The invention relates to secretions of marine
halomonas, an extraction method of the secretions and the application of the secretions. The extraction method comprises the following steps: preparing a culture medium according to a formula of 5 g of
yeast powder, 10 g of
tryptone and 1L of
seawater, and sterilizing the culture medium for 15-20 minutes at the temperature of 121 DEG C; inoculating the marine
halomonas into the culture medium under aseptic conditions, culturing the culture medium inoculated with the marine
halomonas for 10-15 days at the constant temperature of 25-30 DEG C on a backward rotating shaking table at the speed of 120-150 rpm, performing
filtration with a film of 0.22-0.45 micrometers, and performing sterilization so as to obtain bacterial
exudate supernatant; vacuum freezing and
drying a filtrate, performing extraction through a pure
acetic acid, and performing
filtration and
desalination through
filter paper; volatilizing the
acetic acid of the obtained filtrate so as to obtain coarse substances of the secretions of the marine halomonas. The secretions disclosed by the invention can be used for governing red tides, and have the effect of restraining dinoflagellates like Alexandrium tamarenses, prorocentrum donghaiense and Karenia mikimotoi of the red tides. According to the invention, the culture conditions are simple, products do not need to be refined, only the
filtration is needed for removing thalli, and the secretions have a good effect of restraining the dinoflagellates of the red tides.