23 results on '"Ismail, F"'
Search Results
2. Chemodiversity and Antiproliferative Activity of the Essential Oil of Schinus molle Growing in Jordan
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Oriana Awwad, Fatma U. Afifi, Reem Abbassi, Enam A. Khalil, Nour H. Aboalhaija, and Ismail F. Abaza
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Cell Survival ,Anacardiaceae ,Bioengineering ,Biochemistry ,law.invention ,Schinus molle ,chemistry.chemical_compound ,law ,Oils, Volatile ,Tumor Cells, Cultured ,Humans ,Food science ,Molecular Biology ,Chemical composition ,Essential oil ,Cell Proliferation ,Jordan ,Ethanol ,Molecular Structure ,biology ,Chemistry ,General Chemistry ,General Medicine ,biology.organism_classification ,Antineoplastic Agents, Phytogenic ,Plant Leaves ,Fruit ,Molecular Medicine ,Composition (visual arts) ,Drug Screening Assays, Antitumor ,Gas chromatography–mass spectrometry ,T47d cell - Abstract
The leaves and unripe and fully-grown fruits of Schinus molle were collected from three geographical regions of Jordan: Amman (the Mediterranean), Madaba (Irano-Turanean), and Sahab (Saharo-Arabian). The hydrodistilled volatile oils of fresh and dried leaves and fruits were analyzed by gas chromatography-mass spectrometry (GC/MS). The actual composition of the emitted volatiles was determined using Solid Phase Micro-Extraction (SPME). α- and β-Phellandrenes were the major components in all the analyzed samples. Quantitative differences were observed in the obtained essential oils (0.62-5.25 %). Additionally, cluster analysis was performed. Biologically, the antiproliferative activity of the essential oil, ethanol, and water extracts of the fruits and leaves was screened on Caco2, HCT116, MCF7, and T47D cell lines. The essential oil and ethanol extracts exhibited a dose-dependent inhibition of cell growth with IC50 ranging between 21 and 65 μg/mL. The water extract did not exhibit any antiproliferative activity against the investigated cell lines.
- Published
- 2019
3. Essential Oil Composition and Anticholinesterase Activity Evaluation of Achillea fragrantissima Growing Wild in Jordan
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Fatma U. Afifi, Musa H. Abu Zarga, Ismail F. Abaza, Mahmoud A. Al-Qudah, Hala I. Al-Jaber, Marwa N. Abu-Aisheh, Amal Al-Aboudi, and Ali F. Al-Shawabkeh
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Pharmacology ,010405 organic chemistry ,Chemistry ,Achillea fragrantissima ,Mass spectrometry ,01 natural sciences ,0104 chemical sciences ,law.invention ,010404 medicinal & biomolecular chemistry ,Complementary and alternative medicine ,Inflorescence ,law ,Botany ,Composition (visual arts) ,Gas chromatography ,Essential oil - Abstract
The composition of hydro-distilled oils of Achillea fragrantissima inflorescence (fresh and dry) at the pre- and flowering stages was evaluated by Gas Chromatography/Mass Spectrometry (GC/MS). Addi...
- Published
- 2018
4. In vitro and in vivo evaluation of the antiangiogenic activities of Trigonella foenum-graecum extracts
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Fatma U. Afifi, Malek Zihlif, Zina A. Habib-Martin, Mohanad M. Saleh, Ismail F. Abaza, Hamzeh J Al-Ameer, Hana Hammad, and Zeyad D. Nassar
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0301 basic medicine ,lcsh:Arctic medicine. Tropical medicine ,Trigonella ,Fenugreek ,lcsh:RC955-962 ,Rat aortic ring assay ,Pharmacology ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,In vivo ,medicine ,MTT assay ,lcsh:QH301-705.5 ,Active ingredient ,Ethanol ,biology ,MCF7 ,biology.organism_classification ,In vitro ,CAM assay ,Chorioallantoic membrane ,030104 developmental biology ,medicine.anatomical_structure ,lcsh:Biology (General) ,Biochemistry ,chemistry ,030220 oncology & carcinogenesis ,Angiogenesis ,Blood vessel - Abstract
Objective To assess the antiangiogenic activity of fenugreek. Methods Different fractions of fenugreek crude extracts were prepared and their antiangiogenic properties were assessed using the ex vivo rat aortic ring assay and in vivo chicken embryo chorioallantoic membrane (CAM) assay. They were investigated for their direct cytotoxic activity in the MCF7 cells using the MTT assay. Results The ethanol extract showed 100% inhibition of blood vessel outgrowth from primary tissue explants in the rat aortic ring assay at a concentration of 100 μg/mL while the other extracts did not show significant antiangiogenic activity. The ethanol extract was therefore investigated at varying concentrations and exhibited a significant dose dependent effect. The CAM assay coincided with the results of the aortic ring assay as ethanol extract showed a significant inhibition of formation of new blood vessels. The extracts only showed anti-proliferative activity at the highest concentration of 400 μg/mL towards MCF7 breast cancer cell lines in the MTT assay. Conclusions Findings of the both assays confirmed that the ethanol extract inhibited vascularization significantly. Further studies on the ethanol extract would be beneficial in isolating the active ingredient responsible for the inhibition.
