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1.
魔芋葡甘聚糖的分光光度法测定   总被引:8,自引:0,他引:8  
魔芋为天南星科(Araooae)魔芋属(Amorphophallus blume)植物,是唯一大量提供葡甘聚糖(Glucomannan,下称GM)的新兴特种经济作物。魔芋GM是由D-葡萄糖和D-甘露糖主要通过β-1,4糖苷键结合的高分子多糖,在食品、医药、石油、化工、轻纺等工业中有着重要的用途。GM的定量测定虽有过甘露糖腙重量法和斐林试剂沉淀  相似文献   

2.
魔芋是天南星科魔芋属(Amorphophallus)植物的泛称,种类很多,主要产于东半球热带、亚热带。魔芋属中的一些种类块茎富含人类需要的魔芋多糖(KGM),在食品、化工、医药等领域,用途广泛。中国魔芋资源丰富,含魔芋多糖多的种类主要有花魔芋(A.rivieri)和白魔芋(A.albus)两种,常年产魔芋精粉(主要含魔芋多糖)约7000吨,四川省的产量占50%以上。  相似文献   

3.
魔芋甘露聚糖化学结构的研究   总被引:11,自引:0,他引:11  
研究了陕西花魔芋块茎中分离所得的魔芋甘露聚糖的化学结构与分子组成。经葡聚糖凝胶G-75柱层析为一组均一性多糖,气相色谱检测由甘露糖,葡萄糖组成,其克分子比Man;Glu=1.78:1,平均分子量为11×10^-5。  相似文献   

4.
魔芋块茎中粗蛋白含量5—10%,氨基酸16种总含量6.5—8%,必需氨基酸有7种。切片加工的精粉,氨基酸种类不变,但含量只有块茎中的2/5。块茎含有40—45%左右的淀粉,此外还含有单糖、多糖和粗纤维,其中粗纤维含量约4—4.5%左右。魔芋精粉中含有葡甘露聚糖48—65%左右。其含量越高,质量也越好,经济价值也就越高。  相似文献   

5.
利用高效凝胶色谱串联紫外、示差和多角度激光散射检测器(HPSEC-UV-RI-MALLS)对蜗牛黏液中的多糖进行分子量分布表征。利用气相色谱串联质谱(GC-MS)和红外光谱(FT-IR)对其化学结构进行表征;并对所获得的多糖进行抗氧化及免疫活性的评价。结果显示:蜗牛黏液中主要含有5个组分的多糖,是其重要的活性成分。对这5个多糖进行鉴定,其平均分子量为4.549×10~6、1.392×10~5、6.291×10~4、5.262×10~(4 )和4.153×10~(4 )。单糖由岩藻糖、甘露糖、葡萄糖和半乳糖组成,摩尔比为1.69∶2.46∶0.12∶1。多糖主链为→2) Manp-(1→,→3) Fucp-(1→和→3) Manp-(1→。此外,蜗牛黏液多糖具有明显的抗氧化作用,能很好地清除ABTS·~+和·OH,IC_(50)值分别为2.35和4.70 mg/mL;且能明显增强巨噬细胞(RAW264.7)的吞噬能力,促进NO和白细胞介素(IL-6)、肿瘤坏死因子(TNF-α)等免疫细胞因子的释放。  相似文献   

6.
运用紫外光谱、红外光谱、HPLC和气相色谱对葡萄糖和乳糖两种碳源获得的胞外多糖(EPS)单一组分G1、G2和L1、L2的结构进行了初步分析。结果显示不同碳源对EPS的分子结构、分子量和单糖组成都有影响。紫外光谱分析都不含蛋白和核酸;红外光谱分析G1、G2和L1、L2均呈现多糖的特征峰,但波形、特征吸收波段、波峰强度有些差异;HPLC测定G1、G2、L1和L2的平均分子量分别为6.65×105Da、1.01×104Da、2.25×106Da和1.36×104Da;气相色谱分析G1、G2和L1、L2的主要单糖组成摩尔比分别为:鼠李糖∶葡萄糖∶半乳糖=3.07∶3.29∶1;鼠李糖∶葡萄糖∶半乳糖=2.84∶6.4∶1;甘露糖∶葡萄糖∶半乳糖=17.24∶6.03∶1;甘露糖∶葡萄糖∶半乳糖=28.71∶5.98∶1。  相似文献   

