蒲公英多糖脱色脱蛋白方法及其降血糖活性研究

以蒲公英为原料,采用超声波辅助法提取蒲公英粗多糖,对其脱色和脱蛋白工艺进行研究,并评价纯化前后多糖的体外降血糖能力。以脱色率和多糖损失率为考察指标,对大孔树脂、活性碳、过氧化氢、壳聚糖的脱色效果进行对比,筛选出最佳的脱色方法;以脱蛋白率和多糖损失率为考察指标,对Sevag法、盐析法、酶-三氯乙酸(trichloroacetic acid,TCA)法、酶-Sevag法的脱蛋白效果进行比较,筛选出最优的脱蛋白方法;利用抑制α-葡萄糖苷酶能力评价多糖的体外降血糖活性。结果表明:大孔树脂S-8脱色效果最优,色素脱除率为86.45%,多糖损失率为18.9%;盐析法脱蛋白效果最优,蛋白质脱除率为85.64%,多糖损失率为20.51%。所得精制多糖对α-葡萄糖苷酶有一定的抑制能力,随着多糖质量浓度的增加,抑制率逐渐增大,当质量浓度为1.0 mg/mL时,抑制率达到76.28%。     

黑虎掌菌多糖脱色工艺及其抗氧化活性

为研究黑虎掌菌多糖的脱色工艺及其抗氧化活性,以脱色率和多糖保留率为指标,评价不同类型树脂的脱色效果,并通过单因素试验和正交试验优化树脂法脱色的工艺条件。采用总抗氧化能力测定法评价脱色前后多糖样品的抗氧化活性。结果表明:D202的脱色效果较好,其优化工艺条件为:温度60℃、树脂加入量10 g/100 mL、多糖溶液pH 9.00、多糖质量浓度4.0 mg/mL、时间3 h,此条件下的多糖脱色率为91.75%±0.70%,多糖保留率为55.84%±6.64%。该法的脱色效果优于活性炭法和过氧化氢法。脱色前后多糖的抗氧化性能变化不大。故树脂法对黑虎掌菌多糖的脱色效果较好。     

黔产多汁乳菇多糖脱色工艺及抗氧化活性研究

研究多汁乳菇多糖的脱色工艺及抗氧化活性。以脱色率和多糖保留率为指标,评价不同类型树脂的脱色效果,并通过单因素试验和正交试验优化树脂法脱色的工艺条件。采用总抗氧化能力测定法评价脱色前后多糖样品的抗氧化活性。结果表明, D 202的脱色效果较好,其优化工艺条件为:温度60℃,树脂加入量15 g/100 mL,多糖质量浓度2 mg/mL,时间3 h。此条件下的多糖脱色率为95.25%±0.10%,多糖保留率为48.65%±0.28%。该法的脱色效果优于活性炭法和过氧化氢法。脱色前后多糖的抗氧化性能变化不大。树脂法对多汁乳菇多糖的脱色效果较好。     

羊肚菌多糖抑制人乳腺癌细胞MDA-MB-231增殖和诱导细胞凋亡研究

以黑脉羊肚菌多糖为原料,研究羊肚菌多糖对人乳腺癌细胞MDA-MB-231（以下简称MDA）增殖和凋亡的影响。结果表明：在无细胞毒性范围内,羊肚菌多糖能显著抑制人乳腺癌细胞MDA的增殖,半数有效浓度（median effective concentration,EC50）值为0.096 mg/mL,同时人乳腺癌细胞MDA表现出多种细胞凋亡的形态学变化。免疫印迹检测实验结果显示,羊肚菌多糖能抑制B淋巴细胞瘤-2（B-cell lymphoma-2,Bcl-2）蛋白表达,促进Bcl-2相关X蛋白（Bcl-2 associated X protein,Bax）表达,同时增加Bax/Bcl-2蛋白表达比值,并呈现出剂量依赖效应。说明羊肚菌多糖能抑制人乳腺癌细胞MDA增殖,促进细胞凋亡。     

薯蔓多糖的纯化工艺

采用活性炭脱色,选取时间、温度、活性炭用量3个因素进行正交实验,用脱色率和多糖含量作为考察指标。采用三氯乙酸法和Sevage法去除蛋白质,主要研究其浓度与体积比对蛋白质去除率和多糖损失率的影响。结果表明：40℃、40min、活性炭用量为1．0％时去除色素效果最好,脱色率为21．98％,多糖保留率为94．09％。薯蔓多糖溶液与5％TCA溶液体积比为1：2时,去除蛋白质效果较好;Sevage（氯仿：正丁醇=4：1）溶液与薯蔓多糖溶液体积比为1：1时,去除蛋白质效果较好。     

