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41.
Merieme Ledrhem Miku Nakamura Miyu Obitsu Kinue Hirae Jun Kameyama Hafida Bouamama Chemseddoha Gadhi Yoshinori Katakura 《Molecules (Basel, Switzerland)》2022,27(7)
Cistus L. is a genus of dicotyledonous perennial herbaceous plants. Cistus species have been commonly used in folk medicine in the Mediterranean region. In the present study, the biological activities of essential oils derived from Cistus species (Cistus laurifolius, C. monspeliensis, C. creticus, and C. salviifolius) were evaluated. Essential oils derived from C. laurifolius and C. monspeliensis were found to augment the expression of SIRT1, an anti-aging gene, in the normal culture of HaCaT cells. Furthermore, these essential oils increased the number and size of mitochondria and augmented their activity. These effects were thought to be caused by the up- and downregulated expression of MITOL and Drp1 in HaCaT cells, respectively, in response to the essential oil treatment. In addition, these essential oils were found to attenuate ultraviolet-B-induced mitochondrial damage and cellular senescence in HaCaT cells. These findings indicate that essential oils derived from C. laurifolius and C. monspeliensis may inhibit skin aging through mitochondrial regulation via SIRT1 activation. 相似文献
42.
Metakaolin-based geopolymer microspheres (MGM) with hierarchical pore structures were prepared by suspension dispersion method in dimethicone at 80 °C. The hydrothermal modification of MGM was carried out at a lower temperature of 80 °C, and a NaA molecular sieve converted from metakaolin-based geopolymer (NMGM) with good crystal structure was prepared and applied in thermal catalytic cracking of low-density polyethylene (LDPE) reaction. The one-pot two-stage thermal catalytic cracking of LDPE was carried out in a 100 mL micro-autoclave under normal pressure. In this work, the optimal proportions and optimal reaction conditions of catalysts for NMGM thermal catalytic cracking of LDPE waste to fuel oil were investigated. The NMGM catalyst showed high selectivity to the liquid product of thermal catalytic cracking of waste LDPE. Under the reaction conditions of reaction time of 1 h and reaction temperature of 400 °C, the liquid-phase yield of thermal catalytic cracking of LDPE reached a high of 88.45%, of which the content of gasoline components was 10.14% and the content of diesel components was 80.97%. 相似文献
43.
Ellen de Nazar S. da Cruz Luana de Sousa Peixoto Jamile S. da Costa Rosa Helena V. Mouro Walnice Maria O. do Nascimento Jos Guilherme S. Maia William N. Setzer Joyce Kelly da Silva Pablo Luis B. Figueiredo 《Molecules (Basel, Switzerland)》2022,27(8)
Eugenia patrisii Vahl is a native and non-endemic myrtaceous species of the Brazilian Amazon. Due to few botanical and phytochemical reports of this species, the objective of the present work was to evaluate the seasonal variability of their leaf essential oils, performed by GC and GC-MS and chemometric analysis. The results indicated that the variation in oil yields (0.7 ± 0.1%) could be correlated with climatic conditions and rainy (R) and dry seasons (D). (E)-caryophyllene (R = 17.1% ± 16.0, D = 20.2% ± 17.7) and caryophyllene oxide (R = 30.1% ± 18.4, D = 14.1% ± 19.3) are the major constituents and did not display significant differences between the two seasons. However, statistically, a potential correlation between the main constituents of E. patrisii essential oil and the climatic parameters is possible. It was observed that the higher temperature and insolation rates and the lower humidity rate, which are characteristics of the dry season, lead to an increase in the (E)-caryophyllene contents, while lower temperature and insolation and higher humidity, which occur in the rainy season, lead to an increase in the caryophyllene oxide content. The knowledge of variations in the E. patrisii essential oil composition could help choose the best plant chemical profile for medicinal purposes. 相似文献
44.
采用水蒸气蒸馏法提取姜味草挥发油,用气相色谱法-氢火焰离子化检测器测定挥发油中橙花醛和香叶醛的含量。橙花醛和香叶醛的线性范围分别为0.0971~0.5826g·L~(-1)和0.1152~0.6912g·L~(-1)方法用于测定4批次姜味草挥发油中橙花醛与香叶醛的含量,橙花醛与香叶醛的质量分数分别为25.00%,29.... 相似文献
45.
低温等离子体与MnO_x/γ-Al_2O_3协同催化降解正己醛 总被引:2,自引:0,他引:2
研究了在低温等离子体和催化剂共同作用下低浓度正己醛的降解反应.结果表明,等离子体与γ-Al2O3之间产生了很好的催化协同作用,在低放电功率(2.8W)和低温(80℃)下,干燥空气气氛中,γ-Al2O3对0.12%正己醛的去除率为87.1%;当γ-Al2O3负载7.5%MnOx后,正己醛去除率达到96.5%,其效果与Pt/γ-Al2O3相当.7.5%MnOx/γ-Al2O3在实验条件下连续使用50h,其催化活性未见下降. 相似文献
46.
47.