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- 2017
5. Effect of the Galling Aphid of Baizongia pistaciae L. on Composition and Biological Activities of Essential Oils of Pistacia atlantica Desf. Growing Wild in Jordan
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Ismail F. Abaza, Oriana Awwad, Fatma U. Afifi, Rana Abu-Dahab, Reem Alabbassi, and Lara Majdalawi
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0301 basic medicine ,Aphid ,Limonene ,Obligate ,Host (biology) ,Organic Chemistry ,Sabinene ,Biology ,biology.organism_classification ,Biochemistry ,Analytical Chemistry ,law.invention ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,0302 clinical medicine ,chemistry ,law ,030220 oncology & carcinogenesis ,Botany ,Composition (visual arts) ,Pistacia atlantica ,Essential oil - Abstract
Aqueous extract of Pistacia atlantica leaves is widely used in Jordanian traditional medicine for management of diabetes. The genus Pistaciae serves as obligate host for a group of specialized gall-forming aphids. The present study aimed to identify the aphid attacking P. atlantica trees growing wild in Jordan, to determine the composition of the essential oils from leaves and galls (fresh and dry) and to investigate the antiproliferative activities of the traditionally used dry plant on colon and breast cancers. Hydro-distillation of the essential constituents of P. atlantica leaves was performed and their composition determined. The antiproliferative activity of leaf and galls oils, doxorubicin, and six pure components (sabinene, limonene, α-pinene, β-pinene, α-terpinene, and γ-terpinene) were investigated against two colon (Caco-2 and HCT116) and two breast cancer cell lines (MCF7 and T47D) by MTT assay. Fresh leaf showed the greatest variation in the constituents’ composition. Low molecular we...
- Published
- 2017
6. Patterns in Volatile Emission of Different Organs ofInula viscosagrowing wild in Jordan
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Fatma U. Afifi, Ismail F. Abaza, Musa H. Abu Zarga, Safwan M. Obeidat, Hala I. Al-Jaber, Mahmoud A. Al-Qudah, and Jamil N. Lahham
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Gynoecium ,Inula viscosa ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Sesquiterpene ,01 natural sciences ,Biochemistry ,Terpenoid ,0104 chemical sciences ,Analytical Chemistry ,law.invention ,010404 medicinal & biomolecular chemistry ,chemistry.chemical_compound ,law ,Botany ,Solid Phase Micro Extraction ,Petal ,Chemical composition ,Essential oil - Abstract
In the current investigation, Volatile Organic Compounds (VOCs) spontaneously emitted from the different organs of Inula viscosa growing wild in Jordan were extracted by Solid Phase Micro Extraction (SPME) method and then analyzed using GC-MS technique. Oxygenated monoterpenes dominated roots emission (52.39%) while sesquiterpene hydrocarbons were the main class of compounds detected in the emission of the stems (60.05%). Leaves emission was characterized with high monoterpenoids content (oxygenated 24.34%, hydrocarbons 30.06%). The emission of the fully expanded flowers and flowering organs (receptacles, petals and pistils) was rich in oxygenated monoterpenes (51.96%, 46.94%, 45.45% and 53.13%, respectively). Flowering buds at the pre-flowering stage were rich in oxygenated sesquiterpenoids (40.02%). Principle Component Analysis (PCA) and Cluster Analysis (CA) analysis revealed that the emission profiles of different I. viscosa organs were classified into three clusters based on their chemical co...
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- 2017
7. Investigations on the spontaneous emitted and hydrodistilled volatiles of Platycladus orientalis (L.) Franco grown in four different biogeographic zones of Jordan
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Fatma U. Afifi, Wamidh H. Talib, Osama A. Al-Mahmood, Ismail F. Abaza, and Nour H. Aboalhaija
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chemistry.chemical_classification ,010405 organic chemistry ,Sabinene ,Biology ,Platycladus ,biology.organism_classification ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,law.invention ,010404 medicinal & biomolecular chemistry ,chemistry.chemical_compound ,Hydrocarbon ,chemistry ,law ,Botany ,Gas chromatography ,Ecology, Evolution, Behavior and Systematics ,Essential oil - Abstract
The essential oil of the fresh leaves of Platycladus orientalis (L.), grown in four different biogeographic zones of Jordan,- (the Mediterranean, Irano-Turanian, Saharo-Arabian, and Sudanian penetration) -, were obtained by hydrodistillation and analysed by gas chromatography (GC) and gas chromatography-mass-spectrometry (GC/MS). The actual composition of the spontaneous emitted volatiles was obtained using the solid-phase-micro-extraction (SPME) method and investigated using the same chromatographic and spectroscopic methods. Hydrocarbon monoterpenes dominated the hydrodistilled oils and emissions of all regions. Bicyclic monoterpenes (sabinene, α-pinene, and α-thujene) and monocyclic α-terpinene were detected as the major constituents of the oils and emissions. Additionally, hierarchical cluster analysis (HCA) revealed that the clustering is based on the region of collection rather than the applied methodology. Differences were observed in the quantity of the obtained oils (P-values
