三种预处理法对酶解产大豆异黄酮苷元的影响

以市售大豆异黄酮粉为样品,采用炒制、微波、烘箱加热法对其进行预处理,研究其对酶解大豆异黄酮转化大豆异黄酮苷元含量的影响。结果表明:炒制效果明显好于烘箱和微波法(p<0.05),炒制后大豆异黄酮苷元含量比烘箱、微波处理后分别增加1.238、1.240 mg/g。再运用单因素、响应曲面法对炒制条件进行优化,得到最优条件为:炒制时间103 s,炒制温度137℃,物料量13 g,此时大豆异黄酮苷元含量和转化率为13.33 mg/g、72.23%。      

酶解制备苷元型大豆异黄酮

以大豆异黄酮糖苷为原料,酶解制备苷元型大豆异黄酮。以水解率和苷元得率为指标对几种来源的β-葡萄糖苷酶、β-半乳糖苷酶、纤维素酶进行筛选,确定最适酶解用酶。通过单因素实验对酶添加量、底物质量浓度、酶解温度、pH、酶解时间进行优化。结果表明,最佳酶解工艺条件为：采用β-葡萄糖苷酶（300 U/g）,酶添加量7%,底物质量浓度1.6 mg/mL,酶解温度56 ℃,pH 4.8,酶解时间6 h。在最佳工艺条件下,大豆异黄酮糖苷的水解率及苷元得率分别达到96.84%和99.74%。     

酶水解对大豆异黄酮粗提物中苷元含量的影响

采用β-葡萄糖苷酶水解的方法将大豆异黄酮糖苷转化为苷元,以染料木素和大豆苷元含量为指标,通过单因素试验对水解过程中的不同影响因素进行了考察。以染料木素含量为指标,运用正交试验优化了β-葡萄糖苷酶水解大豆异黄酮的工艺条件为反应温度40℃、水解时间1.5h、水解介质pH4.5、水解底物浓度10mg/mL,在此条件下,水解得到的大豆异黄酮苷元中染料木素的含量可达到22.91%。     

大豆异黄酮苷元的纯化

以大豆异黄酮糖苷水解产物为原料,分离纯化染料木黄酮和大豆苷元.以丙酮为溶剂进行萃取分离,通过单因素实验考察溶剂体积、萃取温度和萃取时间对分离效果的影响,最终确定分离条件为:加入30倍体积丙酮,15℃分离20 min,最终产品染料木黄酮纯度72.3%,回收率89.5%;大豆苷元纯度67.7%,回收率84%.     

两步水解酶法制备大豆异黄酮苷元初探

利用二步水解法制备大豆异黄酮苷元。经弱碱水解丙二酰基大豆异黄酮为糖苷型大豆异黄酮,再经果胶酶进一步水解获得富含苷元的大豆异黄酮。采用单因素试验和正交试验,得到果胶酶制备大豆异黄酮苷元的较优工艺条件:果胶酶水解时间20 min,水解温度47.5℃,水解pH值4.2,酶-底物质量比为0.80%。苷元水解得率为87.37%。     

发酵酶解耦合法大豆苷元转化工艺

以市售大豆异黄酮粉为样品,选用产β-葡萄糖苷酶的LJ-Q2菌种与优化后的固定化β-葡萄糖苷酶进行耦合发酵,采用单因素、响应曲面法对耦合发酵条件进行优化,高效液相法（HPLC）测定大豆异黄酮苷元,考察耦合发酵条件对大豆苷元转化率的影响。研究结果如下:最优条件为温度54℃,耦合时间3 h,初始p H7,固定化酶添加量7%;大豆异黄酮苷元绝对质量13.76 mg,大豆异黄酮苷元转化率为76.8%。对大豆苷制备应用技术开发有参考价值。      

大豆异黄酮及其苷元的研究进展

大豆异黄酮是一种天然的雌激素,是大豆生长过程中的次级代谢产物,其主要位于大豆种子的子叶和胚轴中。其中97%左右以糖苷形式存在,其余以苷元形式存在,大豆异黄酮苷元是其发挥主要功能活性的形式。目前大豆异黄酮的常规提取方法包括有机溶剂萃取法、超声波辅助提取法、微波辅助提取法、超临界流体萃取法、亚临界水法等。研究表明,大豆异黄酮及其苷元具有一定的生理功效,包括预防心血管疾病,预防骨质疏松,抗肿瘤和神经保护等。本文在介绍大豆异黄酮及其苷元的组成、化学结构特性的基础上,详细综述了大豆异黄酮及其苷元的研究概况、提取工艺和主要功能活性,并展望了该领域今后的发展趋势和有待加强的研究方向,旨在为大豆异黄酮及其苷元产业化开发和深入研究其临床应用价值提供参考依据。     

固态发酵法制备大豆异黄酮苷元

研究了一种能分泌β-葡萄糖苷酶的黑曲霉作为菌种对大豆异黄酮粉进行发酵生产大豆异黄酮苷元的方法,通过单因素及正交试验确立了产β-葡萄糖苷酶的最优培养基配比和水解大豆异黄酮粉的最佳工艺条件,为实现大豆异黄酮苷元的产业化生产提供了参考.     

