Chemical composition and biological activity of lemongrass volatile oil and n-Hexane extract: GC/MS analysis, in vitro and molecular modelling studies
Shaza H. Aly, Abdullahi İbrahim Uba, Nilofar Nilofar, Taghreed A. Majrashi, Mahmoud A. El Hassab, Wagdy M. Eldehna, Gökhan Zengin, Omayma A. Eldahshan
Abstract
Lemon grass, formally identified as Cymbopogon citratus, is a plant that belongs to the Poaceae family. The present work aimed to examine the chemical composition by GC/MS analysis and assess the biological potential of C. citratus volatile oil and n-hexane extract. The volatile oil and n-hexane extract were evaluated for antioxidant potential and tested for their enzyme inhibition against tyrosinase, butyrylcholinesterase (BChE), acetylcholinesterase (AChE), α-amylase, and α-glucosidase. The chemical analysis of the lemongrass n-hexane extract (HE) and volatile oil (VO) revealed that the main constituents in the HE are aliphatic hydrocarbons (42.98%), triterpenoids (20.14%), and aromatic hydrocarbons (17.25%). Conversely, the main constituents of the (VO) are predominantly monoterpenes, namely α-citral (36.08%), β-citral (34.22%), and β-myrcene (13.84%). The oil showed more potent antioxidant potential in DPPH, ABTS, CUPRAC, FRAP, and phosphomolybdenum (10.18, 35.69 mg Trolox equivalent/g, 98.97 and 69.73 mg Trolox equivalent/g and 43.01 mmol Trolox equivalent/g). The HE displayed higher BChE (1.53 mg Galanthamine equivalent)/g), as well as α-amylase and α-glucosidase inhibitory activities (0.39 and 2.40 mmol Acarbose equivalent/g). The VO demonstrated more potent tyrosinase inhibitory activities (57.19 mg Kojic acid equivalent/g) along with acetyl and butyrylcholinesterase inhibition. Dominant compounds exhibited the ability to bind with high affinity to various target proteins, with a particular affinity for AChE and BChE. The volatile oil and n-hexane extract of C. citratus show significant promise as a viable choice for the advancement of novel therapeutic strategies aimed at addressing oxidative stress, neurodegeneration, and diabetes.