7.
为探索魔芋中色素的含量与分布,采用目测和显微镜对4个种类的魔芋进行观察研究。结果显示,红魔芋、黄魔芋中的色素最多,花魔芋次之,白魔芋最少。色素体呈环状,大小为10~25μm,主要分布在叶片的栅栏组织、海绵组织和薄壁细胞中。  相似文献   

8.
我国现行栽培的魔芋主要是两个种:花魔芋和白魔芋。花魔芋是我国南方山区分布最广、栽培最多、产量高的一个种。白魔芋主要分布在川滇交界的金沙江河谷地带,品质优良,用其加工成的金江芋角一直是传统的出口物资。由  相似文献   

9.
魔芋葡甘露聚糖定量分析   总被引:5,自引:0,他引:5  
用0.1M甲酸缓冲液(pH3.0-3.2)溶胀魔芋粉,在4000转/分离心分离提取魔芋葡甘露聚糖(KGM)溶液,通过比色测定以上溶液中的游离糖和用2N硫酸水解KGM提取液后的总糖,计算出KGM含量。此法不需要純化KGM,且重现性好,准确度高,因此本法简单、准确,很适用于不同等级魔芋粉中的KGM定量分析。  相似文献   

10.
啤酒花茎尖培养   总被引:3,自引:1,他引:2  
植物名称:啤酒花(Humulus lupulus) 培养条件:分化培养基:MS+BA10~(-5)M+2,4-D10~(-6)M+GA_310~(-6)M+葡萄糖2.0%+琼脂0.85%,pH5;生根培养基:SM+BA10~(-7)M+IBA10~(-6)M+葡萄糖2%+琼脂0.85%,pH5.4;培养温度:25~27℃,光照:16小时,3000lux。  相似文献   

11.
The aim of this study was to evaluate and compare the in vitro and in vivo transdermal potential of w/o microemulsion (M) and gel (G) bases for diclofenac sodium (DS). The effect of dimethyl sulfoxide (DMSO) as a penetration enhancer was also examined when it was added to the M formulation. To study the in vitro potential of these formulations, permeation studies were performed with Franz diffusion cells using excised dorsal rat skin. To investigate their in vivo performance, a carrageenan-induced rat paw edema model was used. The commercial formulation of DS (C) was used as a reference formulation. The results of the in vitro permeation studies and the paw edema tests were analyzed by repeated-measures analysis of variance. The in vitro permeation studies found that M was superior to G and C and that adding DMSO to M increased the permeation rate. The permeability coefficients (Kp) of DS from M and M+DMSO were higher (Kp=4.9×10−3±3.6×10−4 cm/h and 5.3×10−3±1.2×10−3 cm/h, respectively) than the Kp of DS from C (Kp=2.7×10−3±7.3×10−4 cm/h) and G (Kp=4.5×10−3±4.5×10−5 cm/h). In the paw edema test, M showed the best permeation and effectiveness, and M+DMSO had nearly the same effect as M. The in vitro and in vivo studies showed that M could be a new, alternative dosage form for effective therapy.  相似文献   

