In vitro Repression of Cyclooxygenase, Acetylcholinesterase Activities and Bacterial Growth by Trans-phytol and a Glycolipid from the Leaves of Homalomena sagittifolia

Abstract

Background and Objective: The leaf of Homalomena sagittifolia was reported to have anti-inflammatory, antimicrobials, narcotic, violent intoxication and hallucinogen effects. This study highlights isolation, identification and biological activities of two compounds from the leaves of H. sagittifolia. Methodology: Two isolates were investigated for their inhibitory effects against cyclooxygenase and acetylcholinesterase enzymes. They were also tested for antimicrobial effects against five pathogenic bacterial strains using the micro-dilution assay. The structure of the two isolates were elucidated by interpretation of spectroscopic data and previous available reports in literature. They were identified to be trans-phytol (1) and diacylglyceroglycolipid (2). The compounds were investigated for their anti-inflammatory, anticholinergic and antimicrobial effects using the cyclooxygenase, the microplate and the antimicrobial micro-dilution assays, respectively. Results: Compound 2 possessed good activity against both COX-1 (IC 50 = 38) and COX-2 (IC 50 = 48). The IC 50 values observed with the indomethacin were 4.1 and 181 μM against COX-1 and COX-2, respectively. The two compounds also inhibited activity of acetylcholinesterase with an IC 50 values of 8.6 μM (2), 24 μM (1) and 3.3 μM (galanthamine). Compound 2 showed remarkable activity against Gram-negative bacteria Pseudomonas stutzeri and Klebsiella pneumoniae with an MIC value of 98 μM. The MIC values recorded for tetracycline were 87 and 175 μM against P. stutzeri and K. pneumonia, respectively. Conclusion: These results indicated the potential pharmacological properties of the leaves of H. sagittifolia and supported the traditional uses of the plant. Further studies are needed to understand its molecular interactions. This may lead to the development of standardized crude drugs and/or nutraceutical agents.