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141.
Two plum (Prunus salicina Lindl.) cultivars ‘Black Splendor’ (BS) and ‘Royal Rosa’ (RR) were treated with methyl jasmonate (MeJA) at 3 concentrations (0.5, 1.0 and 2.0 mM) along the on-tree fruit development: 63, 77 and 98 days after full blossom (DAFB). On a weekly basis, fruit samples were taken for measuring fruit size and weight and parameters related to quality. Results revealed that MeJA was effective in increasing fruit size and weight, the 0.5 mM being the most effective for BS cultivar and 2.0 mM for RR. At harvest, those fruit treated with 0.5 mM MeJA had the highest firmness and colour Hue values. Total acidity was also generally higher in MeJA-treated fruit than in controls, while the content of total soluble solids remained unaffected. In addition, total phenolics and total antioxidant activity were found at higher concentrations in 0.5 and 2.0 mM MeJA-treated than in control fruit over at last 3 weeks of fruit development for BS and RR cultivars, respectively. Overall results suggest that MeJA could be a promising preharvest tool to increase plum size and quality with enhanced bioactive compounds and antioxidant activity, although the optimum concentration is cultivar dependent. 相似文献
142.
Selenium and vitamin E increases polymorphonuclear cell phagocytosis and antioxidant levels during acute mastitis in riverine buffaloes 总被引:1,自引:0,他引:1
Reena Mukherjee 《Veterinary research communications》2008,32(4):305-313
Antioxidant, antiinflammatory and phagocytic activities were studied in milk polymorphonuclear cells (PMNs) isolated from
healthy buffaloes (group I) and during clinical mastitis with the treatment of Enrofloxacin alone (group II) and combined
treatment with Enrofloxacin and Vitamin E plus selenium (group III). On days 0,3, 8 and 15 the milk Somatic cell count (SCC)
were significantly higher in mastitic milk than in milk obtained from healthy buffaloes. In group II SCC decreased significantly
on day 3 and day 8, however in group III reduction in SCC was observed on day 3, day 8 and day 15 (P < 0.05). The antiinflammatory activity was evaluated by determining nitrite plus nitrate (NOx) production in the milk PMNs
before treatment and on day 8. NOx activity was significantly higher in mastitic milk than from healthy controls, both before
and after treatment (P < 0.05). In group II and group III the activity decreased significantly on day 8 (P < 0.05). The Glutathione peroxidase (GSH-Px) activity was estimated in the milk polymorphonuclear cell (PMNs) supernatant.
GSH-Px activity was significantly lower in mastitic buffaloes than in healthy controls, both before and after treatment (P < 0.05). In group II levels did not change in response to treatment, whereas in group III levels had increased significantly
on day 8 (P < 0.05). The phagocytic activity (PA) (percentage of neutrophil that had phagocytosed 1–6 bacteria) and phagocytic index
(PI) (average number of bacteria/ leukocytes counted in 100 cells) of the milk PMNs was significantly lower in mastitic buffaloes
(P < 0.05). In group II the PA and PI did not change in response to treatment, whereas in group III both the parameters had
increased significantly on day 8 (P < 0.05). The results of the present experiment indicated enhancement of antioxidative and cellular defense and reduction
of somatic cell count in the mastitic animals treated with Enrofloxacin and Vitamin E plus Selenium as compared to the Enrofloxacin
treatment alone. Hence Vitamin E plus selenium therapy may be added along with the antibiotics for effective amelioration
of intramammary infection in buffaloes. 相似文献
143.
