Methods of inhibiting cyanobacteria growth by administering gramine derivatives

#1. Field of the Invention

#This invention relates to methods of inhibiting growth of cyanobacteria bloom in freshwater environments by administering synthetic gramine compounds. The methods can be used to treat cyanobacteria in ponds, reservoirs, pools, tanks, lakes, and other fresh water environments.

#Cyanobacteria, also known as blue green algae, can grow in freshwater environments and give the water a greenish and murky appearance. The large scale growth of cyanobacteria in freshwater is called algae bloom, which stresses freshwater environments. Algae blooms can decrease the dissolved oxygen level in the water, therefore stressing the fish and other marine organism populations. Moreover, algae blooms can produce significant amounts of natural toxins that poison the environment. Some cyanobacteria produce hepatotoxin or neurotoxin or both. These toxins irritate the skin and can lead to gastrointestinal inflammation if ingested. In many case, uncontrolled algae blooms kill the fish and other marine organism populations inhabiting the body of water.

#FIG. 1a shows a chemical synthesis process diagram for 5,6-dichlorogramine.

#FIG. 1b shows a chemical synthesis process diagram for 5,6,7-trichlorogamine.

#FIG. 2 is a table showing the effects of various gramine compounds on M. Aeruginosa growth as shown by photographs of petri dishes.

#The present invention discusses utilizing two synthetic gramine compounds, 5,6-dichlorogramine and 5,6,7-trichlorogramine, to inhibit growth of toxic bloom algae caused by Microcystis aeruginosa in freshwater environments. The 5,6-dichlorogramine and 5,6,7-trichlorogramine may each act as an algaestatic agent to inhibit the growth of the algae.

#Gramines are compounds that are naturally occurring in plants and may be synthetically created in laboratories. Gramines are compounds that have the following general structure:

#In some plants, gramines may be present as naturally occurring indole alkaloids that may play a defensive role by being toxic to many organisms. The 5,6-dichlorogramine compound is a synthetic compound that has this structure: