The present invention relates to provide an antimicrobial composition to control the growth of pathogenic bacteria and pathogenic fungi in a host plant. The antimicrobial composition includes a metal salt, polysaccharide and a protease wherein the protease is bound to the metal and the polysaccharide. Further, the present invention also discloses a process to synthesize an antimicrobial composition to control the growth of pathogenic bacteria and pathogenic fungi.