Antioxidant, antimicrobial and antiproliferative activities of Anthemis palestina essential oil.

BACKGROUND: Anthemis palestina (Asteraceae) extends across the Mediterranean region, southwest Asia and eastern Africa. Although traditionally used for several applications, in vitro investigation of biological functions associated with Anthemis palestina essential oil had never been reported. METHODS: The air-dried flowers of Anthemis palestina were subjected to hydrodistillation to yield the oil. The antioxidant activity of the hydrodistilled oil was characterized using various in vitro model systems such as DPPH, ferric-reducing antioxidant power and hydroxyl radical scavenging activity. Antibacterial activity was tested against six bacterial species, representing both Gram positive and Gram negative bacteria. Antifungal activity was evaluated using three Candida species. The minimum inhibitory concentration (MIC) for each examined microorganism was determined using the microdilution method. The oil's antiproliferative effects against eight human cancer cell lines were also studied and the lethal doses that resulted in 50% reduction of cell viability (LD50) were determined. RESULTS: The results indicate that the essential oil of Anthemis palestina exhibited substantial antioxidant activities as demonstrated with DPPH, ferric reducing antioxidant power, and hydroxyl radical scavenging activity. In addition, a broad-spectrum antibacterial activity of the oil was revealed with better susceptibility of Gram positive bacteria towards the oil. The MIC values ranged between 6-75 µg/ml. Besides, the oil demonstrated a moderate inhibitory effect on the three Candida species examined; with MIC values ranging between 48-95 µg/ml. Potent cytotoxic activities, especially against HeLa cell line; with LD50 of 32 µg/ml, BJAB cell line; with LD50 of 57 µg/ml, and Caco-2 cell line; with LD50 of 61 µg/ml, were observed. CONCLUSION: The results obtained indicate high potential of Anthemis palestina essential oil as bioactive oil, for nutraceutical and medical applications, possessing antioxidant, antimicrobial and antiproliferative activities.

Liquid chromatography-mass spectroscopy and liquid chromatography-ultraviolet/visible photodiode array analysis of selected colchicum species.

An in-house strategy to dereplicate colchicinoid alkaloids was recently developed by our team. It aimed at quickly identifying Colchicum constituents using LC-MS (liquid chromatography-mass spectroscopy) and LC-UV/Vis PDA (liquid chromatography-ultraviolet/ visible photodiode array) techniques. In this project, our goal was to validate the developed method through analysing the alkaloid-rich fractions of three Colchicum species that had been previously studied phytochemically using the traditional bioactivity-guided fractionation methodology. The analysed species were Colchicum tauri Siehe ex Stefanoff, Colchicum stevenii Kunth, and Colchicum tunicatum Feinbr., all belonging to the family Colchicaceae. In addition to identifying the compounds previously isolated and characterized by the traditional methodology, the new strategy succeeded in tentatively identifying a set of known compounds, but new to the species.

UPLC-HRESI-MS and GC-MS analysis of the leaves of Nicotiana glauca.

The alkaloid-rich fraction obtained by fractionation of the crude methanolic extract of the leaves of wild tobacco tree Nicotiana glauca Graham (Solanaceae) was analyzed using UPLC-MS and GC-MS. Anabasine, a piperidine alkaloid, was identified as the major constituent with approximately 60 % (m/m) of the alkaloid-rich fraction. In addition to anabasine, six secondary metabolites were identified using high-resolution UPLC-MS. Anabasine was quantified in the leaves to be 1 mg g-1 dry plant material. The GC-MS analysis revealed five compounds with anabasine as the major component, while nicotine was not detected. Moreover, GC-MS was used for the analysis of the volatile oil that was obtained by hydro-distillation from the leaves of N. glauca. The volatile plant oil was found to be rich in oxygenated sesquiterpenes (e.g., ß-bisabolol) and carboxylic acids and esters (e.g., ethyl linoleate and hexadecanoic acid), whereas anabasine was not detected.

