OBJECTIVEThis study examined the antimicrobial activity of Cannabis sativa, Thuja orientalis and Psidium guajava against methicillin-resistant Staphylococcus aureus (MRSA) and used a standardized purification protocol to determine the presence and abundance of bioactive compounds in the leaf extracts.

METHODSIn vitro antimicrobial activities of the ethanolic extracts of C. sativa, T. orientalis and P. guajava were tested against MRSA. The presence of bioactive molecules in these three leaves was evaluated using biochemical assays and high-performance thin-layer chromatography (HPTLC).

RESULTSResistance to methicillin, penicillin, oxacillin and cefoxitin was observed in each of the clinical and nonclinical MRSA isolates. However, they were still vulnerable to vancomycin. Used individually, the 50% extract of each plant leaf inhibited MRSA growth. A profound synergism was observed when C. sativa was used in combination with T. orientalis (1:1) and when P. guajava was used in combination with T. orientalis (1:1). This was shown by larger zones of inhibition. This synergism was probably due to the combined inhibitory effect of phenolics present in the leaf extracts (i.e., quercetin and gallic acid) and catechin, as detected by HPTLC.

CONCLUSIONThe leaf extracts of C. sativa, T. orientalis and P. guajava had potential for the control of both hospital- and community-acquired MRSA. Moreover, the inhibitory effect was enhanced when extracts were used in combination.

Anti-Bacterial Agents ; pharmacology ; Cannabis ; Drug Resistance ; drug effects ; Humans ; Methicillin ; pharmacology ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; growth & development ; Microbial Sensitivity Tests ; Phytotherapy ; Plant Extracts ; pharmacology ; Plant Leaves ; Psidium ; Staphylococcal Infections ; drug therapy ; microbiology ; Thuja

OBJECTIVESThis study aimed to evaluate the in vitro antioxidant capacity, to determine the anti-inflammatory effect due to lipoxygenase inhibition and to test the antimicrobial activity of ethanolic extracts from leaves of seven climbing species belonging to the Bignoniaceae family. These species are Adenocalymma marginatum (Cham.) DC., Amphilophium vauthieri DC., Cuspidaria convoluta (Vell.) A. H. Gentry, Dolichandra dentata (K. Schum.) L. G. Lohmann, Fridericia caudigera (S. Moore) L. G. Lohmann, Fridericia chica (Bonpl.) L. G. Lohmann and Tanaecium selloi (Spreng.) L. G. Lohmann.

METHODSThe antioxidant activity was evaluated using three methods, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ferric reducing antioxidant power. Lipoxygenase-inhibiting activity was assayed spectrophotometrically; the result was expressed as percent inhibition. The antimicrobial activity was assessed using the agar disk diffusion method. Minimal inhibitory concentration (MIC) and minimal bactericidal/fungicidal concentration were also determined for each extract against 12 pathogenic bacterial strains of Staphylococcus aureus and seven fungal strains of the Candida genus. The identification of the major compounds present in the most promising extract was established by high-performance liquid chromatography-tandem mass spectrometry.

RESULTSC. convoluta, F. caudigera, and F. chica exhibited the best antioxidant activity by scavenging DPPH and ABTS radicals and reducing Fe ion. These extracts showed a notable inhibition of lipoxygenase. F. caudigera was found to have the lower MIC value against S. aureus strains and six Candida species. The extracts of F. caudigera and C. convoluta were active even against methicillin-resistant S. aureus. C. convoluta had higher total phenol content, better antioxidant activity and superior anti-inflammatory and antimicrobial activity. The main phenolic compounds found in this extract were coumaric and hydroxybenzoic acid derivatives and glycosylated and nonglycosylated flavones.

CONCLUSIONMost of the extracts exhibited antioxidant activity as well as in vitro inhibition of lipoxygenase. The excellent antimicrobial activity of T. selloi and F. chica supports their use in traditional medicine as antiseptic agents. The extracts of F. caudigera and C. convoluta, both with notable biological activities in this study, could be used as herbal remedies for skin care. In addition, this study provides, for the first time, information about phenolic compounds present in C. convoluta.

Anti-Infective Agents ; chemistry ; pharmacology ; Antioxidants ; chemistry ; pharmacology ; Bignoniaceae ; chemistry ; Candida ; drug effects ; growth & development ; Humans ; Lipoxygenase ; chemistry ; Lipoxygenase Inhibitors ; chemistry ; pharmacology ; Medicine, Traditional ; Microbial Sensitivity Tests ; Plant Extracts ; chemistry ; pharmacology ; Staphylococcus aureus ; drug effects ; growth & development

