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排序方式: 共有1279条查询结果,搜索用时 31 毫秒
1.
Pseudorabies virus (PRV) infection leads to severe inflammatory responses and tissue damage, and many natural herbs exhibit protective effects against viral infection by modulating the inflammatory response. An ethyl acetate fraction of flavonoids from Polygonum hydropiper L. (FEA) was prepared through ethanol extraction and ethyl acetate fractional extraction. An inflammatory model was established in RAW264.7 cells with PRV infection to evaluate the anti-inflammatory activity of FEA by measuring cell viability, nitric oxide (NO) production, reactive oxygen species (ROS) release, and mRNA expression of inflammatory factors, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2). Its functional mechanism was investigated by analyzing the phosphorylation and nuclear translocation of key proteins in the nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Our findings indicate that PRV induced inflammatory responses in RAW264.7 cells, and the responses were similar to that in lipopolysaccharide (LPS)-stimulated cells. FEA significantly suppressed NO synthesis and down-regulated both expression and secretion of COX-2, iNOS, and inflammatory cytokines (P<0.05 or P<0.01). FEA also reduced NF-κB p65 translocation into the nucleus and decreased MAPK phosphorylation, indicating that the NF-κB/MAPK signaling pathway may be closely related to the inflammatory response during viral infection. The findings suggested the potential pharmaceutical application of FEA as a natural product that can treat viral infections due to its ability to mitigate inflammatory responses.  相似文献   
2.
This experiment was conducted to evaluate the effect of alfalfa flavonoids (Medicago sativa) on growth performance and serum indexes of sheep.This experiment was performed with hybrid F1 sheep of Suffolk sheep×Small-tailed Han sheep.Twenty-eight sheep with the body weight of (27.02±3.03) kg were randomly divided into 4 groups with 7 replicates in each group and 1 sheep per replicate.Sheep in different groups were fed diets with 0 (group Ⅰ), 0.1% (group Ⅱ), 0.2%(group Ⅲ) and 0.4% (group Ⅳ) alfalfa flavonoids, respectively.The experiment was cosisted of 7-day-preliminary trial and 41-day-formal trial.The results showed as follows:① Dietary supplementation of alfalfa flavonoids had no significant effects on growth performance of sheep(P>0.05).② Dietary supplementation of alfalfa flavonoids had significant effects on the contents of GLB, ASP, BUN, HDL and P in serum (P<0.05).Serum GLB content at the 1st day in group Ⅲ was significantly lower than that in groupsⅠand Ⅱ(P<0.05), serum ASP contents at the 1st and 21th days in group Ⅳ were significantly lower than those in group Ⅰ(P<0.05), serum BUN content at the 1st day in group Ⅳ was significantly lower than that in group Ⅰ(P<0.05), serum HDL content at the 21th day in group Ⅱ was significantly lower than that in groups Ⅰ and Ⅲ (P<0.05), serum P content in group Ⅳ at the 21th day was significantly lower than that in groups Ⅱ and Ⅲ (P<0.05).In conclusion, dietary supplementation of alfalfa flavonoids might modulate lipid metabolism, improve nitrogen utilization, maintain energy metabolic and balance Ca and P contents, and have the potential function for promoting growth and no adverse effect on liver.The results suggested that the appropriate supplemental level of alfalfa flavonoids for sheep was 0.2%.  相似文献   
3.
查尔酮的合成是类黄酮生物合成途径中的一个关键节点。从10个柑橘种质中克隆了查尔酮合成酶(chalcone synthase,CHS)基因,并对其不同时期的果实和叶片中的类黄酮含量进行了测定,分析了CHS基因的序列多态性与类黄酮含量之间的关系;同时通过qRT-PCR检测了CHS基因在不同种质之间以及同一种质的不同组织间的表达差异。结果表明,柑橘CHS基因的核苷酸序列高度保守,相似度达98%以上。聚类分析表明,CHS氨基酸序列的多态性有物种特异性,而且与类黄酮含量有一定的相关性。CHS基因的表达水平在不同种质、部位及生长发育时期有显著差异,这些差异与类黄酮的含量有显著的相关性,说明CHS基因对类黄酮的生物合成有明显影响。  相似文献   
4.
