大豆异黄酮糖苷及其苷元调节免疫功能的比较研究

目的:比较大豆异黄酮糖苷及游离型大豆苷元对小鼠免疫功能能力的影响。方法:将实验室提取大豆异黄酮糖苷和苷元(纯度为41%左右)的产品按照40～100mg/kg,连续灌胃21d后,与对照组相比能显著提高小鼠腹腔巨噬细胞的吞噬能力及小鼠脾重。结果:大豆异黄酮糖苷和苷元具有较强的调节小鼠腹腔巨噬细胞的吞噬能力,能刺激小鼠脾脏和胸腺器官的发育;同一剂量的大豆异黄酮糖苷和苷元雌鼠的效果要好于雄鼠,游离型大豆苷元的吸收效果明显好于糖苷。     

丹贝异黄酮生物活性增强的机理研究

以少孢根霉RT-3孢子接种在含高浓度的大豆异黄酮提取物制成的发酵基质中，发酵36h后大豆异黄酮被部分水解成相应的苷元．用从丹贝中分离的β-葡萄糖苷酶与标准品染料木素糖苷和大豆苷元的糖苷作用10min，染料木素糖苷和大豆苷元的糖苷被水解成相应的苷元．结果表明：丹贝异黄酮生物活性增强是发酵剂RT-3孢子分泌的β-葡萄糖苷酶将异黄酮由糖苷水解成苷元，而苷元比糖苷有更强的活性．     

豆制品中大豆异黄酮转化与富集的研究进展

大豆异黄酮属于黄酮类化合物,主要分为结合型大豆异黄酮糖苷和游离型大豆异黄酮苷元。游离型大豆异黄酮苷元具有比结合型大豆异黄酮糖苷更高的生理活性,如预防骨质疏松和女性更年期综合症,抗氧化和抗癌抑癌等。大豆异黄酮在食品保健方面应用前景广阔,国内外研究者对大豆异黄酮研究越发深入。该文主要综述豆制品中大豆异黄酮的转化和富集方法,旨在为生产富含大豆异黄酮苷元的功能性豆制品研究提供参考。     

纤维素酶水解大豆异黄酮糖苷混合物的抗氧化活性

大豆异黄酮主要以糖苷类型的分子形式存在于大豆中,但是其具有生物活性的部分主要是苷元.为了建立一种体外生物转化大豆异黄酮糖苷为大豆异黄酮苷元的新方法,采用纤维素酶水解70%乙醇提取脱脂大豆粕得到的异黄酮粗提物,对比了水解前后两样品的异黄酮组成差异,并测定了其清除DPPH自由基的能力.结果表明:纤维素酶能完全水解大豆苷和染料木苷为大豆素和染料木素;而不能水解丙二酰基染料木苷和丙二酰基大豆苷.纤维素酶处理以后的大豆异黄酮糖苷混合物达到DPPH自由基50%清除率所需要的异黄酮浓度是未处理的大豆异黄酮糖苷混合物的1/2.56.     

青方腐乳发酵过程中大豆异黄酮的转化研究

本文比较了青方、红方、白方和低盐红腐乳中大豆异黄酮组成和含量差异,并对青方腐乳发酵过程中大豆异黄酮含量和构型变化规律进行研究。结果表明,四种类型腐乳中大豆异黄酮基本以苷元形式存在,青方腐乳大豆异黄酮含量明显低于其他类型腐乳,仅为红方腐乳的33.01%,从单一异黄酮来看,大豆苷元和染料木素在四种类型腐乳中的含量明显高于黄豆黄素;青方腐乳发酵过程中大豆异黄酮转化研究发现,白坯中大豆异黄酮以糖苷型为主,染料木苷含量高于大豆苷和黄豆黄苷,前酵过程中糖苷型大豆异黄酮转化为苷元型大豆异黄酮,盐腌过程中糖苷型大豆异黄酮含量有轻微降低,发酵过程中苷元型大豆异黄酮总量在后酵前30 d显著下降,其中大豆苷元可能部分转化为雌马酚,导致青方腐乳大豆异黄酮含量明显低于其他类型腐乳,对其转化物质需进一步鉴定。     

纤维素酶对黑大豆和葛根异黄酮糖苷不同组分的水解活性

异黄酮主要以糖苷的分子形式存在于黑大豆和葛根中,但是其具有生物活性的部分主要是苷元.为了建立一种体外生物转化异黄酮糖苷为异黄酮苷元的新方法,采用70%乙醇提取黑大豆和葛根异黄酮,用高效液相色谱分析了纤维素酶水解前后两粗提物的异黄酮组成.结果表明:纤维素酶对于不同种类的异黄酮糖苷具有不同的水解专一性、基团专一性和键专一性,能完全水解大豆苷和染料木苷为大豆素和染料木素,而不能水解丙二酰基染料木苷、丙二酰基大豆苷和葛根素.     

