Chemical Properties of a Polysaccharide Purified From Solid‐State Fermentation of Auricularia Auricular and its Biological Activity as a Hypolipidemic Agent

A water‐soluble crude polysaccharide was extracted by hot water from Auricularia auricular mycelium grown under solid‐state fermentation (SSF). The crude polysaccharide was purified by DEAE Sephadex A‐50 and Sephadex G‐200 chromatography. Fourier transform infrared spectroscopy and nuclear magnetic resonance (¹H NMR) spectroscopy were used to investigate the structure of the purified A. auricular polysaccharide (AAP‐I) and revealed that it is α‐glycosidically linked. After 14 and 28 days of AAP‐I orally administered, the AAP‐I significantly decreased the levels of total cholesterol, triglyceride, and low‐density lipoprotein cholesterol in mice in which hyperlipidemia had been induced by a high fat diet (P < 0.05). The results revealed that AAP‐I from SSF of A. auricular mycelium possesses potent hypolipidemic properties. The polysaccharide may be useful as a functional food additive and a hypolipidemic agent.     

Chemical characteristics and antioxidant activities of polysaccharide purified from the seeds of Plantago asiatica L.

BACKGROUND: A water‐soluble polysaccharide from the seeds of Plantago asiatica L. (P. asiatica L. polysaccharide, PLP) was extracted with hot water and purified by gel filtration chromatography. The chemical characteristics of PLP were determined by high‐performance gel permeation chromatography (HPGPC) and Fourier transform infrared (FTIR) spectroscopy. In addition, the antioxidant activities of PLP in vitro were evaluated using various test systems, including scavenging of 1,1‐diphenyl‐2‐picryl‐hydrazyl (DPPH) radicals, scavenging of superoxide radicals generated by 1,2,3‐phentriol autoxidation, scavenging of hydroxyl radicals and inhibition of lipid peroxidation. RESULTS: The molecular weight of PLP was determined by HPGPC to be about 1894 kDa. PLP contained 29.2 g kg^?1 protein and 145.8 g kg^?1 uronic acid. The FTIR spectrum of PLP also revealed typical characteristics of a polysaccharide containing protein and uronic acid. Moreover, the results showed that PLP possessed antioxidant activities, but lower than those of ascorbic acid. CONCLUSION: PLP is an acid protein‐bound polysaccharide of high molecular weight, but its structure needs further study. The present results suggest that PLP could potentially be used as a natural antioxidant. Copyright © 2009 Society of Chemical Industry     

Structural characterisation and immunomodulatory effects of polysaccharides isolated from Dendrobium aphyllum

A crude polysaccharide extract of Dendrobium aphyllum (cDAP, yield 38.15 ± 0.20%) was generated. The D. aphyllum polysaccharide (DAP, M_w 471.586 kDa), purified by DEAE‐Sepharose and Sephadex‐G200 Fast Flow, was composed of mannose (71.3%) and glucose (28.7%), according to GC–MS analysis. Its backbone was composed of β‐d ‐mannopyranose and β‐d ‐glucopyranose residues, as revealed by infrared spectroscopic analysis. Its glycosidic bond was mainly 1, 4‐linked, and the O‐acetyl groups were mainly linked to mannose residues, according to periodate oxidation and Smith degradation analysis. The DAP units polymerised into a filiform‐shaped spatial pattern, as characterised by atomic force microscopy and scanning electron microscopy. DAP treatment enhanced cytokine secretion (nitric oxide, interleukin‐6 and tumour necrosis factor‐α) and pinocytic and phagocytic capacities of RAW 264.7 mouse macrophages. The complement receptor 3 and mannose receptor were identified to be the receptors of DAP on RAW 264.7 cells, indicating that the Akt/mTOR/MAPK and IKK/nuclear factor‐?B pathways could be involved in DAP‐activated immunomodulation.     

