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.     

Treatment of Helicobacter pylori infected mice with Bryophyllum pinnatum,a medicinal plant with antioxidant and antimicrobial properties,reduces bacterial load

Context: Bryophyllum pinnatum (Lam.) Kurz (Crassulaceae) is a plant known for its antiulcer properties.

Objective: This study evaluates the anti-Helicobacter pylori activity of Bryophyllum pinnutum methanol extract with a mouse model and its antioxidant properties.

Materials and methods: Dried leaves of Bryophyllum pinnutum were extracted with methanol and ethyl acetate. Broth microdilution method was used to evaluate the anti-Helicobacter activity of extract samples in vitro. Swiss mice were inoculated with a suspension of Helicobacter pylori and divided into control group and four others that received 125, 250, 500?mg/kg of methanol extract or ciprofloxacin (500?mg/kg), respectively, for 7 days. Helicobacter pylori colonization and bacterial load of mouse stomach was assessed on day 1 and 7 post-treatment. The antioxidant activity of Bryophyllum pinnutum was evaluated through DPPH radical, hydroxyl radical and reducing power assay.

Results: Methanol extract showed a significant anti-Helicobacter activity with MIC and MBC values of 32 and 256?μg/mL, respectively. Bryophyllum pinnatum and ciprofloxacin reduced H. pylori colonization of gastric tissue from 100% to 17%. Bryophyllum pinnatum extract (85.91?±?52.91 CFU) and standard (25.74?±?16.15 CFU) also reduced significantly (p?50 values of 25.31?±?0.34, 55.94?±?0.68 and 11.18?±?0.74?μg/mL, respectively.

Discussion and conclusion: The data suggest that the methanol extract of Bryophyllum pinnatum could inhibit Helicobacter pylori growth, and may also acts as an antioxidant to protect gastric mucosa against reactive oxygen species.     

Antioxidant capacity of Typha angustifolia extracts and two active flavonoids

Context: The pollen of Typha angustifolia L. (Typhaceae) has been used as a traditional Chinese medicine for improving the microcirculation and promoting wound healing. Flavonoids are the main constituent in the plant, but little is known about the antioxidant activity of the principal constituent of the pollen in detail.

Objectives: To assess the antioxidant activities of ethanol and water extracts and two constituents of the pollen.

Materials and methods: Plant material (1?g) was extracted by 95% ethanol and water (10?mL?×?2, 1?h each), respectively. The extracted activities (0.8–2.6?mg/mL) were measured by DPPH and the reducing activity of ferric chloride (1.7–2.6?mg/mL). Typhaneoside and isorhamnetin-3-O-neohesperidoside (I3ON) (2.8–70?μmol/L) were investigated on the relationship between NO, MDA and SOD in HUVECs treated with 100?μg/mL of LPS for 24?h.

Results: Nine compounds were identified by UPLC-MS. Ethanol extract showed IC₅₀ values in DPPH (39.51?±?0.72) and Fe³⁺ reducing activity (82.76?±?13.38), higher than the water extract (50.85?±?0.74) and (106.33?±?6.35), respectively. Typhaneoside and I3ON promoted cell proliferation at the respective concentration range of 2.8 to 70?μmol/L (p?p?p?p?Conclusions: The constituents from Typha angustifolia could be a novel therapeutic strategy for LPS-induced inflammation.     

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.     

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.     

Antioxidant and anticholinesterase activities of five wild mushroom species with total bioactive contents

Abstract

Context: Recently, mushrooms are interesting natural products to be investigated due to exhibiting various bioactivities.

Objective: This study determines the antioxidant and anticholinesterase activities of various extracts of five wild mushroom species. In addition, the total bioactive contents, namely, ascorbic acid, β-carotene, and lycopene along with phenolic and flavonoid contents were also determined spectrophotometrically.

Materials and methods: Antioxidant activity was tested by using five complementary tests; namely, β-carotene-linoleic acid, DPPH^? scavenging, ABTS^?+ scavenging, cupric-reducing antioxidant capacity (CUPRAC), and metal chelating assays. The in vitro anticholinesterase activity was tested against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes using the Ellman method. The spectrophotometric methods were used to determine the total phenolic, flavonoid, ascorbic acid, β-carotene, and lycopene contents.

