polyglycerol anti - microbial agents and compositions are provided . the agents are effective against a variety of pathogens including fungi , gram positive bacteria and gram negative bacteria yet are expected to have low human toxicity due in part to their polymeric nature . applications for the polyglycerol anti - microbial agents and compositions include those involving human and plant contact , such as cosmetics , hair care products , textiles and plant protections , as well as in applications with much less human contact , such as plastics , coatings , wood , paper and other materials of construction .