A new phloroglucinol from Dryopteris fragrans and its antibacterial activity in vitro / 中国中药杂志

A new phloroglucinol was isolated from 50% ethanol extract of Dryopteris fragrans by silica gel column chromatography, Sephadex LH-20 gel column chromatography, thin-layer chromatography(TLC), and preparative liquid column chromatography. On the basis of MS, ~1H-NMR, ~(13)C-NMR, and reference materials, compound 1 was identified as 2,5-cyclohexadien-1-one, 2-{[2,6-dihydroxy-4-methoxy-3-methyl-5-(1-isobutyl)phenyl]methyl}-3,5-dihydroxy-4,4-dimethyl-6-(1-oxobutyl)(1), and named disaspidin BB. Compound 1 was evaluated for its antibacterial activity. The experimental results showed that compared with the commonly used topical antibiotics erythromycin or mupirocin, disaspidin BB exhibited significant antibacterial activities against Staphylococcus epidermidis(SEP), S. haemolyticus(SHA), and methicillin-resistant S. aureus(MRSA)(P<0.05). Additionally, disaspidin BB was sensitive to ceftazidime-resistant SEP1-SEP4, SHA5-SHA7, MRSA8, and MRSA9. The MIC values of disaspidin BB against SEP and SHA were 1.67-2.71 μg·mL~(-1) and 10.00-33.33 μg·mL~(-1) respectively. Disaspidin BB has good antibacterial activities and deserves development as a new anti-infective drug for external use.

Research progress on chemical constituents of Hypericum attenuatum and their pharmacological activities / 中草药

Hypericum attenuatum is a Guttiferae Hypericum Linn. plant, which is a folk commonly used drug.H. attenuatum has great medical development value of detoxicating, diminishing inflammation, stopping bleeding, promoting tissue regeneration, regulating menstruation, activating blood, and so on. It was used for empyrosis, hyperhidrosis, especially heart disease in Northeast area of China from the folk records. Modern research shows that it has flavonoids, volatile oils, and phloroglucinol derivative; And it has anti-arrhythmia, antimyocardial ischemia, antitumor, antidepression, antibacterial, and other pharmacologic actions. The recent progress in the studies of the constituents and their pharmacological activity of this plant is reviewed in this paper in order to provide reference for clinical application, quality control and drug discovery.

Isolation and antibacterial activities of phloroglucinol derivatives from Dryopteris crassirhizoma / 中草药

Objective To isolate the phloroglucinol derivatives in Dryopteris crassirhizoma and to discuss its antibacterial activity. Methods The phloroglucinol derivatives were isolated and purified by column chromatography on silica gel, Sephadex LH-20, semi preparative liquid phase, and recrystallization. Structures were proved by physicochemical properties and spectral methods (MS, 1H-NMR, 13C-NMR). The antibacterial activities against fungi and bacteria were tested by CLSI M38-A2 and M07-A9. Results 10 derivatives were obtained from ethanol extracts of D. crassirhizoma, and were identified as 1-butyrylphloroglucinol (1), 1-methyl-3-butyrylphloroglucinol (2), 2-acetyl-4-butyrylphloroglucinol (3), 1-methyl-3-acetyl-5-butyrylphloroglucinol (4), flavaspidic acid PB (5), norflavaspidic acid AB (6), flavaspidic acid AA (7), filixic acid ABA (8), flavaspidic acid AB (9), and filixic acid ABP (10). The antibacterial activity of compound 8 against Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S. epidermidis) was similar to cefoxitin (positive control), and the MIC of compound 8 was 2.5 μg/mL. Conclusion Compounds 1-4, new compounds, are isolated from D. crassirhizoma. Compound 8 has both antibacterial activities against fungi and bacteria.

Isolation and Preparation of Phloroglucinol Derivatives from Dryopteris Fragrans by Semi-preparation HPLC / 中国药师

Objective:To isolate and prepare the reference substances of phloroglucinol derivatives from Dryopteris fragrans by semi-preparation HPLC. Methods:After reflux extraction of Dryopteris fragrans with petroleum ether,the extracting solution was con-centrated and separated by silica gel column chromatography,and then isolated by semi-preparation HPLC. The isocratic elution was carried out using acetonitrile as the mobile phase at 3. 0 ml·min-1 and the injection volume was 0. 5 ml. Two phloroglucinol deriva-tives were isolated. Results:The chemical structure of the two phloroglucinol derivatives respectively was aspidin BB with the purity of 98. 81% and aspidin PB with the purity of 98. 57% by ultra high performance liquid chromatography. Conclusion:The isolation of as-pidin BB and aspidin PB by semi-preparation HPLC is simple and fast with the purity over 98%,which can be used to prepare the ref-erence substances.

Research advances on phloroglucinol derivatives in plants of Eucalyptus L'Héritier / 中草药

The plants from Eucalyptus L'Héritier, a main genus of Myrtaceae family, are commonly called as eucalyptus tree, the woods, leaves, flowers, and fruits of which are a kind of important raw materials for chemical industry, medicine, and spices. For a long time, the species in Eucalyptus L'Héritier are commonly used as folk medicine to treat influenza, dysentery, eczema, and injuries. The mainly bioactive chemical constituents in the species of Eucalyptus L'Héritier are phloroglucinol derivatives, which are unique to the species in Eucalyptus L'Héritier. Many phloroglucinol derivatives exhibit the interesting pharmacological activities, such as antimicrobial, antiviral, antitumor effects, and so on. The phloroglucinol derivatives include simple, dimeric, and complex phloroglucinol derivatives originating from mixed biogenesis involving the terpene pathways. By now, 96 phloroglucinol derivatives have been isolated from the plants of Eucalyptus L'Héritier. Advance in study on their chemical constituents with the biological activities are summarized.

The Antidepressant-like Effect of Hyperbrasilol B, A Natural Dimeric Phloroglucinol Derivative is Prevented by Veratrine, a Sensitive-Voltage Na+ Channel Opener.

Aims: South Brazilian Hypericum species are a source of dimeric structures, constituted of filicinic acid and phloroglucinol moieties, which present antidepressant-like effects mediated by monoaminergic neurotransmission in rodents. Here, we show that hyperbrasilol B, a phloroglucinol derivative from Hypericum caprifoliatum, presents antidepressant-like activity in mice forced swimming test (FST). The aim of this study was to determinate if Na+ channels are important to the antidepressant-like effect of hyperbrasilol B and also verify the effect of this compound on Na+, K+ ATPase activity in the cerebral cortex and hippocampus of mice. Methodology: We assessed the effects of veratrine, a Na+ channel opener on antidepressant-like effect of hyperbrasilol B by using mice FST. Veratrine (0.06 mg/kg) and hyperbrasilol B (10 mg/kg) were given i.p. 60 and p.o. 30 min, respectively, before the test. In another batch of experiments different groups of mice were treated with hyperbrasilol B 10 mg/kg, p.o. (Single administration or once a day during 3 days). Two hours after the acute or after the last of the three treatments, the brain structures were removed for measuring Na+, K+ ATPase activity. Results: Veratrine was able to prevent the anti-immobility effect of hyperbrasilol B on the FST, suggesting that its antidepressant-like effect might be due to Na+ influx modifying properties. Animals treated for 3 consecutive days with hyperbrasilol B presented a significant increase in the hippocampus Na+, K+ ATPase activity. The acute treatment was ineffective. Conclusion: Alterations in the Na+ gradient may be implicated in the antidepressant-like effect of hyperbrasilol B.