菊粉酶酶解菊芋提取液的试验

报道黑曲霉ＡＬ－１５４菊粉酶产生和酶解菊芋提取液的适宜条件：５％菊芋提取液,２％玉米浆、０．３％酵母膏的基本培养基,该酶活力达１４６．４ｕ／ｍｌ,是适培养条件为：ＰＨ４．５－５．０,３０℃,时间４８ｈ,酶解菊芋提取液的最适工艺条件为：ＰＨ５．０,６０℃,底物总糖浓度为１０－２０％,酶用量３．０ｕ／ｇ菊糖,酶解时间１０ｈ,底物降解率达９７．２％,酶解产物中果糖占总糖的８６．１％。     

克鲁维酵母突变株UV-G-40-3菊粉酶性质的研究

研究了克鲁维酵母突变株（Ｋｌｕｙｖｅｒｏｍｙｃｅｓ－ＵＶ－Ｇ－４０－３）所产菊粉酶的分布为胞外酶∶胞壁酶∶胞内酶比是５．７∶１．６∶１。该酶Ｓ／Ｉ为５．３,最适温度为５０℃,最适ｐＨ为４．５,在５０℃以下、ｐＨ４．５～８的范围内比较稳定,４℃贮存稳定性好,１４ｄ后仍保持７６％活力,为外切型菊粉酶,酶解粗菊糖（洋姜提取液）活性为纯菊糖的４倍。     

菊粉酶产菌株的诱变选育及产酶条件的研究

以克鲁维酵母野生为出发菌株,经紫外筛选选到一株产菊粉酶较突变株ＵＶ－Ｇ－４０－３,并对其进行了发酵条件的研究,在菊糖３％、蛋白胨３％、酵母膏１％、ＰＨ５．５、３６℃,装量３０ｍｌ／３００ｍｌ,２４０ｒ／ｍｉｎ摇瓶培养３３ｈ,酶活比野生株提高近一倍,为１３．９Ｕ／ｍｌ。     

菊粉酶产酶菌株的诱变选育及产酶条件的研究

以克鲁维酵母（Ｋｌｕｙｖｅｒｏｍｙｃｅｓ）野生株为出发菌株,经紫外线处理筛选到一株产菊粉酶较高的突变株ＵＶ－Ｇ－４０－３,并对其进行了发酵条件的研究,在菊糖３％、蛋白胨３％、酵母膏１％、ｐＨ５．５、３６℃,装量３０ｍｌ／３００ｍｌ,２４０ｒ／ｍｉｎ摇瓶培养３３ｈ,酶活比野生株提高近一倍,为１３．９Ｕ／ｍｌ。     

固定化增殖酵母酒精发酵新技术研究：第四报 薯类原料固定化增殖…

在前文基础上，利用Ｖ＝１１ｍ＾３传统发酵罐改造为并流型固定床反应器，进行木薯干原料固定化增殖酵母酒精发酵工业性试验。糖化醪糖化率Ｙｓ≥５０％，载体填充率８０Ｌ．ｇｅｌ／ｍ＾３反应器，发酵时间Ｔ１６．５ｈｒ，成熟醪乙醇浓度９．２２％，总糖利用率Ｕｗ＝９２．７％，糖醇化系数ＹＥ／ＳＰ＝０．４７１７，反应器容积乙醇产率ＰＶ＝４．５ｋｇ，Ｅｔ－ＰＨ／ｍ＾３．ｈｒ载体乙醇产率Ｐｃ＝５８．１８ｋｇＥｔ－ＯＨ／     

几丁质固定化无花果蛋白酶的研究

载体几丁质通过甲酸和戊二醛活化共价偶联无花果蛋白酶，固定化反应在给酶量为１．０ｍｇ／ｇ载体，ｐＨ７．５，４℃进行１５ｈ。制备的固定化酶表观Ｋｍ值（酪蛋白）为０．９５ｍｇ／ｍｌ，溶液酶的Ｋｍ值为０．３８ｍｇ／ｍｌ，固定化酶的最适ｐＨ范围变宽，由溶液酶的最适ｐＨ７．５－７．８变为在ｐＨ６－８范围内酶活性保持稳定；固定化酶的最适温度由溶液酶的６０℃变为３７℃。重复水解酪蛋白７次后，固定化酶保持原酶活性５     

