Analysis of Chemical Constituents in Ethanol Extract of Cyclocarya paliurus Dried Leaves by UHPLC-Q-TOF/MS / 中国实验方剂学杂志

ObjectiveChemical components in ethanol extract of Cyclocarya paliurus dried leaves were analyzed by ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry （UHPLC-Q-TOF/MS）. MethodAn Agilent Poroshell 120 EC-C18 column （3.0 mm×100 mm， 2.7 μm） was used with 0.1% formic acid aqueous solution （A）-acetonitrile （B） as the mobile phase for gradient elution （0-26 min，2%-18%B； 26-60 min， 18%-72%B； 60-70 min， 72%-100%B； 70-71 min， 100%-2%B； 71-72 min， 2%B）， and the flow rate of 0.4 mL·min-1 and injection volume of 3 μL. The electrospray ionization （ESI） was used in positive and negative modes， and detection range was m/z 50-1 100. The collected data were processed by Agilent MassHunter workstation. According to the retention time and MS information of each compound， combined with existing literature and MS database information， the compounds were identified and analyzed for the fragmentation rule. ResultA total of 52， 55 components were identified in the positive and negative ion modes， respectively. Among them， 14 flavonoids， 3 triterpenoids， 15 organic acids and 20 other compounds were identified under positive ion mode， while 18 flavonoids， 9 triterpenoids， 18 organic acids and 10 other compounds were identified under the negative ion mode. By summarizing the positive and negative ion modes and removing the common compounds， 87 compounds were identified， including 22 flavonoids， 27 organic acids， 11 triterpenoids and 27 other compounds. ConclusionUHPLC-Q-TOF/MS can be used to quickly analyze the chemical constituents in C. paliurus dried leaves. 1-Kestose and 18β-glycyrrhetinic acid and other components related to hypoglycemic activity of this herb are identified for the first time， which can provide reference for clarifying the pharmacodynamic substance basis of C. paliurus dried leaves.

Antimicrobial and antibiofilm activity of the essential oil from dried leaves of Eucalyptus staigeriana / Atividade antimicrobiana e antibiofilme do óleo essencial de folhas secas de Eucalyptus staigeriana

In recent years, compounds with biological properties produced by plants have received attention as an alternative to control microorganisms. Essential oils extracted from green leaves of Eucalyptus sp. have been demonstrated to have antimicrobial activities, but so far there are no reports of antimicrobial activity of essential oils extracted from dried leaves of Eucalyptus staigeriana. So, the objectives of this study were to determine the chemical composition of the essential oils obtained from dried leaves of E. staigeriana (EOdlES) and to evaluate in vitro antimicrobial and antibiofilm activities of EOdlES against gram-positive and gram-negative, resistance and multiresistant Enterococcus faecalis isolated from food and clinical samples. The characterization of EOdlES was performed by gas chromatography-mass spectrometry (GC/MS). For this study, 26 bacterial strains were used, which included 11 reference strains and 15 antibiotic resistant and multiresistant E. faecalis strains. Antimicrobial activities of EOdlES against gram-positive and gram-negative were determined using the disc diffusion method. The minimum inhibitory concentration (MIC) value was evaluated by a microbroth dilution technique. The antibiofilm effects were assessed by microtiter plate method. As a result, 21 compounds were identified, being oxygenated monoterpenes (69.58%) the major chemical family. EOdlES showed only antimicrobial activity against gram-positive strains. E. faecalis resistant and multiresistant strains show the lowest MIC (3.12 to 6.25%), when compared with reference E. faecalis strain. EOdlES has the ability to inhibit the biofilm formation, but little or none ability to inhibit the preformed biofilm. This study demonstrates that EOdlES is a promising alternative to control important foodborne and clinic gram-positive resistant bacteria.(AU)

Nos últimos anos, compostos com propriedades biológicas produzidas por plantas têm recebido atenção como alternativa de controle de micro-organismos. Óleos essenciais extraídos de folhas verdes de Eucalyptus sp. têm demonstrado atividades antimicrobianas. No entanto, até o momento não há nenhum relato de atividade antimicrobiana de óleos essenciais extraídos de folhas secas de Eucalyptus staigeriana. O objetivo deste estudo foi determinar a composição química dos óleos essenciais obtidos de folhas secas de E. staigeriana e avaliar in vitro a sua atividade antimicrobiana e de antibiofilme contra gram-positivas e gram-negativas e também resistentes e multirresistentes de Enterococcus faecalis isolados de amostras de alimentos e clínicas. A caracterização de E. staigeriana foi realizada por CG-EM. Para este estudo foram utilizadas 26 cepas bacterianas, que incluíram 11 cepas referência e 15 cepas de E. faecalis resistentes a antibióticos. A atividade antimicrobiana de E. staigeriana contra gram-positivas e gram-negativas foi determinada utilizando o método de disco-difusão. Os valores da concentração inibitória mínima foram avaliados pela técnica de microdiluição. Os efeitos de antibiofilme foram avaliados pelo método de placa de microtitulação. Como resultado, 21 compostos foram identificados, sendo monoterpenos oxigenados (69,58%) a grande família química. E. staigeriana mostrou apenas atividade antimicrobiana contra cepas gram-positivas. Cepas de E. faecalis resistentes e multirresistentes mostraram a menor concentração inibitória mínima (3,12 para 6,25%) quando comparado com a cepa referência de E. faecalis. E. staigeriana apresentou a capacidade de inibir a formação de biofilme, mas pouca ou nenhuma capacidade de inibir o biofilme pré-formado. Este estudo demonstra que o óleo essencial obtido de folhas secas de E. staigeriana é uma alternativa promissora para controle importante de bactérias gram-positivas resistentes de origem alimentar e clínicas.(AU)

Optimization of the Extraction and Purification Technologies of Total Flavonoids from Diospyros kaki Thunb. Leaves and Comparison of the Contents of Total Flavonoids in Fresh and Dried Diospyros kaki Thunb. Leaves / 中国药房

OBJECTIVE:To optimize the parameters of the extraction and purification technologies of total flavonoids from Di-ospyros kaki Thunb. leaves,and then to compare the contents of flavonoids in fresh and dried D. kaki Thunb. leaves. METHODS:Taking the yield of total flavonoids as the investigated index,the influences of liquid-solid ratio,the volume fraction of ethanol and ultrasonic extraction time on the extraction effect were discussed by single-factor and orthogonal test. With the purity of total flavo-noids as the investigated index,the purification effects of such three kinds of methods as ethyl acetate extraction method,alcohol deposition method and macroreticular resin purification method combined with petroleum ether degreasing on the extracted solution were compared. The optimal extraction technology was adopted to extract the total flavonoids from fresh and dried D. kaki Thunb. leaves and their contents were compared. RESULTS:The optimal extraction technology was as follows as liquid-solid ratio of 25∶1 (ml/g),volume fraction of ethanol of 70%,ultrasonic extraction time of 30 min,extraction temperature of 30 ℃. The results of the verification tests showed the average content of total flavonoids was 1.75%(RSD=2.00%,n=3). The total flavonoids in the extracted solution purified by the above-mentioned three purification methods had a purity of 24.92%,15.94% and 35.52% respec-tively,in which the macroreticular resin purification method with petroleum ether degreasing combined with AB-8 resin purification was optimal. The content of flavonoids in fresh D. kaki Thunb. leaves(1.75%) was about twice as much as that in dried leaves (0.87%). CONCLUSIONS:The optimal extraction and purification technologies are simple with good effect,and suitable for large-scale production. Fresh D. kaki Thunb. leaves should be used as raw materials for extracting flavonoids.