Mutagenic assessment and toxicological impact of bergenin in a phenolic-enriched extract from Endopleura uchi (Huber) Cuatrec bark, a medicinal plant from the Amazon rainforest.

Abstract

Endopleura uchi bark traditionally used in folk medicine attributed to its anti-inflammatory properties is due to the presence of bergenin. This study aimed to determine the toxicological parameters associated with exposure to a phenolic-enriched extract of E. uchi bark and bergenin a bioactive byproduct of this compound. The total phenolic and flavonoid contents were determined through spectrometric analyses, while phenolic compounds were identified using ultra-performance liquid chromatography coupled with high-resolution mass spectrometry (UPLC-MS). Antioxidant activity was assessed in vitro using the DPPH assay. Cytotoxicity and genotoxicity were assessed via the MTT assay and comet assay, respectively, whereas mutagenic activity was examined using Salmonella/microsome assay and micronucleus (MN) test. A high content of phenolic (732.22 ± 9.48 mg/g) GAE (gallic acid equivalence) and flavonoid 252.47 ± 5.7 mg/g QE (quercetin) compounds was found in bergenin the phenolic-enriched extract byproduct as well as isomers of gallic acid, epicatechin, isoquercitrin, castalagin, punicalin, and punicalagin. The DPPH value was 23.74 ± 0.45 μg/ml. In MTT assay, the extract exhibited an IC50 of 72.5 ± 2.6 µg/ml. Both extract and bergenin displayed genotoxic activity in L929 fibroblast cells at 50 µg/ml but not mutagenic effects in the Salmonella/microsome assay or MN test. Despite the genotoxic actions, E. uchi bark and bergenin extract did not induce gene or chromosomal mutations, suggesting a low risk of compromising genomic stability. The presence of bioactive compounds such as bergenin and punicalagin in E. uchi bark demonstrates a therapeutic potential of this native tree for treating inflammatory diseases.