DPPH Scavenging Activity Assay Research Articles

Phytochemical Analysis and Antioxidant, Antimicrobial, and Antibiofilm Effects of a New Himalayan Lichen Placidium deosaiense Usman and Khalid Growing in Pakistan

Phytochemical composition and antimicrobial, antibiofilm, and antioxidant effects of a newly described Himalayan lichen Placidium deosaiense Usman and Khalid growing in Pakistan were investigated. HPLC–DAD methods were used for identification of secondary metabolites in acetone and methanol extracts. The total phenolics content was measured using a spectrophotometric method. The study investigated the antioxidant (DPPH-scavenging activity assay and reducing-power assay), antibacterial (minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC)), and antibiofilm (inhibition of biofilm formation and reduction in mature biofilm) activities of extracts of the lichen P. deosaiense and isolated parietin. The chemical constituents olivetol, olivetolic acid, haematommic acid, fallacinol, and parietin were identified as major compounds in the tested extracts of the lichen. Parietin was isolated from the acetone extract on a separation column. The methanol extract had higher values of TPC (21.67 mg GAE/g) than the acetone extract. Isolated parietin showed the best antioxidant activity measures, according to the DPPH-scavenging activity assay (IC50 = 51.616 μg/mL) and reducing-power assay. Although the extracts showed the best antibacterial activity (especially against Proteus mirabilis ATCC 12453), parietin demonstrated superior antibiofilm activity (especially against Staphylococcus aureus ATCC 25923). This is the first report on the phytochemical composition of the lichen Placidium deosaiense and the first description of the chemical composition of some of the 45 species of the genus Placidium. This research will pave the way for further exploration of new activities of this lichen and its metabolites, which are important for medicine and pharmacy.

Comparison of Chemical Composition and Antioxidant Activity of Extracted Zingiberaceae Rhizome using Subcritical Water Extraction

In Malaysia, many local herbs can take advantage of their benefit for health products, cosmetics, and food production. In this research, fresh Zingiberacea rhizomes including Curcuma Longa, Curcuma Zedoaria, Curcuma Xanthorrhiza, Zingiber Officinale, and Zingiber Zerumbet rhizomes were extracted using the subcritical water extraction (SWE) unit located at AM Zaideen Ventures Sdn Bhd in Kuala Lumpur (Malaysia). The focus of this research is to analyze the freeze-dried powder extracts from the fresh Zingiberaceae rhizome for the phytochemical screening and bioactive compounds. Operating parameter used in the extraction process was fixed at temperature of 110°C, pressure at 10 bar and extraction time of 15 minutes. The freeze-dried powder extracts were screened for its phytochemicals inclusive alkaloids, steroids, terpenoids, glycosides, tannin and saponin. For bioactive compounds analysis, extracts were evaluated for Total Phenolic Content, Total Flavonoid Content, DPPH scavenging activity assay, and bioactive compound using Gas-Chromatography Mass Spectrophotometry analysis. The results show that there was a different presence of phytochemicals compounds in different Zingiberaceae extracts. At 10mg/ml concentration of powder extract, Zingiberaceae rhizomes showed variations in total phenol and flavonoid content, ranging from 134.65 to 285.19 mg GAE/g and from 22.58 to 181.62 mg QE/g, respectively. For DPPH radical scavenging activity, observed at 10mg/ml of freeze-dried extract, all Zingiberacea demonstrated significance antioxidant activity of more than 85% inhibition. Bioactive compounds detected in Zingiberaceae rhizomes shows significance quality. This finding supports the exploration of indigenous herbs market in Malaysia and the potential of water-based extracts on fresh Zingiberaceae rhizomes.

Active Thermoplastic Starch Film with Watermelon Rind Extract for Future Biodegradable Food Packaging.

