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排序方式: 共有387条查询结果,搜索用时 31 毫秒
31.
Woo Jung Kim Young Ok Kim Jin Hee Kim Bo-Hye Nam Dong-Gyun Kim Cheul Min An Jun Sik Lee Pan Soo Kim Hye Min Lee Joa-Sup Oh Jong Suk Lee 《Marine drugs》2016,14(1)
The ocean is a rich resource of flora, fauna, and food. A wild-type bacterial strain showing confluent growth on marine agar with antibacterial activity was isolated from marine water, identified using 16S rDNA sequence analysis as Pseudoalteromonas sp., and designated as strain M2. This strain was found to produce various secondary metabolites including quinolone alkaloids. Using high-resolution mass spectrometry (MS) and nuclear magnetic resonance (NMR) analysis, we identified nine secondary metabolites of 4-hydroxy-2-alkylquinoline (pseudane-III, IV, V, VI, VII, VIII, IX, X, and XI). Additionally, this strain produced two novel, closely related compounds, 2-isopentylqunoline-4-one and 2-(2,3-dimetylbutyl)qunoline-4-(1H)-one, which have not been previously reported from marine bacteria. From the metabolites produced by Pseudoalteromonas sp. M2, 2-(2,3-dimethylbutyl)quinolin-4-one, pseudane-VI, and pseudane-VII inhibited melanin synthesis in Melan-A cells by 23.0%, 28.2%, and 42.7%, respectively, wherein pseudane-VII showed the highest inhibition at 8 µg/mL. The results of this study suggest that liquid chromatography (LC)-MS/MS-based metabolite screening effectively improves the efficiency of novel metabolite discovery. Additionally, these compounds are promising candidates for further bioactivity development. 相似文献
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大豆抗营养因子对生长蛋鸡生产性能、氮代谢和小肠内胰蛋白酶活性的影响 总被引:2,自引:0,他引:2
为了观察不同梯度大豆抗营养因子(Antinutritionalfactors、简称ANFs)对不同生理阶段的生长蛋鸡的影响,本试验采用480只海兰褐蛋用雏鸡,以熟豆饼日粮为对照,从3或9周开始给饲3个水平的生大豆日粮(4%,9%和13%),每期每个日粮4个重复。在3~8周和9~18周观察雏鸡的采食量,日增重和饲料效率。在第8和17周分别测定各组的粗蛋白质和干物质的代谢率。并于8、13和18周末每个重复随机抽取试鸡两只屠宰,观察小肠内胰蛋白酶活性的变化。结果表明,3个水平的大豆ANFs对育雏期雏鸡的增重没有影响,育成期对照组的增重明显高于采食生大豆组(P<0.05),大豆ANFs使饲料效率降低,但对氮和干物质的代谢影响不显著;8、13和18周龄雏鸡小肠内胰蛋白酶活性亦无显著变化。 相似文献
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The present study was to evaluate the effects of dried Allium mongolicum Regel (AMR) powder and its water- and fat-soluble extracts (AWE and AFE) on the growth performance, serum metabolites, immune responses, antioxidant status, and meat quality of lambs. A total of 32 male small-tailed Han lambs (5 months old; initial body weight = 34.8 ± 0.40 kg) were used in a 60-d feeding experiment after a 15-d adaptation period. The lambs were randomly divided into 4 groups (n = 8) and fed a basal diet (control, CON group), the basal diet supplemented with dried AMR powder at 10 g/d per lamb (AMR group), the basal diet supplemented with AWE at 3.4 g/d per lamb (AWE group), or the basal diet supplemented with AFE at 2.8 g/d per lamb (AFE group). Blood samples were collected on d 0, 30, and 60 in the feeding experiment (n = 8). At the end of the experiment, the lambs were sacrificed and the longissimus dorsi muscles collected. Growth performance was not significantly affected by dietary supplementation of AMR, AWE and AFE (P > 0.05). However, significantly lower albumin (P = 0.006), total protein (P = 0.006), globin (P = 0.025), and blood urea nitrogen (P = 0.024) concentrations were observed in AFE group relative to CON and AMR groups. Similarly, a significantly lower lactate dehydrogenase activity (P = 0.018) was observed in AFE group relative to AWE group, but not in other groups (P > 0.05). In addition, significantly increasing trends in glutathione peroxidase (P = 0.06) in AMR, AWE, and AFE groups were observed relative to the control group. Furthermore, significantly lower drip loss (P = 0.011) across the treatment groups and cooking loss (P = 0.048) were observed in the AMR group relative to the control group. Taken together, these results indicate that AMR and its extracts had no significant effect on lamb growth performance, antioxidant status, and immune responses, but could significantly improve meat quality without the occurrence of pathological kidney and liver lesions. 相似文献