Results: The current study has shown that ethyl acetate extracts of Ganoderma lucidum (Curtis) P. Karst (IC₅₀: 1.55?±?0.05?µg/mL) and Funalia trogii (Berk.) Bondartsev & Singer (IC₅₀: 4.31?±?0.18?µg/mL) exhibited good lipid peroxidation inhibitory activity. The DPPH, ABTS, and CUPRAC assays supported this activity. The ethyl acetate and methanol extracts of Funalia trogii and Ganoderma lucidum indicated good anticholinesterase activity. Ganoderma lucidum had rich phenolic and flavonoid contents, indicating 98.67?±?0.32?mg PEs/g extract and 160.38?±?1.25?mg QEs/g extract, respectively.

Discussion and conclusion: The results demonstrate that some of the mushroom species tested herein could be used in food and pharmaceutical industries as natural antioxidants.     

Biological activities of ethyl acetate extract of different parts of Hyssopus angustifolius

Context: Hyssopus angustifolius M. Bieb. (Lamiaceae) is one of the most important medicinal plants in Iranian traditional medicine for the treatment of lung inflammation, laryngitis and cough relief. Much attention has been paid to this medicinal plant because of its traditional uses.

Objective: The present study examined the antioxidant and antihemolytic activities of ethyl acetate extract of stems, leaf and flowers of Hyssopus angustifolius.

Materials and methods: Antioxidant activity of extracts was evaluated by employing six different models, i.e., DPPH, nitric oxide and hydrogen peroxide scavenging, metal chelating and reducing power activities and hemoglobin-induced linoleic acid system. Also, antihemolytic activity was evaluated against hydrogen peroxide-induced hemolysis.

Results: Flowers extract showed the better activity than leaf and stems extracts in DPPH radical scavenging activity (IC₅₀ was 275.4?±?7.6 μg mL^?1). Leaf, stems and flowers extracts showed good nitric oxide scavenging activity (IC₅₀ were 376.6?±?11.4 µg mL^?1 for flowers, 297.6?±?9.6 μg mL^?1 µg mL^?1 for leaves and 837.8?±?19.2 µg mL^?1 for stems). The leaf extract exhibited better hydrogen peroxide scavenging and Fe²⁺ chelating activity than stems and flowers extracts. In hemoglobin-induced linoleic acid system, all of the extracts exhibited very good activity. Also, extracts show weak reducing power activity. The ethyl acetate extract of leaf showed better antihemolytic activity than the flower and stems (IC₅₀ was 94.0?±?2.4 μg mL^?1).

Discussion and conclusion: These findings give a scientific basis to the traditional usage of Hyssopus angustifolius, also showing its potential as rich sources of natural antioxidant compounds.     

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.     

Geographic origin influences the phenolic composition and antioxidant potential of wild Crataegus monogyna from Spain

Context: Crataegus monogyna Jacq L. (Lind.) (Rosaceae) is used in folk medicine as a sedative, aerial parts being rich in polyphenols with antioxidant ability.

Objectives: To study the variation in polyphenolic composition and antioxidant ability of spontaneous samples of C. monogyna in order to assess the relationship among these variables.

Materials and methods: Aerial parts of C. monogyna were collected from nine different locations in central Spain and extracted with methanol after drying. Total polyphenols were determined by the Folin-Ciocalteu method using gallic acid (GA) as standard. Sixteen polyphenolic compounds (11 flavonoids and 5 phenolic acids) were identified and quantified by reversed-phase HPLC in one single analysis. The antioxidant ability was evaluated by the oxygen radical absorbance capacity (ORAC) and the free radical scavenging activity (DPPH) methods. Linear correlation analysis was used to explore the relationships between the studied variables.

Results: Total polyphenol content ranged between 117.729?±?0.011 and 204.286?±?0.015?mg GAE/g extract, depending on the geographic origin. No relationship was found between total polyphenols and antioxidant ability by the ORAC or DPPH methods. Chromatographic analysis yielded lower amounts of polyphenols (23.3–143.26?mg/kg), as only flavonoids and phenolic acids were quantified. All the samples exhibited antioxidant activity between 1.32?±?0.08 and 2.76?±?0.007?μmol Trolox equivalents/mg and IC₅₀ from 0.82?±?0.10 to 3.76?±?0.67?μg/mL.

Conclusion: A statistically significant relationship between flavonoids and phenolic acids content and the antioxidant potential obtained by the ORAC method for C. monogyna samples was proven.     

Anticholinesterase,antioxidant, analgesic and anti-inflammatory activity assessment of Xeranthemum annuum L. and isolation of two cyanogenic compounds

Context: Xeranthemum annuum L. (Asteraceae) (XA) is an ornamental and medicinal species with limited bioactivity and phytochemical data.

Objective: Identification of anticholinesterase, antioxidant, anti-inflammatory and analgesic effects of the flower and root–stem (R-S) extracts of XA.

