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.     

Compounds from Sedum caeruleum with antioxidant,anticholinesterase, and antibacterial activities

Context: This is the first study on the phytochemistry, antioxidant, anticholinesterase, and antibacterial activities of Sedum caeruleum L. (Crassulaceae).

Objective: The objective of this study is to isolate the secondary metabolites and determine the antioxidant, anticholinesterase, and antibacterial activities of S. caeruleum.

Materials and methods: Six compounds (1–6) were isolated from the extracts of S. caeruleum and elucidated using UV, 1D-, 2D-NMR, and MS techniques. Antioxidant activity was investigated using DPPH^?, CUPRAC, and ferrous-ions chelating assays. Anticholinesterase activity was determined against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes using the Ellman method. Antibacterial activity was performed according to disc diffusion and minimum inhibitory concentration (MIC) methods.

Results: Isolated compounds were elucidated as ursolic acid (1), daucosterol (2), β-sitosterol-3-O-β-d-galactopyranoside (3), apigenin (4), apigetrin (5), and apiin (6). The butanol extract exhibited highest antioxidant activity in all tests (IC₅₀ value: 28.35?±?1.22?µg/mL in DPPH assay, IC₅₀ value: 40.83?±?2.24?µg/L in metal chelating activity, and IC₅₀ value: 23.52?±?0.44?µg/L in CUPRAC), and the highest BChE inhibitory activity (IC₅₀ value: 36.89?±?0.15?µg/L). Moreover, the chloroform extract mildly inhibited (MIC value: 80?µg/mL) the growth of all the tested bacterial strains.

Discussion and conclusion: Ursolic acid (1), daucosterol (2), β-sitosterol-3-O-β-d-galactopyranoside (3), apigenin (4), apigetrin (5), and apiin (6) were isolated from Sedum caeruleum for the first time. In addition, a correlation was observed between antioxidant and anticholinesterase activities of bioactive ingredients of this plant.     

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.     

Phytochemicals from Dodonaea viscosa and their antioxidant and anticholinesterase activities with structure–activity relationships

Context Dodonaea viscosa (L.) Jacq (Sapindaceae) has been used in traditional medicine as antimalarial, antidiabetic and antibacterial agent, but further investigations are needed.

Objective This study determines the antioxidant and anticholinesterase activities of six compounds (1–6) and two crystals (1A and 3A) isolated from D. viscosa, and discusses their structure–activity relationships.

Materials and methods Antioxidant activity was evaluated using six complementary tests, i.e., β-carotene-linoleic acid; DPPH^?, ABTS^?+, superoxide scavenging, CUPRAC and metal chelating assays. Anticholinesterase activity was performed using the Elman method.

Results Clerodane diterpenoids (1 and 2) and phenolics (3–6) – together with three crystals (1A, 3A and 7A) – were isolated from the aerial parts of D. viscosa. Compound 3A exhibited good antioxidant activity in DPPH (IC₅₀: 27.44?±?1.06?μM), superoxide (28.18?±?1.35% inhibition at 100?μM) and CUPRAC (A_0.5: 35.89?±?0.09?μM) assays. Compound 5 (IC₅₀: 11.02?±?0.02?μM) indicated best activity in ABTS assay, and 6 (IC₅₀: 14.30?±?0.18?μM) in β-carotene-linoleic acid assay. Compounds 1 and 3 were also obtained in the crystal (1A and 3A) form. Both crystals showed antioxidant activity. Furthermore, crystal 3A was more active than 3 in all activity tests. Phenol 6 possessed moderate anticholinesterase activity against acetylcholinesterase and butyrylcholinesterase enzymes (IC₅₀ values: 158.14?±?1.65 and 111.60?±?1.28?μM, respectively).

Discussion and conclusion This is the first report on antioxidant and anticholinesterase activities of compounds 1, 2, 5, 6, 1A and 3A, and characterisation of 7A using XRD. Furthermore, the structure–activity relationships are also discussed in detail for the first time.     

