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71.
The effect of rootstock (‘MaxMa 14’, ‘Weiroot 13’, ‘PiKu 1’, ‘Weiroot 158’, ‘Gisela 5’ and ‘F12/1’) on phenolic acid and flavonol content of “Lapins” sweet cherry was investigated. Phenolic acids and flavonols were isolated from sweet cherries and analyzed by using reversed phase high-performance liquid chromatography (RP-HPLC). The major phenolic acids in sweet cherries were neochlorogenic acid (18–50 mg kg−1), chlorogenic acid (19–62 mg kg−1) and p-coumaric acid derivatives (15–125 mg kg−1). The amount of flavonol quercetin-3-rutinoside (8–37 mg kg−1) was significant as well. There are significant variations in the phenolic compound content among sweet cherry fruits grown on trees grafted on different vegetative rootstocks. The significantly higher chlorogenic acid, neochlorogenic acid, p-coumaric derivative and quercetin-3-rutinoside contents were found in sweet cherry fruits grown on trees grafted on ‘Weiroot 13’ and ‘PiKu 1’ rootstocks. Sweet cherries produced on trees grafted on other rootstocks had significantly lower phenolic compound content.  相似文献   
72.
微藻油脂制备生物基多元醇理化性能分析与结构表征   总被引:2,自引:2,他引:0  
为了实现有效高值利用非食用、不占耕地的绿色可再生油脂资源,该研究以微藻油脂为原料,采用环氧化-开环法和氢甲酰化-加氢还原法制备了2种生物基多元醇,通过主要理化指标碘值、酸值、环氧基含量、羟值的测定,重要理论理化指标理论双键含量、理论环氧基含量、理论羟值、转化率和选择性的计算,结合气质联用、凝胶渗透色谱、红外光谱、核磁共振等仪器分析手段,对原料和产物的理化性能和结构进行分析与表征。结果表明,微藻油脂的主要脂肪酸是油酸,质量分数为91.10%,碘值为88.46 g/100 g,理论双键含量0.34 mol/100 g,环氧-开环法得到的多元醇碘值降至0.62 g/100 g,羟值为150.35 mg/g,原料转化率和目标产物选择性分别为99.30%和86.74%,结构中引入仲羟基,通过及时除去环氧反应过程中生成的水、开环反应选择适宜的醇用量可提升产品质量。氢甲酰化-加氢还原法得到的多元醇碘值降至2.12 g/100 g,羟值为166.29 mg/g,原料转化率和目标产物选择性分别为97.60%和95.83%,结构中引入伯羟基,该法为非均相反应,催化剂过滤可除,副反应少,溶剂廉价可回收,产品易分离且质量容易控制。2种方法的原料利用率都很高,目标产物选择性好,产品性能可通过简单易行的理化指标测定和理论计算方法进行有效评价,并可利用仪器分析手段快速监测反应进程、保证产品质量、查找质量问题、拓宽应用范围,具有很好的经济性和工业应用前景,研究结果为油脂为原料的生物基多元醇深入研究和工业应用提供了科学可靠的数据基础和技术支持。  相似文献   
73.
Plant growth regulators such as α?naphthylacetic acid (NAA) or 6?benzyladenine (BA) are commonly used for thinning apple fruits. NAs exhibits an auxin- and gibberellin-type biological activity, stimulate the uptake and translocation of auxins in plant tissue, as well as IAA synthesis and act as surfactants. It was assumed that NAs applied at the stadium of early fruit growth might cause fruit abscission in apple, similarly to NAA. The goal of the research was to test the presumed thinning effect of naphthenic acids on apple cultivars ‘Golden Delicious’ and ‘Red Delicious’. Three treatments were applied on both apple cultivars including 16.5?μL L?1 NAA, 200?μL L?1?BA and 2.63?mg L?1?potassium salts of NAs. Cortical cell size and the number of cell layers were measured in order to determine the contribution of cell size and cell division in early fruit growth, as affected by chemical thinning treatments. The effects of plant growth regulators NAA, BA and NAs on fruit set, fruit size and the anatomy of the fruit cortex highly depend on varietal differences. In ‘Golden Delicious’ fruit set reduction by chemical thinning increases both the number of cell layers and cell size of apple fruit, while in ‘Red Delicious’ NAA inhibits fruit growth, while BA is ineffective. Cell growth promoting activity of NAA and NAs, accompanied by the decrease in fruit set and reduced competition among fruits within the canopy, results in a significant fruit weight increase at harvest. The research confirms the auxinic properties of NAs, and their assumed thinning activity.  相似文献   
74.
