In vitro evaluation of antifungal activity of aqueous extract of lemon grass (Cymbopogon citrates) against pathogenic fungi Saprolegnia parasitica isolated from endangered cold water fish Tor putitora.

An attempt was made to evaluate the antifungal activity of aqueous extract of Cymbopogon citrates for controlling Saprolegnia parasitica (in vitro) isolated from endangered fish Tor putitora. Sterilized aqueous extract of Cymbopogon citrates at different concentrations (5%, 8% and 10% w/v) was tested against the mycelial mass of the Saprolegnia parasitica for three different time periods (20 min., 40 min., and 60 min.) and colony diameter of Saprolegnia fungus was measured. Bacteria free pure culture of the test fungus was maintained on SDA (Sabouroud's Dextrose agar). Results revealed that the aqueous extract of C. citrates possess high degree of antifungal activities against the test pathogen. Accordingly the MIC (minimum inhibitory concentration) was determined as 5% w/v at 20 minute exposure time for the extract.