Fungitoxic activity of some cytochalasins and their derivatives on Phytophthora species

• Published in: Natural toxins Vol. 5; no. 6; p. 228
• Main Authors: Evidente, A, Cristinzio, G, Capasso, R, Andolfi, A
• Format: Journal Article
• Language: English
• Published: United States 1997
• Subjects: CITOCATALASINA; CITOCHATALASANE; CYTOCHALASINS; Cytochalasins - chemistry; Cytochalasins - toxicity; ESPECE; ESPECIES; PHYTOPHTHORA; Phytophthora - drug effects; SPECIES; Species Specificity; Spectrum Analysis; Structure-Activity Relationship; TOXICIDAD; TOXICITE; TOXICITY
• ISSN: 1056-9014; 1522-7189
• DOI: 10.1002/(SICI)1522-7189(1997)5:6<228::AID-NT2>3.0.CO;2-M

The activity of cytochalasin B was tested on 8 Phytophthora species, while the same toxin, some of its derivatives and natural analogues, namely cytochalasin F and deoxaphomin, were assayed at 2 x 10(-5) - 2 x 10(-4) M on the most sensitive species, P. cactorum. A significant inhibitory activity on P. cactorum was shown by cytochalasin B, its 7-monoacetyl derivative, and deoxaphomin. The hydroxy group at C-20 and the conformational freedom of the macrocyclic ring proved to be important structural features for this activity. The 7-hydroxy group at C-7 appeared to have no influence on this toxicity, while a size reduction associated with the carbocyclic nature of the macrocycle seems to lightly increase the activity. The 7-O-acetylcytochalasin B showed selective toxic activity on P. cactorum at the tested concentration, thus suggesting a possible use as a fungicide for this compound.