共查询到20条相似文献，搜索用时 93 毫秒
1.
柚皮果胶的盐析研究 总被引：2，自引：0，他引：2
采用盐析法从柚皮果胶提取液中盐析沉淀果胶.研究了盐析剂种类对果胶沉淀得率及盐折过程中pH值对果胶沉淀得率和果胶灰分含量的影响,并探索了适宜盐析条件和盐析机理.实验结果表明:以硫酸铝钾为柚皮果胶盐析剂,适宜盐析条件为:pH值5.8.盐析温度25℃,盐析时间30 min,果胶沉淀得率可达91.4%,采用三氯化铁盐析果胶,则pH值宜控制在4.0,于60℃下盐析60 min,果胶沉淀得率达95.8%.两种盐析方法所得果胶灰分均低于5.0%.铝盐盐析的果胶为白色,铁盐盐析的果胶颜色呈浅黄色,加入脱铁助剂Aid-4后可以获得较好的脱色效果.铁盐和铝盐盐析果胶的机理相似,都是果胶中的羧基离子取代金属水合物中的羟基,与金属离子发生配位反应,生成沉淀实现果胶从溶液中的分离. 相似文献
2.
3.
4.
传统的工业化生产果胶的方法是采用真空浓缩--乙醇沉降,即在一定的温度和真空度条件下浓缩果胶液,而后采用乙醇沉降.此工艺能耗大,乙醇消耗量大,成本高,所得的果胶粉杂质含量较高.本专利是从柑橘果皮、香柚果皮、香橙果皮等果皮中提取果胶.其关键步骤是果胶液的陶瓷膜超滤分离浓缩,使果胶与小分子杂质分离,该方法常温无相变,既节省能源,又避免活性成分的分解破坏;既实现常温下浓缩果胶液,又可同步实现果胶的脱色、分离和纯化.果胶液的三效降膜蒸发进一步浓缩,大大降低了乙醇沉降过程中乙醇的消耗量. 相似文献
5.
6.
以‘龙园桃李’为研究对象,运用咔唑比色法,通过不同浓度的CaCl2溶液对贮藏期间李果实的处理,研究果实硬度及果胶含量的变化。得出结论:贮藏期间,随着李果实硬度的下降,共价结合果胶含量逐渐降低,水溶性果胶和离子态果胶含量升高;经CaCl2溶液处理后,各时期李果实硬度和果胶含量明显高于对照,硬度和果胶含量的变化比对照慢;1%CaCl2溶液浓度处理下,对李果实贮藏效果最好。 相似文献
7.
提取豆腐柴叶果胶的动力学研究 总被引：1，自引：0，他引：1
研究了酸解法从豆腐柴叶中提取果胶的动力学过程,建立了受溶解果胶分子降解影响的果胶提取动力学模型,并用数学方法确定了最大的得率和最佳的提取时间.模型可应用于描述在实验室条件下,60、70、80和90℃时用盐酸从豆腐柴叶中提取果胶的酸提取过程,确立了提取过程的速率常数,从60℃下的3.01×10-4 s-1变化到90℃下的8.64×10-4 s-1,应用该模型对豆腐柴叶果胶的提取得率进行了理论计算,获得了90℃下最佳提取时间(50.19min)时的最大得率(8.007%),模型计算结果与实验数据吻合较好.所提出的理论模型能充分描述在酸性条件下的果胶提取过程和预测果胶的最大得率、果胶降解量和最佳的提取时间. 相似文献
8.
9.
