Coumarin and eugenol ameliorate LPS-induced inflammation in RAW 264.7 cells via modulating the NLRP3 inflammasome pathway

Objective:To investigate the underlying mechanism of anti-inflammatory action of coumarin and eugenol in lipopolysaccharide(LPS)-stimulated RAW 264.7 cells.Methods:RAW 264.7 cells were treated with 2.5μg/mL of LPS,50μM of coumarin,and 50μM eugenol for 24 h.The viability of the cells was assessed using MTT assay.The production of nitric oxide was determined using Griess reagent and DCFH-DA was used to measure the production of reactive oxygen species.The protein expression of NLRP3,IL-1β,NF-κB,and cyclooxygenase 2 was assessed using Western blot analysis.Results:Coumarin and eugenol showed anti-inflammatory effects against LPS-induced inflammatory response by ameliorating the expression of NLRP3 inflammasome and NF-κB,which further led to a subsequent reduction in IL-1β,nitric oxide,and reactive oxygen species.Conclusions:Coumarin and eugenol exert their anti-inflammatory activities by modulating the NLRP3 inflammasome pathway and NF-κB.These compounds may have promising therapeutic applications for the treatment of various inflammatory diseases.

Eugenol targeting CrtM inhibits the biosynthesis of staphyloxanthin in Staphylococcus aureus

Staphylococcus aureus is a serious foodborne pathogen threatening food safety and public health.Especially the emergence of methicillin-resistant Staphylococcus aureus(MRSA)increased the difficulty of S.aureus treatment.Staphyloxanthin is a crucial virulence factor of S.aureus.Blocking staphyloxanthin production could help the host immune system counteract the invading S.aureus cells.In this study,we first screened for staphyloxanthin inhibitors using a virtual screening method.The outcome of the virtual screening method resulted in the identification of eugenol(300μg/mL),which significantly inhibits the staphyloxanthin production in S.aureus ATCC 29213,S.aureus Newman,MRSA ATCC 43300 and MRSA ATCC BAA1717by 84.2%,63.5%,68.1%,and 79.5%,respectively.The outcome of the growth curve assay,field-emission scanning electron,and confocal laser scanning microscopy analyses confirmed that eugenol at the test concentration did not affect the morphology and growth of S.aureus.Moreover,the survival rate of S.aureus ATCC 29213 and MRSA ATCC 43300 under H_(2)O_(2) pressure decreased to 51.9%and 45.5%in the presence of eugenol,respectively.The quantitative RT-PCR and molecular simulation studies revealed that eugenol targets staphyloxanthin biosynthesis by downregulating the transcription of the crtM gene and inhibiting the activity of the CrtM enzyme.Taken together,we first determined that eugenol was a prominent compound for staphyloxanthin inhibitor to combat S.aureus especially MRSA infections.

Enhancement of the Antigenotoxic and Antioxidant Actions of Eugenol from Spice Clove and the Stabilizer Gum Arabic on Colorectal Carcinogenesis

