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1.
《Plant Production Science》2013,16(5):497-508
Abstract

Doubled haploid lines (DHLs) of rice (Oryza sativa L.) were used to examine responses to drought and rewatering in controlled rainfed lowland conditions, in order to determine whether confounding by unrelated traits would be less than has been reported previously for contrasting cultivars that differ in genetic background. IR62266 and four DHLs derived from the cross between IR62266 and CT9993 (DHL-32, -51, -54 and -79) were grown in pot experiments in the greenhouse during the 2000 dry and wet seasons at IRRI, Los Baños, Philippines. There were two water regimes (well-watered and drought). Estimated water extraction obtained by time domain reflectometry (TDR) was similar to cumulative transpiration estimated from pot weighing for each genotype. Genotypic variation was observed in root traits and water extraction, with extraction slower in DHL-32 and faster in DHL-79, especially in deeper soil layers. An upper bound relationship between water extraction from a soil layer and root length density (RLD) in that layer was readily apparent over DHLs and soil depths, suggesting a critical value of RLD for water extraction of 0.30 cm cm?3 in these conditions. Because soils in the field would not be as homogenous as the puddled soils used in these greenhouse experiments, this critical RLD for water extraction from a soil layer is a reference for ideal conditions, and requires careful validation in the field. Use of DHLs permitted comparisons with reduced confounding by genetic background, with consequent improvements in precision.  相似文献   

2.
Plant Foods for Human Nutrition - A simple and efficient ultrasonic-assisted extraction (UAE) technique was developed in order to find optimal conditions for the extraction of total phenolic...  相似文献   

3.
Polyunsaturated fatty acids are well known for their protective properties in relation to different skin diseases. Although seaweeds possess a low lipid fraction, they could act as an alternative renewable source of polyunsaturated fatty acids whenever other valuable seaweed components are also valorized. In this study, a biorefinery process using Mastocarpus stellatus as a model seaweed was proposed. The process started with the supercritical carbon dioxide extraction of the lipid and phenolic fractions. The influence of pressure during extraction with pure supercritical CO2 was studied while operating at a selected temperature and solvent flow rate. Kinetic data obtained during the ethanol-modified supercritical CO2 extraction were fitted to the spline model. Sequential processing was proposed with (i) pure CO2 to obtain a product with 30% PUFA content and ω-3:ω-6 ratio 1:1, (ii) ethanol-modified CO2 to extract phenolics, and (iii) microwave-assisted subcritical water extraction operating under previously optimized conditions for the extraction of phenolics, carrageenan and protein fractions. The composition of the supercritical extracts showed potential for use in both dietary and topical applications in skin care products. The remaining solids are suitable for the extraction of other valuable fractions.  相似文献   

4.
Plant Foods for Human Nutrition - Conventional techniques for phenolics extraction from pomegranate (Punica granatum) peel (PP) have several insufficiencies like longer time duration, bioactive...  相似文献   

5.
为了揭示草本纤维提取菌种资源类型以及其与生态环境的关系,作者对不同生态环境下的草本纤维提取菌种进行了资源多样性及其生境研究。结果显示:(1)菌种资源多样性与分离基质有较大关系,土壤和水体是草本纤维提取菌种的理想生境,从土壤或水体中能分离出大部分类型的草本纤维提取菌种,而从腐殖质、厩肥中能分离出某些特殊功能的草本纤维提取菌种;(2)菌种资源多样性与地域关系不是很大,不同地域都表现出了较好的多样性,多样性指数在1.2-2.2之间;(3)群落相似性在0.2-0.7之间,大部分属于中等不相似。  相似文献   

6.
The effects of three independent variables: solvent polarity, temperature and extraction time on the antioxidant capacity, total phenolic content and phenolic acid composition in extracts obtained from sunflower shells before and after enzymatic treatment were studied. Response surface methodology based on three-level, three-variable Box-Behnken design was used for optimization of extraction parameters and evaluation of their effect on antioxidant capacity and total phenolic content in shell extracts.The average antioxidant capacities of extracts from sunflower shells without enzymatic treatment (368.1-1574.4 μmol TE/100 g) were higher than those for cellulolytic and pectolytic enzymes-treated shells (222.7-1419.0 and 270.7-1570.7 μmol TE/100 g, respectively). The content of total phenolic compounds ranged between 58.2-341.2 mg CGA/100 g, 26.7-277.3 mg CGA/100 g and 51.4-301.5 mg CGA/100 g for extracts obtained from shells without enzyme and treated with cellulolytic and pectolytic enzymes, respectively. Total phenolic content (TPC) in the studied shell extracts correlated significantly (p < 0.0001) positively with their antioxidant capacity determined by the ferric reducing antioxidant power (FRAP) method (r = 0.9275). Results of FRAP, TPC and phenolic acid composition in the studied shell extracts depend on the extraction conditions (solvent polarity, temperature, time), but they are independent on the addition of enzyme solutions. The antioxidant capacity and total phenolic content in the resulting extracts increased with a line in extraction temperature and solvent polarity.  相似文献   