- Published
- 2020
8. Antiobesity and antihyperglycaemic effects of Adiantum capillus-veneris extracts: in vitro and in vivo evaluations
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Entisar K Al-Hallaq, Ismail F. Abaza, Violet Kasabri, Khalid K. Abdul-Razzak, Fatma U. Afifi, and Yasser Bustanji
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Blood Glucose ,0301 basic medicine ,Time Factors ,Pharmaceutical Science ,adiantaceae ,Pharmacology ,Weight Gain ,pancreatic lipase and amylase ,01 natural sciences ,Adiantum ,chemistry.chemical_compound ,Drug Discovery ,Adiantaceae ,Acarbose ,Glucose tolerance test ,biology ,medicine.diagnostic_test ,General Medicine ,Biochemistry ,Molecular Medicine ,high cholesterol diet ,Research Article ,medicine.drug ,phenolics ,Diet, High-Fat ,03 medical and health sciences ,Chlorogenic acid ,In vivo ,medicine ,Animals ,Hypoglycemic Agents ,Glycoside Hydrolase Inhibitors ,Obesity ,Rats, Wistar ,Pancreas ,Triglycerides ,Plants, Medicinal ,030109 nutrition & dietetics ,Guar gum ,Dose-Response Relationship, Drug ,Plant Extracts ,lcsh:RM1-950 ,Lipase ,Glucose Tolerance Test ,Plant Components, Aerial ,biology.organism_classification ,0104 chemical sciences ,Disease Models, Animal ,010404 medicinal & biomolecular chemistry ,lcsh:Therapeutics. Pharmacology ,Complementary and alternative medicine ,chemistry ,Anti-Obesity Agents ,alpha-Amylases ,Biomarkers ,Phytotherapy ,Glipizide - Abstract
Context: Adiantum capillus-veneris L. (Adiantaceae) hypocholesterolemic activity is therapeutically praised. Objectives: Pharmacological modulation of pancreatic triacylglycerol lipase (PL) and α-amylase/α-glucosidase by A. capillus-veneris are evaluated. Materials and methods: Using positive controls (acarbose, orlistat, guar gum, atorvastatin, glipizide and metformin) as appropriate, crude aqueous extracts (AEs) of A. capillus-veneris aerial parts were tested via a combination of in vitro enzymatic (0.24–100 mg/mL), acute in vivo carbohydrate tolerance tests (125, 250 or 500 mg/kg body weight [b.wt]) and chronic in vivo studies (500 mg/kg b.wt) in high cholesterol diet (HCD) fed Wistar rats. Results: Like acarbose, A. capillus-veneris as well as chlorogenic acid, with respective IC50 values (mg/mL) of 0.8 ± 0.0 and 0.2 ± 0.0, were identified as in vitro potent dual inhibitors of α-amylase/α-glucosidase. Unlike guar gum, A. capillus-veneris had no glucose diffusion hindrance capacity. Equivalent to orlistat, A. capillus-veneris and its phytoconstituents inhibited PL in vitro with an ascending order of PL- IC50 values (μg/mL): ferulic acid; 0.48 ± 0.06
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- 2016
9. Achillea santolina: Growth Dependent Variation in Essential Oil Composition and Some in–vitro Bioactivity Studies
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Hana Hammad, Dima Khater, Hala I. Al-Jaber, M. Abu-Zarga, Mohammad Barham, Ayman M. Saleh, Jehan Y. Al-Humaidi, Fatma U. Afifi, Mahmoud A. Al-Qudah, and Ismail F. Abaza
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010404 medicinal & biomolecular chemistry ,010405 organic chemistry ,law ,Chemistry ,Achillea santolina ,Botany ,Composition (visual arts) ,01 natural sciences ,Essential oil ,In vitro ,0104 chemical sciences ,law.invention - Published
- 2016
10. Characterizing Inhibitor Content of Transformer Oil in the UV-Visible Waveband
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Yang Sing Leong, M. Looe, Hasan Muhammad Abdullah, Md. Zaini Jamaludin, C. K. Lo, Pin Jern Ker, Saiffuddin M, Nomanbhay A, and Ismail F
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010302 applied physics ,Materials science ,Moisture ,Transformer oil ,Analytical chemistry ,chemistry.chemical_element ,02 engineering and technology ,Dielectric ,021001 nanoscience & nanotechnology ,01 natural sciences ,Oxygen ,law.invention ,Absorbance ,chemistry ,law ,0103 physical sciences ,0210 nano-technology ,Spectroscopy ,Transformer ,Oxidation rate - Abstract
Over the years, transformer oil has been used in majority of the power transformers to provide a reliable insulating system that is effective against dielectric stresses. Oxidation often occurred in transformer oil in the presence of oxygen and moisture which will affect the stability and insulating properties of the oil. The oxidation process cannot be eliminated but it can be delayed with the presence of inhibitor content. Even though inhibitor content can reduce the oxidation rate, the amount of inhibitor content still depletes over time. Thus, a monitoring system to detect the inhibitor content concentration is very crucial as it will be able to prolong the life span of the transformer. This paper focuses on the optical characterization of inhibitor content in transformer oil by utilizing the ultravioletvisible (UV-Vis) spectroscopy technique. It was found that oil samples with inhibitor content produce multiple absorbance peaks in the range of 350 nm to 500 nm. A clear difference in peak absorbance near 450 nm indicates the difference in the inhibitor content concentrations. Based on the results of this work, a portable and low cost optical sensing device can potentially be developed for the detection of inhibitor content in transformer oil using UV-Vis spectroscopy.
