Anti-inflammatory study on crude methanol extract and different fractions of Eremostachys laciniata

Context: Eremostachys laciniata (L.) Bunge (Lamiaceae), which has been reported as a rich source of flavonoids, is one of the rarely explored species of the genus Eremostachys. Objective: In this study, the crude methanol extract and different fractions of E. laciniata were investigated for in vivo anti-inflammatory properties. Material and methods: Shade-dried leaves of E. laciniata were exhaustively extracted by percolation with methanol (80%) to obtain 2509 of crude methanol extract (El), followed by fractionation with different organic solvents to get the n-hexane (Elh), chloroform (Elc), ethyl acetate (Ele), butanol (Elb), and water (Elw) fractions. An in vivo anti-inflammatory study of the crude extract and sub-crude fractions was carried out in rats using the carrageenan model. Results:The Ele fraction was found to be the most potent inhibitor of edema formation by inducing a maximum inhibitory effect of 74.2% at the 300 mg/kg dose, during 3 h post carrageenan injection. The El extract and Elc fraction also showed good anti-inflammatory properties at the same dose. Discussion:The demonstration of excellent anti-inflammatory activity by the plant chiefly concentrating in the Ele fraction and the appearance of peak activity in the latter phase of the experiment suggested the presence of relatively low-polar substances with arachidonic acid metabolite inhibition property. Conclusion: The plant may be an excellent source in the future for activity-guided isolation of important anti-inflammatory substances.