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为探讨温度对有水保活大口黑鲈代谢与肌肉品质的影响,研究了不同丁香酚浓度对大口黑鲈的麻醉效果。选取最佳浓度麻醉大口黑鲈,分别在5,10,15和20 ℃的条件下保活,测定了不同温度下的存活率、氨氮含量、血液生化指标与肌肉品质的变化。结果显示:大口黑鲈的较佳丁香酚浓度为18 mg/L,在5 ℃保活72 h存活率为0,在10、15和20 ℃下保活96 h后的存活率分别100%,75%和0%;随着保活时间延长,与15 ℃,20 ℃组相比,10 ℃组的总氨氮降低24.12%~51.24%,血糖含量先增加后下降,保活72 h后,10 ℃处理组血清中皮质醇、谷草转氨酶、谷丙转氨酶、碱性磷酸酶和尿素氮分别比20 ℃组低260.44 pg/mL、52.54 mmol/L、8.76 mmol/L、3.26 mmol/L和8.22 mmol/L(p<0.05),而溶菌酶、总抗氧化能力和谷胱甘肽过氧化物酶含量均显著高于其它组(p<0.05);10 ℃肝脏HSP90的表达量显著低于15 ℃和20 ℃;肌肉指标中,15 ℃和20 ℃组糖原、粗蛋白含量和pH显著低于10 ℃组。表明10 ℃保活条件下大口黑鲈抗氧化物酶活性增强,应激降低,肌肉品质影响较小。因此,10 ℃适合大口黑鲈的长途保活运输。 相似文献
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目的 检测水产品及养殖水中丁香酚类化合物。方法 应用食品补充检验方法BJS 201908《水产品及水中丁香酚类化合物的测定》,以海水鱼、淡水鱼、海水虾、淡水虾及养殖水作为基质,测定6种丁香酚类化合物的含量。结果 通过对实际样品测定后发现,在水产品中检出了丁香酚类化合物,主要为丁香酚,检出率为28.9%,其中海水鱼相对突出。结论 本研究为丁香酚作为渔用麻醉剂提供了方法论,为丁香酚类化合物在水产运输的合理使用提供理论依据。 相似文献
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为了确定大口黑鲈成鱼适合的麻醉方式和麻醉剂量,研究了不同浓度的丁香酚和MS-222对大口黑鲈的静水麻醉效果。在最适麻醉质量浓度下模拟运输24 h,记录24 h存活率并测定麻醉0.5、4、8、16和24 h后的血清生化指标、水质p H、氨氮以及麻醉剂的残留量。结果表明:随着丁香酚和MS-222浓度增加,入麻时间缩短,复苏时间延长;丁香酚和MS-222的最适质量浓度分别为18~20 mg/L、50~60 mg/L时,两麻醉组模拟运输和复苏24 h后的成活率为100%,显著高于无麻醉运输组的80%和90%(p<0.05);随着麻醉时间延长,丁香酚和MS-222组血清中的皮质醇(COR)分别从336.83pg/m L下降到291.41pg/m L,从286.11上升到367.05pg/m L(p<0.05),丁香酚组血清中的COR显著低于对照组;葡萄糖分别从14.36、7.48 mg/dL下降到7.36、3.11 mg/dL(p<0.05),而丁香酚组中乳酸脱氢酶(LDH)、碱性磷酸酶(AKP)、谷草转氨酶(GOT)、尿素氮(BUN)的浓度显著低于MS-222组(p<0.05);残留检测结果表明在麻醉0.5h时,鱼肉中丁香酚含量达到最大值5.14mg/kg,在清水中复苏1d时丁香酚残留量为0.45mg/kg;而MS-222组在8 h残留量达到最大值为36.24 mg/kg,复苏4 d时基本消除完全。结果显示,丁香酚剂量小,代谢快,在诱发氧化应激和组织损伤时有较少的副作用。 相似文献
5.
High‐performance thermosets with tailored properties derived from methacrylated eugenol and epoxy‐based vinyl ester 下载免费PDF全文
Yuehong Zhang Yuzhan Li Vijay Kumar Thakur Zhenhua Gao Jiyou Gu Michael R Kessler 《Polymer International》2018,67(5):544-549
A renewable chemical, eugenol, is methacrylated to produce methacrylated eugenol (ME) employing the Steglich esterification reaction without any solvent. The resulting ME is used as a low‐viscosity co‐monomer to replace styrene in a commercial epoxy‐based vinyl ester resin (VE). The volatility and viscosity of ME and styrene are compared. The effect of ME loading and temperature on the viscosity of the VE–ME resin is investigated. Moreover, the thermomechanical properties, curing extent and thermal stability of the fully cured VE–ME thermosets are systematically examined. The results indicate that ME is a monomer with low volatility and low viscosity, and therefore the incorporation of ME monomer in VE resins allows significant reduction of viscosity. Moreover, the viscosity of the VE–ME resin can be tailored by adjusting the ME loadings and processing temperature to meet commercial liquid molding technology requirements. The glass transition temperatures of VE–ME thermosets range from 139 to 199 °C. In addition, more than 95% of the monomer is incorporated and fixed in the crosslinked network structure of VE–ME thermosets. Overall, the developed ME monomer exhibits promising potential for replacing styrene as an effective low‐viscosity co‐monomer. The VE–ME resins show great advantages for use in polymer matrices for high‐performance fiber‐reinforced composites. This work is of great significance to the vinyl ester industry by providing detailed experimental support. © 2018 Society of Chemical Industry 相似文献
6.
