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Plant NADPH oxidases are key regulators of plant–microbe interactions and reactive oxygen species (ROS) are essential to plant defences against pathogens. A significant part in the role played by ROS has been ascribed to plant respiratory burst oxidase homologs (RBOHs). In potato (Solanum tuberosum), where RBOHs were previously shown to be involved in wound-induced oxidative burst, we assessed their expression after inoculation with Verticillium dahliae Kleb. and showed that StRbohA was the only homolog to be differentially induced in potato in response to inoculation. In order to investigate the potential role of this gene in plant protection against wilt diseases, we used Agrobacterium-mediated transformation of Arabidopsis to assess the effects of its overexpression on plant responses to V. dahliae. After inoculation with this pathogen, the transformed Arabidopsis line overexpressing StRbohA showed lower disease severity (percent damaged leaf area and vascular discoloration) as compared to the wild type. It also had higher ROS production and more cell death caused by hydrogen peroxide (H2O2), compared to the wild type. Suberization of root cells was also more pronounced in the line overexpressing StRbohA, and supports a possible role for StRBOHA in plant resistance to V. dahliae. Together, these findings indicate that overexpressed StRbohA in Arabidopsis enhances the ROS-mediated defence mechanisms against V. dahliae and can be a potential tool to improve plant resistance to this and other soilborne pathogens that cause wilts in economically important crops. 相似文献
13.
Peru Gopal BISWAS Yuma OHARI Uday Kumar MOHANTA Tadashi ITAGAKI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):666
We analyzed the nuclear ribosomal internal transcribed spacer (ITS) 1 and ITS2 sequences for Bangladesh isolates of Ascaridia galli, and we determined that the sequences were unreliable as molecular markers for distinguishing A. galli from other Ascaridia species, because the sequences showed high identity with that of A. columbae. However, the ITS1 sequences were available for designing PCR primers distinguishable between Ascaridia galli and Heterakis spp. Bangladesh isolates of A. galli constituted a monophyletic clade along with other geographical isolates in the cytochrome c oxidase subunit I (COI) phylogenetic tree, however, we could not clarify the phylogenetic relationships between A. galli and other Ascaridia spp., because their available sequences in GenBank were very few. The developed PCR method using DNA from A. galli and Heterakis spp. eggs would enable differential diagnosis of the individual infections in the future. 相似文献
14.
Yanfen Ma Ying Feng Liwen Song Muyang Li Hongyu Dai Hua Bao Guijie Zhang Lei Zhao Chunhua Zhang Jing Yi Yusheng Liang 《动物营养(英文)》2021,7(1):206
Peripartal cows often experience negative energy balance, and are therefore prone to suffering from metabolic diseases such as hyperketonemia, which causes financial losses in dairy farms. This study aimed to investigate the effect of green tea polyphenol (GTP) supplementation during the periparturient period on production performance, oxidative stress and immunometabolism in dairy cows with hyperketonemia. One hundred Holstein cows were assigned to GTP (0.2 g/kg DM; n = 50) or control (without GTP; n = 50) group based on body weight, previous milk yield, and parity on d 15 before expected parturition. Subsequently, 10 cows with hyperketonemia were selected from each group, according to blood β-hydroxybutyric acid (BHBA) concentration between 1.2 and 2.9 mmol/L from 2 to 3 d postpartum. All cows were fed a close-up diet and a lactation diet with or without GTP supply from 15 d prepartum until 30 d postpartum. Milk and blood samples were obtained from 20 cows selected with hyperketonemia on 10, 20, and 30 d postpartum. Compared with control cows, greater milk yield and lower somatic cell count were observed in GTP cows. The GTP group had lower concentrations of BHBA, free fatty acids, cholesterol, triglyceride, reactive oxygen species, malondialdehyde, and hydrogen peroxide, greater concentrations of glucose, lower activities of aspartate aminotransferase, alanine aminotransferase, and glutamyl transpeptidase, alongside greater activities of superoxide dismutase, glutathione peroxidase, and total antioxidant capacity. Additionally, GTP supplementation up-regulated concentrations of interleukin-6 and interleukin-10, but down-regulated concentrations of tumor necrosis factor-α, interleukin-1β, interleukin-2, interleukin-8, and interferon-γ in plasma. Greater concentrations of plasma immunoglobulin G were also detected in the GTP group. Overall, the data suggested that GTP supplementation from 15 d prepartum to 30 d postpartum improved the milk yield and health status in cows with hyperketonemia during early lactation. 相似文献
15.