酶法水解文蛤肉的研究

以海产文蛤肉为原料，用酶水解获得复合氨基酸水解液。水解液中含有１８种氨基酸，牛磺酸，多种维生素及微量元素，酶水解的最适条件为：水解时间４－６ｈ、温度５０－５５℃，初始ｐＨ７．０，酶添加量１．５－２．０％。酶解后，游离氨基酸含量可达５４．６２ｍｇ／ｇ鲜文蛤肉，其中必需氨基酸占５０％以上，牛磺酸为２６６ｍｇ／ｇ鲜文蛤肉，蛋白质的水解率为５６．７８％。     

Aspergillus ficuum菊粉酶的分离纯化及其酶解菊粉制备低聚果糖

采用硫酸铵分级沉淀、透析脱盐、DEAE-Cellulose离子交换色谱等分离纯化技术，从Aspergillus ficuum菌株混合酶系中分离得到4种菊粉酶组分，应用薄层层析法分离各组分水解菊粉的产物，发现其中3种组分主要含外切菊粉酶，一种主要含有内切菊粉酶。进一步对所得到的内切菊粉酶组分酶解菊粉制备低聚果糖进行了研究，研究了底物浓度、加酶量、反应温度和反应pH对低聚果糖制备的影响，确定其最适反应条件为：底物浓度50g／L、加酶量10U／g底物，反应温度45℃，反应PH6．0。在此条件下反应72h，菊粉酶解率达74％，低聚果糖得率可达50％以上，酶解产物以DP2～DP4为主。     

黑曲霉Aspergillus niger No．26菊粉酶的研究

通过筛选菌种，分离出３株菊粉酶活力较高的菌株，对其中Ｎｏ．２６菌株经过培养基组成的研究，酶活力达３７．１ｕ／ｍｌ。比原活性６．７ｕ／ｍｌ提高５．５倍。经纸上层析鉴定，在菊粉水解过程中，果糖逐步增加，未见中间产物生成，并有很强的水解蔗糖为果糖和葡萄糖，以及水解棉子糖为果糖和蜜二糖的能力。因此该酶主要为外切型菊粉水解酶。该酶在５５℃以下较稳定，最适ｐＨ为３～５，其低而宽的ｐＨ范围有防止微生物污染的能力，具备工业应用的良好性能。     

固太发酵柠檬酸渣转化为多酶蛋白饲料的研究

研究了用黑曲霉Ａ１，Ａ１５和酵母Ｙ７固态发酵柠檬酸渣生产多酶蛋白饲料。在３０℃的最适温度下，３株菌种混合进行固体发酵，粗蛋白增加量（绝干）约为１６％－１８％，酸性蛋白酶活性５１３９ｕ／ｇ，纤维素酶活性达６１ｕ／ｇ，试验结果表明；该酸性蛋白酶在１００℃加热１ｈ有８０％的酶存活，系耐高温酸性蛋白酶。     

Technical note: Application of immobilized cells of Kluyveromyces marxianus for continuous hydrolysis to fructose of fructans in Jerusalem artichoke extracts

Dead cells of Kluyveromyces marxianus having inulase (β-D-fructo fructanohydrolase E.C.3.2.1.7) activity were immobilized in alginate beads and used as a biocatalyst in a packed bed reactor and a stirred batch reactor. Fructosans of Jerusalem artichoke tubers, after extraction, were utilized for continuous or semi-continuous production of fructose. In a bed reactor packed with 100 ml of beads, a volumetric productivity of 36 g/l/hr total reducing sugars was obtained with 98% substrate conversion. When operated continuously for 30 days, a half life of 28 days was observed for the biocatalyst. Using artichoke extract containing 20% fructan solution, 98% conversion could be achieved in a batch reactor in 20 hr. Repeated cycling of beads resulted in considerable loss of catalyst from the reactor and subsequent loss in catalytic activity, thus giving a half life of only 14 days.     

