Antioxidant and antidiarrheal activities of ethanol extract of Ardisia elliptica fruits

Context: Ardisia elliptica Thunb Lam. (Myrsinaceae) is widely used traditionally in the treatment of diarrhea related health disorders in Bangladesh.

Objective: The crude ethanol extract of Ardisia elliptica fruits (EFA) was evaluated for its antioxidant and antidiarrhoeal activities.

Materials and methods: DPPH radical scavenging, nitric oxide scavenging, reducing power and Fe⁺⁺ ion chelating ability were used for determining antioxidant activities and animal models were used for antidiarrheal activities such as the castor oil and magnesium sulfate-induced diarrhea, enteropooling induced by the administration of castor oil and magnesium sulfate at the doses of 250 and 500?mg/kg.

Results: The extract possessed a significant DPPH free radical scavenging activity with an IC₅₀ value of 30.75?μg/ml compared to ascorbic acid (IC₅₀: 7.89?μg/ml). The IC₅₀ values of the extract and ascorbic acid were 51.72 and 38.68?μg/ml, respectively, in nitric oxide scavenging assay. The IC₅₀ value of the extract for Fe⁺⁺ ion chelating ability (41.30?μg/ml) was also found to be significant compared to the IC₅₀ value of EDTA (22.57?μg/ml). The EFA also showed a significant protection (p?Conclusion: Therefore, the obtained results confirm the antioxidant and antidiarrheal activity of EFA and thus support the traditional uses of this plant as a modality for antioxidant and antidiarrheal activity.     

Evaluation of the antidiarrheal and antioxidant properties of Justicia hypocrateriformis

Content: Justicia hypocrateriformis Vahl (Acanthaceae) is used as an herbal remedy for diarrhea in Cameroon folk medicine.

Objective: This study evaluates the antidiarrheal and antioxidant properties of the aqueous extract of J. hypocrateriformis (JH).

Materials and methods: Preliminary phytochemical screening and an acute toxicity testing of the extract were carried out. The antidiarrheal activity of JH extract (100, 250, and 500?mg/kg) was assessed at curative and preventive levels in castor oil-induced diarrhea in mice. The antioxidant activity was measured by ferric reducing antioxidant power (FRAP), total phenolic content, and radical scavenging activity.

Results: A high lethal dose (LD₅₀) of 14.35?g/kg obtained in acute toxicity implies the extract is not toxic. Phytochemical screening revealed the presence of phenols, tannins, flavonoids, saponins, anthraquinones, and anthocyanins. JH showed a significant protection against castor oil-induced diarrhea as evidenced by a decrease in the number of defecation and wet stool. JH (100–500?mg/kg, p.o.) produced a non-significant dose-dependent decrease in castor oil-induced intestinal transit in the preventive study. In the curative and in healthy mice study, the decrease was only significant at 500?mg/kg. JH possessed a radical scavenging activity with an IC₅₀ of 9.93?mg/ml compared to 4.90?mg/ml for catechin. JH FRAP of 2703.77?±?0?mg/g (catechin equiv) and phenolic concentration of 14?169.99?±?612.39?mg/g (catechin equiv) were also obtained.

Conclusion: Justicia hypocrateriformis extract possesses antidiarrheal activity supported by its antioxidant potential and phytochemical constituents.     

Anti-acetylcholinesterase activity and antioxidant properties of extracts and fractions of Carpolobia lutea

Context: There is an unmet need to discover new treatments for Alzheimer’s disease. This study determined the anti-acetylcholinesterase (AChE) activity, DPPH free radical scavenging and antioxidant properties of Carpolobia lutea G. Don (Polygalaceae).

Objective: The objective of this study is to quantify C. lutea anti-AChE, DPPH free radical scavenging, and antioxidant activities and cell cytotoxicity.

Materials and methods: Plant stem, leaves and roots were subjected to sequential solvent extractions, and screened for anti-AChE activity across a concentration range of 0.02–200?μg/mL. Plant DPPH radical scavenging activity, reducing power, and total phenolic and flavonoid contents were determined, and cytotoxicity evaluated using human hepatocytes.

