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1.
红毛五加多糖的基本性质研究   总被引:4,自引:0,他引:4  
本文从红毛五加中分离得到了三种多糖,并对它们的基本性质进行了研究。红毛五加经热水浸提,用Sevag法脱蛋白,经DEAE-cellulcse 32离子交换层析和Sephacryl S-200HR凝胶层析纯化得到三个主要多糖组分:AHP-Ⅰ,AHP-Ⅱ和AHP-Ⅲ。HPLC测定AHP-Ⅰ、AHP-Ⅱ和AHP-Ⅲ的表观分子质量分别为7.0kD、59.5kD和12.9kD。红外光谱分析三种多糖具有多糖类物质的一般特征。经纸层析和GC结果综合分析得知,AHP-Ⅰ含有阿拉伯糖、岩藻糖、甘露糖、葡萄糖、半乳糖,其摩尔比为1.00:1.40:0.64:3.13:2.09;AHP-Ⅱ含有鼠李糖、阿拉伯糖、甘露糖、葡萄糖和半乳糖,其摩尔比为0.36:1.00:0.15:0.20:1.10;AHP-Ⅲ含有鼠李糖、阿拉伯糖、岩藻糖、甘露糖、葡萄糖和半乳糖,其摩尔比为1.22:1.00:0.40:0.28:0.26:1.03。咔唑-硫酸法测得AHP-Ⅱ、AHP-Ⅲ的糖醛酸含量分别为6.7%和6.0%;AHP-Ⅰ不含糖醛酸。体内试验表明,红毛五加粗多糖对小鼠S180肉瘤有明显抑制作用。  相似文献   

2.
为了研究木瓜多糖的提取、分离、纯化与抗氧化活性,采用水提醇沉法提取皱皮木瓜中的多糖,得多糖Ⅰ;利用Sevag法除去多糖中的蛋白质后得多糖Ⅱ;以30%H_2O_2脱除色素后再次醇沉得到精制多糖Ⅲ;透析除去小分子后利用AB-8大孔树脂进行分离以水、30%、50%、70%和95%乙醇洗脱,其中水洗脱部分多糖为Ⅳ。用苯酚-硫酸法测定多糖含量。多糖Ⅰ得率为9.83%,多糖含量(纯度,下同)为64.45%;脱蛋白后多糖Ⅱ中多糖含量为78.23%;经脱色后多糖Ⅲ含量达88.39%;大孔树脂水洗脱部分多糖Ⅳ含量为89.74%。以DPPH(2,2-二苯基-1-苦肼基)清除率和Fe~(3+)还原力方法测定木瓜多糖的抗氧化活性,木瓜多糖均体现出一定的抗氧化作用,呈浓度依赖性增强,其中多糖Ⅰ、Ⅱ表现出更好的作用。  相似文献   

3.
木聚糖酶活力测定条件研究   总被引:29,自引:2,他引:27  
用DNS法测木聚糖酶活力,分析测定条件对测定结果的影响。结果表明,在不同的条件下测定酶活力会得到不同的木聚糖酶活力测定值。其中,酶液用量、酶解反应的时间对测定结果的影响较大,酶液稀释度、DNS显色时间、DNS的用量,对测定结果也有一定的髟响。测定木聚糖酶活力的适宜条件为:酶液量/1%木聚糖液量1/9(V/V);酶解反应时间:10min;DNS用量2—2.5ml;DNS显色时间2—5min。  相似文献   

4.
目的:研究了纤维素酶在提取生物碱过程中的应用。方法:采用酶浸法和氯仿法两种不同的工艺提取马钱子生物总碱,高效液相色谱法(HPLC)测定了马钱子生物总碱中士的宁的含量。结果:酶浸法提取士的宁和氯仿法提取士的宁的含量分别为1.83%、1.32%;酶浸法和氯仿法提取马钱子生物总碱的产率分别为:2.85%、1.86%。  相似文献   

