Biological activities of the red algae Galaxaura rugosa and Liagora hawaiiana butters

The biological activities; antimicrobial, antioxidant and anticancer, of the red algae Galaxaura rugosa and Liagora hawaiiana were determined. The total ethanol, lipoidal matters, chloroform, n-butanol, aqueous extracts and powder of both algae showed and bacterial and antifungal activities. However, the chloroform extract of Galaxaura rugosa showed antibacterial activity against Klebsiella pneumoniae (24?mm, 0.15?mg/ml) higher than gentamycin (23?mm, 0.49?mg/ml). Moreover, the total ethanol, lipoidal matter and chloroform extracts showed antifungal activity (21, 22 and 25?mm, 1.25, 0.312 and 0.156?mg/ml) similar to the antibiotic Ketoconazole activity (23, 24 and 27?mm, 1.25, 0.312 and 0.156?mg/ml) against Aspergillus fumigatus, A. niger and Candida trobicalis, respectively. A good antioxidant activity (80.96%, IC₅₀?=?27.8?µg/ml) was provided by Galaxaura rugosa. The anticancer activity results revealed that the lipoidal matters of Galaxaura rugosa and Liagora hawaiiana possessed antitumor activity (IC₅₀?=?15?±?1.7 and 21.2?±?1.6, respectively) against lung carcinoma (A-549) better than vinblastine sulfate (IC₅₀?=?24.6?±?0.7). Although, the lipoidal matters of Galaxaura rugosa and Liagora hawaiiana antitumor activity against cervical carcinoma (HeLa) and intestinal carcinoma (CACO-2) (IC₅₀?=?10.2?±?0.6 and 12.2?±?0.6, respectively) preferable than vinblastine sulfate (IC₅₀?=?59.7?±?2.1 and 30.3?±?1.4, respectively).     

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.     

Bioactivity evaluation of cudraxanthone I,neocyclomorusin and (9βh)-3β-acetoxylanosta-7,24-diene isolated from <Emphasis Type="Italic">Milicia excelsa</Emphasis> Welw. C. C. Berg (Moraceae)

This study aimed to investigate the cytotoxic, antioxidant, and antimicrobial activities of three compounds isolated from the methanolic extract of the roots bark of Milicia excelsa (Moraceace) namely cudraxanthone I (1), neocyclomorusin (2) and (9βH)-3β-acetoxylanosta-7,24-diene (3). The cytotoxic activities of the compounds were determined using the xCELLigence system (Real Time Cell Analyzer). The compounds of cudraxanthone I and neocyclomorusin exhibited the excellent cytotoxic effects on the growth of human cervical epithelioid carcinoma (HeLa) cell lines (IC₅₀?<?10?µg/mL). Among the compounds; neocyclomorusin showed the highest radical scavenging activity (IC₅₀?=?0.73?±?0.01?mg/mL). The compounds exhibited low antimicrobial activity against Staphylococcus aureus ATCC 25923. This study supports the documented medicinal effects of the compounds and opens up the possibilities of pharmaceutical applications.     

Antioxidant,anticholinesterase and antibacterial activities of Stachys guyoniana and Mentha aquatica

Context: Stachys guyoniana Noë ex. Batt. and Mentha aquatica L. are two Algerian Lamiaceae used in folk medicine.

Objective: To investigate their antioxidant, anticholinesterase and antibacterial activities.

Material and methods: n-Butanol (BESG), ethyl acetate (EESG) and chloroform (CESG) extracts of S. guyoniana and methanol (MEMA) and chloroform (CEMA) aerial part extracts of M. aquatica and methanol (MERMA) and acetone (AERMA) roots extracts of M. aquatica were evaluated for their antioxidant activity by the β-carotene-linoleic acid, DPPH^? and ABTS^?+?scavenging, CUPRAC and metal chelating assays. The anticholinesterase activity was tested against AChE and BChE. The antibacterial activity was assessed by MICs determination against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella heidelberg, Klebsiella pneumoniae, Enterobacter aerogenes and Morganella morganii strains.

