RESUMO
AIMS: The aim of this study was to investigate the antimicrobial activities of Etlingera pubescens, and to isolate and identify the antimicrobial compound. METHODS AND RESULTS: The crude extracts of E. pubescens were obtained through methanol extraction, and evaluated for antimicrobial activities. From this extract, 1,7-bis(3,4-dihydroxyphenyl)heptan-3-yl acetate (etlingerin) was isolated. When compared to curcumin (a compound with a similar chemical structure), etlingerin showed twofold lower minimum inhibitory concentration values while also being bactericidal. Through time kill assay, etlingerin showed rapid killing effects (as fast as 60 min) against the Gram-positive bacteria (Staphylococcus aureus ATCC 43300 and Bacillus subtilis ATCC 8188). Further assessment revealed that etlingerin caused leakage of intracellular materials, therefore suggesting alteration in membrane permeability as its antimicrobial mechanism. Cytotoxicity study demonstrated that etlingerin exhibited approximately 5- to 12-fold higher IC50 values against several cell lines, as compared to curcumin. CONCLUSIONS: Etlingerin isolated from E. pubescens showed better antibacterial and cytotoxic activities when compared to curcumin. Etlingerin could be safe for human use, though further cytotoxicity study using animal models is needed. SIGNIFICANCE AND IMPACT OF THE STUDY: Etlingerin has a potential to be used in treating bacterial infections due to its good antimicrobial activity, while having potentially low cytotoxicity.
Assuntos
Antibacterianos/farmacologia , Antibacterianos/toxicidade , Diarileptanoides/farmacologia , Diarileptanoides/toxicidade , Bactérias Gram-Positivas/efeitos dos fármacos , Zingiber officinale/química , Animais , Antibacterianos/efeitos adversos , Antibacterianos/isolamento & purificação , Bornéu , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Células Cultivadas , Curcumina/farmacologia , Diarileptanoides/efeitos adversos , Diarileptanoides/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Permeabilidade/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologiaRESUMO
OBJECTIVE: Nonsteroidal anti-inflammatory drugs (NSAIDs) are a group of drugs widely used around the world for their analgesic, antipyretic and anti-inflammatory effect, but still have many limitations due to their side effects. So, these lead to the development of a new approach to search for a new product from natural plants that have similar therapeutic effects without common side effects like gastrointestinal ulcers. METHODS: The anti-inflammatory effect of ß-amyrin palmitate (1) as triterpene and 1,7-bis (4- hydroxyphenyl) hept-4-en-3-one (2) as diarylheptanoid, isolated from Pellacalyx axillaris was studied by molecular docking to find the probability of binding position and binding strength of new compounds with particular Prostaglandin G/H synthase 2 (PDB ID: 1CX2). In vivo acute anti-inflammatory activity of the isolated compounds (1 and 2) was evaluated in rats using the egg-white induced edema model of inflammation in a dose correspondent to 3 mg/Kg of Diclofenac Sodium. RESULTS: The tested isolated compounds showed a high activity to inhibit the swelling in paw edema and their anti-inflammatory effect began shortly after the injection of the egg white and continued to the end of the experiment in comparison to the reference and control. CONCLUSION: The isolated compounds show a rapid onset of action and a very potent effect, this may be related to their suitable acidity and may have perfect hydrophilic -lipophilic balance. This is the first study of anti-inflammatory effect using Paw edema model and molecular docking.