Antidiabetic and antioxidant potency evaluation of different fractions obtained from Cucumis prophetarum fruit

Abstract

Context: Cucumis prophetarum Linn. (Cucurbitaceae) fruit is used for inflammatory-related problems and is proved to be possessing anticancer and hepatoprotective effects.

Objective: The present investigation was to study the effect of different fractions of C. prophetarum on antidiabetic and antioxidant activity.

Materials and methods: Aqueous crude extract (CE) of C. prophetarum fruits was fractionated into water soluble fraction 1 (F1), chloroform fraction 2 (F2), basic fraction 3 (F3), and neutral fraction 4 (F4) by acid–base extraction. CE and its fractions at different doses (0.02–0.1?mg/mL) were subjected to antidiabetic (α-amylase and α-glucosidase inhibition assays) and antioxidant (DPPH, superoxide radical scavenging (SO) and metal chelation) evaluation.

Results: F1 exhibited effective antidiabetic activity (p?<?0.05) with an IC₅₀ value of 20.6 and 59.9?µg/mL. The activity decreased in the order of CE?>?F4?>F3?>?F2, according to α-amylase assay, which were the same, with the exception of the rank order of F4 and CE, as the α-glucosidase assay. Furthermore, F1 (IC₅₀?=?73?µg/mL) showed better reducing ability than CE?>F4?>F2?>?F3 (IC₅₀?=?78–272?µg/mL), according to the DPPH assay. In SO and metal chelation assays, F1 showed the highest activity (IC₅₀?=?101 and 147?µg/mL), respectively; the activity decreased in the order of CE?>F4?>F3?>?F2 (IC₅₀?=?126–469?µg/mL) for SO and 194–944?µg/mL for metal chelation assay.

Conclusion: The results indicate that F1 possesses potent in vitro antidiabetic and antioxidant activities.     

Coffee silverskin: A possible valuable cosmetic ingredient

Abstract

Context: Currently, there is a great tendency in cosmetic area to use natural extracts. Coffee silverskin (CS) is the most abundant solid by-product generated during roasting of coffee processing.

Objectives: To evaluate different CS extracts as promising cosmetic ingredients, regarding antioxidant, antimicrobial, and cytotoxic properties.

Materials and methods: Aqueous, hydroalcoholic and ethanolic CS extracts were obtained by an environmentally friendly procedure considering costs and pollution. Extracts were characterized for total phenolic and flavonoid contents (TPC and TFC, respectively), antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), antimicrobial activity expressed as minimal inhibitory concentration (MIC) and cytotoxicity using the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) and lactate dehydrogenase (LDH) assays in two skin cell lines (fibroblasts and keratinocytes).

Results: The TPC of extracts was 18.33–35.25?mg of gallic acid equivalents per g of material on a dry basis (mg GAE/g?db). The TFC of extracts was 1.08–2.47?µg cathechin equivalents per g dry material (µg CE/g db). The antioxidant activity was high, with values ranging between 95.95 and 216.40?µmol Fe²⁺/g for aqueous and alcoholic samples, respectively. Preliminary assays for antimicrobial potential showed that extracts display antibacterial activity. The MIC varied from 31.3 to 250?µg/mL for Gram-positive, and from 31.3 to 1000?µg/mL for Gram-negative. Extracts did not affect in vitro cell viability, with values near 100% in all concentrations tested.

Conclusion: Results seem show that CS is a safe source of natural antioxidants with antifungal and antibacterial activity and no cytotoxicity, with potential usefulness for cosmetic applications.     

Seasonal,gender and regional variations in total phenolic,flavonoid, and condensed tannins contents and in antioxidant properties from Pistacia atlantica ssp. leaves

Context: The widespread use of Pistacia atlantica Desf. ssp. (Anacardiaceae) in traditional medicine can be partly attributed to the content of its secondary metabolites, in particular, the phenolic compounds.

Objective: The effects of harvest period, growing region and gender on the phenolic compounds, flavonoids and condensed tannins contents were studied, as well as on the antioxidant activities of P. atlantica leaves in order to provide a scientific basis for optimal collection.

Materials and methods: Leaves were collected monthly from April to October 2010 in two Algerian sites. The powdered leaves were used for preparing the ethyl acetate extract. Contents of total phenolics (TPC), flavonoids (FC) and condensed tannins (CTC) were determined spectrophotometrically. Antioxidant activity was evaluated through radical scavenging activity (RSA) of 2,2-diphenyl-1-picrylhydrazyl (250?μM) and the reducing power capacity (RPC) determination by K₃Fe(CN)₆ (1%).