Pancreatic lipase inhibition activity of trilactone terpenes of Ginkgo biloba.

The prevalence of obesity is increasing at an alarming rate, but, unfortunately, only a few drugs are currently available on the market. In the present study, the methanolic extract of Ginkgo biloba L. (Ginkgoaceae) was investigated as an inhibitor of pancreatic lipase (PL) in an attempt to explain its hypolipidaemic activity. In vitro assay of G. biloba leaves extract revealed a substantial PL inhibition activity (IC(50) = 16.5 µg/mL). Further investigation was performed by employing theoretical docking simulations and experimental testing to uncover the active constituents responsible for G. biloba anti-lipase activity. Virtually, terpene trilactones, including ginkgolides and bilobalide, were found to fit within the binding pocket of PL via several attractive interactions with key amino acids. Experimentally, ginkgolides A, B, and bilobalide were found to inhibit PL significantly (IC(50) = 22.9, 90.0, and 60.1 µg/mL, respectively). Our findings demonstrated that the hypolipidaemic effects of G. biloba extract can be attributed to the inhibition of PL by, at least in part, terpene trilactones. In conclusion, this work can be considered a new step towards the discovery of new natural safe hypolipidaemic PL inhibitors.

A bioactive prodelphinidin from Mangifera indica leaf extract.

A new trimeric proanthocyanidin, epigallocatechin-3-O-gallat-(4beta-->8)-epigallocatechin-(4beta-->8)-catechin (1), was isolated together with three known flavan-3-ols, catechin (2), epicatechin (3), and epigallocatechin (4), and three dimeric proanthocyanidins, 5-7, from the air-dried leaves of Mangifera indica. Their chemical structures were determined on the basis of 1D- and 2D-NMR spectra (HSQC, HMBC) of their peracetylated derivatives, MALDI-TOF-mass spectra, and by acid-catalyzed degradation with phloroglucinol. The isolated compounds 1-7 were in vitro tested for their inhibitory activities against COX-1 and COX-2. Compound 1 was found to have a potent inhibitory effect on COX-2, while compounds 1 and 5-7 exhibited moderate inhibition against COX-1.

Antioxidant, antihyperuricemic and xanthine oxidase inhibitory activities of Hyoscyamus reticulatus.

CONTEXT: Xanthine oxidase (XO) is a key enzyme in the pathophysiological homeostasis of hyperuricemia. It catalyzes the oxidation of hypoxanthine to xanthine and then to uric acid, the reaction involves the formation of free radical intermediates and superoxide byproducts. OBJECTIVES: This study was undertaken to investigate the antioxidant, antihyperuricemic, and xanthine oxidase inhibitory potentials of Hyoscyamus reticulatus L. (Solanaceae) extract. MATERIALS AND METHODS: The antioxidant potency was measured using the ABTS•+ scavenging capacity system, which includes Trolox as a standard. The xanthine oxidase inhibitory activity of the extract was quantitated in vitro by measuring the decline in the catalytic rate of xanthine oxidase following incubations with the plant extracts and using xanthine as a substrate. The hypouricemic potential of the extract was evaluated using an in vivo model for hyperuricemia. We tested three different doses of the extract and allopurinol was used as standard antihyperuricemic positive control. RESULTS: H. reticulatus aqueous extract exhibited significant antioxidant scavenging properties (533.26 µmol TE/g dry extract weight) and inhibitory effect on xanthine oxidase activity (IC50 12.8 µg/mL). Furthermore, oral administration of the aqueous extract significantly reduced serum urate levels in oxonate-induced hyperuricemic mice in a dose-dependent manner. DISCUSSION AND CONCLUSION: Our results suggest that the aqueous extract of H. reticulatus aerial parts might have great potential as an antioxidant and a hypouricemic agent. Our lab is currently identifying the active compounds in the extract to which the biological activities could be attributed.

Proliferation of antibiotic-producing bacteria and concomitant antibiotic production as the basis for the antibiotic activity of Jordan's red soils.

