christmas vine (Turbina corymbosa (L.) Raf). Ascorbic acid was absent. Hydroxyl radical formation was studied by EPR and spin trapping, and it was found in all honeys tested. The antimicrobial activity was screened using two Gram-positive and Gram-negative bacteria. S. aureus was the most sensitive microorganism while Pseudomonas aeruginosa presented higher minimum active dilution values. Bacillus subtilis and Escherichia coli were both moderately sensitive to honey antimicrobial activity. A correlation between radical-scavenging activity and total phenolic content was found. Correlation existed also between color vs phenolics content, vs flavonoid content or between phenolic vs flavonoid.     

Flavonoid compositions and antioxidant activity of calamondin extracts prepared using different solvents

Calamondin has been demonstrated to exhibit antioxidant function and tyrosinase inhibitory activity, which might be attributed to its flavonoid compounds. To improve their application, the flavonoid compositions and antioxidant activity of calamondin extracts, prepared by different solvents, were investigated. The results showed that total phenolic and flavonoid contents of extracts from peel of calamondin were higher than that from pulp, except the flavonoid content in hot water extract. The flavonoids found in extracts of calamondin were 3′,5′-di-C-β-glucopyranosylphloretin (DGPP), naringin, hesperidin, nobiletin, tangeretin, and diosmin. DGPP exhibited the highest quantity, while naringin and hesperidin were the other two major flavonoids. The content of DGPP in hot water extract of peel was higher than in extracts of organic solvents, however, the contents of nobiletin and tangeretin were found only in extracts of organic solvents. The highest levels of total flavonoids and DGPP were obtained in hot water extract from peel at 90°C. The extracts of hot water and ethyl acetate showed higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging potency than that of ethanol and methanol. A positive relationship existed between total phenolic contents and DPPH scavenging potency (p < 0.01), while total flavonoid compositions also showed correlation (p < 0.05). Thus, DGPP, naringin, and hesperidin might contribute to antioxidant activity. Collectively, the hot water extract of calamondin peel might have potential for health food and cosmetic applications due to its good antioxidant activity and high level of DGPP.     

Characterization of increased phenolic compounds from fermented Bokbunja (Rubus coreanus Miq.) and related antioxidant activity

This study examined the changes in the phenolic acid-content and antioxidant activity of Rubi Fructus (RF), the fruit of Rubus coreanus Miq., after fermentation with yeast (Saccharomyces cerevisiae). The phenolic acids were fractionated into three forms, free (Fr. A), ester (Fr. B), and insoluble-bound phenolic acids (Fr. C) and quantified by high performance liquid chromatography with a diode array detector (HPLC-DAD). This method was validated and allowed the successful identification of 11 phenolic acids in the RF extracts. HPLC-DAD analysis of the samples showed substantial increases in the levels of protocatechuic, vanillic and p-coumaric acid as the result of yeast fermentation. The total phenolic content (TPH) was also increased by fermentation. The total phenolics in Fr. A and Fr. B increased from 117 to 173 mg GAE/100 g and from 488 to 578 mg GAE/100 g, respectively. The total phenolics in Fr. C decreased from 264 to 175 mg GAE/100 g. The antioxidant activity of the fermented RF was measured as the 1,1-diphenoly-2-picrylhydrazyl (DPPH) radical scavenging capacity, which is expressed as the IC₅₀. The IC₅₀ for Fr. A and Fr. B decreased from 5.9 to 4.0 mg/ml (mg of dried RF equiv./ml) and from 1.2 to 0.8 mg/ml, respectively. In Fr. C, the IC₅₀ value increased from 2.1 to 2.8 mg/ml. In summary, the fermented RF had a higher total phenolic content and better DPPH radical-scavenging activity than the unfermented material.     

Identification of non-alkaloid natural compounds of Angelica purpurascens (Avé-Lall.) Gilli. (Apiaceae) with cholinesterase and carbonic anhydrase inhibition potential

In current study is done antioxidant, anticholinesterase, and carbonic anhydrase isoenzymes I and II inhibition assays, screening of biological active compounds and electronic microscopy analysis of secretory canals of fruits, flowers, roots, and aerial parts extracts and essential oils of Angelica purpurascens. Phenolic constituents, antioxidant, and anti-lipid peroxidation potentials of variants were estimated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and thiobarbituric acid (TBA) processes. Cholinesterase inhibition effect was detected through Ellman’s method. The GC/ Mass Spectrometry (MS) and gas chromatography (GC)-flame Ionization Detector (FID) was used for essential oils analysis. NMR techniques was used for identification of the isolated compounds. The fruit hexane and dichloromethane fractions exhibited a greater antioxidant capacity and total phenolic content. The dichloromethane fraction of fruit demonstrated the most higher acetylcholinesterase inhibition (39.86 ± 2.63%), while the fruit hexane fraction displayed the best inhibition towards butyrylcholinesterase (84.02 ± 1.28%). Cytosolic isoenzymes of human carbonic anhydrase (hCA) I, and II isoenzymes were influentially suppressed by flower and fruit dichloromethane fractions with 1.650 and 2.020 µM IC₅₀ values, respectively. The electronic microscopy analysis of secretory canals found that the small number of secretory canals were at leaf while the largest shape of secretory canals was at the fruit. The secretory canals of roots, aerial parts, and fruits include more monoterpene hydrocarbons, while the canals, existing in the flowers are qualified by a higher presence of sesquiterpenes β-caryophyllene (12.1%), germacrene D (4.5%) and ether octyl acetate (11.9%). The highest level of monoterpene β-phellandrene (47.6%) and limonene (8.2%) were found in the fruit essential oil. The next isolated compounds from fruits of A. purpurascens like stigmasterol, β-sitosterol, bergapten, and oxypeucedanin have shown high anticholinesterase and antioxidant activities.     

