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Introduction: Tiliacora triandra (F. Menispermaceae) is edible and is also known for medicinal values. The leaves are a popular flavoring in Southeast Asia, especially in the northeast of Thailand. The objectives of this study were to determine the major constituents of the leaves of T. triandra, and assess their anticancer activities against human cancer cell lines. Methods: The leaves were extracted by a soxhlet apparatus with petroleum ether, dichloromethane, ethyl acetate and water. Major constituents were then purified and identified using chromatographic procedures and various spectroscopic techniques. In vitro anticancer activity tests of T. triandra extracts were performed by resazurinmicroplate assay (REMA), and tested with 3 cell lines: oral cavity cancer (KB), lung cancer (NCI-H187) and breast cancer (MCF-7) cell lines. Results: The result indicated that the main compound of T. triandra leaves was oxoanolobine. The methanol extract showed the highest cytotoxic activity against lung cancer (NCI-H187) cell line whereas the water extract exhibited the highest activity against oral cavity cancer (KB) cell line. The IC 50 of oxoanolobine against the NCI-H187 cell line was 27.60 ± 4.30 µg/mL. Conclusion: T. triandra leaves contain oxoanolobine as the major constituent and have the potential of anticancer activity but are required to be investigated further.

Antibacterial activity against veterinary Salmonella was determined using dried fruit extracts of Ardisia elliptica Thunb. Chromatographic purification and spectroscopic structure studies provided three active anti-Salmonella compounds, namely, syringic acid, isorhamnetin and quercetin. The minimal inhibitory concentrations (MICs) of the isolated compounds ranged between 15.6 and 125.0 microg mL(-1).

Introduction: Skin darkness may be cosmetically undesirable for some people. Plant-derived materials traditionally used for skin lightening may produce satisfactory results. Besides innate tyrosinase activity, oxidative stress also plays an important role in skin darkness by activating tyrosinase. Therefore, herbal extracts with strong anti-tyrosinase and antioxidant activities could be considered as efficacious skin lightening agents. The aims of the present study were to determine the anti-tyrosinase and antioxidant activities of Thai medicinal plant extracts indigenously used as skin toners. Methods: The activities of seven Thai medicinal plants; Zingiber cassumunar Roxb., Phyllanthus emblica Linn., Tagetes erecta Linn., Centella asiatica, Raphanus sativusvar. Longipinnatus Linn., Cassia fistula Linn. and Butea monosperma (Lam.) Taub. were investigated using the DOPA-chrome method to determine anti-tyrosinase activity and the DPPH free radical scavenging assay to determine antioxidant activity. Results: With respect to tyrosinase inhibitory activity, P. emblica, B. monosperma and R. sativusvar. Longipinnatus extracts at a concentration of 1.67 mg/mL showed strong activities with the percentage of tyrosinase inhibition at 48.38±4.77, 46.92±3.77 and 42.85±6.54%, respectively. In addition, P. emblica and B. monosperma extracts also exhibited high antioxidant activities with the IC 50 values on 33.47±1.24 and 33.57±1.92 mg/mL, respectively. Conclusion: Based on tyrosinase inhibition activity and DPPH radical scavenging assays, the herbal extracts of P. emblica and B. monosperma show promise as potential skin lighteners in cosmetic formulations.

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