Atroposelective N-N Axes Synthesis via Electrochemical Cobalt Catalysis.

Here, we disclosed an unprecedented cobalt electrocatalyzed atroposelective C-H activation and annulation for the efficient construction of diversely functionalized N-N axes in an undivided cell. A broad range of allene substrates and benzamides bearing different functionalities are compatible with generating axially chiral products with good yields and excellent enantioselectivities (up to 92% yield and 99% ee). A series of synthetic applications and control experiments were also performed, which further expanded the practicality of this strategy.

Metabolomics and transcriptomics provide insights into the flavonoid biosynthesis pathway in the roots of developing Aster tataricus.

Aster tataricus (L.) is an important medicinal plant in China. Its roots are rich in flavonoids, the main medicinal components. However, the molecular basis of flavonoid biosynthesis in the roots of A. tataricus remains unclear. In this study, the content of total flavonoid of A. tataricus roots at different developmental stages was measured first, and the results showed that the content of total flavonoid gradually decreased from September to November, which may be caused by the stagnation of A. tataricus growth due to the decrease in temperature after September. Then, an integrated analysis of transcriptome and metabolome was conducted on five developing stages of A. tataricus roots to identify flavonoid compositions and potential genes involved in flavonoid biosynthesis. A total of 80 flavonoid metabolites, of which 75% were flavonols and flavonoids, were identified in metabolomic analyses, among which isorhamnetin, kaempferol, quercetin, and myricetin were the main skeletons of these flavonoids. Cluster analysis divided these 80 flavonoids into 3 clusters. The compounds in cluster I mainly accumulated in S1, S3, and S5. In cluster II, the relative content of the flavonoid metabolites showed an upward trend from S2 to S4. In cluster III, the flavonoids decreased from S1 to S5. A total of 129 structural genes, including 43 PAL, 23 4CL, 9 C4H, 4 CHS, 18 CHI, 3 F3H, 5 F3'H, 1 F3'5'H, 21 FLS, and 2 FSII, and 65 transcription factors, including 22 AP2/ERF, 7 bHLH, 5 bZIP, 8 MYB, 11 NAC, and 12 WRKY, showed significant correlation with total flavonoid content. Eighteen genes (7 4CL, 5 C4H, 2 CHI, 1 F3H, and 3 FLS) and 30 genes (5 PAL, 9 4CL, 1 C4H, 2 CHI, 1 F3H, 1 DFR, 7 3AT, 1 BZ1, and 3 UGT79B1) were identified as key structural genes for kaempferol and anthocyanins biosynthesis, respectively. Our study provides valuable information for understanding the mechanism of flavonoid biosynthesis in A. tataricus root.

Polysaccharides from Polyporus umbellatus: A review on their extraction, modification, structure, and bioactivities.

Polyporus umbellatus (Pers.) Fries, a well-known medicinal fungus, has been reported to exhibit important functions of diuresis and dampness infiltration in traditional Chinese Medicine. Accumulating evidences have demonstrated that the P. umbellatus polysaccharides (PUPs) are the main and representative pharmacologically active ingredients and display multiple bioactivities both in vivo and in vitro methods, such as those of antioxidant, immunomodulatory, antitumor, anti-proliferative and hepatoprotective. Besides, many PUPs have been isolated from the different sources of P. umbellatus, including sclerotia, fruiting body, mycelia and fermentation liquid of this fungus. The purpose of the present review is to comprehensively and systematically reorganize the available information related to the extraction, purification, modification, structure characterization and to discuss diverse biological activities of PUPs to support their potential application value in pharmaceuticals field, functional foods and cosmetics areas. In addition, new invaluable insights on the future research with PUPs have also been proposed in the important areas of structural characterization and pharmacological activities.

[Influence of different processing methods and mature stages on 3,29-dibenzoyl rarounitriol of Trichosanthes kirilowii seeds].

OBJECTIVE: To study the different mature stages and the best processing methods on the quality of Trichosanthes kirilowii seeds. METHODS: The content of 3,29-dibenzoyl rarounitriol in Trichosanthes kirilowii seeds was determined by HPLC. The sample of different mature stages such as immature, near mature and fully mature and processed by different methods were studied. RESULTS: Fully mature Trichosanthes kirilowii seeds were better than the immatured, and the best processing method was dried under 60degrees C, the content of 3,29-dibenzoyl rarounitriol reached up to 131.63microlg/mL. CONCLUSION: Different processing methods and different mature stages had a significant influence on the quality of Trichosanthes kirilowii seeds.

[Study on secondary metabolic organ of echinacoside in herbs of Cistanche tubulosa].