大豆胚轴中异黄酮的提取及其抗血小板聚集作用的研究

从大豆胚轴提取总糖苷后，采用C18反相柱层析法分离大豆异黄酮糖苷，再将其水解制备成异黄酮苷元，并研究大豆异黄酮对人血小板聚集性的影响。结果：在体外人血小板聚集实验中，大豆异黄酮苷元均抑制ADP、胶原蛋白和肾上腺素诱导的血小板聚集。提示：大豆异黄酮可能有助于防止血栓形成。     

C18柱层析法提取大豆胚轴中异黄酮苷元

从大豆胚轴提取总糖苷后，采用C18反相柱层析法分离大豆异黄酮糖苷，再将其水解制各成异黄酮苷元。产品经薄层色谱法(TLC)和高效液相色谱法(HPLC)分析异黄酮苷元纯度和含量。     

大豆异黄酮苷元抗血浆脂蛋白脂质过氧化作用

对大豆异黄酮苷元的抗脂蛋白脂质过氧化作用进行了研究.从大豆胚轴提取总糖苷后.采用C18反相柱层析法分离大豆异黄酮糖苷,再将其水解制备成异黄酮苷元.12名健康受试者空腹食用大豆异黄酮苷元前后抽取静脉血制备血浆脂蛋白,观察血浆脂蛋白过氧化程度及氧化易感性的变化.结果表明,大豆异黄酮苷元食用后受试者血浆VLDL、LDL和HDL过氧化脂质水平明显降低;在体外进行氧化修饰时,LDL氧化延滞时间明显延长,LDL氧化易感性下降.大豆异黄酮苷元可增强血浆抗氧化能力,尤其增强LDL抗氧化修饰能力,因此能够起到防治心血管疾病的积极作用.     

大豆异黄酮苷元的提取及其抗血浆脂蛋白氧化作用

从大豆胚轴提取总糖苷后,采用C18反相柱层析法分离大豆异黄酮糖苷,再将其水解制备成异黄酮苷元,并对大豆异黄酮苷元的抗脂蛋白氧化作用进行了实验研究.12名健康受试者空腹食用大豆异黄酮苷元前后抽取静脉血制备血浆脂蛋白,观察血浆脂蛋白过氧化程度及氧化易感性的变化.结果表明,大豆异黄酮苷元食用后受试者血浆VLDL、LDL和HDL过氧化脂质水平明显降低;在体外进行氧化修饰时,LDL氧化延滞时间明显延长,LDL氧化易感性下降.大豆异黄酮苷元可增强血浆抗氧化能力,尤其增强LDL抗氧化修饰能力,因此能够起到防治心血管疾病的积极作用.     

大孔树脂分离纯化大豆胚芽中异黄酮的研究

通过柱层析的方法使大豆胚芽中异黄酮的苷元和糖苷得到有效的分离。紫外检测结果显示,大豆胚芽提取液中异黄酮含量为5.35%;HPLC检测结果显示:以AB-8大孔树脂为固定相,乙醇水溶液进行递度洗脱,可使大豆异黄酮的苷元和糖苷得到很好的分离,苷元和糖苷的纯度可达90%以上。     

Extraction yield of isoflavones from soybean cake as affected by solvent and supercritical carbon dioxide

Soybean cake has been shown to be a rich source of isoflavone and can be produced during processing of soybean oil as byproduct. The objectives of this study were to compare the extraction yield of isoflavone from soybean cake by solvent and supercritical carbon dioxide, and study the conversion of isoflavone glucosides to the biologically active aglycone by employing β-glucosidase. Results showed that with supercritical carbon dioxide extraction, a maximum yield of malonylglucoside and glucoside was generated at 60 °C and 350 bar, while a high level of acetylglucoside and aglycone was produced at 80 °C and 350 bar. Supercritical carbon dioxide extraction resulted in a lower yield of total isoflavone than solvent extraction, but the former was more applicable to extraction of acetylglucoside and aglycone, and the latter to malonylglucoside and glucoside. A peak level of aglycone was attained from conversion of isoflavone glucoside by β-glucosidase at 55 °C, pH 5, concentration 50 U/ml and incubation time of 2 h.     