Results: The TPC was found to vary from 79?±?13 to 259?±?8?mg gallic acid equivalents/g of dry weight (DW) during the study period. The RSA and RPC varied between 262?±?18 and 675?±?21?mg Ascorbic Acid Equivalent (AAE)/g DW, and from 259?±?16 to 983?±?20?mg AAE/g DW, respectively. A seasonal pattern was observed consisting of a decrease in TPC content and RPC from spring to autumn. The FC, CTC and RSA did not show a seasonal pattern.

Discussion and conclusion: Our findings showed that secondary metabolite content and antioxidant activities of P. atlantica leaves were more influenced by harvest time and growing region than by gender.     

Chemical composition,antioxidant, antitumor,anticancer and cytotoxic effects of Psidium guajava leaf extracts

Context Psidium guajava L. (Myrtaceae) leaves are used in traditional medicines for the treatment of cancer, inflammation and other ailments.

Objective The current study explores scientific validation for this traditional medication.

Materials and methods We used ferric-reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picryl hydrazil (DPPH) assays to estimate antioxidant activity of P. guajava leaf extracts (methanol, hexane and chloroform). Antitumour and in vivo cytotoxic activities were determined using potato disc assay (PDA) and brine shrimp lethality assay, respectively. Three human carcinoma cell lines (KBM5, SCC4 and U266) were incubated with different doses (10–100?μg/mL) of extracts and the anticancer activity was estimated by MTT assay. NF-κB suppressing activity was determined using electrophoretic mobility shift assay (EMSA). Chemical composition of the three extracts was identified by GC-MS. Total phenolic and flavonoid contents were measured by colorimetric assays.

Results and discussions The order of antioxidant activity of three extracts was methanol?>?chloroform?>?hexane. The IC₅₀ values ranged from 22.73 to 51.65?μg/mL for KBM5; 22.82 to 70.25?μg/mL for SCC4 and 20.97 to 89.55?μg/mL for U266 cells. The hexane extract exhibited potent antitumour (IC_50? value?=_?65.02?μg/mL) and cytotoxic (LC_50? value?=_?32.18?μg/mL) activities. This extract also completely inhibited the TNF-α induced NF-κB activation in KBM5 cells. GC-MS results showed that pyrogallol, palmitic acid and vitamin E were the major components of methanol, chloroform and hexane extracts. We observed significant (p?<?0.05) difference in total phenolic and flavonoid contents of different solvent extracts.

Conclusion The present study demonstrates that P. guajava leaf extracts play a substantial role against cancer and down-modulate inflammatory nuclear factor kB.     

In vitro antioxidant activity of Bombax malabaricum flower extracts

Context: Bombax malabaricum DC. (Bombacaceae) is a traditional Chinese herbal medicine used for the treatment of inflammatory conditions, diarrhea, fever, chronic inflammation, catarrhal affection, and as a diuretic. However, little information is available about its antioxidative activity.

Objective: Water, 50% ethanol, and 80% acetone extracts from flowers of B. malabaricum were investigated for their in vitro antioxidant activity in this article for the first time. Then the relationships between antioxidant activity measured by different methods and total phenolic content (TPC) and total flavonoid content (TFC) were established.

Materials and methods: The antioxidant activities of extracts from B. malabaricum flower were investigated including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity, oxygen radical absorbance capacity (ORAC), reducing power, and inhibition on phosphatidylcholine liposome peroxidation.

Results: Results showed that all the extracts possessed remarkable antioxidant capacity compared with ascorbic or gallic acids. Total antioxidant activities evaluated by ORAC assay of different extracts ranged from 700.03 to 1482.46 μmol Trolox equivalents/g. The highest TPC of 130.38?mg gallic acid equivalents (GAE)/g was observed in 80% acetone extract, whereas the lowest TPC of 57.09?mg GAE/g was obtained in the water extract. Furthermore, TFC exhibited significant (P?<?0.05) positive correlations with DPPH radical-scavenging activity, ORAC, and reducing power.

Discussion and conclusion: These findings demonstrate that the flowers of B. malabaricum have excellent antioxidant activities and thus might be a potential source of natural antioxidants.     

