F. O. AMEGOR

Cymbopogon citratus (lemon grass) is a medicinal grass widely valued in ethnomedicine for its antimicrobial, antioxidant, and anti-inflammatory activities, with its bioactivity linked to essential oils, phenolics, and flavonoids. Although extensively used, there is limited comparative evidence on how solvent polarity influences the anti-inflammatory potential of its extracts. This study therefore evaluated the in vitro anti-inflammatory activities of ethanol (polar) and diethyl ether (non-polar) extracts of C. citratus in order to assess differences in solvent efficiency and bioactivity. Fresh leaves collected from the University of Benin were authenticated and extracted using standardized procedures, information was sourced from laboratory analyses combined with current literatures from PubMed, ResearchGate, ScienceDirect and Google Scholar. Extracts were tested in vitro for inhibition of protein denaturation, heat-induced haemolysis, antiproteinase activity, and lipoxygenase inhibition, with aspirin serving as the standard drug. Extraction yield was slightly higher for diethyl ether (1.72%) than for ethanol (1.56%). Both extracts exhibited concentration-dependent anti-inflammatory activity across all assays. In the protein-denaturation assay, ethanol extract inhibited 65.9% at 500 µg/ml while diethyl ether showed 69.4%, compared with 82.3% for aspirin. In the haemolysis test, ethanol recorded 61.7% and diethyl ether 58.4% inhibition, while aspirin reached 75.6%. Antiproteinase activity was 59.2% for ethanol and 56.8% for diethyl ether, against 70.4% for aspirin. Lipoxygenase inhibition was stronger in the diethyl ether extract (64.5%) than ethanol (60.1%), though both were lower than aspirin (78.2%). The findings confirm that C. citratus possesses measurable in vitro anti-inflammatory activity, supporting its traditional use in managing inflammation-related disorders. Solvent polarity was shown to influence the degree and spectrum of bioactivity, highlighting the importance of solvent selection in herbal preparation. However, the study was limited to in vitro models, two extraction solvents, and a single collection site. Future research should explore in vivo and clinical trials, and adopt advanced extraction techniques.

Cymbopogon citratus (lemongrass) is an aromatic and medicinal grass widely used in food, cosmetics, and traditional medicine for its antimicrobial, antioxidant, and anti-inflammatory properties. These activities are linked to its diverse phytochemicals, including essential oils, phenolic acids, and flavonoids. Although the plant has been extensively studied, limited comparative data exists on how solvent polarity influences the extraction of its nutritional and bioactive constituents. This study therefore evaluated the proximate composition, phytochemical distribution, and phenolic profile of C. citratus using ethanol (polar) and diethyl ether (non-polar) as extraction solvents. Laboratory analyses employed various methods, including gravimetric techniques for proximate and phytochemical composition, spectrophotometric and acid titration methods for phytochemical determination, and GC-FID for detailed phenolic profiling. Fresh samples collected from the University of Benin were authenticated and subjected to standardized proximate and phytochemical analyses, supported by current literatures from PubMed, ScienceDirect, MDPI, and Google Scholar. Extraction yield was slightly higher with diethyl ether (1.72%) than with ethanol (1.56%), reflecting the solvent’s efficiency in dissolving non-polar constituents. Proximate analysis revealed high carbohydrate content (71.820%) and crude fibre content (3.225%), moderate crude protein (6.133%), ash content (2.117%), and moisture content (16.720%), and very low-fat content (1.552%). Antinutritional factors such as oxalates, phytates, and cyanogenic glycosides were found only in trace amounts, confirming nutritional safety. Phytochemical screening detected alkaloids, flavonoids, tannins, saponins, steroids, terpenoids, cardiac glycosides, and phenolics in both extracts. Phenolic profiling showed diethyl ether enriched non-polar compounds including catechol (21.776ppm), hydroxyquinol (54.471ppm), and resorcinol (13.932ppm), while ethanol favored polar phenolics such as quinol (25.975ppm) and cinnamic acid (21.163ppm).