Isolation and antioxidant property of the extracellular polysaccharide from <Emphasis Type="Italic">Rhodella reticulata</Emphasis>

The extracellular polysaccharide from Rhodella reticulata was separated from the culture medium followed by concentration and ethanol precipitation, and purified by anion exchange chromatography on DEAE-Sepharose Fast Flow. This study compared the free radical-scavenging property and antioxidant activity with various treatments of crude extracellular polysaccharides of R. reticulata. The results showed that both the crude extracellular polysaccharide and deproteinized crude extracellular polysaccharide gave evidence of the free radical scavenging and antioxidant activity in a dose-dependent manner. The crude extracellular polysaccharide exhibited higher free radical scavenging capacity and better antioxidant activity than the various treatments of crude extracellular polysaccharide samples. The superoxide anion radical scavenging ability of various samples was significantly higher compared to standard antioxidant (α-tocopherol). These results indicate that the extracellular polysaccharide of R. reticulata is a potent natural antioxidant.     

Optimization of the Extraction Process and Antioxidant Activity of Polysaccharide Extracted from Centipeda minima

The purpose of this study is to optimize the extraction process and study antioxidant activity of Polysaccharide extracted from Centipeda minima. The Box-Behnken design-response surface methodology was adopted to optimize the extraction process of polysaccharides from Centipeda minima. We purified the crude polysaccharides from Centipeda minima, as well as determined the purity, monosaccharide composition, and molecular weight of the purified fraction. Fourier transform infrared spectrometer (FT-IR) and scanning electron microscopy (SEM) were used to analyze the structural features of the polysaccharides. Further, we investigated the antioxidant activities of different fractions of polysaccharides. Consequently, the results showed that the optimum extraction conditions for polysaccharides were: a liquid-solid ratio of 26 mL/g, extraction temperature of 85.5 °C, and extraction time of 2.4 h. Moreover, the yield of polysaccharides measured under these conditions was close to the predicted value. After purification, we obtained four components of Centipeda minima polysaccharides (CMP). The purity, monosaccharide composition, molecular weight, and structural characteristics of CMP were different, but with similar infrared absorption spectra. CMP exhibited a typical infrared absorption characteristic of a polysaccharide. Besides, CMP displayed good antioxidant activity, with potential to scavenge DPPH radical, hydroxyl radical, and superoxide radical. Therefore, this study provides a reference for future research on the structure and biological activity of CMP, and lays a theoretical foundation for food processing and medicinal development of CMP.     

Hypoglycemic and hypolipidemic effects and antioxidant activity of fruit extracts from Lycium barbarum

The hypoglycemic and hypolipidemic effects of Lycium barbarum fruit water decoction, crude polysaccharide extracts (crude LBP), and purified polysaccharide fractions (LBP-X) in alloxan-induced diabetic or hyperlipidemic rabbits were investigated through designed sequential trials and by measuring blood glucose and serum lipid parameters. Total antioxidant capacity was also assessed using trolox equivalent antioxidant capacity (TEAC) and oxygen radical absorbance capacity (ORAC) assay. It was found that the three Lycium barbarum fruit extracts/fractions could significantly reduce blood glucose levels and serum total cholesterol (TC) and triglyceride (TG) concentrations and at same time markedly increase high density lipoprotein cholesterol (HDL-c) levels after 10 days treatment in tested rabbits, indicating that there were substantial hypoglycemic and hypolipidemic effects. Hypoglycemic effect of LBP-X was more significant than those of water decoction and crude LBP, but its hypolipidemic effect seemed to be weaker. Total antioxidant capacity assay showed that all three Lycium barbarum extracts/fractions possessed antioxidant activity. However, water and methanolc fruit extracts and crude polysaccharide extracts exhibited stronger antioxidant activity than purified polysaccharide fractions because crude extracts were identified to be rich in antioxidants (e.g., carotenoids, riboflavin, ascorbic acid, thiamine, nicotinic acid). Lycium barbarum polysaccharides (glycocojugates), containing several monosaccharides and 17 amino acids, were major bioactive constituents of hypoglycemic effect. Both polysaccharides and vitamin antioxidants from Lycium barbarum fruits were possible active principles of hypolipidemic effect.     