Ripening temperature affects the content and distribution of isoflavones in sufu,a fermented soybean curd

Sufu, a fermented soybean curd, was prepared by ripening the salted tofu cubes in the Aspergillus oryzae‐fermented rice–soybean koji mash at 25, 35 or 45 °C for a period of 16 days. It showed that the 16‐day ripened sufu contains less total isoflavone content (629.29–739.68 μg g^?1 dried matter) than the salted tofu before ripening (942.59 μg g^?1 dried matter). Regardless of ripening temperature, ripening causes a major reduction in the content of β‐glucoside and malonylglucoside isoflavones along with a significant increase of aglycone isoflavone content. These changes were enhanced as the ripening period extended. Among the various treatments examined, sufu ripened at 45 °C showed the greatest increase in aglycone content coupled with the greatest decrease in malonylglucosides. The distribution of malonylglucosides decreased from an initial 40.32% in the tofu cube to 9.78% after 16 days of ripening at 45 °C. Meanwhile, the distribution of aglycone increased from 13.17% to 39.88%.     

萌芽-低温打浆技术制备高苷元类异黄酮豆乳粉

在传统湿法工艺技术制备豆乳粉的基础上,以萌芽大豆为原料,对热烫后的大豆进行低温打浆处理,提高豆乳粉苷元类异黄酮含量。在单因素试验基础上,采用响应面法对萌芽-低温打浆制备高苷元型异黄酮豆乳粉工艺进行优化,确定最优萌芽-低温打浆的工艺参数为萌芽温度25?℃、萌芽时间75?h、浆液pH?6.0、打浆温度57?℃、打浆时间3.5?h,响应值苷元类异黄酮含量有最优值,为6.43?mg/g。利用高效液相色谱测定豆乳粉中异黄酮种类及含量,结果发现萌芽-低温打浆可显著提高豆乳粉中总异黄酮含量及苷元类异黄酮含量（P＜0.05）,与传统湿法工艺相比,其异黄酮总含量及苷元类异黄酮含量分别增加了1.09?倍和9.37?倍。     

几种水解法制备高纯度大豆异黄酮甙元工艺比较研究

以低纯度商品大豆异黄酮为原料,利用酸水解法、超声波辅助酸水解法及酶水解法制备高纯度大豆异黄酮甙元产品。通过实验,比较这三种水解制备方法水解率、产品回收率和产品纯度,并对制备得到产品进行成分分析,选择出较佳制备高纯度大豆异黄酮甙元方法。实验结果表明,采用β―葡萄糖苷酶水解分离纯化工艺制备大豆异黄酮甙元产品,操作简单,安全环保,其产品得率、异黄酮回收率和产品纯度分别为15.1%、77.1%和92.7%,分离纯化效果较理想。     

发酵对黑豆营养及活性成分的影响研究

本试验采用百粒重为12克的黑豆为原料，对黑豆、蒸煮黑豆及发酵黑豆的营养及活性成分进行了哆究，黑豆经发酵处理后糖苷型大豆异黄酮在β-葡萄糖苷酶的作用下，可转化为游离型大豆异黄酮，使游离型大豆异黄酮含量明显提高。蛋白质、多肽、可溶性糖、游离氨基酸的含量也有所提高。     

Content composition and antioxidant activity of isoflavones in commercial and homemade soymilk and tofu

BACKGROUND: Isoflavones, found in soymilk and tofu, are one of the phytochemicals in soy‐based products that may promote good health. Homemade tofu and various homemade soymilk samples were made using different soaking, grinding, and cooking methods. The homemade samples were compared to commercial tofu and soymilk for total isoflavone content and composition as well as their antioxidant capacity. All samples were freeze‐dried and extracted with a 58% acetonitrile solution which was subsequently used to determine the isoflavone content by reverse‐phase high‐performance liquid chromatography. The antioxidant activity of extracts was determined using a modified 2,2‐azino‐bis‐(3‐ethylbenzthiazoline‐6‐sulfonic acid) method and total antioxidant capacity was reported as ascorbic acid equivalents. RESULTS: The total isoflavone, aglycone, and antioxidant levels were significantly higher in homemade soymilk and tofu (1571 µg) than in commercial samples. Homemade soymilk made by the extended boiling method yielded the highest total isoflavone (2567 µg) and glucoside (1525 µg) content. A strong positive correlation was observed between the total isoflavone, aglycone conjugates, and genistein series concentration and antioxidant capacity of soymilk. CONCLUSION: Increased moist heating time yielded the highest concentration of total isoflavones as well as aglycone conjugates and the genistein series. Increasing the duration of boiling can increase the isoflavone content of both homemade and commercial soymilk and tofu. Copyright © 2007 Society of Chemical Industry     

酱油中营养生理活性物质的研究进展

酱油除了作为调味品具有悠久的历史为人们所认识外,还含有丰富的营养生理活性物质。生理活性物质大豆多肽、类黑精、大豆异黄酮、大豆皂苷等,在抗肿瘤、抗氧化、降低胆固醇、防治心血管疾病等方面都有重要的功能。对酱油一般功能和生理活性物质及其功能做综述,为进一步生产研制营养保健酱油提供理论依据和借鉴。