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- 2018
11. Phytochemical Analysis and Evaluation of Anti-angiogenic and Antiproliferative Activities of the Leaves of Elaeagnus angustifolia L. Grown in Jordan
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Ismail F. Abaza, Zeyad D. Nassar, Malek Al-Zihlif, Aman A Ishaqat, Hana Hammad, Fatma U. Afifi, and Rana Abu-Dahab
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Terpene ,chemistry.chemical_compound ,Rutin ,Column chromatography ,chemistry ,Traditional medicine ,Phytochemical ,Ethyl acetate ,Maceration (wine) ,Kaempferol ,Luteolin - Abstract
Elaeagnus angustifolia L. has a long history of use in ethnopharmacology. Only few studies examined the potential activities of the leaves. Furthermore, the leaves’ chemical composition was not fully investigated. In this study, the chemical composition of E. angustifolia leaves extract was analysed and major compounds were isolated and identified. Extract obtained by maceration was further extracted with solvents differing in their polarity then submitted to open column chromatography, followed by isolation of major compounds. They were analysed using UV-Vis and/or NMR. One terpene (β-sitosterol) and four flavonoids (chrysin-7-glucoside, rutin, luteolin and kaempferol) were isolated and identified. For the biological activities, leaves were extracted using ethanol, ethyl acetate, chloroform and water. Anti-angiogenic activity was studied by rat aortic ring assay. Anti-proliferative activity was studied against MCF-7 and T-47D breast cancer cell lines. Ethyl acetate extract was found cytotoxic against T-47D breast cancer cell line (IC50=23.05 μg/mL). Potent anti-angiogenic activity of ethanol-(IC50=3.039 μg/mL), ethyl acetate- (IC50=6.289 μg/mL) and water-extract (IC50=7.153 μg/mL) was reported for the first time.
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- 2018
12. Volatile Oil Composition and Antiplatelet Activity of JordanianAchillea biebersteiniiCollected at Different Growth Stages
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Fatma U. Afifi, Hana Hammad, Hala I. Al-Jaber, Jehan Y. Al-Humaidi, Ismail F. Abaza, M. Abu-Zarga, and Mahmoud A. Al-Qudah
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Achillea biebersteinii ,biology ,Monoterpene ,Organic Chemistry ,Asteraceae ,biology.organism_classification ,Biochemistry ,Analytical Chemistry ,law.invention ,chemistry.chemical_compound ,chemistry ,law ,Stomach ache ,Botany ,Composition (visual arts) ,Ascaridole ,Healing wounds ,Essential oil - Abstract
Achillea biebersteinii Afan. (Asteraceae) is used as a traditional medicine for healing wounds and in the treatment of abdominal pain and stomach ache. Fresh and air dried flowering parts of A. biebersteinii at different growth stages were subjected to hydro-distillation and the different essential oils obtained were analyzed by GC-MS technique. Monoterpenoids dominated the different flowering stages of both, fresh and air dried flowering parts. The fresh pre-flowering stage was dominated by monoterpene hydrocarbons (56.62 %) with α-terpinene as the major component (51.67 %). Oxygenated monoterpenes were detected as the principal constituents during both, the fresh flowering and fresh post-flowering stages (55.61 %, 56.45 %, respectively). The major representatives of this class included ascaridol (38.84 %) and iso-ascaridol (25.39 %). Oxygenated monoterpenes dominated all flowering stages of the air-dried blooms and ascaridol was the main volatile compound in these oils (28.20 %, 27.03 % and 44.3...
- Published
- 2014
13. Chemical Composition Analysis and Antimicrobial Screening of the Essential Oil of a Rare Plant from Jordan:Ducrosia flabellifolia
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Fatma U. Afifi, Mustafa Al-Shudiefat, Khalid M Al-Khalidi, and Ismail F. Abaza
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Apiaceae ,Chromatography ,biology ,Chemistry ,Biochemistry (medical) ,Clinical Biochemistry ,Decanal ,Dodecanal ,biology.organism_classification ,Solid-phase microextraction ,Biochemistry ,Analytical Chemistry ,law.invention ,chemistry.chemical_compound ,law ,Electrochemistry ,Gas chromatography ,Gas chromatography–mass spectrometry ,Chemical composition ,Spectroscopy ,Essential oil - Abstract
The composition of the essential oil isolated from the fresh and dry leaves of Ducrosia flabellifolia Boiss. (Apiaceae) was determined by gas chromatography and gas chromatography–mass spectrometry using hydrodistillation and solid phase microextraction (SPME). The hydrodistilled oil of the fresh leaves yielded 38 components, accounting for 98.67% of the total oil content, while thirty components were detected from the fresh leaves by solid phase microextraction (94.85%). Fifty-one and 36 components were identified in the hydrodistilled and SPME oils of the dried leaves amounting to 98.78% and 94.52%, respectively. A total of 25 components accounting for 97.24% of the total composition were characterized in the SPME oil of the fresh flowers. Aliphatic compounds predominated in the volatile fractions of the leaves and flowers of both methods with n-decanol, n-decanal, and dodecanal as the main constituents. The α- and s-pinene were the major monoterpenoids in the oils. The hydrodistilled oil was screened f...
