Gas chromatograph-mass spectrometric profiles, in vitro anti-inflammatory and antioxidant properties of n-butanol and aqueous fractions of ethanol leaf extract of Irvingia gabonensis

Abstract

Irvingia gabonensis (Bush mango) leaf is reportedly used locally in the treatment and management of a myriad of pathological conditions. This study therefore investigated the GC-MS profiles, in vitro anti-inflammatory and antioxidant properties of n-butanol and aqueous fractions of ethanol leaf extract of Irvingia gabonensis. In vitro anti-inflammatory and antioxidant properties of the fractions, GC-MS profiling and preliminary phytochemical screening, were done using standard methods. n-Butanol and aqueous fractions of ethanol leaf extract of Irvingia gabonensis showed potent inhibition of Nuclear factor-kappa B (NF-kB), Cyclooxygenase-2 (COX-2), Angiotensin-converting enzyme (ACE), Interleukin-6 (IL-6), Tumor necrosis factor-α (TNF-α), as well as H₂O₂ and DPPH, at various concentrations, when compared with the reference standard drugs. The two fractions also exhibited potent reducing powers at various concentrations. Furthermore, the total phenolic contents of the n-butanol and aqueous fractions were 17.00 ± 0.00 mg GAE/g and 14.00 ± 0.00 mg GAE/g, respectively. GC-MS analyses of the n-butanol fraction revealed the presence of some bioactive phyto-compounds, the major ones being: Cycloserine; Acetic acid; 1-Butanol; Bicyclo [4.2.0] octa – 1,3,5-triene; 2,4.-Di-tert-butyl phenol and Phenol, 3,5-bis (l,ldimethyethyl) and Phensuximide. Similarly, the major bioactive compounds found in the aqueous fraction were: Propane, 2.(ethenyloxy)-; Acetic acid; Bicyclo [4.2.0] octa – 1,3,5-triene; Cetene; Cis, cis, cis – 7,10,13-Hexadecatrienal; 2,4-Di-tert-butyl phenol; Phenol, 3,5, bis (1, 1- dimethylethyl); 1 – pentadecene; v-Triazole-4,5-dicarboxylic acid,1-Benzyl- and Phensuximide. Preliminary phytochemical screening of the n-butanol and aqueous fractions revealed the presence of important phytochemicals. It is concluded that, n-butanol and aqueous fractions of ethanol leaf extract of Irvingia gabonensis are promising anti-inflammatory and antioxidant agents that could be vital in the mitigation of inflammation and oxidative stress.