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1.
高效阴离子交换色谱法测定毛头鬼伞多糖中的单糖组成 总被引:2,自引:0,他引:2
本文采用高效阴离子交换色谱—脉冲安培检测器(HAPEC-PAD),建立了一种测定多糖中单糖比例的方法。以NaOH为淋洗液、CarboPac^TM A20预处理柱,CarboPac^TMPA20分离柱,金工作电极,Ag/AgCl参比电极,8种自然界中常见单糖标准品做混合标样,探索方法可行性。在淋洗液浓度为2.5mmol/L时,各种单糖组分得到有效分离,其线性和重现性均良好并在此基础上测定了毛头鬼伞多糖中单糖比例;与传统的方法相比,此方法具有前处理简单、灵敏度高、节省时间和试剂等优点。 相似文献
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桦褐孔菌多糖的体外抗氧化作用研究 总被引:6,自引:2,他引:6
Inonotus obliquusis placed in theBasidiomycotina, Hymenomycetes , Aphyllophoralesand Polyporaceae[1]. The mushroomis a wood-decaying fungus that grows under the bark oflive standing trees such as birch, el m andJapanese alder , or on the dry trunks of thesetrees after felling . In Russian folklore ,I .obliquusis considered a medicinal fungus andhas been widely used to prevent and treatdiseases and tumors affecting the digestivesystem ( e . g . gastric , intestinal and livercancers ) , cardio… 相似文献
3.
不同基因型龙眼果实中多糖含量的比较 总被引:12,自引:0,他引:12
用苯酚-硫酸法测定国家果树种质福州龙眼圃中不同基因型的84份龙眼果实和龙眼育种园内85份不同基因型龙眼杂交后代果实多糖含量。结果表明,不同基因型龙眼果实中多糖含量平均为239.66mg/100g;含量最高的是桂花味,为578.73mg/100g;其次是先锋黄肉,为496.05mg/100g;最低的是赐合种,为95.85mg/100g;含量最高的是平均含量的2.41倍,是最低含量的6.04倍。不同基因型龙眼后代中多糖含量平均为248.15mg/100g;其中最高的是96-046,为811.77mg/100g;其次是96-058,为493.25mg/100g;最低的是96-059,为73.08mg/100g;含量最高的是平均的3.27倍,是最低的11.11倍,是亲本平均含量的2.52倍。多糖含量较高的父母本,经有性杂交,通过基因重组后代出现超亲个体。 相似文献
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Isolation, purification and identification of polysaccharides from cultured Cordyceps militaris 总被引:8,自引:0,他引:8
Four polysaccharides from the water extract of cultured Cordyceps militaris were isolated through ethanol precipitation, deproteination and gel-filtration chromatography. Their molecular weights were determined using gel-filtration chromatography. Among the four isolated polysaccharides, the structures of two of them (CPS-2 and CPS-3) were elucidated by sugar analysis, Smith degradation, IR and (13)C-NMR spectroscopy. 相似文献
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本研究从商陆根部提取分离出商陆多糖,并对该多糖含量进行测定及体外抗氧化活性研究。商陆根部经石油醚回流脱脂、热水抽提、脱色、乙醇沉淀等处理可从中提取出粗多糖。多糖经三氯乙酸脱蛋白纯化,再分别以考马斯亮蓝法和蒽酮-硫酸法测定其蛋白质含量和糖含量,并通过采用清除羟自由基和超氧自由基能力测定法、β-胡萝卜素-亚油酸法,以抗坏血酸(Vc)为对照,来分析粗多糖和纯多糖的体外抗氧化能力。采用水提法提取的粗多糖,含有10.69%的蛋白质和60.91%的多糖;纯化后的多糖糖含量达到91.04%。商陆粗多糖、纯多糖及Vc对羟自由基(·OH)清除率的IC50分别是1.26mg/mL、4.78mg/mL和0.224mg/mL;对超氧自由基(O2-·)清除率的IC50分别为1.91mg/mL、2.28mg/mL和0.123mg/mL;对β-胡萝卜素-亚油酸体系的抑制作用的IC50分别为0.471mg/mL、0.692mg/mL和0.379mg/mL。实验结果表明商陆多糖是一种较好的抗氧化剂,可作为潜在天然抗氧化剂应用于食品和医药工业中。 相似文献
8.
We investigated the polysaccharide composition of bulk and mineral-bound (density fractions >2 g cm−3) organic matter in topsoil and subsoil horizons of a Podzol and a Cambisol. Total sugar contents were generally higher in the Cambisol than in the Podzol. For most horizons of both soils, the sugars were enriched in the mineral-bound organic matter fraction. This fraction showed a monosaccharide distribution typical for microbial sugars, whereas in bulk soil horizons higher contributions of plant-derived sugars were observed. A strong relationship with the 14C activity of the dense fraction suggests that microbial-derived polysaccharides are most likely stabilised preferentially by mineral interactions compared to plant-derived polysaccharides. 相似文献
9.
JIN Li-qin LU Jian-xin YU Kang YUAN Qian XIE Ke-jian WANG Kai-fa ZHANG Yu-lan 《园艺学报》2000,16(8):726-729
AIM: To study the activation effects of maize pollen polysaccharides(PPM) on human thoracic cavity macrophage (hTMΦ). METHODS: Activities of lactate dehydrogenase(LDH) and acid phosphatase (ACP) in the hTMΦ were detected by automatic biochemical analyzer, and the level of tumor necrosis factor alpha(TNF-α) and interleukin-6(IL-6) in the hTMΦ was analyzed by radioimmunoassay, after hTMΦ were cultured with 0.312, 0.625, 1.250, 2.500, 5.000 mg/mL PPM-RPMI 1640 for 24 and 48 hours in vitro. RESULTS: The activities of LDH and ACP increased in the hTMΦ induced by PPM, and the levels of TNF-α and IL-6 in the hTMΦ induced by PPM increased markedly too. And the induced expression effect of TNF-α and IL-6 is associated with the concentration of PPM, and time for PPM inducing. CONCLUSION: PPM can induce cytokines secretion in hTMΦ, and activate hTMΦ in vitro. 相似文献
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