5.
祁白术多糖提取工艺研究   总被引:3,自引:0,他引:3  
以蒽酮-硫酸比色法测多糖含量,以正交优选工艺条件进行验证提取并加样测定回收率,结果显示:水提最佳条件为料液比1∶10、水浴100℃、恒温3 h,沉淀得率为48.41%,可溶性糖含量为43.83%,可溶性糖得率为21.22%;水提后醇沉条件为药液浓缩为1.5mL药液/g生药、醇沉浓度达到90%、4℃冰箱24h,醇沉得率为31.28%。水提法料液比、水提温度影响有显著性(P〈0.05)、醇沉法醇沉浓度影响有显著性(P〈0.05)。工艺验证实验平均得率31.55%,RSD=1.57%;加样回收率平均98.00%,以优选工艺方法提取、较稳定可行。  相似文献   

6.
利用水提醇沉提取东北红豆杉多糖TP,经超滤得到超滤外液TP-1和内液TP-2。TP-2进行部分酸水解和凝胶柱层析分离纯化,得到TP-2-1a。通过对理化性质、分子量、单糖组成和甲基化测定结果分析,确定其分子量分布在7.0 kDa左右,糖组成由Rha、Man、Gal、Glu、GalA和GlcA构成,摩尔比为:16.9∶1.0∶15.5∶1.3∶9.9∶2.5,中性糖以Gal的1→3、1→4连接为主,在1→3连接的O-6位上有分支;Rha以1→2连接为主,在O-4位上有分支;Man以1→4、1→6连接为主;Glu以1→3、1→4连接为主;非还原末端主要是Gal及少量的Man、Glu和Rha。酸性糖以1→4连接GalA为主,无分支。该多糖为首次从东北红豆杉中分离得到。  相似文献   

7.
目的:为保证保健食品的质量,在比较了现有大豆异黄酮的检测方法的基础上,建立了长期用于日常测定食品中大豆异黄酮的HPLC方法。方法:采用Waters Spherisorb ODS2色谱,柱温50℃,以甲醇-冰醋酸水溶液(40:60)为流动相,1.2ml/min的流速,在254nm用紫外检测器进行检测。结果:其重复测定结果的相对偏差在2.25%,回收率在85%-110%范围内。结论:该法简便、快速、灵敏度高、重现性及稳定性均较好,适用于保健食品中大豆异黄酮的测定。  相似文献   

8.
薇菜、蕺菜中氨基酸及其他营养素含量的测定   总被引:10,自引:1,他引:9  
对秦巴山区薇菜 (Osmundajaponicathunb .)、蕺菜 (Houttuyniacordatathunb.)两种山野菜可食部分中氨基酸、灰分、粗蛋白、粗脂肪、粗纤维、总糖等含量进行了测定。结果表明 :所测定的 1 7种氨基酸中 ,薇菜含 1 7种氨基酸 ,蕺菜含 1 6种氨基酸 ,七种必需氨基酸含量占各自氨基酸总量的百分数分别为 4 3 .2 6%、3 6.58%。薇菜、蕺菜灰分含量分别为 8.1 1 %、9.4 0 % ;粗蛋白含量分别为 2 2 .80 %、1 7.2 2 % ;粗脂肪含量分别为 3 .3 4 %、5.4 3 % ;粗纤维含量分别为 1 3 .0 7%、1 7.89% ;总糖含量分别为 2 1 .1 4 %、1 3 .4 2 %。  相似文献   

9.
植物组织中丙二醛测定方法的改进   总被引:458,自引:10,他引:448  
ImnrovementsofMethodforMeasurementofMalondialdehydeinvlant11-ssues丙二醇(MDA)是最常用的膜脂过氧化指标.但测定植物组织中MDA含量的经典方法《多种物质的干扰)·’,其中最主要的是。引害性糖、’。本丈在前人工作的基础L.讨如间排除可溶性糖对植物作品中M*A测定的尸扰问题作7初步探讨。材料与方法!MDA的制备[hMDA前体1.1.3.3一四乙氧基丙烷水解而成‘-2$类物质的比色测定·取2ml糖溶液,加入0.1m1210Lll。lLFeCI;·再加1.9mlo.6/硫代巴比妥酸(TBA).置沸水浴中显色15min并经2000。s离心10min)占.…  相似文献   

