Aristolochia Plant Used in Congolese Traditional Medicine: Ethnopharmacology and Chromatographic Analysis for Aristolochic Acids Identification and Quantification

The Aristolochia genus contains aristolochic acids (AAs), nephrotoxic and carcinogenic compounds found in many species. Although the use of Aristolochia has been restricted worldwide due to safety concerns, no information is currently available on the species occurring in the flora of the Democratic Republic of the Congo (DRC). This lack of information regarding occurrence, use, and chemical composition of Aristolochia species limits the evaluation of potential exposure risks associated with traditional medicinal practices. This study identified Aristolochia species reported in the DRC through a bibliographic survey and assessed the presence of AAs in A. heppii, a species native to Katanga. Microscopic examination of root powders and HPLC-DAD/MS analysis of hydroalcoholic and aqueous extracts were performed according to the European Pharmacopoeia on one authenticated sample and twelve commercial samples purchased in Lubumbashi. Microscopy confirmed diagnostic features consistent with Aristolochia. Mass spectrometry analysis identified AAs, with AA-I quantified in hydroalcoholic extracts at 566 ± 5 ppm to 3533 ± 32 ppm (0.057–0.353% w/w) and in the aqueous extract at 204.2 ± 0.4 ppm (0.020% w/w). These results demonstrate that traditional preparations of A. heppii may lead to exposure to AA-I and underline the need for risk assessment and regulatory oversight.