木梨子果实中胆碱的提取工艺研究

以木梨子果实为试验原料,采用浸提法从木梨子果实中提取胆碱,研究木梨子果实提取胆碱的最佳工艺条件。正交设计优选木梨子果实中胆碱的提取条件,用5%雷氏盐为对照品,测定波长在526nm处的吸光度。最佳提取条件是:硝酸水溶液比例为1∶5,提取时间5h,料液比为1∶20时胆碱提取量最高,为143mg/100g。     

桃金娘果单宁提取工艺优化及抗氧化活性研究

以单宁提取率为评价指标,在单因素实验的基础上,采用响应面法优化桃金娘果单宁的提取工艺,并采用磷钼络合物法评价桃金娘果单宁粗提液的抗氧化活性.结果表明,桃金娘果单宁的最佳提取工艺条件为:料液比1:58(g:mL)、乙醇体积分数60％、水浴时间90 min、水浴温度72℃,在此条件下,桃金娘果单宁提取率为2.24 g·(1...     

超声波辅助提取五倍子中单宁

以乙醇为提取剂,采用超声波辅助法提取五倍子中单宁.在单因素的基础上,通过正交试验优化了提取工艺.结果表明,最佳提取工艺条件为:盐酸体积分数2.0%,乙醇体积分数50%,超声时间120s,超声温度40℃,液料比25:1.在此条件下单宁提取率为10.52%.     

香蕉皮单宁的提取工艺研究

以香蕉皮为材料,丙酮溶液为溶剂,考察丙酮浓度、浸提温度、浸提时间和料液比对香蕉皮单宁提取效果的影响,利用正交实验对单宁的提取工艺进行优化。结果表明,影响单宁提取效果的主次因素顺序为:料液比﹥丙酮浓度﹥提取时间﹥提取温度,最佳工艺条件为:丙酮浓度为50%,料液比为1∶12 g/m L,提取温度为50℃,提取时间为2 h。     

超声波辅助提取紫茎泽兰中单宁的工艺优化

在单因素实验的基础上,应用Box-Behnken中心组合实验和响应面法实验优化超声波辅助提取紫茎泽兰中单宁的工艺条件。确定最优工艺条件为:甲醇浓度75%、提取时间45 min、液料比90:1(mL:g),在此条件下,紫茎泽兰中单宁含量为1.58%,与模型预测值1.57%相近,RSD为0.06%。     

蜀葵子脂肪油提取工艺的研究

考察了蜀葵子中脂肪油的提取工艺。通过测定油脂的理化性质优化提取方法,并通过单因素试验和正交试验设计考察提取时间、温度、功率、溶剂、料液比等因素对蜀葵子脂肪油提取率的影响。选择石油醚为最佳提取溶剂,超声为最优提取方法,提取条件为超声功率200 W,超声温度30℃,提取时间40 min,料液比1:10(g/mL),粉碎度为50目,提取次数为1次。在此条件下蜀葵子脂肪油的提取率可达12.57%。优化得到的工艺合理可行,比较适合蜀葵子脂肪油的提取。     

从石榴皮中提取单宁的最佳工艺条件研究

用有机溶剂从石榴皮中提取单宁，并用正交试验法对其最佳工艺条件进行了研究，产品色泽浅、含量高。     

微波和复合酶法提取野柿子树叶单宁的比较研究

分别使用微波和复合酶法提取柿子树叶中的单宁,并采用正交实验对提取工艺进行优化。结果表明,当微波功率为400 W,微波加热温度为50℃,微波辐射时间10 min和溶剂浓度40%时,单宁的提取率为90.12%;而在相似的提取条件下,复合酶法的单宁提取率仅为41.22%。采用微波辐射提取的方法更为有效。     