Purification and Biological Activities of Enzymatically Degraded Sargassum fusiforme Polysaccharides

Enzymatic hydrolysate of the crude polysaccharide (SFP) extracted from Sargassum fusiforme was purified by column DEAE-52 and Sephadex G-100 to yield four components, namely, ESFP1, ESFP2, ESFP3 and ESFP4. These components were characterized by chemical composition assay, GC/MS, HPGPC, UV and FT-IR techniques. The in vitro antioxidant activities of the four purified fractions were investigated by measuring their radical scavenging activity and reducing power. The results suggested that all the four components possess good antioxidant activities. Among them, ESFP1 was found to possess the strongest 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and hydroxyl radical-scavenging activity, and the greatest ferric reducing power. The immunomodulatory effect of these four polysaccharides was demonstrated by their ability to promote proliferation, and to enhance both phagocytic activity and NO release in a macrophage RAW264.7 model. The results revealed that the bioactivities of the polysaccharides are related to their molecular weight, and the uronic acid and sulfate contents.     

平菇菌粗多糖的抗氧化活性研究

采用深层发酵技术生产平菇粗多糖,时其清除DPPH自由基、羟自由基的能力、铁离子螯合能力以及还原力进行了比较分析。结果表明：菌丝体粗多糖和发酵液粗多糖均具有较强的抗氧化能力,但2种多糖的抗氧化能力存在差异;茵丝体粗多糖清除DPPH自由基的能力较强,其EC。。值为2．20mg／mL;发酵液粗多糖清除羟自由基的能力、铁离子螯合能力以及还原力较强,其EC50值分别为0．72mg／mL、3．32mg／mL和7．91mg／mL。在一定的浓度范围内,多糖的浓度增加,其抗氧化能力也随之增强,呈量效依赖关系。     

Study of antioxidant activities of sulfated polysaccharides from Laminaria japonica

The composition, molecular weight and in vitro antioxidant activity of various sulfated polysaccharides obtained by anion exchange chromatography, acid hydrolysis and radical process degradation of the crude sulfated polysaccharide extracted from Laminaria japonica were compared. The low sulfated F-A2, with a peak-molecular weight (Mp) of 5–15 kDa, 14.5% sulfated ester and 21.8% glucuronic acid, exhibited a very strong antioxidant activity on superoxide and hydroxyl radicals, with activity even higher than that of large molecular weight fractions F-A and F-B. However, highly sulfated fractions with a peak-molecular weight below 15 kDa had much lower antioxidant activities than other fractions. These results indicated that the sulfate group of the low molecular weight fractions represents a physical block for the reaction with oxygen radicals. The chemical properties and antioxidant activities of sulfated polysaccharide fractions obtained by radical process degradation of crude sulfated polysaccharide were quite different from those obtained by acid hydrolysates. By radical process degradation, the high molecular weight was decreased to give LM2 (Mp 8 kDa) and LM1 (Mp 1.5 kDa), with a yield of 40% and 15%, respectively. LM2 was enriched with fucose and sulfated ester, while containing low amounts of glucuronic acid. The antioxidant activity showed that LM2 was unable to scavenge either superoxide or hydroxyl radical, which suggested that radical process degradation targeted mainly ascopyllan-like species rich in glucuronic acid, while the fraction rich in sulfated l-fucose remained unchanged. However, LM1 with Mp 1.5 kDa still retained apparent scavenging ability for superoxide radical, although it contained no glucuronic acid and certain amounts of galactose and mannose as main neutral sugars. These result suggest that the antioxidant activity of sulfated polysaccharides is apparently related not only to molecular weight and sulfated ester content, as previously determined, but also to glucuronic acid and fucose content.     

响应面优化塔拉种子多糖的超声波提取及其抗氧化性研究

为获得塔拉多糖超声波提取的最佳工艺,利用中心组合实验设计原理,采用四因素三水平的响应面分析法,获得多元二次线性回归方程,以多糖提取率为响应值做响应面。并考察塔拉多糖的体外抗氧化活性。结果表明：塔拉多糖的最佳提取工艺条件为,超声辅助提取超声功率363 W,超声温度56℃,超声时间23 min,料液比1：17（g·mL^-1）,塔拉粗多糖的最大提取率（25.56%）与理论推测值（25.71%）相差较小。经纯化后塔拉多糖提取率为17.82%。以VC为阳性对照,对不同纯度的塔拉多糖进行抗氧化性的研究,发现其纯度越高,对ABTS自由基的清除能力越强。     

