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51.
广西产湿地松松针挥发性成分的提取及分析 总被引:4,自引:1,他引:3
采用水蒸气蒸馏法提取湿地松针叶挥发油的油相部分,用乙醚萃取法提取蒸馏残液中的水溶性挥发性组分,利用气相色谱-质谱联用分析比较二者的化学成分。湿地松挥发油油相部分的得油率为0.277%,共分离出86个色谱峰,鉴定了其中的49种化合物,占总含量的92.12%,油相部分的主要成分有β-蒎烯(14.29%)、吉马烯(12.87%)、α-蒎烯(6.79%)、β-石竹烯(6.15%)、α-石竹烯(1.58%);水溶性部分的得油率为0.0682%,鉴定了其中的6种化合物,占水溶性部分总量的60.72%,α-松油醇(24.61%)为水溶性部分的主要成分。由于增加了水溶部分精油的提取,湿地松松针挥发油总的产油率提高到0.3452%,提高率达24.62%。 相似文献
52.
采用固相微萃取(SPME)技术,结合气相色谱/质谱(GC-MS)分析了火炬松枝条和针叶中的挥发性化合物,共鉴定了30种化学成分。其中枝条中分离鉴定出21种挥发性成分。主要成分为α-蒎烯、β-蒎烯、β-月蒎烯、反式-石竹烯、β-杜松烯、大根叶烯-D;针叶中分离鉴定出24种挥发性成分,主要成分为α-蒎烯、β-蒎烯、β-月桂烯、β-水芹烯、异长叶烯、反式-石竹烯、α-律草烯、大根叶烯-D、双环吉马烯和双环榄香烯。 相似文献
53.
AnalysisoftheVolatileConstituentsofPinusTabulaeformisCarr.PineConesZHANGWei-huaandHOUDong-yan(DepartmentofChemislry,AnshanNor... 相似文献
54.
Julien Gabaston Ccile Leborgne Pierre Waffo‐Tguo Eric Pedrot Tristan Richard Jean‐Michel Mrillon Josep Valls Fonayet 《Journal of separation science》2020,43(6):1080-1088
Pine knots are a rich source of lignans, flavonoids, and stilbenes. These bioactive compounds are widely known for their roles to combat human disorders but also to protect plants against pathogens. In order to gain knowledge inside their potential activities, a suitable isolation and purification of these high‐added value compounds is required. To this end, centrifugal partition chromatography, as a rapid and useful methodology of separation, was employed and developed. The coefficient partition values (KD) of six major compounds in nine biphasic solvent systems were determined to evaluate the most appropriate system. Two‐step centrifugal partition chromatography was required to separate lignans using ARIZONA system K (n‐heptane/ethyl acetate/methanol/water 1:2:1:2, v:v) and to isolate stilbenes and flavonoids using ARIZONA system P (n‐heptane/ethyl acetate/methanol/water 6:5:6:5, v:v). Eight one‐compound enriched‐fractions were obtained as follows: nortrachelogenin (70.1%), secoisolariciresinol (53.7%), isolariciresinol (61.1%), taxifolin (48.4%), pinocembrin (91.3%), pinobanksin (91.1%), pinosylvin (91.4%), and pinosylvin monomethyl ether (91.1%). Additionally, the centrifugal partition chromatography allowed to unravel the composition of pine knot owing to the several fractions generated. Twenty‐two compounds were characterized by liquid chromatography‐mass spectrometry and NMR spectroscopy, some of which are described for the first time in literature. 相似文献
55.
Nguyen Hoang Sa Nguyen Thanh Tam Nguyen Thi Hoang Anh Tran Duc Quan Dao Duc Thien Dinh Thi Phong 《Natural product research》2018,32(3):341-345
A phytochemical study of n-hexane and ethyl acetate extracts of Pinus dalatensis Ferré leaves led to the isolation of 11 compounds, including one caryolane sesquiterpenoid (1), five labdane diterpenoids (2, 3, 4, 5, 6), one serratane triterpenoid (7), one diacylated flavonoid glucoside (8), one stilbenoid (9) and two sterols (10, 11). The structural characterisation of the isolated compounds was elucidated by spectroscopic data and comparison with the literature report on the chemical constituents from Pinus dalatensis Ferré. Futhermore, three compounds 1, 4 and 6 were obtained for the first time from the genus Pinus. Besides, compounds (2, 3, 5, 8, 9) were also subjected to cytotoxicity effect on SK-LU-1, MCF-7 and Hep-G2 cell lines, but only compound 9 expressed activities with IC50 values of 141.22, 127.81 and 166.84 μM, respectively. 相似文献
56.