Spices are defined as any aromatic condiment of plant origin used to alter the flavor and aroma of foods. Besides flavor and aroma, many spices have antioxidant activity, mainly related to the presence in cloves of phenolic compounds, such as flavonoids, terpenoids and eugenol. In turn, the most common uses of gum arabic are in the form of powder for addition to soft drink syrups, cuisine and baked goods, specifically to stabilize the texture of products, increase the viscosity of liquids and promote the leavening of baked products (e.g., cakes). Both eugenol, extracted from cloves, and gum arabic, extracted from the hardened sap of two species of the Acacia tree, are dietary constituents routinely consumed virtually throughout the world. Both of them are also widely used medicinally to inhibit oxidative stress and genotoxicity. The prevention arm of the study included groups: Ia, IIa, IIIa, Iva, V, VI, VII, VIII. Once a week for 20 weeks, the controls received saline s.c. while the experimental groups received DMH at 20 mg/kg s.c. During the same period and for an additional 9 weeks, the animals received either water, 10% GA, EUG, or 10% GA + EUG by gavage. The treatment arm of the study included groups Ib, IIb, IIIb e IVb, IX, X, XI, XII). Once a week for 20 weeks, the controls received saline s.c. while the experimental groups received DMH at 20 mg/kg s.c. During the subsequent 9 weeks, the animals received either water, 10% GA, EUG or 10% GA + EUG by gavage. The novelty of this study is the investigation of their use alone and together for the prevention and treatment of experimental colorectal carcinogenesis induced by dimethylhydrazine. Our results show that the combined use of 10% gum arabic and eugenol was effective, with antioxidant action in the colon, as well as reducing oxidative stress in all colon segments and preventing and treating genotoxicity in all colon segments. Furthermore, their joint administration reduced the number of aberrant crypts and the number of aberrant crypt foci (ACF) in the distal segment and entire colon, as well as the number of ACF with at least 5 crypts in the entire colon. Thus, our results also demonstrate the synergistic effects of 10% gum arabic together with eugenol (from cloves), with antioxidant, antigenotoxic and anticarcinogenic actions (prevention and treatment) at the doses and durations studied, in the colon of rats submitted to colorectal carcinogenesis induced by dimethylhydrazine.

Studies on Anesthetic Effect of Eugenol on Juvenile Fenneropenaeus chinensis

[Objective] The aim of the study is to seek a good anesthetic to Fenneropenaeus chinensis. [Method] The anesthetic effect of eugenol to juvenile Fenneropenaeus chinensis was investigated. [Result] The juveniles could be effectively anaesthetized by 50-400 mg/L eugenol aqueous solution with temperature of 24 ℃. Within the concentration range of 50-400 mg/L, the increase of the eugenol concentration could shorten the time required for anesthesia, meanwhile could prolong the time for recovery. The recovered rate of prawn reached 100% when the eugenol concentration was lower than 200 mg/L, while the recovered rate of prawn was just 66.67% when the eugenol concentration was higher than 400 mg/L. The survival rate of prawns in test group was 100% from the observation of three consecutive days. For the specific dose, the anesthetic effect enhanced with the increase of water temperature (18-27℃). [Conclusion] Eugenol is a safe and efficient anesthetics that can be applied in genetic breeding of prawn.

Cold Stress-induced Glucosyltransferase CsUGT78A15 is Involved in the Formation of Eugenol Glucoside in Camellia sinensis

Eugenol is a natural phenolic compound known for its health-promoting properties and its ability to add a floral scent to tea plants.Plant eugenol glycosides have been identified and shown to make important contributions to fruit floral quality.However,the details of their biosynthesis and metabolism in tea plants are still unknown.Here,eugenol glucoside was unambiguously identified as a native metabolite in the tea plant,and its biosynthesis was shown to be induced by low temperature treatment.Through the analysis of UGTs induced by low temperature,the glycosyltransferase CsUGT78A15 was identified in tea,and its encoded protein was shown to catalyze the glucosylation of eugenol.Vmax/Km ratios showed that eugenol was the most suitable substrate for CsUGT78A15.Sugar donor preference analysis showed that CsUGT78A15 had a higher selectivity for glucose,followed by galactose and glucuronic acid.The expression of CsUGT78A15was correlatedwith the accumulation of eugenol glucoside in different tissues and genotypes of tea.Down-regulation of CsUGT78A15 led to a decreased eugenol glucoside content under cold stress,indicating that CsUGT78A15 plays an important role in the biosynthesis of eugenol glucoside under cold stress.The identification of eugenol glucoside in the tea plant and the discovery of a cold stress-induced eugenol glucosyltransferase in tea provide the foundation for the improvement of tea flavor under cold stress and the biotechnological production of eugenol glucoside.

