Chemical composition and anti-inflammatory activity of essential oils from resin of Commiphora species

Abstract

ABSTRACT. Essential oils (EOs) were prepared by the hydro-distillation technique from the resins of four Commiphora species and analyzed by GC-MS. Major constituents of EOs were a-copaene (22.71%), β-caryophyllene (28.03%) and β-caryophyllene oxide (13.89%) for C. sphaerocarpa; a-pinene (29.1%) for C. africana; hexadecane (14.1%) for C. habessinica and δ-cadinene (31.5%) for C. schimperi. We investigated the anti-inflammatory effects of EOs in lipopolysaccharide (LPS) stimulated RAW 264.7 macrophages by measuring nitric oxide (NO). The effect in mRNA or protein level after EO treatment were evaluated by RT-PCR and Western blot analysis, respectively. Among four Commiphora species, C. sphaerocarpa EO demonstrated a significant inhibition of LPS by 27.2±3.6% at 10 μg/mL and 62.3±5.2% at 20 μg/mL. C. sphaerocarpa EO inhibited LPS mediated iNOS over expression in both protein and mRNA level with dose dependent manner. It inhibited phosphorylation of ERK1/2, p38, ATF2. The enhanced anti-inflammatory activity of the EO of the plant was due to HO-1 expression by ROS dependent Nrf2 activation in RAW264.7 cells. These findings indicate C. sphaerocarpa EO inhibits the pro-inflammatory responses by inhibiting MAPK/ATF2, and triggering ROS/Nrf2/HO-1 signaling. Therefore, C. sphaerocarpa EO could have potential for useful therapeutic candidate preventing and treating inflammatory diseases.

KEY WORDS: GC-MS, Anti-inflammatory, C. africana, C. habessinica, C. sphaerocarpa, C. schimperi

Bull. Chem. Soc. Ethiop. 2022, 36(2), 399-415.                                                              

DOI: https://dx.doi.org/10.4314/bcse.v36i2.13