There are several lines of indications on the importance of plants as accepted sources of therapeutic agents since most synthetic antioxidants and antibiotics have been associated with cytotoxicity and/or microbial re...There are several lines of indications on the importance of plants as accepted sources of therapeutic agents since most synthetic antioxidants and antibiotics have been associated with cytotoxicity and/or microbial resistance. In this study, the antioxidant and antimicrobial activities of a brown compound recovered from the ethanol extractable fraction (EEF) and white crystals isolated from the chloroform-methanol elution (CME) following column chromatography of the ethanolic extracts of roots of Securinega virosa were examined. Preparations from the white crystalline compound recorded greater antioxidant activity and antimicrobial activities than the crude ethanol extracts of S. virosa. Both the ethanol extract and the crystals showed significant antimicrobial activities against all microbes employed in this study. The crystalline compound demonstrated the highest zone of inhibition against the microbes Enterococcus faecalis with varied inhibitory activities with respect to other microorganisms. The least inhibition was against Pseudomonas fluorescens. The overall range was 8.0 - 22.5 mm. The EEF of the roots of S. virosa recorded its highest activity against Staphylococcus aureus and Escherichia coli. There was varied inhibitory activity against other organisms;the least was against Micrococcus liteus. The zone of inhibition ranged 6.33 - 17.67 mm. Similar to the trends in susceptibility test, the EEF showed appreciable minimum inhibitory concentration (MIC), ranging from 3.13 - 25 mg/mL against test microorganisms while the crystalline preparation had a MIC range of 1.5 - 25 mg/mL except against Salmonella typhii which was 50 mg/mL. Both extracts demonstrated their highest activity against E. faecalis reducing significantly in a dose-dependent manner by each sample against the rest of the test microbes. However, the standard broad-spectrum antibiotic, chloramphenicol, used elicited a zone of inhibition ranging from 0 - 30 mm but with no activity against Streptococcus thermophilus. We conclude that both the EEF and the white crystal compound isolated from the CME chromatographic fraction are potentially excellent sources of antioxidant and antimicrobial compounds.展开更多
[Objectives]The purpose was to determine the contents of quercetin and kaempferol in Flueggea virosa(Roxb.ex Wild.)Baill.,thereby providing reference data for the research and application of F.virosa.[Methods]Querceti...[Objectives]The purpose was to determine the contents of quercetin and kaempferol in Flueggea virosa(Roxb.ex Wild.)Baill.,thereby providing reference data for the research and application of F.virosa.[Methods]Quercetin and kaempferol in F.virosa were extracted with ultrasonic method,using dilute hydrochloric acid-methanol(1∶10)solution as the extraction solvent,and their contents were determined with RP-HPLC.[Results]The contents of quercetin and kaempferol in F.virosa were 0.2336 and 0.3272 mg/g,respectively.[Conclusions]The method has high speed,high resolution,high sensitivity,accurate and reliable detection results,and can be used as a method for the determination of quercetin and kaempferol in F.virosa.展开更多
Two new compounds,11,11 ’-dimer of scopoletin（1） and 11-O-β-glucopyranosylhamaudol（2）,together with seven known compounds were isolated and identified from the whole grass of Cicuta virosa.The chemical structure...Two new compounds,11,11 ’-dimer of scopoletin（1） and 11-O-β-glucopyranosylhamaudol（2）,together with seven known compounds were isolated and identified from the whole grass of Cicuta virosa.The chemical structures of the isolated compounds were elucidated using different spectroscopic methods.In addition,the chemical constituents were evaluated for multidrug resistance reversing activity towards doxorubicin-resistant K562/A02 cells.Compounds 1,8,and 9 were endowed with remarkable MDR reversing effects.展开更多
Three new indole alkaloids, flueindolines A–C(1–3), along with nine known alkaloids(4–12), were isolated from the fruits of Flueggea virosa(Roxb. ex Willd.) Voigt. Compounds 1 and 2 are two new fused tricyclic indo...Three new indole alkaloids, flueindolines A–C(1–3), along with nine known alkaloids(4–12), were isolated from the fruits of Flueggea virosa(Roxb. ex Willd.) Voigt. Compounds 1 and 2 are two new fused tricyclic indole alkaloids possessing an unusual pyrido[1, 2-a]indole framework, and 3 presents a rare spiro(pyrrolizidinyl-oxindole) backbone. Their structures with absolute configurations were elucidated by means of comprehensive spectroscopic analysis, chemical calculation, as well as X-ray crystallography. Chiral resolution and absolute configuration determination of the known compounds 4, 10, and 11 were reported for the first time. The hypothetical biogenetical pathways of 1–3 were herein also proposed.展开更多