Three new alkyl substituted anthraquinone derivatives, trivially named as symploquinones A-C (Compounds 1-3) were isolated from Symplocos racemosa. The structures of these compounds were determined on the basis of extensive spectroscopic analyses (UV, IR, Mass, H- and C-NMR, and two-dimensional (2D) NMR techniques). The resulting data were also compared with the reported literature. These compounds were then subjected to antibacterial or antibiofilm testing. Compounds 1 and 3 exhibited good antibacterial activity in the concentration range of 160-83 μg·mL against Streptococcus mutans, methicillin resistant Staphylococcus aureus and Proteus mirabilis. Both compounds were further screened for anti-biofilm activity, which revealed promising activities at sub-MIC concentrations. None of the compounds were found to be active against Klebsiella pneumoniae.
Anthraquinones ; chemistry ; isolation & purification ; pharmacology ; Anti-Bacterial Agents ; chemistry ; isolation & purification ; pharmacology ; Biofilms ; drug effects ; growth & development ; Ericales ; chemistry ; Magnetic Resonance Spectroscopy ; Mass Spectrometry ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; physiology ; Microbial Sensitivity Tests ; Proteus mirabilis ; drug effects ; physiology ; Spectrophotometry, Infrared ; Streptococcus mutans ; drug effects ; physiology

This study aimed to develop a guideline for therapeutic drug monitoring (TDM) of vancomycin. We adopted the new guideline definition from the Institute of Medicine (IOM), adhered closely to the six domains of the Appraisal of Guidelines for Research & Evaluation II (AGREE II), and made recommendations based on systematic reviews. We established a Guideline Steering Group and a Guideline Development Group, formulated 12 questions in the form of Population, Intervention, Comparison, Outcome (PICO) and completed a literature search. As far as we know, we will develop the first evidenced-based guideline for vancomycin TDM under the framework of the Grade of Recommendations Assessment, Development and Evaluation (GRADE).
Anti-Bacterial Agents ; administration & dosage ; economics ; pharmacokinetics ; China ; Drug Administration Schedule ; Drug Monitoring ; methods ; Evidence-Based Medicine ; Humans ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; growth & development ; pathogenicity ; Staphylococcal Infections ; drug therapy ; microbiology ; pathology ; Vancomycin ; administration & dosage ; economics ; pharmacokinetics

OBJECTIVETo study the effect of DNase I on biofilm formation of Staphylococcus aureus.

METHODSThe growth curve of S. aureus was detected using a spectrophotometer. The adhesion of S. aureus was analyzed using flat colony counting method, and the biofilm formation was assayed using the 96-well crystal violet staining method.

RESULTSExposure to different concentrations of DNase I did not obviously affect the growth of S. aureus but significantly inhibit the formation of bacterial biofilms in a dose-dependent manner. DNase I inhibited the adhesion of S. aureus at different growth stages. When combined with antibiotics, DNase I resulted in a signi?cant decrease in the established bio?lm biomass compared to antibiotics or DNase I used alone.

CONCLUSIONDNase I can effectively inhibit biofilm formation of S. aureus and enhance the inhibitory effect of antibiotics against S. aureus biofilms.

Anti-Bacterial Agents ; Biofilms ; drug effects ; Deoxyribonuclease I ; chemistry ; Staphylococcus aureus ; growth & development

Isolated alkaloids from Coptis chinensis Franch. The compounds were identified as berberine, columbamine, groenlandicine, jatrorrhizine, magnoflorine, corydaldine and ferulic acid methylester. Then measured their bitter degree based on the electronic tongue and evaluated the antibacterial. The results based on the Electronic Tongue showed that berberine, columbamine, groenlandicine and jatrorrhizine have higher bitter degree than magnoflorine and corydaldine. And they also appeared better antibacterial activity on E. coli and S. aureus. The correlation coefficients between bitter degree and the two bacteria antibacterial activity were 0.983 and 0.911. So there was close relationship between the bitter degree and antibacterial activity of bitter components. Thus, it is confirmed further that bitter components are the material foundation of medicinal effectiveness of bitter herbs.
Aporphines ; analysis ; Berberine ; analogs & derivatives ; analysis ; Berberine Alkaloids ; analysis ; Biomedical Research ; instrumentation ; methods ; Coptis ; chemistry ; Drugs, Chinese Herbal ; analysis ; chemistry ; pharmacology ; Electronics ; instrumentation ; methods ; Escherichia coli ; drug effects ; growth & development ; Microbial Sensitivity Tests ; Reproducibility of Results ; Staphylococcus aureus ; drug effects ; growth & development ; Taste