秋子梨果胶含量与果肉硬度的相关性研究 总被引：1，自引：0，他引：1
《经济林研究》2018,(4)
为了解秋子梨的后熟软化规律,以8个品种的秋子梨为材料,对参试品种果实软化前后的硬度、果胶组分含量及两者间的相关性进行了测定与分析。测定结果表明:果肉硬度变化最大的是‘八里香’,说明其软化程度最大,软化速度最快;果肉硬度变化最小的为‘小香水’。‘矮香’‘尖把’‘南果梨’此3个品种果实软化后的果胶总量均有所升高,而‘软儿’‘直把子’‘京白’此3个品种软化后的果胶总量均降低。各品种果实中水溶性果胶含量的变化范围为9.55～20.23 g·kg-1,品种间的差异和软化前后的含量变幅均大,软化后的‘南果梨’‘矮香’和‘尖把’其含量均较丰富;离子结合果胶含量的变化范围为5.39～6.92 g·kg-1,品种间的差异和软化前后的含量变幅均较小;共价态果胶含量的变化范围为8.01～14.26 g·kg-1。所有参试秋子梨品种软化前后其水溶性果胶和共价态果胶的含量都普遍高于其离子结合果胶含量。相关性分析结果表明:果肉硬度与水溶性果胶和离子结合果胶含量间均呈显著负相关,其相关系数分别为-0.55和-0.54,而与共价结合态果胶含量间呈极显著正相关,其相关系数为0.78,即当其水溶性果胶和离子结合果胶含量均上升而共价态果胶含量下降时,果肉硬度下降。8个秋子梨品种间和不同时期的果肉硬度和果胶含量的差异均达到了显著水平(P 0.05)。 相似文献
10.
为了更好地研究果胶预处理对木材耐久性的影响并提高果胶在木材利用中的潜在价值.以杉木为试验材料,采用果胶和其他防腐剂配合使用的预处理模式,测定样品的载药率和失重率的变化,分析果胶预处理对杉木耐久性的影响.结果显示,杉木经过果胶预处理之后,在接种白腐菌彩绒革盖菌的环境下,杉木的失重率会提高;在接种褐腐菌绵皮卧孔菌和球毛壳菌... 相似文献
11.
柚皮经盐酸溶液提取而得果胶提取液,分别以醇沉法和盐析法从提取液中沉淀果胶.研究并获得了两种沉淀方法的最佳沉淀条件,比较了不同沉淀方法的乙醇消耗量,探索了不同沉淀方法对果胶沉淀得率和品质的影响.结果表明:醇沉法所消耗的乙醇量几乎为盐析法乙醇消耗量的两倍.盐析法能大大降低乙醇使用量,省去稀酸提取液浓缩工序和减少乙醇回收量,节省能耗,降低生产成本,并能保证较高的沉淀得率和果胶品质. 相似文献
12.
研究结果表明，向日葵盘组成复杂，初步测定出１０多种天然化合物，其果胶含量以海绵状肉质部位最高，锯齿形苞片部位最低。用气相色谱法分别测定了向日葵盘及其果胶中各种糖基的相对含量，发现它们都含有木糖、阿拉伯糖、甘露糖、半乳糖和葡萄糖等，向日葵盘中葡萄糖含量最高果胶中含半乳糖最多。向日葵盘用水预洗得到的水溶性果胶，其酯化度大于５０％，属于高酯果胶，其表观分子量为１７３４００，向日葵盘经一分别用稀无机酸及多 相似文献
13.
14.
Gremmeniella abietina grew well in media with pectin as the sole carbon source. The fungus secreted at least one enzyme with polygalacturonase activity, and this was induced by addition of pectin to the culture medium. 相似文献
15.
Takanori Imai Hideyuki Goto Hiroyuki Matsumura Seiichi Yasuda 《Journal of Wood Science》1998,44(2):106-110
myo-Inositol-[2-3H] and d-glucuronic acid-[6-14C] were administered simultaneously to a growing stem of magnolia (Magnolia kobus DC) to label xylan and pectin, respectively, in the cell wall. Determination of the radioactivity of nitrobenzene oxidation products and sulfuric acid hydrolysates of the newly formed xylem indicated that xylan and pectin were labeled with 3H and 14C, respectively. The doubly labeled wood tissue was treated to kraft pulping, and the radioactivity of the pulping black liquor and treated wood tissue were determined at various stages of the pulping to compare the dissolving behavior between pectin and xylan during the pulping. The results showed that pectin was not dissolved as easily as xylan and was not redeposited on pulp fiber at the late stage of the pulping.Part of this report was presented at the 40th Lignin Symposium at Tsukuba, October 1995 相似文献
16.