《动物营养(英文)》2019,5(3):227-233
The effects of dietary zinc and L-arginine supplements on the weight gain, feed efficiency, antioxidant capacity and oxidative status of weanling piglets raised under commercial conditions were examined. A total of 288 piglets aged 21 d were fed for 15 d a diet supplemented or not with 2,500 mg/kg of zinc (provided as zinc oxide) and 1% L-arginine·HCl. The 4 treatments were distributed in a randomized complete block design with 6 initial body weight categories (12 animals per pen). Access to feed and water was ad libitum. Data were analyzed as a 2 × 2 factorial experiment using the SAS MIXED procedure, with zinc and arginine as the main independent variables. Blood collection day (d 8 and 15, samples were collected from the same 2 piglets in each pen before the morning feeding) was included as a third factor. The zinc supplement increased the average daily gain (ADG) from d 0 to 7, d 8 to 15 and d 0 to 15 (0.289 vs. 0.217 kg/d), average daily feed intake (ADFI) from d 8 to 15 and d 0 to 15 (0.338 vs. 0.279 kg/d) and the gain to feed (G:F) ratio from d 0 to 7 and d 0 to 15 (0.86 vs. 0.77) (P < 0.001). Both supplements significantly decreased the malondialdehyde concentration (zinc: 4.37 vs. 3.91 μmol/L, P = 0.005; arginine: 4.38 vs. 3.89 μmol/L, P = 0.002). Total antioxidant capacity and reduced glutathione (GSH) increased from d 8 to 15 (0.953 vs. 1.391 μmol/L, 2.22 vs. 3.37 μmol/L, P < 0.05) regardless of dietary treatment. Total and oxidized GSH concentrations on d 8 were higher in response to the combined supplements (zinc × arginine interaction, P < 0.05). Piglets fed either Zn-supplemented diet had a lower haptoglobin serum concentration (509 vs. 1,417 mg/L; P < 0.001). In conclusion, the zinc supplement improved piglet growth performance (ADG and ADFI) and oxidative status (based on malondialdehyde concentration). The arginine supplement had a limited effect on growth performance and oxidative status under these conditions. 相似文献
144.
The oxidant/antioxidant equilibrium in horses 总被引:1,自引:1,他引:0
Kirschvink N de Moffarts B Lekeux P 《Veterinary journal (London, England : 1997)》2008,177(2):178-191
Since "free radical research" started in 1954, understanding the role of oxidants and antioxidants in physiological and pathological conditions has increased continuously. Oxidants are essentially generated by metabolic enzymes, inflammatory cells and mitochondrial electron leakage; they are indispensable for the cellular redox regulation and may, under certain conditions, have a pro-inflammatory stimulatory role. Endogenous and exogenous antioxidants counterbalance the oxidative processes and so maintain the oxidant/antioxidant equilibrium. Excessive oxidant generation or antioxidant insufficiency can lead to oxidative stress. The aims of this review are: (1) to provide an insight into the concept of the oxidant/antioxidant equilibrium by briefly introducing the oxidant and the antioxidant systems; (2) to describe how the oxidant/antioxidant equilibrium or oxidative stress can be evaluated in horses, and (3) to summarise current knowledge about oxidative stress in equine medicine and equine exercise physiology. 相似文献
145.
146.
目的:对大枣叶水提醇沉物的抗氧化活性进行研究,筛选抗氧化活性良好的醇沉方式和醇沉浓度。方法:分别用不同浓度的乙醇直接醇沉、分级醇沉得到大枣叶醇沉物,以ABTS自由基清除率、DPPH自由基清除率、羟基自由基清除率、还原力为考察指标,筛选抗氧化活性高的醇沉工艺。结果:大枣叶分级醇沉物总体上抗氧化活性强于直接醇沉,大枣叶水提物直接醇沉使含醇量达80%的醇沉物抗氧化活性较佳,分级醇沉物在4种不同抗氧化考察方法下呈现不同规律。结论:优选的醇沉方式和醇沉浓度,可为大枣叶健康产品的开发提供依据。 相似文献
147.