10.
目的:探求传统水提醇沉方法下提取半枝莲粗多糖中总糖最适高效提取方案。方法:通过传统方法以水提取有效成分,以醇除杂精制的方法,改变提取时间、温度、料液比等影响因素,对所获得的半枝莲粗多糖含量进行考查,并通过统计分析方法对工艺进行优化研究。结论:应用水提醇沉法提取半枝莲粗多糖中总糖含量的最佳工艺条件为:浸提温度100℃、料液比1∶3、浸提时间1h。  相似文献   

11.
Alpha 1-Microglobulin (alpha 1-m), or protein HC, a low molecular weight plasma protein with immunoregulatory properties, was isolated from rat serum by affinity chromatography using Sepharose-coupled monoclonal anti-alpha 1-m antibodies. High molecular weight forms of alpha 1-m were then separated from the low molecular weight alpha 1-m by gel chromatography of the eluted proteins. The apparent Mr (28,000), the charge heterogeneity, the N-linked carbohydrate, and yellow-brown chromophore suggest that the low molecular weight alpha 1-m is the serum counterpart to urinary alpha 1-m, which was purified previously. A high molecular weight complex of alpha 1-m was also isolated by the gel chromatography. It was homogeneous as judged by nondenaturing polyacrylamide gel electrophoresis. The molecule was bound by antibodies against human alpha 2-macroglobulin, and experiments with antisera against the three alpha-macroglobulin variants in rat serum, alpha 1-macroglobulin, alpha 2-macroglobulin, and alpha 1-inhibitor-3 (alpha 1I3) suggested that alpha 1I3 was the complex-partner of alpha 1-m. An antiserum raised against high molecular weight alpha 1-m was then used to isolate the complex-partner of alpha 1-m from rat serum with affinity chromatography, and this molecule was positively identified as alpha 1I3 by its physicochemical properties. Gel chromatography of the alpha 1I3.alpha 1-m complex suggested a molecule with an Mr of 266,000. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis, however, it migrated as three major molecular species with apparent molecular weights of 224,000, 205,000, and 194,000 and several minor species of both higher and lower molecular weights, suggesting a complex subunit structure. alpha 1-m and alpha 1I3 could be detected in all three major species by Western blotting, and NH2-terminal amino acid sequencing suggested a molar ratio of 1:1 of alpha 1-m and alpha 1I3 in all three species. alpha 1I3.alpha 1-m was colorless, did not show light absorbance beyond 300 nm which is typical of low molecular weight alpha 1-m and was electrophoretically homogeneous, suggesting that it lacks the chromophore. Finally, the serum concentrations of the alpha 1I3.alpha 1-m complex and free alpha 1-m were determined as 0.16 and 0.010 g/liter, respectively. Thus, alpha 1I3.alpha 1-m constitutes 1-3% of the total alpha 1I3 in rat serum (w/w) and approximately 60% of the total alpha 1-m.  相似文献   

12.
Summary p-Cresol was oxidized by hydrogen peroxide in a reaction catalysed by horseradish peroxidase and the low molecular weight products were investigated. In aqueous media Pummerer's ketone (I) was the dominating product but in organic media the product distribution was quite different; 2,2'-dihydroxy-5,5'-dimethyldiphenyl (II) was the main low molecular weight product. Similar product distributions were obtained with peroxidase adsorbed on a solid support and suspended in toluene and with peroxidase solubilized in a microemulsion containing the same solvent. The best selectivity for the formation of (II) was obtained when the enzyme was adsorbed on Celite and suspended in water-saturated chloroform with 0.5% (v/v) extra water added. The yield of low molecular weight products in this case was 28%; of this fraction, 95% was (II). Offprint requests to: P. Adlercreutz  相似文献   

13.
To explore the reason causing low yield, poor quality of Inula helenium I., this paper investigated the influence of different remained stem heights on the yield, quality and water consumption of Inula helenium I. in Gannan plateau area using field single factor randomized block method. Research results showed that Inula helenium I. which was cut before blooming period in the last ten-day of July with remained stem height of 25?cm had the lowest water consumption, the best underground root traits (including main root length, root diameter, and root dry weight per plant), and the highest yield which was higher that control group by 18.73% (P?<?.01) Moreover, Inula helenium I. with remained stem height of 25?cm had the lowest ash content while the highest alantolactone content, therefore its quality was the best. The water use efficiency (WUE) of Inula helenium I. with remained stem height of 35?cm at September was the highest (1.12?kg?h?m?2?mm?1). However, in terms of biological yield WUE and economic yield WUE, Inula helenium I. with remained stem height of 15?cm was the highest. Therefore, it can be concluded that remained stem height from 15 to 25?cm is an ideal solution, which can not only save water, but also improve yield and quality of Inula helenium I.  相似文献   