Antioxidant,anti-collagenase and anti-elastase activities of Phyllanthus emblica,Manilkara zapota and silymarin: an in vitro comparative study for anti-aging applications

Context Phyllanthus emblica L. (Euphorbiaceae) (amla), Manilkara zapota L.P. Royen (Sapotaceae) (sapota) and silymarin are reported to contain antioxidant effects. However, information on other biological activities relating to the anti-aging properties is limited.

Objective To compare in vitro antioxidants, anti-collagenase (MMP-1 and MMP-2) and anti-elastase properties as well as the phenolic and flavonoid contents of amla, sapota and silymarin as potential anti-aging ingredients.

Materials and methods The ethanol amla and sapota fruit extracts were prepared by three cycles of maceration with 24 h duration each. The total phenolic (TPC) and flavonoid (TFC) contents were determined. The antioxidant capacity was evaluated by DPPH and ABTS assays. The effects of MMP-1, MMP-2 and elastase inhibitions were determined by using the EnzChek® assay kits (Molecular-Probes, Eugene, OR).

Results Amla exhibited the highest in TPC (362.43?±?11.2?mg GAE/g) while silymarin showed the highest in TFC (21.04?±?0.67?mg QE/g). Results of antioxidant activity by DPPH and ABTS methods showed that amla possessed the most potent capacity with IC₅₀ values of 1.70?±?0.07 and 4.45?±?0.10?μg/mL, respectively. Highest inhibitions against MMP-1, MMP-2 and elastase were detected for sapota with IC₅₀ values of 89.61?±?0.96, 86.47?±?3.04 and 35.73?±?0.61?μg/mL, respectively.

Discussion and conclusion Test extracts offered anti-aging properties in different mechanisms. Amla showed the highest phenolic content and antioxidant property with moderate anti-collagenase. Silymarin exhibited measurable flavonoid content with anti-elastase effect. Sapota showed the highest collagenase and elastase inhibitions with moderate antioxidant effect. Thus, extracts might be added as a mixture to gain the overall anti-aging effects.     

Protective effects of Scutellaria lindbergii root extract against oxidative-induced cell and DNA damage in mouse fibroblast-like cells

Context: Scutellaria lindbergii Rech. f. (Lamiaceae) is an Iranian species of Scutellaria which has been shown to exert antimicrobial, antioxidant and cytotoxic effects. Objective: The protective properties of total methanol extract (TME) of S. lindbergii and its fractions (defatted and CH₂Cl₂) were investigated against cytotoxic and genotoxic effects of H₂O₂ in NIH 3T3 cell line as non-malignant cells. Materials and methods: The cells were incubated with different concentrations of S. lindbergii root extracts [TME (15–250?μg ml^?1), defatted fraction (15–500?μg ml^?1) and CH₂Cl₂ fraction (5–40?μg ml^?1)] and toxic concentration of H₂O₂ (200?µM) at 37?°C for 2?h concurrently and Cell viability was quantitated by MTT assay. The antigenotoxic effect of extracts was investigated using comet assay. The cells were incubated with extracts [TME (25–250?μg ml^?1), defatted fraction (25–500?μg ml^?1) and CH₂Cl₂ fraction (5–40?μg ml^?1)] and H₂O₂ (25?µM) at 4?°C for 20?min, then the comet assay was performed. DNA damage was expressed as percentage tail DNA. Results: Total methanol extract of S. lindbergii and its fractions had a significant inhibitory effect on DNA damage. The IC₅₀ values of TME, defatted fraction and CH₂Cl₂ fraction against DNA damage were determined as 48, 138 and 8?μg ml^?1, respectively. Conclusion: S. lindbergii extracts can prevent oxidative DNA damage, which is likely due to its flavonoids and phenolic compounds as antioxidant constituents.     

HPTLC analysis,antioxidant, anti-inflammatory and antiproliferative activities of Arisaema tortuosum tuber extract

Context: Oxidative stress and inflammation are related to several chronic diseases including cancer and atherosclerosis. Arisaema tortuosum (Wall.) Schott (Araceae) is an Indian folk medicinal herb traditionally used for treatment of various diseases related to inflammation and stress.

Objective: This study was carried out for HPTLC analysis and evaluation of antioxidant, anti-inflammatory and antiproliferative activities of a methanol extract of A. tortuosum tuber.

