Effect of temperature, waters and soil-microbiological activity on the loss of monoterpenes from Tagetes minuta L. fruits

LÓPEZ ML; LAURET CM; ZUNINO MP; DAMBOLENA S; ZYGADLO JA

Otro; SECOND JOINT MEETING OF THE BIOLOGY SOCIETIESFROM ARGENTINA; 2011

Evaporation, leaching and biotransformation by soil microorganisms are known pathways of allelochemicals release. The influence of physico-chemical properties of monoterpenes and soil microbiological activity was evaluated on the monoterpenes loss from the essential oil of Tagetes minuta L. (Asteraceae) fruits. Hydrocarbon monoterpenes were lost faster than oxygenated monoterpenes under the effect of temperature. In addition, the lost of each compound in the oil occurred in a similar fashion than the expected according to their vapour pressures. In another experiment, the leaching of each compound from fruits by water was slightly different according to their solubility values since tagetone, ocimenones (cis-trans) and dihydrotagetone showed an altered order. Finally, soil microbiological activity had a pronounced effect on the content of monoterpenes. Under microbiological active soil treatment fruit material showed decreased contents of monoterpenes, while under sterile soil treatment the contents remained constant. The results suggest that physico-chemical properties and soil microbiological activity are factors influencing the loss of monoterpenes from plant material.Tagetes minuta L. (Asteraceae) fruits. Hydrocarbon monoterpenes were lost faster than oxygenated monoterpenes under the effect of temperature. In addition, the lost of each compound in the oil occurred in a similar fashion than the expected according to their vapour pressures. In another experiment, the leaching of each compound from fruits by water was slightly different according to their solubility values since tagetone, ocimenones (cis-trans) and dihydrotagetone showed an altered order. Finally, soil microbiological activity had a pronounced effect on the content of monoterpenes. Under microbiological active soil treatment fruit material showed decreased contents of monoterpenes, while under sterile soil treatment the contents remained constant. The results suggest that physico-chemical properties and soil microbiological activity are factors influencing the loss of monoterpenes from plant material.cis-trans) and dihydrotagetone showed an altered order. Finally, soil microbiological activity had a pronounced effect on the content of monoterpenes. Under microbiological active soil treatment fruit material showed decreased contents of monoterpenes, while under sterile soil treatment the contents remained constant. The results suggest that physico-chemical properties and soil microbiological activity are factors influencing the loss of monoterpenes from plant material.