14.
1. The influence of humic substances on the association of free inorganic iron and phosphate with material of larger molecular weight was investigated in epilimnetic samples from two humus‐rich lakes of contrasting ionic strength. After modification of the molecular weight distribution of the humic substances in the samples using dialysis and ultrafiltration, the molecular weight distribution of added radioisotopes ( Fe3+ and PO43?) was assessed using gel filtration chromatography.
2. The association of Fe3+ and PO43? with larger molecular weight fractions (>50 000 and 10 000–50 000 Da) was not in general related to the quantity of humic substances of the same molecular weight in the samples. However, the proportions of Fe3+ and PO43? observed in higher molecular weight peaks were strongly correlated to the quantity of humic substances of the same molecular weight in (a) the 10 000–50 000 Da peak in the sample of low ionic strength at pH 5.5 and pH 7.0, and (b) the> 50 000 Da peak in the sample of higher ionic strength at pH 4.0.
3. It was concluded that humic substances promote the association of Fe3+ and PO43? with higher molecular weight fractions primarily by acting as peptizing agents for inorganic colloids containing Fe and P. Association of Fe3+ and PO43? with material of higher molecular weight via the formation of humic substance‐Fe3+–PO43? complexes was identified but only at specific pH and within specific molecular weight ranges for each of the epilimnetic lake water samples studied.  相似文献   

15.
The purification and some properties of two types of lipase (Lipase I and Lipase II) from Rhizopus niveus are described. The enzymes were purified to homogeneity by column chromatographies on DEAE-Toyopearl (1 pass) and CM-Toyopearl (2 passes). Lipase I consists of two polypeptide chains [a small peptide with sugar moiety (A-chain) and a large peptide of molecular weight 34,000 (B-chain)]. Lipase II has a molecular weight of 30,000 consisting of a single polypeptide chain. Lipase I appeared to be converted to Lipase II by limited proteolysis by a specific protease a small amount of which is in the culture supernatant from Rh. niveus, because one of the peptides formed has the same N-terminal sequence and C-terminal amino acid as Lipase II, as well as the molecular mass estimated by SDS-PAGE. Lipase I had a pH optimum of 6.0–6.5 and a temperature optimum of 35°C, while, for Lipase II these values were pH 6.0 and 40°C. Both enzymes were obtained in the crystalline state using the hanging drop method of vapor diffusion and PEG as the precipitating agents.  相似文献   

16.
1. Three SOD isoenzymes obtained from purified extracts of Ascaris suum were characterized. 2. The physico-chemical characteristics studied were: optimum pH, methods of preservation of enzymatic activity, molecular weight, and the u.v. and visible light absorption spectra. 3. The optimum pH for the Cu, Zn SOD I and II was 10.2 and 10.1 for the Mn SOD. 4. The extracts retained their levels of activity longer at -70 degrees C, and after lyophilization. The Mn SOD was more labile than the Cu, Zn SOD I and II. 5. The molecular weights obtained by filtration through Sephadex G-75 were: 73,000 for Mn SOD; 42,600 for Cu, Zn SOD I; and 39,800 for the Cu, Zn SOD II. 6. Both the u.v. and visible light spectra were similar to other dismutases from other sources.  相似文献   

17.
The ring-opening polymerization of ?-caprolactone catalyzed by a novel lipase Candida sp. 99-125 was achieved in organic solvents. ?-Caprolactone was found to be polymerized in quantitative yield in toluene at 80?°C for 5 days. The poly (?-caprolactone) obtained had a number-average molecular weight of 14,120 (polydispersity index?=?1.161). The effect of enzyme concentration, temperature, reaction time, reaction medium, and water content on monomer conversion and product molecular weight were investigated. Kinetic analysis showed that the enzyme displayed Michaelis–Menten kinetics and showed stronger affinity for ?-caprolactone (with a Km value of 6.1?mmol/L) than other reported lipases.  相似文献   