Antioxidant acitivity in vitro and in vivo of the capsule polysaccharides from Streptococcus equi subsp. zooepidemicus

Crude capsule polysaccharides (CCP) were prepared from the culture of Streptococcus equi subsp. zooepidemicus C55129 and were partially purified through an anion-exchange column chromatography to afford partially purified capsule polysaccharides (PCP). The main component of CCP and PCP was hyaluronic acid. In vitro antioxidant assay, the capsule polysaccharides showed strong inhibition of lipid peroxidation and hydroxyl radical scavenging activity and moderate 1,1-diphenyl-2-picryldydrazyl radical scavenging activity. In addition, CCP exhibited much stronger reductive power than PCP. For antioxidant testing in vivo, CCP and PCP were orally administrated over a period of 15 days in a d-galactose induced aged mice model. As results, administration of capsule polysaccharides inhibited significantly the formation of malondialdehyde in mice livers and serums and raised the activities of antioxidant enzymes and total antioxidant capacity in a dose-dependent manner. However, the antioxidant activity of CCP was lower than that of PCP. The results suggest that the capsule polysaccharides from Streptococcus equi subsp. zooepidemicus C55129 have direct and potent antioxidant activities.     

Efficient purification of antiproliferative polysaccharides from Hypsizigus marmoreus with radial flow chromatography

The increasing commercial significance of natural polysaccharides for use in medicinal products is stimulating the development of efficient and easy scale‐up techniques for polysaccharide purification. In this research, the crude polysaccharides from submerged cultivation broth of Hypsizigus marmoreus were purified using radial flow chromatography (RFC), and the antiproliferative activity of the purified fractions was evaluated in vitro. DEAE Sepharose CL‐6B was selected to be packed in the RFC column based on its good resolution, physical stability, and low cost. Compared with axial flow chromatography (AFC), an efficient chromatographic process with significantly less time and buffer consumption but yielding higher polysaccharide recovery and resolution was established in RFC, which could clearly purify the crude polysaccharides into different fractions. An acceptable linear scale‐up effect of RFC from 100 to 500 mL was successfully achieved without loss of resolution and enhancement of time consumption. 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assays in cell cultures indicated that the purified polysaccharide fractions possess moderate antiproliferative activities in three different human cancer cell lines, but have significantly lower cytotoxicity in normal human cell lines in vitro. Among the polysaccharide fractions, the main purified acidic fraction W‐I could be considered as a novel potential antitumor agent candidate for several tumors, especially for human alveolar epithelial tumors. This research confirmed for the first time that RFC would be a new fast and efficient tool for purification of polysaccharides into different fractions, both at laboratory and commercial scales. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:872–878, 2014     

Identification of polysaccharides from pericarp tissues of litchi (Litchi chinensis Sonn.) fruit in relation to their antioxidant activities

A large number of polysaccharides are present in the pericarp tissues of harvested litchi fruits. A DEAE Sepharose fast-flow anion-exchange column and a Sephadex G-50 gel-permeation column were used to isolate and purify the major polysaccharides from litchi fruit pericarp tissues. Antioxidant activities of these major polysaccharide components were also evaluated. An aqueous extract of the polysaccharides from litchi fruit pericarp tissues was chromatographed on a DEAE anion-exchange column to yield two fractions. The largest amount of the polysaccharide fraction was subjected to further purification by gel filtration on Sephadex G-50. The purified product was a neutral polysaccharide, with a molecular weight of 14 kDa, comprised mainly of 65.6% mannose, 33.0% galactose and 1.4% arabinose. Analysis by Smith degradation indicated that there were 8.7% of (1-->2)-glycosidic linkages, 83.3% of (1-->3)-glycosidic linkages and 8.0% of (1-->6)-glycosidic linkages in the polysaccharide. Furthermore, different polysaccharide fractions extracted and purified from litchi fruit pericarp tissues exhibited strong antioxidant activities. Among these fractions, the purified polysaccharide had the highest antioxidant activity and should be explored as a novel potential antioxidant.     