Materials and methods: Anticholinesterase (at 100?μg mL^?1) and antioxidant (at 1000?μg mL^?1) effects of various extracts were evaluated via microtiter assays, while anti-inflammatory and analgesic effects of the R-S extracts were tested using carrageenan-induced hind paw oedema (100 and 200?mg kg^?1) and p-benzoquinone (PBQ) writhing models (200?mg kg^?1) in male Swiss albino mice. The R-S ethanol extract of XA was subjected to isolation studies using conventional chromatographic methods.

Results: Most of the extracts showed inhibition over 85% against butyrylcholinesterase and no inhibition towards acetylcholinesterase. The flower chloroform and the R-S ethyl acetate extracts were most effective (97.85?±?0.94% and 96.89?±?1.09%, respectively). The R-S ethanol extract displayed a remarkable scavenging activity against DPPH (77.33?±?1.99%) and in FRAP assay, while the hexane extract of the R-S parts possessed the highest metal-chelating capacity (72.79?±?0.33%). The chloroform extract of the R-S caused a significant analgesic effect (24.4%) in PBQ writhing model. No anti-inflammatory effect was observed. Isolation of zierin and zierin xyloside, which were inactive in anticholinesterase assays, was achieved from the R-S ethanol extract.

Discussion and conclusion: This is the first report of anticholinesterase, antioxidant, analgesic and anti-inflammatory activities and isolation of zierin and zierin xyloside from XA. Therefore, XA seems to contain antioxidant and BChE-inhibiting compounds.     

Antioxidant activities and molecular mechanisms of the ethanol extracts of Baccharis propolis and Eucalyptus propolis in RAW64.7 cells

Context Numerous studies have reported that propolis possesses strong antioxidant activities. However, their antioxidant molecular mechanisms are unclear.

Objective We utilize ethanol extracts of Chinese propolis (EECP) as a reference to compare ethanol extracts of Eucalyptus propolis (EEEP) with ethanol extracts of Baccharis propolis (EEBGP) based on their antioxidant capacities and underlying molecular mechanisms.

Materials and methods HPLC and chemical analysis are utilized to evaluate compositions and antioxidant activities. ROS-eliminating effects of EEBGP (20–75?μg/mL), EEEP (1.25–3.75?μg/mL) and EECP (1.25–5?μg/mL) are also determined by flow cytometry analysis. Moreover, we compared antioxidant capacities by determining their effects on expressions of antioxidant genes in RAW264.7 cells with qRT-PCR, western blot and confocal microscopy analysis.

Results EEBGP mainly contains chlorogenic acid (8.98?±?0.86?mg/g), kaempferide (11.18?±?8.31?mg/g) and artepillin C (107.70?±?10.86?mg/g), but EEEP contains 10 compositions, whereas EECP contains 17 compositions. Meantime, although EEEP shows DPPH (IC₅₀ 19.55?±?1.28), ABTS (IC₅₀ 20.0?±?0.31) and reducing power (2.70?±?0.08?mmol TE/g) better than EEBGP’s DPPH (IC₅₀ 43.85?±?0.54), ABTS (IC₅₀ 38.2?±?0.33) and reducing power (1.53?±?0.05?mmol TE/g), EEBGP exerts much higher ROS inhibition rate (40%) than EEEP (under 20%). Moreover, EEBGP strengthen antioxidant system by activating p38/p-p38 and Erk/p-Erk kinase via accelerating nucleus translocation of Nrf2. EEEP and EECP improve antioxidant gene expression only via Erk/p-Erk kinase-Nrf2 signalling pathway.

Discussion and conclusion EEBGP and EEEP exert antioxidant activities via different molecular mechanisms, which may depend on chemical compositions.     

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.     

Characterization of the natural products in cocoyam (Colocasia esculenta) using GC–MS

Context: There is paucity of information in literature on the natural products in cocoyam [Colocasia esculenta Linn (Araceae)] that confer it with biological properties.

Objectives: This study investigated the antioxidant properties of C. esculenta and also reported for the first time the natural products in C. esculenta that justify its biological properties.

Materials and methods: The antioxidant activity of the methanol extract (50–250?μg/mL) of C. esculenta was determined using the 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical and reducing power assays. Characterization of the natural products in C. esculenta was done using the gas chromatographic–mass spectrometric (GC–MS) technique. The experiment lasted for 3 months.