MgFe hydrotalcites-derived layered structure iron molybdenum sulfide catalysts for eugenol hydrodeoxygenation to produce phenolic chemicals

Hydrodeoxygenation（HDO） is an effective alternative to produce value-added chemicals and liquid fuels by removing oxygen from lignin-derived compounds. Sulfide catalysts have been proved to have good activity for the HDO and particularly high selectivity to phenolic products. Herein, we presented a novel way to prepare the layered structure sulfide catalysts（MgFeMo-S） derived from MgFe hydrotalcites via the intercalation of Mo in consideration of the memory effect of the calcined hydrotalcite. By varying the Mg/Fe mole ratio, a series of MgFeMo-S catalysts were successfully prepared and characterized by nitrogen adsorption/desorption isotherms, X-ray diffraction（XRD）, transmission electron microscopy（TEM）,and inductively coupled plasma optical emission spectrometer（ICP-OES）. The characterization results indicated that the MgFeMo-S catalyst has retained the unique layered structure, which can facilitate uniform dispersion of the MoS2 species on both the surface and interlayer of the catalysts. For the HDO of eugenol, the Mg1Fe2Mo-S catalysts exhibited the best HDO activity among all the catalysts due to its higher active metal contents and larger pore size. The HDO conversion was 99.6% and the yield of phenolics was 63.7%, under 5 MPa initial H2 pressure（measured at RT） at 300 ℃ for 3 h. More importantly,MoS2 species deposited on the interlayer galleries in the MgFeMo-S catalysts resulted in dramatically superior HDO activity to MoS2/Mg1Fe2-S catalyst. Based on the mechanism investigation for eugenol, the HDO reaction route of eugenol under sulfide catalytic system has been proposed for the first time. Further applicability of the catalyst on HDO of more lignin-derived compounds was operated, which showed good HDO activity and selectivity to produce aromatic products.

<i>In Vitro</i>Efficacy of Clove Oil and Eugenol against <i>Staphylococcus</i>spp and <i>Streptococcus mutans</i>on Hydrophobicity, Hemolysin Production and Biofilms and their Synergy with Antibiotics

The present study aimed to evaluate Syzygium aromaticum (clove) plant extract, clove oil and eugenol for their antibacterial activity and their potential to eradicate bacterial biofilms alone and in combination with antibiotics. Anti-bacterial efficacy of S. aromaticum extract, clove oil and eugenol was evaluated as minimum inhibitory concentration (MIC) and subsequently sub-MICs was selected for inhibition of virulence factors against test bacterial strains. Biofilm cultivation and eradication was assayed using XTT reduction in 96-well microtiter plate. Checkerboard method was used to study the interaction between essential oils and antibiotics. Staphylococcus aureus MTCC3160, Staphylococcus epidermidis MTCC435, Staphylococcus sciuri (SC-01), Staphylococcus auricularis (SU-01) and Streptococcus mutans MTCC497 were found strong biofilm former among all the test bacterial strains. The potency of test agents was found in the order of eugenol > clove oil > S. aromaticum methanolic extract. Sub-MIC (0.5 × MIC) of clove oil and eugenol showed a significant reduction in cell surface hydrophobicity (p < 0.05) and hemolysin production in the test bacterial strains. Eugenol showed no increase in sessile MIC (SMIC) against S. auricularis (SU-01), S. epidermidis MTCC435 and S. mutans MTCC497 compared to planktonic MIC (PMIC). Antibiotics (vancomycin and azithromycin) exhibited upto 1000-folds increased in SMIC compared to PMIC against all the test bacterial strains. Synergy was observed between eugenol and antibiotics (vancomycin/azithromycin) against all the test bacterial strains in both planktonic and sessile mode. Highest synergy was exhibited between eugenol and azithromycin in planktonic mode (FICI value 0.141). Further, microscopy also confirmed the spectacular effect of combination treatment on pre-formed S. aureus MTCC3160 and S. mutans MTCC497 biofilms. These findings highlighted the promising role of clove oil and eugenol alone and in combination on pathogenic bacterial biofilms.