Results: Carpolobia lutea exhibited concentration-dependent anti-AChE activity. The most potent inhibitory activity for the stem was the crude ethanol extract and hexane stem fraction oil (IC₅₀?=?140?μg/mL); for the leaves, the chloroform leaf fraction (IC₅₀?=?60?μg/mL); and for roots, the methanol, ethyl acetate and aqueous root fractions (IC₅₀?=?0.3–3?μg/mL). Dose-dependent free radical scavenging activity and reducing power were observed with increasing stem, leaf or root concentration. Total phenolic contents were the highest in the stem: ～632?mg gallic acid equivalents/g for a hexane stem fraction oil. Total flavonoid content was the highest in the leaves: ～297?mg quercetin equivalents/g for a chloroform leaf fraction. At 1?μg/mL, only the crude ethanol extract oil was significantly cytotoxic to hepatocytes.

Discussion and conclusions: Carpolobia lutea possesses anti-AChE activity and beneficial antioxidant capacity indicative of its potential development as a treatment of Alzheimer’s and other diseases characterized by a cholinergic deficit.     

Phytochemical analysis,antiproliferative and antioxidant activities of Chrozophora tinctoria: a natural dye plant

Context: Chrozophora tinctoria (L.) A. Juss. (Euphorbiaceae) is known as ‘dyer’s-croton’ and used to obtain dye substances. Recently, natural antioxidants and colorants have been of interest because of their safety and therapeutic effects.

Objective: This study investigates the antiproliferative and antioxidant activities of the various extracts and fractions from C. tinctoria and analyzes their phytochemical contents.

Materials and methods: The aerial parts of C. tinctoria were extracted with water, ethyl acetate, n-butanol, and methanol/chloroform. Phenolic compounds and other constituents of the extracts were analyzed by HPLC/TOF-MS. The ethyl acetate extract (EA) was fractionated by flash chromatography. The extracts, fractions, and major phenolic compounds were investigated for their antiproliferative activities on human cervical adenocarcinoma (HeLa) cell line at the concentrations of 5–100?μg/mL by using BrdU ELISA assay during 24?h of incubation. DPPH radical scavenging activities (5–150?μg/mL) and total phenolic contents of the samples were also evaluated.

Results: 4-Hydroxybenzoic acid (268.20?mg/kg), apigenin-7-glucoside (133.34?mg/kg), and gallic acid (68.92?mg/kg) were the major components of EA. CT/E-F6 (IC₅₀?=?64.59?±?0.01?μg/mL) exhibited the highest antiproliferative activity. CT/E-F2 (IC₅₀=?14.0?±?0.0?μg/mL) and some fractions displayed higher radical scavenging activity compared to synthetic antioxidant BHT (IC_50?=_?23.1?±?0.0?μg/mL). Among the main phenolics, gallic acid exhibited the highest antiproliferative and radical scavenging abilities (IC_50?<_?5?μg/mL).

Conclusion: In this study, we have determined the biologically active fractions and their high effects may be attributed to the presence of gallic acid.     

Phytochemical investigation and radical scavenging activities of Melia azedarach and its DNA protective effect in cultured lymphocytes

Abstract

Context: Melia azedarach Linn (Meliaceae) is an Ayurvedic medicinal plant which is native to India. It is traditionally used for the treatment of leprosy, inflammation, scrofula, anthelmintic, antilithic, diuretic, deobstruent and cardiac disorders.

Objective: To evaluate the phytochemical constituents and antioxidant activities of the ethanol leaf extract of Melia azedarach (MA) and its protective effect against H₂O₂-induced cellular damage in cultured lymphocytes.

Materials and methods: The dose-dependent study of MA (20, 40, 60, 80, 100?µg/ml) was used to study in vitro radical scavenging assays. The effective dose of MA (60?µg/ml) was further used to study the H₂O₂-induced DNA damage (comet assay and DNA fragmentation assay) in cultured lymphocytes.

Results: The ethanol extract of MA (20, 40, 60, 80, 100?µg/ml) exhibited a significant dose-dependent inhibition of in vitro radical scavenging assays and their corresponding IC₅₀ values as follows: hydroxyl radical (26.50?±?0.26?µg/ml), superoxide anion (30.00?±?0.32?µg/ml), nitric oxide radical (48.00?±?0.48?µg/ml), DPPH radical (30.55?±?0.32?µg/ml) and reducing power (22.00?±?0.22?µg/ml). The increase in the severity of DNA damage and TBARS was increased significantly (p?<?0.05) at 500?µM H₂O₂-treated cultured lymphocytes and RBC cellular membranes. The phytochemical screening studies identified 13 chemical constituents present in the leaf extract of MA.