Results: In the β-carotene test, the CESG (IC₅₀: 2.3?±?1.27?μg/mL) exhibited the highest activity. The BESG was the best scavenger of DPPH^? (IC₅₀: 2.91?±?0.14?μg/mL). In the ABTS test, AERMA was the most active (IC₅₀: 4.21?±?0.28?μg/mL). However, with the CUPRAC, the BESG exhibited the best activity (A_0.50: 0.15?±?0.05?μg/mL) and was active in metal chelating assay with 48% inhibition at 100?μg/mL. The BESG was the best AChE inhibitor (IC₅₀: 5.78?±?0.01?μg/mL) however, the AERMA showed the highest BChE inhibitory activity (IC₅₀: 19.23?±?1.42?μg/mL). The tested extracts exhibited a good antibacterial activity.

Conclusion: This study demonstrated good antioxidant, anticholinesterase and antibacterial potential of S. guyoniana and M. aquatica, which fits in well with their use in folk medicine.     

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.     

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.     

Investigation of nepetolide as a novel lead compound: Antioxidant,antimicrobial, cytotoxic,anticancer, anti-inflammatory,analgesic activities and molecular docking evaluation

In the present study, we describe various pharmacological effects and computational analysis of nepetolide, a tricyclic clerodane-type diterpene, isolated from Nepeta suavis. Nepetolide concentration-dependently (1.0–1000?µg/mL) exhibited 1,1-diphenyl,2-picrylhydrazyl free radical scavenging activity with maximum effect of 87.01?±?1.85%, indicating its antioxidant potential, as shown by standard drug, ascorbic acid. It was moderately active against bacterial strain of Staphylococcus aureus. In brine shrimp’s lethality model, nepetolide potently showed cytotoxic effect, with LC₅₀ value of 8.7?µg/mL. When evaluated for antitumor activity in potato disc tumor assay, nepetolide exerted tumor inhibitory effect of 56.5?±?1.5% at maximum tested concentration of 1000?µg/mL. Nepetolide at 20?mg/kg reduced carrageenan-induced inflammation (P?<?.001 vs. saline group) in rat paw. Nepetolide dose-dependently (100–500?mg/kg) decreased acetic acid evoked writhes, as exhibited by diclofenac sodium. In-silico investigation of nepetolide was carried out against cyclooxygenase-2, epidermal growth factor receptor and lipoxygenase-2 targets. Virtual screening through Patchdock online docking server identified primarily hydrophobic interactions between ligand nepetolide and receptors proteins. Enhanced hydrogen bonding was predicted with Autodock showing 6–8 hydrogen bonds per target. These results indicate that nepetolide exhibits antioxidant, antibacterial, cytotoxic, anticancer, anti-inflammatory and analgesic activities and should be considered as a lead compound for developing drugs for the remedy of oxidative stress-induced disorders, microbial infections, cancers, inflammations and pain.     

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.     

Antioxidant and antimicrobial activities of branches extracts of five Juniperus species from Turkey

Context: Several Juniperus species (Cupressaceae) are utilized in folk medicine in the treatment of infections and skin diseases.

Objective: This work was designed to evaluate the antioxidant and antimicrobial potential of methanol and water branches extracts of Juniperus species from Turkey: Juniperus communis L. var. communis (Jcc), Juniperus communis L. var. saxatilis Pall. (Jcs), Juniperus drupacea Labill. (Jd), Juniperus oxycedrus L. subsp. oxycedrus (Joo), Juniperus oxycedrus L. subsp. macrocarpa (Sibth. & Sm.) Ball. (Jom).

Materials and methods: Total phenolics, total flavonoids and condensed tannins were spectrophotometrically determined. The antioxidant properties were examined using different in vitro systems. The toxicity was assayed by Artemia salina lethality test. The antimicrobial potential against bacteria and yeasts was evaluated using minimum inhibitory concentration and minimum bactericidal concentration (MIC/MBC) measurements. The effect on bacteria biofilms was tested by microtiter plate assay.