Antiasthmatic Effect of Eugenol （4-Allyl-2-Methoxyophenol） Mediated by Both Bronchodilator and Immunomodulatory Properties

Eugenol, an aromatic product, exhibits anti-inflammatory properties, however, little is known about its effect in allergic inflammation mediated by Th2-type cells and cytokines. We examined the pharmacological potential of this compound in a murine model of respiratory allergy to Bt （Blomia tropicalis）. For this, AJ mice were sensitized （100μg/animal s.c.） and challenged （10 μg/animal i.n.） with Bt mite extract. Sensitized animals were treated or not with eugenol （20, 40 or 80 mg/kg） and the following parameters were analyzed： number of total cells in BAL （bronchoalveolar lavage）; EPO （eosinophil peroxidase activity） and histopathological changes in the lungs; serum level of specific IgE, IgG1 and IgG2a and; concentration of Th2 cytokines on BAL and spleen cultures. In addition, the capability ofeugenol in relaxing tracheal smooth muscle was also evaluated. Our results showed that treatment with eugenol significantly reduced the airway inflammation, decreasing the cellular infiltrate, EPO and mucus in the lungs, as well as the production of Th2 cytokines. It was also demonstrated a dilator effect of eugenol observed by the relaxation of normal and hyper-reactivity isolated trachea upon carbachol stimulation. These results suggest that eugenol has potential as an anti-asthmatic drug by both bronchodilator and immunomodulatory properties.

Complexation of Eugenol(EG),as Main Component of Clove Oil and as Pure Compound,withβ-and HP-β-CDs

Eugenol, both in its pure form (EG) and included in essential clove oil (CO) was successfully solubilized in aqueous solution by forming inclusion complexes with β-cyclodextrins (β-CDs) and its modified hydroxy-propyl-β-CDs (HP-β-CDs). To investigate the molecular association between β-CDs/HP-β-CDs with pure EG and essential CO, phase solubility studies were undertaken. Essential CO formed insoluble complexes with β-CDs, but not with HP-β-CDs. The work clearly demonstrates complexes formation follow an order higher than 1:1 when high essential CO and β-CDs concentrations were used, however it was 1:1 in the case of essential CO-HP-β-CDs complexes. When pure EG was studied the results indicated that EG could form 1:1 inclusion complexes with β-CDs and HP-β-CDs. Based on the studies, the Kc values for pure EG were 4555 ± 225 M-1 and 10,633 ± 614 M-1 for β-CDs and HP-β-CDs, respectively, and 2005 ± 199 M-1 for essential CO-HP-β-CDs. These finding indicate that CDs are suitable for encapsulating EG.

Extraction of Eugenol from Essential Oils by In Situ Formation of Deep Eutectic Solvents:A Green Recyclable Process

Eugenol is extensively utilized in chemical industry.In actual production,it is mainly separated from clove essential oils(EOs)through acid-base solutions.In this work,a simple,rapid and effective extraction process was developed for the extraction of eugenol from EOs samples by directly forming deep eutectic solvents(DESs)without using acid-base solutions.The proposed process is designed to dissolve EOs in n-hexane and eugenol was highly selective extracted into DESs with tetrabutylammonium chloride(TBAC).Hydrogen bonds in DESs can be broken by addition of water,resulting in a separation of the two phases,thus obtaining a hydrophobic yellowish eugenol in the upper layer.The quaternary ammonium salt in the lower aqueous solution can be reused after recovery.The most determining influence factors such as the structure of quaternary ammonium salt,the mole ratio of quaternary ammonium salt to eugenol and the amount of n-hexane were investigated.The forming conditions of DESs were studied by Box-Behnken design(BBD).Experiment was carried out under the optimal conditions and good experimental result was demonstrated by the developed process,a high extraction recovery of 92.51% and the purity was about 98.50%,which verifies the excellent performance for the proposed process.

