Quintaquinone, a Merosesquiterpene from the Yellow Sponge Verongula cf. rigida Esper.

A chemical investigation of the sponge Verongula cf. rigida led to the isolation of 13 merosesquiterpenes, among which quintaquinone (2), 5-epi-nakijiquinone L (3), and 3-farnesyl-2-hydroxy-5-methoxyquinone (4) were isolated and reported here for the first time. Particularly, compound 2 is the first member of merosesquiterpenes with a polyketide side chain substituted on C-19. All of the isolated compounds were examined for steroid 5α-reductase inhibitory activity. Cyclospongiaquinone 1 (5) showed a strong activity in the same range as that of standard finasteride.

Physicochemical properties of alpha-mangostin loaded nanomeulsions prepared by ultrasonication technique.

HYPOTHESIS: Alpha-mangostin (AMG) is a natural compound possessing strong antibacterial activity. Because of its poor water solubility, the formulations of AMG usually require high concentrations of solubilizers leading limitation for using in some clinical applications. Thus, the novel formulation of topical nanoemulsion (NE) containing AMG (AMG-NE) with optimal content of the oil phase and surfactants was developed. EXPERIMENTS: AMG was extracted, purified and used as an active ingredient of AMG-NE. Blank NEs (NEs without AMG) with varying in contents of the oil phase and surfactants and AMG-NE were prepared by the ultrasonication technique. They were investigated their physicochemical properties including antibacterial activity against Staphyloccocus aureus and Propionibacterium acnes (which is recently renamed as Cutibacterium acnes). FINDINGS: Blank NEs and AMG-NE had droplet size in a range of nanometer and negative value of zeta potential. The droplet size, polydispersity index and zeta potential of blank NEs were affected by formulation compositions and sonication intensities. AMG could be loaded into a representative Blank NE at a maximum concentration of 0.2% w/w and did not cause significant changes in physicochemical properties. AMG-NE showed the antibacterial activity against Staphyloccocus aureus and Propionibacterium acnes without toxicity to the skin cells. Therefore, AMG-NE had potential for using in a clinical study to investigate its efficacy and safety in patients.

Antiproliferative effects of 12-oxoheteronemin vs heteronemin.

The antiproliferative activities of 12-oxoheteronemin and heteronemin were evaluated in six cancer cell lines and IC50 values ranging from 0.66 to 1.35 microM were obtained. In four of the cell lines, 12-oxoheteronemin and heteronemin were equipotent; however, in two estrogenic receptor-positive cell lines, heteronemin showed a stronger potency. Both compounds had no overt effects on cell cycle distribution in HeLa cells, but did rapidly initiate apoptosis as evidenced by increased sub-G1 populations of cells and caspase-dependent PARP cleavage.

Kabiramides J and K, trisoxazole macrolides from the sponge Pachastrissa nux.

Three trisoxazole macrolides possessing a 30-α,ß-enone moiety, including the known kabiramide G (1) and the new kabiramides J (2) and K (3), were isolated from the sponge Pachastrissa nux, along with the previously reported kabiramides B (4), C (5), and D (6). To date, the enone moiety has been found to associate solely with the trisoxazole macrolides from P. nux. All of the isolated macrolides showed moderate to strong antimalarial and cytotoxic activities, except for 1, which possessed only potent cytotoxicity.