ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Antifungal activity of chitosan on post-harvest pathogens: induction of morphological and cytological alterations in Rhizopus stolonifer.

El-Ghaouth, A.; Arul, J.; Asselin, A.; Benhamou, N.;

Mycological Research Year: 1992 Vol: 96 Issue: 9 Pages: 769-779 Ref: 35 ref.

1992

บทคัดย่อ

The effect of chitosan preparations with different levels of deacetylation and other polyanions on the growth of postharvest pathogens was investigated. Chitosan markedly reduced the radial growth of all the fungi tested, with a greater effect at higher concn. Chitosan was more effective than N,O-carboxymethylchitosan, polygalacturonate or D-glucosamine, and its inhibitory activity appeared to increase with the level of deacetylation. In addition to inducing cellular leakage of amino acids and proteins in Botrytis cinerea and R. stolonifer, chitosan also caused morphological changes in R. stolonifer. The ultrastructural study showed that chitosan caused deep erosion of the cell wall as well as increasing the cell-wall thickness. Although chitosan treatment did not affect chitin distribution in R. stolonifer walls, it stimulated the activity of chitin deacetylase, an enzyme involved in the biosynthesis of chitosan. This may well upset the balance between biosynthesis turnover of chitin, thereby rendering the cell wall more viscoelastic.