Materials and methods: The antioxidant activities of methanol extract of A. tortuosum tuber (1?mg/mL) were evaluated by DPPH, ABTS and FRAP assays and anti-inflammatory effects by diene-conjugate and β-glucuronidase assays, with in vitro tumor growth inhibition on HeLa cancer cells. The results for antioxidant and anti-inflammatory effects were compared using Trolox and salicylic acid as reference compounds, respectively.

Results: The TLC and HPTLC analysis showed the presence of quercetin, rutin, luteolin and lectin (R_f values 0.97, 0.53, 0.59 and 1.58, respectively). The methanol fraction of tuber exhibit higher activity in each antioxidant system with a special attention for DPPH (IC₅₀?=?852?μg/mL), ABTS (IC₅₀?=?532?μg/mL), and FRAP (IC₅₀?=?458?μg/mL), as compared with Trolox as standard, with a remarkable amount of phenolics (86.2?mg/100?g) and flavonoids (175.5?mg/100?g), along with potent anti-inflammatory activity indicated by diene-conjugate (86.20%) and β-glucuronidase (92.92%) inhibition, as compared with salicylic acid as reference compound. The antiproliferative activity at 100?mg/mL was 88% inhibition with HeLa cells. The inhibition of HeLa cell proliferation was greatest (p?A. tortuosum tuber extract treatments and least with the 25?mg/mL dose.

Discussion and conclusion: Our results suggested that A. tortuosum tuber might be used as a promising and potent antioxidant, anti-inflammatory, and antiproliferative agent and might be used for standardization of potential drug after successful isolation and characterization of bioactive compounds.     

Antioxidant activity of phenolic extracts from different cultivars of Italian onion (Allium cepa) and relative human immune cell proliferative induction

Context: The total antioxidant activity (TAC) may vary considerably between onion cultivars. Immunological effects of onion phenolic compounds are still underestimated.

Objective: The objective of this study is to determine the total phenol content (TPC) and the relative TAC of three Allium cepa L. (Liliaceae) onion cultivars cultivated in Cannara (Italy): Rossa di Toscana, Borettana di Rovato, and Dorata di Parma, and to evaluate the phenol extracts ability to induce human immune cell proliferation.

Materials and methods: TPC was determined by the Folin–Ciocalteu method, TAC with FRAP, TEAC/ABTS, and DPPH methods. Peripheral blood mononuclear cells from healthy human donors were incubated for 24?h at 37?°C with 1?ng/mL of phenolic extract in PBS, immunostained, and then analyzed by 4-color flow cytometry for the phenotypic characterization of T helper cells (CD4+ cells), cytotoxic T lymphocytes (CD8+ cells), T regulatory cells (CD25high CD4+ cells), and natural killer cells/monocytes (CD16+ cells).

Results: Rossa di Toscana displayed the highest TPC (6.61?±?0.87?mg GA equivalents/g onion bulb DW) and the highest TAC with the experienced methods: FRAP, 9.19?±?2.54 μmol Trolox equivalents/g onion bulb DW; TEAC/ABTS, 21.31?±?0.41 μmol Trolox equivalents/g onion bulb DW; DPPH, 22.90?±?0.01 μmol Trolox equivalents/g onion bulb DW. Incubation with Rossa di Toscana extract determined an increase in the frequency of the antitumor/anti-infection NK CD16+ immune cells (23.0?±?0.4%).

Discussion and conclusions: Content of health-promoting phenols and the deriving antioxidant and immunostimulating activity vary considerably among the investigated cultivars. Rossa di Toscana can be considered as a potential functional food.     

Antioxidant,antimicrobial and wound healing properties of Struthanthus vulgaris

Context: Struthanthus vulgaris (Vell.) Mart. (Loranthaceae) has been widely used in traditional medicine in Brazil to bathe wounds.

Objective: The objective of this study is to investigate the in vitro wound healing effects, together with the antioxidant and antimicrobial activities of S. vulgaris leaf and branch extracts.

Material and methods: Ethanol leaf and branch extracts of S. vulgaris were investigated at 1–100?µg/ml concentrations in the scratch assay after 14?h. Antioxidant activity was investigated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assay, and the antibacterial activity was tested at concentrations up to 1000?µg/ml against Gram-positive and Gram-negative bacteria by the microdilution test after 24?h. The total phenolic and flavonoid contents were determined by colorimetric methods.