7.
基因组DNA的提取是DNA分子水平研究和检测的重要环节.为补充完善现场检测方法,根据硅膜吸附DNA的特性,结合过滤膜和注射器,开发一种现场快速提取植物基因组DNA的方法.选取大豆、棉花、油菜、玉米、水稻5种主要作物的叶片和种子为样品提取DNA,利用PCR和普通重组酶聚合酶扩增(recombinase polymeras...  相似文献   

8.
槟榔叶片总蛋白质提取及双向电泳条件初探   总被引:4,自引:1,他引:3  
采用3种提取植物组织蛋白的方法(TCA/丙酮沉淀法、E-TCA法、酚法)提取槟榔叶片总蛋白,在蛋白产量,一维和二维电泳图谱等方面对3种方法的提取效果进行比较.结果表明,TCA/丙酮沉淀法效果较好,是槟榔叶片总蛋白提取的可选方法,同时优化了双向电泳的条件和上样量.  相似文献   

9.
超声波辅助提取大豆总木脂素及其含量分析   总被引:1,自引:0,他引:1  
以乙醇为浸提溶剂,超声波辅助提取不同品种大豆中的木脂素,并用紫外-可见分光光度法对其含量进行分析,同时对浸提溶剂、料液比、浸提时间及次数等因素进行比较。结果表明:以乙醇为浸提溶剂,料液比在1/8~1/12范围,浸提时间20 min,浸提2次效果比较理想;标准对照品在0~0.18 mg.mL-1浓度范围内吸光度与其总木脂素含量呈良好的线性关系,回归方程A=6.081c+0.0445,相关系数r=0.9998,总木脂素检出限8.3×10-5mg.mL-1,平均回收率为94.4%,RSD为1.2%。该方法简便、实用、可靠,可对大豆木脂素的深入研究提供参考。  相似文献   

10.
The chestnut bur, a forest waste product from chestnut processing in the food industry, was studied as a potential source of natural antioxidants. Extractions were performed using aqueous solutions of methanol or ethanol. Experiments were planned according to an incomplete 33 factorial design to study the influence of temperature (25-75 °C), time (30-120 min) and solvent concentration (50-90%) on extraction yield and on extract properties: total phenols content, antioxidant activity (using the FRAP, DPPH and ABTS methods) and average molecular weights. All dependent variables were influenced by temperature and solvent concentration whereas the influence of time was almost negligible. Using the response surface methodology the optimal extraction conditions were selected: the highest temperature assayed (75 °C), the lowest solvent concentration (50%) and an extraction time of 75 min for the methanolic extractions and of 30 min for the ethanolic ones. Under those conditions the values predicted for extraction yield and total phenols content were 18.95% and 36.32 g GAE/100 g extract for the methanolic extract and 17.95% and 26.11 g GAE/100 g extract for the ethanolic ones. Methanolic extracts showed superior total phenols content and antioxidant properties and slightly higher extraction yields than ethanolic extracts; however, ethanol is recommended for food applications due to its GRAS (Generally Recognized as Safe) qualification. Gallic acid esters of glucose, ellagic acid and small proportions of quercetin-3-β-d-glucoside, phenolic compounds with demonstrated antioxidant properties, were identified in chestnut bur extracts by RP-HPLC-ESI-TOF.  相似文献   

11.
Long chain phenols contained in cashew nut shell liquid (CNSL) are found to have important pharmaceutical applications, such as antitumor, antimicrobial, urease inhibitory and lipoxygenase activities, and also are well known in coating and resin industry. The impact of different extraction methods on CNSL yield, selectivity towards preferable compounds, composition and characteristic of extracts was investigated. Four different methods employed in extracting CNSL from CNS were: supercritical carbon dioxide (SC-CO2) extraction (40 °C, 300 bar, 4 h), subcritical water (SCW) extraction (140 °C, 22 bar, 1 h), soxhlet extraction (solvent boiling point, atmospheric pressure, 30 h), and two-step extraction, which comprises a solvent extraction followed by a SCW extraction. Characteristic of the extracts differed significantly. Methanol and two-step extraction resulted in darker and more turbid extracts, while n-hexane and SC-CO2 extracts were clearer and lighter in color. GC-FID/MS chromatograms showed differences in compositions of the extracts obtained by different methods. Two-step extraction yielded extracts that contain 81.17-82.98% total long chain phenols (around 50% based on dry CNS) with monounsaturated cardanol as the major compound, producing higher amount of total phenols than other methods. SCW extraction showed high selectivity towards monounsaturated cardanol and stigmasterol, while high concentration of monounsaturated anacardic acid and cardol appeared in SC-CO2 extract.  相似文献   

