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排序方式: 共有1531条查询结果,搜索用时 31 毫秒
1.
为解决草莓采后果实腐烂变质问题,将草莓置于甘草提取液、乳酸钙溶液、蒸馏水中浸泡1 min,取出晾干后常温贮藏,比较3组草莓失重率、腐烂率、可溶性糖、维生素C含量、超氧化物歧化酶SOD活性的变化。与对照组相比,贮藏7天后,甘草提取液组草莓失重率降低34.72%、腐烂率降低31.56%、可溶性糖含量提高99.10%、维生素C含量提高154.55%、超氧化物歧化酶SOD活性提高206.24%,乳酸钙处理和甘草提取液保鲜效果没有显著差异(P>0.05)。实验期内,2种处理方法均可提高草莓保鲜效果。 相似文献
2.
James W. Wynne Chris Stratford Joel Slinger Francisca Samsing Megan Rigby Russell McCulloch Petra Quezada-Rodriguez Richard S. Taylor 《Journal of fish diseases》2020,43(1):39-48
Hydrogen peroxide (H2O2) is a commonly used treatment for a range of parasitic diseases of marine finfish, including amoebic gill disease (AGD). While this treatment is partially effective at reducing parasite load, H2O2 can have detrimental effects on the host under certain conditions. Treatment temperature and dose concentration are two factors that are known to influence the toxicity of H2O2; however, their impact on the outcome of AGD treatment remains unclear. Here, we investigated the effects of treatment temperature (8, 12 or 16°C) and dose concentration (750, 1,000, 1,250 mg/L) on the efficacy of H2O2 to treat AGD. We demonstrated that a 20-min bath treatment of H2O2 at all doses reduced both parasite load and gross gill score significantly. Parasite load and gross gill score were lowest in the 1,000 mg/L treatment performed at 12°C. At the high dose and temperature combinations, H2O2 caused moderate gill damage and a significant increase in the plasma concentration of electrolytes (sodium, chloride and potassium). Taken together, our study demonstrates that higher H2O2 treatment temperatures can adversely affect the host and do not improve the effectiveness of the treatment. 相似文献
3.
通过表征受碱性过氧化氢降解的木质素磺酸盐,探索高效低耗的木质素降解条件。木质素磺酸盐与含有H2O2的0.5、1.0、2.0 mol/L的NaOH溶液分别在90、170℃下反应2 h。结果表明:碱性过氧化氢处理后木质素磺酸盐的Mw(重均相对分子质量)和Mn(数均相对分子质量)降低,而在170℃,1 mol/L NaOH溶液条件下获得最大程度的降解。木质素磺酸盐的相对分子质量在降解后分布相对集中,这表明木质素磺酸盐可直接用于开发木质素基材料而无需进一步分离。用碱性过氧化氢降解后,甲氧基摩尔分数降低。在170℃、2 mol/L NaOH溶液条件下4步加入过氧化氢,降解得到的木质素甲氧基摩尔分数下降57.4%。碱性硝基苯氧化的结果也表明在170℃下用2 mol/L NaOH溶液和4步添加H2O2处理后会得到最低的香草醛和香草酸产率,表明该条件下非浓缩的木质素结构被有效破坏。FTIR结果显示木质素的芳香结构消失。木质素磺酸盐利用碱性过氧化物降解,最佳条件是在2 mol/L NaOH溶液和170℃条件下,分4步添加H2O2。 相似文献
4.