复凝聚法制备大豆异黄酮苷元微胶囊的研究

以明胶和壳聚糖为壁材,采用复凝聚法制备大豆异黄酮苷元微胶囊.通过单因素试验和正交试验,研究不同因素对微胶囊制备效果的影响,优化制备工艺.结果表明:在系统浓度为1.0%,复凝聚pH值6.2,芯壁比为5:1,复凝聚温度30℃条件下,微胶囊的包埋率可达79.4%.     

热处理与大豆异黄酮苷元的转化分析

目的研究不同加热处理后大豆异黄酮苷元的含量和比例变化情况。方法大豆样品经烘箱50、100和150℃烘干,微波加热5min和炒熟等热处理后,由80%乙醇溶液超声提取,经高效液相色谱SB-C18柱(4.6mm×250mm,5μm)分离,0.2%冰乙酸+甲醇溶液梯度洗脱,紫外检测器260nm检测苷元和β-葡萄糖苷型大豆异黄酮含量。结果黄豆中检测出黄豆苷元、染料木素2种苷元和黄豆苷、黄豆黄苷2种β-葡萄糖苷。随烘箱加热温度升高,黄豆苷元含量增加1～5倍;染料木素增加3～15倍。炒豆中苷元和β-葡萄糖苷增加量最多。微波加热与50℃烘箱加热结果基本相同。青豆、黑豆与黄豆结果相近。结论加热使豆粉中部分糖苷型大豆异黄酮分解转化为苷元,活性成分增多,营养保健价值提高。     

麦芽糖浆预处理对酶法生产海藻糖的影响研究

利用酵母发酵法预处理去除麦芽糖浆中葡萄糖,以消除底物抑制提高酶法生产海藻糖产率。实验以产朊假丝酵母为发酵微生物,以麦芽糖浆中的葡萄糖去除率为指标,采用单因素及正交实验方法探讨不同因素对葡萄糖去除率的影响,并确定最佳工艺参数。结果表明:麦芽糖浆体积分数40%,酵母菌液接种量4%,p H5.5,温度32℃条件下,发酵6 h后葡萄糖的去除率可达99.4%。以此糖浆为酶反应底物生产海藻糖,海藻糖产率由初始29.8%提高至58.4%,涨幅达96.0%。研究结果对工业化利用麦芽糖浆酶法生产海藻糖提供有效数据及理论支持。      

The effect of enzymatic pretreatments on subsequent octenyl succinic anhydride modifications of cornstarch

Cornstarch granules were allowed to react with α-amylase and then esterified with octenyl succinic anhydride (OSA). The paste properties and the distribution of octenyl succinate (OS) groups of OS-starch granule were studied. Results show that the α-amylase pretreatments significantly decreased the degree of substitution (DS) of OS-starch compare with a non-pretreated control group, while the retrogradation properties, freeze-thaw stability and shearing resistant stability of α-amylase pretreated OS-starch didn't change markedly. Enzymatic pretreatment appears to influence the distribution of the OS groups from being mostly on the surface and amorphous part of the starch granules to being in the inner amorphous and crystalline regions of the granules, as shown by X-ray photoelectron spectroscopy (XPS) and lintnerisation studies.     

Ecofriendly natural dyeing of woollen yarn using mordants with enzymatic pretreatments

In this study, woollen yarn was dyed with industrial rose pulp from Isparta, a process that may pose environmental risks. The woollen yarn was processed with Savinase 16L, a protease enzyme, then dyed with biomordants such as citric acid, tannic acid and acetic acid, as well as with metal mordants such as aluminium sulphate, aluminium potassium sulphate, ferrous sulphate and potassium dichromate. The results showed that the yarn pretreated with the protease enzyme exhibited increased dyeability and pilling values without excessive loss of weight or strength. Although different shades were obtained with biomordants, different colours were obtained with metal mordants. The analysis of the waste water and metal content of the final product showed compliance with the OEKO-TEX^® Standard 100.     

