DYNAMICS OF ANTIBACTERIAL ACTIVITY IN 3 SPECIES OF CARIBBEAN MARINE-ALGAE AS A FUNCTION OF HABITAT AND LIFE-HISTORY

Antibacterial activity of lipid extracts from three species of Caribbe an marine algae, Spyridia filamentosa, S. hypnoides and Wrangelia bicu spidata was evaluated monthly for one year. Activities were tested for whole plant extracts and TLC-separable zones. Whole plant extracts de monstrated monthly variability in activity with respect to both habita t and life history phase in addition to periods of similarity. No cons istency was seen regarding activity against different microorganisms. TLC analyses of the extracts led to the identification of twenty-seven chromatographically distinct regions (TLC zones) each from both S. fi lamentosa and S. hypnoides and twenty-five from W. bicuspidata, which demonstrated antimicrobial activity. Between these species, twenty-one active TLC zones appeared to be shared based on their similar chromat ographic characteristics. Individual TLC zones also demonstrated varia ble activity throughout the sampling period with respect to habitat an d life history phase as well as periods of similarity. Algal antibiosi s in these species is recognized as being highly complex, involving nu merous chemical compounds, each of which is highly variable in terms o f its presence and/or probable concentration.