Discussion and conclusion: The results of this study demonstrate that MA offers protection against H₂O₂-induced cellular damage and it can be developed as an effective antioxidant during oxidative stress.     

Potential anti-inflammatory,antioxidant and antimicrobial activities of Sambucus australis

Context: Sambucus australis Cham. &; Schltdl. (Adoxaceae) is used in Brazilian folk medicine to treat inflammatory disorders.

Objective: To evaluate the in vitro anti-inflammatory, antioxidant and antimicrobial properties of S. australis.

Materials and methods: The anti-in?ammatory activity of ethanol extracts of the leaf and bark of S. australis (1–100?μg/mL) were studied in lipopolysaccharide/interferon γ stimulated murine macrophages RAW 264.7 cells (24?h incubation) by investigating the release of nitric oxide (NO) and tumour necrosis factor-alpha (TNF-α) and in the TNF-α-induced nuclear factor kappa (NF-κB) assay. Minimum inhibitory concentration (MIC) was determined by the microdilution test (24?h incubation). Antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and the NO scavenging assays. Chemical composition was assessed by LC-MS/MS.

Results: Antioxidant activities in the DPPH (IC₅₀ 43.5 and 66.2?μg/mL), FRAP (IC₅₀ 312.6 and 568.3?μg/mL) and NO radical scavenging assays (IC₅₀ 285.0 and 972.6?μg/mL) were observed in the leaf and bark ethanol extracts, respectively. Solely the leaf extract showed significant inhibition of NO and TNF-α production in RAW264.7 cells at concentrations of 2 and 100?μg/mL, respectively, and suppression of TNF-α inhibition of NF-κB by 12.8 and 20.4% at concentrations of 50 and 100?μg/mL, respectively. The extract also exhibited antibacterial activity against Salmonella typhimurium (MIC 250?μg/mL) and Klebsiella pneumoniae (MIC 250?μg/mL). LC-MS/MS revealed the presence of chlorogenic acid and rutin as major compounds.

Discussion and conclusion: The results indicate that the ethanol leaf extract of S. australis exhibit prominent anti-in?ammatory effects.     

Chemical profile and biological activities of Veronica thymoides subsp. pseudocinerea

Abstract

Context: In Turkey, Veronica species (Plantaginaceae) have been used as a diuretic and for wound healing in traditional medicine.

Objective: To examine the fatty acid and essential oil profiles, the antioxidant, anticholinesterase, antimicrobial, and DNA damage effects of Veronica thymoides P.H. Davis subsp. pseudocinerea M.A. Fischer as a potential source of natural active compounds.

Materials and methods: GC/MS was used to analyze essential oil and fatty acid obtained from whole plant. The antioxidant activity was evaluated by the β-carotene-linoleic acid test system, DPPH-free and ABTS cation radicals scavenging, and cupric reducing antioxidant capacity assays. The anticholinesterase and antimicrobial activities were determined by Ellman and broth macrodillution methods, respectively. The effect of the methanol extract on DNA cleavage was investigated.

Results: Hexatriacontene (21.0%) was found to be the main constituent in essential oil, and linoleic acid (25.2%) and palmitic acid (20.6%) in fatty acid. Methanol extract demonstrated the best IC₅₀ values in lipid peroxidation (49.81?±?0.31?µg/ml) and DPPH-free radical scavenging activity (15.32?±?0.17?µg/ml). Methanol and water extracts possessed strong ABTS cation radical scavenging activity with IC₅₀ values 9.15?±?0.28 and 8.90?±?0.14?µg/ml, respectively. The acetone extract exhibited moderate butyrylcholinesterase inhibitory activity. The highest antimicrobial activity was determined in methanol extract against Escherichia coli with 31.25?µg/ml MIC value. Inhibition of methanol extract on plasmid DNA cleavage by OH radicals was found to be 93.32% at 500?µg/ml.

Conclusion: The methanol extract having strong antioxidant and DNA damage effects could be investigated phytochemically to find natural active compounds.     

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.     

In vitro antioxidant and anti-cholinesterase activities of Rhizophora mucronata

Context: Rhizophora mucronata Lam. (Rhizophoraceae), commonly known as Asiatic mangrove, has been used traditionally among Asian countries as folk medicine.