Results: Struthanthus vulgaris leaf and branch extracts at 100?µg/ml concentration stimulated migration and proliferation of fibroblasts and enhanced cell numbers by 56.2% and 18.6%, respectively. Antioxidant activity exhibited IC₅₀ values of 24.3 and 18.9?µg/ml for the leaf and branch extracts, respectively. The ethanol leaf extract showed antimicrobial activity against the Gram-positive Staphylococcus mutans and Staphylococcus aureus bacteria, exhibiting minimum inhibitory concentration values of 125 and 500?µg/ml, respectively. An appreciable total phenolic content in the leaves (813.6?±?2.7?mg/g) and branches (462.8?±?9.6?mg/g), and relatively low concentration of flavonoids in the leaves (13.3?±?4.3?mg/g) and branches (1.9?±?0.2?mg/g), was detected.

Discussion and conclusion: The antioxidant and antibacterial activities, together with the strong ability to stimulate proliferation and migration of fibroblasts, provide some support for the traditional use of S. vulgaris.     

Antioxidant activity and total phenolic content of methanol extracts of Ixora coccinea

Objective: To investigate the in vitro antioxidant activity of methanol extracts of Ixora coccinea L. (Rubiaceae) flower, leaf and stem.

Materials and methods: The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, total antioxidant capacity (TAC) and xanthine oxidase inhibition assay were carried out to evaluate the antioxidant potential of the extract. The IC₅₀ values were calculated for the DPPH and xanthine oxidase assays in order to evaluate the antioxidant efficiency of each of the I. coccinea extracts. The phenol contents were also determined.

Results: I. coccinea flowers revealed the best antioxidant property, presenting much lower IC₅₀ value (6.6?mg/mL for DPPH assay). The flower extract showed a significantly higher antioxidant capacity compared to the other extracts. Furthermore, the highest phenolic content (polyphenols) was found in the flower extract (210.55?±?6.31 µg GAE/mg extract). Moreover, I. coccinea extracts scavenged the superoxide radical generated by the xanthine/xanthine oxidase system. The xanthine oxidase inhibition activity was in the order of allopurinol > leaf > flower > stem with the percentage of inhibition ranged from 39.7% to 77.3% for the plant parts investigated. The highest phenolic contents (polyphenols) were found in the flower extracts (210.55?±?6.31 µg GAE/mg extract).

Conclusions: I. coccinea could be considered as a potential source of natural antioxidant.     

Inter-species comparative antioxidant assay and HPTLC analysis of sakuranetin in the chloroform and ethanol extracts of aerial parts of Rhus retinorrhoea and Rhus tripartita

Context: Extensive research on Rhus (Anacardiaceae) shows their antioxidant potential, which warrants further evaluation of its other species.

Objective: To perform a comparative antioxidant assay on extracts of R. retinorrhoea and R. tripartita, including sakuranetin quantification by a validated HPTLC method.

Materials and methods: In vitro antioxidant assay was performed on chloroform and ethanol extracts of R. retinorrhoea Steud. ex Oliv. (RRCE and RREE) and R. tripartita (Ucria) Grande (RTCE and RTEE) by DPPH radical scavenging (at 31.25, 62.5, 125, 250 and 500?μg/mL concentrations) and β-carotene-linoleic acid bleaching methods at 500?μg/mL concentration. Densitometric HPTLC method was developed and validated using toluene: ethyl acetate: methanol (8:2:0.2; v/v/v) as mobile phase, executed on glass-backed silica gel F₂₅₄ plate and scanned at 292?nm.

Results: Antioxidant activity of Rhus extracts tested by the two methods (DPPH/BCB) was found in order of RTEE?>?RREE?>?RTCE?>?RRCE with IC₅₀ 118.67/256.26, 315.75/82.35, 827.92/380.0 and 443.69/292.75, respectively. Scanning of the HPTLC plate provided an intense peak of sakuranetin at R_f =?0.59. The estimated sakuranetin content in the dry weight of the extracts was highest in RREE (27.95?μg/mg) followed by RRCE (25.22?μg/mg), RTEE (0.487?μg/mg) and RTCE (0.0?μg/mg). Presence of sakuranetin in RREE, RRCE and RTEE supported the highest antioxidant property of the two Rhus species. Nonetheless, low sakuratenin in R. tripartita indicated the presence of other bioactive constituents responsible for synergistic antioxidant activity.

