Showing papers by "Paul Pui-Hay But published in 2011"

Identification of herbal medicinal materials using DNA barcodes

Abstract: Herbal medicinal materials have been used worldwide for centuries to maintain health and to treat disease. However, adulteration of herbal medicines remains a major concern of users and industry for reasons of safety and efficacy. Identification of herbal medicinal materials by DNA technology has been widely applied, started from the mid-1990s. In recent years, DNA barcoding of global plant species using four standard barcodes (rbcL, matK, trnH–psbA and ITS) has been a major focus in the fields of biodiversity and conservation. These DNA barcodes can also be used as reliable tools to facilitate the identification of herbal medicinal materials for the safe use of herbs, quality control, and forensic investigation. Many studies have applied these DNA barcodes for the identification of herbal medicinal species and their adulterants. The present article reviews efforts in the identification of herbal medicinal materials using the standard DNA barcodes and other DNA sequence-based markers.

Application of DNA barcodes in Hedyotis L. (Spermacoceae, Rubiaceae)

Abstract: The potential application of DNA barcodes of plastid (matK, trnH–psbA, petD, and rbcL) and nuclear (internal transcribed spacer (ITS) of rDNA) DNA regions was investigated for 25 Hedyotis taxa The ITS showed the best species discrimination by resolving 23 of the species as exclusive lineages with no shared alleles between any of the 24 distinct species (H assimilis and H mellii are not supported as distinct species based on our molecular and morphological data) Conversely, rbcL performed the worst and only resolved 10 of the species as exclusive lineages, and 10 species with shared alleles Using ITS has the advantage of high PCR amplification success and it provides good intra- and interspecific variation distribution patterns The most powerful plastid markers were petD and trnH–psbA, but we could amplify and sequence trnH–psbA for only 83% of the accessions sampled Combination of ITS and petD performed extremely well, with all 24 of the distinct species resolved as exclusive lineages and no shared alleles between any of the distinct species We therefore recommend ITS, or a combination of ITS and petD, as the standard DNA barcode in Hedyotis, but acknowledge that there are no shared alleles between distinct species for matK and rbcL combined

Forensically informative nucleotide sequencing (FINS) for the authentication of Chinese medicinal materials

Abstract: Chinese medicinal materials may be authenticated by molecular identification. As a definitive approach to molecular identification of medicinal materials, forensically informative nucleotide sequencing (FINS) comprises four steps, namely (1) DNA extraction from biological samples, (2) selection and amplification of a specific DNA fragment, (3) determination of the sequence of the amplified DNA fragment and (4) cladistic analysis of the sample DNA sequence against a DNA database. Success of the FINS identification depends on the selection of DNA region and reference species. This article describes the techniques and applications of FINS for authenticating Chinese medicinal materials.