Supramolecular oleogel is a soft material with a three-dimensional structure, formed by the self-assembly of low-molecular-weight gelators in oils; it shows broad application prospects in the food industry, environmental protection, medicine, and other fields. Among all the gelators reported, amino-acid-based compounds have been widely used to form organogels and hydrogels because of their biocompatibility, biodegradation, and non-toxicity. In this study, four Nα, Nε-diacyl-l-lysine gelators (i.e., Nα, Nε-dioctanoyl-l-lysine; Nα, Nε-didecanoyl-l-lysine; Nα, Nε-dilauroyl-l-lysine; and Nα, Nε-dimyristoyl-l-lysine) were synthesized and applied to prepare oleogels in four kinds of vegetable oils. Gelation ability is affected not only by the structure of the gelators but also by the composition of the oils. The minimum gel concentration (MGC) increased with the increase in the acyl carbon-chain length of the gelators. The strongest gelation ability was displayed in olive oil for the same gelator. Rheological properties showed that the mechanical strength and thermal stability of the oleogels varied with the carbon-chain length of the gelators and the type of vegetable oil. The microstructure of oleogels is closely related to the carbon-chain length of gelators, regardless of oil type. The highest oil-binding capacity (OBC) was obtained in soybean oil for all four gelators, and Nα, Nε-dimyristoyl-l-lysine showed the best performance for entrapping oils. 相似文献
48.
Ibrahim Taha Radwan Mohamed M. Baz Hanem Khater Abdelfattah M. Selim 《Molecules (Basel, Switzerland)》2022,27(6)
(1) Background: The control of mosquitoes with essential oils is a growing demand. (2) Methods: This study evaluated the novel larvicidal and adulticidal activity of fennel and green tea oils and their nanostructured lipid carriers (NLC) against Culex pipiens (C. pipiens) in the laboratory, field conditions and evaluated their effect against non-target organisms. SLN type II nanoformulations were synthesized and characterized using dynamic light scattering (DLS), zeta potential and transmission electron microscope. (3) Results: The synthesized NLCs showed spherical shaped, homogenous, narrow, and monomodal particle size distribution. The mortality percent (MO%) post-treatment (PT) with 2000 ppm for 24 h with fennel oil and NLC fennel (NLC-F) reached 85% (LC50 = 643.81 ppm) and 100% (LC50 = 251.71), whereas MO% for green tea oil and NLC green tea (NLC-GT) were 80% (LC50 = 746.52 ppm) and 100% (LC50 = 278.63 ppm), respectively. Field trial data showed that the larval reduction percent of fennel oil and NLC-F reached 89.8% and 97.4%, 24 h PT and the reduction percent of green tea oil and NLC-GT reached 89% and 93%, 24 h PT with persistence reached 8 and 7 days, for NLC-F and NLC-GT, respectively. The adulticidal effects showed that NLC-F and NLC-GT (100% mortality) were more effective than fennel and green tea oils (90.0% and 83.33%), with 24 h PT, respectively. Moreover, their reduction of adult density after spraying with LC95 X2 for 15 min, with fennel oil, NLC-F, and green tea oil, NLC-GT were 83.6%, 100%, 79.1%, and 100%, respectively, with persistence (>50%) lasting for three days. The predation rate of the mosquitofish, Gambusia affinis, and the bug, Sphaerodema urinator, was not affected in both oil and its NLC, while the predation rate of the beetle, Cybister tripunctatus increased (66% and 68.3%) by green tea oil and NLC-GT, respectively. (4) Conclusions: NLCs nanoformulation encapsulated essential oils was prepared successfully with unique properties of size, morphology, and stability. In vitro larvicidal and adulticidal effects against C. pipiens supported with field evaluations have been performed using essential oils and their nanoformulations. The biological evaluation of nanoformulations manifested potential results toward both larvicidal and adulticidal compared to the essential oils themselves, especially NLC encapsulated fennel oil which had promising larvicidal and adulticidal activity. 相似文献
49.
胜利油田稠油组分的光谱法研究 总被引:1,自引:0,他引:1
用红外光谱, 紫外光谱及同步荧光光谱对胜利油田稠油中的沥青质和胶质进行了分析。红外光谱分析结果表明,胶质、沥青质分子含有可形成氢键的羟基、胺基、羧基、羰基等极性基团,说明原油中 胶质分子之间、沥青分子之间及二者相互之间有强烈的氢键作用,具有很强的极性。通过紫外吸收光谱及同步荧光光谱的测定,并与模型化合物的紫外吸收特征峰及荧光光谱的特征峰相比较,结果表明, 芳香单片是研究稠油中胶质、沥青质组分结构的最基本单位。单元芳香片中芳香环的个数以3~4个环为主,共轭芳香环的排列形式主要为“线性排列”,即渺位缩合。但胶质和沥青质的结构也存在着差异, 即胶质中主要含有3~4个环的共轭芳香片,而沥青质中含有少量多于5个环的共轭芳香片,并且这些共轭芳香片有部分“面性排列”,即迫位缩合。 相似文献
50.