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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]

Phellodendron amurense Rupr. bark extracts were examined for antioxidant activity, antimicrobial activity and antiviral activity on herpes simplex virus type 1 (HSV-1). Ethanol extract showed higher content of both total phenolic and flavonoid than aqueous extract. In DPPH (2, 2-diphenyl-1-picrylhydrazyl) assay, the concentration providing 50% inhibition (IC50) values were 6.73 ± 0.87 mg/ml and 4.26 ± 0.59 mg/ml for aqueous and ethanol extracts respectively. Ethanol extract had a much higher antimicrobial activity than aqueous extract. Furthermore, the antiviral activity of the ethanol extract on HSV-1 was also tested. The maximum noncytotoxic concentration was 44.12 μg/ml for RC-37 cells. Plaque formation was inhibited by 74±6% when HSV-1 was pretreated with the extract prior to adsorption, whereas pretreatment of the cells with the extract, added during adsorption or after the adsorption only exhibited above 10% antiviral effect. This study has to some extent validated the medicinal potential of P. amurense bark. [ABSTRACT FROM AUTHOR]

Abstract: Applicability of solvent-free microwave extraction (SFME) for extraction of the fruits of Schisandra chinensis essential oil was examined; the composition and antioxidant activities and antibacterial activities of the essential oil were assessed in vitro. An orthogonal experiment (L9 (3)4) was applied to optimize the extraction process. The optimum conditions were: extraction time, 45 min; microwave power, 800 W; diameter of powder particles, 0.25 mm; and proportion of water pretreatment, 30%. Under these conditions, the extraction yield was 1.75%. Thirty-five compounds, representing 91.12% of the oil, were identified, of which the major ones, ylangene (50.11%), β-himachalene (10.76%)，α-bergamotene (9.52%) and β-Chamigrene (5.41%), accounted for of 75.80% the oil. Antioxidant activity, IC50 value of the essential oil was determined as 3.87 mg/mL by DPPH assay, and the inhibition values of the essential oil at 1.8 mg/mL was 41.88% by β-Carotene–linoleic acid bleaching assay. The essential oil was screened for antibacterial activity against both Gram positive (Staphylococcus epidermidis, Staphylococcus aureus, Bacillus subtilis) and Gram negative (Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris) bacteria. The essential oil showed antibacterial effect against all the gram (+) bacteria and gram (−) bacteria tested. These results show that S. chinensis essential oil could be considered as a natural alternative to food antioxidants and preservatives. [Copyright &y& Elsevier]