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

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. © 2011 Li et al; licensee BioMed Central Ltd.published_or_final_versio

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field

Differentiation of Lycium barbarum from its related Lycium species using random amplified polymorphic DNA

The RAPD (random amplified polymorphic DNA) technique was applied for the first time to distinguish Lycium barbarum from other closely related species of the same genus. In this study, eight samples were collected, including five species, two varieties and one cultivated variety. A total of fifty arbitrary primers were used in the RAPD analysis. Distinctive DNA fingerprints corresponding to different Lycium species were successfully obtained from ten primers. Similarity index (S.I.) analysis revealed that the values are higher between intraspecies than interspecies. These results confirmed that the RAPD technique can be employed for distinguishing closely related species of Lycium.link_to_subscribed_fulltex

Isolation of a mitogenic agglutinin with relatively high thermostability from seeds of the variegated shell ginger

An agglutinin with a molecular mass of 130 kDa has been isolated from the seeds of Alpinia zerumbet cv.'Variegata'. The isolation procedure involved anion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, and gel filtration by fast protein liquid chromatography on Superdex 75. The agglutinin exhibited hemagglutinating activity toward rabbit erythrocytes which could not be inhibited by simple sugars. It was composed of four identical 32-kDa subunits with substantial N-terminal sequence similarity to chitinase and yieldin. The hemagglutinating activity of A. zerumbet agglutinin was stable up to 80°C and not affected by presence of a variety of salts. The agglutinin stimulated [methyl- 3H]-thymidine uptake by mouse splenocytes. It did not exhibit antifungal activity. © 2010 Bentham Science Publishers Ltd.link_to_subscribed_fulltex

A DNA microarray for differentiation of the Chinese medicinal herb Dendrobium officinale (Fengdou Shihu) by its 5 S ribosomal DNA intergenic spacer region

A DNA microarray was constructed for high-throughput identification of the plant resource of commercial FDSH [Fengdu Shihu (Dendrobium officinale)]. The 5 S rDNA (ribosomal DNA) intergenic spacer region in D. officinale, D. nobile, D. moniliforme, D. hercoglossum, D. williamsonii, D. capillipes, D. wilsonii and D. jenkinsii was amplified by a single primer pair and sequenced. The sequences showed polymorphism. They were incorporated on a glass slide and hybridized with fluorescently labelled 5 S sequences from commercial Shihu. The DNA microarray enabled the differentiation of D. officinale from the other species tested. FDSH could thus be distinguished from its adulterants. It is evident that DNA microarrays provide a high-throughput and reliable approach for the identification of plant resources, and the method presented here is useful for the authentication of FDSH. © 2008 Portland Press Ltd.link_to_subscribed_fulltex

Application of SCAR (sequence characterized amplified region) analysis to authenticate Lycium barbarum (wolfberry) and its adulterants

Fructus Lycii (Gouqizi) is well known in Chinese herbal medicine for its restorative function of benefiting the liver and kidney, replenishing vital essence and improving eyesight. However, ten species and varieties of Lycium have benn found to be substitutes or adulterants of Lycium barbarum (wolfberry) in commercial markets in the Hong Kong Special Administrative Region and in China generally. L. barbarum cv. 'Tianjinense' and Lycium chinense var. potaninii are the most common examples. It is difficult to differentiate among the Lycium species by traditional morphological and histological analyses. An easy and reliable approach based on SCAR (sequence characterized amplified region) analysis was developed in the present study to differentiate L. barbarum from other Lycium species. Two characteristic bands of approx. 700 and 650 bp were detected on the RAPD (random amplification of polymorphic DNA) profiles generated from samples of L. barbarum and L. chinense var. potaninii using the primer OPC-7. They were isolated and sequenced. Two primer sets, based on the sequences, could amplify a single specific band in samples of L. barbarum respectively, whereas no bands were detected in samples of L. chinense var. potaninii. The results confirmed that the SCAR technique can be employed for authenticating L. barbarum and its adulterants. © 2008 Portland Press Ltd.link_to_subscribed_fulltex