Petrochemical plastic wastes generate serious environmental problems because they are resistant to natural decomposition. The aim of this study was to develop a biodegradable active thermoplastic film composed of polyvinyl alcohol (PVA), corn starch (ST), glycerol, and the active compounds from watermelon rind extract (WMRE), or PVA/ST/WMRE, using the casting technique. The film was examined for its mechanical, antioxidant, and functional properties against selected foodborne pathogens. The results showed that the addition of 10% v/v of watermelon rind extract to the film formulation significantly increased the tensile strength from 19.44 ± 0.84 MPa to 33.67 ± 4.38 MPa and slightly increased the percent elongation at break (% EAB) from 35.04 ± 0.96% to 35.16 ± 1.08%. The antioxidant property of PVA/ST/WMRE film was analyzed based on the DPPH scavenging activity assay, which significantly increased from 29.21 ± 0.24% to 63.37 ± 4.27%. The minimum inhibitory concentration (MIC) of watermelon rind extract was analyzed for the growth inhibition of Bacillus cereus ATCC 11778, Escherichia coli ATCC 8739, and Salmonella enterica subsp. enterica serovar Typhimurium ATCC 13311, with 10% (v/v) found as an optimal concentration against B. cereus. Wrapping fresh-cut purple cabbage with PVA/ST/WMRE film significantly reduced the microbial load after 3 days of storage, in comparison to commercial packaging (PET) and thermoplastic control film. Consumer testing of the packaging film indicated that user acceptance of the product was favorable. Therefore, we suggest that this newly developed film can be used as a biodegradable food packaging item that will lead to enhanced food safety, food quality, prolonged shelf life, and consumer acceptance for further food applications.

Bioactive peptide production and determination of functional properties using crude water extracts of Ulva lactuca (Chlorophyta) and Sargassum crassifolium (Phaeophyceae) collected from Sri Lanka

ABSTRACT Bioactive peptides of marine macroalgae consist of various functional properties. Ulva lactuca and Sargassum crassifolium are economically important, abundant green and brown macroalgae species in Sri Lanka that are rich in bioactive and functional components. However, few studies have been conducted to identify these bioactive and functional components of seaweeds in the local context. The aim of this study was to determine the best method to generate bioactive peptides from crude water extracts of Ulva lactuca and S. crassifolium and determine the functional properties of their hydrolyzates. Crude proteins of U. lactuca (sample: deionized water, 1:4) and S. crassifolium (sample: deionized water, 1:3) were extracted with water, using previously developed method and then subjected to protein hydrolysis by using papain (65°C, pH 6.00–7.00), α-chymotrypsin (37°C, pH 7.00–8.00), elastase (25°C, pH 8.0–8.50), and protease (60°C, pH 6.50–8.50) enzymes (1:100) under their optimum pH and temperatures for 0, 3, 6, 9, 12, 24 hours followed by heat inactivation at 100°C for 15 min. The best enzyme treatment was selected by conducting 15% SDS PAGE. Accordingly, proteins treated with enzymes followed by heat inactivation at 100°C for 15 min were selected as the best after considering the SDS-PAGE images. These hydrolyzates were used to determine the antioxidant activity (DPPH scavenging activity assay) and metal chelating activity (ferrozine method). Apart from peptides generated by elastase, all protein hydrolyzates had strong antioxidant activity (p < 0.05), but hydrolyzates produced from both crude extracts using α-chymotrypsin exhibited low Fe2+ chelating activity (p < 0.05) while some showed metal releasing activity. Therefore, protein hydrolyzates produced from U. lactuca using papain, protease, and α-chymotrypsin, followed with heat inactivation showed strong antioxidant activity while having very low Fe2+ chelating activity than all protein hydrolyzates of S. crassifolium. Highlights Ulva lactuca and Sargassum crassifolium are promising marine algal resources found in Sri Lankan waters to produce bioactive peptides. Enzymatic hydrolysis can be carried out with different enzymes as papain, α-chymotrypsin, protease, and elastase enzymes under their optimum temperature and pH conditions to produce bioactive peptides. The crude peptides showed high DPPH radical scavenging activities but low Fe2+ chelating activity.