常温下三卡因和丁香酚对条纹小鲃的麻醉效果研究

为提高条纹小鲃在常温下养殖生产操作及运输中的存活率,将野外采集的条纹小鲃经循环水暂养驯化14 d,在水温(25.0±0.5)℃下,开展三卡因和丁香酚对体质量(0.28±0.09)g条纹小鲃的有效麻醉试验:分别经质量浓度为140 mg/L的三卡因、质量浓度为25 mg/L的丁香酚深度麻醉后的离水暴露试验,分别经质量浓度为10 mg/L的三卡因、质量浓度为8 mg/L的丁香酚镇静后的模拟运输试验,探讨常温下不同操作目的2种麻醉剂的应用效果。试验结果显示,三卡因和丁香酚麻醉条纹小鲃的有效质量浓度分别为100~140 mg/L、20~30 mg/L。经质量浓度140 mg/L三卡因、质量浓度25 mg/L丁香酚深度麻醉的条纹小鲃,在空气中分别暴露6、8 min内复苏率为100%。选择三卡因质量浓度10 mg/L、丁香酚质量浓度8 mg/L模拟运输,48 h内均以鱼水质量比1∶15效果最佳;如运输72 h,可使用三卡因麻醉,以鱼水质量比1∶20效果最佳,存活率达90.74%。试验结果表明,三卡因和丁香酚均对条纹小鲃有良好的麻醉效果,在实际应用中应根据不同的操作目的并结合其他要素,选用合适的麻醉质量浓度。

Quantification of eugenol and bancroftione in Caryophylli Fructus using high-performance liquid chromatography

For the first time, we have utilized high-performance liquid chromatography （HPLC） to simultaneously quantify the eugenol and bancroffione in Caryophylli Fructus. The optimized parameters included： Inertsil ODS-4 column （150 mm×4.6 mm, 5 μm）; column temperature： 35 ℃; mobile phase： methanol water （65：35, v/v）; flow rate： 1.0 mL/min; detection wavelength： 280 nm. Eugenol and bancroftione showed good linear relationships with peak areas within the range of （0.0998 0.8982） mg/mL （r = 0.9999） and （0.1474-1.3266） mg/mL （r = 0.9999）, respectively. The average recoveries were 102.52% and 100.96% for eugenol and bancroftione, respectively. Our results showed that the established method is simple, rapid, and accurate with good reproducibility to evaluate the quality of Caryophylli Fructus.

MS-222和丁香酚胁迫对四指马鲅幼鱼鳃及肝脏组织微观结构的影响

【目的】探究不同质量浓度的MS-222和丁香酚胁迫对四指马鲅(Eleutheronema tetradactylum)幼鱼鳃和肝脏组织损伤的影响。【方法】设置7个浓度的MS-222(20、30、35、40、45、50、60 mg/L)和7个浓度的丁香酚(5、10、20、25、30、40、50 mg/L),分析不同处理对平均全长4.5(±0.5)cm、平均体质量1.5(±0.5)g的四指马鲅幼鱼的静水麻醉效应。【结果】当MS-222浓度不小于35 mg/L时,麻醉467 s后幼鱼开始出现应激反应;浓度为50 mg/L时可将部分幼鱼诱导进入麻醉期,浓度为60 mg/L时可在293 s后将全部幼鱼诱导进入麻醉期。丁香酚浓度不小于25 mg/L时,麻醉291 s后幼鱼开始出现应激反应;浓度为30 mg/L时可将部分幼鱼诱导进入麻醉期;浓度为40、50 mg/L时,分别可以在194 s和102 s将全部幼鱼诱导进入麻醉期。随着MS-222和丁香酚浓度的升高,幼鱼进入同一麻醉时期的时间显著缩短(P<0.05),高浓度下四指马鲅幼鱼进入麻醉时期的时间过快,超过耐受值可能对鱼体产生一定毒害作用,导致鱼体死亡。观察幼鱼组织病理切片发现,随着MS-222和丁香酚浓度的升高,幼鱼肝细胞出现空泡,排列紊乱,核内可见核溶解,肝板结构不清;鳃小片弯曲,末端肿大,严重者可胀破、脱落。【结论】适度的麻醉剂量可以降低鱼体对外界环境的应激反应,减少耗氧,不同浓度的MS-222和丁香酚(5 mg/L除外)均可在3 min内对四指马鲅幼鱼产生镇静作用,当2种麻醉剂浓度过高、麻醉时间过长以及幼鱼长时间处于应激状态时,会出现死亡现象。

