Photoreactive substances in homoeopathic mother tinctures: analysis and risk assessment
The identification of photoreactive substances belonging to different classes (furanocoumarins, quinones and naphthodianthrones) was carried out on homoeopathic mother tinctures (MT) using HPLC. The MT selected for analysis were those suspected to contain photoreactive substances according to the literature data. 33 MT were tested for furanocoumarin derivatives. 10 MT contained one or more of the 3 furanocoumarins [psoralen, bergapten (5-MOP) and xanthotoxin (8-MOP)]: Ammi majus, Angelica archangelica, Citrus vulgaris, Citrus bergamia, Dictamnus albus, Ficus carica, Heracleum sphondylium, Bituminaria bituminosa, Ptelea trifoliata and Ruta graveolens. Furanocoumarin derivatives were detected in 6 MT and no furanocoumarin derivatives were found in 17 MT. The average of the total furanocoumarin derivatives content were 0.08% for Ammi majus, 0.07% for Ficus carica and Angelica sylvestris, 0.05% for Ruta graveolens, Angelica archangelica and Angelica pyrenaea, 0.04% for Bituminaria bituminosa. 8 MT were tested for quinonic compounds. 4 MT contained quinonic compounds (juglone and plumbagine) in the free or glycoside form (Drosera peltata, Juglans cinerea, Juglans regia, Plumbago europaea). Hypericin content in Hypericum perforatum MT was 0.004%. The results obtained were in correlation with the literature data.
On the basis of literature data for oral safe dosage in humans for photoreactive substances and a posology of 150 drops daily, all MT studied are safe, except for MT containing more than 0.03% total furanocoumarins and furanocoumarin derivatives.