Anti-Inflammatory, Analgesic, and Anxiolytic Effects of Crude Extracts and Isolated Bioactive Fractional Compounds from Pouzolzia sanguinea

Pharmacological relevance: Ethnic people residing in the Chittagong Hill Tracts (CHTs) of Bangladesh use Pouzolzia sanguinea to alleviate flatulence, for menstruation, inflammation, insomnia, and analgesia. However, there is no scientific evidence regarding the bioactivity of these plants. Aim: This study aimed to isolate bioactive fractional compounds from Pouzolzia sanguinea (IFCPS) crude extract to assess the anti-inflammatory, analgesic, and anxiolytic activities. Materials and Methods: Preparative TLC-bioautography and silica gel two-stage column chromatography were used to isolate bioactive fractional compounds from P. sanguinea methanol crude extracts. The anti-inflammatory, analgesic, and anxiolytic activities of extracts and IFCPS were studied by inhibiting protein denaturation, acetic acid-induced writhing, Eddy’s hot plate, field cross, and hole cross methods. Results: The dried crude extract’s chemical analysis revealed alkaloids, flavonoids, terpenoids, saponins, vitamin C, and tannins. Nine single isolated fractional compounds (IFC1PS to IFC9PS) were isolated through TLC. Among these, IFC2PS exhibited (p ˂ 0.01) the most potent anti-inflammatory activity in the inhibition of protein denaturation studies (70.51%), which was slightly lower than acetyl salicylic acid (82.29%), at160 µg/mL. This inhibitory effect occurred in a dose-dependent manner. IFC2PS exhibited the most potent peripheral analgesic and moderate central analgesic effects compared to the standard. In contrast, IFC1PS showed moderate effects in both areas. IFC8PS showed superior anxiolytic activities compared to crude extracts and other IFCPS. Conclusions: Out of the nine fractional compounds isolated, the IFC2PS reduced pain and inflammation, whilst IFC8PS exhibited anxiolytic activities. This is the first comprehensive study demonstrating the anti-inflammatory, analgesic, and anxiolytic effects of crude extracts and isolated fractional compounds from the whole plant of P. sanguinea, which may have immediate experimental and clinical applications.