为研究冷冻贮藏中不同部位酚类物质和多酚氧化酶的分布特征,以青海省地方梨优良品种‘软儿梨’果实为研究材料,采用高效液相色谱法和比色法测定软儿梨果实后熟(室温)、冻藏(-18℃)和解冻(室温)3个时期的果皮、果肉中总多酚、绿原酸的含量和多酚氧化酶活性。结果表明:软儿梨果实后熟后,酚类物质果肉?果皮,多酚氧化酶则果皮?果肉;冷冻贮藏过程中,不同部位的酚类物质和多酚氧化酶均呈现不同程度的升高,但绿原酸在果皮急剧下降、果肉中略有增加。解冻后总体呈下降趋势,2个部位总酚、多酚氧化酶下降明显,而果皮中的绿原酸变化不大。研究表明:软儿梨果实后熟后,酚类物质和多酚氧化酶分布呈现区域化,冷冻贮藏加剧了酚类物质和多酚氧化酶活性的积累,导致了软儿梨冷冻贮藏后果皮先于果肉发生了褐变。 相似文献
16.
17.
桉树连作对土壤多酚氧化酶活性及酚类物质含量的影响 总被引:3,自引:0,他引:3
研究不同连栽代次巨尾桉人工林(第一代为2年生和5年生,第二代为2年生)土壤多酚氧化酶活性和酚类物质含量的变化规律,并分析两者空间分布以及相关性。结果表明:(1)林间土壤多酚氧化酶活性高于根区,并随着连栽年限增加呈上升趋势。(2)总酚、复合性酚含量根区土壤高于林间土,并随着连栽年限增加而降低,证明桉树连栽短期内没有造成酚类物质的积累;水溶性酚含量林间土高于根区土,随连栽年限增加而增加,但其含量较低,未达到毒害程度;在无土壤酚类物质来源情况下,水溶性酚和复合态酚均发生消解,含量下降。(3)土壤多酚氧化酶活性与总酚、复合性酚呈显著负相关,跟水溶性酚呈极显著正相关,肯定了多酚氧化酶对酚类物质的降解作用。多酚酶活性和酚类物质皆与土壤pH值有较显著的相关性,两者受土壤pH值影响较大。 相似文献
18.
蚯蚓与黑麦草相互作用对土壤中荧蒽去除的影响 总被引:1,自引:0,他引:1
Earthworms can promote the bioremediation of contaminated soils through enhancing plant growth and microorganism development. The individual and combined effects of earthworms and ryegrass (Lolium multiflorum Lam.) on the removal of fluoranthene from a sandy-loam alluvial soil were investigated in a 70-d microcosm experiment. The experiment was set up in a complete factorial design with treatments in four replicates: without earthworms or ryegrass (control, CK), with earthworms only (E), with ryegrass only (P), and with both earthworms and ryegrass (EP). The residual fluoranthene, microbial biomass C, and polyphenol oxidase activity in the soil changed significantly (P<0.01) with time. In general, the residual concentration of fluoranthene in the soil decreased sharply from 71.8-88.7 to 31.7-37.4 mg kg 1 in 14 d, and then decreased gradually to 19.7-30.5 mg kg 1 on the 70th d. The fluoranthene concentration left in the soil was the least with both earthworms and ryegrass, compared to the other treatments at the end of the experiment. Half-life times of fluoranthene in the E, P, and EP treatments were 17.8%-36.3% smaller than that of CK. More fluoranthene was absorbed by earthworms than ryegrass. However, the total amounts of fluoranthene accumulated in both the ryegrass and earthworms were small, only accounting for 0.01%-1.20% of the lost fluoranthene. Therefore, we assumed that microbial degradation would play a dominant functional role in fluoranthene removal from soil. We found that earthworms significantly increased microbial biomass C and polyphenol oxidase activity (P<0.01) in the presence of ryegrass at the end of the experiment. Furthermore, microbial biomass C and polyphenol oxidase activity were significantly (P<0.05) and negatively related to the residual fluoranthene concentration. This implied that earthworms might promote the removal of fluoranthene from soil via stimulating microbial biomass C and polyphenol oxidase activity. 相似文献
19.
红松种子壳多酚物质的提取及抗氧化特性 总被引:5,自引:0,他引:5
该文选取超声波辅助提取法,采用单因素试验及响应面设计,研究了超声波提取时间、温度、乙醇浓度及料液比对红松种子壳中多酚类化合物提取的影响。并利用Fenton体系、1,1-二苯基-2-苦苯肼(DPPH·)体系及邻苯三酚体系测定其提取成分的抗氧化活性。结果表明,松壳中多酚成分提取的最佳工艺条件为:超声提取时间2.80h、料液比1∶26.36(g/mL)、乙醇浓度42.86%、提取温度80℃,多酚得率7.96mg/g。在此优化条件下,红松种子壳提取物对羟自由基(甲基紫法)、DPPH·自由基及超氧阴离子均具有较强清除作用,半数抑制浓度分别为6.67×10-4、2.34×10-2、3.97mg/mL。 相似文献
20.
通过单因素及多因素试验,探讨抑制荸荠中多酚氧化酶活性的效果。L_9(3~3)正交试验结果表明:柠檬酸预煮液的质量分数0.5%,预煮温度100℃,预煮时间5 min为最优预煮条件。 相似文献