市售蔬菜中原花青素的提取与测定

通过2种不同的方法对市售各种蔬菜中的原花青素进行提取,并测定提取液中原花青素的含量,确定各种蔬菜中原花青素含量高低的规律,并比较了2种提取方法的提取效果.用75%的乙醇溶液作为提取剂,按照料液比为1:9.14的比值分别在室温和70 ℃的恒温水浴中提取30min后,采用紫外分光光度法测定提取液中原花青素的含量.结果:采用标准曲线法定量测定提取液中原花青素含量,原花青素在3.1μg/mL～31μg/mL浓度范围内有良好的线性关系,其回归方程为A=0.00341+0.0081C,R=0.99866,且方法的精密度良好(RSD=0.24%),平均回收率在94.6%～101.2%之间,符合分析方法要求.原花青素含量基本按照颜色越浅,含量越低,颜色越深紫,含量越高的规律变化,且适当的加热能使原花青素的提取更充分.     

比色法测定不同产地黑豆皮中总黄酮的含量

目的:建立黑豆皮中总黄酮的含量测定方法,测定八个不同产地黑豆皮中总黄酮的含量.方法:以芦丁为对照品,采用硝酸铝显色,比色法在510nm处测定不同产地的黑豆皮中总黄酮的含量,并考察了黑豆皮中总黄酮的最佳处理方法,保证测定结果的准确性.结果:芦丁在0.003～0.057mg/mL范围内吸光度与浓度呈良好的线性关系,标准曲线回归方程为:Y=12X-0.0009(R2=0.9999),平均回收率为104.6％.不同产地黑豆皮中总黄酮的含量在6.873％～17.017％之间.结论:所用方法简便、准确,结果显示:不同产地的黑豆皮中总黄酮含量差异较大,山西和安徽的四种黑豆皮中含量较高.     

黑果花楸果实中花青素含量分布及抗氧化活性

研究黑果花楸的新鲜果实、果梗榨汁前后花青素含量的分布,并比较其抗氧化活性。以矢车菊素-3-O-葡萄糖苷(C3G)为标准品,利用紫外分光光度法测定榨汁前后黑果花楸果实中花青素含量的分布;并利用清除DPPH自由基的方法测定不同部位的抗氧化活性。试验结果显示花青素的标准曲线方程为y=22.381x+0.012 6,R~2=0.999 8,样品在9.9 g/m L~26.4 g/m L范围内线性关系良好,回收率为97.96%~100.77%。去除果实中水分对其含量的影响,黑果花楸新鲜果实、果梗、榨汁后果实、果梗中花青素含量分别为23.31、0.96、5.08、0.58 mg/g。其EC50值分别为91.16、916.6、126.6、607.3μg/m L。花青素含量分布的变化及其抗氧化活性分析结果显示,黑果花楸榨汁后的果渣是一种具有很好抗氧化活性且花青素含量丰富的功能食品开发原料,为其后续开发奠定基础。     

HPLC法测定不同产地黑豆皮中矢车菊素-3-O-葡萄糖苷的含量

目的：建立黑豆皮中矢车菊素-3-O-葡萄糖苷的含量测定方法,测定5个不同产地黑豆皮中矢车菊素-3-O-葡萄糖苷的含量。方法：采用HPLC法测定黑豆皮中矢车菊素-3-O-葡萄糖苷的含量,色谱柱采用Phenomenex Luna Su C18 柱 (250mm×4.60mm,5μm);流动相A相为0.5%磷酸溶液,B相为水-乙腈(50:50),进行梯度洗脱;流速0.8mL/min;检测波长520nm;柱温30℃;进样量10μL。结果：矢车菊素-3-O-葡萄糖苷标准曲线回归方程为：Y＝2×107X－33120(r＝0.9998),在 0.1041～1.041μg范围内线性关系良好,平均回收率分别为92.4%、 92.5%和95.5%,不同产地黑豆皮中矢车菊素-3-O-葡萄糖苷含量范围为5.263～12.829mg/g。结论：所用方法简便、准确,可用于不同产地黑豆皮的质量控制。     

市售蓝莓类产品的原花青素含量测定

采用紫外分光光度法对市场上蓝莓类产品中原花青素含量进行测定,在546 nm处测定吸光度,试验表明原花青素在10μg/mL~150μg/mL之间呈现良好的线性关系,认为以蓝莓为主要成分产品非常有必要标示原花青素含量,原花青素可以作为蓝莓类产品的质量控制指标。     

