Chitin, Chitosan and Its Derivatives: Antimicrobials and/or Mitigators of Water

Antimicrobial resistance (AMR) is a major global health problem, exacerbated by the excessive and inappropriate use of antibiotics in human medicine, animal care and agriculture. Therefore, new strategies and compounds are needed to overcome this issue. In this view, it may be appropriate to reconsider existing biomaterials to alleviate antibiotic overuse. Chitin, a naturally abundant amino mucopolysaccharide, is a poly-β-1, 4-N-acetylglucosamine (GlcNAc). It is a white, hard, inelastic, nitrogenous polysaccharide and the major source of surface pollution in coastal areas. Chitosan derives from the partial N-deacetylation of chitin and originates from the shells of crustaceans and the fungi cell walls. It is a nontoxic natural antimicrobial polymer approved by GRAS (Generally Recognized as Safe by the United States Food and Drug Administration). Chitin and chitosan, as non-toxic biopolymers, are useful compounds for wastewater treatment to remove pollutants, such as pharmaceuticals, heavy metals and dyes. The described features make these biopolymers intriguing compounds to be investigated for their application as antibacterials.