Improved Antitumoral Activity of Extracts Derived from Cultured Penicillus dumetosus

Purpose: Extracts of the green alga, Penicillus dumetosus, have shown antiproliferative activity against several cancer cell lines. The aim of this study was to evaluate if this activity is modified after cultivation. Methods: P. dumetosus was cultured under different light treatments. After 10, 20 and 30 days, alga samples were collected and their organic extracts prepared. Lipid and phenol contents were evaluated by standardized methods. Antiproliferative activity was assayed in four cancer cell lines (Hep-2, HeLa, SiHa, and KB) while cytotoxic activity was evaluated on a normal cell line (MDCK). Results: The 10-day cultivation organic extract exhibited increased antiproliferative activity compared with the control on human carcinoma nasopharynx (KB) and laryngeal (Hep-2) cell lines. The inhibition of cell growth (IC50) of 20- and 30-day extracts decreased compared with the control, except for KB. This activity was related to induction of apoptosis as evidenced by DNA fragmentation. All the extracts showed low cytotoxicity. Total phenol content in the organic extracts did not change during cultivation; however, polyunsaturated fatty acid content was modified under different light treatments. Conclusion: The 10-day cultivation extract from P. dumetosus culture under conditions described in this study showed increased antiproliferative activity compared with the control and induced apoptosis on SiHa, HeLa, Hep-2 and KB cells.