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采用MaxsignalTM AOZ快速检测试剂盒检测水产品中呋喃唑酮代谢物。通过对精密度、回收率和检测限等项目的测定,验证了方法的可行性。呋喃唑酮代谢物标准液在0.05ng/mL~4.5ng/mL范围内具有良好的线性,微孔板孔间变异系数为3.2%~7.7%。样品批内变异系数为5.2%~8.4%,批间变异系数为6.3%~8.9%,平均回收率为94.5%~98.4%。试剂盒的理论检测下限为0.05μg/Kg。该方法灵敏度高,重复性好,适用于水产品中呋喃唑酮代谢物残留的检测。 相似文献
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木霉菌Td系列菌株代谢产物的室内抑菌谱研究 总被引:1,自引:0,他引:1
利用摇床液体发酵、氯仿萃取木霉菌的代谢产物,采用菌丝生长速度法测定了3个木霉菌菌株的发酵代谢产物对禾谷类镰刀病菌、番茄枯萎病菌、苹果轮纹病菌、立枯丝核菌、苹果炭疽病菌、玉米弯胞病菌和花生网斑病菌的抑菌作用。结果表明,3个木霉菌株代谢产物对7种病原真菌均具有抑制作用,且抑菌作用强度和抑菌谱存在一定的菌株特异性。木霉菌株Td10的代谢产物对禾谷类镰刀病菌和立枯丝核菌抑制作用最强,Td31的代谢产物对苹果轮纹病菌和苹果炭疽病菌抑制作用最强,而Td100的代谢产物对禾谷类镰刀病菌和立枯丝核菌抑制作用较强;3个木霉菌株的代谢产物对花生网斑病菌抑制作用均较弱。 相似文献
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The marine carotenoid fucoxanthin can be found in marine brown seaweeds, the macroalgae, and diatoms, the microalgae, and has remarkable biological properties. Numerous studies have shown that fucoxanthin has considerable potential and promising applications in human health. In this article, we review the current available scientific literature regarding the metabolism, safety, and bioactivities of fucoxanthin, including its antioxidant, anti-inflammatory, anticancer, anti-obese, antidiabetic, antiangiogenic and antimalarial activities, and its protective effects on the liver, blood vessels of the brain, bones, skin, and eyes. Although some studies have shown the bioavailability of fucoxanthin in brown seaweeds to be low in humans, many studies have suggested that a dietary combination of fucoxanthin and edible oil or lipid could increase the absorption rate of fucoxanthin, and thus it might be a promising marine drug. 相似文献
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Zinc (Zn) is an essential micronutrient for plant growth and development, and anthocyanin is a secondary metabolite compound generally produced under stress conditions; both have benefits to human health. Rice is a staple food crop for most of the world’s population, and purple rice is well known as a natural source of Zn and anthocyanins, but their stability depends upon many factors. This review focuses on the opportunity to increase Zn and anthocyanin compounds in purple rice grains via Zn and nitrogen (N) management during cultivation. Variation in grain Zn concentration and anthocyanin compounds is found among purple rice varieties, thus presenting a challenge for breeding programs aiming at high grain Zn and anthocyanin contents. Genetic engineering has successfully achieved a high-efficiency vector system comprising two regulatory genes and six structural anthocyanin-related genes driven by endosperm-specific promoters to engineer purple endosperm rice that can provide new high-anthocyanin varieties. Grain Zn and anthocyanin concentrations in rice can also be affected by environmental factors during cultivation, e.g., light, temperature, soil salinity and nutrient (fertilizer) management. Applying N and Zn fertilizer is found to influence the physiological mechanisms of Zn absorption, uptake, transport and remobilization to promote grain Zn accumulation in rice, while N application can improve anthocyanin synthesis by promoting its biosynthesis pathway via the use of phenylalanine as a precursor. In summary, there is an opportunity to improve both grain Zn and anthocyanin in purple rice by appropriate management of Zn and N fertilizers during cultivation for specific varieties. 相似文献