Phytochemical Profile and Analgesic Properties of Chicory Root Extract in the Hot-Plate Test in Mice

Cichorium intybus L. (common chicory) is a medicinal plant valued for health-promoting effects. Although analgesic properties are known for chicory sesquiterpenes, the effects of extracts need yet to be explored. This study aimed to evaluate for the first time the analgesic effect (against nociceptive pain) of the root extract from C. intybus var. foliosum. The target evaluation was preceded by toxicity tests in vivo and phytochemical standardization of root extracts prepared with different extraction methods-pectinase-assisted, pressure-assisted, and a combination of both-to choose the most effective one. The phytochemical profiling involved UHPLC-PDA-ESI-MS/MS and UHPLC-PDA analyses. The toxicity and the analgesic effects were tested in mice following the OECD 423 guideline and the hot-plate test, respectively. The highest recovery of bioactive compounds was achieved for the pressure-assisted extract: 642.5 mg sesquiterpene lactones, 187.1 mg phenolic acids, and 47.3 g inulin/100 g of dry matter. The extract showed no toxic effects at the oral dose of 2000 mg/kg body weight, including no histopathologic changes, in mice within two weeks (GHS Category 5/Uncategorized). The maximum analgesic effect (MAE) of the extract at 600 mg/kg was 6.75% for rearing and 13.7% for jumping, with the impact on the nocifensive reactions not differing significantly from those of paracetamol at 60 mg/kg. Despite the relatively low effects at 600 mg/kg, the verified safety and abundance of active compounds encourage further studies on the extract and its active fractions as potential approaches to complementary pain therapy, with special concern for their mechanisms of action.