Residual dynamics of thiacloprid in medical herbs marjoram,thyme,and camomile in soil

Thiacloprid is a new insecticide of the chloronicotinyl family. To assess its risk after application, residual characteristics of thiacloprid in marjoram, thyme, and camomile and in soil were studied under field conditions. The active ingredient was extracted from the plant material using a mixture of acetone-water. After filtration, the extract was concentrated to the aqueous phase, diluted with water, and portioned against ethyl acetate on a matrix solid phase dispersion column. Thiacloprid was extracted from soil using a mixture of methanol-water, filtered, and re.extracted （clean up） with dichloromethane. The residues were quantified using HPLC-MS-MS. The methods were validated by recovery experiments. Thiacloprid residues in marjoram, thyme, and camomile and in soil persisted beyond 10, 14, 14, and 21 d but no residues were detected after 14, 21, 21, and 28 d, respectively. The data obtained in this study indicated that the biexponential model is more suitable than the first-order function to describe the decline of thiacloprid in fresh marjoram, fresh thyme, and dried camomile flowers with half-life （t1/2） of 1.1, 0.7, and 1.2 d, respectively. However, both the first-order function and biexponential model were found to be applicable for dissipation of thiacloprid in soil with almost the same t1/2 values of 3.5 and 3.6 d. The results indicated that thiacloprid dissipates rapidly and does not accumulate in the tested herbs and in soil.

Control of Tetranychus urticae Koch by extracts of three essential oils of chamomile,marjoram and Eucalyptus

Objective:To evaluate the acaricidal activity of extracts of three essential oils of chamomile,marjoram and Eucalyptwi against Tetranychus urtiaie(T.urticae.)Koch.Methods:Extracts of three essential oils of chamomile,marjoram and Eucalyptus with different concentrations(0.5%,1.0%,2.0%,3.0%and 4.0%)were used to control T.urticae Koch.Results:The results showed that chamomile(Chamomilla recutita)represented the most potent efficient acaricidal agent against Tetranychus followed by marjoram(Marjorana hortensis)and Eucalyptus.The LC_(50)values of chamomile,marjoram and Eucalyptus for adults were 0.65,1.84 and 2.18,respectively and for eggs 1.17,6.26 and 7.33,respectively.Activities of enzymes including glutathione-Stxansferase,esterase(α-esterase andβ-esterase)and alkaline phosphatase in susceptible mites were determined and activities of enzymes involved in the resistance of acaricides were proved.Protease enzyme was significantly decreased at LC_(50)of both chamomile and marjoram compared with positive control.Gas chromatography-mass spectrometer(CC-MS)proved that the major compositions of Chamomilla recutita areα-bisabolol oxide A(35.251%),and trans-3-farersene(7.758%),while the main components of Marjorana hortensis are terpincne-4-ol(23.860%),p-cymene(23.404%)and sabinene(10.904%).Conclusions:It can be concluded that extracts of three essential oils of chamomile,marjoram and Eucalyptus possess acaricidal activity against T.urticae.

Heat-denatured and alcalase-hydrolyzed protein films/coatings containing marjoram essential oil and thyme extract

In this study,heat-denatured and alcalase-hydrolyzed whey and soy protein films/coatings containing marjoram essential oil(MEO)and thyme extract(TE)were investigated comparatively in terms of physicochemical and functional properties.Heat-denaturated high protein solutions produced self-standing,smooth,transparent and viscoelastic films in the presence of glycerol.Enzymatic hydrolysis provided transparency,elasticity and extensibility to the films of low protein solutions.The addition of MEO and TE triggered hardness and brittleness especially in hydrolyzed high protein films and remarkably changed film color,thickness and viscosity possibly affecting surface adherence of films.Heat denatured films exhibited higher water vapor permeability(WVP)than alcalase-hydrolyzed ones.The lowest hardness was obtained in hydrolyzed low protein films with considerable adhesiveness.Hydrolyzed protein solutions coated to cheese provided better protection against moisture loss and MEO added films caused elevated hardening of cheese.MEO and TE incorporated in film matrices were seemed to suppress mycelial growth and sporulation of Aspergillus niger.This study presented valuable new findings on functional protein films produced by enzymatic hydrolysis as an alternative to heat treatment.

Effect of Rosmarinus officinalis and Origanum majorana extracts on stability of sunflower oil during storage and repeated heating

Both rosemary(Rosmarinus officinalis)and marjoram(Origanum majorana)are abundant in phenolic compounds,exhibiting exceptional antioxidant activity.This study aims to assess the impact of rosemary and marjoram extracts on the stability of sunflower oil during storage and repeated heating.Sunflower oil supplemented with herbal extracts or butylated hydroxytoluene(BHA)at a concentration of 200 ppm was stored for six months under light and dark conditions at room temperature.Peroxide value(PV),p-anisidine value(An-V),and total oxidation(TOTOX)value were measured to monitor lipid oxidation progression.A significant difference(P<0.05)was observed between light and dark storage for all studied samples regarding oxidation parameters.The ethanolic extract of rosemary exhibited higher antioxidant activity compared to BHA and other extracts.Furthermore,sunflower oil supplemented with the ethanolic extract of rosemary underwent weekly treatment at 100℃for 30 min over four consecutive weeks.Although all oxidation indicators increased during repeated heating,the addition of rosemary and marjoram extracts as well as BHA significantly reduced these indicators.These findings demonstrate that both rosemary extracts and marjoram extracts can serve as natural antioxidants in edible oils.

