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1.
Hydrolates obtained via the hydrodistillation and steam distillation of Lavandula angustifolia Mill., Syzygium aromaticum L., Foeniculum vulgare Mill., and Laurus nobilis L. were analyzed by gas chromatography with flame ionization detector (GC-FID) and gas chromatography coupled to mass spectrometry (GC-MS). Additionally, the hydrolates were evaluated for antimicrobial activity (disk-diffusion and microdilution method), influence on biofilm formation (Christensen method) and cytotoxicity of concentrated hydrolates against human cell lines (A549) by xCELLigence system. Using chemical analysis, 48, 9, 13 and 33 different components were detected in lavender, clove, fennel and laurel hydrolates, respectively. Lavender hydrolate contained the largest proportion of 1,8-cineol, linalool furanoxide, and linalool. The main components of laurel hydrolate were 1,8-cineol, 4-terpineol and α-terpineol. Fenchone and estragole were the most abundant in fennel hydrolate, and eugenol and eugenyl acetate in clove hydrolate. Concentrated hydrolates showed significant antimicrobial activity. Clove hydrolate was among the most antimicrobially active agents, most preferably against C. albicans, with an inhibition zone up to 23.5 mm. Moreover, concentrated hydrolates did not show any cytotoxic effect again8 st human A549 cells. In the presence of the non-concentrated hydrolates, significantly reduced biofilm formation was observed; however, with concentrated clove hydrolate, there was an increase in biofilm formation, e.g., of A. thereius, A. lanthieri, and A. butzleri. Research shows new findings about hydrolates that may be important in natural medicine or for preservation purposes.  相似文献   
2.
In Iran and other parts of Western Asia, the oleaster (Elaeagnus angustifolia L.) fruit is processed in the dried powdery form, and in recent times, increasingly applied/sprinkled in fruit juices such as those made from oranges (Citrus sinensis L.). To our best knowledge, the effectiveness of oleaster fruit extract in fortifying the orange juice has not yet been reported and the knowledge of this will greatly benefit the consumers, particularly those around the Western Asia region. This current work, therefore, investigated the changes in physicochemical, free radical activity, total phenolic compounds, and sensory properties of orange juice fortified with different oleaster fruit extracts. The orange juice mix formulation comprised different concentrations (5, 10, 15, 20, and 25%) of oleaster (alcoholic, aqueous, and hydro-alcoholic) extracts. The control comprised orange concentrate (4% w/v), sugar (8.5% w/v), and citric acid (0.1% w/v) brought to the desirable volume with water. As the free radical activity depicted the antioxidant properties, the physicochemical aspects of this work involved the determinations of Brix, density, ash, pH, total acidity, sucrose, and total sugar, whereas the sensory aspects involved the determinations of color and taste. Whilst the aqueous oleaster 20 and 25% extracts produced notable physicochemical differences in the orange juice mix, both free radical activity, and phenolic compounds significantly increased (p < 0.05) after 30 days despite resembling (p > 0.05) those of control at day 1. More so, the increases in aqueous, alcoholic, and hydro-alcoholic oleaster extracts would decrease (p < 0.05) the sensory color and taste of the orange juice mix in this study.  相似文献   
3.
内蒙古地区沙生植物--沙枣对亚硝酸盐分解作用的研究   总被引:2,自引:0,他引:2  
利用分光光度法研究了内蒙古地区沙生植物———沙枣对亚硝酸盐的分解作用。结果表明,沙枣中富含的维生素C、维生素E和脯氨酸等抗氧化剂可以作为还原剂与亚硝酸盐作用,从而降低亚硝酸盐的含量;加入的沙枣量愈多,随时间延长对亚硝酸盐的分解能力亦增强,但不呈线性关系。试验结果表明,沙枣不仅可以作水土保持、防沙造林的先锋树种,还由于它富含抗氧化物,可作为人体降低体内亚硝胺生成的良好补充源。  相似文献   
4.
Two new ent-kaurene diterpenoids, angustifolin B and natural hydrogen-bonded 1:1 complex, angustifolin C, as well as four known diterpenoids, angustifolin, isodonal, sodoponin, tri-chorabdal B, were isolated from the leaves of Rabdosia angustifolia.  相似文献   
5.