Purification and structural elucidation of a novel fucoglucan from the fruiting bodies of Phellinus baumii Pilát

BACKGROUND: Recently, much attention has focused on the biological properties of fungal polysaccharides. Polysaccharides extracted from Phellinus baumii Pilát are reported to have antitumor and immunostimulatory properties, as well as anti‐mutagenicity activity, hypoglycemic and free radical scavenging properties. In this paper, we report the chemical and structural characterization of a novel neutral polysaccharide isolated from the fruiting bodies of P. baumii Pilát. RESULTS: PBF4, a purified polysaccharide, was isolated from the fruiting bodies of P. baumii Pilát, and was shown to be composed of L ‐fucose and D ‐glucose in a ratio of 1:4. It was found to be a fucoglucan consisting of a α‐(1 → 4)‐D ‐glucopyranose backbone with some insertions of α‐(1 → 2)‐L ‐Fucp residues. It also contained a minor β‐(1 → 4,6)‐linked D ‐glucopyranosyl and β‐glycosidically linked nonreducing‐end D ‐glucopyranosyl residues. CONCLUSION: Our results add a new polysaccharide to those already described for different fungal groups. This kind of polysaccharide is useful for further study of the structure–function relationships and mechanism responsible for its biological activities. Copyright © 2008 Society of Chemical Industry     

Structural characterization and antioxidant activities of 2 water-soluble polysaccharide fractions purified from tea (Camellia sinensis) flower

Abstract: The water‐soluble crude polysaccharide tea flower polysaccharide (TFP), obtained from tea (Camellia sinensis) flower by boiling‐water extraction and ethanol precipitation, was fractionated by Sephadex G‐100 column chromatography, giving 2 polysaccharide fractions termed TFP‐1 and TFP‐2. The structural features of TFP‐1 and TFP‐2 were investigated by high‐performance liquid chromatography (HPLC), gel‐permeation chromatography (GPC), rheometer, infrared (IR) spectra, nuclear magnetic resonance (NMR) spectroscopy, atomic force microscope (AFM), and scanning electron microscope (SEM). Results indicated that TFP‐1 was composed of glucose: xylose: rhamnose: galactose = 1.0:1.2:0.81:0.98 with a molecular weight of 167.5 KDa, while TFP‐2 comprised glucose: xylose: rhamnose: arabinose = 1.0:0.76:2.3:2.3 with a molecular weight of 10.1 KDa. The ¹H NMR revealed that TFP‐1 contained α‐L‐Rhap, α‐D‐Galp, α‐D‐GalpNAc, α‐D‐Xylp, α‐D‐Glcp, and β‐D‐Glcp residues, while TFP‐2 was illustrated to have α‐L‐Rhap, α‐L‐Arap, α‐D‐Xylp, α‐D‐Glcp, and α‐D‐GlcpNAc residues. Antioxidant activities of these fractions were investigated using various in vitro assay systems compared with ascorbic acid. In conclusion, TFP‐2 exhibited the higher antioxidant activities and could be explored as a novel potential antioxidant. Practical Application: At present, commonly low‐grade tea is preferred to extract the tea polysaccharide, to take full advantage of tea flower resource to extract polysaccharides can greatly reduce the cost of tea products. Thus, the search for plant‐derived biomaterials from this study could generate natural value‐added products from underutilized tea plant waste and used as a medicinal agent against chronic health problems, such as cancers, aging, and atherosclerosis caused by reactive free radicals that produced from oxidation.     