Objective: This study investigates the cholinesterase inhibitory potential and antioxidant activities of R. mucronata.

Materials and method: Rhizophora mucronata leaves were successively extracted using solvents of varying polarity and a dosage of 100–500?µg/ml were used for each assay. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities were assessed according to the method of Ellman. In vitro antioxidant activity was assessed using free radical scavenging, reducing power, and metal-chelating activity (duration – 3 months). Total phenolic and flavonoid content were quantified spectrophotometrically. Compound characterization was done using column chromatography, NMR, FTIR, and LC-MS analysis.

Results: Methanolic leaf extract (500?µg/ml) exhibited the highest inhibitory activity against AChE (92.73?±?0.54%) and BuChE (98.98?±?0.17%), with an IC₅₀ value of 59.31?±?0.35 and 51.72?±?0.33?µg/ml, respectively. Among the different solvent extracts, methanolic extract exhibited the highest antioxidant activity with an IC₅₀ value of 47.39?±?0.43, 401.45?±?18.52, 80.23?±?0.70, and 316.47?±?3.56?µg/ml for DPPH, hydroxyl, nitric oxide radical, and hydrogen peroxide, respectively. Total polyphenolic and flavonoid contents in methanolic extract were observed to be 598.13?±?1.85?µg of gallic acid equivalent and 48.85?±?0.70?μg of rutin equivalent/mg of extract. Compound characterization illustrated (+)-catechin as the bioactive compound responsible for cholinesterase inhibitory and antioxidant activities.

Conclusion: The presence of rich source of flavonoids, in particular catechin, might be responsible for its cholinesterase inhibitory and antioxidant activities.     

In vitro antioxidant and cytotoxic properties of ethanol extract of Alpinia oxyphylla fruits

Abstract

Context. Alpinia oxyphylla Miquel (Zingiberaceae) is a traditional Chinese herbal medicine widely used for the treatment of intestinal disorders, urosis and diuresis. However, information about antioxidant and cytotoxic properties of its fruits remains to be elucidated.

Objective: The ethanol crude extract (CE) and its fractions [petroleum ether fraction (PF), ethyl acetate fraction (EF), n-butanol fraction (BF) and water fraction (WF) extracted by petroleum ether, ethyl acetate, n-butanol and water, respectively] of A. oxyphylla fruits were investigated for their antioxidant activity and cytotoxicity.

Materials and methods: The total phenolic content (TPC) and antioxidant activity of the extracts were determined by Folin–Ciocalteu reagent, 1,1-diphenyl-2-picrylhydrazyl (DPPH^?), Trolox equivalent antioxidant capacity and reducing power assay. Cytotoxicity of the extracts (0–200?μg/mL) was tested on six human cancer cell lines (breast cancer cell line, cervix carcinoma cell line, lung adenocarcinoma cell line, liver carcinoma cell line, gastric cancer cell line and colon cancer cell line) using the sulforhodamine B assay.

Results: The TPC of extracts varied from 8.2 to 20.3?mg gallic acid equivalents/g dry weight. DPPH radical scavenging effect of extracts decreased in the order of EF?>?BF?>?CE?>?PF?>?WF, with IC₅₀ values ranging from 74.7 to 680.8?μg/mL. 2,2-azo-bis(3-Ethylbenzothiazoline-6-sulfoic acid) diammonium salt scavenging activity ranged from 0.118 to 0.236?mmol Trolox equivalence/mg extract. The extracts exhibited concentration-dependent reducing power, and EF showed the highest reducing ability. A satisfactory correlation (R²?>?0.826) between TPC and antioxidant activity was observed. In addition, EF, PF and CE exhibited potent anticancer effects on six cancer cell lines with IC₅₀ values ranging from 40.1 to 166.3?μg/mL.

Discussion and conclusion: The ethanol extract of A. oxyphylla fruit, especially the EF, was found to possess potent antioxidant and anticancer activities, and thus a great potential for the application in food and drug products.     

Bioactive potential of endophytic Myrothecium sp. isolate M1-CA-102, associated with Calophyllum apetalum

Context: Endophytes colonizing medicinal plants are diverse, constituting a rich bioresource for novel natural products.

