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膜法酵母提取海藻糖应用初探 总被引:4,自引:0,他引:4
采用超滤 纳滤技术对活性干酵母溶液中的海藻糖进行提取研究 ,结果表明 :MWCO为 5 0 0 0的卷式超滤膜可截留约 98%以上的蛋白质 ,起到纳滤预处理的作用 ;MWCO为 30 0的卷式纳滤膜对超滤液进行纳滤预浓缩和渗滤操作 ,发现浓缩过程通量随压力的增加而增加 ,随浓缩时间的延长而迅速下降 ,海藻糖截留率变化不大 ;渗滤过程表明渗透通量随渗滤时间的延长而略有增加 ,海藻糖截留率变化不大。经过超滤 纳滤处理 ,海藻糖提取率达 85 %以上 ,纯度 99.4 % ,优于传统乙醇提取方法 相似文献
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以猪血浆液为研究对象,比较截留分子量(MWCO)为20000D、10000D和5000D的卷式超滤膜对血浆浓缩效果的影响,研究超滤血浆过程中,超滤压力、超滤温度、血浆蛋白浓度、pH值和时间对超滤膜效果的影响。结果表明,MWCO=5000D膜更适合用于超滤浓缩血浆液,超滤压力和蛋白浓度对通量影响更加显著。综合考虑猪血浆蛋白加工实际情况,获得最佳工艺条件为:在1.5MPa压力下,将分离血浆液(pH值7.0—7.5、蛋白浓度7.5%~8.0%、温度13~15℃),连续超滤40min。 相似文献
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【研究目的】采用无机陶瓷膜分离提取翘鳞伞胞外多糖,考察不同孔径的膜对膜过程妁影响,优化膜通量影响因素,获得超滤膜分离最佳工艺条件;【方法】以微滤处理后的翘鳞伞发酵液为研究对象,测定了5种不同孔径超滤膜的膜通量以及多糖截留率,采用L9(3^4)正交实验优化了超滤工艺条件;【结果】在5种陶瓷超滤膜中,截留分子量为50kDa的超滤膜最适合于翘鳞伞胞外多糖发酵液分离浓缩,当压力在0.1~0.4MPa,温度在20~40℃时,压力和温度的提高均有利于超滤膜通量的增大,而料液质量浓度的增加对多糖截留率影响较小.【结论】选择50kDa的超滤膜在压力0.3MPa、温度40℃、料液质量浓度0.8g/L的条件下,其膜通量以及多糖截留率最佳。 相似文献
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聚醚砜超滤膜分离菜籽油/乙醇混合物的研究 总被引:1,自引:1,他引:0
用聚醚砜超滤膜分离菜籽油/乙醇混合物,研究了混合物中菜籽油质量分数(20%~60%)、操作压力(0.15~0.3 MPa)和时间(10~60 min)等参数对分离效果的影响,并探讨了该膜渗透通量的数学模型.结果表明:膜的渗透通量随着操作压力的升高而升高,随时间的延长和混合物中菜籽油质量分数的提高而降低;膜对油脂的截留率随着操作压力的升高、混合物中菜籽油质量分数的提高而降低.当操作压力为0.15 MPa、菜籽油/乙醇混合物质量分数为20%时,得到最高的油脂截留率为95.03%. 相似文献
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采用不同截留分子量(MWCO)的超滤膜分离制备黑豆抗氧化活性肽,研究超滤系统主要参数对膜通量的影响,确定超滤条件和膜清洗方法,并测定各级多肽清除羟自由基的能力。结果表明:采用改性PES 平板超滤膜、室温、黑豆多肽液浓度2%,pH6.5 和压力0.25MPa 的条件下分离黑豆抗氧化活性肽效果较好;依次用蛋白酶液、含SDS 的碱液和NaClO 溶液清洗超滤膜后,膜通量恢复率达95.68%;分子量小于2ku 的小分子黑豆多肽具有很强的清除·OH 能力,抗氧化活性最强。 相似文献
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分别采用截留分子质量为350 ku、300 ku、250 ku、200 ku和150 ku的超滤膜过滤米醋,对超滤平均通量、通量稳定性、米醋澄清度及盐析蛋白析出量进行比较分析,优选适于米醋过滤的超滤膜。结果表明,200 ku分子质量超滤膜超滤米醋过程中即能保证较高的超滤稳定性、平均超滤通量,实现长时间连续运行,又能有效降低米醋清液盐析后的蛋白析出量,对米醋货架期稳定性有较大的改善作用。 相似文献
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Bertrand P. Chay Pak Ting Yves Pouliot Lekh R. Juneja Tutomu Okubo Sylvie F. Gauthier Yoshinori Mine 《International Journal of Food Science & Technology》2010,45(8):1633-1640
An ultrafiltration‐based approach was integrated in the preparation of phosvitin (PVs) from delipidated egg yolk proteins. An attempt was made to concentrate PVs as well as to desalt by means of the diafiltration technique. Primary experiments were devoted to optimise the ultrafiltration performance as function of parameters such as the effects of pH, feed concentration and transmembrane pressure on permeate flux with the 10‐kDa molecular weight cut‐off (MWCO) polyethersulfone membrane at laboratory scale. Higher permeate flux values were observed at low concentration and at alkaline pH, whatever transmembrane pressure studied. Then, desalting of PVs was carried out at 50 °C with 10‐ and 30‐kDa MWCO membranes. The results showed that desalting of PVs was obtained with both the 10‐ and 30‐kDa MWCO membranes and with a few loss of protein in the permeate side. 相似文献
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为进一步分离提纯已用超滤处理的γ-氨基酸(GABA)发酵液,用两款纳滤膜先后处理超滤的滤波。MWCO为800的SR2膜对氨基酸和盐均无明显的截留作用,可以截留较大的分子。MWCO为200的SR3膜能将氨基酸很好地截留,对盐也有一定的截留作用。两款纳滤膜分离与离心分离和超滤一起,可以脱除GABA发酵液中的大部分杂质,使GABA的纯度达到31.63%,取得了较好的分离效果。 相似文献