发酵天山雪莲粗多糖的菌株筛选及护肤功效研究

【目的】利用微生物发酵植物可以提高多糖的产量,并且能够将原有的植物多糖转化成活性更高的新型发酵多糖,本研究围绕天山雪莲的粗多糖,基于发酵后的活菌数、多糖产量和护肤功效进行发酵菌种筛选,旨在获得适宜发酵天山雪莲粗多糖的优良菌株。【方法】利用不同菌株发酵天山雪莲粗多糖,通过平板菌落计数法测定活菌数,采用蒽酮比色法测定发酵液的多糖含量;采用细胞屏障损伤和抗炎模型,利用噻唑蓝(MTT)法检测细胞活率,利用格里斯法检测NO含量,评价发酵多糖在细胞模型中的护肤功效;利用特应性皮炎小鼠模型,分析发酵多糖对皮肤组织表观及经皮失水率、皮肤组织病理及表皮厚度变化和皮肤组织屏障蛋白-丝聚合蛋白的影响,评价发酵多糖在动物模型中的功效。【结果】不同菌株发酵天山雪莲粗多糖后的活菌数和多糖产量差异较大,其中枯草芽孢杆菌(Bacillus subtilis) CCFM1162和165-M1、干酪乳杆菌(Lactobacillus casei) CCFM1073、罗伊氏乳杆菌(L. reuteri) CCFM8631、清酒乳杆菌(L. sakei) GD17-9的活菌数较高,均不低于2.0×108 CFU/mL;而酿酒...     

Chemical characters and antioxidative properties of sulfated polysaccharides from Laminaria japonica

A low molecular weight sulfated polysaccharide (L-A) was prepared bymild acid hydrolysis of crude fucoidan (F-A) from Laminaria japonica. In comparison with F-A, L-A had a lower proportion of fucose residues,but a similar proportion of sulfate. The galactose content of both fractionswas relatively high, especially for L-A (57%). The antioxidant propertiesof the two polysaccharides were studied using two low-density lipoproteinoxidation systems. L-A had a stronger effect against low-density lipoproteinoxidation in both systems. F-A inhibited the AAPH-induced low-densitylipoprotein oxidation, but had little effect on the Cu⁺⁺-inducedsystem due to its large molecular mass. The active sulfated fraction L-A,containing galactose, mannose and fucose (about 9: 2: 2) is reported herefor the first time.     

Purification, structure and immunobiological activity of an arabinan-rich pectic polysaccharide from the cell walls of Prunus dulcis seeds

The structure and bioactivity of a polysaccharide extracted and purified from a 4M KOH + H3BO3 solution from Prunus dulcis seed cell wall material was studied. Anion-exchange chromatography of the crude extract yielded two sugar-rich fractions: one neutral (A), the other acidic (E). These fractions contain a very similar monosaccharide composition: 5:2:1 for arabinose, uronic acids and xylose, respectively, rhamnose and galactose being present in smaller amounts. As estimated by size-exclusion chromatography, the acidic fraction had an apparent molecular mass of 762 kDa. Methylation analysis (from the crude and fractions A and E), suggests that the polysaccharide is an arabinan-rich pectin. In all cases, the polysaccharides bear the same type of structural Ara moieties with highly branched arabinan-rich pectic polysaccharides. The average relative proportions of the arabinosyl linkages is 3:2:1:1 for T-Araf:(1-->5)-Araf:(1-->3,5)-Araf:(1-->2,3,5)-Araf. The crude polysaccharide extract and fractions A and E induced a murine lymphocyte stimulatory effect, as evaluated by the in vitro and in vivo expression of lymphocyte activation markers and spleen mononuclear cells culture proliferation. The lymphocyte stimulatory effect was stronger on B- than on T-cells. No evidence of cytotoxic effects induced by the polysaccharide fractions was found.     

雪松松针多糖超声波酶法提取及其抗氧化性

为优化雪松松针多糖超声波酶法的提取工艺,并研究多糖结构及其抗氧化性。通过响应面法分析确定最佳提取参数为:3. 0 g松针粉末,液料比20∶1(m L∶g),提取温度80℃,超声功率560 W,超声时间47 min,纤维素酶用量12 FPU/g原料,提取两次,多糖得率高达10. 39%。采用高效液相色谱、红外光谱和核磁共振光谱等对松针多糖进行了结构表征,松针多糖以β-糖苷键为主要连接方式,并由葡萄糖、果糖、阿拉伯糖和半乳糖等单糖组成。体外抗氧化性研究结果表明:松针粗多糖对羟基自由基(·OH)和1,1-二苯基-2-三硝基苯肼自由基(DPPH·)的清除能力远高于纯化多糖,呈现出良好的量效关系,粗多糖对·OH和DPPH·的半抑制浓度IC50分别为0. 47 g/L和0. 076 g/L。     