18.
Bacillus macerans enzyme (BME)-derived high molecular weight dextrins, which are by-products in the course of the industrial production of cylodextrins, were isolated and their chemical structures were characterized.Dextrin I was obtained in a yield of about 24% from BME-hydrolyzate (a mixture of dextrin and cylodextrins, 50% each) of potato starch by fractionation with an ultrafiltrator having a membrane of cut-off molecular weight 2.0 × 104. Dextrin II was obtained in a yield of about 15% from BME-hydrolyzate (a mixture of dextrins and cyclodextrins, 70 : 30) of Dextrin I by the same method.Dextrin I and II consisted of dextrin having molecular weights over 20 × 106 and dextrins having molecular weights 4 × 103−1 × 105 in the ratio of 80 : 12 and 66: 15, respectively.The results of hydrolysis by β-amylase and methylation analysis indicated that the average, exterior and interior chain lenghts of the dextrins having molecular weights over 20 × 106 and 4 × 103−1 × 105 from Dextrin I were 16.5, 8.2 and 7.3, and 11.5, 6.9 and 3.6, respectively, than those from Dextrin II were 13.6, 4.7 and 9.9, and 10.4, 5.1 and 4.3, respectively.  相似文献   

19.

Objective:

This study aimed to estimate utility‐based quality of life (UQoL) differences between healthy body weight and excess body weight categories.

Design and Methods:

Cross‐sectional analysis of 10,959 adults, participating in baseline data collection of the nationally representative Australian Diabetes, Obesity, and Lifestyle (AusDiab) Study was undertaken. Height and weight were measured by trained personnel. Body weight categories were assigned as healthy weight, overweight, and obesity subclasses I, II and III. UQoL was assessed using the SF‐6D, which captures physical functioning, role limitation, social functioning, pain, mental health, and vitality on a score of 0.00–1.00 (worst‐best). The relationship between body weight categories and UQoL was assessed using linear regression, adjusting for age, sex, education, and smoking.

Results:

Relative to the healthy weight group (mean UQoL score 0.77), mean adjusted UQoL differences (95% confidence intervals) were 0.001 (?0.008, 0.010) for overweight, ?0.012 (?0.022, ?0.001) for class‐I obese, ?0.020 (?0.041, 0.001) for class‐II obese, and ?0.069 (?0.099, ?0.039) for class‐III obese groups. Adding metabolic syndrome markers to the covariates had little impact on these differences.

Conclusion:

Results confirmed an inverse dose–response relationship between body weight and UQoL in this study of Australian adults. This highlights the need to incorporate UQoL measures which are sensitive to the subclasses of obesity when evaluating obesity interventions.
  相似文献   

20.
K Gekko  H Noguchi 《Biopolymers》1971,10(9):1513-1524
The number average molecular weight, Mn, of low molecular weight dextran was determined through endgroup analysis, and the intrinsic, viscosities of these materials in aqueous solution were determined at 25°C. The ultrasonic velocities in their aqueous solutions were also measured at 25 and 45°C. As concerns the molecular weight dependence of the intrinsic viscosity, partial specific compressibility of solute and the hound water around the solute, the following results were obtained. (1) log [η]-log Mn and [η]/Mn0.5 – Mn0.5 plots were in accord with the Mark-Houwink and Stockmayer-Fix-man equations respectively for Mn > 2, 000, but these plots deviated from the equations for Mn < 2, 000. (2)The partial specific compressibility, β 1°, of dextran is expressed by following equation for Mn < 2,000: β 1° = 10?12 × (13.6 log Mn - 51.7) (cm2/dyne). In contrast, it, becomes the constant value, -- 7.3 × 10?12 cm2/dyne, for Mn > 2,000. (3) The amount of bound water of dextran calculated from the sound velocity measurement lakes constant value of 0.17 ml g for Mn > 2, 000, but the amount of hydration increase with decreasing molecular weight for Mn < 2,000. From these results, a dextran molecule in aqueous solution is expected to change its conformation from random coiling to uncoiling stretched form at the molecular weight of around 2, 000 or about 12 glucose units.  相似文献   

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