迷迭香精油和马郁兰精油化学成分及抗氧化活性研究

采用气相色谱与质谱联用(GC-MS)的方法分析了迷迭香精油和马郁兰精油的化学成分,研究两种精油的抗氧化活性。从迷迭香精油和马郁兰精油中分别鉴定出75,80种化学成分,其中共有化合物25种。迷迭香精油的主要化学成分有樟脑(22.72%)、桉叶油醇(17.66%)、α-蒎烯(16.11%)、莰烯(9.87%)、2-茨醇(4.59%)等。马郁兰精油中主要成分有4-萜烯醇(25.13%)、4-侧柏醇(16.93%)、γ-萜品烯(10.36%)、(+)-4-蒈烯(6.50%)、桧烯(5.06%)等,两种精油在化学组成和含量上有较大差异。两种精油均具有一定的抗氧化活性,但马郁兰精油的抗氧化活性优于迷迭香精油。

马郁兰精油对大鼠力竭游泳导致的运动性疲劳不具有改善作用

目的探究马郁兰精油是否具有减轻运动性疲劳的作用及其机制。方法雄性SD大鼠随机分为负重强迫游泳组(WL-FST)和负重强迫游泳+马郁兰精油处理组(WL-FST+MEO),并进行2周负重游泳训练。马郁兰精油通过雾化方式吸入,剂量为4μL/h。测量大鼠血压、心率(HR)、抓力、力竭时间、行为学和心肌细胞线粒体形态,并测定力竭游泳后血清中葡萄糖(GLU)、游离脂肪酸(FFA)、肌酸激酶(CK)和乳酸脱氢酶(LDH)的水平。结果与WL-FST组相比,WL-FST+MEO组大鼠舒张压和HR下降(P<0.05,P<0.01)、力竭时间缩短(P<0.01),而抓力和收缩压无显著差异(P>0.05)。旷场实验表明WL-FST+MEO组大鼠中央区域移动距离和滞留时间显著低于WL-FST组(P<0.05)。两组大鼠血清GLU、FFA、CK和LDH活力之间无显著性差异(P>0.05)。与WL-FST组相比,WL-FST+MEO组大鼠心肌细胞线粒体中出现嵴间隙增宽、断裂或溶解呈空泡状的表征更明显。结论实验结果提示,马郁兰精油不能改善大鼠力竭游泳导致的运动性疲劳。马郁兰精油可降低运动性疲劳大鼠的血压和HR,但对运动导致的疲劳大鼠焦虑样行为和心肌损伤无改善作用。

GC/MS法分析甘牛至油中香味成分

利用GC/MS对甘牛至油中香味成分进行了分析,并用峰面积归一化法计算各成分相对含量,通过质谱库检索,保留指数比对,分析并确定了58个化合物,占甘牛至油香味成分95.61%,采用保留指数来鉴别同系物及同分异构体,提高了对甘牛至油中成分定性的准确性。通过香气分析,确定了甘牛至油中关键致香成分分别为芳樟醇、α-松油醇、1,8-桉叶素、乙酸芳樟酯、α-蒎烯、β-蒎烯、月桂烯、莰烯、β-石竹烯、桧烯、樟脑、龙脑等,为甘牛至油产品开发和应用提供了理论依据。

马郁兰提取物联合抗阻运动对心肌梗塞大鼠心肌的保护作用

马郁兰(Origanum majorana L.)是一种有香味的多年生草本植物,可以作为烹饪中的调味剂,也具有抗炎、抗氧化等药用价值。最新研究显示,马郁兰提取物(Origanum majorana extract,OME)对心肌梗死具有预防作用。本研究旨在探讨马郁兰提取物(OME)结合抗阻运动(RE)对心肌梗死大鼠心肌I/R损伤的影响。实验分为Sham组、MI组、RE组、L-OME组、M-OME组、H-OME组和RE+H-OME组。研究结果显示,OME结合RE能显著减少心肌梗死面积、改善心肌形态,并减轻心肌氧化应激和炎症。此外,该组合干预还能显著降低TUNEL阳性心肌细胞比率,减少心肌细胞凋亡。分子水平上,OME结合RE能够显著提高心肌中Notch1和Hes1的表达。这些结果表明,OME联合RE可作为一种潜在的治疗策略,通过激活Notch1/Hes1通路减轻心肌梗死后的心肌I/R损伤。本研究为心肌梗死后的心肌保护提供了新的研究视角,并为未来临床研究奠定了基础。