Conclusion: The developed HPTLC method therefore guarantees its application in quality control of commercialized herbal drugs and formulations containing sakuranetin.     

Chemical composition and biological investigation of Pelargonium endlicherianum root extracts

Context: Pelargonium endlicherianum Fenzl. (Geraniaceae) roots and flowers are traditionally used in Turkey as a decoction treatment against intestinal parasites. Neither the chemical composition nor the potential bioactivity of the plant roots has been studied before.

Objectives: The phenolic content and effects of P. endlicherianum root extracts on antioxidant enzyme levels on A549 cells were studied for the first time.

Materials and methods: The chemical composition was analyzed via spectrophotometric and chromatographic (HPLC MS/MS and HPLC) techniques. The antioxidant activity was determined at different concentrations ranging from 0.001 to 2?mg/mL using DPPH^? and ABTS^?+ radical scavenging activity, β-carotene-linoleic acid co-oxidation assay, protection of 2-deoxyribose and bovine brain-derived phospholipids against a hydroxyl radical-mediated degradation assay. Glutathione peroxidase and superoxide dismutase activities were also studied as well as the effects of the extracts on nitric oxide levels on IL-1β stimulated A549 cells.

Results: The key parameters for the most active ethyl acetate extract included the following: DPPH^? IC₅₀: 0.23?mg/mL, TEAC/ABTS: 2.17?mmol/L Trolox, reduction: 0.41?mmol/g AsscE, and protection of lipid peroxidation IC₅₀: 0.05?mg/mL. Furthermore, the ethyl acetate extract increased the SOD level significantly compared to control group (4.48?U/mL) at concentrations of 100 and 200?μg/mL SOD, 5.50 and 5.67?U/mL, respectively. Apocynin was identified as the major component, and the ethyl acetate fraction was found to be rich in phenolic compounds.

Discussion and conclusion: Pelargonium endlicherianum root extracts displayed antioxidant activity and increased the antioxidant enzyme levels in IL-1β stimulated A549 cells, while decreasing the NO levels.     

Free radical scavenging actions of three Trifolium species in the protection of blood plasma antioxidant capacity in vitro

Abstract

Context: Three clover [Trifolium L. (Leguminosae)] species were selected on the basis of data from traditional medicine, phytochemical profiles, and agricultural significance.

Objective: The in vitro evaluations of free radical scavenging properties, ferric reducing abilities, and antioxidant effects of extracts from T. pratense L. (crude extract and phenolic fraction), T. pallidum L., and T. scabrum L. (phenolic fractions) were performed.

Materials and methods: Activities of the Trifolium extracts were determined at their final concentrations of 1.5–50?µg/ml. Free radical scavenging properties of methanol extract solutions were estimated by the reduction of DPPH^? and ABTS^? radicals. Measurements of the total antioxidant capacity (TAC) were carried out to assess the antioxidant activities of the extracts in human blood plasma under conditions of oxidative stress, induced by 200?μM peroxynitrite.

Results: The phenolic fraction of T. pratense displayed the strongest ABTS^? and DPPH^? radical scavenging effects (EC₅₀ value of 21.69 and 12.27?µg/ml, respectively). The EC₅₀ value for T. pallidum extract attained 29.77 and 30.06?µg/ml. The two remaining extracts were less potent scavengers (EC₅₀ value higher than 50?µg/ml). Similar differences were obtained during evaluation of the ferric reducing abilities. Analysis of antioxidant properties of the extracts in blood plasma did not provide such evident differences in their actions, however, it indicated that the T. pratense phenolic fraction displayed the strongest effect.

Conclusions: The examined Trifolium extracts partly protected blood plasma and enhanced its non-enzymatic antioxidant defense against harmful action of peroxynitrite in vitro.     

Antioxidant activity and cytotoxicity of Cyrtosperma johnstonii extracts on drug sensitive and resistant leukemia and small cell lung carcinoma cells

Context: The number of patients with cancer is increasing. New therapeutic agents to overcome drug-resistant tumors are urgently needed. Cyrtosperma johnstonii N.E. Br. (Araceae) is used for treatment of cancer in Thai traditional medicine. This study aimed to evaluate antioxidant activity and cytotoxicity of C. johnstonii extracts on human cancer cells.

