Extraction of protein from skim natural rubber latex using PEG as a surfactant via low speed centrifugation and continuous flow

Protein extractions from skim natural rubber latex using 3 %w/v polyethylene glycol (PEG6000) via both low speed centrifugation and continuous flow were investigated. In centrifugal extraction, when the speed was 1000 rpm, the extractable protein (EP) content in serum increased with processing time from 5 to 30 min and when the time was fixed at 5 min, EP content increased with centrifugal speed. In addition, further washing deproteinized chips with 2 %w/v SDS solution could remove proteins with efficiencies corresponding to the efficiencies of protein removals in latex phase, implying the role of PEG in protein reduction in both steps. In continuous flow extraction, EP content increased with increasing Reynolds number or increasing mean residence time of the flow to a maximum and then dropped. The efficiencies of the centrifugal extraction and continuous flow extraction were 55.2 and 33.7%, respectively. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39900.     

灰树花多糖Sevage法除蛋白工艺的研究

研究了灰树花多糖Sevage法除蛋白的工艺,采用单因素实验确定Sevage试剂添加量、氯仿与正丁醇体积比、脱蛋白次数以及振摇时间对灰树花多糖除蛋白效果的影响,并在单因素实验基础上采用响应面法确定了灰树花多糖Sevage法除蛋白的工艺条件:多糖溶液与Sevag试剂体积比3.073∶1,氯仿正丁醇体积比4.016∶1,振摇时间25.59min,脱蛋白率为37.95%,多糖含量为78.32%。     

灰树花胞外多糖脱蛋白工艺研究

以脱蛋白效率和多糖损失率为评价指标,分别考察Sevag法、酶法和三氯乙酸法三种脱蛋白方法对灰树花胞外多糖的脱蛋白效果的影响。结果显示,三氯乙酸法脱蛋白优于Sevag法和酶法,三氯乙酸的最佳添加量为3%,此时的脱蛋白效率为68.40%,多糖损失率为21.11%。紫外光谱扫描结果显示,经过三氯乙酸脱蛋白处理后的灰树花胞外多糖在波长200～600 nm范围没有明显吸收峰,表明粗多糖中的蛋白已基本除去。三氯乙酸法可作为灰树花胞外多糖纯化的一种有效的脱蛋白方法。     

Characterization of enzyme‐deproteinized skim rubber

Skim natural rubber latex is a protein‐rich byproduct obtained during the centrifugal concentration of natural rubber latex. Skim latex has a very low dry rubber content (4–8%), and the rubber particles are smaller in size. It has a higher proportion of nonrubber solids, which are mostly proteinaceous in nature. It is difficult to coagulate, and it takes more processing time. The proteins in skim latex can be decomposed by proteolytic enzymes. This article discusses the use of stabilized liquid papain from the papaya plant (Carica papaya) for deproteinization followed by creaming for quick and easy coagulation of skim latex. The technological properties and aging characteristics of the deproteinized skim rubber are compared with those of conventionally prepared skim rubber and block rubber. The deproteinized skim rubber showed enhanced quality parameters. Particle size analysis revealed that deproteinization and creaming of the skim latex did not markedly change the particle size. Gel permeation chromatography showed a reduction in the quantity of fatty acids after deproteinization and creaming, which was reflected in the improvement of the aging characteristics in comparison with the control sample. Vulcanizates prepared with the deproteinized skim rubber had higher resilience, lower heat buildup, lower compression set, and good tensile strength and elongation at break in comparison with conventionally prepared skim rubber, and the properties were almost comparable to those of block rubber. The improvement in the mechanical properties and aging characteristics could be attributed to the reduction of the protein content, the partial removal of unsaturated fatty acids, and the removal of metal ions that were pro‐oxidants during the deproteinization and creaming process. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

剑麻果胶多糖脱蛋白方法研究

以蛋白脱除率和多糖损失率为指标比较5种方法对剑麻果胶多糖脱蛋白效果的影响。结果表明:酶法与D152弱阳离子交换树脂结合法蛋白脱除率较高,并且多糖损失率较低,综合考虑为最佳方案。最佳条件为:先在木瓜酶用量2%、pH 5.0、反应温度50℃、反应时间4 h条件下脱蛋白一次,然后再利用D152弱阳离子交换树脂,在30℃恒温,pH 5.0条件下静态吸附4 h脱蛋白一次。经过最佳条件处理,剑麻果胶多糖的蛋白脱除率88.54%,多糖损失率9.25%。     

美味牛肝菌胞内多糖提取工艺研究

通过探讨浸提时间、浸提温度、加水倍数、pH值4个因素对美味牛肝菌菌丝体多糖提取实验的影响,得出多糖浸提最佳工艺条件:加水倍数为1∶10 (w/v),pH值为6.0,在80℃下浸提3h.采用4种方法对美味牛肝菌菌丝体多糖进行脱蛋白实验,试验结果表明酶法和三氯乙酸-正丁醇法效果较好,将这2种方法结合使用效果更加,当pH值为7.0时,40℃水浴酶解1h后,再加入0.5倍于多糖溶液体积的三氯乙酸-正丁醇混合液(v/v=1∶5),振荡30min,静置1h,蛋白质残留量仅为0.16%.     

蕨麻Sevage法脱蛋白工艺研究

实验选用Sevage法进行蕨麻粗多糖脱蛋白研究,采用正交实验研究了料液比、静置时间、摇振时间、氯仿∶正丁醇(v/v)对蕨麻粗多糖脱蛋白工艺的影响。最佳脱蛋白条件是料液比1∶1、静置时间25min、摇振时间30min、氯仿∶正丁醇(v/v)5∶1。     

不同处理方法对贺兰山紫蘑菇多糖抗氧化活性的影响

采用热水浸提法提取贺兰山紫蘑菇多糖,分别考察真空冷冻干燥法、真空干燥法（丙酮乙醚洗涤、乙醇洗涤）对其抗氧化活性的影响,确定最优干燥方法;干燥后多糖再分别经Sevag法脱蛋白、大孔树脂脱色、双氧水脱色3 种方法进一步处理,采用1,1-二苯基-2-三硝基苯肼法分析不同处理方法对其抗氧化活性的影响。结果表明,真空干燥法（乙醇洗涤）对贺兰山紫蘑菇多糖的抗氧化活性影响最小;大孔树脂脱色效果优于双氧水脱色,Sevag法对该多糖抗氧化活性影响较大,应尽量避免使用。     

细胞冻融辅助热水浸提螺旋藻多糖及脱蛋白工艺优化

以螺旋藻粉为原料,将细胞冻融技术与热水浸提技术相结合提取藻多糖。通过单因素及正交试验,对冻融后破碎细胞残余物中剩余多糖的提取及Sevag法脱除蛋白进行研究,优化其工艺条件,并与传统的热水浸提工艺对比。结果表明,在料液比1:16、浸提温度80℃、浸提时间1.5h的条件下热水浸提破碎细胞残余物,效果最佳,与细胞上清液合并后的多糖总提取率达到6.64%,高于传统的热水浸提法近14%;而采用Sevag法脱除蛋白的最佳工艺条件为烷醇比5:1、料液试剂比3:1、处理次数3次。在此条件下,蛋白脱除率及多糖损失率分别为81.4%和17.3%。粗多糖质量进一步分析得,总糖含量85.3%,多糖分子质量84700u,多分散度1.306;而传统热水浸提工艺得到的多糖分子质量为54800u,多分散度2.007,其粗多糖产品质量低于细胞冻融辅助热水浸提工艺得到的产品质量。