Bioactivity-guided isolation supported by LC-HRESIMS metabolic profiling led to the isolation of two new compounds, a ceramide, stylissamide A (1), and a cerebroside, stylissoside A (2), from the methanol extract of the Red Sea sponge Stylissa carteri. Structure elucidation was achieved using spectroscopic techniques, including 1D and 2D NMR and HRMS. The bioactive extract’s metabolomic profiling showed the existence of various secondary metabolites, mainly oleanane-type saponins, phenolic diterpenes, and lupane triterpenes. The in vitro cytotoxic activity of the isolated compounds was tested against two human cancer cell lines, MCF-7 and HepG2. Both compounds, 1 and 2, displayed strong cytotoxicity against the MCF-7 cell line, with IC₅₀ values at 21.1 ± 0.17 µM and 27.5 ± 0.18 µM, respectively. They likewise showed a promising activity against HepG2 with IC₅₀ at 36.8 ± 0.16 µM for 1 and IC₅₀ 30.5 ± 0.23 µM for 2 compared to the standard drug cisplatin. Molecular docking experiments showed that 1 and 2 displayed high affinity to the SET protein and to inhibitor 2 of protein phosphatase 2A (I2PP2A), which could be a possible mechanism for their cytotoxic activity. This paper spreads light on the role of these metabolites in holding fouling organisms away from the outer surface of the sponge, and the potential use of these defensive molecules in the production of novel anticancer agents.

Cleome amblyocarpa Barr. and Murb. from the family Cleomaceae is used in folk medicine as it has analgesic, anti-inflammatory, antibacterial and antioxidant activities.

Crude or semi-purified extracts of plants can play a significant role as antitumor agents. They were used as stabilizing and reducing agents in the preparation of silver nanoparticles (AgNPs) that allows these particles to have more efficient cytotoxic activity. In the current study, the extract of Marrubium alysson L., a plant of common occurrence in Egypt was used to synthesize AgNPs for the first time, where comparison of anticancer activity of crude and phenolic extracts with the AgNPs were extensively studied against cancer cell lines PC-3 and HCT-116. Interestingly, AgNPs of the crude extract exhibited promising cytotoxicity with IC₅₀ values of 10.4 and 16.3 μg/ml, while AgNPs of the phenolic extract exhibited very potent cytotoxicity with IC₅₀ values of 2.66 and 1.34 μg/ml compared to Doxorubicin (as a standard reference drug) that exhibited IC₅₀ values of 5.13 and 4.36 μg/ml, respectively against the tested cells. Additionally, AgNPs of the phenolic extract induced apoptosis in HCT-116 with a higher ratio than in PC-3 cells. It induced apoptosis in PC-3 cells by 79.3-fold change, while it induced total colon apoptotic cell death by 228.3-fold change compared to untreated control. Finally, the apoptotic activity of AgNPs of the phenolic extract in the treated PC-3 and HCT-116 cells was confirmed using RT-PCR. As a result, AgNPs of the phenolic extract could be considered a promising anticancer candidate through apoptosis-induction.Communicated by Ramaswamy H. Sarma.

Encouraged by new drug developments, the present research was investigated on extracts of Red Sea marine resources all from Egypt. Extracts from three sponges namely Spheciospongia vagabunda (SAA-14), Negombata corticata (SAA-8) and Negombata magnifica (SAA-64) in addition to two soft corals Sarcophyton glaucum (SAA-33) and Sarcophyton auritum (SAA-43) were found to display high potential against HepG2 (liver cancer cell line) and MCF-7 (breast cancer cell line). Cytotoxic potential activities of these five extracts were measured by the Sulpho-Rhodamine-B (SRB) assay. The anticancer activity of SAA-8, SAA-14,SAA-33, SAA-43 and SAA-64 was significantly enhanced in the liver cancer cell line with the values ranged from16.3 to 19.3μg/ml and in the breast cancer cell line with concentrations of 24.7, 19.7, 18.7,21.1and 25.8μg/ml, respectively compared to doxorubicin as positive control. Negom batacorticataand Sarcophyton auritum based extracts exhibited promising antifungal activity against fungi of genus Candida, Cryptococcus and Aspergillus, moreover, the five extracts revealed antiprotozoal and antimicrobial activity after in vitro assays. Also Negombata corticata has good antituberculosis, antimalarial and antilieshmanial potentials.