John Refaat Fahim

Ceiba (syn. Chorisia) trees have attracted multifaceted attention not only due to their ornamental and economic value but also for their remarkable metabolic diversity and therapeutic properties. In view of that, this work explores the chemical composition of Ceiba chodatii Hassl. and its biological potential. Overall, GC–MS-based analysis of the lipoidal constituents of C. chodatii flowers revealed the presence of diverse classes of metabolites that were dominated by long-chain aliphatic esters (77.016%), ketones (6.396%), aliphatic hydrocarbons (5.757%), fatty alcohols (3.718%), aromatic acid esters (2.794%), alkylamides (1.58%), aldehydes (1.035%), aromatic hydrocarbons (0.31%), and ethers (0.29%). In addition, repeated chromatographic fractionation of different fractions of the total alcoholic extract of the flowers afforded 13 metabolites of varied structural types, including fatty esters and alcohols, phytosterols, monoglycerides, furanoids, and flavonoid glycosides. Structures of the obtained compounds were determined by different spectroscopic techniques, such as 1H- and 13C-NMR, APT, DEPT, and EI–MS analyses. Noteworthily, a wide range of the metabolites identified herein using different analytical approaches were described for the first time in the plant species under study or in those belonging to the genus Ceiba. Finally, the total extract and different fractions of C. chodatii flowers as well as the isolated flavonoids showed weak anti-infective potential against a group of human pathogens at concentration ranges up to 200 and 20 µg/mL, respectively. In contrast, the total extract and different fractions of the flowers exerted mild to moderate anti-proliferative activities against MDA-MB-468 cells, with IC₅₀ in the range of 21.69–47.60 μg/mL.

Chorisia (syn. Ceiba) is a genus of approximately 20 species of large, perennial, and deciduous trees within the plant family Bombacaceae, with common geographical distribution throughout the subtropical and tropical regions, especially South America. Besides their well-known ornamental and economic value, members of the genus Chorisia have found applications as medicinal plant species thanks to their assortments of bioactive phytoconstituents. To date, about 273 structurally varied metabolites have been described from different plant parts of Chorisia plants using various chromatographic and spectroscopic techniques, which mainly included flavonoids, anthocyanins, phenolic acids, quinones, terpenoids, and steroids, among others. Moreover, several organic solvent extracts and purified metabolites from Chorisia plants have been tested for their biological potential, such as anti-inflammatory, analgesic, antipyretic, antioxidant, hepatoprotective, antiobesity, cytotoxic, antidiabetic, hypolipidemic, antiulcerogenic, and antimicrobial properties. In of view of that, the current work provides an overview on different phytochemicals reported from the genus Chorisia as well as various biological and toxicological studies conducted so far on these plants, along with future research perspectives that might help expand their phytotherapeutic applications.

Sixteen chemically varied metabolites were isolated from the bulbs of Hippeastrum vittatum (L'Her.) Herb., including eight flavonoids [3'-methyl isoliquiritigenin (2), 7-hydroxyflavan (8), 7-hydroxyflavanone (9), 7-hydroxyflavan-3-ol (10), 7-methoxy-3',4'-methylenedioxyflavan-3-ol (11), 7-hydroxy-3',4'-methylenedioxy flavan (12), 2',4'-dihydroxy-3'-methyl-3,4-methylenedioxychalcone (13), and isoliquiritigenin (14)], four acetophenones [2,6-dimethoxy-4-hydroxyacetophenone (3), 2,4-dihydroxyacetophenone (4), 2,4-dihydroxy-6-methoxy-3-methylacetophenone (6), and 2,4,6-trimethoxyacetophenone (7)], two alkaloids [lycorine (1) and narciprimine (15)], one phenol derivative [p-nitrophenol (5)], and one steroid [β-sitosterol 3-O-β-glucopyranoside (16)]. Their structures were elucidated by combining one- and two-dimensional NMR and ESI-MS techniques and by comparison with the reported literature data and some authentic samples. Except for lycorine (1), the isolated metabolites were obtained herein for the first time from Hippeastrum plants, among which compound 13 was identified as a new chalcone derivative. Additionally, the total phenolic and flavonoid contents of the total ethanol extract and different fractions of the bulbs were determined by the Folin-Ciocalteu and aluminum chloride colorimetric methods, respectively, whereas their antioxidant potential was compared using the phosphomolybdenum and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assays. Finally, the binding affinities of compounds 1-16 to some key target proteins of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), namely, main protease (M^pro), papain-like protease (PLpro), and RNA-dependent RNA polymerase (RdRp), were screened and compared using molecular docking analysis. The possible chemotaxonomic significance of the identified metabolites was also discussed.

Khella (Ammi visnaga (L.) Lam.) and celery (Apium graveolens L.) are two valuable medicinal plant species with a wide-ranging health and therapeutic benefits, including hepatoprotective and antiviral properties. Thus, in this work, the total ethanolic extracts of the roots of the aforementioned species were studied for their antiviral potential against Hepatitis C virus (HCV) using the in vitro luciferase assay. The obtained data demonstrated the noteworthy inhibitory activity of khella roots against HCV (IC50= 9.5 µg/ml), while no noticeable inhibition was shown by celery roots. Besides, three phytosterols (I‒III) and one furanochromone (IV), with previously reported antiviral properties, were isolated and identified from khella roots for the first time. These data could pave the way towards further phytochemical and biological investigation of such medicinal roots as potential sources of natural anti-HCV agents.