冬枣多糖的分离纯化及抗氧化活性研究

目的：分离纯化冬枣多糖,并研究其组分、结构特征和抗氧化活性。方法：采用水提醇沉、脱蛋白脱色、DEAE-52纤维素柱和Sephadex G-100凝胶色谱柱分离纯化冬枣多糖;利用Sephadex G-100凝胶色谱柱进行纯度鉴定和分子质量的测定;通过紫外光谱、红外光谱、气相色谱法进行了初步结构分析;采用邻二氮菲法和1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）体系对纯化多糖进行抗氧化活性的研究。结果：冬枣多糖经DEAE-52分离和Sephadex G-100纯化得到2 个组分DPA和DPB,经Sephadex G-100鉴定均为均一组分,DPA和DPB分子质量分别为1.04×104、3.02×105 D,不含蛋白质和核酸,为吡喃型糖苷环骨架,DPA的单糖组成为阿拉伯糖、甘露糖、葡萄糖、半乳糖,其物质的量比为6.66∶1.00∶6.75∶2.09;DPB的单糖组成为鼠李糖、阿拉伯糖、甘露糖、葡萄糖、半乳糖,其物质的量比为4.33∶10.90∶1.00∶3.25∶4.78;DPA和DPB均具有一定的抗氧化活性,随着多糖质量浓度的增加,其抗氧化活性增强,在质量浓度为8 mg/mL时对羟自由基清除率分别为28.52%、78.79%,在质量浓度为0.4 mg/mL时对DPPH自由基清除率分别为9.97%、24.54%。结论：DPA和DPB均具有一定的抗氧化活性。     

不同碳源对阿魏菇菌丝生长量及多糖产量的影响

阿魏菇是一种极具发展前景的食药两用大型真菌,实验用液体摇床培养法与平板培养法培养阿魏菇,对其在不同碳源培养基中的胞外多糖产量及菌丝生长情况进行了研究。结果表明,蔗糖为阿魏菇生长利用的最佳碳源,液体培养基中菌球长势好,胞外多糖产量高,平板培养菌丝生长速度快。葡萄糖作碳源培养前期胞外多糖量增加快,但胞外多糖产量和菌丝量不如蔗糖作碳源时高。以麦芽糖作碳源液体培养菌球生长不完整。阿魏菇对乳糖利用情况最差,胞外多糖产量及菌丝量均为最低。     

Rheological Properties,Molecular Distribution,and Microstructure of Fortunella margarita (Lour.) Swingle Polysaccharides

Fortunella margarita polysaccharides (FMPS) are one of the main bioactive components of F. margarita. The activity is related to their rheological properties and structure. The objective of this study was to investigate the relationship between rheological properties, molecular distribution, and microstructure of crude FMPS (C‐FMPS) and purified FMPS (P‐FMPS). The results showed that both of solutions were shear‐thinning pseudoplastic fluids with flow properties in line with the Power Law model. The pseudoplasticity of P‐FMPS was stronger compared to C‐FMPS. Additionally, the molecular weight and polydispersity of P‐FMPS were greater, whereas the molecular radius was less compared to C‐FMPS. The surface of C‐FMPS was rough and dense whereas P‐FMPS displayed a smooth network structure by environment scanning electron microscopy. According to confocal laser scanning microscopy, C‐FMPS dispersed in the medium without connected network, whereas the network of P‐FMPS was unevenly distributed in the medium and the shape was compact and smooth. The molecular distribution and microstructure of P‐FMPS were attributed to the purification process while rearrangement and aggregation of polysaccharide molecules took place, which resulted in the significant difference of rheological properties between C‐FMPS and P‐FMPS.     

