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Preparation and characterization of agar,agarose,and agaropectin from the red alga Ahnfeltia plicata
Agar,agarose,and agaropectin were extracted from the red alga Ahnfeltia plicata,and their properties and structures were characterized.Agar was extracted by a comparatively low alkaline consumption of 1.2%.It exhibited a gel strength of 1 152.50±74.25 g/cm^2 and a sulfate content of 0.55%±0.08%.The yield of agar from A.plicata was 24.53%,which is higher than those of other agarophytes commonly used in China.Three kinds of the method were compared for the purification of agarose,and the physicochemical properties of agarose that was prepared under the optimal condition were identical to those of commercially available agarose.Furthermore,agaropectin was purified from A.plicata and characterized by GC,HPLC,UV-spectrum,and FI-IR to understand its composition and structure.It was the first time to comprehensively study the agar and its fractions from the red alga of A.plicata.This research provided an eco-friendly agar extraction method from A.plicata and revealed its potential application for the production of agar,agarose,and agaropectin. 相似文献
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南、北方坛紫菜多糖结构特征的比较研究 总被引：5，自引：1，他引：5
对南方产(1987年3月采)和移植北方养殖(1988年11月采)的两种坛紫菜的热水和冷水提取多糖进行了层析分级,用~(13)C-NMR和IR光谱研究了各级分的化学结构特征,结果表明,南北方坛紫菜多糖分别主要由用 1.0mol/L和0.5mol/L NaCl从DEAE—Sephadex A_(50)层析柱洗脱下的带电荷的琼胶糖分子组成;~(13)C-NMR谱图表明坛紫菜主要由琼胶糖结构及其生物前体(硫酸基结合在L-半乳糖的第6位碳上)构成,且甲基化琼胶糖在南方坛紫菜中的含量明显比北移坛紫菜高,这是坛紫菜由南方移植北方后的明显差异。 相似文献
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The structural feature of agar polysaccharides from Porphyra haitanensis grown in south China and transplanted to the north was investigated by fractioriation on DEAE - Sephadex A 50, chemical analysis, and infrared and 13C - NMR spectroscopy.The agars composed mainly of Charged molecules were eluted from DEAE - Sephadex A 50 with 1.0 mol/L- NaCl solution from the southern P. haitanensis and with 0.5 mol/L NaCl from the northern one. The 13C-NMR spectra showed that agarobiose [(1 -3)- B D - galactopyranosyl - (1 -4)-3,6-anhydro-a-L-galactopyranose] and the biological precursor of agarobiose [(1-3} B-D-galactopyra nosyl- (1-4)- 6- sulfate-a- L-galactopyranose ] were the major disaccharide repeating units in the charged fractions. The content of the biological precur sor in the agar polysaccharides from southern P. haitanensis was higher than that in the northern one, the content of the biological precursor extracted from cold water was higher than that from hot water, and the content of 6- OMe-D-galactos 相似文献
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海洋弧菌HN897株是一株高产琼脂糖酶的Vibrio astriarenae菌, 前期功能缺失实验证明其β-琼脂糖酶基因vas1-1339的缺失可显著降低弧菌HN897株的琼脂水解活性。文章在大肠杆菌中异源表达Vas1-1339基因编码蛋白, 分析该基因的表达及蛋白功能活性。首先, 构建含vas1-1339基因开放阅读框全长的表达载体pET28a-1339, 利用原核表达技术在大肠杆菌中成功地异源表达了Vas1-1339琼脂糖酶; 然后, 利用卢戈氏碘液染色分析发现异源表达Vas1-1339琼脂糖酶的大肠杆菌能够高效水解琼脂, 且异丙基硫代半乳糖苷(IPTG)最优诱导浓度为10μmol·L-1; 免疫印迹分析发现胞内基因表达产物羧基端可能存在切割现象, 推测Vas1-1339琼脂糖酶存在复杂的成熟过程。对纯化的琼脂糖酶活性分析发现海洋弧菌HN897株β-琼脂糖酶Vas1-1339能够独立发挥琼脂糖降解功能。 相似文献
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Studies on Gelidium amansii agar fractionations were carried out in this paper. Gelidium amansii agar was fractionated on DEAE-Cellulose, and four fractions were obtained sequentially. The fractions were analyzed on physical and chemical properties, and IR and 13C-NMR spectroscopy applied for elucidating the chemical structure. Among the four fractions obtained, water fraction measured up to the standard of low EEO agarose. The sulfate content, ash content, electroendosmosis and gel strength (1%) of water fraction were 0.16%, 0.34%, 0.12 and 1 130g/cm2 respectively, similar to those of the Sigma products. 相似文献
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The structural feature of agar polysaccharides fromPorphyra haitanensis grown in south China and transplanted to the north was investigated by fractionation on DEAE—Sephadex A 50, chemical analysis,
and infrared and13C-NMR spectroscopy. The agars composed mainly of charged molecules were eluted from DEAE—Sephadex A 50 with 1.0 mol/L NaCl
solution from the southernP. haitanensis and with 0.5 mol/L NaCl from the northern one. The13C-NMR spectra showed that agarobiose [(1→3)-β-D-galactopyranosyl-(1→4)-3,6-anhydro-α-L-galactopyranose] and the biological precursor of agarobiose [(1→3)-β-D-galactopyra nosyl-(1→4)-6-sulfate-α-L-galactopyranose] were the major disaccharide repeating units in the charged fractions. The content of the biological precursor
in the agar polysaccharides from southernP. haitanensis was higher than that in the northern one, the content of the biological precursor extracted from cold water was higher than
that from hot water, and the content of 6-OMe-D-galactose in the southernP. haitanensis polysaccharides was higher than in the northern one. This distinct difference will be of significance for further study of
the physiological characters ofP. haitanensis.
Contribution No. 1849 from the Institute of Oceanology, Academia Sinica. 相似文献
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王铭和 《广东海洋大学学报》1994,(1)
根据对ＳＩＧＭＡ公司１９９２年产品目录中琼胶和琼胶糖的技术数据进行比较分析的结果认为，可以利用灰分或硫酸根含量这一主要数据作为指标，把它们划分为三个不同的质量等级，即琼胶（灰分３～６％）、纯化琼胶（灰分≤２．０％）和琼胶糖（硫酸根≤０．２０％～≤０．３５％） 相似文献
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琼脂糖是一种具有高凝胶特性的天然高分子红藻多糖,具有良好的物理、化学和热稳定性,在医学和科研方面具有广泛的用途。在琼脂糖制备工业中,传统生产技术的局限性造成了国内琼脂糖尚未规模化生产。因此,有必要开发新的成本可控的琼脂糖制备方法。本文采用一种聚丙烯酰胺和弱碱性苯丙烯系阴离子交换树脂联用的方法来分离制备琼脂糖,以江蓠琼胶为原料,通过单因素试验优化琼脂糖的制备参数并对琼脂糖的理化指标进行测定。所得琼脂糖硫酸根含量为0.22%、凝胶强度为1 524 g/cm2、透明度为58.9%,凝固温度为39.7℃、融化温度为87.6℃,表明其具有相对较高的质量。该工艺简单经济,对发展琼脂糖工业具有一定的参考价值。 相似文献