Increasing the amount of n‐3 PUFA in carp meat is one of the most important tasks in enhancing its overall quality. However, the relative influence of supplemental feed and natural feed on the FA profile of cultivated carp flesh is not well documented, making it difficult to choose the most efficient strategy. Carp diet composition and diet and flesh fatty acid profiles were simultaneously followed in order to determine the influence of pelleted feed compared to natural feed on fatty acid profiles of carp tissues. Pelleted feed clearly dominated over zooplankton and Chironomidae in the carp diet, producing carp tissue fatty acid profiles closely resembling those of pelleted feed. However, increase in the abundance of zooplankton over the course of the investigation resulting in concomitant increase of its proportion in feed bulk was in strong positive correlation with increase in n‐3 HUFA in the dorsal muscle. n‐3 PUFA enrichment of supplemental feed could be the dominant mechanism in production of carp meat rich in n‐3 PUFA. However, even a small increase in natural feed availability could significantly change the diet of common carp and result in considerable improvement of meat quality with regard to n‐3 HUFA content.  相似文献   
75.
We used the eddy-covariance technique to measure evapotranspiration (E) and gross primary production (GPP) in a chronosequence of three coastal Douglas-fir (Pseudotsuga menziesii) stands (7, 19 and 58 years old in 2007, hereafter referred to as HDF00, HDF88 and DF49, respectively) since 1998. Here, we focus on the controls on canopy conductance (gc), E, GPP and water use efficiency (WUE) and the effect of interannual climate variability at the intermediate-aged stand (DF49) and then analyze the effects of stand age following clearcut harvesting on these characteristics. Daytime dry-foliage Priestley–Taylor α and gc at DF49 were 0.4–0.8 and 2–6 mm s?1, respectively, and were linearly correlated (R2 = 0.65). Low values of α and gc at DF49 as well at the other two stands suggested stomatal limitation to transpiration. Monthly E, however, showed strong positive linear correlations to monthly net radiation (R2 = 0.94), air temperature (R2 = 0.77), and daytime vapour pressure deficit (R2 = 0.76). During July–September, monthly E (mm) was linearly correlated to monthly mean soil water content (θ, m3 m?3) in the 0–60 cm layer (E = 453θ ? 21, R2 = 0.69), and GPP was similarly affected. Annual E and GPP of DF49 for the period 1998–2007 varied from 370 to 430 mm and from 1950 to 2390 g C m?2, respectively. After clearcut harvesting, E dropped to about 70% of that for DF49 while ecosystem evapotranspiration was fully recovered when stand age was ~12 years. This contrasted to GPP, which varied hyperbolically with stand age. Monthly GPP showed a strong positive linear relationship with E irrespective of the stand age. While annual WUE of HDF00 and HDF88 varied with age from 0.5 to 4.1 g C m?2 kg?1 and from 2.8 to 4.4 g C m?2 kg?1, respectively, it was quite conservative at ~5.3 g C m?2 kg?1 for DF49. N-fertilization had little first-year response on E and WUE. This study not only provides important results for a more detailed validation of process-based models but also helps in predicting the influences of climate change and forest management on water vapour and CO2 fluxes in Douglas-fir forests.  相似文献   
76.