Results: GC–MS analysis of methanol/chloroform extract of the flour of C. esculenta indicated the presence of eight compounds, namely hexadecanoic acid methyl ester (0.43%), octadecanoic acid (20.91%), 9,12-octadecadienoyl chloride (0.77%), 11-octadecenoic acid methyl ester (2.12%), 9-octadecenoic acid (64.37%), 3-hexadecyloxycarbonyl-5-(2-hydroxylethyl)-4-methylimidazolium(1.36%), hexanedioic acid, bis(2-ethylhexyl)ester (1.36%) and 3,5-di-t-butyl phenol (3.27%). The total phenolic content of C. esculenta was 15.15?±?0.35?mg Gallic Acid Equivalence/g and it was significantly higher (p?<?0.05) than the total flavonoid (8.50?±?0.42?mg Quercetin Equivalence/g) and condensed tannin (4.40?±?0.14?mg Catechin Equivalence/g) contents, respectively. C. esculenta possessed strong antioxidant capacity though it was lower than that of standard quercetin.

Discussion and conclusion: Results showed that C. esculenta possesses strong antioxidant activity and also contains some important bioactive compounds that justify its medicinal properties as used in ethno-medicine.     

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.     

Quantitative analysis of rutin,quercetin, naringenin,and gallic acid by validated RP- and NP-HPTLC methods for quality control of anti-HBV active extract of Guiera senegalensis

Context: Guiera senegalensis J.F. Gmel (Combretaceae) is a folk medicinal plant used in various metabolic and infectious diseases. In addition to its antiviral activities against herpes and fowlpox, the anti-HBV efficacy is very recently reported.

Objective: To develop and validate simple, sensitive RP-/NP-HPTLC methods for quantitative determination of biomarkers rutin, quercetin, naringenin, and gallic acid in the anti-HBV active G. senegalensis leaves ethanol-extract.

Materials and methods: RP-HPTLC (rutin &; quercetin; phase- acetonitrile:water, 4:6) and NP-HPTLC (naringenin &; gallic acid; phase- toluene:ethyl acetate:formic acid, 6:4:0.8) were performed on glass-backed silica gel plates 60F₂₅₄-RP18 and 60F₂₅₄, respectively. The methods were validated according to the ICH guidelines.

Results: Well-separated and compact spots (R_f) of rutin (0.52?±?0.006), quercetin (0.23?±?0.005), naringenin (0.56?±?0.009) and gallic acid (0.28?±?0.006) were detected. The regression equations (Y) were 12.434x?+?443.49, 10.08x?+?216.85, 11.253x?+?973.52 and 11.082x?+?446.41 whereas the coefficient correlations (r²) were 0.997?±?0.0004, 0.9982?±?0.0001, 0.9974?±?0.0004 and 0.9981?±?0.0001, respectively. The linearity ranges (ng/spot) were 200–1400 (RP-HPTLC) and 100–1200 (NP-HPTLC). The LOD/LOQ (ng/band) were 33.03/100.1 (rutin), 9.67/29.31 (quercetin), 35.574/107.8 (naringenin), and 12.32/37.35 (gallic acid). Gallic acid (7.01?μg/mg) was the most abundant biomarker compared to rutin (2.42?μg/mg), quercetin (1.53?μg/mg) and naringenin (0.14?μg/mg) in the extract.

Conclusion: The validated NP-/RP-HPTLC methods were simple, accurate, and sensitive for separating and quantifying antiviral biomarkers in G. senegalensis, and endorsed its anti-HBV activity. The developed methods could be further employed in the standardization and quality-control of herbal formulations.     

Antioxidant properties of Ferulago angulata and its hepatoprotective effect against N-nitrosodimethylamine-induced oxidative stress in rats

Context: Ferulago angulata (Schlecht.) Boiss. (Apiaceae) (FASB) is used to treat liver diseases and has been used both as food and therapeutics by many cultures for thousands of years because of the natural antioxidant compounds.

Objective: This study determines antioxidant properties of FASB flowers, the levels of minerals and vitamins, and also, evaluates the hepatoprotective effect of flowers against N-nitrosodimethylamine (NDMA) induced on liver tissue by assessing antioxidant enzymes and histopathological parameters in Wistar albino rats.

Materials and methods: In the study, the rats were divided into six groups of ten. Control, untreated animals were given 0.9% NaCl. Rats were intraperitoneally given NDMA (10?mg/kg) for the first 7 days. FASB methanol extract (150 and 300?mg/kg) was administered orally for 21 days.