余甘子粗多酚的提取工艺优化研究

以新鲜余甘子为实验材料,粗多酚得率为评价指标,对余甘子粗多酚采用不同提取工艺提取。单因素试验探究不同因素对余甘子粗多酚提取率的影响,选最佳水平因素进行正交试验优化得到提取粗多酚的最佳工艺。正交实验得到最优组合为:乙醇浓度60%、浸提时间3 h、浸提料液比1:15、浸提温度65℃,在优化组合条件下浸提,余甘子粗多酚得率平均值可达205.54 mg/g。该工艺相对简单、可行性高、重复性好,且粗多酚提取率可达到较高的水平。     

棉花中单宁的提取及含量的测定

本实验采用紫外分光光度法测定了不同产地、不同品级的棉花中单宁的含量,确定了提取及测定棉花中单宁的各项最佳条件。实验结果表明,单宁提取的最佳条件为:液料比为30∶1、温度为85℃、提取时间为60 min;显色的最佳条件为:F-D试剂的用量为0.6 mL、饱和Na2CO3溶液的用量为1.4 mL、显色时间为25 min。     

土茯苓中鞣质提取工艺的优化

为了提高土茯苓的应用价值,对土茯苓中鞣质的提取工艺进行了探究.以丙酮溶液作为提取剂回流提取,采用络合滴定法测定鞣质的提取量,通过单因素实验和正交实验对土茯苓中鞣质的提取工艺进行优化,并采用精密度实验、重复性实验以及加标回收率实验对方法进行了评价.结果表明,最佳提取工艺为：提取温度70℃、丙酮浓度40％、料液比1：15（g：mL）、提取时间90 min.在此条件下,土茯苓中鞣质的提取量为20.77 mg·g-1.该提取工艺经济可行,方法的精密度高、重现性好.     

超声波辅助法提取朱砂七鞣质的工艺

通过单因素实验及正交实验对超声波辅助法提取朱砂七鞣质的工艺条件进行优化.确定最佳提取条件为:乙醇体积分数60%、料液比1∶15(g∶mL)、提取温度70℃、提取时间50 min,在此条件下提取2次,提取率为2.00%.超声波辅助法提取朱砂七鞣质工艺简单、省时、节能、提取率高.     

超声波提取五倍子单宁酸的研究

进行了超声波强化提取五倍子单宁酸的工艺研究,并通过对正交实验结果的回归分析,优化了单宁酸提取工艺。结果表明适宜超声提取工艺条件为:液料质量比37.1∶1,提取时间57 min,超声功率842 W,提取温度27.4℃。在优化超声提取工艺条件下,单宁酸的提取率达到93.5%,比常规提取率提高了28.4%。     

单宁的提取纯化技术研究进展

对单宁提取纯化技术的最新研究成果进行了综述,着重介绍了超声波提取、微波提取、超临界流体萃取和树脂纯化等技术在提取纯化单宁中的应用,对各种方法的优缺点进行了分析,对单宁的研究现状做出总结并给予展望,旨在为单宁的开发利用提供依据。     

Development of wood-products adhesives from mangrove bark

Mangrove bark was extracted using either water, ethanol, acetone, or various binary mixtures of these, as solvent. With plywood panels as substrates, joints prepared with adhesives derived from these extracts were tested for strength properties. In terms of the quantity of extracts from mangrove bark, water was the most effective solvent, followed sequentially by ethanol and acetone. However, in terms of the tannin content of these extracts, the order of extraction effectiveness of these solvents was reversed. The use of solvent mixtures in tannin extraction did not produce an observable synergistic effect. The quantity of extract and its tannin content were dictated primarily by the predominant solvent in the binary mixture. The reactivity of mangrove bark extracts is influenced significantly by formaldehyde concentration, cure temperature, type, and pH of the adhesive medium. Adhesive joints of significant bond strength were obtained from mangrove tannin adhesives. Prolonged cure periods, particularly at elevated temperatures, have deleterious effects on the strength properties of these adhesive joints.     