Tilapia wild spawning is a nuisance in warm freshwater aquaculture growout ponds. To cope with this problem two experiments were carried out with predatory fish that do not reproduce in fresh water. One experiment tested the capacity of hybrid bass (Morone saxatilis × M. chrysops) and red-drum (Sciaenops ocellatus) as predators of wild spawning of hybrid tilapia (Oreochromis niloticus × O.aureus), and the other compared predation effectiveness of red-drum of different sizes and stocking densities.Both hybrid bass and red-drum effectively reduced tilapia wild spawning and improved by 15–20% tilapia performance and food conversion ratio. These effects were obtained stocking small red-drum (20 g) or large red-drum (60–80 g) or bass (135 g) at stocking densities of 500–1000 predators/ha, together with 15000 tilapia/ha of 65–75 g. Hybrid bass stocked at 750/ha and large red-drum stocked at 500/ha presented over 90% survival. Red-drum at higher stocking density and/or lower stocking weight presented reduced survival (40–60%). Red-drum of all examined stocking weights presented better growth rates when stocked at 500/ha than at higher densities.  相似文献   
77.
Chitosan microparticulate delivery systems containing clotrimazole were prepared by a spray drying technique using glycerol 2-phosphate as an ion cross-linker. The impact of a cross-linking ratio on microparticle characteristics was evaluated. Drug-free and drug-loaded unmodified or ion cross-linked chitosan microparticles were examined for the in vitro cytotoxicity in VK2/E6E7 human vaginal epithelial cells. The presence of glycerol 2-phosphate influenced drug loading and encapsulation efficacy in chitosan microparticles. By increasing the cross-linking ratio, the microparticles with lower diameter, moisture content and smoother surface were observed. Mucoadhesive studies displayed that all formulations possessed mucoadhesive properties. The in vitro release profile of clotrimazole was found to alter considerably by changing the glycerol 2-phosphate/chitosan ratio. Results from cytotoxicity studies showed occurrence of apoptotic cells in the presence of chitosan and ion cross-linked chitosan microparticles, followed by a loss of membrane potential suggesting that cell death might go through the mitochondrial apoptotic pathway.  相似文献   
78.
Vitrification was applied to the sperm of two endangered fish species of So?a River basin in Slovenia, the Adriatic grayling (Thymallus thymallus) and marble trout (Salmo marmoratus) following testing different cooling devices and vitrifying media. Sperm was collected, diluted in species-specific non-activating media containing cryoprotectants, and vitrified by plunging directly into liquid nitrogen without pre-cooling. Progressive motility, curvilinear velocity, and straightness of fresh and vitrified-warmed sperm were evaluated with computer-assisted sperm analysis (CASA). Fertilization trials were carried out to test the effectiveness of vitrification in the case of grayling. A protocol utilizing a glucose-based extender, 30% cryoprotectants (15% methanol + 15% propylene glycol), 1:1 dilution ratio, and droplets of 2 μl on a Cryotop as cooling device yielded the highest post-thaw motility values for both Adriatic grayling (7.5?±?6.5%) and marble trout (26.6?±?15.8%). Viable embryos were produced by fertilizing eggs with vitrified grayling sperm (hatching 13.1?±?11.7%, control hatching 73.9?±?10.4%). The vitrification protocol developed in this study can be utilized in the conservation efforts for the two species as an alternative to slow-rate freezing when working in field conditions or when specific equipment necessary for slow-rate freezing is not available.  相似文献   
79.
Plant Foods for Human Nutrition - Satureja kitaibelii Wierzb. ex Heuff. has a great importance in Serbian ethnopharmacology/herbal traditional medicine, as well as a flavoring food additive....  相似文献   
80.
The aim of this study was to examine the influence of dyeing on antibacterial efficiency of corona activated polyamide and polyester fabrics loaded with colloidal Ag nanoparticles as well as the influence of the presence of Ag nanoparticles on the color change of dyed fabrics. C.I. Acid Green 25 and C.I. Disperse Blue 3 were used for dyeing of polyamide fabrics and C.I. disperse violet 8 for polyester fabrics. The color change of polyamide fabrics depends on the dye type, which was generally lower compared to polyester fabrics. Antibacterial efficiency of Ag loaded fabrics was tested against Gram-positive bacterium Staphylococcus aureus and Gram-negative bacterium Escherichia coli. Corona activated polyester and polyamide fabrics showed excellent antibacterial efficiency independently of order of dyeing and Ag loading. The morphology of fibers loaded with Ag nanoparticles was assessed by SEM and atomic absorption spectroscopy for elemental analysis.  相似文献   
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