The effect of hydrogen peroxide (HP) and ozone (O3) treatment during barley steeping on the quality of malt produced from two barley varieties (GrangeR and AC Metcalfe) by micro-malting was investigated. The two steeping oxidation treatments that was observed to promote barley acrospire growth. Ozone treatment improved the malt enzyme activity of endo-protease, α-amylase, free beta-amylase and total limit dextrinase to differing extents, with GrangeR improving to a greater degree. HP treatment contributed to the increase of α-amylase, β-glucanase and endo-protease. Surprisingly, HP or ozone oxidation during malting resulted in different and novel outcomes for total beta-amylase in GrangeR and AC Metcalfe. In GrangeR, total beta-amylase activity reduced with respect to the control in both treatments. In comparison with AC Metcalfe there was a substantial increase of 78% with HP and 90% O3 in total beta-amylase activity. Malt quality including wort free amino nitrogen, β-glucan, turbidity and diastatic power was differentially increased by the oxidation induction treatment during steeping in malting. Gene expression analysis indicated that the effects of the steep oxidation treatments on enzyme and malt quality were putatively linked with the up-regulation of certain genes involved in GA synthesis (GA20ox1) and ABA catabolism (ABA8′OH). Barley grain germination assay results also showed that moderate HP induction could improve barley germination tolerance to the ABA effect. Malting including steep oxidation induction was shown to be beneficial to malt quality by improving the resultant wort quality and the efficiency of the beer brewing process. These observations point the way towards improving malt quality and the efficiency of the malting process. 相似文献
5.
AIM: To explore the effect of inositol 1, 4, 5-trisposphate receptor (IP3R) in luteinizing hormone-epidermal growth factor receptor (LH-EGFR)-induced oocyte meiotic resumption. METHODS: Models of mouse cumulus-oocyte complexs (COCs) culture and follicle culture in vitro were generated to study the effects of 2-aminoethyl diphenyl borate (2-APB) and heparin (IP3R specific inhibitors) on LH/EGF-induced oocyte meiotic resumption and EGF-induced cumulus cell expansion. Real-time PCR was used to detect the mRNA expression of cumulus expansion-related factors. The changes of the intracellular calcium level were monitored using Fluo 3-AM, and the cGMP level was measured by ELISA. RESULTS: The inhibitors of IP3R, 2-APB and heparin, dramatically reversed EGF-induced oocyte maturation (P <0.05) and decreased cGMP levels in COCs (P <0.05). In addition, 2-APB and heparin reversed EGF-induced cumulus expansion, and significantly inhibited EGF-induced cumulus expansion-related factor expression (P <0.05). The activation of IP3R increased intracellular calcium level, and the study found that 2-APB and heparin dramatically reversed EGF-induced elevation of calcium level in cumulus cells (P <0.05). Follicular culture in vitro showed that 2-APB and heparin significantly reversed the LH-induced oocyte maturation (P <0.05). CONCLUSION: LH-EGFR signaling pathway increases calcium level in cumulus cells through IP3R, resulting in meiotic resumption. 相似文献
6.
近几年来‘王林’苹果苦痘病的发病率较高,为了探索防治办法,2018—2019年在瓦房店市驼山乡大魏村‘王林’苹果园进行施用“聚能螯合钙+硅”+生物有机肥试验。结果表明:第1年好果率达到90.2%,比对照提高15.0%;第2年分别为96.82%、22.23%。病果的病斑数也明显减少。 相似文献
7.
水培试验表明,稀土有平衡树体钙素营养的作用,在钙浓度低时,稀土能促进果树对钙的吸收,在钙浓度高时,可在一定程度上抑制果树对钙的吸收。田间喷钙可促进果树对氮、钙、锌的吸收,并增加果实中钙的浓度。稀土、钙混合液浸果可使果实中钙浓度增加0.165%,保鲜率比对照增加26%。 相似文献
8.
9.
蓖麻蚕滞育与过氧化氢代谢的关系 总被引:1,自引:1,他引:0
为了探讨蓖麻蚕滞育的机理,研究了蓖麻蚕蛹H2O2代谢的变化,并比较了在5℃冷藏滞育条件下的差异。结果表明,常温环境蓖麻蚕蛹期的H2O2含量呈减少趋势,第3~5天急速变化,超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性在第5天出现活性峰,故蛹期第3~5天是蓖麻蚕生理变化的一个敏感时期。第3天开始蛹滞育条件5℃冷藏,雄蛹在30 d前后、雌蛹在80 d左右H2O2含量出现快速改变;SOD和CAT活性一直呈下降趋势,但自30 d开始CAT活性出现快速下降过程,5℃冷藏30 d是蓖麻蚕蛹H2O2代谢的临界期生理时间,这与蚕蛹的30 d冷藏阈值时间吻合。 相似文献
10.