as well as from bacteria, fungi, and sponges (Dakhama et al., 1993). Our
research represents the first evidence of inhibitory properties of extracts from plants of the
family Papaveraceae against green algae, cyanobacteria, daphnias, and duckweed. Plants of
the family Papaveraceae contain a number of biologically active compounds, including
alkaloids (of which more than thirty have been previously identified). Sanguinarine and
chelerythrine exhibit strong antimicrobial activities via various biochemical processes
(Schmeller et al., 1997).