Chemical Composition and Antiproliferative and Antioxidant Activities of Essential Oil from Juniperus phoenicea L. Cupressaceae

Being multipurpose, relatively safe, and widely favorable for consumption, interest in the essential oils of medicinal plants has been increasing. Essential oil (EO) of Juniperus phoenicea is traditionally used for treatment of several health problems such as diabetes, rheumatism, and cancer that is the second leading cause of death in Jordan. This study aims to collect and chemically analyze EO from Juniperus phoenicea L., from Jordan and to evaluate its cytotoxic and antioxidant activity against human breast cancer cells (T47D), colorectal adenocarcinoma cells (CACO2), and normal human fibroblasts (MRC5). EO was extracted by hydro-distillation and analyzed in a gas chromatograph coupled with a mass spectrometer. Cell viability was assessed using trypan blue, neutral red, and MTT assays, and antioxidant activity was evaluated using DPPH scavenging activity assay. Chemical composition analysis revealed 23 constituents in the EO, and the amount of α- pinene was the highest (69.71%). The results also revealed that the IC50 values of the viability assays were higher among normal cells compared to the human cancer cell lines, and the viability inhibition was significant at higher concentrations compared to untreated cells. Nevertheless, low antioxidant activity was observed for the oil in the DPPH scavenging activity test. To sum up, this study indicates that Jordanian Juniperus phoenicea EO, albeit unlikely to be an effective antioxidant, is optimistically potential to be utilized in breast and colon cancers treatment due to its preferential cytotoxicity against cancer cells.

Chemical Composition and Antiproliferative and Antioxidant Activities of Methanolic Extract of Alcea setosa A. Malvaceae

Alcea setosa A. (Malvaceae) is a wild plant that grows in Jordan and have several traditional medicinal uses. This study aims to collect and chemically analyze the methanolic extract from Alcea setosa A. from Jordan and to evaluate its cytotoxic and antioxidant activity against human breast cancer cells (T47D), colorectal adenocarcinoma cells (CACO2), and normal human fibroblasts (MRC5). The extract was extracted by methanol solvent and analyzed by liquid chromatography coupled with a mass spectrometer. Cell viability was assessed using trypan blue, neutral red, and MTT assays, and antioxidant activity was evaluated using DPPH scavenging activity assay. A total of 290 compounds, 12 among which were identified when compared to available standards, the extract contained six flavons derivatives, Two fatty acids, one ketone derivative, one flavonol derivative, one organic acid, and one coumarin derivative. The results also revealed that the IC50 values of the viability assays were higher among normal cells compared to the human cancer cell lines, and the viability inhibition was significant at higher concentrations compared to untreated cells. Nevertheless, moderate antioxidant activity was observed for the extract in the DPPH scavenging activity test. To sum up, this study indicates that samples of A. setosa collected from Jordan is likely to be an effective antioxidant, is optimistically potential to be utilized in breast and colon cancers treatment due to its preferential cytotoxicity against cancer cells.

Targeted Isolation of Antioxidant Constituents from Plantago asiatica L. and In Vitro Activity Assay.

Plantago asiatica L. is widely distributed in Eastern Asia and a commonly used drug in China, Korea, and Japan for diuretic and antiphlogistic purposes. In this experiment, the present study was performed to isolate antioxidant molecules based on the DPPH scavenging activity assay and discover the bioactive compounds which contributed to performing the function of Plantago asiatica L. Each faction was chosen for further isolation guided by DPPH scavenging activity assay. Afterwards, two potential bioactive molecules, aesculetin and apigenin, were isolated for in vitro antioxidant activity in cells. Hydrogen-peroxide-induced oxidative stress led to decreased cell viability, impaired intercellular junction, and damage to the cell membrane and DNA. Furthermore, aesculetin ameliorated decreased cell viability induced by hydrogen peroxide via upregulation of antioxidant related genes, and apigenin also protected against H2O2 mainly by improving the glutathione (GSH) antioxidant system, such as increasing the activity of glutathione peroxidase (GPX), glutathione reductase (GR), and the ration of GSH/glutathione disulfide (GSSG). Above all, these findings suggest that aesculetin and apigenin may be bioactive compounds for antioxidant function in Plantago asiatica L.

Pharmacognostical, Phytochemical, Antioxidant and Antimicrobial Activity of Costus woodsonii

Background: Herbal medicine mostly contains wide range of chemical compounds responsible for medicinal therapeutic use. Costus woodsonii is commonly called as Red Button Ginger and synonyms of the botanical name are Costus spiralis, Alpinia spiralis and Costus pisonis. In Malay, it is known as Setawar Halia Merah. In Chinese, it is known as Hong Bi Qiao Jiang. Objective: This research was conducted to study the pharmacognostical, phytochemical, antioxidant and antimicrobial activity of C. woodsonii leaf extracts. Method: Macroscopy, microscopy, phytochemical analysis, thin layer chromatography, antioxidant activity and antimicrobial activity of C. woodsonii leaf were carried out. Total flavonoids were estimated in the leaf extract. The total phenolic content of C. woodsonii leaf was determined using Folin-Ciocalteu reagent. The antioxidant activity of leaf extract of C. woodsonii was determined by performing DPPH radical scavenging. The microbial activity was determined by Well diffusion test, MIC (Minimum Inhibitory Concentration) test and MBC (Minimum Bactericidal Concentration) test. Result and Discussion: C. woodsonii belongs to costaceae with elliptical green leaves. Till now are no extensive studies on C. woodsonii. Preliminary phytochemical analysis revealed the presence of flavonoid, steroid, fat, phenol, tannin and mucilage in leaf extract. Physicochemical studies further revealed the ash value of leaf as 8.7%. Among the three extractions, alcohol extractive values showed the highest as 13%. Loss on drying at 105 degree Celsius in leaf was found to be 12.67%. The plant extract showed total phenolic content of 7.941 mg GAE/g at concentration of 5µg/ml. As for flavonoids content, plant extract showed 21.7 mg RE/g at concentration of 200µg/ml and 43.4 mg RE/g at concentration of 400µg/ml. For antioxidant activity, the plant extract showed weak antioxidant activity in DPPH scavenging activity assay. For antimicrobial test, the leaf extract of C. woodsonii showed weak antimicrobial activity. Conclusion: From this study, it can conclude that C. woodsonii leaf extract possess weak antioxidant activity and weak antimicrobial activity which need to be further validated by using more antioxidant assays and antimicrobial tests.

Comparison of Antioxidant and Anti-Tyrosinase Activities of Pineapple (Ananas comosus) Core Extract and Luteolin Compound

Free radicals and UV exposure can cause aging. Aging prevention needs substances that can prevent molecular oxidation reactions in cells and inhibit the activity of enzymes that trigger aging. Research on pineapple skin and flesh extract (Ananas comosus (L.) Merr.) reported the presence of luteolin compound which functions as antioxidants and antityrosinase. However, in this study, the object used was pineapple core extract (PCE), which has not been widely known for its antioxidant and antityrosinase activity. Therefore, the purpose of this study was to determine the content of phytochemical compounds, antioxidant activity, and inhibitory activity of tyrosinase enzymes by PCE and then compared with the luteolin (LT) compound test results using Fansworth method, DPPH scavenging activity assay and tyrosinase enzyme inhibition assay. Based on the study results, the phytochemical compounds contained in PCE were tannins and triterpenoids. PCE and LT produced the highest DPPH scavenging activity, which was 64.86% and 59.32% (final concentration 200μg/ml and 6.25μg/ml) and the highest tyrosinase inhibition activity, which was 60.52% and 85.02% (final concentration 100 μg/ml). Antioxidant activity was determined based on IC50 of 87.46µg/mL and 4.17 µg/ml respectively. IC50 tyrosinase enzyme inhibition EBN and LT respectively at 62.27µg/ml and 5.25 µg/ml. Antioxidant activity through DPPH free radical scavenging test and tyrosinase enzyme inhibition activity by PCE was lower than LT.

Phytochemical Characterization of Five Edible Purple-Reddish Vegetables: Anthocyanins, Flavonoids, and Phenolic Acid Derivatives.

