Background: The purpose of these studies was to determine the safety of a botanical treatment for supporting healthy liver function developed in Peru. The formulation, A4+, contains extracts of Curcuma longa L. rhizome (A4R), Cordia lutea Lam. flower (A4F) and Annona muricata L. leaf (A4L). The tests were used to support an application for a non-traditional Natural Health Product Licence from the Natural Health Product Directorate of Health Canada and future clinical trials.
Methods: Besides reviewing the scientific and clinical information from Peru on the ingredients and conducting an initial Ames test for mutagenicity, we analysed A4+ for its chemical profile and tested genotoxicity (micronucleus test) and general toxicity (28-day repeated dose).
Results: A4+ and extracts from the three plants provided distinctive chemical fingerprints. A4L contained acetogenins, requiring a second chromatographic method to produce a specific fingerprint. The Ames test proved positive at the highest concentration (5,000 μg/mL) but A4+ showed no evidence of genotoxicity in the more specific mouse micronucleus test. The 28-day repeated dose (general toxicity) study in rats showed no toxicity at 2,000 mg/kg.
Conclusions: We conclude that under the conditions of these studies, A4+ shows no evidence of toxicity at the levels indicated. A no observed adverse effect level (NOAEL) of 2,000 mg/kg was assigned.