Maria Jos G. Fernandes Renato B. Pereira David M. Pereira A. Gil Fortes Elisabete M. S. Castanheira M. Sameiro T. Gonalves 《International journal of molecular sciences》2020,21(23)
Eugenol, the generic name of 4-allyl-2-methoxyphenol, is the major component of clove essential oil, and has demonstrated relevant biological potential with well-known antimicrobial and antioxidant actions. New O-alkylated eugenol derivatives, bearing a propyl chain with terminals like hydrogen, hydroxyl, ester, chlorine, and carboxylic acid, were synthesized in the present work. These compounds were later subjected to epoxidation conditions to give the corresponding oxiranes. All derivatives were evaluated against their effect upon the viability of insect cell line Sf9 (Spodoptera frugiperda), demonstrating that structural changes elicit marked effects in terms of potency. In addition, the most promising molecules were evaluated for their impact in cell morphology, caspase-like activity, and potential toxicity towards human cells. Some molecules stood out in terms of toxicity towards insect cells, with morphological assessment of treated cells showing chromatin condensation and fragmentation, which are compatible with the occurrence of programmed cell death, later confirmed by evaluation of caspase-like activity. These findings point out the potential use of eugenol derivatives as semisynthetic insecticides from plant natural products. 相似文献
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受我国南北气候、地理环境和养殖条件的限制,鲜活水产品为满足不同市场的需求,需要经过长途运输。而运输过程中鲜活水产品受应激胁迫、机体受伤感染、水质恶化等因素影响,不仅引起水产品存活率降低,而且造成产品质量下降。丁香酚有较强的麻醉作用,广泛应用于口腔牙科麻醉,现也作为渔用麻醉剂应用到鲜活水产品运输过程中。虽然我国逐渐开展丁香酚应用、残留检测、风险评估等方面的研究,但关于水产品中麻醉剂丁香酚从应用到残留风险评估的综合性研究综述较少。本文旨在通过对丁香酚国内外标准规定、使用现状、麻醉机理和应用、残留检测方法、残留风险评估以及前景展望等方面进行说明和探讨,以期为我国丁香酚在水产养殖运输环节中的合理使用提供依据和参考。 相似文献
9.
Jianglei Qin Hongzhi Liu Pei Zhang Michael Wolcott Jinwen Zhang 《Polymer International》2014,63(4):760-765
In this study, an epoxy based on eugenol and an anhydride curing agent based on rosin were prepared. Curing of the eugenol epoxy with a commercial anhydride curing agent and with the rosin‐derived anhydride curing agent was studied. For comparison, a commercial bisphenol A type epoxy, DER353, was also selected in the curing study. The syntheses of the eugenol epoxy and rosin anhydride were investigated and the chemical structures of the products and intermediates were characterized using 1H NMR and Fourier transform infrared spectroscopies. Non‐isothermal curing of the eugenol epoxy with hexahydrophthalic anhydride and the rosin‐derived maleopimaric acid was studied using differential scanning calorimetry. Thermomechanical properties and thermal stability of the cured epoxy resins were evaluated using dynamic mechanical analysis and thermogravimetric analysis, respectively. Addition of 2‐ethyl‐4‐methylimidazole as catalyst greatly decreased the curing temperature and promoted the completion of cure reactions. The results suggest that the eugenol epoxy and the bisphenol A type epoxy have similar reactivity, dynamic mechanical properties and thermal stability. © 2013 Society of Chemical Industry 相似文献
10.
为探讨植物精油对枇杷采后炭疽菌抑制的效果及其机理,分别用丁香酚、柠檬醛和香芹酚对尖孢炭疽菌进行体外处理,筛选出丁香酚为最优抑制剂并研究了其对尖孢炭疽菌外渗率、核酸泄漏及蛋白质的影响。以枇杷为供试材料,接种尖孢炭疽菌后分别用0.5、1.0、2.5、5.0μL/L的丁香酚熏蒸处理,统计病害发生率及病斑直径,并研究了丁香酚对枇杷品质的影响。结果表明:在体外实验中,3种供试精油对尖孢炭疽菌均有明显的抑制作用,48μL/L丁香酚可以完全抑制尖孢炭疽菌的生长,且在一定程度上造成了菌内细胞内容物的渗出。在丁香酚对枇杷果实采后炭疽病抑制效果实验中发现,贮藏6 d时,1μL/L丁香酚处理组病斑直径及病害发生率显著低于对照组,病斑直径仅为6.41 mm,病害发生率为66.67%。丁香酚对枇杷品质影响方面,其能够显著抑制采后枇杷质量损失率的上升及VC含量下降(P0.05),但对枇杷的颜色、硬度、可溶性固形物及可滴定酸等品质指标影响不显著(P0.05)。 相似文献