Assessment of genoprotective effects of Gentiana lutea extracts prepared from plants grown in field and in vitro

Abstract

Medicinal plant Gentiana lutea is considered as an official drug for gastrointestinal disorders in many pharmacopoeias. Its uncontrolled overexploitation led to the protection regime and encouraged development of in vitro culture. The aim of this work was to chemically characterize root and leaf methanol extracts of plant grown in plantation and in vitro conditions, and to determine their antigenotoxicity against heterocyclic aromatic amines IQ and PhIP, the food-borne mutagens that are formed during high temperature cooking of protein-reach foods. High yields and growth ratios were determined for in vitro plants. Higher content of polyphenols and flavonoids were determined in aerial parts, while UPLC-MS/MS analysis pointed at the richness of in vitro grown shoot extract (GLvS) in active constituents, and high amounts of gentiopicroside in all tested extracts. Notable amounts of sweroside were detected in plantation root extract (GLR) and in GLvS, and of loganic acid in plantation leaf extract (GLL) and GLvS. Two experimental models for genotoxicity/antigenotoxicity study, i.e. SOS/umuC test with metabolic activation (addition of rat liver S9 fraction) and alkaline comet assay on hepatocellur carcinoma HepG2 cells indicated dual effects: genotoxic of high and antigenotoxic of lower non-genotoxic doses. While in vitro extracts were genotoxic in both models, plantation extracts were active only in SOS/umuC with S9. In contrast, inhibition of genotoxicity was observed in both models for all extracts (up to 83 %). Results of DPPH assay indicated that antioxidativity could be responsible for antigenotoxic properties. In conclusion, genoprotective effect encourages further investigation of antigenotoxicity, while high growth ratio and richness of GLvS in active compounds justify the use of in vitro cultivation method.