Evaluation of anti-inflammatory activity and standardisation of hydro-methanol extract of underground tuber of Dioscorea alata

Context The underground edible tuber of Dioscorea alata L. (Dioscoreaceae) is a functional food with high nutritive value and therapeutic potential. The tuber is known to possess anti-inflammatory properties in traditional medicine.

Objective The present study explores the anti-inflammatory activity and standardisation of D. alata tuber hydromethanol extract.

Materials and methods Hydromethanol extract (70%) of D. alata tuber was chemically characterised using HPLC and GC-MS techniques. Murine lymphocytes were cultured for 48?h with six different concentrations (0–80?μg/mL) of the extract. The expression of nitric oxide (NO), TNF-α, COX-1, COX-2, and PGE₂ were evaluated using colorimetric and ELISA methods.

Results Dioscorea alata extract inhibited the expression of NO and TNF-α with an IC₅₀ value of 134.51?±?6.75 and 113.30?±?7.44?μg/mL, respectively. The IC₅₀ values for inhibition of total COX, COX-1, COX-2 activities and PGE₂ level were 41.96?±?3.07, 141.41?±?8.99, 32.50?±?1.69, and 186.34?±?15.36?μg/mL, respectively. Inhibition of PGE₂ level and COX-2 activity was positively correlated (R²?=?0.9393). Gallic acid (GA), 4-hydroxy benzoic acid (4HBA), syringic acid (SYA), p-coumaric acid (PCA), and myricetin (MY) were identified and quantified using HPLC. GC-MS analysis revealed the presence of 13 different phytocompounds such as hexadecanoic acid, methyl stearate, cinnamyl cinnamate, and squalene.

Conclusion The D. alata extract significantly down-regulated the pro-inflammatory signals in a gradual manner compared with control (0?μg/mL). Different bioactive phytocompounds individually possessing anti-inflammatory activities contributed to the overall bioactivity of the D. alata tuber extract.     

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.     

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.     

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.     

Cholinesterase inhibitory,anti-amyloidogenic and neuroprotective effect of the medicinal plant Grewia tiliaefolia – An in vitro and in silico study

Context: Grewia tiliaefolia Vahl. (Tiliaceae) is a sub-tropical plant used as an indigenous medicine in India. However, its efficacy has not been evaluated against Alzheimer’s disease.

Objectives: The objective of this study is to evaluate cholinesterase inhibitory, anti-aggregation and neuroprotective activity of G. tiliaefolia.

Materials and method: Grewia tiliaefolia leaves were collected from Eastern Ghats region, India, and subjected to successive extraction (petroleum ether, chloroform, ethyl acetate, methanol and water). The extracts were subjected to in vitro antioxidant, anticholinesterase and anti-aggregation assays. The active methanol extract (MEGT) was separated using column chromatography. LC-MS analysis was done and the obtained compounds were docked against acetylcholinesterase (AChE) enzyme to identify the active component.

Results: Antioxidant assays demonstrated that the MEGT showed significant free radical scavenging activity at the IC₅₀ value of 71.5?±?1.12?μg/mL. MEGT also exhibited significant dual cholinesterase inhibition with IC₅₀ value of 64.26?±?2.56 and 54?±?0.7?μg/mL for acetyl and butyrylcholinesterase (BChE), respectively. Also, MEGT showed significant anti-aggregation activity by preventing the oligomerization of Aβ_25–35. Further, MEGT increased the viability of Neuro2a cells up to 95% against Aβ_25-35 neurotoxicity. LC-MS analysis revealed the presence of 16 compounds including vitexin, ellagic acid, isovitexin, etc. In silico analysis revealed that vitexin binds effectively with AChE through strong hydrogen bonding. These results were further confirmed by evaluating the activity of vitexin in vitro, which showed dual cholinesterase inhibition with IC₅₀ value of 15.21?±?0.41 and 19.75?±?0.16?μM for acetyl and butyrlcholinesterase, respectively.

Discussion and conclusion: Grewia tiliaefolia can be considered as a promising therapeutic agent for the treatment of AD.     