57.
The fire retarding performance of 28 different inorganic chemical substances was tested by measuring the relative particle fire hazard properties of Pinus halepensis needles treated with these chemicals. The tests were performed using a new method, based on a specifically designed apparatus for monitoring the forest species temperature, under precisely controlled temperature and static air atmosphere conditions. The relative ignition and smoldering combustion properties determined were: the ignition delay time, the combustion rate, the heat content and the mass residue of forest samples. The key elements for the effectiveness of fire retardants were the delay of ignition and the reduction of heat and combustion rate. The chemicals examined were: Cu, Fe, Al2O3, Fe2O3, SiO2·H2O, NaHCO3, KI, KBr, KCl, NaCl, CaCO3, MnSO4·5H2O, CuSO4·5H2O, MgCl2·6H2O, Na2B4O7·10H2O, Na2HPO4, Na2CO3, Na2SiO3, ZnSO4·7H2O, Zn3(PO4)2·2H2O, NH4Br, NH4Cl, NH4HCO3, (NH4)2CO3, NH4H2PO4 (MAP), (NH4)2SO4 (AS), (NH4)2HPO4 (DAP) and a commercial retardant containing both DAP and AS. Among them the best performance was exhibited by ammoniac phosphates, followed by ammoniac sulfates and silica. 相似文献
58.
Sahar Ben Youssef Job Tchoumtchoua Maria Halabalaki Noureddine Allouche 《Journal of carbohydrate chemistry》2016,35(4):224-237
The use of precipitation followed by acetylation procedures and preparative TLC purification allowed a facile isolation of four carbohydrates from the methanol extract of Pinus halepensis seeds. The isolated oligosaccharides exhibited high degree of purity. They were identified as α-D-galactosyl-(1→1)-myo-inositol nonaacetate (1), α-D-glucosyl-(1→2)-β-D-fructosyl octaacetate (2), α-D-galactosyl-(1→6)-α-D-glucosyl-(1→2)-β-D-frutosyl undecaacetate (3), and α-D-galactosyl-(1→6)-α-D-galactosyl-(1→6)-α-D-glucosyl-(1→2)-β-D-frutosyl tetradecaacetate (4) and were isolated for the first time from this plant. The 1H and 13C NMR assignments for compounds 2, 3, and 4 were detailed herein for the first time. 相似文献
59.
Tahar Mekhalif Khalil Guediri Abdelbaki Reffas Derradji Chebli Abdeltif Amrane 《Journal of Dispersion Science and Technology》2017,38(4):463-471
The removal of methyl green (MG) dye from aqueous solutions using acid- or alkali-treated Pinus brutia cones (PBH and PBN) waste was investigated in this work. Adsorption removal of MG was conducted at natural pH, namely, 4.5 ± 0.10 for PBH and near 4.8 ± 0.10 for PBN. The pseudo-second-order model appeared to be the most appropriate to describe the adsorption process of MG on both PBN and PBH with a correlation coefficient R2 > 0.999. Among the tested isotherm models, the Langmuir isotherm was found to be the most relevant to describe MG sorption onto modified P. brutia cones with a correlation factor R2 > 0.999. The ionic strength (presence of other ions: Cl?, Na+, and SO42?) also influences the adsorption due to the change in the surface properties; it had a negative impact on the adsorption of MG on these two supports. A reduction of 68.5% of the adsorption capacity for an equilibrium dye concentration Ce of 30 mg/L was found for the PBH; while with PBN no significant influence of the ionic strength on adsorption was observed, especially in the presence of NaCl for dye concentrations superior to 120 mg L?1. 相似文献
60.
A new abietatrienoid, 15‐methoxydidehydroabietic acid ( 1 ), a new ring B‐seco abietatrienoid, 10‐hydroxy‐9,10‐secoabieta‐8,11,13‐trien‐18‐oic acid ( 2 ), and a new tetracyclic triterpenoid, pinusyunnanol ( 3 ), together with five known compounds, were obtained from the twigs and needles of Pinus yunnanensis. The structures of the new compounds were elucidated by means of extensive spectroscopic analyses. 相似文献