Structure-Antifungal Activity Relationships among Volatile C6 and C9 Aliphatic Aldehydes, Ketones, and Alcohols

Abstract

Antifungal potentials of volatile oxygenated alkyl compounds were determined by bioassay of Alternaria alternata germ tube growth. Compounds were naturally occurring lipoxygenase enzyme system products or related to them chemically. Results were based on headspace concentrations of test compounds.Among six-and nine-carbon aldehydes and ketones related to hexanal, nonanal, 3-hexanone, and 2-nonanone, respectively, the presence of an a,/3-unsaturated bond adjacent to the carbonyl moiety generally enhanced antifungal activity. Among six-carbon alcohols related to 1-hexanol, however, an a,d-unsaturated bond enhanced antifungal activity only slightly. Abundant, naturally occurring (E)-2-hexenal that higher plants emit as a response to wounding tested negatively for mutagenicity; a volatile compound modification of the Ames test with several strains of Salmonella typhimurium was used.

Biochemistry of Plant Volatiles

“…That is, they attract arthropods that prey upon or parasitize herbivores, thus minimizing further damage to plant tissue (Pare and Tumlinson, 1999;Dicke and Van Loon, 2000). In some cases, herbivore-induced volatiles may also act as direct defenses, repelling (DeMoraes et al, 2001;Kessler and Baldwin, 2001) or intoxicating (Vancanneyt et al, 2001) herbivores and pathogens (Andersen et al, 1994). The possibility that these substances also act in plant-plant communication has been discussed (Arimura et al, 2000;Dicke and Bruin, 2001;Engelberth et al, 2004).…”

Dynamics of pheromone production and communication in the mountain pine beetle, Dendroctonus ponderosae Hopkins, and the pine engraver, Ips pini (Say) (Coleoptera: Scolytidae)

“…), the rus t y grain beetle, Cryptolestes ferrugineus (Stephens), the flat grain beetle, C. pusillus (Schonherr) and the tropical bont tick, Amblyomma variegaturn F. (Pierce et al 1990;Mushobozy et al 1993;Turker et al 1993;Steullet and Guerin 1994;Torto et al 1996;Assad et al 1997;Quiroz and Niemeyer 1998). Nonanal in the volatiles of plants acts as an allelochernic that inhibits seed germination (Bradow and Connick 1990) and probably serves in defence against pathogens and phytophagous insects due to its antifungal properties (Andersen et al 1994) as well as cytotoxic and genotoxic effects (Eck1 et al 1993;Martelli et al 1994). The effect of nonanal in decreasing polymerisation of brain microtubular protein (Miglietta et al 1991), possibly renders it extremely toxic to I. pini which inhabits dead trees where toxic volatiles would be relatively low.…”

Anatomía microscópica y metabolitos secundarios volátiles en tres estadios del desarrollo de las inflorescencias de Lantana camara (Verbenaceae)

“…Una de estas funciones es aumentar la tolerancia de la fotosíntesis a las temperaturas altas, estabilizando las membranas tilacoidales (Sharkey et al 2001) o controlando las especies con oxígeno reactivo (Loreto & Velikova 2001). Se ha discutido también la posibilidad de que estas substancias actúen en la comunicación planta-planta (Arimura et al 2000, Dicke & Bruin 2001, Engelberth et al 2004, además de minimizar el daño extenso de los tejidos (Dicke & Van Loon 2000) y actuar como repelentes de los herbívoros y patógenos (Andersen et al 1994, De Moraes et al 2001, Kessler & Baldwin 2001. Estos volátiles inducidos por los herbívoros, podrían tener adicionalmente papeles fisiológicos dentro de la planta, al ser descargados como consecuencia de su volatilidad y solubilidad desde la membrana.…”