Publications by authors named "Nagib Qarah"

Background: Naringenin (NA) is a natural flavonoid used in the formulation of a wide range of pharmaceutical, fragrance, and cosmetic products. In this research, NA was extracted from using an environmentally friendly, high efficiency extraction method: an ultrasound-assisted extraction with deep eutectic solvents (UAE-DES).

Methods: Six natural deep eutectic solvent systems were tested.

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Isoquercetin (ISQ) is reported to be a powerful antioxidant with extremely high bioavailability and structural stability compared to aglycone quercetin. Despite this, it is not well studied due to the limited methods for its extraction. With the growing interest in the research and analysis of ISQ-rich herbs, there is a need to optimize an efficient and rapid method for their extraction.

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Ethnopharmacological Relevance: The genus Ziziphus (Rhamnaceae) contains 58 accepted species that are extensively used by local people and medicinal practitioners in arid and semi-arid regions for the treatment of diarrhoea, dysentery, cholera, diabetic, hypertension, inflammation, intestinal spasm, liver, malaria and other diseases. Aims of this review: This review article documents and critically assesses, for the first time; up to date categorized information about botanical traits, distribution, traditional uses, phytochemistry, pharmacological and toxicological effects of Ziziphus species.

Methods: Information was collected systematically from electronic scientific databases including Google Scholar, Science Direct, PubMed, Web of Science, ACS Publications, Elsevier, SciFinder, Wiley Online Library and CNKI, as well as other literature sources (e.

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Two simple methods are described for the determination of ethionamide (ETM) in bulk drug and tablets using cerium (IV) sulphate as the oxidimetric agent. In both methods, the sample solution is treated with a measured excess of cerium (IV) solution in HSO medium, and after a fixed standing time, the residual oxidant is determined either by back titration with standard iron (II) solution to a ferroin end point in titrimetry or by reacting with o-dianisidine followed by measurement of the absorbance of the orange-red coloured product at 470 nm in spectrophotometry. In titrimetry, the reaction proceeded with a stoichiometry of 1 : 2 (ETM : Ce (IV)) and the amount of cerium (IV) consumed by ETM was related to the latter's amount, and the method was applicable over 1.

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