MERCURY-INDUCED CHANGES IN GLUTATHIONE CONTENT OF A GREEN-ALGA, COSMARIUM-CONSPERSUM

Sublethal concentrations of mercuric chloride have caused significant variations in different forms of glutathione in a green alga, Cosmariu m conspersum var. rotundatum f. intermedia. The total glutathione cont ent increased with an increase in mercury concentration and duration o f exposure. There was a significant decline in cellular concentrations of reduced glutathione (GSH) and an increase in oxidised glutathione concentrations following mercury treatment. It is suggested that the r eduction in GSH concentration may be due to its involvement in the syn thesis of phytochelatins which may detoxify the heavy metals.