Inhibitory effects of Nelumbo nucifera leaves on rat lens aldose reductase, advanced glycation endproducts formation, and oxidative stress

The preventive and therapeutic potency against oxidative stress and diabetic complications of Nelumbo nucifera were evaluated via the 1,1-diphenyl-2-picrylhydrazyl (DPPH), Trolox equivalent antioxidant capacity (TEAC), and total reactive oxygen species (ROS) assays, as well as the rat lens aldose reductase (RLAR) and advanced glycation endproducts (AGE) assays. The leaf extract of N. nucifera exerted potent antioxidant effects as well as marked inhibitory effects for RLAR and AGE formation, corresponding to high values for total phenolic content (TPC) and total flavonoid content (TFC). Among several solvent fractions, the EtOAc and n-BuOH fractions, having prominent TPC and TFC values, showed significant antioxidant effects in the DPPH and TEAC assays. Moreover, the EtOAc fraction exhibited superior inhibitory effects in the total ROS, RLAR, and AGE assays, with IC₅₀ values of 9.4, 2.4, and 28.2 μg/ml, respectively. Also, the HPLC profiles of the active EtOAc fraction indicated that quercetin 3-O-β-d-glucopyranoside (Qc-3-Glc) and Qc 3-O-β-d-glucuronopyranoside (Qc-3-Gln) were two of its major components, as well as Qc 3-O-β-d-galactopyranoside (Qc-3-Gal) as a minor compound. Therefore, the results suggest that two key antioxidant flavonoids, Qc-3-Glc and Qc-3-Gln, may play important roles in the antioxidant and RLAR inhibitory effects of N. nucifera leaves. Also, the leaves, and the flavonoids contained within them, would clearly have potential uses in the development of therapeutic or preventive agents for diabetic complications and oxidative stress-related diseases.     

Investigation of the extracts from Bidens pilosa Linn. var. radiata Sch. Bip. for antioxidant activities and cytotoxicity against human tumor cells

The aim of this study was to evaluate antioxidant activities and cytotoxicity against human tumor cell lines of extracts from Bidens pilosa Linn. var. radiata Sch. Bip. (BP). Total phenolic and flavonoid contents of the extracts were determined by ultraviolet spectrophotometry. Furthermore, the antioxidant properties of different polarity fractions extracted from BP were evaluated using DPPH and ABTS radical scavenging test and FRAP assay. The ethyl acetate fraction (EE-BP) showed the highest antioxidant activity compared to other fractions. In addition, the anti-proliferative activities of the extracts on four human tumor cells, namely MCF-7, HepG2, MGC 803 and RKO, were investigated by MTT method. The EE-BP displayed the most remarkable anti-proliferative effect against the tumor cells, particularly RKO cell in dose- and time-dependent manner. The antioxidant activities and cytotoxicity correlated highly with the total phenolic and flavonoid contents, respectively. Furthermore, The active ingredient BP-6, namely 5,7,4??-trihydroxy-3,3??-dimethyl-flavonol, was isolated and purified with the purity above 99.00% and content of 0.15% in EE-BP detected by HPLC, which could significantly inhibit the proliferation of RKO cells with the IC₅₀ value of 6.66???mol/l. In order to characterize the apoptotic RKO cells, flow cytometry and DNA fragmentation assay were performed. Apoptotic cell numbers increased in a dose-dependent manner after the treatment with different concentrations of EE-BP and BP-6 for 12 and 6?h, respectively. DNA ladders in apoptotic RKO cells could be easily visualized when exposed to 200???g/ml of the EE-BP for 36?h. Taken together, our work indicated that BP had potentially therapeutic value against colorectal cancer.     

