Phenols and Flavonoids in Aleppo Pine Needles as Bioindicators of Air Pollution

International audience ; croses or growth and development disturbances (Im-pens and Delcarte, 1995; Manning et al., 2002), or the The aim of the present study is to assess whether certain ecophysio-occurrence of internal physiological alterations (Ross-logical responses (contents of total phenols, total proanthocyanidins, and total and simple flavonols), in the needles of Aleppo pines (Pinus bach et al., 1999). In the latter case, analysis involves halepensis Mill.) may be valid bioindicators for the assessment of the the measurement of certain chemical compounds con-air quality. Samples were taken at five natural sites polluted by various tained in the plants as revealing a particular environ-pollutants (NO, NO 2 , other NO x , SO 2 , and O 3). The results show a mental state. In particular, the impact of air pollutants decrease in total phenol concentrations with levels of nitrogen oxide is often studied on the basis of experimentation under pollutions (significant negative correlations between the total phenol controlled conditions, each pollutant being generally concentrations and concentrations of NO, NO 2 , and other NO x). Total tested in isolation (Peñ uelas et al., 1996; Rodrigues et flavonoids (total flavonols and proanthocyanidins) are useful bioindi-al., 1996). Studies performed under natural conditions cators for ozone pollution (significant negative correlations between are rare and sometimes only deal with the impact of a total proanthocyanidins and the concentrations of ozone and signifi-single type of pollutant (Karlsson et al., 1995; Oleksyn cant positive correlations between total flavonols and the ozone pollution). Sulfur dioxide pollution is distinguished by low concentrations et al., 1999; Chappelka et al., 1999). However, the valida-in quercetin, isorhamnetin, and kaempferol (significant negative cor-tion of a bioindicator requires the undertaking of experi-relations between these simple flavonols and the concentrations of ments under natural conditions. SO 2). This work confirms the ...