Samar Desoukey

Chemical constituents from Chorisia chodatii flowers and their biological activities

From the flowers of Chorisia chodatii Hassl. (family: Bombacaceae), seventeen compounds were isolated and identified, including: two sterols, β-sitosterol (1) and β-sitosterol 3-O-β-D-glucopyranoside (10); two furanoids, 5-hydroxymethyl furfural (3) and (3R,4R,5S)-3,4-dihydroxy-5-methyl-dihydrofuran-2-one (12); two coumarins, scopoletin (8) and aesculetin (9); four phenolic acids and esters, ethyl vanillate (4), vanillic acid (5), protocatechuic acid ethyl ester (6) and p-hydroxy benzoic acid (7); five flavonoids, kaempferol 3-O-β-D-(6″-acetyl)-glucopyranoside (13), kaempferol 3-O-β-D-(6″-E-p-coumaroyl)-glucopyranoside (14), kaempferol 3-O-β-D-glucopyranoside (15), luteolin 7-O-β-D-glucopyranoside (16) and apigenin 7-O-neohesperidoside (17), in addition to mono-octyl phthalate (2) and succinic acid (11). All the isolated metabolites were reported for the first time from this plant, and among them, compounds (3), (4), (6), (7), (12) and (13) were isolated for the first time from family Bombacaceae. Besides, this is the first report for isolation of (2) in a pure form from a natural source. These phytochemical data revealed important chemotaxonomic value and may broaden the use of this plant in future phytotherapy. Moreover, all of the obtained phytocompounds were evaluated for their DPPH free radical scavenging properties and cytotoxic activities against the human lung cancer cell line A549.

Natural Product Potential of the Genus Nocardiopsis

Actinomycetes are a relevant source of novel bioactive compounds. One of the pharmaceutically and biotechnologically important genera that attract natural products research is the genus Nocardiopsis, mainly for its ability to produce a wide variety of secondary metabolites accounting for its wide range of biological activities. This review covers the literature from January 2015 until February 2018 making a complete survey of all the compounds that were isolated from the genus Nocardiopsis, their biological activities, and natural sources, whenever applicable.

New Cytotoxic Cyclic Peptide from the Marine Sponge-Associated Nocardiopsis sp. UR67

A new cyclic hexapeptide, nocardiotide A (1), together with three known compounds—tryptophan (2), kynurenic acid (3), and 4-amino-3-methoxy benzoic acid (4)—were isolated and identified from the broth culture of Nocardiopsis sp. UR67 strain associated with the marine sponge Callyspongia sp. from the Red Sea. The structure elucidation of the isolated compounds were determined based on detailed spectroscopic data including 1D and 2D nuclear magnetic resonance (NMR) experimental analyses in combination with high resolution electrospray ionization mass spectrometry (HR-ESI-MS), while the absolute stereochemistry of all amino acids components of nocardiotide A (1) was deduced using Marfey’s method. Additionally, ten known metabolites were dereplicated using HR-ESI-MS analysis. Nocardiotide A (1) displayed significant cytotoxic effects towards the murine CT26 colon carcinoma, human HeLa cervix carcinoma, and human MM.1S multiple myeloma cell lines. The results obtained revealed sponge-associated Nocardiopsis as a substantial source of lead natural products with pronounced pharmacological activities.