To study the role of boron in pollen germination and pollen tube growth of Picea meyeri Rehd. et Wils., pollen grains were cultured in standard medium or boron-deficient medium. Effects of boron on the localization of pectins and callose in the walls of pollen tubes were observed by laser scanning confocal microscopy after staining with aniline blue or immunolabeling with antibodies JIM5 and JIM7. Changes in the structures of pectins and phenolics were investigated by fourier transform infrared (FTIR) microspectroscopy. Pollen germination in boron-deficient medium ranged from 18 to 24%, whereas pollen germination in standard medium reached 61%. Callose accumulated in the tip-regions of pollen tubes cultured in boron-deficient medium, but not in standard medium. Immunolabeling with antibody JIM5 revealed that acidic pectin preferentially accumulated in the tip regions of pollen tubes cultured in boron-deficient medium, whereas acidic pectin was weakly distributed along the entire lengths of pollen tubes cultured in standard medium. Esterified pectin, detected by immunolabeling with antibody JIM7, showed a similar distribution pattern in pollen tubes in both the boron-deficient and standard treatments. The FTIR spectra indicated slight increases in contents of phenolics and carboxylic acids and a substantial decrease in the content of saturated esters in boron-deficient pollen tubes compared with normal pollen tubes. The FTIR spectra confirmed that boron deficiency enhanced acidic pectin accumulation in pollen tubes, which may be associated with the increased content of carboxylic acid. We conclude that boron has a regulatory role in pollen germination and pollen tube growth. 相似文献
17.
毛竹伐桩快速腐烂技术试验研究 总被引：6，自引：0，他引：6
竹伐桩在自然状态下腐烂速度极度级慢，为加快其腐烂速度，增加土地有利用空间，试用尿素、碳酸氢铵、食盐、草甘磷等肥料或农药，木霉、果胶霉等生物菌类单种或组合施于竹桩内腔。结果表明：这些物质都能有效提高竹桩糜烂速度，但提高速率有差别。使用草甘磷与碳酸氢铵、食盐的混合处理是本试验中农药和化肥组合中的最佳组合，它在处理后2年可达到自然状态的6年，腐烂速度提高了3倍。单用果胶霉、木霉处理腐烂速度也可以提高3倍；毛竹桩先加入碳酸氢铵后覆土，再加入一定量的果胶霉、木霉，其处理后23个月竹桩的腐烂程度相当于自然状态下的6年程度，糜烂速度可提高3倍以上。 相似文献
18.
以香牙蕉（Musa cavendisihii,Me）的假茎纤维为原料,对它的水分、灰分、水溶物、脂肪和蜡质、果胶、木质素、半纤维素、含胶率和纤维素成分进行了分析。结果表明：纤维素是构成香蕉假茎纤维的主要成分,占总量的55．591％;胶质总含量41．948％,其中脂蜡质含量1．438,果胶含量6．975％,木质素含量8．742％,半纤维素含量17．378％。与其它植物纤维相比,虽然香蕉假茎纤维含纤维素量中等,含木质素较高,但仍然有开发价值。 相似文献
19.
20.
The effects of chemithermomechanical pulping (CTMP), high-temperature (HT)-CTMP pulping, and kraft pulping on the distribution of the pectin polymer, methyl-esterified polygalacturonan have been qualitatively evaluated using immunocytochemistry. Pectin was immunolocalized using an antibody (JIM7) specific for partly methyl-esterified polygalacturonan. A fluorescent antibody was linked to JIM7 and analyzed by epifluorescence microscopy. Pectin was found in both chemithermomechanical pulps in similar uneven patterns: Some fibers showed no labeling, whereas others showed extensive labeling in patches restricted to the fiber surfaces. Pectin labeling of bleached and unbleached kraft pulps did not show any presence of pectin. Labeling was correlated to the presence of compound middle lamella tissue left on the CTMP-treated surfaces. Pectin on pulp-fiber surfaces may affect the interfiber bonds and thereby the pulp properties. 相似文献