木瓜多糖的冷电弧-光催化-吸附脱色工艺研究

以钛酸四丁酯为钛源,采用溶胶法制备FeSO4掺杂的光催化剂TiO2,并将光催化剂负载于活性炭,然后将活性炭填装于冷电弧-光催化-吸附集成装置中,用该装置对木瓜多糖进行脱色。以木瓜多糖的脱色率和糖保留率为指标,研究脱色时间、加载电压、活性炭填充率及木瓜多糖初始质量浓度4个因素对指标的影响。在单因素试验的基础上,利用二次回归正交旋转组合设计优化木瓜多糖的冷电弧-光催化-吸附脱色工艺,建立回归模型并确定最佳脱色工艺条件。结果表明,在脱色时间22.7min、电压24.0kV、活性炭填充率41.4%及木瓜多糖质量浓度3.7mg/mL条件下,脱色率和多糖保留率分别达为73.2%和76.6%。     

灰树花胞外粗多糖脱色工艺优化及对α-葡萄糖苷酶抑制作用的影响

该研究以灰树花（Griflola frondosa）胞外粗多糖为原料,以多糖脱色率和保留率为评价指标,用静态吸附法从8种不同树脂中 优选出脱色效果最佳的树脂,并对其脱色工艺参数进行单因素试验和正交试验优化,最后考察脱色前后多糖对α-葡萄糖苷酶抑制的 影响。 结果表明,脱色效果最佳的树脂为D315,其对灰树花胞外粗多糖脱色的最佳工艺参数为脱色温度55 ℃、脱色时间420 min、脱 色pH 5.0、粗多糖质量浓度10 mg/mL。 在此最优条件下,灰树花胞外粗多糖的脱色率为90.61%,多糖保留率为78.23%,较优化前分别 提高2.78%、4.12%。 经树脂D315处理后的灰树花胞外粗多糖对α-葡萄糖苷酶抑制作用显著提高（P＜0.05）。     

茯苓渣多糖组成分析及体外抗癌、免疫活性研究

目的:以茯苓渣为原料，通过热水浸提茯苓多糖，研究其单糖组成及抗癌、抗炎症因子及免疫活性，为开发茯苓多糖相关产品提供了理论依据。方法:利用高效液相色谱和红外光谱对水提茯苓多糖进行单糖组成分析，采用CCK-8法对水提茯苓多糖进行抗肿瘤及免疫活性研究。结果:水提茯苓多糖的多糖含量为76%，具有明显的多糖特征吸收峰，主要由葡萄糖、甘露糖、半乳糖、岩藻糖组成，其物质的量之比为1:0.107:0.079:0.018；对胃癌细胞、乳腺癌细胞、肝癌细胞均有抑制作用，对胃癌细胞的增殖抑制效果最优（IC₅₀=1096 μg/mL），对小鼠脾淋巴细胞具有促进增殖作用。结论:水提茯苓多糖具有良好的体外抗癌及免疫活性。     

巴西蘑菇发酵菌丝体醇提物的抑瘤活性

巴西蘑菇深层发酵的菌丝体，用热水提取出水溶性成分（主要是活性多糖）后，残渣用体积分数859，6的乙醇提取，对乙醇提取物进行了抑瘤活性的研究。体外细胞培养实验表明，菌丝体醇提物对人肝癌细胞Bel-7402有一定抑制作用，半抑制浓度（IC50）为1507μg／mL：体内则显示出了较强的抑瘤效果，腹腔注射（i．p．）每天10、50、100mg／kg，对S180荷瘤鼠的瘤重抑制率分别为44．72％、66．50％和70．49％；灌胃（p．o．）每天800mg／kg，对S180腹水瘤鼠的生命延长率达到52．94％。结果表明：巴西蘑菇深层发酵菌丝体的醇提物具有较强的抑瘤作用，其具体的功效成分值得进一步研究。     

