ABSTRACT
One new hydronaphthalenone derivative (1) was isolated from the broth extract of the endophytic fungus Daldinia eschscholtzii PSU-STD57 together with five known compounds, isosclerone (2), 8-methoxy-1-naphthol, 1,8-dimethoxynaphthalene, 2,6-dihydroxyphenyl-1-butan-1-one and tyrosol. The structures were assigned by spectroscopic methods. All the compounds were tested for antimicrobial activity against Staphylococcus aureus, methicillin-resistant S. aureus and Microsporum gypseum.
Subject(s)
Anti-Bacterial Agents/chemistry , Antifungal Agents/chemistry , Naphthalenes/chemistry , Rhizophoraceae/microbiology , Xylariales/chemistry , Anti-Bacterial Agents/isolation & purification , Antifungal Agents/isolation & purification , Endophytes/chemistry , Fermentation , Methicillin-Resistant Staphylococcus aureus/drug effects , Microbial Sensitivity Tests , Microsporum/drug effects , Molecular Structure , Naphthalenes/isolation & purification , Plant Leaves/microbiology , Staphylococcus aureus/drug effectsABSTRACT
Thai medicinal plants represent a rich source of potential anti-parasitic compounds. 1-hydroxy-2-hydroxymethylanthraquinone (CFQ) purified from Coptosapelta flavescens, a plant commonly used to expel intestinal worms, indicated potential anti-giardial agent as shown in a previous study. This study aims to investigate its mechanism of action. We assessed whether CFQ was involved as an inducer of apoptosis as well as having effects on the fine structure of Giardia intestinalis trophozoites. We observed the consequences of exposing G. intestinalis trophozoites to CFQ and metronidazole, both had an IC50 of 0.42µg/ml, after 6, 12 and 24h exposure. An apoptosis in trophozoite was confirmed by the AnnexinV-FITC assay and as viewed by flow cytometry. CFQ at its IC50 induced apoptosis as early as 6h after incubation while metronidazole produced little or no apoptosis at its IC50 value. Ultrastructural analyzes at 24h demonstrated that both CFQ and metronidazole induced several physical alterations, including the appearance of wrinkled and rounded cells, membrane blebbing, ventral disc damage, electron dense precipitates in the nuclei, all of which were indicative of cell death. However, membrane rupture was found only in G. intestinalis exposed to CFQ and this proved the induction of apoptosis. Taken together, we have provided a mechanistic explanation of the action of CFQ against G. intestinalis trophozoites. These results have provided further evidence that CFQ is a new compound that has the potential for use to treat infections from G. intestinalis.
Subject(s)
Anthraquinones/pharmacology , Antiprotozoal Agents/pharmacology , Giardia lamblia/drug effects , Giardiasis/drug therapy , Plant Extracts/pharmacology , Animals , Antiprotozoal Agents/isolation & purification , Inhibitory Concentration 50 , Rubiaceae/chemistry , Thailand , Trophozoites/drug effectsABSTRACT
Investigation of the acetone and methanol extracts of the roots of Coptosapelta flavescens using various chromatographic techniques led to the isolation of four anthraquinones (1 and 3-5) and one naphthoquinone (2). 1,4-Dimethoxy-2-methylanthraquinone (1) and 2-amino-3-methoxycarbonyl-1,4-naphthoquinone (2) are reported as natural compounds for the first time. This is the first report on the phytochemistry and biological activity of compounds from C. flavescens.