AIM: Methicillin-resistant Staphylococcus aureus (MRSA) is a pathogenic bacterium that causes both hospital- and community-acquired infections, and for which single-drug treatments are becoming less efficient. Rhizoma coptidis has been used for more than two thousand years in China to treat diarrhea, fever, and jaundice. In this study, the anti-MRSA activity of Rhizoma coptidis is examined and its effective components sought. METHODS: The mecA and norA genes were determined by PCR amplification and sequencing. Drug susceptibility of Staphylococcus aureus ATCC43300 was performed using the VITEK2 compact system. The chemical fingerprint of Rhizoma coptidis was investigated using HPLC and preparative liquid chromatography, and the anti-MRSA activity was determined using an improved broth microdilution method. RESULTS: The drug susceptibility test revealed that the penicillin-binding protein phenotype of the strain changed in comparison to penicillin-sensitive Staphylococcus aureus. Ten batches of Rhizoma coptidis showed anti-MRSA activity on the norA-negative Staphylococcus aureus strain, as well as the strain that contained a norA gene. The spectrum-effect relationship revealed that the berberine alkaloids were the effective components, within which berberine, coptisine, palmatine, epiberberine, and jatrorrhizine were the major components. CONCLUSION This study lays a foundation for in vivo studies of Rhizoma coptidis and for the development of multi-component drugs.
Anti-Bacterial Agents ; chemistry ; pharmacology ; Bacterial Proteins ; genetics ; metabolism ; China ; Drugs, Chinese Herbal ; chemistry ; pharmacology ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; genetics ; growth & development ; metabolism ; Microbial Sensitivity Tests ; methods ; Ranunculaceae ; chemistry ; Rhizome ; chemistry

Biofilms are communities of surface-associated bacteria or fungi embedded in a self-produced extracellular polymeric matrix that are notoriously difficult to be eradicated and are sources of many recalcitrant infections. Treatment for biofilm infection with any individual drug is always less effective, while the combinations of different types of drugs are superior to monotherapy concerning the removing of biofilms. This paper focus on research progress in recent years for synergistic effect of drugs in combination against biofilms formed by Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Candida albicans.
Anti-Bacterial Agents ; pharmacology ; Antifungal Agents ; pharmacology ; Bacteria ; drug effects ; Biofilms ; drug effects ; growth & development ; Candida albicans ; drug effects ; Escherichia coli ; drug effects ; Pseudomonas aeruginosa ; drug effects ; Staphylococcus aureus ; drug effects ; Staphylococcus epidermidis ; drug effects

This paper is to report the investigation on the metabolic behavior of Staphylococcus aureus (S. aureus) after given Qingkailing injection, and with the aim of seeking for a new quality control method based on biological assessment. The growth thermogenic curves of S. aureus were determined by microcalorimetry and analyzed by computer. The results showed that in the concentration range of (0-5.00%), the growth thermogenic curves of S. aureus were declined and removed back with increasing dosage of Qingkailing injection; the main parameters (T1, T2, k1, P1, P2 and I) and the dosage of Qingkailing injection have good correlation. The 50% inhibiting dosage is 3.26 %, and the optimal inhibiting dosage is 5.47%. Difference could be detected among the Qingkailing injection samples from different factories and different batches. It is proved that Qingkailing injection could inhibit the metabolic behavior of S. aureus, and microcalorimetry might be applied in the quality assessment of Qingkailing injection.
Calorimetry ; methods ; Dose-Response Relationship, Drug ; Drug Combinations ; Drugs, Chinese Herbal ; administration & dosage ; isolation & purification ; pharmacology ; Plants, Medicinal ; chemistry ; Quality Control ; Staphylococcus aureus ; drug effects ; growth & development ; metabolism ; Thermodynamics

Through our pre-investigation and literature analysis, it was found that rhubarb could be categorized into two types, chrysophanol-type and rhein-type, based on the proportion of the two constituents in the total content of anthraquinones after acid hydrolysis. In this paper, the antimicrobial activities of chrysophanol-type and rhein-type rhubarbs against Staphylococcus aureus were compared with microcalorimetric analysis, in order to illustrate the bioactive differentiability between the two chemotypes. For the aim to display the distinction of chrysophanol and rhein percentage in total anthraquinones, the sampling volume was regulated to make the total anthraquinones equivalent, thus, the antimicrobial difference was only attributed to the difference of chemotypes. The results indicated that the antimicrobial difference between the two chemotypes was confirmable labeled at the biothermokinetic parameters of S. aureus growth affected by the rhubarb samples. The growth rate constant (k1) of the first exponential phase for the growth of S. aureus affected by the rhein-type rhubarb was significantly lower than that of chrysophanol-type (P<0.01), which suggested stronger antimicrobial activity of rhein-type rhubarb than that of chrysophanol-type. However, the antimicrobial activities of rhein-type rhubarbs were not positively correlated to the contents of rhein. It suggested that the antimicrobial activity of rhubarb might be related to some unknown components which were of same accumulating pattern of rhein. The findings in present study provided some experimental evidence on categorizing rhubarb into two chemotypes through the difference of antimicrobial activity on S. aureus by microcalorimetric analysis and, further, offered references to revision of the commercial specification of rhubarb from chemical view.
Anthraquinones ; isolation & purification ; pharmacology ; Anti-Infective Agents ; isolation & purification ; pharmacology ; Calorimetry ; Plants, Medicinal ; chemistry ; Rheum ; chemistry ; Staphylococcus aureus ; drug effects ; growth & development