Howaida Ibrahim Abd-Alla

Prof. Dr. Howaida Ibrahim Abd-Alla

Department of Chemistry of Natural Compounds, National Research Center, Cairo, Egypt

Research Focus & Metrics

Academic Career Length

1Year (2026-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 August 2009 in Zeitschrift für Naturforschung C
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Howaida Ibrahim Abd-AllaHowaida Ibrahim Abd-Alla
Howaida Ibrahim Abd-Alla
FMFatma Moharram
Fatma Moharram
AGAhmed H. Gaara
Ahmed H. Gaara
MEMounir M. El-Safty
Mounir M. El-Safty
A novel biflavone di-C-glucoside, 6,6″-di-C-β-D-glucopyranoside-methylene-(8,8″)- biapigenin (1), was isolated from the leaves of Jatropha curcas L. (Euphorbiaceae), together with six known compounds; apigenin 7-O-β-D-neohesperidoside (2), apigenin 7-O-β-Dgalactoside (3), orientin (4), vitexin (5), vicenin II (6), and apigenin (7). Their structures were determined on the basis of extensive chemical and spectroscopic analyses (UV, NMR and HRESI-MS). The immunomodulatory effect of an 80% aqueous methanol extract (AME) and compounds 1 - 5 (0.25 mg/kg body wt) to one-day-old specific pathogen-free (SPF) chicks was determined. Stimulation of both humoral and cell-mediated seroresponse was observed, especially those of AME and compound 1. Remarkable effective increases of the antibody titers, lymphocyte and macrophage cells, in blood were recorded. SPF chicks treated with the tested samples exhibited protection against Newcastle disease challenge virus after being vaccinated.

1 November 2021 in Archives of Pharmacal Research
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Howaida Ibrahim Abd-AllaHowaida Ibrahim Abd-Alla
Howaida Ibrahim Abd-Alla
DSDalila Souguir
Dalila Souguir
Mohamed O. RadwanMohamed O. Radwan
Mohamed O. Radwan

1 January 2014 in BioMed Research International
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NSNagwa M. M. Shalaby
Nagwa M. M. Shalaby
Howaida Ibrahim Abd-AllaHowaida Ibrahim Abd-Alla
Howaida Ibrahim Abd-Alla
HAHanan Aly
Hanan Aly
MAMarzougah A. Albalawy
Marzougah A. Albalawy
KSKamel Shaker
Kamel Shaker
Jalloul BouajilaJalloul Bouajila
Jalloul Bouajila
Aim.Ducrosia anethifoliais used as flavoring additive. There have been little detailed phytochemical reports on this genus and the antidiabetic activity of this plant is not yet evaluated.Method. Structure of compounds was deduced by spectroscopic analyses. Preliminaryin vitroevaluation of the antidiabetic activity of crude extract and its furanocoumarins was carried out (α-amylase,α-glucosidase, andβ-galactosidase). Thein vivoactivity was investigated by measuring some oxidative stress markers. Biomarkers of liver injury and kidney were also determined.Results. Eight linear furanocoumarins, psoralen, 5-methoxypsoralen, 8-methoxypsoralen, imperatorin, isooxypeucedanin, pabulenol, oxypeucedanin methanolate, oxypeucedanin hydrate, and 3-O-glucopyranosyl-β-sitosterol, were isolated. All compounds were reported for the first time from the genusDucrosiaexcept pabulenol. The blood glucose level, liver function enzymes, total protein, lipid, and cholesterol levels were significantly normalized by extract treatment. The antioxidant markers, glucolytic, and gluconeogenic enzymes were significantly ameliorated and the elevated level of kidney biomarkers in the diabetic groups was restored. The compounds showed inhibitory activity in a concentration dependant manner. Imperatorin and 5-methoxypsoralen showed the most potent inhibiting power.Conclusion.D. anethifoliaextract showed hypoglycemic, hypolipidemic, and antioxidant effect as well as ameliorating kidney function. This extract and some linear furanocoumarins exhibited carbohydrate metabolizing enzymes inhibitory effect.