Objective: Myrothecium sp. isolate M1-CA-102 was the most promising among the 16 Myrothecium isolates screened. The bioactive potential of the crude extract from the Calophyllum apetalum Willd. endophytic Myrothecium sp. (Alb. &; Schwein.) Ditmar (Incertae sedis) isolate M1-CA-102 and its thin layer chromatography (TLC) fractions were screened based on antioxidant, anti-inflammatory, antimicrobial activities, and cytotoxicity.

Materials and methods: The antioxidant activity was measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid (ABTS) radical scavenging capacities. Further, 15-lipoxygenase (15-LOX) and human cyclooxygenase-2 (COX-2) inhibition were assessed at different concentrations (25, 50, and 100?μg/mL for the crude extract, 5, 25, and 50?μg/mL for the TLC fractions). DNA-nicking assay as an indicator of the capacity of extracts to scavenge hydroxyl radical was recorded at a concentration of 50?μg/mL. Cell cytotoxicity was recorded by colorimetric 3-(4,5-dimethylthylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Antibacterial (Bacillus subtilis) and anti-Candida (Candida albicans) assays were performed by the microdilution method.

Results: The DPPH and ABTS IC₅₀ values of M1-CA-102 extract were 10 and 6?μg/mL compared with 6.1 and 7.03?μg/mL for the positive control quercetin. The cytotoxicity IC₅₀ value of M1-CA-102 extract was 37?μg/mL, while the M-I TLC fraction was 21?μg/mL. The M1-CA-102 extract gave an IC₅₀ value of 58 and 8?μg/mL for 15-LOX and COX-2, respectively. The MIC values for antimicrobial activity for M1-CA-102 extract ranged from 35 to 54?μg/mL, while for the TLC fractions, it ranged from 91 to 515?μg/mL.

Conclusion: The results indicate that Myrothecium M1-CA-102 isolated from C. apetalum is a potential source of natural metabolites of pharmaceutical importance.     

Free radical scavenging activity and chemical constituents of Urvillea ulmaceae

The methanol extract of Urvillea ulmaceae Kunth (Sapindaceae) aerial parts and the hexane, ethyl acetate, and hydromethanol fractions were evaluated for their free radical scavenging activity with the DPPH assay. Among all the tested fractions, the ethyl acetate fraction was the most active, exhibiting an IC₅₀ of 16.33?μg/mL, comparable to that of the commercial antioxidant BHT. Fractionation of the ethyl acetate fraction through chromatographic methods afforded trans-N-methyl-5-hydroxypipecolic acid, epicatechin, and proanthocyanidin A2 as the main constituents. Epicatechin and proanthocyanidin A2 showed potent DPPH radical scavenging activity, with IC₅₀ values of 18.34 and 11.45?μg/mL, respectively. A new compound, trans-N-methyl-5-hydroxypipecolic acid, did not show any antioxidant effect (IC₅₀?>?500?μg/mL).     

Anti-inflammatory,free radical scavenging and alpha-glucosidase inhibitory activities of Hamelia patens and its chemical constituents

Context Hamelia patens Jacq. (Rubiaceae) is traditionally used to treat wounds, inflammation and diabetes. However, there is still a lack of scientific evidence to support these applications.

Objective The objective of this study is to evaluate the anti-inflammatory, antioxidant and antidiabetic activities of Hamelia patens, and identify its bioactive compounds.

Materials and methods Four extracts were obtained by maceration and liquid–liquid extraction: HEX, DCM–EtOAc, MeOH–EtOAc and MeOH–Aq. The anti-inflammatory effect was evaluated orally on rat paw carrageenan-induced oedema over 6?h (50, 200 and 500?mg/kg), and topically in mouse ear oedema induced by 12-tetradecanoylphorbol-13-acetate (TPA) after 4?h (0.5 and 1?mg/ear). We also evaluated myeloperoxidase levels in ear tissue, 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging ability, and in vitro α-glucosidase inhibition. The chemical compounds were separated by column chromatography and identified by spectroscopic analysis.

