[Domesticated cultivation and genetic breeding of Chenopodium quinoa].

Quinoa (Chenopodium quinoa Willd, 2n=36) is an annual crop belonging to the genus Chenopodium in Amaranthaceae, and originated from the Titicaca lake of the Andes region in the South America. Due to its high nutritional values and adapted tolerance to various abiotic stresses, quinoa was considered a crop with high application potential, but improvement is still needed for the development and utilization of crop. Therefore it attains the attention of biological scientists and breeders. In recent years, with the pursuit of better health and higher quality of life, the consuming of quinoa grains has increased dramatically. Cultivation and breeding of quinoa has received more attention to ensure global food security as well. On the basis of our multiple years of experience in quinoa germplasm collection which were evolution from Andes region, the focus of this review is on the nutritional quality and application of quinoa, species origination and evolution, domestication by human, and genetic breeding progress and trends, so that a better understanding of quinoa values can be achieved. We aim to help increase farmers' income in poverty areas and ensure national food security by promoting development of quinoa industry in China.

Two new phenolic compounds and antitumor activities of asparinin A from Asparagus officinalis.

Two new phenolic acid compounds, asparoffin C (1) and asparoffin D (2), together with four known compounds, asparenyol (3), gobicusin B (4), 1-methoxy-2-hydroxy-4-[5-(4-hydroxyphenoxy)-3-penten-1-ynyl] phenol (5), and asparinin A (6), have been isolated from the stems of Asparagus officinalis. The structures were established by extensive spectroscopic methods (MS and 1D and 2D NMR). Compound 6 has obvious antitumor activities both in vitro and in vivo.

Two new acetylenic compounds from Asparagus officinalis.

Two new acetylenic compounds, asparoffins A (1) and B (2), together with two known compounds, nyasol (3) and 3″-methoxynyasol (4), were isolated from stems of Asparagus officinalis. The structures of two new compounds were elucidated on the basis of detailed spectroscopic analyses (UV, IR, MS, 1D, and 2D NMR). All compounds were evaluated for their cytotoxicities against three human cancer cell lines.

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.

Enhancement of Biocontrol Activities and Cyclic Lipopeptides Production by Chemical Mutagenesis of Bacillus subtilis XF-1, a Biocontrol Agent of Plasmodiophora brassicae and Fusarium solani.

Bacillus subtilis XF-1 has been used as a biocontrol agent of clubroot disease of crucifers infected by Plasmodiophora brassicae, an obligate pathogen. In order to maximize the growth inhibition of the pathogen, random mutagenesis using N-methyl-N'-nitro-N-nitrosoguanidine was applied to strain XF-1. The efficacy of 226 selected mutants was assessed against the growth of an indicator fungal pathogen: Fusarium solani using agar plate assay and the disruptive effects on the resting spores of P. brassicae. Four mutants exhibited inhibition activity significantly higher than the wild type. The cell extracts of these mutants and the XF-1 were subjected to matrix-assisted laser desorption ionization-time of flight mass spectra analysis, and three families of cyclic lipopeptides (CLPs) fengycin, surfactin and iturin were identified from the parental strain and the screened mutants. However, the relative contents and compound diversity changed after mutagenesis, and there was slight variation in the surfactin and fengycin. Notably, only 5 iturin components were discovered from the wild strain XF-1, but 13 were obtained from the mutant strains, and the relative CLPs contents of all mutant strains increased substantially. The results suggested that CLPs might be one of main biocontrol mechanisms of the clubroot disease by XF-1. The 4 mutants are far more effective than the parental strain, and they would be promising biocontrol candidates not only against P. brassicae but probably other plant diseases caused by fungi.

Diversity and active mechanism of fengycin-type cyclopeptides from Bacillus subtilis XF-1 against Plasmodiophora brassicae.

Bacillus subtilis XF-1, a strain with demonstrated ability to control clubroot disease caused by Plasmodiophora brassicae, was studied to elucidate its mechanism of antifungal activity against P. brassicae. Fengycin-type cyclopeptides (FTCPs), a well-known class of compounds with strong fungitoxic activity, were purified by acid precipitation, methanol extraction, and chromatographic separation. Eight homologs of fengycin, seven homologs of dehydroxyfengycin, and six unknown FTCPs were characterized with LC/ESI-MS, LC/ESI-MS/MS, and NMR. FTCPs (250 microg/ml) were used to treat the resting spores of P. brassicae (10(7)/ml) by detecting leakage of the cytoplasm components and cell destruction. After 12 h treatment, the absorbencies at 260 nm (A(260)) and at 280 nm (A(280)) increased gradually to approaching the maximum of absorbance, accompanying the collapse of P. brassicae resting spores, and nearly no complete cells were observed at 24 h treatment. The results suggested that the cells could be cleaved by the FTCPs of B. subtilis XF-1, and the diversity of FTCPs was mainly attributed to a mechanism of clubroot disease biocontrol.

ESI LC-MS and MS/MS characterization of antifungal cyclic lipopeptides produced by Bacillus subtilis XF-1.

Bacillus subtilis XF-1 (CGMCC No. 2357), a patent strain with good effects for controlling the clubroot of crucifer and many pathogenic fungi, was predicted to produce cyclic lipopeptide (CLP) antibiotics based on its genomic analysis. In this study, the CLPs were purified and determined with the following protocol: the supernatant of XF-1 cultivating mixture was firstly precipitated, then the precipitants were extracted with methanol and further separated by Sephadex LH-20 chromatography to test its antifungal activities. Fungi-inhibiting fractions were further characterized with LC/ESI-MS and LC/ESI-MS/MS. The results show that four molecular ion peaks [M+H]⁺ (m/z 1,464, 1,478, 1,492 and 1,506) from fungi suppression fraction were identified as fengycin A with fatty acid of C16-C19, fengycin B (C14-C17), fengycin C (C15-C18), fengycin D (C15-C18) and fengycin S (C15-C18). Fengycin C (C15 and C18), fengycin D (C15, C16 and C18) and fengycin S (C15, C16 and C18) were reported for the first time. The diversity of the fengycins that exist in this strain will help the elucidation of their biocontrol mechanisms.