Meili Guo

A novel hepatoprotective saponin from Celosia cristata L.

A new saponin, cristatain (1), together with four other saponins, celosin A (2), celosin B (3), celosin C (4) and celosin D (5) were isolated from the seeds of Celosia cristata L. (Amaranthaceae). Their structures were established by chemical and spectroscopic analyses. For the first time, the saponins were found in C. cristata L. In addition, compound 1 exhibited significant hepatoprotective effect on carbon tetrachloride (CCl(4))- and N,N-dimethylformamide (DMF)-induced hepatotoxicity in mice, which were evidenced by significant decreases in the values of asparate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) of serum and histopathological examinations compared to controls.

Genetic Diversity and Population Structure of Celosia argentea and Related Species Revealed by SRAP

Genetic diversity of 16 populations of Celosia argentea L. and 6 populations of Celosiacristata L. in China was investigated using sequence-related amplified polymorphism (SRAP). Ten SRAP primer combinations generated 507 scorable amplification bands ranging from 50 to 2000 bp, among which 274 were polymorphic, with an average of 54 polymorphic bands per primer combination. The unweighted pair group method of arithmetic averages (UPGMA) cluster analysis enabled construction of a phylogenetic tree for estimating genetic distance among populations, which agreed well with the geographic origin information. Twenty-two populations were distinctly separated into two major genetic groups. One typical representative fragment, M1E6 in C. argentea, provided an alternative approach to distinguish C. argentea from C. cristata. Also, great genetic diversity found in C. argentea populations by significant geographic difference was confirmed by a high level of population genetics parameters. The information may be beneficial to future breeding selection and conservation management for populations of C. argentea.

Identification and Mapping of a Novel Hydroxysafflor Yellow A (HSYA) Biosynthetic Gene in Carthamus tinctorius

The flower of the safflower plant, Carthamus tinctorius L., has been used extensively in traditional Chinese medicine for treatment of cerebrovascular and cardiovascular diseases. Hydroxysafflor yellow A (HSYA) is the main chemical component of the safflower yellow pigments. The potential pharmaceutical effects of HSYA make it an attractive target for genetic engineering strategies aimed at producing plants with higher levels of HSYA and hence increased pharmaceutical value. The cDNA-AFLP method, used extensively in the analysis of transcription profiles in plants (Bachem et al. 1996; Durrant et al. 2000; Milioni et al. 2001; He et al. 2003), is a genomewide expression analysis technology that does not require any prior knowledge of gene sequences (Bachem et al. 1996). Its sensitivity and specificity have been compared to those of a microarray approach (Reijans et al. 2003). It has been demonstrated that cDNA-AFLP combined with a bulked segregant analysis strategy can be very effective and relatively simple in selecting a genomewide display of differentially expressed genes associated with particular phenotypes (Barcaccia et al. 2001; Jun et al. 2006). There are two homozygous mutant species of safflowers, one with an extremely high content of HSYA and the other with no HSYA throughout its life cycle.