title: Biological activities and safety of Thanaka (Hesperethusa crenulata) stem bark.
abstract: BACKGROUND
  The stem bark powder of Hesperethusa crenulata or Thanaka has been used on the face by Myanmar women for more than a thousand years as a skin care regiment.
  
  
  OBJECTIVE
  The aim of the current study was to both verify the safety and evaluate some biological activities of the Thanaka bark.
  
  
  METHODS
  Maceration of the Thanaka bark powder resulted in hexane, dichloromethane, ethyl acetate, methanol, 85% ethanol and water extracts. For the safety evaluation, cytotoxicity and genotoxicity of each extract were tested. Antibacterial, tyrosinase inhibition, antioxidant and anti-inflammatory activities were evaluated for each extract.
  
  
  CONCLUSIONS
  Extracts from Thanaka bark showed strong anti-inflammatory, significant antioxidation, mild tyrosinase inhibition and slight antibacterial activities. All extracts and the original bark powder showed no detectable genotoxicity while very low cytotoxicity with IC(50) value of more than 12 mg/ml was detected in the water extract. Thus, the use of the Thanaka bark in the form of a watery paste as a skin care regiment is not only safe but also beneficial to skin.
authors.affiliation: Program in Biotechnology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Sakulna
authors.initials: S
authors.lastname: Wangthong
authors.forename: Tanapat
authors.initials: T
authors.lastname: Palaga
authors.forename: Sirirat
authors.initials: S
authors.lastname: Rengpipat
authors.forename: Supason P
authors.initials: SP
authors.lastname: Wanichwecharungruang
authors.forename: Panpilai
authors.initials: P
authors.lastname: Chanchaisak
authors.forename: Michael
authors.initials: M
authors.lastname: Heinrich
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000893:Anti-Inflammatory Agents / Q000032:analysis / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology; D019540:Area Under Curve; D001419:Bacteria / Q000187:drug effects; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004353:Drug Evaluation, Preclinical; D005260:Female; D006801:Humans; D020128:Inhibitory Concentration 50; D008826:Microbial Sensitivity Tests; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors; D009152:Mutagenicity Tests; D024301:Plant Bark / Q000633:toxicity; D010936:Plant Extracts / Q000494:pharmacology* / Q000633:toxicity*; D018547:Plant Stems / Q000633:toxicity; D027821:Rutaceae; D017592:Skin Care
chemical_list: D000900:Anti-Bacterial Agents; D000893:Anti-Inflammatory Agents; D000975:Antioxidants; D010936:Plant Extracts; D014442:Monophenol Monooxygenase