Bioregulatory and Therapeutic Effects of Blue Green Algae
Author(s): KUMAR K. ; LAKSHMANAN A. ; KANNAIYAN S. ; Indian Journal of Microbiology Indian J. Microbiol 2003, vol. 43, no1, pp. 9-16
Publisher: Association of Microbiologists of India, Hisar, INDE (1961) (Revue
Abstract In recent years, there has been a tremendous increase in the interest in micro algal metabolites. A novel 11-kDa virucidal protein, named cyanovirin- N (CV-N) has been isolated and sequenced from cultures of filamentous blue green alga, Nostoc ellipsosporum. This compound irreversibly inactivated diverse T-lymphocyte-tropic (T-tropic), laboratory adapted strains of HIV type 1, HIV type 2 and simian immunodeficiency virus (SIV). A water based extract of Aphanizomenon flos-aquae containing high concentrations of phycocyanin inhibited the in vitro growth of one out of four tumor cell lines, indicating that at least some tumor cell types may be directly sensitive to killing by phycocyanin. Another fresh water blue-green alga, Phormidium tenue containing several diacyl-glycerol compounds effectively inhibited chemically induced skin tumors in mice. Studies on whole blue green algae in humans, mice, rats, cats and chickens have demonstrated their effect on phagocytosis, NK cell function and inflammation. Blue green algae in general contain a significant amount of carotenoids, namely beta carotene, lycopene and lutein, providing it good antioxidant properties. By their quenching action on reactive oxygen species, antioxidants carry intrinsic anti-inflammatory properties. Macrolides are one of the structural types often seen in Streptomyces-metabolites, and several major antibiotics belong to this class. Macrolides are also produced by blue green algae that include scytophycins from Scytonema sp. and tolytoxin from Tolypothrix conglutinata var. colorata. The coming years may witness some interesting developments in biotechnology of blue green algae which may give a new dimension to the therapeutic utilization of blue green algae.