- Published
- 2014
14. Chemical Composition, Antimicrobial and Antitumor Activities of Essential Oil ofAmmodaucus leucotrichusGrowing in Algeria
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Zahra Y. Baba Amer, Fatma U. Afifi, Lakhdar. Sakhrib, Jehan Y. Al-Humaidi, Mahmoud A. Al-Qudah, Hala I. Al-Jaber, Musa H. Abu Zarga, and Ismail F. Abaza
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Pharmacology ,Chromatography ,Apiaceae ,biology ,Monoterpene ,Plant Science ,Perillaldehyde ,Ammodaucus ,Toxicology ,biology.organism_classification ,Antimicrobial ,Agricultural and Biological Sciences (miscellaneous) ,law.invention ,chemistry.chemical_compound ,Complementary and alternative medicine ,chemistry ,law ,Drug Discovery ,Food science ,Gas chromatography–mass spectrometry ,Micrococcus luteus ,Essential oil - Abstract
Ammodaucus leucotrichus L. (Apiaceae) is a rarely investigated important medicinal plant endemic to North African countries. The essential oil of A. leucotrichus L. seeds obtained by hydro-distillation and SPME extraction methods were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS) technique. Twenty two components were identified in the hydro-distilled oil amounting to 97.04 % of the total oil content. The oil was dominated by oxygenated monoteprenes (87.32 %) represented by perilla aldehyde (84.43 %). A total of thirty four components accounting for 99.88 % of the total composition were characterized in the SPME oil. Monoterpene hydrocarbons had the highest contribution to the SPME oil (87.40 %) with terpinolene being the main component of the fraction (69.21%). The hydro-distilled oil was screened for its antimicrobial activity and was found to be inactive against Escherichia coli, Pseudomonas aeruginosa and Salmonella typhi. The pure oil was most active against Micrococcus luteus while moderat...
- Published
- 2013
15. Variation in the essential oil composition ofEremostachys laciniatafrom Jordan at different flowering stages
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Mahmoud A. Al-Qudah, Fatma U. Afifi, Hala I. Al-Jaber, Lina M. Barhoumi, and Ismail F. Abaza
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Limonene ,biology ,Monoterpene ,fungi ,food and beverages ,General Chemistry ,biology.organism_classification ,Sesquiterpene ,Terpenoid ,law.invention ,chemistry.chemical_compound ,chemistry ,law ,Botany ,Lamiaceae ,Composition (visual arts) ,Gas chromatography–mass spectrometry ,Essential oil - Abstract
Fresh aerial parts of Eremostachys laciniata Bunge growing wild in Jordan (Lamiaceae) were collected at different flowering stages. The essential oil contents of the fresh and the air-dried plants at the flowering stage were analyzed using gas chromatography–mass spectrometry (GC–MS). Results obtained indicated variability in the terpenoid content at the different flowering stages. Monoterpene hydrocarbons were the main group of all terpenoids during the pre-flowering, fresh flowering and air-dried-flowering stages (12.1%, 24.3% and 16.0%, respectively) and reached a minimum value at the post-flowering stage (2.5%) with limonene being the major compound in this fraction at all stages. Sesquiterpene hydrocarbons reached a maximum level at the fresh flowering stage (10.0%) with α-copaene (3.0%) as the the major component during this stage. Oxygenated monoterpenes were detected in highest concentration after air-drying (14.4%), whereas the oxygenated sesquiterpene content reached 5.5% at the post-flowering s...
- Published
- 2012
16. Impact of testosterone on cardiac L-type calcium channels and Ca2+ sparks: Acute actions antagonize chronic effects
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Michael Lindner, Fikret Er, Mathias C. Brandt, Hannelore Haase, Ismail F. Y. Khan, Uta C. Hoppe, Guido Michels, and Michael Eicks
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medicine.medical_specialty ,Calcium Channels, L-Type ,Physiology ,chemistry.chemical_element ,Calcium ,Flutamide ,Rats, Sprague-Dawley ,Contractility ,chemistry.chemical_compound ,Internal medicine ,Animals ,Medicine ,Myocytes, Cardiac ,Testosterone ,L-type calcium channel ,Calcium Signaling ,Molecular Biology ,Cells, Cultured ,Calcium metabolism ,Voltage-dependent calcium channel ,business.industry ,Calcium channel ,Testosterone (patch) ,Cell Biology ,Myocardial Contraction ,Rats ,Endocrinology ,Animals, Newborn ,chemistry ,Female ,business ,Ion Channel Gating - Abstract
While androgens generally have been associated with an increased cardiovascular risk, recent studies indicate potential beneficial acute effects of testosterone. However, detailed evaluation of chronic and acute actions of testosterone on the function of cardiac I(Ca,L) and intracellular Ca2+ handling is limited. To clarify this situation we performed whole-cell and single-channel analysis of I(Ca,L), recordings of Ca2+ sparks, measurements of contractility and quantitative real-time RT-PCR in rat cardiomyocytes following testosterone pretreatment and acute testosterone application. Pretreatment with testosterone 100 nM for 24-30 h increased whole-cell I(Ca,L) from 3.8+/-0.8 pA/pF (n=10) to 10.1+/-0.31 pA/pF (n=9) at +10 mV (p
- Published
- 2007
17. Cardiac L-type Calcium Channel β-Subunits Expressed in Human Heart Have Differential Effects on Single Channel Characteristics
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Roger Hullin, Arnold Schwartz, Stefan Herzig, Paul Mohacsi, Ismail F. Y. Khan, Gyula Varadi, and Susanne Wirtz
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Gene isoform ,medicine.medical_specialty ,Calcium Channels, L-Type ,Heart Ventricles ,chemistry.chemical_element ,CHO Cells ,Gating ,Calcium ,Biology ,N-type calcium channel ,Transfection ,Polymerase Chain Reaction ,Biochemistry ,Cell Line ,Cricetinae ,Internal medicine ,medicine ,Animals ,Humans ,Protein Isoforms ,L-type calcium channel ,RNA, Messenger ,Cloning, Molecular ,Molecular Biology ,Voltage-dependent calcium channel ,Reverse Transcriptase Polymerase Chain Reaction ,Myocardium ,T-type calcium channel ,Exons ,Cell Biology ,Blotting, Northern ,Recombinant Proteins ,Cell biology ,Electrophysiology ,R-type calcium channel ,Endocrinology ,chemistry ,Calcium Channels ,Rabbits ,Gene Deletion - Abstract
l-Type calcium channels are multiprotein complexes composed of pore-forming (CaV1.2) and modulatory auxiliary alpha2delta- and beta-subunits. We demonstrate expression of two different isoforms for the beta2-subunit (beta2a, beta2b) and the beta3-subunit (beta3a, beta3trunc) in human non-failing and failing ischemic myocardium. Quantitatively, in the left ventricle expression of beta2b transcripts prevails in the order of > beta3 >> beta2a. The expressed cardiac full-length beta3-subunit is identical to the beta3a-isoform, and beta3trunc results from deletion of exon 6 (20 nn) entailing a reading frameshift and translation stop at nucleotide position 495. In failing ischemic myocardium beta3trunc expression increases whereas overall beta3 expression remains unchanged. Heterologous coexpression studies demonstrated that beta2 induced larger currents through rabbit and human cardiac CaV1.2 pore subunits than beta3 isoforms. All beta-subunits increased channel availability at single channel level, but beta2 exerted an additional, marked stimulation of rapid gating (open and closed times, first latency), leading to higher peak current values. We conclude that cardiac beta-subunit isoforms differentially modulate calcium inward currents because of regulatory effects within the channel protein complex. Moreover, differences in the various beta-subunit gene products present in human heart might account for altered single channel behavior found in human heart failure.