遮荫处理及恢复光照对白菜生长及活性氧代谢的影响 总被引:2,自引:0,他引:2
以白菜耐弱光品种‘矮王’和不耐弱光品种‘绿优’为材料,研究遮荫处理及恢复光照过程中植株生长、活性氧代谢和抗氧化酶活性的变化。结果表明,遮荫处理后‘矮王’品种生长减缓, ‘绿优’品种生长停滞;2品种的MDA含量、O2-. 产生速率和H2O2含量呈现先下降后上升的趋势, POD活性呈上升趋势,而SOD、CAT、APX等酶活呈先下降后上升的趋势;恢复生长光照后,2品种的 MDA含量、O2-. 产生速率和H2O2含量均迅速上升,几种酶活也呈加速上升趋势。遮荫处理后期与恢复光照后‘绿优’的膜脂过氧化现象较‘矮王’严重,‘矮王’通过增加抗氧化酶活性,有效地减轻了膜脂过氧化程度。 相似文献
148.
盐胁迫对番茄幼苗生长及保护酶活性的影响 总被引:5,自引:1,他引:4
测定了0、100、200、300.mmol/L NaCl浓度处理下番茄幼苗地上及地下部分的干鲜重;叶绿素含量、光合特性;SOD、POD、CAT、APX活性及O2·-产生速率.结果表明:随NaCl处理浓度的增加,番茄幼苗的FW、DW、Pn、GS呈现降低趋势;Ci、chl、SOD、POD、CAT、APX活性及O2·-产生速率随盐处理浓度的增加而增加.NaCl处理对番茄幼苗的生长具有抑制作用,非气孔因素是引起光舍下降的主要因素,抗氧化酶活性不断增加以清除盐胁迫产生活性氧类,使番茄幼苗可以在盐胁迫条件下生存. 相似文献
149.
AgNO_3对梨叶片不定梢再生过程中抗氧化酶活性的影响 总被引:1,自引:0,他引:1
为探讨AgNO3在离体培养物形态发生中的作用,以金水和金花梨组培苗为外植体,研究了不同质量浓度AgNO3对梨叶片再生不定梢过程中抗氧化酶活性的影响。结果表明,0.1mg/LAgNO3能明显提高金水叶片不定梢再生率和再生数;金花叶片不定梢再生有效促进的AgNO3为0.1~0.5mg/L。经AgNO3处理后,2品种抗氧化物酶活性与对照差异显著。在暗培养期间,叶片中过氧化氢酶(CAT)和过氧化物酶(POD)活性均有较大幅度变化,特别是经0.1mg/LAgNO3处理后,金花叶片中POD活性及金水叶片中CAT活性增幅均高于其余3个处理。叶片中O·2产生速率和H2O2含量也增加但上升幅度不及对照。在进入光培养阶段后,添加适当的AgNO3可提高叶片原有的超氧化物歧化酶(SOD)峰值,且H2O2含量和O·2产生速率随之下降,但较高含量AgNO3处理易引起H2O2含量和O·2产生速率回升。虽然品种间抗氧化物酶活性变化不完全一致,但通过比较发现0.1mg/LAgNO3对提高金花和金水叶片抗氧化物酶活性效果最佳。 相似文献
150.
Raquel P. F. Guiné Susana Matos Fernando J. Gonçalves Daniela Costa Mateus Mendes 《International Journal of Fruit Science》2018,18(2):199-214
ABSTRACTThe study aimed at evaluating the influence of different production conditions, conservation, and extraction procedures on the total phenolic compounds and antioxidant activity of blueberries by DPPH and ABTS methods. The production factors considered were origin, altitude of the farm location, and age of the bushes. The conservation conditions considered were freezing as opposed to the fresh product. The extraction procedures included two different solvents and two orders of extraction. The data analysis was carried out by training artificial neural networks to model the data and extract information from the model.The results obtained revealed that the type of extract and the order of extraction influenced the concentrations of phenolic compounds as well as the antioxidant activity of the different samples studied. Also the origin of the farms from where the blueberries were harvested significantly influence those properties, showing that the blueberries from Oliveira do Hospital had less phenolic compounds and lower antioxidant activity. Also older bushes at higher altitudes seem to produce berries richer in these properties. Regarding conservation, no influence was observed for phenols but a slight influence could be detected for antioxidant activity. 相似文献