 Olvan polysaccharides extracted from Ulvarigida have been shown to possess strong anti-cancer properties in both in vitro and in vivo studies. In vitro experiments suggest that these polysaccharides are effective against several types of cancer cells, including human fibroblasts, immortalized human keratinocytes, a human leukemia cell line, a human malignant melanoma cell line, and a colon cancer cell line. And vivo tests on zebrafish embryos indicate that olvan can cause significant growth retardation when administered at high doses, but that lower dosages do not appear to cause any harmful effects. These results suggest that olvan may be a viable option for treating certain types of cancer. This article was authored by Jorge García Marquez, Bruna Rodriguez-Morera, P.A. Dodd-Valverdeguian, and others.