Cytotoxic Alkaloids Derived from Marine Sponges: A Comprehensive Review

Marine sponges (porifera) have proved to be a prolific source of unique bioactive secondary metabolites, among which the alkaloids occupy a special place in terms of unprecedented structures and outstanding biological activities. Identification of active cytotoxic alkaloids extracted from marine animals, particularly sponges, is an important strive, due to lack of knowledge on traditional experiential and ethnopharmacology investigations. In this report, a comprehensive survey of demospongian bioactive alkaloids in the range 1987-2020 had been performed with a special emphasis on the potent cytotoxic activity. Different resources and databases had been investigated, including Scifinder (database for the chemical literature) CAS (Chemical Abstract Service) search, web of science, Marin Lit (marine natural products research) database. More than 230 representatives of different classes of alkaloids had been reviewed and classified, different genera belonging to the phylum porifera had been shown to be a prolific source of alkaloidal molecules, including Agelas sp., Suberea sp., Mycale sp., Haliclona sp., Epipolasis sp., Monanchora sp., Crambe sp., Reniera sp., and Xestospongia sp., among others. The sufficient production of alkaloids derived from sponges is a prosperous approach that requires more attention in future studies to consider the constraints regarding the supply of drugs, attained from marine organisms.

The effect of Punica granatum L. flower extract on post-surgical peritoneal adhesions in a rat model

OBJECTIVE

Peritoneal adhesions may develop after every abdominopelvic surgery. Many agents and technical modifications have been investigated to minimize adhesions. Punica granatum (pomegranate) flower has some anti-inflammatory and antioxidative effects that would reduce the formation of peritoneal adhesions. In the present study, the effects of different doses of oral Punica granatum flower extract on postoperative peritoneal adhesions were evaluated in a rat model.

STUDY DESIGN

Thirty-two female Wistar rats were divided into four groups: one control group (CG) and three experimental groups, treated with 100 (EG100), 200 (EG200), and 400 (EG400) mg/kg/day Punica granatum extract orally for eight days. Induction of peritoneal adhesions was done in all groups using the same method. Two weeks after the first surgery, all rats re-operated and adhesions were evaluated via both macroscopic and microscopic changes.

RESULTS

We observed that rats in the control group had statistically higher adhesion area and more severe adhesions when compared to all experimental groups. Besides, those in the EG-400 group had a significantly lower rate of foreign body reaction in serosal layer when compared to the other three study groups. Other microscopic findings were comparable between the four groups.

CONCLUSION

Administration of the oral Punica granatum flower extract was associated with a decreased quantity and quality of the adhesions in the animal model of rat in this study. This therapy might be an effective and safe strategy to reduce intraperitoneal adhesion after abdominal surgeries in animal models.

Phytochemical and biological evaluation of some Sargassum species from Persian Gulf

Sea algae are widely consumed in the world. There are several seaweeds including brown algae which are authorized for human consumption. These plants contain important phytochemical constituents and have various potential biological activities. The present study investigated the presence of phytochemical constituents and total phenolic quantity of the seaweeds Sargassum angustifolium, Sargassum oligocystum and Sargassum boveanum. Cytotoxicity of seaweeds was tested against HT-29, HeLa and MCF-7 cell lines. Antioxidant potential of these 3 Sargassum species was also analyzed. Cytotoxicity was characterized by IC50 of human cancer cell lines using sulforhodamine assay. Antioxidant activities were evaluated using 2,2-diphenyl-1- picrylhydrazil. The analysis revealed that tannins, saponins, sterols and triterpenes were the most abundant compounds in these Sargassum species while cyanogenic and cardiac glycosides were the least ones. Sargassum angustifolium had the highest content of total phenolics (0.061 mg/g) and showed the highest antioxidant activity (IC50 = 0.231). Cytotoxic results showed that all species could inhibit cell growth effectively, especially MCF-7 cell line (IC50 = 67.3, 56.9, 60.4 for S. oligocystum, S. angustifolium and S. boveanum respectively). Considerable phytochemicals and moderate cytotoxic activity of S. angustifolium, S. oligocystum and S. boveanum make them appropriate candidate for further studies and identification of their bioactive principles.