Results: Both in the DPPH (1,1-diphenyl-2-picrylhydrazyl) and TBA (thiobarbituric acid) test Jom resulted the most active (IC₅₀?=?0.034?±?0.002?mg/mL and 0.287?±?0.166 µg/mL). Joo exhibited the highest reducing power (1.78?±?0.04 ASE/mL) and Fe²⁺ chelating activity (IC₅₀?=?0.537?±?0.006?mg/mL). A positive correlation between primary antioxidant activity and phenolic content was found. The extracts were potentially non-toxic against Artemia salina. They showed the best antimicrobial (MIC?=?4.88-30.10 µg/mL) and anti-biofilm activity (60–84%) against S. aureus.

Discussion and conclusion: The results give a scientific basis to the traditional utilization of these Juniperus species, also demonstrating their potential as sources of natural antioxidant and antimicrobial compounds.     

Volatile composition and antimicrobial activity of the essential oil of Artemisia absinthium growing in Western Ghats region of North West Karnataka,India

Abstract

Context: Artemisia absinthium L. (Asteraceae) is an aromatic, herbaceous, perennial plant commonly known as wormwood. Artemisia absinthium is traditionally used as an anthelmintic, antiseptic, antispasmodic and for bacillary dysentery, cancers and neurodegenerative diseases.

Objective: The essential oil composition of the leaves of A. absinthium growing in the Western Ghats region of North West Karnataka, India, is investigated for the first time in this region and the oil was screened for antimicrobial properties.

Materials and methods: The chemical composition of the hydro-distilled essential oil obtained from the leaves of A. absinthium was analyzed by GC-FID and GC/MS. The oil was tested against five Gram positive and, eight Gram negative bacteria and three fungi by the tube-dilution method at a concentration range of 5000–9?µg/mL.

Results: Results demonstrated that the leave oil was found to be rich in oxygenated monoterpenes (39.7% and 41.1%). The major compounds were borneol (18.7% and16.7%), methyl hinokiate (11.9% and 12.9%), isobornyl acetate (4.0% and 4.7%), β-gurjunene (3.8% and 4.4%) and caryophyllene oxide (3.7% and 4.3%), among 64 identified compounds, comprising 91.7% and 90.1% of the total oil. The organism Micrococcus luteus was found more susceptible to the oil with an MIC value of 25?±?4?µg/mL, followed by Micrococcus flavus, Bacillus subtilis, Penicillium chrysogenum and Aspergillus fumigatus with MIC values of 58?±?8, 65?±?8, 84?±?15 and 91?±?13?µg/mL, respectively.

Discussion and conclusion: The oil showing antimicrobial activity against bacteria and fungi validate the traditional use of the plant as an antiseptic.     

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

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

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

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

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

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

Antimicrobial,antioxidant and anticancer activities of Laurencia catarinensis,Laurencia majuscula and Padina pavonica extracts

The antimicrobial, antioxidant, and anticancer activities of ethanolic extract of Laurencia catarinensis, L. majuscula and Padina pavonica were determined. The highest antibacterial activity; 23.40?±?0.58?mm (00.98?µg/ml) and 22.60?±?2.10?mm (03.90?µg/ml) were obtained against Klebsiella pneumonia by Laurencia catarinensis and Padina pavonica, respectively. However, Padina pavonica showed excellent antibacterial activity against Bacillus subtilis (21.7?±?1.5?mm; 1.95?µg/ml), Staphylococcus aureus (21.7?±?0.58?mm; 1.95?µg/ml), Streptococcus pyogenes (20.7?±?1.2?mm; 1.95?µg/ml) and Acinetobacter baumannii (20.1?±?1.2?mm; 3.9?µg/ml). Moreover, the highest antifungal activity; 24.7?±?2.0?mm (0.98?µg/ml), 23.7?±?1.5?mm (0.98?µg/ml), 23.6?±?1.5?mm (0.98?µg/ml) was obtained by Padina pavonica against Candida tropicalis, C. albicans and Aspergillus fumigatus, respectively. The algal extracts showed DPPH radical scavenging activity in a concentration–dependent manner with maximum scavenging activity (77.6%, IC₅₀?=?5.59?µg/ml and 77.07%, IC₅₀?=?14.3?µg/ml) was provided by Padina pavonica and Laurenica majuscula, respectively. The in vitro antitumor activity revealed that the IC₅₀ values of Padina pavonica were 58.9, 115.0, 54.5, 59.0, 101.0, 101.0, and 97.6?µg/ml; Laurencia catarinensis were 55.2, 96.8, 104.0, 78.7, 117.0, 217.0, 169.0?µg/ml; and Laurencia. majuscula were 115.0, 221.0, 225.0, 200.0, 338.0, 242.0, and 189.0?µg/ml; respectively against A-549 (Lung carcinoma), Caco-2 (Intestinal carcinoma), HCT-116 (Colon carcinoma), Hela (Cervical carcinoma), HEp-2 (Larynx carcinoma), HepG-2 (Hepatocellular carcinoma), and MCF-7 (Breast carcinoma) cell lines.     