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Pineapple juice samples were ultrafiltrated using a polysulfone 10,000 molecular weight cut-off (MWCO) membrane. However, to facilitate operations, the ultrafiltration experiments were preceeded by fractionation of juice samples using sequentially Microfiltration/Diafiltration and Ultrafiltration/Diafiltration with 8 μm; 0.4 μm; 0.2 μm and 0.1 μm membranes, using three specific experimental procedures. the 10,000 MWCO membrane was cleansed using a 40°C IN NaOH solution for a minimum of 30 min, to restore optimal membrane water permeation flux. the effects of selective fractionation processes, pretreatments (using antifoaming agent, hemicellulase, and ammonium sulfate saturation), on permeation rates, concentration levels, protein rejection and protein yields were determined. Water permeation fluxes, measured before and after each UF operation showed a dramatic flux drop from 313 L/hm2 to 91 L/hm2 within seven successive 10,000 MWCO membrane experiments. This occurred inspite of suitable membrane washing conditions, pretreatments and selective fractionation processing of samples. the modification, mainly due to fouling, of the integrity of the 10,000 MWCO membrane relative to concentration level was investigated. 相似文献
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C. Gavazzi-April S. Benoit A. Doyen M. Britten Y. Pouliot 《Journal of dairy science》2018,101(11):9670-9679
High-milk-protein concentrates (>80% on a dry weight basis) are typically produced by ultrafiltration (UF) with constant-volume diafiltration (DF). To maximize protein retention at a commercial scale, polymeric spiral-wound UF membranes with a molecular weight cut-off (MWCO) of 10 kDa are commonly used. Flux decline and membrane fouling during UF have been studied extensively and the selection of an optimal UF-DF sequence is expected to have a considerable effect on both the process efficiency and the volumes of by-products generated. The objective of this study was to characterize the performance of the UF-DF process by evaluating permeate flux decline, fouling resistance, energy and water consumption, and retentate composition as a function of MWCO (10 and 50 kDa) and UF-DF sequence [3.5×–2 diavolumes (DV) and 5×–0.8DV]. The UF-DF experiments were performed on pasteurized skim milk using a pilot-scale filtration system operated at 50°C under a constant transmembrane pressure of 465 kPa. The results showed that MWCO had no effect on permeate flux for the same UF-DF sequence. Irreversible resistance was also similar for both sequences, whatever the MWCO, suggesting that soluble protein deposition within the pores is similar for all conditions. Despite lower permeate fluxes and greater reversible resistance for the 5×–0.8DV sequence, the overall energy consumption of the 2 UF-DF sequences was similar. However, the 3.5×–2DV sequence required more water for DF and generated larger volumes of permeate to be processed, which will require more membrane area and lead to greater environmental impact. A comparative life cycle assessment should however be performed to confirm which sequence has the lowest environmental impact. 相似文献
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本实验以大豆秸秆酶解液为原料,发酵制备L- 乳酸。首先对产L- 乳酸的四株菌进行筛选,选出性能优良、糖利用率和乳酸产量均较高的干酪乳杆菌作为实验用菌种。然后对乳酸菌发酵大豆秸秆酶解液制备L- 乳酸的影响因素进行了研究,研究结果表明:干酪乳杆菌发酵的最佳接种量为10%,最适发酵温度为30℃,最佳pH 值为5.5;在发酵42h 时,大豆秸秆酶解液中残留糖浓度接近于零,此时,随底物浓度的增高,乳酸产量相应增加,并且酶解液浓度达到34.98g/L 时,乳酸生产没有受到抑制。 相似文献
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超滤分离麦草浆黑液主要成分的研究 总被引:10,自引:0,他引:10
利用截留相对分子质量分别为1K,5K,10K的改良纤维素膜对不同浓度的麦草浆黑液进行了超滤研究,研究结果表明:在种膜中,截留相对分子质量为10K膜的水通量最大,5K膜的水通量最小,黑液经超滤处理后,截留液中Klason木素,总木素含量增加,灰分,糖及糖醛酸含量有一定程度的降低,酸溶木素含量变化不大,透过液中酸溶木素,灰分,糖及糖醛酸含量增加,而Klason木素及总木素含量降低,同时黑液得到一定程度的浓缩,恒压越滤与普通超滤相比,其所得的截留液中Klason木素,酸溶木素及总木素均比普通超滤高,而灰分,糖及糖醛酸的含量则比普通超滤低,但黑液被稀释。 相似文献