Antioxidant and antimicrobial properties of Moltkia petraea (Tratt.) Griseb. flower,leaf and stem infusions

Antioxidant and antimicrobial activities as well as the quantity of phenolic substances (total phenol, flavonoid and phenolic acid contents) were determined in aqueous extracts of leaves, stems and flowers of Moltkia petraea (Tratt.) Griseb. from two mountainous localities (Sveti Jure and Snije?nica) in Croatia. In addition, the profile of phenolic acids was analyzed by UPLC–MS/MS. Antioxidant activities of all extracts in different test systems, namely the DPPH radical scavenging, reducing power assay and chelating activity, increased with extract concentration. Activity of the extracts from Snije?nica in β-carotene-linoleic acid assay did not differ from the activity of standard, BHA. The leaf extracts from Snije?nica demonstrated superior antioxidant activity in most of the assays, while the stem extract from the same locality was the most effective Fe²⁺ ion chelator. In general, the extracts from Snije?nica were more effective antioxidants than the corresponding extracts from Sveti Jure. The aqueous extracts of M. petraea did not show antimicrobial activity against bacteria and fungi tested in the diffusion and dilution assays.     

A comparative study on the in vitro antioxidant potentials of three edible fruits: Cornelian cherry,Japanese persimmon and cherry laurel

This study was designed in order to investigate in vitro antioxidant potentials of 80% methanolic extracts prepared from three edible fruits, Cornus mas L., Diospyros kaki L., Laurocerasus officinalis Roem. For this purpose, 8 different tests were performed including 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radical scavenging tests, ferric reducing antioxidant power (FRAP), cupric reducing antioxidant capacity (CUPRAC), metal-chelating capacity, determination of total antioxidant capacity, β-carotene bleaching test in a linoleic acid emulsion system and trolox equivalent antioxidant capacity. In addition, for evaluating the phenolic profile, total phenolic, flavonoid and proanthocyanidin contents were measured spectrophotometrically. Among the three fruits analyzed, Diospyros kaki L. showed the highest activity in all tests, except β-carotene bleaching test. Whereas, neither of three fruits showed metal-chelating activity. Also, a good correlation was found between the phenolic content and antioxidant parameters.     

Antioxidant and hepatoprotective effects of Schisandra chinensis pollen extract on CCl4-induced acute liver damage in mice

The aim of the present study was to investigate the antioxidant and hepatotective effects of Schisandra chinensis pollen extract (SCPE) on CCl₄-induced acute liver damage in mice. Total phenolic content, total flavonoid content, individual phenolic compounds and antioxidant activities (1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, chelating activity, and reducing power assay) were determined. In vivo study, SCPE (10, 20 and 40 g/kg) administered daily orally for 42 days prior to CCl₄-intoxicated. Our results showed that SCPE had high total phenolic content (53.74 ± 1.21 mg GAE/g), total flavonoid content (38.29 ± 0.91 mg Rutin/g), quercetin and hesperetin may be the major contributor to strong antioxidant activities. Moreover, SCPE significantly prevented the increase in serum ALT and AST level in acute liver damage induced by CCl₄, decreased the extent of malondialdehyde (MDA) formation in liver and elevated the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in liver. The results indicated that SCPE has strong antioxidant activities and significant protective effect against acute hepatotoxicity induced by CCl₄, and have been supported by the evaluation of liver histopathology in mice. The hepatoprotective effect may be related to its free radical scavenging effect, increasing antioxidant activity and inhibiting lipid peroxidation.     

Phenolic composition,antioxidant and anti-acetylcholinesterase activities of the Tunisian Scabiosa arenaria

Abstract

Context: There is a need for the discovery of novel natural antioxidants and acetylcholinesterase inhibitors (AChEIs) that are safe and effective at a global level. This is the first study on antioxidant and anti-acethylcholinesterase activity of Scabiosa arenaria Forssk (Dipsacaceae).

Objective: The antioxidant potential and anti-acetylcholinesterase (AChE) activity of S. arenaria were investigated.

Material and methods: The crude, ethyl acetate (EtOAc), butanol (n-BuOH) and water extracts prepared from flowers, fruits and stems and leaves of S. arenaria were tested to determine their total polyphenol content (TPC), total flavonoid content (TFC), total condensed tannin content (CTC) and their antioxidant activity by using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), reducing power and β-carotene bleaching inhibition activity. Anti-AChE activity was also determined.

Results: EtOAc and n-BuOH fractions of fruits had both the highest (TPC) (269.09?mg gallic acid equivalents/g dry weight). The crude extract of stems and leaves had the highest TFC (10.9?mg quercetin equivalent/g dry weight). The n-BuOH fraction of stems and leaves had the highest CTC (489.75?mg catechin equivalents/g dry weight). The EtOAc fraction of flowers exhibit a higher activity in each antioxidant system with a special attention for DPPH assay (IC₅₀?=?0.017?mg/mL) and reducing power (EC₅₀?=?0.02?mg/mL). The EtOAc and n-BuOH fractions of stems and leaves showed strong inhibition of AChE (IC₅₀?=?0.016 and 0.029?mg/mL, respectively).

Discussion and conclusions: These results suggest the potential of S. arenaria as a possible source of novel compounds and as an alternative antioxidant and AChEIs.