Comparative studies of allergenic extracts prepared from freshly collected, dried, or dried and defatted pollen

Fresh pollen samples of Parietaria judaica, Betula pubescens, Dactylis glomerata and Olea europaea were collected and aliquot portions of these pollens were stored after drying in hot air, while other portions were dried and then defatted with diethylether. The different pollen materials were extracted with aqueous media to obtain the non-dialyzable allergenic protein constituents. Review of the production data, together with comparative analyses of the UV-absorption spectra and of IgE binding potencies did not reveal appreciable differences in allergen composition among extracts of fresh, dried, or dried and defatted pollen materials. However, microscopic examination showed the fresh pollen to be no longer viable.