An extract of an herbal composition comprising at least two different dried plants useful as antimicrobial and/or antibiofilm agent in the treatment or prevention of microbial infections caused by bacteria, such as for example Escherichia, Klebsiella, Listeria, Pseudomonas, Salmonella, Streptococcus or Staphylococcus, or by fungi, such as for example is herein described. It has been found that in such extract, the active ingredients exert their biological effects in a synergistic manner. The extract may constitute the active ingredient of a food supplement, a nutraceutical, pharmaceutical or cosmetic composition or a functional food or a food additive. A process for preparing said extract is also described here.