Comparison of the primary structures of clathrin light chains from bovine brain and adrenal gland by peptide mapping

The structures of the polymorphic forms of clathrin light chains were analyzed by two peptide mapping procedures. Comparison of the products of partial digestion by V8 protease showed no common peptides between LCA and LCB from bovine brain. No similarities between clathrin light chains and tropomyosin chains from bovine brain and skeletal muscle were detected with this technique. The peptides produced by complete tryptic digestion of LCA and LCB from bovine brain and bovine adrenal gland were analyzed by reverse phase h.p.l.c. For both LCA and LCB the polypeptides from different tissues showed considerable homology. LCA from brain and adrenal gland shared 10 out of a total of 15 peptides. LCB from brain and adrenal gland shared 10 out of 14 peptides. In contrast, when LCA was compared with the LCB chain from the same tissue very few peptides were shared; 4/23 for brain and 3/21 for adrenal gland. These results strongly indicate that, within a tissue, LCB is not related to LCA by post-translational processing and that each chain is encoded by a separate gene. The data also demonstrate the close homology of the different forms of LCA and LCB expressed in different tissues within the same organism. Thus the polymorphic differences of clathrin light chains within a tissue are greater than those between tissues.     

Crude polysaccharide from an anti-UVB cell clone of <Emphasis Type="Italic">Bupleurum scorzonerifolium</Emphasis> protect HaCaT cells against UVB-induced oxidative stress

Bupleurum scorzonerifolium Willd has been found to have a wide range of immunopharmacologic functions. We isolated an anti-UVB B. scorzonerifolium cell clone and found elevated level of polysaccharides. In this study, we investigated the ability of crude polysaccharide (CP) from the anti-UVB B. scorzonerifolium cell clone to inhibit UVB-induced photodamage using a human skin keratinocyte cell line, HaCaT. Cells were UVB irradiated and then incubated in presence of different concentrations of CP. MTT assay showed that the CP did not induce cytotoxic effect under 10 mg/mL and after UVB irradiation, CP can inhibit UVB-induced HaCaT cell death. Decreased reactive oxygen species and lipid peroxidation and increased superoxide dismutase activity showed that CP can act as a free radical scavenger. Furthermore, CP had a strong protective ability against UVB-induced DNA damage. These effects were compared to the crude polysaccharide (CP′) from normal B. scorzonerifolium callus at concentration of 20 mg/mL. The portion of crude polysaccharide (CP) from the anti-UVB B. scorzonerifolium cell clone was more than 2.5-fold higher than crude polysaccharide (CP′) from normal B. scorzonerifolium callus. Taken together, the protective mechanisms of crude polysaccharide from the anti-UVB B. scorzonerifolium cell clone against UVB-induced photodamage occur by the inhibition of UVB-induced reactive oxygen species production, lipid peroxidation and DNA damage.     

Antioxidant activity of a water-soluble polysaccharide purified from Pteridium aquilinum

A water-soluble crude polysaccharide, obtained from fern Pteridium aquilinum, was fractionated by DEAE-Sepharose Fast-Flow column chromatography, and purified by Sephacryl S-400 HR column chromatography. The average molecular weight (M_w) of the purified polysaccharide (PLP) is 458,000 Da. The monosaccharide components of PLP were characterized by gas chromatography (GC), and the majority of the monosaccharide components was glucose (relative mass 58.1%) with low levels of galactose, mannose, rhamnose, and arabinose (relative mass 18.7%, 6.8%, 10.2%, and 6.1%, respectively). The Fourier-transform infrared spectra (FTIR) of PLP revealed typical characteristics of polysaccharides. On the basis of the ferric-reducing antioxidant power assay (FRAP), DPPH radical-scavenging, the superoxide radical assay, and self-oxidation of 1,2,3-phentriol assay, the antioxidant activities of PLP were investigated. The purified polysaccharide was demonstrated to have strong reductive power (FRAP value: 827.6 μmol/L), moderate scavenging activities against DPPH radicals (83.1%) and superoxide radicals (60.5%), and moderate inhibiting power for self-oxidation of 1,2,3-phentriol (52.4%).     