Flavonoids in Scutellaria immaculata and S. ramosissima (Lamiaceae) and their biological activity

Objectives The aim of this study was to investigate the flavonoid composition of Scutellaria immaculata and S. ramosissima (Lamiaceae) and the in‐vitro biological activity of their extracts and flavonoids. Methods The flavonoid composition of S. immaculata (Si) and S. ramosissima (Sr) were analysed using LC‐MS. Antimicrobial activity was studied in vitro against a range of bacteria and fungi using diffusion and microdilution methods. Anti‐trypanosomal and cell proliferation inhibitory activity of the extracts and flavonoids was assessed using MTT. The antioxidant activity of the flavonoids and extracts were evaluated using DPPH* test. Key findings LC‐MS investigation of Si and Sr plants allowed the identification, for the first time, of an additional 9 and 16 flavonoids, respectively. The methanol, chloroform and water extracts from these plants and six flavonoids (scutellarin, chrysin, apigenin, apigenin‐7‐O‐glucoside, cynaroside and pinocembrine) exhibited significant inhibition of cell growth against HeLa, HepG‐2 and MCF‐7 cells. The chloroform extract of Sr showed potent cytotoxic effects with IC50 (drug concentration which resulted in a 50% reduction in cell viability) values of 9.25 ± 1.07 µg/ml, 12.83 ± 1.49 µg/ml and 17.29 ± 1.27 µg/ml, respectively. The highest anti‐trypanosomal effect against T. b. brucei was shown by the chloroform extract of Sr with an IC50 (drug concentration which resulted in a 50% inhibition of the biological activity) of 61 µg/ml. The pure flavonoids showed an IC50 range between 3 and 29 µm , with cynaroside as the most active compound with an IC50 value of 3.961 ± 0.133 µm . The chloroform extract of Sr has potent antimicrobial activity against Streptococcus pyogenes (minimum inhibitory concentration, MIC = 0.03 mg/ml). Pinocembrine exhibited a strong activity against the all bacteria except Escherichia coli and yeasts. Water extracts of Sr and Si exhibited potent antioxidant activity with IC50 values of 5.62 ± 0.51 µg/ml and 3.48 ± 0.02 µg/ml, respectively. Scutellarin exerted stronger antioxidant activity than other flavonoids. Conclusions This is the first study reporting an in‐vitro biological investigation for Si and Sr. Especially the chloroform extract of Sr showed potent anticancer and antimicrobial activity. Cynaroside had a highly selective and strong cytotoxicity against T. b. brucei while showing only mild effects against cancer cells.     

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.     

Phytochemical standardization and biological activities of certain desert plants growing in Saudi Arabia