The characterization of the effects of different sizes and loadings of Typha latifolia on the tensile, thermal, and morphological properties of linear-low-density polyethylene (LLDPE)/T. latifolia composites were evaluated using tensile test, Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy analyses. Results indicated the tensile strength and elongation at break decreased as T. latifolia loading increased. However, T. latifolia fine size (fs) exhibited better tensile properties than coarse size at the same loading in the composite. T. latifolia (15%, fs) recorded higher thermal stability than LLDPE control and other T. latifolia loadings and sizes due to the strong interaction of T. latifolia (15%, fs) in LLDPE matrix as shown in morphology.  相似文献   
6.
In the present work, a two-dimensional qNMR method for the determination of sennosides was established. Using band-selective HSQC and the cross correlations of the characteristic 10–10’ bonds, we quantified the total amount of the value-determining dianthranoids in five minutes, thus, rendering the method not only fast, but also specific and stability indicating. The validation of the method revealed excellent accuracy (recovery rates of 98.5 to 103%), precision (RSD values of 3.1%), and repeatability (2.2%) and demonstrated the potential of 2D qNMR in the quality control of medicinal plants. In a second method, the use of 2D qNMR for the single analysis of sennosides A, B, and A1 was evaluated with acceptable measurement times (31 min), accuracy (93.8%), and repeatability (5.4% and 5.6%) for the two major purgatives sennoside A and B. However, the precision for sennoside B and A1 was not satisfactory, mainly due to the low resolution of the HSQC signals of the two compounds.  相似文献   
7.
Abstract

The pollen of T. angustifolia, also known as Pu huang in Chinese, has been used for treatment of stranguria, hematuria, dysmenorrhea, metrorrhagia and injuries in China for a long time. Extensive efforts have been directed toward its phytochemical and biological aspects. However, little is known about its anti-nociceptive implication and material basis. This work presented the investigation of the anti-nociceptive effect of Typhae Pollen using an effect-directed fractionation strategy, thereby leading to identification of isorhamnetin-3-O-neohesperidin (1) and typhaneoside (2), together with other minor flavonoid glycoside congeners, as the main anti-nociceptive constituents. This work not only unveils the anti-nociceptive potential of Typhae Pollen, but also establishes a method to enrich and identify the anti-nociceptive constitutes of Typhae Pollen. Moreover, this work is a successful example of effect-directed fractionation strategy, which represents a powerful tool in TCM-based drug discovery and development.  相似文献   
8.
沙枣(Elaeagnus angustufolia L.)又名香柳、桂香柳,属胡颓子科胡颓子属的乔木,具有抗旱,耐盐碱,抗风沙的特性,分布于我国  相似文献   
9.
Seeds of Echinacea angustifolia are known for their deep dormancy. In this paper, we studied the responses of E. angustifolia seeds to some chemical and physical factors, such as scarification, chilling (5 °C) period, light and applied BA (6-benzylaminopurine), GA3 (gibberellic acid) and sound stimulation. When the seed coat layers were removed, the germination rate grew up from 6 to 20% (incubated in light) and the mean time germination (MTG) was reduced from 18 to 6.6 days. On the basis of layers-removed, chilling and continuous light gave significantly higher germination rate (up to 70%). Compare the data of seeds chilled by 0, 6, 12, 18 and 24 days, the maximum germination rate (up to 70%) achieved at 18-days chilling treatment. Further increases in the chilling period could slightly improve germination. Exogenous application of 0.1, 0.2, 0.3 mg/L GA3 or BA in the previous pretreatment increased germination to 78, 90 and 84% or 76, 86 and 84%, respectively. Obviously, the best concentration of GA or BA is 0.3 mg/L. And the GA3 or BA treatment shortened the MTG to about 4 days. The influence of sound stimulation was also tested in the experiment. The result showed that one 100 dB and 1000 Hz sound wave (sine-wave) was beneficial to the germination of E. angustifolia seeds.  相似文献   
10.
It was shown that the method for obtaining hydrolates from lavender (Lavandula angustifolia) influences the content of active compounds and the aromatic, antimicrobial and antioxidant properties of the hydrolates. The content of volatile organic compounds ranged from 9.12 to 97.23 mg/100 mL of hydrolate. Lavender hydrolate variants showed low antimicrobial activity (from 0% to 0.05%). The radical scavenging activity of DPPH was from 3.6 ± 0.5% to 3.8 ± 0.6% and oxygen radical absorbance capacity (ORACFL) results were from 0 to 266 μM Trolox equivalent, depending on the hydrolate variant.  相似文献   
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