宁夏不同地区灵武长枣果实多糖的单糖成分分析

以宁夏4个不同地区(灵武、中宁、青铜峡、银川)成熟期的灵武长枣果实为研究对象,经水提醇沉法提取,采用DEAE-cellulose52和HW-55S分离纯化,并利用GC-MS法进行多糖的单糖组成分析。结果表明:多糖提取率最高的是灵武地区,达到1.795%;分离纯化后,4个地区的长枣多糖各得到1个中性(Ju-0)和3个酸性组分(Ju-1、Ju-2、Ju-3),其中Ju-2含量最高;GC-MS分析可知灵武长枣多糖含有阿拉伯糖、鼠李糖、核糖、岩藻糖、木糖、甘露糖、半乳糖、葡萄糖、葡萄糖醛酸、半乳糖醛酸10种单糖,不含果糖,以阿拉伯糖、核糖、半乳糖和2种糖醛酸为主,木糖含量最低。各地区多糖的单糖组成、含量各不相同,从各组分来看,四个地区多糖的Ju-0和Ju-1组分组成均以阿拉伯糖、核糖、半乳糖为主,四个地区多糖的组成差异主要在于Ju-2和Ju-3组分。从各地区单糖总量来看,灵武地区是阿拉伯糖含量最高,中宁、青铜峡、银川地区以葡萄糖醛酸含量为最高。     

奶油栓孔菌菌丝体多糖的提取工艺优化、结构表征及抗氧化活性

奶油栓孔菌Trametes lactinea是一种生物活性丰富的大型真菌。本研究在单因素试验的基础上,通过响应面法优化其菌丝体多糖的提取工艺,利用DEAE-Cellulose-52阴离子交换柱和Sephadex G-200层析柱对粗多糖进行分离纯化,获得TLMPS-0、TLMPS-1和TLMPS-3均一多糖组分。采用化学组成分析、UV-vis、FTIR、刚果红实验对3种多糖组分进行结构分析,并检测了多糖清除自由基的能力和还原力。结果表明,奶油栓孔菌菌丝体多糖最优提取工艺为：提取温度99℃、料液比1:30 (g/mL)、提取时间5h,提取次数2次。在此工艺条件下,多糖提取率为4.01%。TLMPS-0、TLMPS-1和TLMPS-3的糖醛酸含量分别为12.91%±0.44%、8.24%±0.22%、7.50%±0.66%,硫酸基含量分别为22.24%±1.88%、14.55%±0.56%、18.68%±0.69%,并且证明TLMPS-0是一种α-吡喃型多糖或β-吡喃型多糖,而TLMPS-1是一种β-吡喃型多糖,均不具备三螺旋空间构象,此外,3种多糖组分均具有一定的清除DPPH自由基、ABTS自由基、羟基自由基的能力和铁离子还原能力,其中TLMPS-0抗氧化活性最强。研究结果为奶油栓孔菌多糖的功能研究与挖掘提供了研究基础与理论依据。     

Antiviral Effects of Sulfated Exopolysaccharide from the Marine Microalga <Emphasis Type="Italic">Gyrodinium impudicum</Emphasis> Strain KG03

The sulfated exopolysaccharide p-KG03, which is produced by the marine microalga Gyrodinium impudicum strain KG03, exhibited impressive antiviral activity in vitro (EC₅₀ = 26.9 µg/ml) against the encephalomyocarditis virus (EMCV). Depending on the p-KG03 concentration, the development of cytopathic effects in EMCV-infected HeLa cells was either inhibited completely or slowed. Moreover, p-KG03 did not show any cytotoxic effects on HeLa cells, even at concentrations up to 1000 µg/ml. The polysaccharide was purified by repeated precipitation in ethanol, followed by gel filtration. The p-KG03 polysaccharide had a molecular weight of 1.87 × 10⁷, and was characterized as a homopolysaccharide of galactose with uronic acid (2.96% wt/wt) and sulfate groups (10.32% wt/wt). The biological activities of p-KG03 suggest that sulfated metabolites from marine organisms are a rich source of antiviral agents. This is the first reported marine source of antiviral sulfated polysaccharides against EMCV. The p-KG03 polysaccharide may be useful in the development of marine bioactive exopolysaccharide for biotechnological and pharmaceutical products.