远志多糖的分离纯化、结构特征及生物活性

目的:分离纯化远志多糖(polysaccharide of Polygala tenuifolia,PTP),并对其理化性质、抗氧化和降血糖活性进行研究。方法:采用超声波辅助提取、分级醇沉、DEAE-cellulose 52和Sephadex G-100柱色谱分离纯化远志多糖;紫外-可见光谱扫描法、比旋光度法、凝胶渗透色谱法3种方法验证纯度;高效凝胶渗透色谱法测定相对分子质量,高效阴离子交换色谱测定单糖组成;清除1,1-二苯基-2-苦味基肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基和羟自由基评价体外抗氧化活性;测定对α-葡萄糖苷酶抑制能力以研究其降血糖活性。结果:远志多糖经分离纯化后获得组分PTP-1,经3种方法验证PTP-1为均一性良好的多糖,相对分子质量为4.62×10~4,由半乳糖、葡萄糖、甘露糖组成,物质的量比为3.92∶1.00∶2.08。抗氧化活性研究结果表明,PTP-1对清除DPPH自由基和羟自由基呈良好的量效关系,半数清除率浓度IC_(50)分别为0.35 mg/m L和0.51 mg/m L。降血糖活性结果表明,PTP-1对α-葡萄糖苷酶具有较好的抑制能力,IC_(50)值为0.52 mg/m L。结论:远志多糖PTP-1为具有抗氧化和降血糖活性的均一多糖。     

鹰嘴豆非淀粉多糖的分离纯化及结构表征

提取鹰嘴豆中的粗多糖,通过酶处理和Sevag法除去多糖中的淀粉和蛋白质,经DEAE-52纤维素柱和Sephadex G-75凝胶柱分离纯化分别得到鹰嘴豆非淀粉中性多糖和酸性多糖,并通过紫外光谱、气相色谱、红外光谱、扫描电镜测定其性质和单糖组成。结果表明：鹰嘴豆非淀粉多糖在260 nm和280 nm波长处均无吸收峰,表明两种多糖均不含核酸、蛋白质以及肽类等;气相色谱测定表明鹰嘴豆非淀粉中性多糖单糖组成的物质的量比为鼠李糖∶岩藻糖∶阿拉伯糖∶木糖∶甘露糖∶半乳糖∶葡萄糖=2.48∶1∶3.92∶0.87∶32.82∶18.79∶28.06,鹰嘴豆非淀粉酸性多糖单糖组成物质的量比为鼠李糖∶岩藻糖∶阿拉伯糖∶木糖∶甘露糖∶半乳糖∶葡萄糖=2.22∶1∶3.92∶2.10∶5.92∶15.99∶8.57（均以岩藻糖为标准）;红外光谱测定表明二者均有多糖的特征吸收峰;扫描电镜显示鹰嘴豆非淀粉中性多糖呈线形结构而鹰嘴豆非淀粉酸性多糖呈卷曲的片状结构。     

辣木叶多糖的分离纯化及其体外降糖活性研究

目的研究辣木叶多糖的制备、单糖组成以及体外降糖活性。方法采用水提醇沉、Sevage法、大孔树脂-阴阳离子交换树脂联用技术得到较高纯度辣木叶粗多糖,再进一步通过二乙氨基乙基纤维素和葡聚糖凝胶柱层析分离得到2个主要多糖组分(MOs-2-a、MOs-2-b),并通过水解衍生化对其单糖组成进行分析。此外,采用HepG2细胞建立胰岛素抵抗模型,以细胞葡萄糖消耗量为指标,考察辣木叶多糖的降糖作用。结果本文采用的制备工艺可以得到较高纯度的辣木叶粗多糖(纯度为73.10%),辣木叶多糖主要由甘露糖、鼠李糖、葡萄糖及半乳糖组成,其中各单糖摩尔比为0.49:3.65:0.63:1.27。与模型组相比,辣木叶多糖组分MOs-2-a、MOs-2-b均能显著增加胰岛素抵抗HepG2细胞的葡萄糖消耗量(P0.05)。结论辣木叶多糖MOs-2-a、MOs-2-b具有良好的降糖效果,本文可以为辣木叶多糖作为功能食品发展的提供科学依据。     

