Chaetomadramines A-E, a class of siderophores with potent neuroprotective activity from the fungus Chaetomium madrasense cib-1.

Five hydroxamate siderophores, chaetomadramines A-E (1-5), along with seven known compounds were isolated from the fermented rice culture of the fungus Chaetomium madrasense cib-1. Compounds 1-5 were structurally elucidated on the basis of spectroscopic data, which were a group of unusual hydroxamate siderophores, bearing a long fatty acyl on the α-NH2 of the Nδ-hydroxylated ornithine. Compounds 2-5 were new. The structural elucidation and spectroscopic data of 1 were reported for the first time. Compounds 2-4 significantly improved the survival rates of PC12 cells in the neuroprotective activity assay at the concentration of 40 µM.

Differential Expression of Genes Involved in Saikosaponin Biosynthesis Between Bupleurum chinense DC. and Bupleurum scorzonerifolium Willd.

Radix Bupleuri (roots of Bupleurum spp.) is an important medicinal herb. Triterpenoid saponins of saikosaponins generally constitute the main class of secondary metabolites of plants in the Bupleurum genus. However, the molecular regulatory mechanism underlying their biosynthesis remains elusive. In this study, we observed significantly different saikosaponin biosynthesis between Bupleurum chinense and Bupleurum scorzonerifolium at the seedling stage. The sequential and expression characterization of 232 genes in the triterpenoid saponin biosynthetic pathway, which includes the mevalonate (MVA) pathway and methylerythritol phosphate (MEP) pathway, between B. chinense and B. scorzonerifolium was also investigated. Sixty of these genes may be involved in saikosaponin biosynthesis. Manipulation of these genes, especially those of the ß-AS, P450, and UGT families, may improve saikosaponin production.

The contribution of photosynthesis traits and plant height components to plant height in wheat at the individual quantitative trait locus level.

Plant height is an important agronomic trait for morphogenesis and grain yield formation in wheat. In this study, we performed both normal and multivariate conditional quantitative trait locus (QTL) analyses for plant height with spike length, internode number, length of the first internode to the sixth internode from the top during harvest, and photosynthesis traits at the seedling stage and heading stage based on a recombinant inbred line population. A total of 49 normal QTLs were detected, as well as 312 conditional QTLs. The genetic region Xbcd1970-Xbcd262 on chromosome 2D harbored the most QTLs, with 6 normal QTLs and 39 conditional QTLs. A comparison between the normal and conditional QTL mapping analyses suggested that the length of the third internode, fourth internode, and fifth internode from the top showed a high genetic association with plant height, whereas all photosynthesis traits showed weaker associations. This comparative analysis could serve as a platform for dissecting the genetic relation between objective traits and other phenotypic traits before manipulation of genes collocated with QTL clusters.

Preparation of melanin from Catharsius molossus L. and preliminary study on its chemical structure.

A great deal of melanin was found in the waste alkali liquor produced by extraction of chitin from Catharsius molossus L. Discarding the lye could harm the environment and cause waste of resources. In this paper, melanin from C. molossus L. was recovered through acid precipitation and purified by pepsin and so on. The purity, chemical composition and structure of the prepared melanin were explored by UV-visible absorption spectroscopy, Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, high resolution (13)C Cross polarization magic angle spinning nuclear magnetic resonance spectroscopy pyrolysis gas chromatography mass spectrometry, X ray diffraction, X ray fluorescence, matrix-assisted laser desorption/ionization time of flight tandem mass spectrometry, thermal analysis, and so on. The results showed that the purity of the prepared melanin was higher than the commercial standard melanin and it was a kind of nanoaggregates composed of a large quantity of 5,6-dihydroxyindole eumelanin and a small amount of phaeomelanin. In addition, the prepared melanin was irregular in shape and its structure could be divided into three levels: advanced structure maintained by polypeptides, substructure maintained by the ferric ion and microstructure. In particular, the smallest structural unit showed the graphite-like layered structure containing five layers linked by non-covalent bonds and each layer mainly consisted of 5,6-dihydroxyindole and its derivatives, which might be connected to each other through various chemical bonds.

[Extraction technology of diester-type alkaloids from Radix Aconiti lateralis].

OBJECTIVE: To determine the suitable extraction technology of diester-type alkaloids, such as mesaconitine, aconitine and hypaconitine from the roots of Aconitum carmichaeli (Radix Aconiti lateralis). METHODS: The contents of mesaconitine, aconitine and hypaconitine were determined by HPLC. Single-factor experiment was used to study the extraction factors. RESULTS: The suitable extraction technology for diester-type alkaloids was as follows: coarse sizings of Radix Aconiti lateralis was extracted by 10 times ethanol for 3 times (each time for 1 day) at 15 degrees C. The total yield of diester-type alkaloids was 0.57%, including 0.16% aconitine, 0.032% mesaconitine and 0.38% hypaconitine, and the purity was 18.81%. CONCLUSION: The extraction technology is efficient, harmfulless, economical, convenient and can be used for industrial production.

[Extraction and antioxidant activity of flavonoids from Aralia cordata].

In this study, microwave-assisted extraction techniques of flavonoids fom Aralia cordata were studied by the single factor analysis and orthogonal test, then the property antioxidant activities of flavonoids extracts were evaluated by two antioxidant assays, for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals scavenging and reducing power. The results showed that the optimum conditions were as follows: twice extracting Aralia cordata with 75 times volume (V/W) of 30% ethanol at 140W of microwave for 60 min at 80 degrees C. Under these conditions, the extraction yield was 1.35%. The flavonoids extracts could significantly scavenge DPPH and superoxide anion free radicals in dose-dependent manner, meanwhile a linear correlation between its concentration and reducing power was also observed (R2 = 0.9855).

[Study on quality changes of Radix Aconiti Lateralis Praeparata under different storage conditions].

OBJECTIVE: To analyze the changes of the content of water, soluble protein, total alkaloids, polysaccharides of Radix Aconiti Lateralis Praeparata under different storage treatments. METHODS: The experiment was conducted in 4 kinds of storage methods, such as sack storage, sand storage, cold storage, and the natural heap as the control. RESULTS: During storage, the content of water, total alkaloids and polysaccharides tended to decline, while the content of soluble protein increased. CONCLUSION: Compared with the others, the cold storage is most suitable for keeping good quality of Radix Aconiti Lateralis Praeparata.