Vegetables comprise a significant portion of our daily diet with their high content in nutrients including fiber, vitamins, minerals, as well as phenolic compounds. Vegetable consumption has been shown to be positively associated with the prevention of several degenerative diseases thanks to their bioactive compounds. Accordingly, five selected vegetables, namely, red chicory, red onion, eggplant, purple sweet potato, and black carrot were thoroughly assessed for their phenolic content in this study. For this purpose, the total phenolic and flavonoid content of these five vegetables and their antioxidant activities that are based on three common methods ABTS radical cation decolorization assay (ABTS), Cupric Ion Reducing Antioxidant Capacity (CUPRAC), and DPPH scavenging activity assay were determined. Additionally, HPLC-PDA/Electrospray ionization coupled with mass spectrometry (HPLC-PDA/-ESI+-MS)-based identification and quantification of the members belonging to polyphenols present in each vegetable were determined. Statistical correlations between antioxidant activities and the specific type of phenolic compounds, such as anthocyanins, flavonoids, anthocyanins, and phenolic acids were further elucidated. Phenolic acids (chlorogenic and syringic acids) were found to be the most abundant compounds that are present in all samples. Among the anthocyanins, cyaniding derivatives were present in all vegetables. In terms of their antioxidant activities, the analyzed vegetables were ranked as red chicory > purple sweet potato > black carrot > eggplant > red onion, in descending order. Superior antioxidant activities exhibited by red chicory and purple sweet potato were attributed to the high content of phenolic compounds, especially flavonols (quercetin-3,4-O-diglucoside) in red chicory and anthocyanins (peonidin-3-caffeoyl p-hydroxybenzoylsophoroside-5-glucoside) in purple sweet potato.

Chemical composition, UV/vis absorptivity, and antioxidant activity of essential oils from bark and leaf of phoebe zhennan S. K. Lee & F. N. Wei

The chemical composition of essential oils (EO) from bark and leaf of P. zhennan was identified by GC-MS. The compounds of α-calacorene, τ-cadinol, β-eudesmol and d-cadinene were found in the essential oils from both bark and leaf. The UV-Vis spectra results indicated the EO could completely absorbed the UV light at the wavelength range of 200-370 nm, revealing that EO had great potential as additives for manufacturing UV light blocking products. The radical DPPH scavenging activity assay showed that both the bark and leaf EO possessed strong DPPH radical scavenging activity of 90.25% and 82.10% respectively, which provides an important theoretical guiding in exploiting the value of P. zhennan bark and leaf.

Antioxidant and Antidiabetic Potential of Galing Stem Extract (Cayratia trifolia Domin)

Galing (Cayratia trifolia Domin.) have been used empirically to treat various diseases, one of them is antidiabetic. Objective: To determine the phytochemical content and the activity of the ethanol extract of the galing stem as antioxidant and antidiabetic. Method: The galing stem extract was investigated for phytochemical by Thin Layer Chromatography (TLC) and its antioxidant activity using DPPH scavenging activity assay. In vivo, antidiabetic test was conducted by animal diabetes modeling that has given streptozotocin 150 g/kg BW and 10% of sucrose solution intraperitoneally. The average level of fasting blood glucose at 307 mg/dL. Mice were divided into 6 groups, normal control group, diabetes induction group, positive group (treated by glibenclamide) and treatment group consisted of three groups were treated by ethanol extract of galing stem in dose 400, 500, and 600 mg/kg BW, respectively. Mice treated with appropriate doses of each treatment once a day for 7 days. The measuring blood glucose level was using a photometer 5010V5+. Results: The ethanol extract of galing stem contained the alkaloid, flavonoid, saponin, tannin, and triterpene. It is potential as an antioxidant with the IC50 61,52 mg/L which indicated that the extract had strong antioxidant. The antidiabetic activity showed that the effect of extract 400 and 500 mg/kg BW are not different significantly with glibenclamide in reducing blood glucose levels subset of the statistics ANOVA (p> 0.05). Conclusion: The ethanol extract of galing steam is potent as an antioxidant due to the phytochemical content inside particularly the flavonoid compound.