12.
The extracted dye from brown dry rind of the pomegranate has been used as natural colorant for textiles from ancient times. In this study, microwave assisted extraction (MAE) has been used for extraction for dye from dried pomegranate rind. The effect of three independent parameters namely extraction time (25–90 s), pH of solution (3.5–8) and amount of pomegranate rind (0.5–1.5 g) was considered. Response surface methodology (RSM) is applied to optimize the effects of processing parameters of extraction on the yield of dye and a computer-stimulated artificial neural network (ANN) model is developed to get a good correlation between the input variables responsible for extraction and the output parameter (concentration of dye) of extraction from pomegranate rind. Considering the yield of dye extraction and the feasibility of the experiment, the optimum conditions of dye extraction are extraction time 90 s, pH 3.5, amount of sample 1.48. Application of microwave irradiation method proved to be a rapid and improved technique for dye extraction and significantly reduced the extraction time. The optimization procedure shows a close interaction between the experimental and simulated values for dye extraction.  相似文献   

13.
Ale MT  Mikkelsen JD  Meyer AS 《Marine drugs》2011,9(10):2106-2130
Seaweeds--or marine macroalgae--notably brown seaweeds in the class Phaeophyceae, contain fucoidan. Fucoidan designates a group of certain fucose-containing sulfated polysaccharides (FCSPs) that have a backbone built of (1→3)-linked α-L-fucopyranosyl or of alternating (1→3)- and (1→4)-linked α-L-fucopyranosyl residues, but also include sulfated galactofucans with backbones built of (1→6)-β-D-galacto- and/or (1→2)-β-D-mannopyranosyl units with fucose or fuco-oligosaccharide branching, and/or glucuronic acid, xylose or glucose substitutions. These FCSPs offer several potentially beneficial bioactive functions for humans. The bioactive properties may vary depending on the source of seaweed, the compositional and structural traits, the content (charge density), distribution, and bonding of the sulfate substitutions, and the purity of the FCSP product. The preservation of the structural integrity of the FCSP molecules essentially depends on the extraction methodology which has a crucial, but partly overlooked, significance for obtaining the relevant structural features required for specific biological activities and for elucidating structure-function relations. The aim of this review is to provide information on the most recent developments in the chemistry of fucoidan/FCSPs emphasizing the significance of different extraction techniques for the structural composition and biological activity with particular focus on sulfate groups.  相似文献   

14.
An efficient and good DNA extraction protocol should be simple, affordable and yield enough DNA with high quality. Rice(Oryza sativa L.) DNA extraction methods often use seedlings or leaves rather than the grains and tend to be time-consuming, involve multiple steps, and use hazardous chemicals and expensive enzymes. Rice grains offer several benefits over seedlings and leaves as a source of DNA for genetic analysis. However, these benefits are underutilized because the bulk of a rice grain is made up of starch. It is particularly important, but difficult to get rid of the starch while extracting DNA from rice grains. This co-precipitated polysaccharide is a known inhibitor of DNA polymerase activity in polymerase chain reaction(PCR). We describe here a very simple and highly affordable Chelex~?-100 based DNA extraction method from rice grains. It does not require any hazardous chemicals or enzymes. This method reproducibly extracts DNA with good purity indices(A_(260)/A_(230) and A_(260)/A_(280) values), but requires only a few steps.  相似文献   

15.
Plant Foods for Human Nutrition - In this paper, high-hydrostatic pressure extraction (HHPE) as an emerging food processing and preservation technique constitutes an alternative to conventional...  相似文献   

16.
萌发期大豆总蛋白提取及双向电泳体系的优化   总被引:1,自引:0,他引:1  
蛋白质样品的制备和双向电泳条件是蛋白组学研究中很关键同时也是很棘手的问题。本文比较了TCA/丙酮法、酚抽提、苯酚/SDS法3种不同的蛋白提取方法,并对双向电泳的一些条件进行了优化,建立了适合萌发期大豆总蛋白的双向电泳体系,即采用17cm、p H4-7的IPG胶条,凝胶浓度为12%,蛋白质上样量为0.2mg。IEF程序为:250V 1h,500V 1h,3 000V 3h,8 000V 1h,10 000V 1h,10 000V 60 000Vh。本研究为萌发期大豆的蛋白组学研究提供了实验方法。  相似文献   