Anecdotes, both historical and recent, recount the curing of skin infections, including diaper rash, by using red soils from the Hashemite Kingdom of Jordan. Following inoculation of red soils isolated from geographically separate areas of Jordan, Micrococcus luteus and Staphylococcus aureus were rapidly killed. Over the 3-week incubation period, the number of specific types of antibiotic-producing bacteria increased, and high antimicrobial activity (MIC, approximately 10 microg/ml) was observed in methanol extracts of the inoculated red soils. Antibiotic-producing microorganisms whose numbers increased during incubation included actinomycetes, Lysobacter spp., and Bacillus spp. The actinomycetes produced actinomycin C(2) and actinomycin C(3). No myxobacteria or lytic bacteriophages with activity against either M. luteus or S. aureus were detected in either soil before or after inoculation and incubation. Although protozoa and amoebae were detected in the soils, the numbers were low and did not increase over the incubation period. These results suggest that the antibiotic activity of Jordan's red soils is due to the proliferation of antibiotic-producing bacteria.

LC-MS and LC-PDA analysis of Hypericum empetrifolium and Hypericum sinaicum.

Within the framework of our continuous efforts to explore Hypericum species from Jordan, we report the analysis of the major active metabolites, naphthodianthrones and phloroglucinols, in the methanolic extracts of two under-explored Hypericum species; H. empetrifolium Willd. and H. sinaicum Hochst. & Steud. ex Boiss., using LC-(+,-)-ESI-MS (TIC and SIM) and LC-UV/Vis spectroscopy. Based on their LC-UV/Vis profiles, retention times and (+,-)-ESI-MS (TIC and SIM) spectral data, hypericin, protohypericin and pseudohypericin were identified in both of the investigated species. In addition adhyperfirin was only detected in H. empetrifolium, while hyperforin and protopseudohypericin were only detected in H. sinaicum. This is the first report documenting the presence of hypericin, protohypericin, pseudohypericin, protopseudohypericin, and hyperforin in H. sinaicum, and adhyperfirin in H. empetrifolium.

Dereplication of bioactive constituents of the genus hypericum using LC-(+,-)-ESI-MS and LC-PDA techniques: Hypericum triquterifolium as a case study.

Utilizing liquid chromatography-electro spray ionization-mass spectrometry (LC-(+,-)-ESI-MS) and liquid chromatography-photodiode array detection (LC-PDA) techniques, a dereplication strategy for the analysis of the secondary metabolites constituents of the genus Hypericum has been developed. From the crude methanolic extract of the aerial parts of H. triquetrifolium (leaves, stems, and flowers) and on the basis of their UV-profiles, chromatographic retention times and (+,-)-ESI-MS (TIC and SIM) mass spectral data, seven known (1-7) compounds were dereplicated fairly rapidly. The compounds were classified into three structural classes: phloroglucinols: hyperfirin and adhyperfirin; naphthodianthrones: hypericin, pseudo-hypericin, proto-hypericin, and protopseudo-hypericin; and the flavonoid rutin.

Pyrrolizidine alkaloids from Echium glomeratum (Boraginaceae).

The methanolic extract of the whole plant of Echium glomeratum Poir. (Boraginaceae) has afforded five pyrrolizidine alkaloids, three that were (7S, 8R)-petranine (1), (7S, 8S)-petranine (2), and (7R, 8R)-petranine (3a) or (7R, 8S)-petranine (3b), comprising a tricyclic pyrrolizidine alkaloids subclass; and two that were known but to the species: 7-angeloylretronecine (4) and 9-angeloylretronecine (5). All compounds were tested against a human tumor panel for cytotoxicity; no activity was observed (EC50 values>20microg/ml).

Colchicinoids from Colchicum crocifolium Boiss.: a case study in dereplication strategies for (-)-colchicine and related analogues using LC-MS and LC-PDA techniques.