发芽糙米中粗多糖的纯化及分子量测定

本文对发芽糙米粗多糖进行纯化,通过比较活性炭吸附法、过氧化氢氧化法、大孔树脂吸附法三种方法的脱色效果,以及Sevage法、三氯乙酸法、酶与Sevage结合方法三种方法的脱蛋白效果,筛选出发芽糙米粗多糖脱色、脱蛋白的最佳方法。分别比较了DEAE-Sepharose CL-6B、DEAE Fast Flow、DEAE Sepharose 52三种柱层析填料对糙米粗多糖的层析纯化效果,筛选出最优填料。并对纯化后的发芽糙米多糖各组分进行分子量的测定。结果表明:大孔树脂AB-8对发芽糙米粗多糖脱色效果最佳,脱色率为86.57%,多糖损失率为28.96%。酶-Sevage法脱蛋白效果较好,且多糖损失率低,脱蛋白率为74.36%,多糖损失率为14.09%。对发芽糙米多糖进行柱层析的最佳填料为DEAE-Sepharose CL-6B。根据线性回归方程计算其平均分子量,水洗多糖组分的平均分子量为1.47×105 Da,盐洗多糖组分的平均分子量分别为9.62×105、5.59×106、3.15×105 Da。结论:确定了针对发芽糙米粗多糖的去除蛋白质和脱色的方法,并筛选出最佳的柱层析填料,分离出四个组分发芽糙米多糖,为发芽糙米粗多糖的提取、纯化、分离逐渐转变为工业化生产提供了理论基础。     

κ-卡拉胶与魔芋胶复配胶的流变性能及其微观结构研究

研究κ-卡拉胶与魔芋胶(质量比为5.5:4.5)复配胶的流变特性,考察剪切速率、振动频率和温度等对复配胶流变特性的影响。研究结果表明:30℃时复配胶的储能模量G′高于κ-卡拉胶和魔芋胶单体胶的储能模量G′,其损耗模量G"低于κ-卡拉胶的损耗模量G",复配胶的凝胶性质更加明显。随着温度的升高,复配胶体系的G′始终大于G",具有典型黏弹性流体的特性。结构分析表明κ-卡拉胶与魔芋胶之间具有较好的协同作用,通过分子间氢键形成了以κ-卡拉胶网络结构为主,魔芋胶穿插其中的交联网络体系。     

Thermal,microscopic, and quality properties of low-fat frankfurters and emulsions produced by addition of different hydrocolloids

This study involves investigation of the effects of addition of different hydrocolloids on the thermal, microscopic, and quality properties of low-fat meat emulsions and frankfurters. The emulsion stability of the samples containing 0.5% κ-carrageenan, λ-carrageenan or chitosan, and the 1% chitosan containing sample were lower than that of the control group. Thermal analyses showed three denaturation peaks for minced meat at 57.42 °C, 64.21 °C and 78.58 °C. While the denaturation temperature of myosin for the sample produced with 0.5% of κ-carrageenan was significantly lower, samples containing 1% κ-carrageenan and 0.5% λ-carrageenan were not significantly different than that of the control group. The thermal denaturation temperature of myosin for samples containing 1% λ-carrageenan, and for 0.5% and 1% guar gum, xanthan gum and chitosan was significantly higher than that of the control. The denaturation temperature of sarcoplasmic proteins and actin for samples with 1% κ- and λ-carrageenan and 0.5% chitosan, was higher than for the control, while for other samples it was not significantly different. The scanning electron microscopy images of the control group and samples produced with 0.5% and 1% λ-carrageenan, 0.5% and 1% guar gum, and 1% κ-carrageenan showed gel-like structures, whereas other samples did not. Sensory evaluations showed that addition of hydrocolloids and reduced fat content lowered acceptance of frankfurters. Results showed that both κ- and λ-carrageenan, especially at 0.5% were the most suitable hydrocolloids for production of low-fat frankfurters and xanthan gum was the least suitable since it did not form proper structure.     

大目金枪鱼皮明胶与κ-卡拉胶复配胶凝胶特性探究

将大目金枪鱼皮明胶和κ-卡拉胶按不同配比混合制成复配胶,测定了复配胶的凝胶强度、流变学性质、凝胶持水性、质构、红外光谱和电镜。结果表明:复配胶的凝胶强度、粘度、储能模量和耗能模量均随着κ-卡拉胶比例的增大而增大。复配胶的凝胶持水率在明胶/κ-卡拉胶比例为7:3时为75.9%,远低于单组分明胶凝胶的97.1%,但继续增大κ-卡拉胶的比例会出现显著增大的趋势,质构特性与持水率有相同的变化趋势。红外光谱分析结果表明κ-卡拉胶与明胶之间的交互作用随着κ-卡拉胶比例的增大而减小,说明复配胶中形成了以κ-卡拉胶为主体的结构。电子扫描结果显示复配胶中出现褶皱与聚集,进一步说明κ-卡拉胶与明胶以不同比例混合后通过氢键发生了不同程度的交互作用。实际生产中,可通过改变明胶/κ-卡拉胶的配比来调节复配凝胶的特性,适应不同产品的需要。     