Results We found that the oral administration of the HEX extract at 500 and 200?mg/kg significantly decreased the carrageenan-induced inflammation after 1 and 3?h, respectively. The MeOH–EtOAc extract significantly inhibited myeloperoxidase activity (83.5%), followed by the DCM–EtOAc extract (76%), β-sitosterol/stigmasterol (72.7%) and the HEX extract (55%), which significantly decreased oedema induced by TPA at both doses, giving a similar effect to indomethacin. We also found that the MeOH–EtOAc, MeOH–Aq and DCM–EtOAc extracts showed good DPPH scavenging activity (IC₅₀ values of 18.6, 93.9 and 158.2?μg/mL, respectively). The HEX extract showed the lowest α-glucosidase inhibition (an IC₅₀ value of 26.07?μg/mL), followed by the MeOH–EtOAc extract (an IC₅₀ value of 30.18?μg/mL), β-sitosterol/stigmasterol (IC₅₀ 34.6?μg/mL) and compound A ((6E,10E,14E,18E)-2,6,10,14,18,23-hexamethyl-2,6,10,14,18,22-tetracosahexaene, an IC₅₀ value of 114.6?μg/mL), which were isolated for the first time from Hamelia patens.

Discussion and conclusion Hamelia patens possesses anti-inflammatory, antioxidant and α-glucosidase inhibitory activities, which support its traditional use. These effects can be attributed to the identified compounds.     

Antioxidant Activities of Plants Used in Traditional Medicine in Turkey

Ethanol extracts from 6 species representing six different families, used in traditional medicine in Turkey were evaluated for their antioxidant activities. The inhibition of superoxide anion formation and lipid peroxidation levels of Ononis spinosa, Centranthus longiflorus, Lythrum salicaria, Plantago major, Juglans regia and Teucrium polium extracts were tested using in vitro standard procedures and IC₅₀ values were determined. In vitro tests included superoxide anion radical scavenging activity and lipid peroxidation. All ethanol extracts of plants showed concentration-dependent superoxide anion radical scavenging activity. The results of the superoxide anion formation assay showed that the ethanol extract of Centranthus longiflorus was found to be most potent inhibitor (IC₅₀ 0.77?mg/ml) and followed by Plantago major (IC₅₀ 1.21?mg/ml), Juglans regia (IC₅₀ 1.39?mg/ml), Ononis spinosa (IC₅₀ 1.35?mg/ml), Teucrium polium (IC₅₀ 3.10?mg/ml) and Lythrum salicaria (IC₅₀ 5.00?mg/ml). All the extracts, excluding Ononis spinosa and Teucrium polium, showed concentration-dependent inhibitory effect on lipid peroxidation. IC₅₀ values of the effective ethanol extracts of plants on lipid peroxidation were as follows: Juglans regia (IC₅₀ 3.3?mg/ml), Plantago major (IC₅₀ 3.4?mg/ml), Centranthus longiflorus (IC₅₀ 3.9?mg/ml) and Lythrum salicaria (IC50 5.3?mg/ml). The results showed that Centranthus longiflorus, Plantago major and Juglans regia extracts had the highest antioxidant capacities among the six species examined.     

Unlocking the in vitro anti-inflammatory and antidiabetic potential of Polygonum maritimum

Context: Several Polygonum species (Polygonaceae) are used in traditional medicine in Asia, Europe and Africa to treat inflammation and diabetes.

Objective: Evaluate the in vitro antioxidant, anti-inflammatory and antidiabetic potential of methanol and dichloromethane extracts of leaves and roots of the halophyte Polygonum maritimum L.

Material and methods: Antioxidant activity was determined (up to 1?mg/mL) as radical-scavenging activity (RSA) of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), copper (CCA) and iron (ICA) chelating activities and iron reducing power (FRAP). NO production was measured in lipopolysaccharide (LPS)-stimulated macrophages for 24?h at concentrations up to 100?μg/mL and antidiabetic potential was assessed by α-amylase and α-glucosidase inhibition (up to 10?mg/mL) assays. The phytochemical composition of the extracts was determined by gas chromatography-mass spectrometry (GC-MS).

Results: The methanol leaf extract had the highest activity against DPPH? (IC₅₀ =?26?μg/mL) and ABTS⁺? (IC₅₀ =?140?μg/mL), FRAP (IC₅₀ =?48?μg/mL) and CCA (IC₅₀ =?770?μg/mL). Only the dichloromethane leaf extract (LDCM) showed anti-inflammatory activity (IC₅₀ =?48?μg/mL). The methanol root (IC₅₀ =?19?μg/mL) and leaf (IC₅₀ =?29?μg/mL) extracts strongly inhibited baker’s yeast α-glucosidase, but LDCM had higher rat’s α-glucosidase inhibition (IC₅₀ =?2527?μg/mL) than acarbose (IC₅₀ =?4638?μg/mL). GC-MS analysis identified β-sitosterol, stigmasterol, 1-octacosanol and linolenic acid as possible molecules responsible for the observed bioactivities.