20 July 2009 in Natural Product Research
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Howaida Ibrahim Abd-AllaHowaida Ibrahim Abd-Alla
Howaida Ibrahim Abd-Alla
MSMohamed Shaaban
Mohamed Shaaban
Khaled A. ShaabanKhaled A. Shaaban
Khaled A. Shaaban
NANagat S. Abu-Gabal
Nagat S. Abu-Gabal
NSNagwa M.M. Shalaby
Nagwa M.M. Shalaby
HLHartmut Laatsch
Hartmut Laatsch
The chemical constituents and biological activities of leaves and roots of Aloe hijazensis, collected in Saudi Arabia, are reported here for the first time. Twenty-two compounds were obtained, among them eight hydroxyquinones: aloe-emodin (1), emodin (2), chrysophanol (3), aloesaponarin II 3-methyl ether (4), ziganein (5), ziganein-5-methyl ether (6a), aloesaponarin I (7) and chrysophanein (8), the dihydro-isocoumarin feralolide (9), 4,7-dichloro-quinoline (10), the triterpene lupeol (11), the anthrone aloin (12), three aloenin derivatives, aloenin (13) ethylidene-aloenin (14), and aloenin B (15), four flavonoids, quercetin (16), kaempferol (17) cosmosiin (18) and isovitexin (19), and cinnamic acid (20) and two further analogues, caffeic acid (21) and ferulic acid (22). While 15 of the isolated compounds were found in the leaves, 12 were isolated from roots of the plant. Compounds 6a and 10 are reported as new natural constituents, while the compounds 4, 5, 8, and 18 are reported here for the first time from Aloe spp. The structures of the compounds were deduced by intensive studies of their UV, NMR, MS data and by comparison with related structures. The biological activity of plant extracts was studied against various microbial strains, and potent anti-bacterial and anti-fungal activities were found.

8 January 2015 in Archives of Pharmacal Research
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Howaida Ibrahim Abd-AllaHowaida Ibrahim Abd-Alla
Howaida Ibrahim Abd-Alla
NSNagwa M. M. Shalaby
Nagwa M. M. Shalaby
Manal HamedManal Hamed
Manal Hamed
NENagy Saba El-Rigal
Nagy Saba El-Rigal
SASamira N. Al-Ghamdi
Samira N. Al-Ghamdi
Jalloul BouajilaJalloul Bouajila
Jalloul Bouajila

1 January 2020 in Toxicology Reports
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Journal Article
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FEFarouk K. El-Baz
Farouk K. El-Baz
HAHanan F. Aly
Hanan F. Aly
Howaida Ibrahim Abd-AllaHowaida Ibrahim Abd-Alla
Howaida Ibrahim Abd-Alla
The carotenoid rich fraction of microalgae Dunaliella salina (crf-DS) have been receiving great attention, due to they abilities to protect and improve various disorders. The objective of this study is to explore the therapeutic efficiency of crf-DS on obesity-assciated cardiac dysfunction in the high-fat diet (HFD) treated rats. These rats were orally administered with crf-DS (150 mg /kg body weight), for six consecutive weeks in comparison with reference drug(orlistat). Specific cardiac biomarkers were examined including; adiponectin, plasminogen activator inhibitor (PAI-1), glucagon, troponin-I (cTnI). The cell adhesion molecules (VCAM and ICAM), C-reactive protein (CRP), collagen type II (Col II), collagen alpha-1 (III) chain (Col3A1), lipoxygenase activity (LOX), as well as histopathological examination of cardiac tissue were investigated. Results indicated a significant reduction(P ≤ 0.05) in adiponectin and glucagon levels in serum of obese rats. However, cTnI, PAI-1, cell adhesion molecules, CRP, Col II, and Col3A1 and LOX levels declared marked increase. Histopathological examination of cardiac tissue showed fibrosis with severe congestion in the myocardial blood vessels. On the other hand, rats medicated with a crf-DS demonstrated noticeable ameliorating effect in all the measured parameters. Beside, myocardial tissue of obese rats showed no alteration. Hence, It could be concluded that, oral supplementation with crf-DS is able to attenuate cardiac dysfunction in obese rats. Further extended work is needed to exploit, the possible application of D. salina as nutraceuticals and food additives.