Anti-Inflammatory and Antimicrobial Activities of Essential Oil of Urochloa distachya (L.)

Background

Herbal medicines have been valued for centuries as potent treatments for various conditions, including inflammatory and microbial infections. Urochloa distachya (Signal grass), an annual grass belonging to the Poaceae family, is characterized by lance-shaped leaves and 2-3 racemes. This plant is native to tropical regions of Asia and Africa but has also spread to other regions. It thrives in hot, humid climates, particularly during monsoon seasons. Materials and methods: The anti-inflammatory activity was evaluated using the carrageenan-induced paw edema model in experimental animals. Paw edema was induced by injecting carrageenan into the hind paw, and the extent of inflammation was measured at specific time intervals. The antimicrobial activity was assessed using the disk diffusion method. The zone of inhibition around the discs was measured to determine antimicrobial efficacy.

Results

GC-MS analysis of the essential oil of Urochloa distachya identified eight phytoconstituents, Phytol (59.91%) is identified as the highest peak compound. The anti-inflammatory properties of the plant were evaluated using a carrageenan-induced paw edema model in rats. At a dose of 400 mg/kg, the essential oil significantly (p<0.05) reduced paw edema, achieving a notable inhibition rate of 56.5% at the 4^th hr. The antibacterial activity was evaluated against S. typhi and S. aureus. Molecular docking study was performed using protein COX-2, IL-1β, NF-κB, Phospholipase and TNF-α. β-Carotene showed the highest docking scores of -9.0, -7.8, -7.6, -7.3 and -7.7 against COX-2, IL-1β, NF-κB, Phospholipase and TNF-α, respectively. Similarly, docking scores of -7.7, -7.8 and -7.7 were observed against Dihydropteroate synthase, Transpeptidase and Type I dehydroquinase.

Conclusion

Urochloa distachya exhibits substantial potential as a natural source of essential oils with potent anti-inflammatory and antimicrobial properties, underscoring its potential for future therapeutic applications.