OBJECTIVE: It could give some theory support of confirming the secondary metabolism organ and regulation of echinacoside in Cistanche tubulosa by searching parasitic growth of C. tubulosa ahd echinacoside variation in different organs of host and parasite. METHOD: The echinacoside content was analyzed by HPLC. The relationship between dry matter accumulation and echinacoside accumulation of C. tubulosa as the well as root diameter of host were comparatively analyzed. RESULT: With the increase of dry matter accumulation of C. tubulosa, echinacoside accumulation increased significantly, and both of them were in significantly positive correlated with the root diameter of host. Echinacoside content in haustorium phloem was 15.53%, higher than that of haustorium xylem, C. tubulosa plant and other organs. CONCLUSION: Haustorium phloem was probably the secondary metabolism organ of echinacoside in C. tubulosa.

[Inoculation experiments of Cistanche tubulosa on 8 introduced Tamarix species].

OBJECTIVE: To analyze the inoculation ratio and echinacoside content of Cistanche tubulosa and provide theoretical basis for Tamarix introduction, resource protection and screening of C. tubulosa. METHOD: 8 Tamarix species were introduced in the North China Plain and inoculation of C. tubulosa was conducted on all species. Phenylethanoid glycosides fingerprinting and echinacoside content of C. tubulosa were analyzed by using HPLC. RESULT: The adaptability of 8 Tamarix species were significantly different, phenylethanoid glycosides component of C. tubulosa on T. gansuensis and T. austromongolica were basically identical in contrast to T. chinensis, echinacoside content showed no obvious difference in C. tubulosa plant growing 4 months. CONCLUSION: T. gansuensis and T. Austromongolica are suitable for the host introduction plant of C. tubulosa resource protection and screening in North China Plain.

[Studied of dry matter accumulation and echinacoside content of Cistanche tubulosa in Huabei plain].

OBJECTIVE: To give some theory support of Cistanche tubulosa cultivation by searching dry matter accumulation and echinacoside content of C. tubulosa. METHOD: Dry matter accumulation content of C. tubulosa culturing in Huabei plain was analysed in different growth season of C. tubulosa. Echinacoside content was determined by HPLC. RESULT: Dry matter accumulation of C. tubulosa showed "S" variation. Dry matter accumulation increased fastest in September among growing seasons. Dry matter amount was 138.58 g after C. tubulosa grew a year. Dry matter amount decreased significantly along with inoculation time retarded. Echinacoside content was 30.59% when C. tubulosa grew in 5 months, decreased guadully after that, and 9.76% in annual. CONCLUSION: Variation rule of dry matter accumulation and echinacoside content was found in C. tubulosa that grew one year in Huabei plain.

[Effects of cultivation technique on yield and favonoid content of Chrysanthemum flower (Qiju) grown in Hebei].

OBJECTIVE: To study the effect of cultivation techniques on the flower yield flavonoid content in Chrysanthemum flower grown in Hebei. METHOD: Studied on flowers yield and three factors (transplanting date and plant density and fertilizer quantity) were examined in field experiment at 4 treatments levels. RESULT AND CONCLUSION: The best results were obtained at following conditions: diammonium phosphate 300 kg x hm(-2) and potassium sulfate 150 kg x hm(-2) fertilized before transplanting, transplanting at the first ten days of May and the spacing 40 cm x 40 cm.

[Study on inoculation technology of Cistanche tubulosa in the field].

OBJECTIVE: To increase inoculation rate of Cistanche tubulosa in the field by studying inoculation technologies. METHOD: Root-tube inoculation methed was used on field experiments. Inoculation rate of C. tubulosa was compared to different size seeds and inoculation mediums and inoculation time. RESULT AND CONCLUSION: May is suitable inoculation time. The inoculation rate of C. tubulosa is 92.5% while the seed width is more than 0.7 mm and coarse sand is selected during inoculation period.

[Morphology of seed germination and parasitism in Cistanche tubulosa].

OBJECTIVE: To understand the process of Cistanche tubulosa. METHOD: The process of seed germination and parasitism was observed using stereomicroscope. RESULT: Seedling of C. tubulosa sprouted after forty day without host root's contact in fields, a tube-like-organ formed and grew auger-type from host root, the tuber apex where touches host root swelled and formed haustorium. Haustorium intruded host root epidermis and vascular bundles, and released brown substances. Then, embryo bud with six or more young leaves formed, finally the swelled tuber-like-organ broken and seed coat shed. Due to the parasitism of C. tubulosa, the host root near stem site swelled, but the other part, shrunk and disappered gradually. CONCLUSION: Seed of C. tubulosa could germinate indepently in fields. Tuber-like-organ formatin, haustorium formation and bud formation are key steps of C. tubulosa seedling development.