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991.
Duan Yafei Zhang Jiasong Huang Jianhua Jiang Shigui 《Probiotics and antimicrobial proteins》2019,11(3):938-945
Probiotics and Antimicrobial Proteins - The present study investigated the effects of the dietary probiotic Clostridium butyricum (CB) on the growth, intestine digestive enzyme activity,... 相似文献
992.
993.
[目的] 明确佛冈县不同类型橘园柑橘木虱的种群动态,为当地柑橘木虱及柑橘黄龙病的防治工作提供科学依据。[方法] 通过2015-2016年的系统调查,对广东省佛冈县砂糖橘园的柑橘木虱种群消长动态进行研究,对比分析了不同处理措施对柑橘木虱种群数量的影响。[结果] 1-3月柑橘木虱发生危害较轻,随着嫩梢增多,其种群数量开始上升,6-9月为种群发生高峰期,期间出现多个发生高峰,10月之后种群数量逐渐进入消退期,种群数量维持在较低水平;2015、2016年佛冈县柑橘木虱的季节性消长动态基本一致,但种群发生量存在明显差别;3种不同类型橘园内柑橘木虱种群发生数量也存在显著差异,常年失管橘园柑橘木虱种群发生数量最高,常规水肥管理橘园次之,二者均显著高于常规水肥管理及化学防治橘园。[结论] 化学防治可在一定程度上控制柑橘木虱的种群数量,及时清理失管橘园对控制柑橘木虱和柑橘黄龙病传播至关重要。 相似文献
994.
995.
Ilyonectria mors-panacis, previously Cylindrocarpon destructans, is the main plant pathogen responsible for the fungal disease ginseng root rot. This economically important disease, also called disappearing root rot, reduces crop yields by an average of 30% at harvest. While the disease is well studied from ecological and genomic perspectives, the role of I. mors-panacis secondary metabolites in the disease process is not well understood. Our previous metabolomics study showed Ilyonectria strains that cause ginseng root rot produce mixtures of putative resorcylic acid lactones, whereas avirulent strains did not, and collectively synthesize fewer metabolites. To confirm these metabolomics findings, we isolated and characterized the secondary metabolites from I. mors-panacis DAOMC 251601, a strain that causes ginseng root rot. From its EtOAc soluble culture filtrate extract, eight resorcylic acid lactones (1-8), including chlorinated and non-chlorinated congeners, were characterized by HRMS and spectroscopic approaches (NMR, OR, UV). The structure of one new metabolite, named radicicol E (1), was elucidated and additional spectroscopic data for the known compound nordinonediol (2) are reported. Further, radicicol (9) production was confirmed by comparison to a standard. The roles that resorcylic acid lactones and the siderophore N,N′,N” triacetylfusarine C have in promoting Ilyonectria ginseng root rot are also discussed. 相似文献
996.
Three new cassane-type diterpenoids, namely caesalatic acids A–C (1 ‒3), and seven known compounds, resveratrol (4), piceatannol (5), aromadendrin (6), taxifolin (7), 3,4-dihydroxybenzaldehyde (8), methyl gallate (9), and loliolide (10) were isolated from the methanol extract of the Caesalpinia latisiliqua (Cav.) Hattink leaves. Their chemical structures were elucidated by 1D- and 2D-NMR, MS data, circular dichroism, and compared with NMR data in the literature. 相似文献
997.
Two new cyclopeptides simplicilliumtides N and O (1 and 2) along with three known analogues verlamelins A, B and simplicilliumtide J (3-5) were isolated from the deep-sea-derived fungal strain Simplicillium obclavatum EIODSF 020 by bioassay-guided isolation method. Their structures of 1 and 2 were elucidated by spectroscopic analysis, and their amino acid configurations were determined by Marfey’s method. All isolated compounds showed significant antifungal activity against two phytopathogenic fungi Alternaria solani and Colletotricum asianum with MIC values of 0.195–6.250 μg/disc. This study suggests the fungal strain S. obclavatum EIODSF 020 is a new source for developing natural fungicides. 相似文献
998.
Phytochemical investigation of the leaves and twigs of Tabernaemontana bovina led to the isolation of 10 monoterpenoid indole alkaloids, including two new taberbovinines A (1) and B (2) along with eight known analogs: mehranine (3), 14α,15β-dihydroxy-N-methylaspidospermidine (4), (16S*)− 15-epi-E-isositsirikine (5), (16R*)− 15-epi-E-isositsirikine (6), 16 R*-19,20-E-isositsirikine acetate (7), hecubine (8), voafinidine (9), and voacangarine (10). Taberbovinine B (2) represents the first case of an unusual ring C/D cleavage among the natural Corynanthe-type alkaloids. Compounds 2 and 8 exhibited weak cytotoxicity against five human cancer cell lines, including SK-LU-1, HepG2, MCF-7, SK-Mel-2, and LNCaP, with IC50 values ranging from 42.9 to 66.3 μM, whereas compounds 4 − 6 and 9 were cytotoxic toward MCF-7, SK-LU-1 and LNCaP cells, with IC50 values in a range of 51.6–93.3 μM. 相似文献
999.
Two new stilbeno-phenylpropanoid compounds, given the trivial names chamaecristanols A and B (1 and 2), were isolated from the ethyl acetate-soluble partitions of separate methanol extracts of the aerial parts of Chamaecrista pumila (Lam.) K. Larsen. The structures of these compounds were determined on the basis of interpretation of their spectroscopic data and comparison with reported literature data. Their inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 cells were evaluated. Results showed that compounds 1 and 2 significantly inhibited NO production with IC50 values of 41.69 ± 1.34 and 32.14 ± 0.15 µM, respectively. 相似文献
1000.
One new chalcone glycoside, chalcononaringenin 2′,4-di-O-β-glucopyranoside (1), one new alkaloid, asageoside (2), and sixteen known flavonoids and aurone glycosides, (3-18) were isolated from a methanol extract of the aerial parts of Asarum geophilum Hemsl. Their structures were elucidated by spectroscopic methods, including 1D- and 2D NMR experiments as well as MS analysis and comparison of their NMR data with those reported in the literature. In addition, the hepatoprotective effects of all compounds were also evaluated in HepG2 cells at concentrations of 100, 20.0, 4.0, and 0.8 μg/mL. Quercetin, an antioxidant that showed hepatoprotective effect, was used as the positive control. Compounds 11 and 16 showed significant hepatocellular protective activity with IC50 values of 13.4 ± 1.2 and 73.6 ± 9.1 μg/mL, respectively. 相似文献