12.
感染松墨天牛的金龟子绿僵菌菌株的初步筛选   总被引:14,自引:0,他引:14  
松墨天牛是松材线虫病的主要媒介昆虫,本文对分离自松墨天牛的6株金龟子绿僵菌,以及从光肩星天牛、大蜡螟、伊藤厚丝角叶蜂和土蝽上分离的各1个菌株,共10个菌株的产孢情况、孢子萌发率进行研究;在此基础上选出金龟子绿僵菌1291、1349和2049三个菌株及球孢白僵菌F-263菌株,采用成虫跗节接种法和幼虫浸渍法进行室内松墨天牛及大蜡螟的毒力测定比较。结果表明,供试绿僵菌菌株对松墨天牛幼虫在接种15天后的感染僵虫率为76.9%~93.1%(1×107孢子/mL);成虫在接种20天后的僵虫率亦达57.9%~75.0%(6.5×105~3.4×106孢子/成虫);2049菌株表现尤其突出;对应的球孢白僵菌F-263对幼虫和成虫的僵虫率分别是96.3%(1×107孢子/mL)和55%(9.7×105孢子/成虫)。但这3个金龟子绿僵菌菌株对大蜡螟的毒力较低,存在较明显的寄主专化性。这3个菌株今后在防治松墨天牛方面具有较大开发应用价值。  相似文献   

13.
The cell-growth-inhibitory and phase-specific effects of D-penicillamine on cell-cycle progression were investigated using cell-proliferation patterns, quantitative cell-cycle analysis by flow cytometry, and determination of the mitotic index and binucleate cell fraction of normal (rabbit articular chondrocytes, L 809, rabbit fibroblasts) and transformed (HeLa, L 929) cells. D-penicillamine treatment resulted in an inhibition of growth within a dose range of 5 × 10?4 M to 7.5 × 10?3 M. Examination of DNA by flow cytometric analysis revealed that rabbit articular chondrocytes were preferentially arrested in the G0/1 phase of the cell cycle, whereas the other cell lines were blocked in the G2 + M phase; the increase in the proportion of cells with G2 + M DNA content was partially due to an enhancement of binucleate cells, resulting in a cytokinesis perturbation for HeLa and L 929 cells. These results showed that D-penicillamine affects cell proliferation through different events according to cell type.  相似文献   

14.
Yoon SH  Robyt JF 《Carbohydrate research》2002,337(21-23):2245-2254
It was found that Bacillus macerans cyclomaltodextrin glucanotransferase (CGTase) reacts with cyclomaltohexaose (alpha-cyclodextrin, alpha-CD) to give a series of cyclomaltooligosaccharides (cyclomaltodextrins, CDs), having seven to more than 20 D-glucose residues and maltooligosaccharides (maltodextrins, MDs) from G5 to G12+. When D-glucose (Glc) was added to the alpha-CD at very low molar ratios (1:100) of Glc to alpha-CD, the predominant products (95%) were CDs, some of which were macrocyclic MDs with 20-60 D-glucose residues, along with MDs that also had high molecular weights, containing 10-75 D-glucose residues and gave a blue iodine-iodide color. As the molar ratio of Glc to alpha-CD was increased, the amount of CDs progressively decreased and MDs proportionately increased in the range of G2-G12. At 25 mM alpha-CD and Glc to alpha-CD molar ratio of 1:1, a 75% yield of MDs, G1-G12, each in approximately equal amounts, was obtained; and at 20 mM and a 5:1 ratio, a 97% yield of MDs, G2-G9, was obtained but in unequal amounts. At higher ratios (10:1), the CDs completely disappeared, and at very high ratios (50:1 to 100:1) only low-molecular-weight MDs, G2-G4, were formed.  相似文献   