Antioxidant Activities of the Methanol Extracts of Various Parts of Phalaenopsis Orchids with White, Yellow, and Purple Flowers

Phalaenopsis (Phal.) orchids including white, yellow, and purple flowers are some of the most important commercial orchids worldwide. These flowering plants can be considered to be promising sources of antioxidants since several medicinal orchids were shown to have potential antioxidant activities. The antioxidant activities and several secondary metabolite compounds of the methanolic extracts of four parts (the root, pedicel, leaf, and flower) of three hybrids of white (Phal. ‘City More’), yellow (Phal. ‘Sogo Meili’), and purple (Phal. ‘Queen Beer’) flowering orchids were investigated. Results showed that the highest levels of chlorophyll a and chlorophyll b were respectively obtained in leaf extracts of white and purple orchids, whereas carotenoid showed the highest content in the flower extract of the yellow orchid. Among all tested extracts, flavonoids and anthocyanin demonstrated the highest levels in the flower extract of the purple orchid, whereas the highest level of polyphenols was observed in the flower extract of the yellow orchid. The leaf extract of the white orchid was the most effective extract with a 50% inhibitory concentration in the DPPH-scavenging activity assay, while the highest ferrous iron-chelating effect was observed in flower extracts of the yellow orchid and purple orchid, and the pedicel extract of the purple orchid. In the reducing power assay, the flower extract of the white orchid showed the most potent extract, followed by the leaf extract of the yellow orchid and the flower extract of the purple orchid. Relationships between flower colors and antioxidant activities of these orchids showed them to be potential sources of antioxidants for both medicinal use and stress-tolerance in these orchids.

Antioxidant activity of Juniperus communis L. essential oil in cooked pork sausages

The antioxidant and antimicrobial activity of Juniperus communis L. essential oil (JO) in cooked sausages was examined. Sausages with different concentrations of JO (0.15.0 µl/g) and a control were prepared. Instrumental parameters of colour (CIE L*a*b*), TBARS values, DPPH scavenging activity assay, microbial profile, and sensory panel scores have been assessed. Batches produced with the JO addition were darker and redder compared to the control. Sausages with the addition of 1.0, 2.0 and 5.0 µl/g JO showed the significantly (P &amp;lt; 0.05) lower TBARS values compared to the control. The addition of JO decreased radical formation and reduced the growth of total aerobic mesophilic bacteria. The flavour of sausages produced with the addition of 0.1 and 0.5 µl/g JO was slightly/moderately and significantly (P &amp;lt; 0.05) different from the control. This study demonstrates the significant antioxidant and antimicrobial activity of Juniperus communis L. essential oil, as well as the potential of its utilisation in the production of cooked pork sausages to enhance quality.

How do grinding and sieving impact on physicochemical properties, polyphenol content, and antioxidant activity of Hieracium pilosella L. powders?

In this work, phytochemical properties of Hieracium pilosella L. powders of different particle sizes were assessed. Four granulometric classes with 180, 315, and 500µm sieves, as well as the unsieved plant powder were studied for that purpose. Antioxidant activity was determined by DPPH scavenging activity assay and the main bioactive compounds found in H. pilosella L. were quantified by LC-PDA-ESI/MS. The highest antioxidant activity was obtained for the 180–315µm and 315–500µm fractions, with 22.5 and 22.3mg Trolox equivalents per gram of dried matter, respectively. The major bioactive compounds of H. pilosella L., including phenolic acids, flavonoids, and umbelliferone, were evidenced in hydromethanolic extracts. Their maximum content was reached for the same granulometric classes as for maximal antioxidant activity. These results highlighted the interest of grinding and sieving for improving phytochemical properties such as antioxidant activity and bioactive compound content of plants.

Antioxidant activities and oxidative stress inhibitory effects of ethanol extracts from Cornus officinalis on raw 264.7 cells.

