PROMISING ROLE OF LUTEOLIN FROM THE SPROUTS OF COCOS NUCIFERA L. IN INDOMETHACIN-INDUCED GASTRIC ULCER OF HUMAN GASTRIC ADENOCARCINOMA CELL LINE

Abstract

Plant-derived secondary metabolites and its derivatives represents the richness of potent novel bioactive compounds. Luteolin, a promising flavone belonging to flavonoids is present in fruits, vegetables and several medicinal plant and tree species with multiple pharmaceutical properties such as antioxidant, antiviral, diuretic, anti-inflammatory, antimicrobial, anticancer, anti-ulcer, antispasmodic, anti-allergic, anti-secretory, anti-angiogenic, anti-proliferative and several other properties. Cocos nucifera L. (Family: Arecaceae) is a well-known tree species commonly known as ‘Kalpavriksha’. The aim and objective of the study is to isolate a promising anti-ulcer bioactive compound, its characterization, bioassays and to test its anti-ulcer activity using an in vitro cell line model. Separation, isolation and purification of a promising bioactive compound from the coconut sprouts was performed through silica gel column and thin layer chromatography. The isolated fraction was then subjected to characterization by Ultra Violet-Visible (UV-Vis), Fourier Transform Infrared spectrophotometer (FTIR) analysis and structure elucidation through Nuclear Magnetic Resonance (NMR) and Mass Spectrometry (MS) studies. Based on the spectral details, the isolated bioactive compound from the sprouts of Cocos nucifera L. was identified as luteolin, a flavone compound. In vitro bioassays namely antioxidant assays (hydrogen peroxide assay, superoxide anion assay) and antiinflammatory assays (cyclooxygenase-COX-1, COX-2 and 5-lipoxygenase- LOX inhibitory activity) proved the bioactive potential of luteolin with minimum IC50 values. Anti-ulcer activity of luteolin was confirmed through its cytotoxic effect against human gastric adenocarcinoma epithelial (AGS) cell line with indomethacin-induced gastric ulcer which indicated a maximum per cent inhibition of infected AGS cells (90.39±0.26) with an IC50 value of 30.09 µg mL-1 whereas cimetidine (standard anti-ulcer drug) had 94.85±0.29 per cent inhibition with an IC50 value of 18.83 µg mL-1. In the, present work, identification of luteolin, a flavone has been reported for the first time from the sprouts (haustorium) of Cocos nucifera L. which is considered to be a promising anti-ulcer agent.