As a part of a project designed to investigate Colchicum species in Jordan, the chemical constituents of Colchicum crocifolium Boiss. (Colchicaceae) were investigated using LC-MS and LC-UV/Vis PDA. A decision tree for working with colchicinods has been developed by incorporating data from LC-UV/PDA and LC-MS. This dereplication strategy draws upon the UV/PDA spectra to classify compounds into one of four structural groups and combines this with retention time and mass spectra/molecular weight to identify the compounds. This strategy was applied on a small amount of extract (2 mg) of Colchicum crocifolium to dereplicate 10 known compounds from four different structural groups, namely (-)-demecolcine, 2-demethyl-(-)-colchicine or 3-demethyl-(-)-colchicine, N-deacetyl-(-)-colchicine, (-)-colchiciline, (-)-colchicine, beta-lumidemecolcine, 2-demethyl-beta-lumicolchicine or 3-demethyl-beta-lumicolchicine, N,N-dimethyl-N-deacetyl-beta-lumicornigerine, (-)-isoandrocymbine and (-)-autumnaline. Furthermore, a new compound was identi?ed as N,N-dimethyl-N-deacetyl-(-)-cornigerine. Three compounds, which had molecular ions at m/z 325, 340 and 374, could not be dereplicated into any obvious structural classes that have been isolated in our laboratories previously or reported in the literature.

Antioxidant activity and total phenolic content of aqueous and methanolic extracts of Jordanian plants: an ICBG project.

As part of an International Cooperative Biodiversity Groups (ICBG) program to study Jordan's biodiversity, the relative levels of antioxidant activity and the total phenolic content of aqueous and methanolic extracts of a total of 95 plant species, all of Jordanian origin and those collected at random, have been measured. The total phenolic content of aqueous and methanolic extracts of the investigated plant species ranged from 4.4 to 78.3 mg and from 2.1 to 52.8 mg gallic acid equivalents g(-1) dry weight, respectively, while the total antioxidant capacity ranged from 20.0 to 916.7 and from 15.1 to 915.6 micromol Trolox equivalents g(-1) dry weight, respectively. Based on this collection, approximately 5% of assayed plants showed high levels of antioxidant activity. There was a significant linear correlation between antioxidant activity and total phenolic content for aqueous and methanolic extracts, suggesting that phenolic compounds were the predominant antioxidant components in the investigated plant species. Interestingly, a few of the collected plants had high-antioxidant activity yet "low" phenolic content includes Ceratonia siliqua and Viscum cruciatum. These plants may serve as sources of antioxidants with new chemotypes.

Phytochemical and biological investigation of Aristolochia maurorum L.

Aristolochia maurorum L. of Jordanian origin has been investigated phytochemically, quantitatively, and biologically. Three atypical alkaloids, namely aristolochic acid I (1), aristolochic acid II (2) and aristolochic acid IIIa (3), have been isolated and identified. Of these known 1-phenanthrenecarboxylic acids, 2 and 3 are reported for the first time from this species. The identified compounds 1-3 were first evaluated biologically as cytotoxic agents against the brine shrimp lethality test (BST), in which compound 1 was found to be the most potent (LC50, 4.9 microg/mL). The antiplatelet activity of the methanolic extracts, the acidic fractions of aerial and root parts, and the identified compounds 1-3 were evaluated using an automatic platelet aggregometer and coagulation tracer (APACT 2). Using external reference standards, and a reverse-phase isocratic method, the distribution of aristolochic acid I and aristolochic acid II in different plant parts of Aristolochia maurorum L. during flowering stage was analyzed by PDA-HPLC. A quantitative comparison between two previously reported extraction methods was also made. Roots were found to be the main storage of aristolochic acid I and aristolochic acid II during flowering stage with about 0.22 and 0.108% (w/w), respectively.

Phytochemical study and cytotoxicity evaluation of Colchicum stevenii Kunth (Colchicaceae): a Jordanian meadow saffron.