BackgroundCornus officinalis, is a deciduous tree native to the eastern Asia, distributes mainly in (e.g. Korea, as well as China, and Japan). It is used as folk medicine to backache, polyuria, hypertension and nervous breakdown. Pharmacological studies have demonstrated that C. officinalis possess anti-oxidant, anti-hyperglycemic, and immune regulatory effects. However, reports on the antioxidant activity of C. officinalis have been limited to in vitro radical scavenging studies. Its mechanism of action within the cell at the genetic level especially has not yet been clearly defined. Therefore, we investigated the anti-antioxidant activities of C. officinalis in RAW 264.7 cells.MethodsThe antioxidant activities and protective effects of C. officinalis ethanol extract on cell damage and the antioxidant enzyme system in lipopolysaccharide (LPS)-induced oxidative stress-damaged RAW 264.7 cells were assessed. To measure the effects of C. officinalis on antioxidant activities, we used the following methods: Total phenol and flavonoid contents, DPPH scavenging activity assay, ABTS scavenging activity assay, FRAP value measurement, xanthine oxidase activity assay, ROS generation measurement and real time PCR.ResultsThe total phenol and flavonoid contents of C. officinalis extracts were 27.04 mg GAE/g and 3.70 mg QE/g, respectively. The antioxidant activities of C. officinalis extracts increased in a dose-dependent manner: the IC50 values for DPPH and ABTS radical scavenging activities of C. officinalis extracts were 99.32 μg/mL and 138.51 μg/mL, respectively. C. officinalis extracts inhibited xanthine oxidase activity and reactive oxygen species generation. The expression of antioxidant enzymes, Cu/ZnSOD, MnSOD, catalase, and glutathione peroxidase increased upon treatment with C. officinalis extracts at 100 μg/mL, compared to that in the LPS-treated group.ConclusionsThese results suggest the therapeutic potential of C. officinalis extract as an anti-oxidant agent.Electronic supplementary materialThe online version of this article (doi:10.1186/s12906-016-1172-3) contains supplementary material, which is available to authorized users.

Antioxidant and structure–activity relationships (SARs) of some phenolic and anilines compounds

The scavenging behavior of a series of phenolic and anilines compounds toward H2O2 and DPPH was examined. The efficient concentration (EC50) was calculated for all compounds under investigation by using H2O2-scavenging activity assay. The antiradical efficiency (AE) and EC50 were calculated for all investigated compounds by applying DPPH scavenging activity assay. Wide differences among compounds in each series and between the two series were observed. In H2O2-scavenging activity assay, the anilines series were more active than the phenolic series due to the reduction properties of the anilines compounds. While in the DPPH scavenging activity, the phenolic compounds were more active than the anilines compounds due to the lower bond dissociation energies (BDE) of O–H than that of N–H. So, the phenolic compounds were comparatively easier to lose H atom than anilines. The antioxidant activity related to the compound structure was found to be dependable on the number of the included active group (OH or NH2). The more active compound is the more included active groups. The position of the active groups also plays an important role of structure–antioxidant relationship activity. The ortho position was found to be the more active one, due to its ability to form intramolecular hydrogen bonding (iHB), followed by para position and then meta position of compounds.

Free radical-scavenging capacity, antioxidant activity, and phenolic composition of green lentil ( Lens culinaris)

Phenolics were extracted from green lentil seeds with 80% (v/v) aqueous acetone, and the resultant extracts were further separated on a Sephadex® LH-20 column. Fraction I, comprising low-molecular-weight phenolics, was eluted from the column with 95% (v/v) ethanol. Fraction II, consisting predominantly of tannins, was obtained using acetone:water (1:1; v/v) as the mobile phase. Phenolic compounds present in the preparations showed antioxidant and radical-scavenging properties as revealed by a β-carotene-linoleate model system, the total antioxidant activity (TAA) method, the DPPH scavenging activity assay, and a reducing power assay. Data from these tests showed the greatest efficacies coming from the tannins ( i.e., fraction II); the mean TAA of the tannin fraction was 6.09 μmol Trolox eq./mg fraction (d.w.), whereas the crude extract and fraction I showed 0.75 and 0.33 μmol Trolox eq./mg extract or fraction (d.w.), respectively. The content of total phenolics in fraction II was the highest (338 mg catechin eq./g fraction, d.w.), and the tannin content, as determined by the vanillin/HCl method and expressed as absorbance units at 500 nm per 1 g, was 252. Twenty compounds (hydroxycinnamates, procyanidins, gallates, flavonols, dihydroflavonols, dihydrochalcones) were identified in the crude extracts by HPLC-PAD and HPLC–ESI-MS techniques. Catechin and epicatechin glucosides, procyanidin dimers, quercetin diglycoside, and trans- p-coumaric acid were the dominant phenolics in green lentils.