title: Using ITS2 PCR-RFLP to generate molecular markers for authentication of Sophora flavescens Ait.
abstract: BACKGROUND
  Dried root of Sophora flavescens Ait. is a medicinal material occasionally misused or adulterated by other species similar in appearance. In this study the internal transcribed spacer (ITS) regions of DNA samples of S. flavescens Ait. collected from different areas of Taiwan were amplified by polymerase chain reaction (PCR) and compared. The effectiveness of using ITS2 PCR restriction fragment length polymorphism (RFLP)-generated markers to differentiate S. flavescens Ait. from possible adulterants was also evaluated.
  
  
  RESULTS
  The S. flavescens Ait. samples collected from different areas were extremely low in ITS sequence variability at species level. ITS2 PCR-RFLP coupled with restriction enzymes Sac I, Sac II, Xho I or Pvu I produced specific fragments for all tested variants. ITS2 PCR-RFLP coupled with Sac II was further performed to identify mixtures of DNA extracts of S. flavescens Ait. and Sophora tomentosa L. in various ratios. The developed ITS2 PCR-RFLP markers could detect mixed DNA samples of S. flavescens Ait./S. tomentosa L. up to a ratio of 10:1.
  
  
  CONCLUSIONS
  The present study demonstrates the usefulness of ITS2 PCR-RFLP coupled with pre-selected restriction enzymes for practical and accurate authentication of S. flavescens Ait. The technique is also suitable for analysing S. flavescens Ait. mixed with other adulterants.
authors.affiliation: Department of Agronomy, National Chung Hsing University, Taichung, Taiwan, ROC.
authors.forename: Tzu Che
authors.initials: TC
authors.lastname: Lin
authors.forename: Mau Shing
authors.initials: MS
authors.lastname: Yeh
authors.forename: Ya Ming
authors.initials: YM
authors.lastname: Cheng
authors.forename: Li Chang
authors.initials: LC
authors.lastname: Lin
authors.forename: Jih Min
authors.initials: JM
authors.lastname: Sung
mesh_terms: D054458:Amplified Fragment Length Polymorphism Analysis; D001483:Base Sequence; D002681:China; D004262:DNA Restriction Enzymes / Q000378:metabolism; D021901:DNA, Intergenic / Q000737:chemistry / Q000378:metabolism*; D018744:DNA, Plant / Q000737:chemistry / Q000378:metabolism*; D030561:Databases, Nucleic Acid; D004365:Drugs, Chinese Herbal / Q000032:analysis; D005819:Genetic Markers; D029882:Glycyrrhiza uralensis / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D018517:Plant Roots / Q000378:metabolism*; D012150:Polymorphism, Restriction Fragment Length; D015183:Restriction Mapping; D016415:Sequence Alignment; D029909:Sophora / Q000235:genetics* / Q000378:metabolism; D013045:Species Specificity; D013624:Taiwan
chemical_list: D021901:DNA, Intergenic; D018744:DNA, Plant; D004365:Drugs, Chinese Herbal; D005819:Genetic Markers; D004262:DNA Restriction Enzymes