κ-卡拉胶脱色方法的研究

采用次氯酸钠、过氧化氢、活性碳和大孔树脂D113-Ⅲ、D201和D303对麒麟菜κ-卡拉胶进行脱色研究。比较κ-卡拉胶脱色率、多糖保留率和凝胶强度。结果表明,次氯酸钠和过氧化氢脱色后,多糖保留率和凝胶强度较低;大孔树脂D201和D113-Ⅲ多糖脱色率很低;活性炭脱色效果较好,但脱色后多糖溶液中残留的活性炭难以清除,对多糖品质有一定影响;大孔树脂D303的脱色效果较好,脱色率达到90.73%,多糖保留率85.76%,凝胶强度1103.7g/cm2。     

κ-卡拉胶与魔芋胶复配凝胶结构探讨

采用示差扫描量热仪(DSC)、红外光谱(FT-IR)及扫描电镜(SEM)对κ-卡拉胶与魔芋胶复配前后的结构进行初步探讨。结果表明：κ-卡拉胶与魔芋胶复配凝胶的－OH振动峰向低波数方向偏移;复配体系的DSC曲线吸热峰较单体胶所成峰峰形宽;SEM图像可清晰看到复配凝胶结构较单独κ-卡拉胶的致密。推测复配体系中形成了以κ-卡拉胶网络结构为主,魔芋胶分散其中的结构。     

卡拉胶/大豆11S蛋白共混体系相容性及凝胶性质研究

研究了大豆11S蛋白分别与3种不同荷电量卡拉胶组成共混体系的相容性、热性质、凝胶流变性质及微结构,并探讨了共混凝胶的成胶动力学及机理。结果表明:ι-卡拉胶对大豆11S蛋白的相容性比κ-卡拉胶弱,添加λ-卡拉胶样共混体系更易发生相分离;添加3种卡拉胶均提高了大豆11S蛋白的热变性温度,但降低了热焓值,影响效果依次是λ-卡拉胶﹥ι-卡拉胶﹥κ-卡拉胶;共混凝胶随卡拉胶所带负电荷的增加其弹性模量值呈降低趋势,且凝胶网络结构由蛋白-多糖双连续结构转变为蛋白凝胶网络单连续结构;增加卡拉胶所带负电荷可降低共混凝胶形成过程表观活化能,同时降低了温控程序终点的弹性模量值。     

Synergistic effects between κ-carrageenan and locust bean gum on physicochemical properties of edible films made thereof

The development of mixed systems, formed by locust bean gum (LBG), and κ-carrageenan (κ-car) can offer new interesting applications such as the development of edible films with particular properties. κ-car/LBG blend films with different ratios were developed, and their effects on films’ physical properties were assessed. Thermogravimetric analysis (TGA), X-ray diffraction (XRD) patterns, dynamic mechanical analysis (DMA) and Fourier-transform infrared (FTIR) spectroscopy techniques were used to highlight the interactions between the two polysaccharides. The addition of κ-car to LBG improved the barrier properties of the films leading to a decrease of water vapor permeability (WVP). Improved values of elongation-at-break (EB) were registered when the ratio of κ-car/LBG was 80/20 or 40/60 (% w/w). Moreover, the κ-car/LBG blend films enhance the tensile strength (TS) compared to κ-car and LBG films. FTIR results suggested that hydrogen bonds interactions between κ-car and LBG have a great influence in films’ properties e.g. moisture content, WVP. Therefore, different κ-car/LBG ratios can be used to tailor edible films with enhanced barrier and mechanical properties.     

Effects of soy protein hydrolysis and polysaccharides addition on foaming properties studied by cluster analysis

The objective of the work was to study foaming properties (foam overrun, drainage rate and collapse stability) of soy protein and their hydrolysates as affected by polysaccharides. As starting material a sample of commercial soy protein isolate was used (SP) and hydrolysates of 0.4, 5.0 and 5.2% degree of hydrolysis (DH) were produced by an enzymatic reaction. The polysaccharides added were xanthan, λ and κ-carrageenan, guar, locust bean gum and hydroxypropylmethylcelluloses as surface-active polysaccharides.     

Separation of Egg White Lysozyme by Anionic Polysaccharides

Anionic polysaccharides (Na-alginate, Na-carboxyl-methyl-cellulose, high methoxy pectin and κ-carrageenan) were evaluated for their suitability towards simple and more efficient separation of lysozyme from salted or fresh duck eggs and hen egg whites for use in foods. Only κ-carrageenan interacted and formed precipitates with lysozyme. Recovery of lysozyme from fivefold diluted salted duck egg whites was 60–65% and 78–81% from fresh duck and hen egg whites using 0.7%κ-carrageenan. The recovered lysozyme from the salted duck egg whites was stable during storage at 4°C for 35 days.