- Published
- 2003
18. Phytochemical and biological evaluations of Arum hygrophilum boiss. (Araceae)
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Violet Kasabri, Fatma U. Afifi, Khalid Tawaha, Ismail F. Abaza, and Simona Carmen Litescu
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ABTS ,Chromatography ,010405 organic chemistry ,DPPH ,Isoorientin ,Rosmarinic acid ,Trolox equivalent antioxidant capacity ,Vitexin ,Pharmaceutical Science ,01 natural sciences ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,chemistry.chemical_compound ,chemistry ,Phytochemical ,Biochemistry ,Drug Discovery ,Lipid digestion - Abstract
Background: Arum hygrophilum is a traditional medicinal plant indigenous to Jordan. The present study explores its phytochemistry, antioxidative, antidiabesity, and antiproliferative potentialities. Materials and Methods: Column chromatography and HPLC-MS analysis were used for its phytochemical evaluation. Using leaf crude water and ethanol extracts, the antioxidative capacities, their modulation of pancreatic β-cell proliferation, and insulin secretion as well as glucose diffusion and enzymatic bioassays were evaluated. Results: Three flavonoids (luteolin, isoorientin, and vitexin) and β-sitosterol have been isolated and their structures determined. HPLC-MS analysis of the ethanol extract further revealed the presence of caffeic, ferulic, gallic, and rosmarinic acids and quercetine-3-O-rhamnoside. The ethanol extract exhibited DPPH and ABTS radical scavenging and antioxidative capacities. A. hygrophilum (1), vitexin (2), and rosmarinic acid (3) inhibited pancreatic lipase (PL) dose dependently with PL-IC 50 (µg/mL) values in an ascending order: (3); 51.28 ± 7.55 A. hygrophilum aqueous extract (AE) (0.5 and 1 mg/mL, with respective 1.33- and 1.41-folds, P A. hygrophilum AE was identified as an inhibitor of α-amylase/α-glucosidase with IC 50 value of 30.5 ± 2.1 mg/mL but lacked antiproliferative effects in colorectal cancer cell lines (HT29, HCT116, and SW620) and insulinotropic effects in β-cell line MIN6. Conclusion: A. hygrophilum extracts inhibited gastrointestinal enzymes involved in carbohydrate and lipid digestion and absorption. Abbreviations used: ABTS: 2,2'-Azino-Bis-3-Ethylbenzothiazoline-6-Sulfonic Acid, AE: Aqueous Extract, ANOVA: Analysis Of Variance, AUC: Area Under Curve, BrdU: 5-Bromo-2'-Deoxyuridine, DPPH: 2,2-Diphenyl -1-Pycriylhydrazyl, ELISA: Enzyme Linked Immunosorbent Assay, GLP1: Glucagon Like Peptide 1, GSIS: Glucose Stimulated Insulin Secretion, HPLC-MS: High Performance Liquid Chromatography-Mass Spectrometry, IC50: 50% Inhibitory Concentration, KRH: Krebs/Ringer/Hepes, MTT: 3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide, OGTT: Oral Glucose Tolerance Test, ORAC: Oxygen Radical Antioxidant Capacity, OSTT: Oral Starch Tolerance Test, PL: Pancreatic Lipase, SEM: Standard Error Of The Mean, SRB: Sulforhodamine B, TEAC: Trolox Equivalent Antioxidant Capacity, TLC: Thin Layer Chromatography
- Published
- 2017
19. Inactivation of L-type calcium channels is determined by the length of the N terminus of mutant beta(1) subunits
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Stefan Herzig, Wanchana Jangsangthong, Roger Hullin, Ismail F. Y. Khan, Jan Matthes, and Elza Kuzmenkina
- Subjects
Patch-Clamp Techniques ,Calcium Channels, L-Type ,Physiology ,Protein subunit ,Clinical Biochemistry ,Mutant ,Molecular Sequence Data ,Gating ,N-type calcium channel ,Cell Line ,Physiology (medical) ,Humans ,Protein Isoforms ,L-type calcium channel ,Amino Acid Sequence ,Voltage-dependent calcium channel ,Chemistry ,Calcium channel ,Molecular biology ,Markov Chains ,R-type calcium channel ,Alternative Splicing ,Protein Subunits ,Mutation ,Biophysics ,Ion Channel Gating - Abstract