基于TMT技术的香芹酚和丁香酚杀螨机制分析

为了探究香芹酚和丁香酚的杀螨机制,试验首先设置香芹酚组、丁香酚组和阴性对照组共3组,每组3个重复,香芹酚组、丁香酚组和阴性对照组分别用0.15%丁香酚、0.05%香芹酚和液体石蜡处理疥螨4 h后提取疥螨蛋白质,蛋白质经还原烷基化、酶解及串联质谱标记(tandem mass tag, TMT)后进行高效液相色谱分离和液相色谱串联质谱分析;然后对香芹酚组/阴性对照组及丁香酚组/阴性对照组的差异表达蛋白进行分析,并对差异表达蛋白进行GO功能富集分析和KEGG信号通路富集分析;最后筛选与香芹酚、丁香酚杀螨相关的差异表达蛋白。结果表明:香芹酚组/阴性对照组共有蛋白4 692个,其中差异表达蛋白235个(上调蛋白113个,下调蛋白122个);丁香酚组/阴性对照组共有蛋白4 824个,其中差异表达蛋白103个(上调蛋白43个,下调蛋白60个)。香芹酚组/阴性对照组差异表达蛋白极显著富集(P<0.01)的GO二级条目包括平滑信号通路、从细胞核输出的蛋白质调节、氧化磷酸化等;显著富集(P<0.05)的GO二级条目包括核质转运的调节、细胞内蛋白质运输的调节、甘油酯生物合成过程等。丁香酚组/阴性对照组差异表达蛋白极显著富集(P<0.01)的GO二级条目包括tRNA修饰、ncRNA处理;显著富集(P<0.05)的GO二级条目包括细胞酰胺代谢过程、正向调节蛋白定位到细胞核、含蝶啶化合物分解代谢过程等。香芹酚组/阴性对照组差异表达蛋白显著富集(P<0.05)的KEGG信号通路包括α-亚麻酸代谢、卟啉与叶绿素代谢、癌症蛋白聚糖等。丁香酚组/阴性对照组差异表达蛋白显著富集(P<0.05)的KEGG信号通路包括核糖体、军团杆菌病。与香芹酚杀螨机制相关的GO二级条目为氧化磷酸化,磷脂酰甘油磷酸合成酶和细胞色素C氧化酶亚基1注释到这一过程中;与阴性对照组比较,香芹酚组的磷脂酰甘油磷酸合成酶显著上调(P<0.05),细胞色素C氧化酶亚基1显著下调(P<0.05)。与丁香酚杀螨机制相关的KEGG信号通路为核糖体,核糖体L23蛋白60S亚基、核糖体L32蛋白39S亚基、核糖体L3蛋白39S亚基、核糖体S16蛋白28S亚基、核糖体L1蛋白39S亚基注释到这一KEGG信号通路中;与阴性对照组比较,丁香酚组的上述蛋白均显著下调(P<0.05)。说明香芹酚杀螨机制与氧化磷酸化这一过程相关,丁香酚杀螨机制与核糖体蛋白表达相关。