Neuroprotective effect of the marine macroalga Gelidiella acerosa: identification of active compounds through bioactivity-guided fractionation

Context Gelidiella acerosa (Forsskål) Feldmann & G. Hamel (Rhodophyta-Gelidiales) is a marine red macroalga. Our previous work found that a benzene extract of G. acerosa possesses noticeable neuroprotective activity, when evaluated through in vitro and in vivo systems.

Objective Bioactive-guided fractionation and identification of active compounds by column chromatography using solvents of varying polarity.

Materials and methods Fractionation was done by column chromatography, antioxidant and anticholinesterase activity was assessed by DPPH and cholinesterase inhibition assays (50–200?μg/ml), compound identification was done by LC-MS analysis, the mode of interaction of active compound was analyzed through docking studies and quantification was done by high-performance thin-layer chromatography (HPTLC) analysis.

Results The results suggest that fractions F9–F13 exhibited significant (p?<?0.05) antioxidant and anticholinesterase activities. Hence, these fractions were pooled together and verified for neuroprotective activity. The pooled fraction was subjected to LC-MS analysis and among all the compounds, phytol was previously reported to possess excellent neuroprotective potential. Hence, the neuroprotective potential of phytol was assessed. The results suggest that phytol showed significant (p?<?0.05) antioxidant activities (25–125?μg/ml) with an IC₅₀ value of 95.27?±?1.65?μg/ml and cholinesterase inhibitory potential (5–25?μg/ml) with IC₅₀ values of 2.704?±?0.07 and 5.798?±?0.72?μg/ml for AChE and BuChE, respectively. Molecular docking studies suggest that phytol interacts with cholinesterase through the arginine residue of the enzyme. HPTLC quantification showed that about 6.266?μg of phytol was present per mg of pooled fraction.

Conclusion The study suggests that phytol might act as the key compound in contributing to the neuroprotective potential of G. acerosa.     

Chemical composition and in vitro cytotoxic effects of the essential oil from Nectandra leucantha leaves

Abstract

Context: Nectandra (Lauraceae) species have been used in folk medicine as an antidiarrheal, analgesic, antifungal, etc., and have many pharmacological proprieties.

Objective: Investigation of the chemical composition and cytotoxicity of essential oil from Nectandra leucantha Nees & Mart. leaves. This is the first study involving N. leucantha reported in the literature.

Material and methods: The essential oil of N. leucantha leaves was obtained by hydrodistillation. Its chemical composition was determined using a combination of GC/FID, GC/MS, and determination of Kovats index (KI). In vitro cytotoxic activity was evaluated against six cancer cell lines – murine melanoma (B16F10-Nex2), human glioblastome (U-87), human cervical carcinoma (HeLa), human colon carcinoma (HCT), human breast adenocarcinoma (MCF7), and human cervical tumor (Siha) as well as against one non-tumorigenic cell line – human foreskin fibroblast (HFF).

Results: Thirty-three compounds were identified primarily sesquiterpenes (81.41%), the main compounds being bicyclogermacrene (28.44%), germacrene A (7.34%), spathulenol (5.82%), and globulol (5.25%). Furthermore, monoterpenes were also found in the analyzed oil (12.84%), predominantly α- and β-pinenes (6.59 and 4.57%, respectively). The crude essential oil displayed significant cytotoxic activity against B16F10-Nex2 (IC₅₀ 33?±?1?μg/mL) and U87 (IC₅₀ 75.95?±?0.03?μg/mL) and HeLa (IC₅₀ 60?±?12?μg/mL) cell lines. The main identified compound, bicyclogermacrene, displayed IC₅₀ ranging from 3.1?±?0.2 to 21?±?6?μg/mL.

Discussion and conclusion: The results indicate that the crude oils from leaves of N. leucantha displayed cytotoxic activity being bicyclogermacrene, the main compound identified in the crude oil responsible, at least in part, for this potential.     

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.     

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.     