Voltage-dependent calcium channel (Ca(v)) pores are modulated by cytosolic beta subunits. Four beta-subunit genes and their splice variants offer a wide structural array for tissue- or disease-specific biophysical gating phenotypes. For instance, the length of the N terminus of beta(2) subunits has major effects on activation and inactivation rates. We tested whether a similar mechanism principally operates in a beta(1) subunit. Wild-type beta(1a) subunit (N terminus length 60 aa) and its newly generated N-terminal deletion mutants (51, 27 and 18 aa) were examined within recombinant L-type calcium channel complexes (Ca(v)1.2 and alpha(2)delta2) in HEK293 cells at the whole-cell and single-channel level. Whole-cell currents were enhanced by co-transfection of the full-length beta(1a) subunit and by all truncated constructs. Voltage dependence of steady-state activation and inactivation did not depend on N terminus length, but inactivation rate was diminished by N terminus truncation. This was confirmed at the single-channel level, using ensemble average currents. Additionally, gating properties were estimated by Markov modeling. In confirmation of the descriptive analysis, inactivation rate, but none of the other transition rates, was reduced by shortening of the beta(1a) subunit N terminus. Our study shows that the length-dependent mechanism of modulating inactivation kinetics of beta(2) calcium channel subunits can be confirmed and extended to the beta(1) calcium channel subunit.
- Published
- 2009
20. Regulation of the human cardiac mitochondrial Ca2+ uptake by 2 different voltage-gated Ca2+ channels
- Author
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Jeannette Endres-Becker, Stefan Herzig, Thorsten Wahlers, Arjang Ruhparwar, Dennis Rottlaender, Uta C. Hoppe, Ismail F. Y. Khan, and Guido Michels
- Subjects
Cardiomyopathy, Dilated ,medicine.medical_specialty ,Ruthenium red ,Patch-Clamp Techniques ,Biophysics ,Myocardial Ischemia ,Gating ,Biology ,Mitochondrion ,In Vitro Techniques ,chemistry.chemical_compound ,Physiology (medical) ,Internal medicine ,medicine ,Humans ,Myocytes, Cardiac ,Patch clamp ,Uniporter ,Ion channel ,Heart Failure ,Voltage-gated ion channel ,Voltage-dependent calcium channel ,Ruthenium Red ,Mitochondria ,Kinetics ,Endocrinology ,chemistry ,Calcium ,Indicators and Reagents ,Calcium Channels ,Cardiology and Cardiovascular Medicine ,Ion Channel Gating - Abstract
Background— Impairment of intracellular Ca 2+ homeostasis and mitochondrial function has been implicated in the development of cardiomyopathy. Mitochondrial Ca 2+ uptake is thought to be mediated by the Ca 2+ uniporter (MCU) and a thus far speculative non-MCU pathway. However, the identity and properties of these pathways are a matter of intense debate, and possible functional alterations in diseased states have remained elusive. Methods and Results— By patch clamping the inner membrane of mitochondria from nonfailing and failing human hearts, we have identified 2 previously unknown Ca 2+ -selective channels, referred to as mCa1 and mCa2. Both channels are voltage dependent but differ significantly in gating parameters. Compared with mCa2 channels, mCa1 channels exhibit a higher single-channel amplitude, shorter openings, a lower open probability, and 3 to 5 subconductance states. Similar to the MCU, mCa1 is inhibited by 200 nmol/L ruthenium 360, whereas mCa2 is insensitive to 200 nmol/L ruthenium 360 and reduced only by very high concentrations (10 μmol/L). Both mitochondrial Ca 2+ channels are unaffected by blockers of other possibly Ca 2+ -conducting mitochondrial pores but were activated by spermine (1 mmol/L). Notably, activity of mCa1 and mCa2 channels is decreased in failing compared with nonfailing heart conditions, making them less effective for Ca 2+ uptake and likely Ca 2+ -induced metabolism. Conclusions— Thus, we conclude that the human mitochondrial Ca 2+ uptake is mediated by these 2 distinct Ca 2+ channels, which are functionally impaired in heart failure. Current properties reveal that the mCa1 channel underlies the human MCU and that the mCa2 channel is responsible for the ruthenium red–insensitive/low-sensitivity non-MCU–type mitochondrial Ca 2+ uptake.