预处理对航空米饭粘弹性影响

为改善航空米饭食用品质,对米饭加工工艺预处理条件进行分析和优化,实验结果表明,大米经添加0.6%β–环状糊精浸米水,30℃,浸泡45分钟预处理后煮成米饭具有良好粘弹性,可减轻低温冷藏所造成老化现象。     

Effect of liquid nitrogen pretreatments on osmotic dehydration of blueberries

Fresh blueberries are highly perishable and must be preserved by either freezing or drying technologies. However, moisture impermeability of their skin is a barrier against the moisture diffusion slowing down the drying process. The aim of this study was to investigate the impact of liquid nitrogen pretreatments on osmotic dehydration kinetics of two blueberry species, Vaccinium corymbosum L. and Vaccinium angustifolium Ait, and on the physicochemical quality of dehydrated fruits.     

Effect of pretreatments and drying temperatures on sweet potato flour

Effect of pretreatments with 1 w/v% sodium hydrogen sulphite (NaHSO₃) and 1 w/v% calcium chloride (CaCl₂) and drying temperatures (55, 60 and 65 °C) on sweet potato flour were investigated. Flour treated with CaCl₂ had higher amounts of ascorbic acid and β‐carotene (10.61–12.54 and 3.26–3.46 mg 100 g^?1 wet basis, respectively) than that treated with NaHSO₃ (9.47–11.47 and 3.05–3.43 mg 100 g^?1 wet basis, respectively). Total phenolic content and water absorption index (wet basis) were highest at 65 °C when treated with NaHSO₃ (10.44 mg 100 g^?1 and 2.49 g g^?1 respectively) and CaCl₂ (9.52 mg 100 g^?1 and 2.85 g g^?1 respectively). Swelling capacity (wet basis) was highest at 60 °C when treated with CaCl₂ (2.96 g g^?1) whereas when treated with NaHSO₃ (2.85 g g^?1) it was highest at 55 °C. Freeze‐dried samples treated with NaHSO₃ had higher lightness and total phenolic content while CaCl₂‐treated samples had higher β‐carotene and ascorbic acid. The results showed that good quality flour could be produced after soaking in CaCl₂ and dried at 65 °C.     

Effect of ultrasound,centrifugation, and enzymatic pretreatments on phytochemical properties and membrane fouling during microfiltration of Sohiong (Prunus nepalensis L.) juice

Food Science and Biotechnology - The study aimed to investigate the effects of various pretreatment methods on sohiong fruit juice during the microfiltration process. The ultrasound,...     

Effect on both aglycone and sugar moiety towards Phase II metabolism of anthocyanins

The effect of sugar moiety on anthocyanin metabolism was studied using anthocyanidin 3-rutinosides (cyanidin 3-O-rutinoside (Cy3R) and delphinidin 3-O-rutinoside (Dp3R)) and 3-O-glucosides (delphinidin 3-O-glucoside (Dp3G)). O-methylated Cy3R and Dp3R were detected in rat blood plasma after oral administration of Cy3R and Dp3R (100 mg/kg body weight). On the basis of HPLC retention time and UV–visible spectra together with the data of our previous studies on the hydrophobic metabolites of anthocyanidin 3-O-glucosides, it was concluded that both 3′- and 4′-O-methyl Cy3R were metabolites of Cy3R. On the other hand, only 4′-O-methyl Dp3R was detected as hydrophobic metabolite of Dp3R. A group of hydrophilic metabolites was also detected in rat blood plasma after oral administration of anthocyanins (Dp3G, Cy3R and Dp3R) and their structures were determined to be extended glucuronides and their O-methyl analogues by tandem MS analysis. The amounts of extended glucuronides of Dp3G, Cy3R and Dp3R were less than those of cyanidin 3-O-glucoside (Cy3G) reported in our previous study. On the other hand, anthocyanidin–glucuronides (both cyanidin–glucuronide and delphinidin–glucuronide) were not detected after oral administration of Cy3R, Dp3R and Dp3G. These results indicated that both the type of sugar moiety and stability of aglycone largely affected phase II metabolism of anthocyanins, and also indicated that the type of sugar moiety did not affect the O-methylation metabolism but affected glucuronyl conjugation in both liver and small intestine.     

不同预处理方式对紫薯花色苷提取效果的影响

分别采用冷冻干燥、保鲜贮藏、冷冻贮藏和烘干处理等方式对紫薯原料进行预处理,研究其对花色苷提取得率的影响.结果显示对花色苷得率的影响程度由大至小依次是鲜紫薯冷冻干燥、鲜样品保鲜贮藏、鲜样品冷冻贮藏、鲜样品烘干.鲜样品冷冻干燥提取得率最高,为98.5mg/100g鲜紫薯,鲜样品烘干提取得率最低,为6.9mg/100g鲜紫薯,鲜样品保鲜贮藏和鲜样品冷冻贮藏的花色苷提取得率非常接近,分别为65.7mg/100g鲜紫薯和65.4mg/100g鲜紫薯.