This study was conducted to evaluate the influence of seed priming on drought tolerance of pigmented and non‐pigmented rice. Seeds of pigmented (cv. Heug Jinju Byeo) and non‐pigmented (cv. Anjoong) rice were soaked in water (hydropriming) or solution of CaCl2 (osmopriming). Seeds were sown in soil‐filled pots retained at 70 (well‐watered) and 35% (drought) water‐holding capacity. Drought stress caused erratic and poor stand establishment and decreased the growth of both rice types. More decrease in plant height and leaf area under drought stress was noted in pigmented rice, whereas decrease in root length and seedling dry weight, under drought, was more obvious in non‐pigmented rice. Pigmented rice maintained more tissue water and photosynthesis and had more polyphenols, flavonoids and antioxidant activity than non‐pigmented rice. Seed priming was effective in improving stand establishment, growth, polyphenols, flavonoids and antioxidant activity; however, extent of improvement was more in pigmented rice under drought. In conclusion, drought caused erratic germination and suppressed plant growth in both rice types. However, pigmented rice had better drought tolerance owing to uniform emergence, and better physiological and morphological plasticity. Seed priming was quite helpful in improving the performance of both rice types under drought and well‐watered conditions.  相似文献   
5.
Lettuce is grown in different parts of the world and it is beneficial for health. Light condition is one of the most important environmental factor in regulating growth, development, and phytochemical accumulation in lettuce, particularly when lettuce is produced in a hydroponic system. Due to advances in technologies, artificial light sources have become increasingly capable of providing appropriate quality, intensity, and photoperiod of light in hydroponic lettuce production. This review highlights the progress of current research on the effects of artificial light regulation on growth and phytochemical accumulation in lettuce produced in hydroponic systems.  相似文献   
6.
The impact of mild drought stress (3 weeks at 40 % field water capacity) on yield, physiological processes, accumulation of proline and phenolic compounds and forage quality parameters in forage grasses was evaluated in pot experiments. During four different growing periods, the effects of water deficit were assessed in nine varieties from five species (Lolium perenne, Lolium multiflorum, Festuca pratensis, Festuca arundinacea and Festulolium braunii). All measured parameters were affected by drought stress in the different cuts. Photosynthesis, transpiration rate, stomatal conductance and dry matter yield were significantly lower in drought stress than under well‐watered conditions in all varieties. Higher water‐use efficiency was only observed during the first and fourth drought period, while this was not the case in the second and third. Mild drought stress significantly increased the content of proline, phenolic acid, flavonoids, water‐soluble carbohydrates and protein. All tested grasses showed also an increase of organic matter digestibility and cell wall digestibility under drought stress conditions.  相似文献   
7.
王占斌  赵德明  刘红  毛薇 《中国饲料》2012,(6):22-24,30
以毛泡桐皮为原料,通过乙醇提取,大孔吸附树脂纯化,分别得到毛泡桐皮黄酮的粗提物和纯化物。利用油脂酸败法,测定油脂的过氧化值(POV)和诱导期(IP),计算抗氧化系数(PF)。根据抗氧化系数的大小,确定毛泡桐皮黄酮提取物抗氧化能力的大小。试验结果表明:在相同浓度下,毛泡桐皮黄酮提取物抗氧化能力的大小为:毛泡桐皮黄酮纯化物>粗提物>原粉;并且随着浓度的增加抗氧化能力逐渐增大,其存在着剂量效应关系;0.1%毛泡桐皮黄酮纯化物的抗氧化系数大于2,具有较强的抗氧化能力;0.1%毛泡桐皮黄酮纯化物的抗氧化能力与0.02%BHT的抗氧化能力相当,0.06%毛泡桐皮黄酮纯化物的抗氧化能力与0.05%维生素C的抗氧化能力相当。  相似文献   
8.
李栋 《中国饲料》2021,1(9):34-41
本文采用一种新型绿色溶剂提取红枣总黄酮,并对其提取工艺进行优化。通过单因素试验探究含水量、超声功率、提取时间、提取温度和料液比对红枣总黄酮得率的影响。在此基础上,采用遗传算法优化超声辅助低共熔溶剂提取红枣总黄酮工艺。结果表明:超声辅助低共熔溶剂提取红枣总黄酮最优的工艺参数为:含水量37%、超声功率167 W、提取时间30 min、提取温度54 ℃和料液比1∶26(g/mL)。在此条件下,所得红枣总黄酮得率为(29.33±0.37)mg/g。试验值和理论值的相对误差为1.24%。表明遗传算法可较好地模拟和预测不同提取条件下红枣总黄酮得率,且优化工艺参数是可行的。研究发现低共熔溶剂可作为一种新型、绿色溶剂用于高效提取红枣总黄酮。[关键词] 遗传算法|红枣|总黄酮|低共熔溶剂|工艺  相似文献   
9.
10.
Twelve types of gingko flavonoids were separated with SDS/n -C4 HgOH/n- C7 Hls/H2O microernlusion as developer on polyamide film. The polarity of the microemulsion was regulated through adding or reducing water. Compared with general mobile phase, the sensitivity of detection was improved markedly and the test results were satisfied. By means of HPTLC, fingerprint was argued on gingko flavonoids. It can meet the needs of simple and convenient, reasonable standard quality control methods.  相似文献   
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