Stability-increasing effects of anthocyanin glycosyl acylation.

This review comprehensively summarizes the existing knowledge regarding the chemical implications of anthocyanin glycosyl acylation, the effects of acylation on the stability of acylated anthocyanins and the corresponding mechanisms. Anthocyanin glycosyl acylation commonly refers to the phenomenon in which the hydroxyl groups of anthocyanin glycosyls are esterified by aliphatic or aromatic acids, which is synthetically represented by the acylation sites as well as the types and numbers of acyl groups. Generally, glycosyl acylation increases the in vitro and in vivo chemical stability of acylated anthocyanins, and the mechanisms primarily involve physicochemical, stereochemical, photochemical, biochemical or environmental aspects under specific conditions. Additionally, the acylation sites as well as the types and numbers of acyl groups influence the stability of acylated anthocyanins to different degrees. This review could provide insight into the optimization of the stability of anthocyanins as well as the application of suitable anthocyanins in food, pharmaceutical and cosmetic industries.

Molecular structures of the stem tuber anthocyanins of colored potatoes and their coloring effects on the tubers.

This paper summarized the important achievements about the general characteristics of the molecular structures of the stem tuber anthocyanins of Colored potatoes and the basic coloring effects of the anthocyanins on the tubers. The various coloration patterns of the skins and/or flesh of Colored potato tubers result from the accumulation of the anthocyanins in the periderms, phelloderms and/or peripheral cortices of the tubers, and the tuber colors are fundamentally determined by the matching profiles of the six naturally occurring anthocyanidins, i.e., cyanidin, delphinidin, malvidin, pelargonidin, peonidin and petunidin. Generally, the tuber anthocyanidins hold an O-glycosidic bond-linked rutinosyl at the C3 site, and either a glucosyl linked by an O-glycosidic bond or no substituent group may exist at the C5 site simultaneously. Furthermore, an E-monoacyl frequently exists at the C3-rutinosyls or at the C5-glucosyls of most tuber anthocyanins, and the phenolic acids acylating the tuber anthocyanins are often p-coumaric, ferulic and caffeic acids. The popular names of the p- coumaric acid derivatives of the malvidin, pelargonidin, peonidin and petunidin of the tubers are Malvanin, Pelanin, Peonanin and Petanin, respectively. This review provides a reference for the exploration of the mechanism of the tuber coloration and the identification of the molecular structures of the stem tuber anthocyanins of Colored potatoes.

[Construction and sequence analysis of a normalized full-length cDNA library of Dendrobium officinale].

OBJECTIVE: In order to obtain functional genes, a normalized stems cDNA library was constructed from medicinal plant Dendrobium officinale. METHOD: SMART (switching mechanism at 5' end of RNA transcript) cDNA synthesis combined with DSN (duplex-specific nuclease) normalization was applied to construct the normalized full-length cDNA library of D. officinale. RESULT: The titer of cDNA library was about 1.3 x 10(6) cfu x mL(-1) and the average insertion size was about 1.5 kb with high recombination rate (93.9%). Random selected 163 positive clones were sequenced at single side. Bio-information analysis indicated that 147 from 150 high-quality unique sequences matched corresponding homologous proteins, and they participated in various biological processes based on GO (gene ontology). There were 8 clones with complete coding sequence, which presumed to be full-length genes. CONCLUSION: These results showed preliminarily that we successfully constructed a normalized full-length cDNA library of D. officinale which could be used to screen the functional genes related to metabolic pathways of medicinal ingredients.

[RAPD analysis on genetic relationships of Erigeron breviscapus germplasm resources].

OBJECTIVE: To investigate the genetic relationships of Erigeron breviscapus at the molecular biology level. METHOD: Thirty seven germplasm resources of E. breviscapus which collected from Yunnan, Sichuang and Guizhou province in 2005 were analyzed by Random amplified polymorphic DNA (RAPD) and cluster analysis based on NTSYS2. RESULT: A total of 10 primers were screened, and 107 bands were amplified, among which 94 (87.85%) bands were found to be polymorphic. Thirty seven germplasm resources of E. breviscapus were clustered into 3 groups at genetic distance 0.36, the I group include in 9 germplasm resources collected from Mile, Qiubei, Luxi, Gejiu, and Yanshan of south east of Yunnan province; the II group included 8 germplasm resources collected from Gucheng, and shangrila of north west of Yunnan province, and Mile and Qiubei of south east of Yunnan province; the III group included in 20 germplasm resources collected from the center of Yunnan province, north east of Yunnan province, Sichuan province, and Guizhou province. CONCLUSION: There were abundant genetic diversity in the germplasm resources of E. breviscapus, and the genetic relationships are closely related to geographical distance where they were collected.