Compositions of Propolis, Myroxylon pereirae Resin, and Colophonium for Patch Testing: Analyses With Gas...

Propolis, Myroxylon pereirae resin (balsam of Peru), and colophonium are complex botanical materials that frequently co-react when patch tested. Detailed knowledge of their compositions may help explain the co-reactivity pattern and identify the haptens responsible for positive patch tests.

To study the compositions of propolis, M. pereirae resin, and colophonium used for patch testing and assess whether they contain identical ingredients.

The ingredients of 3 samples of propolis, 2 of M. pereirae resin and 2 of colophonium used for preparing patch test preparations by Chemotechnique and SmartPractice (brand Allergeaze) were analyzed using gas chromatography-mass spectrometry.

Major ingredients in Brazilian propolis were non-volatile fatty materials; in Chinese propolis tectochrysin, pinostrobin, pinocembrin, and p-vinylguaiacol; in M. pereirae resin benzyl benzoate, benzyl cinnamate and nerolidol; in colophonium Chemotechnique isoabienol, β-caryophyllene, sandaracopimarinal, sandaracopimarinol and longifolene; in colophonium Allergeaze lupeol acetate, longifolene, sandaracopimarinol, abietinal and isoabienol. Only 11 chemicals were present in 2 materials, none in all 3.

Very few identical chemicals were found in propolis, M. pereirae resin, and colophonium. The results do not support the notion that the frequently observed co-reactivity to these complex natural materials can be explained by identical chemicals detected in this study.