阿司匹林丁香酚酯咀嚼片的稳定性试验

考察不同因素对阿司匹林丁香酚酯(Aspirin eugenol ester, AEE)咀嚼片稳定性的影响,为制剂临床应用、贮存及运输提供理论依据。按照2020年版《中华人民共和国兽药典》原料药物与制剂稳定性试验指导进行影响因素试验、加速试验和长期试验,考察AEE咀嚼片在不同试验条件下的外观性状、重量差异、脆碎度、有关物质含量及溶出度变化,用高效液相色谱法测定有关物质和主成分含量,紫外可见分光光度法测定溶出度。结果显示,影响因素试验及加速试验条件下,AEE咀嚼片的各项考察指标均无明显变化;长期试验中除AEE咀嚼片的含量与溶出度随时间延长有所降低,但仍符合质量标准要求,其他各项指标均无明显变化。表明AEE咀嚼片制备工艺可靠,24个月内稳定性良好,建议包装应密闭,宜置于干燥阴凉处存放,以保证产品稳定。

丁子香酚对人参黑斑病菌的抑制活性及其作用机制研究

黑斑病是人参上最重要的真菌病害之一,严重影响人参的产量与品质。本文采用菌丝生长速率法和孢子萌发法,研究了丁子香酚对人参黑斑病菌的抑制活性,并评价了对病菌相对电导率、丙二醛含量及抗氧化酶活性的影响。结果表明:丁子香酚对人参黑斑病菌的抑制作用显著,0.30 mg/mL时,对菌丝生长和孢子萌发的抑制率分别高达90.14%和94.40%;丁子香酚处理病原菌菌丝12 h后,其相对电导率和丙二醛(MDA)含量明显升高,分别为66.18%和1.83nmol/g;抗氧化酶过氧化物酶(POD)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)的活性峰值出现在24 h,分别为379.80、38.80和305.10 U/g。丁子香酚能够破坏细胞膜完整性、增强膜脂质过氧化反应、促使活性氧大量积累,从而诱导细胞死亡,发挥抑菌功能。本研究可为丁子香酚在人参黑斑病绿色防控中的合理应用提供参考,同时为人参黑斑病防控增加了用药选择。

桔小实蝇BdorOBP2对甲基丁香酚及其结构类似物的结合分析

本文研究了桔小实蝇Bactrocera dorsalis气味结合蛋白BdorOBP2对甲基丁香酚(ME)及其结构类似物的结合特性,以期为基于蛋白结构的新型引诱剂的分子设计提供靶标蛋白。本研究扩增获得气味结合蛋白BdorOBP2基因并进行序列分析。三维结构预测显示,BdorOBP2具有6个α螺旋,同时含有6个保守的半胱氨酸残基。荧光定量结果表明BdorOBP2在雌雄虫触角中的表达水平最高,同时在足、翅等组织中表现出性别差异表达特性,推测BdorOBP2具有识别性信息素和寄主挥发物的双重作用。在对BdorOBP2蛋白表达和纯化的基础上,采用荧光竞争结合试验分析了BdorOBP2与甲基丁香酚及其类似物的结合能力,结果显示BdorOBP2蛋白对丁香酚、异丁香酚、甲基丁香酚、异丁香酚甲醚等4种化合物的结合能力相当。BdorOBP2在感受寄主挥发物及性信息素过程中挥发重要作用,为基于靶标蛋白的新型行为调控剂的分子设计提供了重要参考。

食品级丁香酚微乳液相行为及其抑菌性

为提高丁香酚的亲水性和抑菌效果,以吐温为表面活性剂,乳酸为助表面活性剂,构建可无限稀释的丁香酚微乳液,并探究微乳化前后丁香酚抑制大肠杆菌和金黄色葡萄球菌的效果。拟三元相图的分析结果表明,与吐温-40和吐温-60相比,吐温-80更能有效增加微乳液单相区面积;乳酸的增溶效果随着乳酸添加量的增加而提高,当丁香酚与乳酸质量比为1∶3时,丁香酚微乳液单相区面积扩大至78.8%。抑菌特性研究结果显示:在一定范围内,随着吐温-80比例的降低,乳酸比例的增加,丁香酚微乳液的抑菌效果增强;当微乳液组分中丁香酚、乳酸与吐温-80的质量比为1∶3∶6时,质量分数0.05%的丁香酚可完全抑制2种受试细菌的生长,同时,该复合微乳液的抑菌活性显著高于不含乳酸的单一丁香酚微乳。研究开发的微乳液旨在为实现丁香酚的增溶增效提供可行的剂型,并有望用于食品防腐保鲜领域。

