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1.
The concentrations of myricetin in medicinal plants such as Rosa canina L. (rosa hip), Terebinthina chica L. (terebinth), Urtica dioica L. (nettle), and Portuca oleracea L. (purslane) were determined by high-performance liquid chromatography-mass spectrometry (HPLC-MS). The aglycones of myricetin were extracted using methanol–ascorbic acid– hydrochloric acid, methanol–hydrochloric acid, and methanol, separated within 5 min, and individually quantitated in the positive ionization mode using optimized conditions for HPLC-MS. Methanol–ascorbic acid–hydrochloric acid was the optimum extraction solvent. The myricetin concentration in the plants were between 3 and 58 mg kg?1, with a limit of quantification equal to 0.1 mg L?1.  相似文献   
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The objectives of the present study were to investigate anthocyanin profiles and their biological properties, including antioxidant, anticancer, and antiallergic, from the red petals of Korean edible rose (Rosa hybrida cv. Noblered). The acidic methanol extract of this species showed potent biological activities at a concentration of 50 μg/mL. Its anthocyanins were characterised as cyanidin 3,5-di-O-glucoside and pelargonidin 3,5-di-O-glucoside using reversed-phase C18 column chromatography, NMR spectroscopy, and HPLC-DAD-ESI/MS analysis. Cyanidin 3,5-di-O-glucoside was the predominant constituent (375 mg/100 g), representing about 85% of total content. Cyanidin 3,5-di-O-glucoside exhibited good scavenging activity against DPPH radical with IC50 value of 55.2 μg/mL; pelargonidin 3,5-di-O-glucoside showed potent anticancer effects against LNCap (human prostate cell line), ACHN (human renal cell line) and MOLT-4F (human leukaemia cell line) cell cultures, with IC50 values of 6.43, 18.3, and 6.78 μg/mL, respectively. Antiallergic activities were only moderate.  相似文献   
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以金樱子果为原料,经过酒精发酵和醋酸发酵生产保健醋饮料.运用正交实验确定醋酸发酵的工艺条件为:醋酸菌接种量为15%,初始酒精度7%,发酵温度33℃,发酵时间为5d.  相似文献   
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Due to the increasing interest in certain components, specially the oil, from non-conventional seeds as Rosa mosqueta (Rosa rubiginosa) and Chilean hazelnut (Gevuina avellana), quick determinations of oil and other parameters were carried out by using near-infrared (NIR) spectroscopy. Moisture, oil, fiber (as acid detergent fiber) and protein from solid samples of the seeds as mentioned, along with those of soybean (Glycine max), already analyzed by NIR and for serving as control for the variability of the method, were studied. Sample interactions to NIR radiations were processed using the multivariate regression algorithm Partial Least Squared (PLS) to build a calibration model. Standard error of cross-validation (SECV) was used to estimate the prediction error. Moisture of Rosa mosqueta, Chilean hazelnut presscake and soybean meal (in the ranges 10–15, 10–15, 8–10%, respectively), acid detergent fiber (60–68, 12–16, 10–15%, respectively), oil (1–4, 14–20, 5–13%, respectively) and protein (1–5, 8–15, 27–45%, respectively) were previously determined by wet analysis using standard methods, so creating a library. The possibility to analyze parameters from very different oilseeds with an acceptable uncertainty was also established. Standard errors of cross-validation were between 1.25 and 2.99%, being the oil content the best predicted parameter.  相似文献   
6.
The composition, functional properties and structural features of the fiber from Rosa rubiginosa defatted seeds and from Gevuina avellana defatted and partially deproteinized seeds were evaluated. The effect of phosphate salts and temperature during the extraction of fibres and the influence of two drying technologies on the distribution of soluble and insoluble dietary fibre were assessed. The extraction of protein and monosaccharides was favoured by increasing temperature in the range studied. Water and oil absorption capacities higher than 10 g g?1 were observed for soluble and insoluble fibres from Gevuina avellana and for the soluble ones from Rosa rubiginosa. The insoluble fibre product from Rosa and Gevuina contained 650–810 g kg?1 and 390–440 g kg?1 neutral detergent fibre respectively. The protein content in the insoluble fibre varied in the range 100–150 g kg?1 and 120–260 g kg?1 and in the soluble fibre between 200–550 g kg?1 and 180–370 g kg?1 for Rosa and Gevuina respectively. Copyright © 2004 Society of Chemical Industry  相似文献   
7.