Conclusions: Our findings suggest P. maritimum as a source of high-value health promoting commodities for alleviating symptoms associated with oxidative and inflammatory diseases, including diabetes.     

Antioxidant activity of different parts of Tetrataenium lasiopetalum

Abstract

Context: In Iranian traditional medicine, different species of the genus Tetrataenium are used as antiseptic, spice and food additives.

Objective: The present study examined the possible antioxidant effects of hydro-alcoholic extracts of different parts of Tetrataenium lasiopetalum (Boiss.) Manden (Apiaceae).

Materials and methods: Laminas, stems, petioles, fruits, peduncles and flowers of T. lasiopetalum were collected, dried and then extracted by ethanol and water (70:30). Antioxidant activities of extracts were examined by employing different in vitro assays, i.e., 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, metal chelating, reducing power activities and hemoglobin-induced linoleic acid system. Also, total phenolic and flavonoid contents of the extracts were evaluated.

Results: Hydro-alcoholic extract of T. lasiopetalum flower showed the highest activity in scavenging of DPPH (IC₅₀?=?170?±?7?μg/mL). In metal chelating assay, lamina extract possesses a better iron ion chelating activity than other extracts (230?±?10?μg/mL). Lamina hydro-alcoholic extract demonstrated better activity in reducing the power and hemoglobin-induced linoleic acid system than other parts of T. lasiopetalum.

Discussion and conclusion: These results showed the antioxidant activity of different parts of T. lasiopetalum based on its usage in traditional medicine.     

LC-MS–MS and GC-MS analyses of biologically active extracts and fractions from Tunisian Juniperus phoenice leaves

Context: Despite some studies related to Juniperus phoenicea L. (Cupressaceae), phytochemical and biological investigations of this plant remain unexplored.

Objective: This work is the first report dealing with the identification and characterization of volatile components and flavonoids in hexane and methanol extracts from J. phoenicea leaves

Materials and methods: Antioxidant activity of hexane, and methanol extracts from J. phoenicea leaves were determined by DPPH-radical scavenging assay. α-Amylase inhibitory activity was evaluated by enzyme inhibition using in vitro assay (each extract was dissolved in DMSO to give concentrations of 50, 100 and 200?mg/mL). The chemical composition of fractions (Fr1-Fr3) from methanol extract was determined by high-performance liquid chromatography coupled with mass spectroscopy (HPLC-MS) analysis.

Results and discussion: The hexane extract was analyzed by GC-MS technique which allowed the identification of 32 compounds. The main constituents were α-humulene (16.9%), pentadecane (10.2%) and α-cubebene (9.7%). Fraction Fr 2 exhibited a strong DPPH radical-scavenging activity (IC_50?=_?20.1?μg/mL) compared to that of BHT as well as the highest α-amylase inhibitory activity (IC_50?=_?28.4?μg/mL). Three flavonoids were identified in these fractions using HPLC-MS analysis: Quercetin 3-O-glucoside, isoscutellarein 7-O-pentoside and quercetin 3-O-pentoside. In addition, the more active fraction (Fr 2) was purified with semi-preparative HPLC affording one pure compound (amentoflavone) using ¹H NMR analysis. This compound exhibited powerful DPPH radical-scavenging (IC_50?=_?14.1?μg/mL) and α-amylase inhibition (IC_50?=_?20.4?μg/mL) effects.

Conclusion: This study provides scientific support to some medicinal uses of J. phoenicea found in North Africa.     