Synthesis of Eugenol Bio-based Reactive Epoxy Diluent and Study on the Curing Kinetics and Properties of the Epoxy Resin System

In this study, monoglycidyl silyl etherated eugenol(GSE) was synthesized as reactive epoxy diluent, and the chemical structure of GSE, intermediates, and products were characterized by Fourier transform infrared spectroscopy(FTIR) and nuclear magnetic resonance(~1 H-NMR). GSE existed as a potential bio-based reactive diluent for petroleum-based epoxy resin. The curing kinetics of EP/HHPA/GSE system was studied by non-isothermal DSC method. The kinetics parameters were calculated by using the Kissinger model, Crane model, Ozawa model, and β-T(temperature-heating rate) extrapolation, respectively. In addition, the effects of GSE on the thermo-mechanical properties and thermal stability of EP/HHPA/GSE systems were studied, indicating that GSE can effectively improve the toughness and thermal decomposition temperature of the epoxy system.

丁香酚和月桂酸单甘油酯纳米乳对肉鸡生长性能、抗氧化能力和肠道健康的影响

本试验旨在研究在饮水中添加丁香酚(EUG)和月桂酸单甘油酯(GML)纳米乳对肉鸡生长性能、抗氧化能力和肠道健康的影响。选择1日龄、平均体重为(39.15±0.11)g的白羽肉鸡600只,随机分成5组,每组6个重复,每个重复20只。各组均饲喂基础饲粮,其中对照组正常饮水,试验组分别在饮水中添加0.5、1.0、3.0、5.0 mL/L的EUG和GML纳米乳。试验期42 d。结果表明:1)与对照组相比,饮水中添加1.0和3.0 mL/L的EUG和GML纳米乳显著提高了21、42日龄体重及1~21日龄、22~42日龄、1~42日龄平均日增重(P<0.05),显著降低了22~42日龄、1~42日龄料重比(P<0.05)。2)与对照组相比,饮水中添加1.0和3.0 mL/L的EUG和GML纳米乳显著提高了血清总抗氧化能力和谷胱甘肽过氧化物酶活性(P<0.05),显著降低了血清丙二醛含量(P<0.05);饮水中添加3.0 mL/L的EUG和GML纳米乳显著提高了血清超氧化物歧化酶活性(P<0.05)。3)与对照组相比,饮水中添加1.0、3.0和5.0 mL/L的EUG和GML纳米乳显著提高了十二指肠和空肠绒毛高度(P<0.05),显著降低了十二指肠隐窝深度(P<0.05);饮水中添加1.0和3.0 mL/L的EUG和GML纳米乳显著提高了十二指肠和空肠绒毛高度/隐窝深度(P<0.05)。4)与对照组相比,饮水中添加3.0和5.0 mL/L的EUG和GML纳米乳显著降低十二指肠和空肠肿瘤坏死因子-α和白细胞介素-1β基因相对表达量(P<0.05),饮水中添加1.0和3.0 mL/L的EUG和GML纳米乳显著提高了十二指肠和空肠白细胞介素-10基因相对表达量(P<0.05)。5)各组的盲肠菌群ACE、Chao1、Shannon和Simpson指数无显著差异(P>0.05)。与对照组相比,饮水中添加3.0 mL/L的EUG和GML纳米乳提高了盲肠拟杆菌门相对丰度,降低了厚壁菌门相对丰度。由此可见,饮水中添加EUG与GML纳米乳可增强肉鸡抗氧化能力,改善肉鸡肠道形态、炎症反应和菌群结构,提高肉鸡生长性能。在本试验中,饮水中EUG和GML纳米乳的适宜添加水平为3.0 mL/L。