Biomedical subjects

L Gunthorpe

Publications and source records attributed to L Gunthorpe.

3 recordsLinked to original sources

PubMed1990

Toxic exudate from the hard coral Goniopora tenuidens.

Ten colonies of Goniopora tenuidens were placed individually in sea water for 1 hr after which time the sea water was assayed using toxicity to another hard coral Galaxea fascicularis and to other colonies of G. tenuidens. Sea water from eight of the 10 colonies assayed was toxic to at least one of the bioassay organisms. Thus, G. tenuidens can extrude biologically active substances that adversely affect potential competitors, both interspecific and conspecific.

Animals↗

PubMed1990

Widespread but variable toxicity in scleractinian corals.

Aqueous and/or aqueous ethanol extracts were made of 58 scleractinian species from 11 families, collected from Heron Island, Great Barrier Reef. At least one extract from each of 53 species (91%) exhibited activity against at least one bioassay system. Extracts from at least one colony of each of 41 species of the 58 tested were toxic to mice when injected i.p. Cytolysis of sheep red blood cells was produced by extracts from at least one colony of each of 49 species of the 57 species tested and antibacterial activity was present in extracts from at least one colony of each of 37 species of the 55 tested. Only four species from 45 species assayed yielded extracts toxic to mosquito fish. This is the first report of bioactivity in extracts of 46 species of coral and the first report of bioactivity of extracts of corals from the families Mussidae, Merulinidae, Siderastreidae, Oculinidae and Dendrophylliidae. Variable results on a particular bioassay exhibited by extracts from different colonies of a given species were analysed by the Generalized Linear Interactive Modelling system (GLIM). Toxicity to mice, cytolytic and antimicrobial activity are not significantly correlated with each other. No model could be generated to explain the variation in the incidence of cytolytic activity nor of antimicrobial activity. However antimicrobial activity varied significantly between collection trips and was negatively associated with the presence of immature gonads in the colonies. The model predicts that toxicity to mice will be higher in extracts collected when average maximum monthly air temperature is high.

Animals↗

PubMed1990

Intracolonial variation in toxicity in scleractinian corals.

Single colonies of the scleractinian corals Lobophyllia corymbosa, Favites abdita, Favia matthaii, Favia stelligera, Platygyra daedalea, Leptoria phrygia, Cyphastrea serailia, Hydnophora exesa and Astreopora myriophthalma were permanently marked with buoys on the reef flat at Heron Island. Great Barrier Reef. Portions of colonies were removed up to seven times at intervals of two or three months. Aqueous extracts of the colony portions were assayed using six bioassay regimes namely, toxicity to mice, toxicity to a coral and a hydroid, cytolytic activity on sheep erythrocytes and sea urchin ova and for antimicrobial activity on eight bacterial species. The incidence of one type of bioactivity in an extract was not correlated with the incidence of any other type of activity in that extract. Although each coral colony provided extracts that affected at least two of the bioassay systems, different activity profiles were obtained from successive extracts of each colony. Thus there is a temporal component to the idiosyncratic nature of bioactivity within a given colony of scleractinian coral.

Animals↗