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Summary The aim of this investigation was to obtain qualitative and quantitative profiles of the flavonoid and biflavonoid composition
of six cypress species—Cupressus funebris L.,Cupressus sempervirens L.,Cupressus glabra L.,Cupressus arizonica L.,Cupressus goveniana L., andCupressus lusitanica L. HPLC-diode-array detection (DAD), HPLC-MS, and HPTLC were used to identify the individual compounds. A chromatographic
method was optimized for identification and quantification of the main flavonoid glycosides and biflavonoids. The flavonoids
identified and calibrated were: rutin, quercetin glucoside, quercetin rhamnoside, and kaempferol 3-O-rhamnoside. The biflavonoids identified and calibrated were: cupressuflavone, amentoflavone, robustaflavone, hinokiflavone,
methylrobustaflavone, methylamentoflavone, and dimethylcupressuflavone. 相似文献
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苹果叶片不定芽的高频诱导及植株再生的研究 总被引:6,自引:0,他引:6
体外建立并扩繁了苹果品种“乔纳金”、“新世界”、“王林”,“北斗”的无性系,在MS附加BA0.5 ̄2.0mg/L、IBA0.1 ̄0.5mg/L的培养基中,2个月内芽的数量可增至5倍,在MS培养基附加BA5.0mg/L IAA0.2mg/L的下,4个品种的叶片再生率可达90%以上,其中以“乔纳金”最高,可达100%,当TDZ为3mg/L,IAA0.2为0.5mg/L时,其再生频率明显高于BA。 相似文献
5.
A new extraction method for ginsenosides from ginseng roots, ginseng leaves and ginseng drug preparations by Sep-Pak C18 cartridges has been studied. Ginsenoside extraction by Sep-Pak cartridges is a rapid, efficient, reproducible method. In addition, the extracts were analyzed by high performance thin layer chromatography (HPTLC) and reverse phase high performance liquid chromatography (HPLC). The major components of ginseng saponins were effectively separated using an ODS-120T column. 相似文献
6.
Four myrosinase (β-thioglucosidase EC. 3.2.3.1) and seven disaccharase (β-fructofuranosidase, EC. 3.2.1.26) isoenzymes were isolated from turnip leaves. The most active enzymes were isolated in pure
form. Myrosinase and disaccharase mol wt was 62.0 × 103 and 69.5 × 103 dalton, respectively, on the basis of gel filtration on Sephadex G-200.
Myrosinase pH profile showed high activity between pH 5 and 7 with the optimum at pH 5.5. The purified enzyme was heat-stable
for 60 min at 30°C with only loss of 24% of activity. Its activity is strongly inhibited (100%) by Pb2+, Ba2+, Cu2+ and Ca2+ ions, and activated (70%) by EDTA at 0.04M. The pure enzyme failed to hydrolyze amylose, glycogen, lactose, maltose, and
sucrose. TheK
m andV
max values of myrosinase using sinigrin as specific substrate was 0.045 mM and 2.5 U, respectively.
The maximal activity of disaccharase enzyme was obtained at pH 4–5 and 35–37°C. The enzyme was heat-stable at 30°C for 30
min with only 10% loss of its activity. Its activity is strongly activated (70–240%) by Ca2+, Ba2+, Cu2+, and EDTA at 0.01M. The enzyme activity is specific to the disaccharide sucrose and failed to hydrolyze other disaccharides (maltose and lactose).
TheK
m andV
max of disaccharase were 0.123 mM and 3.33 U, respectively. 相似文献
7.
Sansei Nishibe Kumiko Mitsui-Saitoh Junichi Sakai Takahiko Fujikawa 《Molecules (Basel, Switzerland)》2021,26(8)
Forsythia fruit (Forsythia suspensa Vahl (Oleaceae)) is a common component of Kampo medicines for treating the common cold, influenza, and allergies. The main polyphenolic compounds in the leaves of F. suspensa are pinoresinol β-d-glucoside, phillyrin and forsythiaside, and their levels are higher in the leaves of the plant than in the fruit. It is known that polyphenolic compounds stimulate lipid catabolism in the liver and suppress dyslipidemia, thereby attenuating diet-induced obesity and polyphenolic anti-oxidants might attenuate obesity in animals consuming high-fat diets. Recently, phillyrin was reported as a novel cyclic AMP phosphodiesterase 4 (PDE4) inhibitor derived from forsythia fruit. It was expected that the leaves of F. suspensa might display anti-obesity effects and serve as a health food material. In this review, we summarized our studies on the biological effects of forsythia leaves containing phillyrin and other polyphenolic compounds, particularly against obesity, atopic dermatitis, and influenza A virus infection, and its potential as a phytoestrogen. 相似文献
8.
《Arabian Journal of Chemistry》2022,15(4):103707
Alsophila spinulosa is a tree-like fern, and many evidences suggested that plant polyphenols had the potential therapeutic for Alzheimer s disease (AD). Herein, polyphenols (ASP) was isolated from A. spinulosa leaves and its major constituent were isoorientin and vitexin. ASP displayed excellent antioxidant activity and obvious anti-lipid peroxidation capacity in vitro. ASP improved the survival rate of C. elegans under high temperature by enhancing the antioxidant enzymes activities and decreasing the lipid peroxidation level. Moreover, ASP alleviated β-amyloid (Aβ) induced paralysis and reduced Aβ deposition, decreased reactive oxygen species (ROS) accumulation and improved the level of skn-1 mRNA. In addition, ASP decreased the levels of pdk-1 and akt-1 mRNA in P13K/AKT signaling pathway. In conclusion, ASP may be a potential ingredient for the alleviation of AD. 相似文献
9.
Forty one terpenoidal compounds were isolated from the essential oil of Chamaecyparis formosensis Matsum. The dominant component is α-pinene. Other major components include β-pinene, 3-carene, α-terpineol, γ-muurolene, and kaurene. 相似文献
10.
烟草中多酚氧化酶的生理生化特征及其活性控制的研究 总被引:29,自引:0,他引:29
对烟草叶中的多酚氧化酶(PPO)进行了部分纯化,对比了叶中PPO在苗期和田间的活性差异,研究了其活性变化规律,发现生长旺盛期PPO活性高于其他时期,研究了烟叶在不同水势条件下PPO活性变化规律,发现水势过高、过低,PPO活性均较低,在一872.78kPa水势条件下,PPO活性最高,所以细胞中的含水量是影响PPO活性的因素之一.研究了PPO在35℃、40℃、45℃、50℃、55℃、60℃、65℃、70℃和75℃等烘烤温度条件下的热敏感性,发现:酶的最适反应温度为35℃;温度由35℃升至75℃,活性逐渐下降,在每一温度下保持5min,活性趋于稳定,用回归法得出了烟叶中PPO的下降百分数与温度之间的关系式.用双倒数作图法比较了NaDiCa、EDTA、巯基乙醇和硫脲4种常用抑制剂对烟叶中PPO活性的抑制强度,结果表明:同一浓度下它们对PPO的抑制强度依次递减,而NaDiCa抑制效率明显高于其他3种抑制剂;CuCl2可以促进PPO活性,用回归法得出了活力增加百分数与二价铜离子浓度的关系式。 相似文献