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

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

san juan

Congreso; SECOND JOINT MEETING OF THE BIOLOGY SOCIETIES FROM ARGENTINA; 2011

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