- Published
- 2009
21. Direct evidence for calcium conductance of hyperpolarization-activated cyclic nucleotide-gated channels and human native If at physiological calcium concentrations
- Author
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Naufal Zagidullin, Ismail F. Y. Khan, Guido Michels, Jens Wippermann, Mathias C. Brandt, Robert Larbig, Uta C. Hoppe, and Sebastian van Aaken
- Subjects
Male ,medicine.medical_specialty ,Cell Membrane Permeability ,Patch-Clamp Techniques ,Potassium Channels ,Physiology ,chemistry.chemical_element ,Cyclic Nucleotide-Gated Cation Channels ,CHO Cells ,Calcium ,Transfection ,Ion Channels ,Membrane Potentials ,Rats, Sprague-Dawley ,Cyclic nucleotide ,chemistry.chemical_compound ,Pacemaker potential ,Mice ,Cricetulus ,Physiology (medical) ,Internal medicine ,Cricetinae ,medicine ,Cyclic AMP ,Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels ,Animals ,Humans ,Ivabradine ,Myocytes, Cardiac ,Calcium Signaling ,Reversal potential ,Ion channel ,Aged ,Membrane potential ,Aged, 80 and over ,Sodium ,Conductance ,Hyperpolarization (biology) ,Benzazepines ,Rats ,Endocrinology ,chemistry ,Animals, Newborn ,Biophysics ,Potassium ,Female ,Cardiology and Cardiovascular Medicine - Abstract
The hyperpolarization-activated cyclic nucleotide-gated (HCN) current I(f)/I(HCN) is generally thought to be carried by Na(+) and K(+) under physiological conditions. Recently, Ca(2+) influx through HCN channels has indirectly been postulated. However, direct functional evidence of Ca(2+) permeation through I(f)/I(HCN) is still lacking.To possibly provide direct evidence of Ca(2+) influx through I(HCN)/I(f), we performed inside-out and cell-attached single-channel recordings of heterologously expressed HCN channels and native rat and human I(f), since Ca(2+)-mediated I(f)/I(HCN) currents may not readily be recorded using the whole-cell technique. Original current traces demonstrated HCN2 Ca(2+) inward currents upon hyperpolarization with a single-channel amplitude of -0.87+/-0.06 pA, a low open probability of 3.02+/-0.48% (at -110 mV, n=6, Ca(2+) 2 mmol/L), and a Ca(2+) conductance of 8.9+/-1.2 pS. I(HCN2-Ca2+) was significantly activated by the addition of cAMP with an increase in the open probability and suppressed by the specific I(f) inhibitor ivabradine, clearly confirming that Ca(2+) influx indeed was conducted by HCN2 channels. Changing [Na(+)] (10 vs. 100 mmol/L) in the presence or absence of 2 mmol/L Ca(2+) caused a simple shift of the reversal potential along the voltage axis without significantly affecting Na(+)/Ca(2+) conductance, whereas the K(+) conductance of HCN2 increased significantly in the absence of external Ca(2+) with increasing K(+) concentrations. The mixed K(+)-Ca(2+) conductance, however, was unaffected by the external K(+) concentration. Notably, we could also record hyperpolarization-activated Ca(2+) permeation of single native I(f) channels in neonatal rat ventriculocytes and human atrial myocytes in the presence of blockers for all known cardiac calcium conduction pores (Ca(2+) conductance of human I(f), 9.19+/-0.34 pS; amplitude, -0.81+/-0.01 pA; open probability, 1.05+/-0.61% at -90 mV).We directly show Ca(2+) permeability of native rat and, more importantly, human I(f) at physiological extracellular Ca(2+) concentrations at the physiological resting membrane potential. This might have particular implications in diseased states with increased I(f) density and HCN expression.
- Published
- 2008
22. Mechanism of Ca(v)1.2 channel modulation by the amino terminus of cardiac beta2-subunits
- Author
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Uta C. Hoppe, Roger Hullin, Dirk Gründemann, David T. Yue, Stefan Herzig, Guido Michels, Dipayan Chaudhuri, Arnold M. Schwartz, Ismail F. Y. Khan, Jan Matthes, and Andreas Ludwig
- Subjects
Adult ,Male ,Calcium Channels, L-Type ,RNA Splicing ,Gene Expression ,Gating ,N-type calcium channel ,Biochemistry ,Cav1.2 ,Cell Line ,Genetics ,medicine ,Humans ,Q-type calcium channel ,Cloning, Molecular ,Molecular Biology ,DNA Primers ,Stochastic Processes ,biology ,Voltage-dependent calcium channel ,Base Sequence ,Chemistry ,Calcium channel ,Myocardium ,Dihydropyridine ,R-type calcium channel ,biology.protein ,Biophysics ,Ion Channel Gating ,Biotechnology ,medicine.drug - Abstract
L-type calcium channels are composed of a pore, alpha1c (Ca(V)1.2), and accessory beta- and alpha2delta-subunits. The beta-subunit core structure was recently resolved at high resolution, providing important information on many functional aspects of channel modulation. In this study we reveal differential novel effects of five beta2-subunits isoforms expressed in human heart (beta(2a-e)) on the single L-type calcium channel current. These splice variants differ only by amino-terminal length and amino acid composition. Single-channel modulation by beta2-subunit isoforms was investigated in HEK293 cells expressing the recombinant L-type ion conducting pore. All beta2-subunits increased open probability, availability, and peak current with a highly consistent rank order (beta2a approximately = beta2b > beta2e approximately = beta2c > beta2d). We show graded modulation of some transition rates within and between deep-closed and inactivated states. The extent of modulation correlates strongly with the length of amino-terminal domains. Two mutant beta2-subunits that imitate the natural span related to length confirm this conclusion. The data show that the length of amino termini is a relevant physiological mechanism for channel closure and inactivation, and that natural alternative splicing exploits this principle for modulation of the gating properties of calcium channels.
- Published
- 2007
23. Oxidation of iron in biotite by different oxidizing solutions at room temperature
- Author
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Scott, A. D., Ismail, F. T., and Amonette, J.
- Subjects
BIOTITE ,CHEMISTRY ,MINERALOGY - Published
- 1985
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