Results: α-Tocopherol, retinol, ascorbic acid, total antioxidant activity, phenolic and flavonoid contents of FASB were 0.70?±?0.13, 0.29?±?0.03?μg/g, 139.32?±?7.06?μg/100?g, 171.61?±?6.05?mM ascorbic acid/g, 90.47?±?4.11?mg GA/g and 37.39?±?2.85?mg QE/g. DPPH and hydroxyl radical scavenging activity was obtained IC₅₀ 67.34?±?4.14 and 64.87?±?4.68?μg/mL, respectively.

Discussion and conclusion: The results of the study indicated that FASB flowers contain high levels of vitamins, minerals, total antioxidant activity, phenolics and flavonoids. Due to the positive effect on significant changes in antioxidant enzymes of liver tissue and histopathological examination, it is thought that the plant could be used as a hepatoprotective.     

Antioxidant and anti-cholinesterase activity of Sargassum wightii

Abstract

Context. Sargassum has been used in traditional Chinese medicine since the eighth century AD to treat goiter. Sargassum wightii Greville (Sargassaceae) is a major source of alginic acid used widely in food and drug industries.

Objective: To evaluate the anti-Alzheimer potential of S. wightii through evaluation of antioxidant and cholinesterase inhibitory activities.

Materials and methods: Successive extraction was done using solvents of varying polarity. Solvent extracts (100–500?µg/mL) were employed for all the antioxidant assays. Free radical scavenging activity was evaluated by 2,2-diphenyl-1-picrylhydrazyl, OH?, H₂O₂ radical scavenging assay. The reducing power of the seaweed was evaluated by ferric reducing antioxidant power and reducing power assay. Cholinesterase (ChE) inhibitory activity was evaluated and the Km, Vmax and Ki were calculated. Further, compound characterization was done by GC-MS analysis.

Results: The non-polar extracts were found to possess significant antioxidant activity. At 100?μg/mL, petroleum ether, hexane, benzene and dichloromethane extracts showed significant ChE inhibitory activity with IC₅₀ values of 19.33?±?0.56, 46.81?±?1.62, 27.24?±?0.90, 50.56?±?0.90?µg/mL, respectively, for AChE, and 17.91?±?0.65, 32.75?±?1.00, 12.98?±?0.31, 36.16?±?0.64?µg/mL, respectively, for BuChE. GC-MS reveals that 1,2-benzenedicarboxylic acid, diisooctyl ester is the major compound present in dichloromethane extract of S. wightii. The mode of inhibition exhibited by dichloromethane extract against the cholinesterases was found to be competitive type.

Discussion and conclusion: The presence of high amount of terpenoids could be the possible reason for its potential antioxidant and ChE inhibitory activity.     

Flavonoids,cytotoxic, antioxidant and antibacterial activities of Evax pygmaea

Context: Phytochemical study and biological potential of Evax pygmaea (L.) Brot. (Asteraceae) are reported for the first time.

Objective: To identify the secondary metabolites of Evax pygmaea and to determine its antioxidant, antibacterial and cytotoxic activities.

Materials and methods: Dried aerial parts (1?kg) were macerated in 70% MeOH (5?L) during 72?h. The concentrated hydromethanolic extract was subjected to extractions with chloroform (3?×?300?mL), ethyl acetate (3?×?300?mL) and n-butanol (3?×?300?mL), successively. VLC of combined ethyl acetate (EAEP) and n-butanol (BEP) fractions was followed by column purifications. Antioxidant activity was investigated using DPPH, CUPRAC, and metal chelating, β-carotene/linoleic acid and ABTS assays. Agar method was used in the antibacterial study. Cytotoxic activity was determined by Brine shrimp lethality test in DMSO and ethanol, at varying concentrations (2, 1 and 0.2%) and (1, 0.2 and 0.1%) successively.

Results: Quercetin (1), isorhamnetin 3-O-β-d-xyloside (2), isorhamnetin 3-O-β-d-glucoside (3), quercetin 3-O-β-d-glucoside (4), quercetin 7-O-β-D-glucoside (5), patuletin 3-O-β-d-glucoside (6) were isolated from for the first time from Evax genus. The EAEP was the most active in ABTS (IC₅₀: <3.125?μg/mL) assay whereas the BEEP exhibited the highest activity in the β-carotene/linoleic acid assay (IC₅₀: <3.125?μg/mL). The EAEP and BEP exhibited good antibacterial activity (MIC: 40–80 µg/mL). The plant did not show any toxicity (LD₅₀>80 µg/mL).

Discussion and conclusions: Six flavonoids were isolated for the first time from Evax pygmaea which exhibited good antioxidant and antibacterial activities.     

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.