Chemical composition,antioxidant and antibacterial activities of two Spondias species from Northeastern Brazil

Context: The leaves of Spondias tuberosa Arr. Cam. (Anacardiaceae) and Spondias mombin L. have been traditionally used for medicinal purposes. Some studies reveal their antibacterial, antimicrobial, and antiviral properties.

Objective: Determine the chemical composition, antioxidant, and antimicrobial activities of Spondias species to justify its ethnopharmacological use.

Materials and methods: Spondias species extracts were prepared with methanol:water 80:20 and analyzed by silica gel column chromatography and reversed phase liquid chromatography (HPLC). The antioxidant activity was evaluated by scavenging the radicals 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and 2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS?+) and measuring antimicrobial activity (agar well diffusion method, minimum inhibitory concentration and minimum bactericidal concentrations).

Results: The HPLC analysis of Spondias extracts demonstrated the occurrence of high yield of flavonoids. Found in S. mombin were quercetin (2.36?±?0.01?mg/g) and ellagic acid (41.56?±?0.01?mg/g) and in S. tuberosa species rutin (53.38?±?1.71?mg/g), quercetin (24.46?±?0.87?mg/g), and ellagic acid (169.76?±?0.17?mg/g). The antibacterial activity of the extracts against the various bacteria strains varied from 8.8 to 20.1?mm. MIC values from 62.5 to 125 µg/mL were satisfactory when compared with other plant products. Medium DPPH scavenging activity IC₅₀ for Spondias extracts varied from 0.042 to 0.558?mg/mL and for ABTS from 0.089 to 0.465?mg/mL. DPPH scavenging activity for constituent ellagic acid IC₅₀?=?0.042?mg/mL and for quercetin IC₅₀?=?0.081?mg/mL.

Discussion and conclusion: The chemical study of Spondias leaf extracts showed the occurrence of quercetin, rutin and ellagic acid, substances with relevant antioxidant and antimicrobial activities.     

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 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.     

Protective activity of Hertia cheirifolia extracts against DNA damage,lipid peroxidation and protein oxidation

Context: Hertia cheirifolia L. (Asteraceae), a perennial shrub widely distributed in Northern Africa, is traditionally used to treat inflammatory disorders.

Objective: The protective effect of methanol (Met E) and aqueous (Aq E) extracts of Hertia cheirifolia against DNA, lipid and protein oxidation was investigated.

Materials and methods: Different concentrations (50–1000?μg/mL) of Hertia cheirifolia aerial part extracts were examined against DNA, lipid and protein oxidation induced by H₂O_2?+?UV, FeSO₄, and Fe³⁺/H₂O₂-ascorbic acid, respectively. The DPPH^?, metal ion chelating, reducing power and β-carotene bleaching tests were conducted.

Results: Both extracts were rich in polyphenols, flavonoids and tannins, and were able to scavenge DPPH^? with IC₅₀ values of 138 and 197?μg/mL, respectively. At 300?μg/mL, Aq E exerted stronger chelating effect (99%) than Met E (69%). However, Met E reducing power (IC_50?=_?61?μg/mL) was more than that of Aq E (IC_50?=_?193?μg/mL). Both extracts protected from β-carotene bleaching by 74% and 94%, respectively, and inhibited linoleic acid peroxidation. The inhibitory activity of Aq E extract (64%) was twice more than that of Met E (32%). Interestingly, both extracts protected DNA against the cleavage by about 96–98%. At 1?mg/mL, Met E and Aq E restored protein band intensity by 94–99%.

Conclusions: Hertia cheirifolia exhibits potent antioxidant activity and protects biomolecules against oxidative damage; hence, it may serve as potential source of natural antioxidant for pharmaceutical applications and food preservation. This is the first report on the protective activity of this plant against biomolecule oxidation.     

Mechanism of action of relaxant effect of Agastache mexicana ssp.mexicana essential oil in guinea-pig trachea smooth muscle

Context: Agastache mexicana ssp. mexicana (Kunth) Lint &; Epling (Lamiaceae), popularly known as ‘toronjil morado’, is used in Mexican traditional medicine for the treatment of several diseases such as hypertension, anxiety and respiratory disorders.