3种天然产物中黄酮类化合物总含量的测定

采用紫外-可见分光光度法测定3种天然产物:黄秋葵叶、水稻叶及刺苋中总黄酮类化合物的含量。用70%乙醇超声提取3种天然产物中的黄酮类化合物,以芦丁为对照品,以NaNO2-Al(NO3)3-NaOH为显色系统,在505nm处进行分光光度测定,建立标准曲线A=0.01175C-0.02247,相关度r=0.9998。结果表明,3种天然物中黄酮类化合物总含量分别为黄秋葵叶:34.40mg/g;刺苋:20.26mg/g;水稻叶:2.34mg/g。     

UV法测定益母草总生物碱含量及其不确定度评价

采用紫外分光光度法(ultraviolet spectrophotometry,UV)测定益母草总生物碱的含量,并对测定结果进行不确定度分析。采用紫外分光光度仪在530 nm处测定总生物碱含量,分析不确定度来源,并对各分量不确定度进行量化和贡献率分析,计算合成不确定度和置信区间95%(k=2)下的扩展不确定度。结果表明:10批益母草中总生物碱含量范围为19.09 mg/g～2.47 mg/g,标准合成不确定度的范围为0.33 mg/g～0.04 mg/g,扩展不确定度范围为0.66 mg/g～0.08 mg/g;其中拟合标准曲线的不确定度贡献率最高,达到62.63%。     

可见分光光度法测定马蹄皮中总黄酮的含量

建立测定马蹄皮中总黄酮含量的光谱分析方法.以40%乙醇为溶剂,微波辅助提取马蹄皮中的总黄酮.以芦丁为标准样品,以NaNO2-Al(NO3)3-NaOH为显色剂,采用可见分光光度法在510 nm测量波长测定马蹄皮中总黄酮含量.回归方程A=0.0105 C+0.0014,相关系数R2=1,黄酮浓度在8.41 mg/L～82.88 mg/L范围内服从比耳定律.测定结果显示,马蹄皮中总黄酮的平均含量为1.59%,重现性试验RSD=1.38%(n=6),平均回收率99.6%(RSD=0.799%,n=6),精密度试验RSD=1.64%(n=6).     

紫外分光光度法测定葡萄籽提取物中的原花青素含量

本文建立了葡萄籽提取物中原花青素的测定方法－紫外分光光度法。本法最低检测限为8.23μg，原花青素浓度在10.4-52.0μg/mL范围内线性相关，r=0。9996，加入浓度为52.0-520μg的原花青素标准溶液时，回收率（n=3)为96.2%-101%，RSD为0.45%-0.67%，符合测定要求。葡萄籽提取物样品经6次分析，平均含量为95.2%，铁盐催化比色法较之略高（99.3%)。本法具有测定准确、稳定、灵敏，操作简便的特点，适用于葡萄籽精提物中原花青素总量的测定。     

杜仲粉丝中活性成分同时提取条件及其含量测定研究

通过L9(34)正交实验对杜仲粉丝中活性成分绿原酸和总黄酮含量检测的最佳同时提取条件进行了优化。结果表明:杜仲粉丝中活性成分最佳同时提取条件为以30%乙醇为溶剂,于60℃浸提2h;采用紫外分光光度法检测绿原酸的最大吸收波长为325nm,标准曲线为:A=0.0491C+0.0068,R2=0.9998;采用紫外分光光度法检测总黄酮的最大吸收波长为500nm,标准曲线为:A=0.0073C+0.0221,R2=0.9997;测得杜仲活性成分绿原酸含量0.1491%、总黄酮含量0.5927%。     

Antimicrobial Activities of Phenolic Extracts Derived from Seed Coats of Selected Soybean Varieties