Isolation, characterization, and biological evaluation of active components of Colchicum stevenii Kunth (Colchicaceae) are described. Colchicum stevenii is an unexplored Jordanian specie with toxic reputation. Directed by brine shrimp lethality test (BST), methanolic extraction, liquid-liquid partition, preparative TLC, and semi-preparative HPLC, it resulted in the isolation of six cytotoxic compounds. The compounds, reported for the first time from this specie, are: (-)-colchicine (1), 2-demethyl-(-)-colchicine (2), (-)-cornigerine (3), beta-lumicolchicine (4), (-)-isoandrocymbine (5) and (-)-O-methylandrocymbine (6). A new, in-house developed, acidic-based reverse-phase gradient semi-preparative HPLC method for the separation of colchisides is presented here. Structural elucidation was based on spectroscopic techniques principally; 1H-NMR and low resolution EIMS. Based on BST results, reported as LC50 values in microg mL(-1) (ppm) with 95% confidence intervals, (-)-colchicine (2.5 ppm) and (-)-cornigerine (2.7 ppm) were the most potent.

Seasonal variation of colchicine content in Colchicum brachyphyllum and Colchicum tunicatum (Colchicaceae).

As part of our continuing investigation of Jordanian Colchicum species, (-)-colchicine content in C. brachyphyllum Boiss. & Haussk. ex Boiss and Colchicum tunicatum Feinbr (Colchicaceae), growing wild in Jordan, was determined during different growth stages. Using external reference standard, a reverse-phase gradient photo-diode array high performance liquid chromatography (PDA-HPLC) method was adapted. Underground parts in both species and during different growth stages, always showed higher (-)-colchicine content than the above ground parts. In C. brachyphyllum total (-)-colchicine content of underground parts during flowering stage was found to be about 0.15% (wt/wt), while that of aerial parts was only about 0.04% (wt/wt). In C. tunicatum total (-)-colchicine content of underground parts was found to be 0.12% (wt/wt), and 0.13% (wt/wt) during flowering and vegetating stages, respectively, while that of aerial parts was only about 0.04% (wt/wt) and 0.02% (wt/wt), respectively. In C. tunicatum, stems, roots and unripe seeds are the main storages of (-)-colchicine at flowering, vegetating and seeding stages, respectively, while in C. brachyphyllum, corms are the main storage of (-)-colchicine at flowering and seeding stages.

Phytochemical studies and cytotoxicity evaluations of Colchicum tunicatum Feinbr and Colchicum hierosolymitanum Feinbr (Colchicaceae): two native Jordanian meadow saffrons.

As a part of our continuing investigation of Jordanian Colchicum species, the biologically active components of Colchicum hierosolymitanum Feinbr and Colchicum tunicatum Feinbr (Colchicaceae) were pursued. The brine shrimp lethality test (BSLT) was used to direct the fractionation and isolation of active components. Five and four known colchicinoids were isolated and characterized from C. tunicatum and C. hierosolymitanum, respectively. The known colchicinoids, reported for the first time from these two species are: (-)-colchicine (I), 3-demethyl-(-)-colchicine (II), (-)-cornigerine (III), beta-lumicolchicine (IV), and (-)-androbiphenyline (V) from C. tunicatum, and (-)-colchicine (I), 2-demethyl-(-)-colchicine (VI), (-)-cornigerine (III), and beta-lumicolchicine (IV) from C. hierosolymitanum. The chemical structures of the isolated compounds have been elucidated using a series of spectroscopic and spectrometric techniques principally; 1D-NMR (1H and 13C) and low resolution EI-MS and APCIMS. All pure compounds were evaluated for cytotoxicity against three human cancer cell lines; MCF-7 human breast carcinoma, NCI-H460 human large cell lung carcinoma, and SF-268 human astrocytoma. (-)-Colchicine (I) and (-)-cornigerine (III) were found to be the most bioactive of the identified compounds with EC50 values in the range of 0.016-0.097 microM.

Studies on the In Vitro Antiproliferative, Antimicrobial, Antioxidant, and Acetylcholinesterase Inhibition Activities Associated with Chrysanthemum coronarium Essential Oil.