Objective: This study investigates the relaxant action mechanism of A. mexicana ssp. mexicana essential oil (AMEO) in guinea-pig isolated trachea model.

Materials and method: AMEO was analyzed by GC/MS. The relaxant effect of AMEO (5–50?μg/mL) was tested in guinea-pig trachea pre-contracted with carbachol (3?×?10?^??⁶?M) or histamine (3?×?10?^??⁵?M) in the presence or absence of glibenclamide (10?^??⁵?M), propranolol (3?×?10?^??⁶?M) or 2′,5′-dideoxyadenosine (10?^??⁵?M). The antagonist effect of AMEO (10–300?μg/mL) against contractions elicited by carbachol (10?^??¹⁵–10?^??³?M), histamine (10?^??¹⁵–10?^??³?M) or calcium (10–300?μg/mL) was evaluated.

Results: Essential oil composition was estragole, d-limonene and linalyl anthranilate. AMEO relaxed the carbachol (EC_50?=_?18.25?±?1.03?μg/mL) and histamine (EC_50?=_?13.3?±?1.02?μg/mL)-induced contractions. The relaxant effect of AMEO was not modified by the presence of propranolol, glibenclamide or 2′,5′-dideoxyadenosine, suggesting that effect of AMEO is not related to β₂-adrenergic receptors, ATP-sensitive potassium channels or adenylate cyclase activation. AMEO was more potent to antagonize histamine (pA₂′?=??1.507?±?0.122) than carbachol (pA₂′?=??2.180?±?0.357). Also, AMEO antagonized the calcium chloride-induced contractions.

Conclusion: The results suggest that relaxant effect of AMEO might be due to blockade of calcium influx in guinea-pig trachea smooth muscle. It is possible that estragole and d-limonene could contribute majority in the relaxant effect of AMEO.     

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.     

Caffeic acid methyl and ethyl esters exert potential antidiabetic effects on glucose and lipid metabolism in cultured murine insulin-sensitive cells through mechanisms implicating activation of AMPK

Context: Caffeic acid methyl (CAME) and ethyl (CAEE) esters stimulate glucose uptake and AMP-activated protein kinase (AMPK) in C2C12 myocytes (ATCC^® CRL-1772^TM).

Objective: Effects of CAME and CAEE were now assessed on myocyte glucose transporter GLUT4 activity and expression, on hepatic gluconeogenesis and on adipogenesis as well as major underlying signaling pathways.

Materials and methods: GLUT4 protein translocation was studied in L6 GLUT4myc cells, glucose-6-phospatase (G6Pase) in H4IIE hepatocytes and adipogenesis in 3T3-L1 adipocytes. Key modulators were measured using western immunoblot. Cells were treated for 18?h with either CAME or CAEE at various concentrations (12.5–100?μM).

Results: Myocyte glucose uptake rose from 10.1?±?0.5 to 18.7?±?0.8 and 21.9?±?1.0?pmol/min/mg protein in DMSO-, CAME- and CAEE-stimulated cells, respectively, similar to insulin (17.7?±?1.2?pmol/min/mg protein), while GLUT4myc translocation increased significantly by 1.70?±?0.18, by 1.73?±?0.18- and by 1.95?±?0.30-fold (relative to DMSO), following insulin, CAME and CAEE stimulation, respectively. CAME and CAEE suppressed hepatocyte G6Pase by 62.0?±?6.9% and 62.7?±?6.0% with IC₅₀ of 45.93 and 22.64?μM, respectively, comparable to insulin (70.7?±?2.3% inhibition). Finally, CAME and CAEE almost abrogated adipogenesis (83.3?±?7.2% and 97.3?±?3.0% at 100?μM; IC₅₀ of 13.8 and 12.9?μM, respectively). The compounds inhibited adipogenic factors C/EBP-β and PPAR-γ and stimulated AMPK activity in the three cell-lines.

Discussion and conclusions: CAME and CAEE exerted antidiabetic activities in insulin-responsive cells through insulin-independent mechanisms involving AMPK and adipogenic factors.