南瓜中降血糖活性成分的提取及其功能性质的研究

为探寻南瓜中对正常及糖尿病模型小鼠血糖有影响的有效成分 ,本实验采用新的分离工艺从南瓜粉中提取得到南瓜粗多糖 (PP) ,用DEAE分级获得 3个组分 ,收集的主导组分经过SephadexG 10 0柱分级 ,以小白鼠血糖值作为筛选活性成分的指标 ,收集有活性的组分(PP CG)经SephadexG 2 0 0证实为单一峰。气相色谱分析其单糖组成为葡萄糖、半乳糖、阿拉伯糖及鼠李糖。高效液相色谱证明其为杂多糖 ,分子质量为 1.16× 10 5u。     

Microwave‐Assisted Extraction,Chemical Structures,and Chain Conformation of Polysaccharides from a Novel Cordyceps Sinensis Fungus UM01

Cordyceps sinensis is a well‐known tonic food with broad medicinal properties. The aim of the present study was to investigate the optimization of microwave‐assisted extraction (MAE) and characterize chemical structures and chain conformation of polysaccharides from a novel C. sinensis fungus UM01. Ion‐exchange and gel filtration chromatography were used to purify the polysaccharides. The chemical structure of purified polysaccharide was determined through gas chromatography‐mass spectrometry. Moreover, high performance size exclusion chromatography combined with refractive index detector and multiangle laser light scattering were conducted to analyze the molecular weight (M_w) and chain conformation of purified polysaccharide. Based on the orthogonal design L₉, optimal MAE conditions could be obtained through 1300 W of microwave power, with a 5‐min irradiation time at a solid to water ratio of 1:60, generating the highest extraction yield of 6.20%. Subsequently, the polysaccharide UM01‐S1 was purified. The UM01‐S1 is a glucan‐type polysaccharide with a (1→4)‐β‐d ‐glucosyl backbone and branching points located at O‐3 of Glcp with a terminal‐d ‐Glcp. The M_w, radius of gyration (R_g) and hydrodynamic radius (R_h) of UM01‐S1 were determined as 5.442 × 10⁶ Da, 21.8 and 20.2 nm, respectively. Using the polymer solution theory, the exponent (ν) value of the power law function was calculated as 0.38, and the shape factor (ρ = R_g/R_h) was 1.079, indicating that UM01‐S1 has a sphere‐like conformation with a branched structure in an aqueous solution. These results provide fundamental information for the future application of polysaccharides from cultured C. sinensis in health and functional food area.     

PURIFICATION AND CHARACTERIZATION OF A CATALASE FROM THE LIVER OF BULLFROG, RANA CATESBEIANA SHAW

A catalase was purified from the liver of bullfrog, Rana catesbeiana Shaw, after extraction, ammonium sulfate precipitations, DEAE‐Sephadex A‐50 chromatography, gel filtration chromatography on a Sephadex G‐150 column, ion exchange chromatography on a DEAE‐Sephacel column and Sephacryl S‐300 column. The yield and purification from the starting crude extract were 0.25% and 73.57‐fold, respectively. The purified catalase with an apparent molecular mass of 186 kDa was shown to be composed of four identical subunits of apparent molecular mass of 47.7 kDa. The purified catalase is active over a broad pH range of 6.0–10.0, and it has an isoelectric point of 6.3. The enzyme showed a K_mfor H₂O₂of 20 mM and an apparent V_maxof 51.91 U/mg, and its maximum absorption was at 408 nm in the visible portion of the spectrum. In addition, the purified enzyme was markedly inhibited by azide, cyanide and hydroxylamine.     