The essential oil of the Jordanian Chrysanthemum coronarium L. (garland) was isolated by hydrodistillation from dried flowerheads material. The oil was essayed for its in vitro scavenging activity using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. The results demonstrate that the oil exhibits moderate radical scavenging activity relative to the strong antioxidant ascorbic acid. In addition, cholinesterase inhibitory activity of C. coronarium essential oil was evaluated for the first time. Applying Ellman's colorimetric method, interesting cholinesterase inhibitory activity, which is not dose dependent, was evident for the oil. Furthermore, antimicrobial activities of the oil against both Gram-negative and Gram-positive bacteria were evaluated. While it fails to inhibit Gram-negative bacteria growth, the antibacterial effects demonstrated by the oil were more pronounced against the Gram-positive strains. Moreover, the examined oil was assessed for its in vitro antiproliferative properties where it demonstrated variable activities towards different human cancer cell lines, of which the colon cancer was the most sensitive to the oil treatment.

Determination of hypericin content in Hypericum triquetrifolium Turra (Hypericaceae) growing wild in Jordan.

Hypericin content of methanolic extracts of dried flowers, leaves, stems, and roots of Hypericum triquetrifolium (Turra) were determined by HPLC. Conversion of protohypericin to hypericin was achieved by exposing samples to light for 30 min immediately before HPLC analysis. External standard calibration was used to quantify hypericin. Leaves showed the highest hypericin content of 0.36% w/w. Total aerial parts contained 0.43% w/w of hypericin. The relatively high hypericin content of the H. triquetrifolium in this study encourages the introduction, cultivation, and biological evaluation of hypericum specie in Jordan.

Xanthine oxidase inhibitory activity of the methanolic extracts of selected Jordanian medicinal plants.

BACKGROUND: The search for novel xanthine oxidase (XO) inhibitors with a higher therapeutic activity and fewer side effects are desired not only to treat gout but also to combat various other diseases associated with the XO activity. At present, the potential of developing successful natural products for the management of XO-related diseases is still largely unexplored. In the present study, we have screened the methanolic extracts of various Jordanian medicinal plants for their XO inhibitory activities using an optimized protocol. MATERIALS AND METHODS: The methanolic extracts of 23 medicinal plants, belonging to 12 families, were tested in vitro, at 200 µg/ml concentrations, for their XO inhibitory potential. The dose-dependent inhibition profiles of the most active plants were further evaluated by estimating the IC(50) values of their corresponding extracts. RESULTS: Six plants were found most active (% inhibition more than 39%). These plants are Salvia spinosa L. (IC(50) = 53.7 µg/ml), Anthemis palestina Boiss. (168.0 µg/ml), Chrysanthemum coronarium L. (199.5 µg/ml), Achillea biebersteinii Afansiev (360.0 µg/ml), Rosmarinus officinalis L. (650.0 µg/ml), and Ginkgo biloba L. (595.8 µg/ml). Moreover, four more plants, namely Lavandula angustifolia Mill. (28.7% inhibition), Helianthemum ledifolium (L.) Mill. (28.4%), Majorana syriaca (L.) Kostel. (25.1%), and Mentha spicata L. (22.5%) showed a XO inhibitory activity in the range of 22-30%. CONCLUSION: The study showed that many of the tested plant species are potential sources of natural XO inhibitors that can be developed, upon further investigation, into successful herbal drugs for treatment of gout and other XO-related disorders.

Colchicinoids from Colchicum crocifolium Boiss. (Colchicaceae).

A new colchicinoid from Colchicum crocifolium Boiss. (Colchicaceae) was isolated and identified as N,N-dimethyl-N-deacetyl-(-)-cornigerine (5), along with four known compounds, but new to the species: (-)-colchicine (1), (-)-demecolcine (2), (-)-N-methyl-(-)-demecolcine (3) and 3-demethyl-N-methyl-(-)-demecolcine (4). All isolated compounds showed potent cytotoxicity against a human cancer cell panel.