Antimalarial and free radical scavenging activities of rhizomes of Polygonatum verticillatum supported by isolated metabolites

Antimalarial activity of the crude extract of Polygonatum verticillatum rhizomes and its sequentially partitioned fractions were investigated against Plasmodium falciparum. The crude extract possessed notable activity (IC₅₀: 21.67?μg/mL) that enhanced reasonably upon fractionation. The antiparasitic potency of the n-hexane fraction was maximum (IC₅₀: 2.33?μg/mL) followed by chloroform (IC₅₀: 4.62?μg/mL). However, the remaining fractions showed insignificant activity in the assay. The extracts of the plant showed marked scavenging activity on stable free radical, DDPH. The most potent antioxidant was the chloroform fraction (IC₅₀: 90?μg/mL) followed by ethyl acetate (IC₅₀: 93?μg/mL) and n-butanol (IC₅₀: 95?μg/mL) fractions. In the brine shrimps lethality test, the extracts were found nontoxic with the exception of ethyl acetate fraction (LD₅₀: 492.846?μg/mL). The bioactivity-guided isolation resulted into 5-hydroxymethyl-2-furaldehyde (HMF) and diosgenin which strongly supports the present experimental findings.     

In vitro assessment of selected Korean plants for antioxidant and antiacetylcholinesterase activities

Context: Antiacetylcholinesterase (AChE) drugs have been a main therapeutic treatment for Alzheimer’s disease because increased AChE levels play a key role in reducing neurotransmission.

Objectives: Extracts from 35 Korean plants were selected and screened for antioxidant and anti-cholinesterase activity to explore new sources derived from Korean natural resources that could be used as AD therapeutic agents.

Materials and methods: The antioxidant effect of extracts from 35 selected Korean plants was determined using two most common free radical scavenging assays using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS). Additionally, the effect of extracts, identified as antioxidants, on acetylcholinesterase inhibition was assessed by an acetylcholinesterase assay kit.

Results: Out of 36 extracts of 35 plants tested, Oenothera biennis L. (9.09?μg/mL), Saururus chinensis (Lour.) Baill. (9.52?μg/mL) and Betula platyphylla var. japonica (9.85?μg/mL) showed strong DPPH scavenging activity. Twelve other extracts also exerted moderate free radical scavenging activities with IC₅₀ values ranging from 10 to 50?μg/mL. Antioxidant capacity detected by ABTS assay was only significant in O. biennis (23.40?μg/mL), while the other extracts were weak or unable to reduce the production of ABTS. Based on the antioxidant activities of these plant extracts, 19 extracts with IC₅₀ values less than 100?μg/mL in DPPH assay were selected for further AChE inhibition assay. Among the extracts tested, the IC₅₀ value for Prunella vulgaris var. lilacina NAKAI (18.83?μg/mL) in AChE inhibitory activity was the lowest, followed by O. biennis (20.09?μg/mL) and Pharbitis nil Chosy (22.79?μg/mL).

Conclusions: Considering complex multifactorial etiology of AD, the extracts of P. vulgaris var. lilacina (aerial part), O. biennis (seed) and P. nil (seed) may be safe and ideal candidates for future AD modifying therapies.     

The mutagenic,antimutagenic and antioxidant properties of Hypericum lydium

Context: There is a growing market demand for Hypericum sp., a pharmacologically active plant that has been traditionally used to treat various ailments. However, there have been limited studies on the extract or essential oil of Hypericum lydium Boiss (Hypericaceae).

Objective: This study investigates for the first time the antioxidant, mutagenic and antimutagenic activity of an ethanol extract of H. lydium.

Material and methods: Ethanol extract from aerial parts of H. lydium harvested from Turkey were tested for this mutagenic and antimutagenic activities (2.0–0.002?mg/plate) using Ames Salmonella/microsome test system. 4-Nitro-o-phenylenediamine (4-NPD) (3?μg/plate) for the Salmonella typhimurium TA98 and sodium azide (NaN₃) (8?μg/plate) for the S. typhimurium TA100 were used as positive controls. The antioxidant activity, total antioxidant activity and phenolic constituent of the extract (2.0–0.002?mg/mL) was determined by the inhibition of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), β-carotene-linoleic acid model and by means of Folin–Ciocalteu reagent, respectively.

Results: The extract showed no sign of mutagenicity at the tested concentrations (0.002–2.0?mg/mL), and showed concentration-dependent antimutagenic activity against NaN₃ and 4-NPD ranging from 26.8 to 81.5%. The extract was found to be an efficient scavenger of DPPH (IC₅₀ 0.165?±?0.23?mg/mL) and to inhibit β-carotene-linoleic acid bleaching (IC₅₀ 0.39?±?0.11?mg/mL).

Discussion and conclusion: These findings indicate ethanol extract of H. lydium to be a safe and effective agent that may be incorporated into new strategies for the prevention of cancer and mutagenesis.