Effects of Acacia condensed tannins on urinary parameters,body mass,and diet choice of an Acacia specialist rodent,Thallomys nigricauda

The aim of this study was to investigate the dietary and physiological effects of condensed tannin ingestion on foregut fermenters, using Thallomys nigricauda, a folivorous rodent, as a model. We initially investigated the variability in physiological parameters, such as daily body mass (DM_b), daily feed intake, daily fecal energy loss (FE), daily energy intake (DEI), daily urine pH, and daily urinary ammonia and urea concentrations, in response to different diets with low condensed tannin levels. This experiment was conducted to identify which physiological variables showed the least variation in the absence of tannin. In a second experiment, we investigated the response of the same dietary and physiological parameters to the effects of high dietary condensed tannin ingestion in T. nigricauda. We hypothesized that DM_b, daily feed intake, FE, and DEI of T. nigricauda would be adversely affected by high dietary tannin content. We predicted that detoxification activity by T. nigricauda would increase at higher tannin levels. Ingestion of tannins affected the nutritional status of T. nigricauda, as shown by a decrease in body mass at high tannin levels. We also found that fewer ammonium ions were excreted in the urine by T. nigricauda, as would be expected if this were a means of regulating metabolic acidosis. The urine produced was more alkaline. This result indicates that T. nigricauda is not metabolizing these allelochemicals. Urea production was initially reduced, indicating conservation of bicarbonate ions that will neutralize blood acidity if there is detoxification. A diet choice experiment showed that tree rats avoid high tannin diets, even to the extent that they lose body mass on an alternative diet. This last-mentioned result is noteworthy because previous studies of the effects of tannins on herbivorous mammals have shown that there is physiological control rather than behavioral avoidance of the negative effects of tannin ingestion.     

高纯度食品级鞣酸的制备

采用溶剂萃取法，以五倍子为原料，水为溶媒进行浸提，再用乙酸乙酯为溶剂进行萃取，通过脱色制备高纯度食品鞣酸。结果表明，高纯度食品鞣酸的收率达60％，单宁酸含量达97．5％以上。     

五倍子中有效成分提取方法研究进展

五倍子中草药在我国分布广泛,其中有效成分使用领域也较广,因此对于其有效成分的提取成为目前研究的热点。文章介绍了五倍子中药材中存在的各种化学成分,包括鞣质、没食子酸、焦性没食子酸等,并重点阐述了目前鞣质和没食子酸活性成分的提取方法,进一步比较了各种提取技术优缺点,并对今后中草药有效成分的提取方法进行了展望。     

Detoxification of Sal Seed (Shorea robusta) Meal

The removal of tannin from sal meal with a minimum loss of other meal components e.g. protein and starch, was tried with a number of solvent systems. The effects of different variables e. g. temperature, time of extraction and pretreatment involving steaming and cooking at different pressures and for different time intervals were investigated. It was found that cooking at 10 psig. for 30 minutes followed by extraction with 90% ethanol effectively removed tannin from sal meal by about 87%. The solid matter loss to the extent of 10% was due to starch.     

Peeling of sorghum by a dry method: continuous and discontinuous methods

A study was carried out wherein two dry dehulling sorghum grain methods, the continuous and discontinuous types, were quantitatively compared in a laboratory abrasive dehulling device. Reflectance values, expressed as dehulling percentage, the percentage of kernels removed, and of kernel cracking were evaluated. Graphs of the dehulled and removed percentages as function of the contrast time for each method, revealed that the continuous process was the most efficient of both procedures. Analysis of the broken kernels indicated a similar behavior for both methods. The macrocomponent and tannin variations as dehulling advanced, as well as the reflectance values were determined with the continuous method. Findings showed that the greater proportion of tannin, fiber and ashes has been removed at the 85% extraction rate. Thus, abrasion of grains above the 65% extraction rate is not convenient, since an excessive loss of nutrients is produced without any important decrease in polyphenolic pigments and of those imparting color to the sorghum grain milling products.