15.
Objective: To develop accurate and reliable equations from simple anthropometric parameters that would predict percentage of total body fat (%BF), total abdominal fat (TAF), subcutaneous abdominal adipose tissue (SCAT), and intra‐abdominal adipose tissue (IAAT) with a fair degree of accuracy. Methods and Procedures: Anthropometry, %BF by dual‐energy X‐ray absorptiometry (DXA) in 171 healthy subjects (95 men and 76 women) and TAF, IAAT, and SCAT by single slice magnetic resonance imaging (MRI) at L3–4 intervertebral level in 100 healthy subjects were measured. Mean age and BMI were 32.2 years and 22.9 kg/m2, respectively. Multiple regression analysis was used on the training data set (70%) to develop equations, by taking anthropometric and demographic variables as potential predictors. Predicted equations were applied on validation data set (30%). Results: Multiple regression analysis revealed the best equation for predicting %BF to be: %BF = 42.42 + 0.003 × age (years) + 7.04 × gender (M = 1, F = 2) + 0.42 × triceps skinfold (mm) + 0.29 × waist circumference (cm) ? 0.22 × weight (kg) ? 0.42 × height (cm) (R 2 = 86.4%). The most precise predictive equation for estimating IAAT was: IAAT (mm2) = ?238.7 + 16.9 × age (years) + 934.18 × gender (M = 1, F = 2) + 578.09 × BMI (kg/m2) ? 441.06 × hip circumference (cm) + 434.2 × waist circumference (cm) (R 2 = 52.1%). SCAT was best predicted by: SCAT (mm2) = ?49,376.4 ? 17.15 × age (years) + 1,016.5 × gender (M = 1, F = 2) +783.3 × BMI (kg/m2) + 466 × hip circumference (cm) (R 2 = 67.1). Discussion: We present predictive equations to quantify body fat and abdominal adipose tissue sub‐compartments in healthy Asian Indians. These equations could be used for clinical and research purposes.  相似文献   

16.
发状念珠藻胞外多糖的纯化与性质分析   总被引:1,自引:0,他引:1  
于海峰  贾士儒 《微生物学报》2008,24(6):1029-1034
采用DEAE阴离子交换层析和Sephadex G100凝胶层析对液体悬浮培养发状念珠藻胞外多糖进行纯化, 得到两个组分NFPS1和NFPS2。对组分NFPS2进行理化性质分析, 并与野生发状念珠藻多糖NFPS0的性质进行对比。结果表明二者具有相似的单糖组成, 均为葡萄糖、木糖、半乳糖、甘露糖; 表观分子量分别为2.79×105、2.26×105; 均不含核酸、蛋白质等物质, 是非硫酸化多糖; 有较高的热稳定性, 其降解温度在245oC左右。但在微观结构上, 两者存在一定差别。  相似文献   

17.
采用DEAE阴离子交换层析和Sephadex G100凝胶层析对液体悬浮培养发状念珠藻胞外多糖进行纯化, 得到两个组分NFPS1和NFPS2。对组分NFPS2进行理化性质分析, 并与野生发状念珠藻多糖NFPS0的性质进行对比。结果表明二者具有相似的单糖组成, 均为葡萄糖、木糖、半乳糖、甘露糖; 表观分子量分别为2.79×105、2.26×105; 均不含核酸、蛋白质等物质, 是非硫酸化多糖; 有较高的热稳定性, 其降解温度在245oC左右。但在微观结构上, 两者存在一定差别。  相似文献   

18.
Studies were undertaken to identify cell surface markers specific for different phases of the cell cycle. Antisera were prepared in rabbits against membrane protein preparations from synchronized BW 5147 cells, an AKR mouse T-lymphoma cell line, in the G1, S, G2 or M phases of the cell cycle. These antisera were used to precipitate radioiodinated surface proteins from synchronized cells in the different phases. The immunoprecipitates were quantitatively analyzed by sodiumdodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Cells in S phase had significantly higher concentrations of proteins weighing 70 × 103 and 165 × 103 D than cells in G1 or G2 phase. The other major labeled surface components did not vary. These results were confirmed by quantitative absorption of the antisera with synchronized cells. Comparative analysis of the antisera showed that the 165 × 103 D peak contained at least two antigens, one recognized by both a-G1 and a-S and the other by a-G1 only. Though cells in S phase had large quantities of the 70 × 103 D protein, intact and SDS-solubilized membrane preparations from S phase could not elicit in rabbits any antibody against that protein. These antisera did, however, have good antibody titers to the other major protein peaks and the antisera developed against cells in G1, G2 or M had good anti-70 × 103 activity. The results suggest a qualitative molecular change in the 70 × 103 protein during S phase.  相似文献   

