Synthesis and Fungicidal Activity of New N,O-Acyl Chitosan Derivatives

• Published in: Biomacromolecules 2004-03, Vol.5 (2), p.589-595
• Main Authors: Badawy, Mohamed E. I, Rabea, Entsar I, Rogge, Tina M, Stevens, Christian V, Smagghe, Guy, Steurbaut, Walter, Höfte, Monica
• Format: Article
• Language: English
• Subjects: Antifungal Agents - chemical synthesis; Antifungal Agents - pharmacology; Applied sciences; Botrytis - drug effects; Botrytis - growth & development; Chitin - analogs & derivatives; Chitin - chemical synthesis; Chitin - pharmacology; Chitosan; Exact sciences and technology; Magnetic Resonance Spectroscopy; Microbial Sensitivity Tests - methods; Natural polymers; Physicochemistry of polymers; Starch and polysaccharides
• ISSN: 1525-7797; 1526-4602
• DOI: 10.1021/bm0344295

Novel N,O-acyl chitosan (NOAC) derivatives were synthesized to examine their fungicidal activity against the gray mould fungus Botrytis cinerea (Leotiales:  Sclerotiniaceae) and the rice leaf blast fungus Pyricularia oryzae (Teleomorph:  Magnaporth grisea). The fungicidal activity was evaluated by the radial growth bioassay. NOAC derivatives were more active against the two plant pathogens than chitosan itself, and the effect was concentration dependent. Against B. cinerea, 4-chlorobutyryl chitosan (EC50 = 0.043%), decanoyl chitosan (EC50 = 0.044%), cinnamoyl chitosan (EC50 = 0.045%), and p-methoxybenzoyl chitosan (EC50 = 0.050%) were the most active (12−13-fold more active than chitosan). (Un)-substituted benzoyl chitosan derivatives were more active against B. cinerea than most of these with N,O-alkyl derivatives. Against P. oryzae chitosan derivatives with lauroyl, methoxy acetyl, methacryloyl and decanoyl were the most active.