探索不同辅助方法对刺玫果总多酚提取率的影响。通过单因素和正交试验获得传统溶剂法提取刺玫果总多酚的最佳工艺条件为:料液比1:50(g:mL)、提取溶剂为50%的乙醇溶液、提取温度80℃、提取1.5h,总多酚提取率为11.28mg/g;然后分别考察离子液体辅助、离子液体协同超声波辅助、离子液体协同超声波-微波辅助对刺玫果总多酚提取率的影响。试验结果表明,经离子液体氯化-1-丁基-3-甲基咪唑辅助提取后刺玫果总多酚的提取率较传统溶剂法提高了14.98%;经离子液体协同超声波辅助提取后刺玫果总多酚提取率提高了16.13%;经离子液体协同超声波-微波辅助提取后刺玫果总多酚提取率提高了20.66%。上述结果表明,离子液体辅助、离子液体协同超声波辅助、离子液体协同超声波-微波辅助均能提高刺玫果总多酚的提取率,为刺玫果总多酚的后续开发利用提供了试验参考。  相似文献   
8.
BACKGROUND: Mechanization of Rosa damascena flower harvest is limited because of the asynchronous flowering period, the necessity for the harvest operation to take place in the early hour of the morning, and a lack of knowledge regarding the physical–mechanical properties of R. damascena. This study investigated the effect of harvesting hour on some physical–mechanical properties of R. damascena. RESULTS: The terminal velocity of the rose flower ranged from 4.00 to 2.38 m s?1. The highest picking force was found to be 6.29 N for the harvesting hour of 06:00 am. Tear forces of petal changed from 1.54 to 0.97 N for the harvesting hour of 06:00 am and 12:00 pm, respectively. The tension force of pedicel varied between 8.25 and 7.76 N. The weight of the rose flower was measured as an average of 1.61 and 1.50 g at 06:00 am and 12:00 pm, respectively. Horizontal and vertical projection areas of rose flowers were positively correlated with harvesting hour, with an R2 of 0.97 and 0.75, respectively. Results showed that there was a minor loss in colour for both inner and outer surfaces of petals. CONCLUSION: The results of physical–mechanical properties of R. damascena obtained from this study should be considered for the operation of flower harvest mechanization. Copyright © 2011 Society of Chemical Industry  相似文献   
9.
Rosa laxa Retz., a shrub belonging to the family Rosaceae, is widely distributed in the northern foothills of the Tianshan Mountains in Xinjiang, China. The fruits of R. laxa (FRL) has antibacterial, hypolipidemic, and antioxidant effects. In this study, FRL was subjected to pharmacognostic identification of its source, morphology, microscopic characteristics, and physicochemical properties. The microscope showed that the cross-sectional features of FRL were obvious, and the FRL powder contained vessel, parenchyma cells, exocarp cells, pollen grains, and cluster crystals. Scanning electron microscopy (SEM) analysis results show that numerous villi and many small particles (particle size of 5–50 μm) were observed in the FRL powder, and there are many gullies on the surface of the particles. In addition, the secondary metabolites of FRL were characterized via ultraviolet–visible (UV–Vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and thin-layer chromatography (TLC). Results showed that FRL contains various secondary metabolites, including flavonoids, phenolic acids, glycosides, and tannins. Water as the extraction solvent had the highest extraction rate and the contented of total flavonoids was 2.88 mg/g, and the contented of total polyphenols was 54.89 mg/g. Moreover, TLC identification revealed that it contains catechin and tiliroside. These parameters of FRL, which are reported herein, are important to the development of the pharmacognostic standards, as well as in the identification and quality control of FRL.  相似文献   
10.
目的 优化超声辅助水提醇沉法提取刺梨多糖的工艺条件, 探究不同产地与品种间的刺梨多糖含量及抗氧化活性差异。方法 以提取率为指标, 在单因素试验基础上, 通过正交试验对超声辅助水提醇沉法工艺条件进行优化; 并以该工艺对毕节地区不同产地与品种的刺梨样品进行多糖含量的测定与分析, 对1,1-二苯基-2-苦基肼(1,1-diphenyl-2-picrylhydrazyl, DPPH)自由基和2,2’-联氨-双(3-乙基苯并噻唑啉-6-磺酸)二胺盐[2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, ABTS]阳离子自由基清除能力进行测定, 比较各样品多糖的抗氧化活性。结果 超声辅助水提醇沉法提取刺梨多糖的最优工艺为: 提取温度75℃, 提取时间2.5 h, 料液比1:60 (g/mL); 其最佳提取率为11.88%。对37个产地的3个品种间多糖含量分析可知, 野生品种的多糖含量整体更高, 为40.87%, 纳雍县的多糖含量整体最高, 为41.40%, 刺梨多糖含量与海拔高度间未见规律性变化。各刺梨多糖对DPPH·的半抑制浓度(half maximal inhibitory concentration, IC50)明显小于对ABTS+·的IC50, 抗氧化活性未见与海拔高度存在直接相关。结论 优化后的超声辅助水提醇沉提取工艺高效可行, 各产地间多种刺梨品种多糖含量的高低呈现出一定的品种倾向性与区域偏向性, 其多糖抗氧化活性也存在较大的差异, 这可为刺梨在地区间的精准栽培及选种育种提供参考, 为刺梨资源在功能食品开发等方面提供技术和理论支持。  相似文献   
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