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In this study, the aqueous and ethanolic extracts (leaves, stems and fruits) from Morus alba L., a traditional Chinese medicine, were evaluated for their antioxidant and antimicrobial properties. Ethanolic extracts showed higher contents of both total phenolics and flavonoids than aqueous extracts. The total phenolic content was in the order of: leaf extracts > fruit extracts > stem extracts, whereas the total flavonoids was: leaf extracts > stem extracts > fruit extracts. Using DPPH assays, the concentrations providing 50% inhibition (IC50) values of aqueous extracts from leaves, stems and fruits were 7.11 ± 1.45 mg/ml, 86.78 ± 3.21 mg/ml and 14.38 ± 2.83 mg/ml, respectively, whereas the IC50 values of ethanolic extracts were 3.11 ± 0.86 mg/ml, 14.62 ± 2.45 mg/ml and 12.42 ± 2.76 mg/ml, respectively. In sum, the antioxidant activities of ethanolic extracts from M. alba L. were stronger than the aqueous extracts, and in the order of: leaf extracts > fruit extracts > stem extracts. The ethanolic extracts exhibited moderate antimicrobial activities, whereas the aqueous extracts showed poor antimicrobial properties in our test system. This study validated the medicinal potential of M. alba L. [ABSTRACT FROM AUTHOR]

Antimicrobial and in vitro anti-tumor activities of Melaleuca alternifolia (tea tree) oil (TTO) were analyzed. The results indicated that TTO possessed significant antimicrobial activity towards all tested microorganisms except Aspergillus niger. The minimum inhibitory concentration (MIC) of TTO towards Staphylococcus epidermidi, Bacillus subtilis, Escherichia coli and Candida albicans was 0.25% (v/v). Time kinetic experiments showed that Staphylococcus epidermidi, Escherichia coli and Candida albicans were completely killed after exposure to TTO at 2× MIC for 1, 4 and 8 h, repectively. TTO also exhibited strong cytotoxicity towards human lung cancer cell line (A549), human breast cancer cell line (MCF-7) and human prostate cancer cell line (PC-3). The IC50 values obtained were 0.012% (v/v), 0.031% (v/v) and 0.037% (v/v), respectively. Flow cytometric analysis demonstrated that TTO restrained the cell cycle progression of PC-3 and MCF-7 cell lines at the G0/G1 phase and A549 cell at the S phase. [ABSTRACT FROM AUTHOR]

This study provided a facile, one-step hydrothermal method to synthesize stable Ag colloid in aqueous solution by utilizing chitosan as both reductant and stabilizer. The formation of chitosan-functionalized Ag nanoparticles was verified by UV–Vis, FTIR, TEM, AFM and XRD measurements. FTIR results revealed that the primary amine groups and amide groups of chitosan have specific interactions with the surface of Ag nanoparticles. The average diameter of the Ag nanoparticles is 10.0 ± 5.4 nm as determined by TEM. Ag nanoparticles are highly crystalline as revealed by HR-TEM and XRD measurements. The size and shape of Ag nanoparticles are also found to depend on the pH condition in the synthesis. Ag nanoparticles were the main products at pH 5.0 whereas large Ag nanotriangle and truncated triangular nanoplate were dominant at pH 4.0 in the synthesis. Due to its monodispersity and good stability, the chitosan-functionalized Ag colloid synthesized at pH 5.0 was further tested for its antibacterial activities against gram-positive bacteria, gram-negative bacteria and fungus. The results of zone of inhibition, inhibition ratio and SEM characterization revealed that chitosan-functionalized Ag nanoparticles have great bactericidal efficiency against both bacteria and fungus. [ABSTRACT FROM AUTHOR]

Water decoctions from the leaves of Taxus cuspidata are used in traditional Chinese medicine to treat cancer, suggesting that water soluble constituents from these leaves may possess anticancer properties. Interestingly, hydrophilic paclitaxel derivatives, as opposed to paclitaxel itself, can be detected by high pressure liquid chromatography in water decoctions from these leaves. The remainder extracts, which are free of paclitaxel and hydrophilic paclitaxel derivatives, from the T. cuspidata leaves were investigated for antitumor activity in vivo and in vitro for the first time in this study. EE80B, 7-xylosyl-10-deacetylpaclitaxel and 7-xylosyl-10-deacetylpaclitaxel C displayed the most antitumor activity in vivo. However, in vitro studies with tumor cell lines showed that EE80B had a significantly smaller antitumor effect than paclitaxel. We hypothesize that water decoctions from T. cuspidata leaves exhibit antitumor effects in vivo, which may be aided by the activation of specific host mechanisms (e.g. stimulation of antitumor immunity) which are not present in vitro. [ABSTRACT FROM AUTHOR]