文摘There are several lines of indications on the importance of plants as accepted sources of therapeutic agents since most synthetic antioxidants and antibiotics have been associated with cytotoxicity and/or microbial resistance. In this study, the antioxidant and antimicrobial activities of a brown compound recovered from the ethanol extractable fraction (EEF) and white crystals isolated from the chloroform-methanol elution (CME) following column chromatography of the ethanolic extracts of roots of Securinega virosa were examined. Preparations from the white crystalline compound recorded greater antioxidant activity and antimicrobial activities than the crude ethanol extracts of S. virosa. Both the ethanol extract and the crystals showed significant antimicrobial activities against all microbes employed in this study. The crystalline compound demonstrated the highest zone of inhibition against the microbes Enterococcus faecalis with varied inhibitory activities with respect to other microorganisms. The least inhibition was against Pseudomonas fluorescens. The overall range was 8.0 - 22.5 mm. The EEF of the roots of S. virosa recorded its highest activity against Staphylococcus aureus and Escherichia coli. There was varied inhibitory activity against other organisms;the least was against Micrococcus liteus. The zone of inhibition ranged 6.33 - 17.67 mm. Similar to the trends in susceptibility test, the EEF showed appreciable minimum inhibitory concentration (MIC), ranging from 3.13 - 25 mg/mL against test microorganisms while the crystalline preparation had a MIC range of 1.5 - 25 mg/mL except against Salmonella typhii which was 50 mg/mL. Both extracts demonstrated their highest activity against E. faecalis reducing significantly in a dose-dependent manner by each sample against the rest of the test microbes. However, the standard broad-spectrum antibiotic, chloramphenicol, used elicited a zone of inhibition ranging from 0 - 30 mm but with no activity against Streptococcus thermophilus. We conclude that both the EEF and the white crystal compound isolated from the CME chromatographic fraction are potentially excellent sources of antioxidant and antimicrobial compounds.
基金Natural Science Research Project of Guangxi University of Chinese Medicine(P2012025)Guangxi University Laboratory of Extraction,Purification and Quality Analysis of Traditional Chinese Medicine(J1606701).
文摘[Objectives]The purpose was to determine the contents of quercetin and kaempferol in Flueggea virosa(Roxb.ex Wild.)Baill.,thereby providing reference data for the research and application of F.virosa.[Methods]Quercetin and kaempferol in F.virosa were extracted with ultrasonic method,using dilute hydrochloric acid-methanol(1∶10)solution as the extraction solvent,and their contents were determined with RP-HPLC.[Results]The contents of quercetin and kaempferol in F.virosa were 0.2336 and 0.3272 mg/g,respectively.[Conclusions]The method has high speed,high resolution,high sensitivity,accurate and reliable detection results,and can be used as a method for the determination of quercetin and kaempferol in F.virosa.
基金Financial supported from the National Natural Science Foundation of China (Nos. 81202422, 21472113, and 31500280)the Natural Science Foundation of Shandong Province (No. ZR2012HQ024)
文摘Two new compounds,11,11 ’-dimer of scopoletin（1） and 11-O-β-glucopyranosylhamaudol（2）,together with seven known compounds were isolated and identified from the whole grass of Cicuta virosa.The chemical structures of the isolated compounds were elucidated using different spectroscopic methods.In addition,the chemical constituents were evaluated for multidrug resistance reversing activity towards doxorubicin-resistant K562/A02 cells.Compounds 1,8,and 9 were endowed with remarkable MDR reversing effects.
基金the National Key R & D Program of China (No. 2018YFC1706200)the National Natural Science Foundation of China (Nos. 81630095, 81622045, and 81803379)+2 种基金the Science & Technology Program of China (No.2019ZX09735002-003)the China Postdoctoral Science Foundation(Nos. 2019T120794, and 2018M633291)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program (No. 2017BT01Y036)。
文摘Three new indole alkaloids, flueindolines A–C(1–3), along with nine known alkaloids(4–12), were isolated from the fruits of Flueggea virosa(Roxb. ex Willd.) Voigt. Compounds 1 and 2 are two new fused tricyclic indole alkaloids possessing an unusual pyrido[1, 2-a]indole framework, and 3 presents a rare spiro(pyrrolizidinyl-oxindole) backbone. Their structures with absolute configurations were elucidated by means of comprehensive spectroscopic analysis, chemical calculation, as well as X-ray crystallography. Chiral resolution and absolute configuration determination of the known compounds 4, 10, and 11 were reported for the first time. The hypothetical biogenetical pathways of 1–3 were herein also proposed.