Materials and methods: Dried powder of C. johnstonii rhizomes was extracted with several solvents. The 0.1?mg/ml extract solution was tested for antioxidant activity by 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and ferric reducing antioxidant power (FRAP) assays. Color formation from 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide was used to determine cell viability. Standardization of the extract was performed by high-performance liquid chromatography (HPLC) with photodiode array detector at 254 and 360?nm. Cell cycle arrest was evaluated by flow cytometry after 5?min, 12?h and 24?h treated with 20 µg/ml of the acetone extract.

Results: The acetone extract exhibited the highest phenolic content and antioxidant activity (TEAC and EC values = 19.2?±?0.14 and 19.2?±?0.31?mM/mg, respectively). The IC₅₀ values for leukemia ranged from 11?±?1 to 29?±?3 µg/ml and from 5?±?2 to 6?±?0 µg/ml for small cell lung carcinoma cells. Cell cycle arrest occurred at the G2/M phase followed by apoptosis. HPLC analysis revealed that rutin is the major constituents of the extract.

Discussion and conclusion: The acetone extract of C. johnstoni is a promising source of natural antioxidants and anticancer. The extract inhibits cancer cells effectively with less effect on normal cells.     

Phytochemical screening and evaluation of in vitro antioxidant and antimicrobial activities of the indigenous medicinal plant Albizia odoratissima

Context: Albizia odoratissima (L. f.) Benth has been used in Indian folk medicine to treat numerous inflammatory pathologies, such as leprosy, ulcers, burns and asthma.

Objective: To evaluate the antioxidant and antimicrobial properties of A. odoratissima.

Materials and methods: Dried leaves of A. odoratissima were extracted in organic solvents (hexane, chloroform, ethyl acetate, and methanol). The total phenolic content (TPC) and total flavonoid content (TFC) were determined using the Folin-Ciocalteu and aluminum chloride colorimetric methods, respectively. The antioxidant activity was examined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydrogen peroxide (H₂O₂), 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS), and ferric reducing antioxidant power (FRAP) assays. The antibacterial activity was examined using minimum inhibitory concentration (MIC) and the minimum bacterial concentration (MBC), determined by broth microdilution method against Gram-negative bacteria (Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, and Proteus vulgaris) and Gram-positive bacterium (Staphylococcus aureus).

Results: The TPC ranged from 4.40?±?1.06 to 1166.66?±?31.85?mg GAE/g of dry weight (DW), and the TFC ranged from 48.35?±?3.62 to 109.74?±?1.84?mg QE/g of DW. The IC₅₀ values of the ethyl acetate extract for DPPH, ABTS, and H₂O₂ were 10.96?±?0.40, 4.35?±?0.07, and 163.82?±?1.52?μg/mL, respectively. Both methanol and ethyl acetate extracts demonstrated effective antibacterial activity with MICs and MBCs values ranging 136–546?μg/mL and 273–1093?μg/mL, respectively, against the tested pathogenic species.

Conclusions: The leaves of A. odoratissima showed potent free radical scavenging property and antimicrobial activity.     

Cytotoxic,antioxidant and antimicrobial effects of nine species of woundwort (Stachys) plants

Context: Woundwort (Stachys) plants from the Lamiaceae family have been used in folk medicine for various purposes.

Objective: This study was designed to analyze cytotoxic, antioxidant and antimicrobial activities of Stachys plants, because these fields have extensively benefited of drug discovery from natural sources.

Materials and methods: Nine Stachys plants were collected from different regions of Iran. Cytotoxic activities of methanol, 80% methanol and dichloromethane (DCM) extracts of these plants were assessed on three human cancer cell lines (HL-60, K562 and MCF-7 cells) with the MTT assay, while antioxidant and antimicrobial activities were determined on methanol extracts by DPPH and nutrient broth micro-dilution assays, respectively.

Results: DCM extract of St. pilifera Benth. had the lowest IC₅₀ in three cancer cell lines ranging from 33.1 to 48.2?µg/ml, followed by the 80% methanol extract of St. persica S.G.Gmel. ex C.A.Mey. (IC₅₀ range: 62.1–104.1?µg/ml) and DCM extract of St. byzantina C. Koch (IC₅₀ range: 62.7–131.0?µg/ml). St. byzantina. St. lavandulifolia Vahl., St. acerosa Boiss., St. obtusicrena Boiss. and St. persica showed lowest IC₅₀ values in the DPPH scavenging assay (135.1, 162.6, 164.7, 169.4 and 172.4?µg/ml, respectively), while their total phenolic contents were 23.9, 18.2, 18.6, 20.4, 27.8?mg equivalent of gallic acid in 1?g dry plant, respectively. The methanol extracts of St. byzantina and St. persica inhibited all six tested Gram-negative and Gram-positive bacterial strains.