The phytochemical screening, antimicrobial and antitumor activities of Calendula tripterocarpa, Centarea sinaica, Centaurea pseudosinaica, Koelpinia linearis, Plectranthus arabicus, Plectranthus asirensis and Tripleurospermum auriculatum determined. The best antibacterial activity; 41.8?±?0.23?mm, 39.7?±?0.25?mm, 35.8?±?0.58?mm, 34.7?±?0.51?mm and 32.7?±?0.25?mm was obtained by Plectranthus arabicus against Klebsiella pneumonia, Tripleurospermum auriculatum against Bacillus subtilis, Centaurea pseudosinaica against Bacillus subtilis, Centaurea pseudosinaica against Stroptococcus pyogenes and Plectranthus arabicus against Staphylococcus epidermidis, respectively. While the highest antifungal activity; 35.9?±?1.15?mm, 34.6?±?0.34, 30.6?±?0.26?mm and 29.9?±?0.63?mm was obtained by Tripleurospermum auriculatum against Geotricum candidum, Candida albicans, C. tropicalis and Aspergillus fumigatus, respectively. The antitumor activity (IC₅₀) obtained by Centarea sinaica; 3.1?±?6.9?µg/ml, 14.3?±?3.1?µg/ml and 22.7?±?4.1?µg/ml was better than activity of vinblastine sulphate; 5.9?±?0.4?µg/ml, 59.7?±?2.1?µg/ml and 30.3?±?1.4?µg/ml against breast carcinoma (MCF-7), cervical carcinoma (Hela) and colorectal carcinoma (CACO), respectively. Plectranthus arabicus alcoholic extract showed higher antitumor activity; 15.3?±?5.3?µg/ml, 28.6?±?3.6?µg/ml and 24.3?±?4.1?µg/ml than vinblastine; 21.2?±?0.9?µg/ml, 59.7?±?2.1?µg/ml and 30.3?±?1.4?µg/ml against prostate carcinoma (Pc3), cervical carcinoma (Hela) and colorectal carcinoma (CACO), respectively. Also, the antitumor activity of Plectranthus asirensis against cervical carcinoma (Hela) (37.1?±?2.6?µg/ml) was potent than vinblastine sulphate (59.7?±?2.1?µg/ml). The obtained results of LD₅₀ and sub-chronic toxicity revealed that the plants have no toxicity.     

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.     

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 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.     

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.     

Chemical profiling of <Emphasis Type="Italic">Phlomis thapsoides</Emphasis> (Lamiaceae) and in vitro testing of its biological activities

A phytochemical study of Phlomis thapsoides (Lamiaceae) resulted in the isolation of one new compound, 6,10,17-trimethyl-2-octadecanone, and three known compounds (sitosterol-3-O-β-glucoside, and the iridoid glucosides ipolamiide and lamiide). The structures of the isolated compounds were elucidated using mass spectrometry, 1D/2D NMR spectroscopy experiments in comparison with published data. The chemical composition of the essential oil obtained from aerial parts of P. thapsoides was determined by gas liquid chromatography and gas liquid chromatography-mass spectroscopy. The main volatile constituents were phenylethyl alcohol (6.81?%), trans-3-hexenol (5.55?%), 1-octen-3-ol (5.10?%), α-cadinol (4.92?%), and α-muurolol (4.67?%). The antioxidant activity of the extracts was evaluated by three methods: 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity, 2,2′-azinobis-[3-ethylbenzthiazoline-6-sulfonic acid] and ferric reducing antioxidant power assay along with the determination of total phenolic content. Although the ethyl acetate extract contained 362.06?mg of gallic acid equivalents, the antioxidant activities, as revealed by 1,1-diphenyl-2-picrylhydrazyl, 2,2′-azinobis-[3-ethylbenzthiazoline-6-sulfonic acid] and ferric reducing antioxidant power assays, were of medium strength (IC₅₀ of 73.08?±?3.18, 9.48?±?0.71?µg/mL and 9.33?±?0.17?mM of FeSO₄ equivalents, respectively). Only lamiide inhibited soybean 5-lipoxygenase with an IC₅₀ value of 72.92?µg/mL in vitro. In-silico molecular modeling studies on 5-lipoxygenase and human 5-lipoxygenase-activating protein were used to evaluate the potential anti-inflammatory activity. Sitosterol-3-O-β-glucoside followed by the iridoid glucoside lamiide exhibited the highest inhibition of 5-lipoxygenase whereas the new compound 6,10,17-trimethyl-2-octadecanone and sitosterol-3-O-β-glucoside exhibited the highest inhibition of 5-lipoxygenase-activating protein as evidenced from their higher fitting scores. The cytotoxicity of the plant extracts and lamiide against Caco2 and HepG-2 cancer cells resulted in IC₅₀ values of >100?µg/mL indicating a low cytotoxicity.