Soybean hulls or seed coats consist of complex carbohydrates, proteins, lipids, and polyphenols such as anthocyanidins, proanthocyanidins, and isoflavones. The polyphenolics in the seed coats give them various colors such as black, brown, green, yellow, or even a mottled appearance. In this study, the antimicrobial effects of phenolic extracts from the seed coats of different colored soybeans (yellow, dark brown, brown, and black) were evaluated against foodborne pathogens such as Salmonella Typhimurium, Escherichia coli O157:H7, and Campylobacter jejuni in broth‐cultures as well as on chicken skin. The highest total phenolic content was observed for the phenolic extract from soybean variety (R07‐1927) with black colored seed coat (74.1 ± 2.1 mg chlorogenic acid equivalent [CAE]/g extract) and was significantly different (P <0.0001) from the extract of the conventional soybean variety (R08‐4004) with yellow colored seed coat (7.4 ± 1.2 mg CAE/g extract). The extract from black colored soybean produced reductions of 2.10 ± 0.08 to 2.20 ± 0.08‐log CFU/mL for both E. coli O157:H7 and C. jejuni after 3 d when incubated in broth‐culture having 4‐log CFU/mL of bacteria, whereas a 6 d incubation was found to reduce S. Typhimurium and E. coli O157:H7 at 2.03 ± 0.05 and 3.3 ± 0.08‐log CFU/mL, respectively. The extract also reduced S. Typhimurium and E. coli O157:H7 attached to chicken skin by 1.39 ± 0.03 and 1.24 ± 0.06‐log CFU/g, respectively, upon incubation for 6 d. Soybean seed coat extracts may have a potency as antimicrobial agents to reduce foodborne bacteria contaminating poultry products.     

Carbonaceous materials from seed hulls for bleaching of vegetable oils

Seed hulls, namely cottonseed, peanut, sunflower, soybean, faba bean and lupine were evaluated as carbonaceous materials for the bleaching of crude soybean oil. The six seed hulls were activated by carbonization, steam activation and acid activation. Two reference standards, Fullers earth and Tonsil clay, were used for comparison throughout the whole study. Bleaching of crude soybean oil under vacuum at 100 °C using the treated hulls was carried out. The effect of bleaching with the different hulls on the oil characteristics was evaluated by determining the % free fatty acid, % reduction in peroxide value, % removal of phospholipids, % bleachability and oxidative stability of the bleached oils. Results revealed that bleaching with carbonized hull yielded oils with least free fatty acid content and highest oxidative stability. Bleaching with acid activated hull carbons gave oils with least content of peroxides, phospholipids together with best color. Acid activation of the hulls resulted in highest increase in surface area, pore volume and least pore dimension.     

超声微波辅助酶法提取黑豆皮水溶性膳食纤维及理化特性分析

利用超声微波辅助酶法提取黑豆皮水溶性膳食纤维,并分析其理化特性。试验结果表明,在超声微波辅助下,以料液比1:25(g/mL),纤维素添加量20 mg/g、温度为60℃条件下提取23 min,黑豆皮水溶性膳食纤维得率可达19.12%±0.23%。黑豆皮水溶性膳食纤维理化性质研究表明,黑豆皮水溶性膳食纤维的膨胀力为585.71%,持水力为11.89 g/g,持油力为10.52 g/g,乳化稳定性的乳化能力(EC)为42.45%,乳化的稳定性(ES)为64.76%,葡萄糖吸附值为19.72 mmol/L,在30、60和120 min时,葡萄糖延迟指数分别为34.65、30.48和25.72 mmol/g。浓度为10%的黑豆皮水溶性膳食纤维溶液的粘度为0.0093 Pa·s。微观结构研究表明黑豆皮水溶性膳食纤具有表面具有大量的孔隙和褶皱,这有利于提高其吸附能力。红外光谱分析表明黑豆皮水溶性膳食纤维具有典型的多糖特征。     

二次正交旋转组合设计优化药桑花青素提取工艺

在超声波辅助条件下,采用四元二次正交旋转组合设计研究乙醇体积分数、液料比、时间、温度4个因素对药桑花青素提取效率的影响,用DPS7.05软件分析得出4个因素的回归方程。结果表明,超声波辅助提取最佳工艺条件为：乙醇体积分数范围52.46%～55.93%、提取液料比范围39.51:1～42.43:1(mL/g)、提取时间范围27.77～32.23min、提取温度范围50.18～52.4℃,在此工艺条件下花青素提取效率均能达到67%以上。     