Conclusion: Various Stachys species (especially St. byzantina and St. persica) are valuable sources of natural compounds with important biological properties.     

Anti-inflammatory and anti-proliferative activities of the wild edible cruciferous: Diplotaxis simplex

Context The present study deals with new biological properties of the wild edible Diplotaxis simplex (Viv.) Spreng (Brassicaceae).

Objectives The current study evaluates the antioxidant, the anti-inflammatory and the anti-cancer properties of ethyl acetate and ethanol extracts from D. simplex flowers.

Materials and methods The anti-proliferative activity of the extracts (10–70?μg/mL) was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) against human colon cancer cell line Caco-2. The anti-inflammatory potential was evaluated by the inhibitory effect of the extracts (1.5–7.5?mg/mL) on phospholipase A2 activity as well as on carrageenan-induced paw oedema in mice. Extracts (200?mg/kg) or indomethacin (50?mg/kg) as positive control were injected intraperitoneally for albino mice prior to the induction of the oedema by carrageenan. Antioxidant activities were investigated using various complementary methods.

Results Flower extracts contained a high level of polyphenolics (17.10–52.70?mg GAE/g) and flavonoids (74.20–100.60?mg QE/g), which correlate with its appreciable antioxidant potential in β-carotene peroxidation (IC₅₀ value: 12.50–27.10?μg/mL), DPPH^? radical-scavenging (IC₅₀ value: 0.20–0.40?mg/mL), Fe^3+?reducing (EC₅₀ value: 0.10–0.14?mg/mL) and Fe^2+?chelating (IC₅₀ value: 0.20–0.60?mg/mL) assays. These extracts were effective in inhibiting cancer cell growth (IC₅₀ value: 62.0–63.25?μg/mL). Besides, the ethyl acetate extract inhibited phospholipase A2 activity (IC₅₀ value: 2.97?mg/mL) and reduced the paw oedema in mice (from 0.38?±?0.01 to 0.24?±?0.01?cm), 4?h post-carrageenan challenge.

Conclusion These data suggest that D. simplex may be useful as a candidate in the treatment of inflammation and the colon cancer.     

Evaluation of in vitro antioxidant,anticancer and in vivo antitumour activity of Termitomyces clypeatus MTCC 5091

Context: Termitomyces clypeatus (Lyophyllaceae) is a filamentous edible mushroom, having ethnomedicinal uses. However, information about the antioxidant, anticancer and antitumour properties of this mushroom remains to be elucidated.

Objective: The study examines the in vitro antioxidant, anticancer and in vivo antitumour activity of T. clypeatus.

Materials and methods: Antioxidant activity was evaluated with seven in vitro assays. Cytotoxicity of T. clypeatus was tested against a panel of cancer cells lines including U373MG, MDA-MB-468, HepG2, HL-60, A549, U937, OAW-42 and Y-79 using MTT assay. The antitumour activity of aqueous extract was evaluated against Ehrlich ascites carcinoma (EAC) tumour model in Swiss albino mice.

Results: HPLC analysis of aqueous extract revealed the presence of sugar entities. Termitomyces clypeatus showed excellent in vitro antioxidant activity. Termitomyces clypeatus was found cytotoxic against all cancer cells, among which it showed higher activity against U937 (IC₅₀ 25?±?1.02?μg/mL). Treatment of EAC-bearing mice with varied doses of aqueous extract significantly (p?<?0.01) reduced tumour volume, viable tumour cell count and improved haemoglobin content, RBC count, mean survival time, tumour inhibition and % increase life span. The enhanced antioxidant status in treated animals was evident from the decline in the levels of lipid peroxidation, increased levels of glutathione, catalase and superoxide dismutase.

Discussion: The analyzed data indicate that the aqueous extract of T. clypeatus exhibits significant antitumour activity, which might be due to the antioxidant effects on EAC bearing hosts.

Conclusion: Termitomyces clypeatus possesses anticancer activity, valuable for application in food and drug products.