19.
Membrane receptors for Vicia graminea (Vg) lectin on human red cells were analyzed using deoxycholate lysates obtained from 125I-erythrocyte membranes incubated with a purified lectin immobilized on Sepharose 4B. The glycoproteins (GP) specifically bound to the gel were eluted and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. Using native erythrocytes the results obtained demonstrate that N red cells have exposed Vg receptors located on GPα (synonym glycophorin A) and GPδ (synonym glycophorin B) whereas on M erythrocytes the Vg receptors are restricted to GPδ. The presence of Vg receptors was also found on the hybrid glycoprotein (made of the N-ter of GPδ and C-ter of GPα) carried by St(a+) erythrocytes. A similar amount of radioactivity was bound to Vg-Sepharose incubated with neuraminidase-treated N or M membranes. The material eluted was tentatively identified as asialo GPα and asialo GPδ, suggesting that numerous receptors have been uncovered mainly on asialo GPα species from M erythrocytes. No glycoprotein component could be identified from the material eluted from Vg Sepharose incubated with native or neuraminidase-treated membrane from a Tn(+) individual. Scatchard plot analysis obtained from binding experiments at equilibrium with M, N, and St(a+) cells revealed the existence of at least two classes of receptors both on native and neuraminidase-treated erythrocytes. Desialylation of the M, N, and St(a+) erythrocytes resulted in an increase in the number of low- and high-affinity binding sites but had no significant effect on the association constants. However, high-affinity binding constants were about six times higher with N (7.07 × 107 and 6.61 × 107m?1 for native and neuraminidase-treated N cells, respectively) as compared to M erythrocytes (1.13 × 107 and 1.17 × 107m?1 for native and neuraminidase-treated M cells, respectively) whereas the low-affinity binding constants were similar for all types of cells (in the range of 0.1 to 0.3 × 107m?1). The number of Vg binding sites increases from 0.085 × 105 to 0.8 × 105 (high affinity) and from 2.10 × 105 to 6.25 × 105 (low affinity) per native and neuraminidase-treated N cell, respectively. On native and neuraminidase-treated M cells the number of Vg receptors increases from 0.011 × 105 to 0.51 × 105 (high affinity) and 0.13 × 105 (low affinity), respectively. The large increase in the number of Vg receptors on neuraminidase-treated M cells is correlated with a large increase in agglutinability. Under similar treatment St(a+) cells behave like N erythrocytes whereas only 0.16 × 105 Vg receptors of low affinity could be detected on neuraminidase-treated Tn erythrocytes. The results demonstrate that sialic acid is not required for binding and favor the view that the binding site of V. graminea lectin accommodates with two types of erythrocyte membrane receptors, one including both a contribution of polypeptide and oligosaccharide chains and a second which involves a simple interaction with sugar sequence Galβ1–3GalNAc available only when sialic acids are removed. The latter disaccharide is recognized by the Arachis hypogea lectin which therefore inhibits further binding of the V. graminea to neuraminidase-treated erythrocytes.  相似文献   

20.
Phillips , Lyle L. (North Carolina State Coll., Raleigh.) Segregation in new allopolyploids of Gossypium. IV. Segregation in New World × Asiatic and New World × wild American hexaploids. Amer. Jour. Bot. 49(1): 51–57. 1962.—The New World tetraploid cottons, G. hirsutum and G. barbadense, are natural amphidiploids (genome formula, 2 [AD]) combining species of the cultivated Asiatic (2A) and wild American (2D) groups of diploid cottons. Genetic segregation for marker alleles in New World × Asiatic and New World × wild American synthetic hexaploids have been determined. Average segregation for several loci in New World × Asiatic hexaploids is close to the autoploid 5:1 ratio, ranging from 5.1 to 6.8:1. Average segregation for 3 loci (L, Rd, and R1) common to a series of New World × wild American hexaploids is: New World × G. raimondii, 9.3:1;–× G. harknessii, 16.4:1;–× G. armourianum, 17.4:1;–× G. aridum, 20.3:1;–× G. lobatum, 21.4:1–× G. thurberi, 32.9:1;–× G. gossypioides, 66.5:1. These data are discussed, and the method by which they were derived is compared with other cytogenetical means of discerning phylelic interrelationships among Gossypium species.  相似文献   

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