ISOLATION AND ANALYSIS OF A NOVEL ACIDIC POLYSACCHARIDE WITH GLUCOKINASE-STIMULATING ACTIVITY FROM COARSE GREEN TEA

Water‐soluble polysaccharides from coarse green tea were separated by anion‐exchange chromatography into five fractions (fraction A [FA], fraction B, fraction C [FC], fraction D and fraction E). Two of these fractions, FA and FC, contained significant glucokinase‐stimulating activity (P < 0.05). The major component, FC, showed the most activity, and thus, was further purified by gel filtration chromatography, thereby obtaining fraction C‐1 (FC‐1) and fraction C‐2 (FC‐2). The biological activity of the two fractions was investigated, and FC‐1 displayed higher glucokinase‐stimulating activity (P < 0.01). Chemical tests combined with IR and UV spectroscopy revealed that FC‐1 is an acidic polysaccharide without conjugation to protein. Sugars of FC‐1 are composed of rhamnose, arabinose, mannose, glucose and galactose in the ratio of 12.57:22.95:4.4:39.34:20.77. Uronic acid analysis by ion chromatography showed that FC‐1 contains 8% galacturonic acid, and its molecular weight was estimated to be approximately 6 × 10⁴ using a Sephacryl S200 column. These results are different from the observations previously reported, therefore suggesting that FC‐1 is a novel polysaccharide.     

美味牛肝菌丝体与野生子实体营养成分的比较分析

采用原子吸收分光光度法、高效液相色谱等方法对美味牛肝菌液体培养菌丝体与野生子实体主要营养成分及含量进行测定。结果表明,美味牛肝菌液体培养菌丝体和野生子实体均含有蛋白质、多糖、氨基酸、脂肪、纤维、矿物质等多种营养成分,其组成基本一致,但菌丝体在多种成分的质量分数上均高于野生子实体。     

PURIFICATION AND CHARACTERIZATION OF A SERINE PROTEINASE FROM THE TUNA PYLORIC CAECA

A 15.0 kDa serine proteinase with collagenase activity from pyloric caeca of tuna, Thunnus thynnus, was purified in four steps; acetone precipitation, gel filtration chromatography on a Sephadex G‐100, ion‐exchange chromatography on a DEAE‐Sephadex α‐50 and gel filtration chromatography on a Sephadex G‐75 column. The purification and yield were 30.5‐fold and 0.023%, respectively, as compared with those in the starting crude extract. The optimum pH and temperature for the purified collagenolytic enzyme were around pH 7.5 and 55C, respectively. The purified proteinase was strongly inhibited by metal ions (Hg²⁺ and Zn²⁺) and serine proteinase inhibitors (PMSF, TLCK and soybean trypsin inhibitor) suggesting it is a serine protease. The K_m and V_max of the purified enzyme for collagen type I were approximately 3.82 mM and 851.5 U, respectively.     

莲子红衣多糖的分离纯化及结构表征

以莲子红衣为实验对象,将其中的多糖进行分离、纯化并表征结构。采用酶提醇析法提取莲子红衣粗多糖,选择DEAE-C阴离子交换树脂和Sephadex G-25凝胶柱层析,从莲子红衣粗多糖中分离纯化得到中性多糖和酸性多糖两种组分。经凝胶渗透色谱测定,中性和酸性多糖的重均分子质量分别为3.78×104 D和4.94×104 D,纯度分别为91.16%和90.24%。中性多糖组分由葡萄糖、木糖、甘露糖、半乳糖4 种单糖组成;酸性多糖组分由葡萄糖、木糖、半乳糖、岩藻糖、阿拉伯糖5 种单糖组成。红外光谱证明两种多糖中均含有糖类特征吸收峰,且为α构型的吡喃型多糖。核磁共振氢谱检测又进一步证实了两种多糖均为α构型。     

南瓜活性多糖的降糖作用及其组成分析

为研究南瓜多糖对正常及糖尿病模型小鼠血糖的影响 ,本实验采用新的分离工艺从南瓜粉中提取得到南瓜粗多糖 (PP) ,用DEAE分级获得 3个组分 ,收集的主导组分过SephadexG 10 0柱 ,获得 2个组分 .收集有活性的组分 (AP) ,经SephadexG 2 0 0柱 ,证实为单一峰 .以葡萄糖为标准 ,苯酚 硫酸法测得总糖质量分数为 80 .6 % ;气相色谱分析其单糖组成为葡萄糖、半乳糖、阿拉伯糖及鼠李糖