黑豆中花色苷水解工艺和定量研究

以黑豆为材料,辅助超声波提取花色苷并进行水解研究,结合单因素和正交试验,确定花色苷水解的最佳工艺组合为超声时间20min、水解时间40min、水解温度90℃、盐酸- 甲醇溶液浓度2mol/L。对水解后的提取物进行HPLC 定量分析,以体积分数10% 甲酸- 水溶液和乙腈为流动相,检测波长520nm,定量线性范围为1～250μg/mL,相关系数大于0.9999。黑豆壳中Dp、Cy、Pn 的含量依次为(31.7340 ± 1.9538)、(895.3267 ±12.9120)、(26.8699 ± 0.8815)mg/100g;黑豆中Dp、Cy、Pn 的含量依次为(1.0338 ± 0.0160)、(76.6534 ± 0.2322)、(2.1283 ± 0.3244)mg/100g。     

接骨木花青素的纯化工艺及清除DPPH自由基活性的研究

通过乙醇浸提法从接骨木鲜果和干果中提取花青素,通过膜分离技术、正己烷萃取、大孔吸附树脂纯化,从接骨木鲜果和干果中提取得到的花青素冻干粉得率分别为0.43%和1.52%,花青素含量可以达到29.32%。接骨木花青素在质量浓度为200 μg/mL时,DPPH自由基的清除率最高为89.40%,相当于维生素C的96.28%。结果表明,接骨木花青素有一定的抗氧化能力。     

利用大豆皮制备微晶纤维素的初步研究

探讨了在实验室条件下，采用酸水解法处理豆皮制备食用微晶纤维素的工艺条件。对大豆皮的成分、酸水解条件进行了初步研究。     

Protein fractionation byproduct from canola meal for dairy cattle

Fiber-protein is a byproduct arising from a process for fractionating high-quality protein from canola meal. The objective of this study was to evaluate the fiber-protein fraction by examining the chemical profiles, rumen degradation, and intestinal digestive characteristics and determining the nutritive value of the fiber-protein fraction as dietary components for dairy cattle in comparison with commercial canola meal and soybean meal. Available energy values were estimated based on National Research Council guidelines, whereas total true protein content potentially absorbable in the small intestine (DVE) were predicted using the predicted DVE/degraded protein balance (OEB) model. The results show that fiber-protein was a highly fibrous material [neutral detergent fiber (NDF): 556; acid detergent fiber (ADF): 463; acid detergent lignin: 241 g/kg of dry matter (DM)] compared with canola meal (NDF: 254; ADF: 212; acid detergent lignin: 90 g/kg of DM) due to the presence of a higher level of seed hulls in fiber-protein. Compared with canola meal, fiber-protein contained 90 g/kg of DM less crude protein (CP), 25% of which consisted of undegradable acid detergent-insoluble CP. Most of the ruminally undegradable nutrient components present in canola meal appeared to be concentrated into fiber-protein during the manufacturing process and, as a result, fiber-protein showed a consistently lower effective degradability of DM, organic matter, CP, NDF, and ADF compared with both canola meal and soybean meal. Available energy content in fiber-protein contained two-thirds of that of canola meal. The DVE was one-third that of soybean meal and one-fifth that of canola meal [DVE value: 58 vs. 180 (soybean) and 291 g/kg of DM (canola meal)]. The OEB value of fiber protein was positive and about half of that of soybean and canola meal [OEB value: 74 vs. 162 (soybean) and 137 g/kg of DM (canola meal)]. Fiber-protein can be considered as a secondary source of protein in ruminant feed.     

黑豆酱油的开发及其品质分析

以黑豆为原料,采用原池浇淋工艺制备黑豆酱油,并对其品质进行分析。结果表明,黑豆酱油呈黑褐色、酱香浓郁、味道鲜美,其可溶性无盐固形物（16.62 g/100 mL）、全氮（1.53 g/100 mL）、氨基酸态氮（0.85 g/100 mL）含量均高于黄豆酱油,原花青素含量为24.2 mg/100 g,大豆异黄酮含量为6.82 mg/100 g,并可满足相关国标特级酱油要求。黑豆酱油中共鉴定出75种风味化合物,以醇类（740.54 μg/kg）、醛类（230.90 μg/kg）、酯类（121.01 μg/kg）为主;共检测出17种游离氨基酸（含7种必需氨基酸）,总含量为37 749.61 μg/mL（其中必需氨基酸含量为16 793.43 μg/mL）。该工艺制备黑豆酱油生产周期短、产品风味丰满,具有良好的营养保健功效及开发应用前景。