17.
This study aims to explore novel extraction technologies (ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), ultrasound–microwave-assisted extraction (UMAE), hydrothermal-assisted extraction (HAE) and high-pressure-assisted extraction (HPAE)) and extraction time post-treatment (0 and 24 h) for the recovery of phytochemicals and associated antioxidant properties from Fucus vesiculosus and Pelvetia canaliculata. When using fixed extraction conditions (solvent: 50% ethanol; extraction time: 10 min; algae/solvent ratio: 1/10) for all the novel technologies, UAE generated extracts with the highest phytochemical contents from both macroalgae. The highest yields of compounds extracted from F. vesiculosus using UAE were: total phenolic content (445.0 ± 4.6 mg gallic acid equivalents/g), total phlorotannin content (362.9 ± 3.7 mg phloroglucinol equivalents/g), total flavonoid content (286.3 ± 7.8 mg quercetin equivalents/g) and total tannin content (189.1 ± 4.4 mg catechin equivalents/g). In the case of the antioxidant activities, the highest DPPH activities were achieved by UAE and UMAE from both macroalgae, while no clear pattern was recorded in the case of FRAP activities. The highest DPPH scavenging activities (112.5 ± 0.7 mg trolox equivalents/g) and FRAP activities (284.8 ± 2.2 mg trolox equivalents/g) were achieved from F. vesiculosus. Following the extraction treatment, an additional storage post-extraction (24 h) did not improve the yields of phytochemicals or antioxidant properties of the extracts.  相似文献   

18.
Nannochloropsis oceanica can accumulate lipids and is a good source of polar lipids, which are emerging as new value-added compounds with high commercial value for the food, nutraceutical, and pharmaceutical industries. Some applications may limit the extraction solvents, such as food applications that require safe food-grade solvents, such as ethanol. However, the effect of using ethanol as an extraction solvent on the quality of the extracted polar lipidome, compared to other more traditional methods, is not yet well established. In this study, the polar lipid profile of N. oceanica extracts was obtained using different solvents, including chloroform/methanol (CM), dichloromethane/methanol (DM), dichloromethane/ethanol (DE), and ethanol (E), and evaluated by modern lipidomic methods using LC-MS/MS. Ultrasonic bath (E + USB)- and ultrasonic probe (E + USP)-assisted methodologies were implemented to increase the lipid extraction yields using ethanol. The polar lipid signature and antioxidant activity of DM, E + USB, and E + USP resemble conventional CM, demonstrating a similar extraction efficiency, while the DE and ethanol extracts were significantly different. Our results showed the impact of different extraction solvents in the polar lipid composition of the final extracts and demonstrated the feasibility of E + USB and E + USP as safe and food-grade sources of polar lipids, with the potential for high-added-value biotechnological applications.  相似文献   

19.
荔枝果皮精油的超临界萃取研究及精油成分分析   总被引:9,自引:0,他引:9  
荔枝果皮精油的超临界CO2萃取研究及精油成分分析的实验结果表明,荔枝果皮粉精油的最佳萃取条件为: 12 MPa,35℃, 1~1.5 h,当含水量为 6%时萃出率较高。采用气相色谱-质谱联用技术进行精油成分分析,鉴别出60多种成分。  相似文献   

20.
Two approaches were investigated in attempts to obtain a high extraction yield of (glucurono) arabinoxylans from water-unextractable cell wall material (WUS) of wheat bran using saturated barium hydroxide containing 0·26 M sodium borohydride. First, the effect of three pretreatments (autoclave treatment, alkaline peroxide and chlorite delignification) of the WUS prior to extraction appeared to have no effect on the extraction yield. Moreover, modifications to the composition and molecular weight distribution of the (glucurono)arabinoxylans occurred when such treatments were used. Second, the effect of an increasing extraction temperature and concentration of alkali was investigated. Increasing the extraction temperature improved the extraction yield of (glucurono)arabinoxylans from 29% at 20°C to 50% at 95°C. Increasing the barium hydroxide concentration with the temperature resulted in no further improvements in extraction yield up to 70°C. Above this temperature the extraction yield decreased. Substitution of barium hydroxide by calcium hydroxide resulted in lower yields and a lower selectivity; the lower solubility of calcium hydroxide may have been responsible for this. Supplementary experiments to investigate the mechanism of the selectivity of the bivalent hydroxide extraction with addition of sodium borohydride indicated a possible role for borate, derived from borohydride.  相似文献   

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