菊芋渣酶解法的二次提糖工艺

利用菊粉酶酶解法提取菊芋渣中的单糖,采用单因素实验和正交实验研究提取工艺条件,优化的提取条件为:pH值4.6、酶加量25 U/g、提取温度60℃、料液比1∶25、提取时间6 h。在此条件下,单糖平均提取率为82.67%。采用薄层色谱法对酶解产物进行成分分析,结果表明,酶解液中主要含有果糖和葡萄糖两种单糖。经DNS法测定,酶解1 g底物,产物中果糖和葡萄糖的含量分别为135.9 mg和84.9 mg,两种单糖的比例为1.6∶1。     

Continuous production of very enriched fructose syrup by the conversion of glucose to ethanol from glucose-fructose mixtures in an immobilized cell reactor

The yeast Saccharomyces cerevisiae ATCC 36859, which preferentially utilizes glucose in glucose-fructose mixtures, was immobilized and used for the continuous production of very enriched fructose syrup. A syrup containing fructose as 99% of the reducing sugars was produced from a 10.1% w/v glucose and 9.8% w/v fructose mixture at a dilution rate of 0.106 h⁻¹. Later in this process when the dilution rate was increased to 0.366 h⁻¹ the ethanol productivity was 12.7 g 1⁻¹ h⁻¹. This is 16% less than the value attained in a similar medium containing only glucose as the carbohydrate. The fructose content was also increased from 55 to 95% of the reducing sugars in a food grade mixture of high fructose corn syrup and Jerusalem artichoke juice. Purification of the product with activated carbon and ion-exchange resin produced a stable, colourless and very enriched fructose syrup suitable for human consumption.     

Continuous Hydrolysis of Fructans in Jerusalem Artichoke Extracts using Immobilized Nonviable Cells of Kluyveromyces marxianus

Non-viable immobilized cells of Kluyveromyces marxianus in alginate beads having inulase (ß-2,1-fructan fructano-hydrolyase E.C.3.2.1.7) acitivity were used as biocatalyst in a packed bed reactor. Extracts of Jerusalem artichoke tubers were contacted with the biocatalyst for continuous conversion of the fructan component to fructose. In a bed reactor packed with 100 mL of beads, a volumetric productivity of 136 g/L/hr total reducing sugars was obtained with 98% substrate conversion. When operated continuously for 30 days, a 55% loss in the original activity was observed, giving a half life for the biocatalyst of 28 days.     

发酵条件对一步法发酵菊芋生产乙醇的影响

使用产菊粉酶的酿酒酵母可实现一步法发酵菊芋生产乙醇.该试验以菊芋汁为发酵培养基,研究了起始糖浓度、无机盐、温度、种子培养基、接种量和氮源对高菊粉酶活酿酒酵母Y05-步发酵菊粉生成乙醇的影响.试验结果表明:(1)菊芋汁中最适起始总糖浓度为250g/L.菊芋汁含有的较多无机盐对乙醇发酵不但没有抑制作用,反而有促进作用;(2)最适乙醇发酵温度为37℃;(3)种子培养基中使用菊粉做为碳源有利于酿酒酵母Y05产生较多菊粉酶,进而促进其乙醇发酵;(4)最适乙醇发酵接种量为15％;(5)尽管菊芋汁是一个良好乙醇发酵培养基,但补加氮源仍是必要的.补加5.0g/L玉米浆可显著酿酒酵母Y05的提高总糖利用率、最终乙醇浓度和乙醇得率.     

菊芋酸乳饮料的研制

以菊芋、牛奶为主要原料,将菊芋酶法水解,选取嗜热链球菌和保加利亚乳杆菌(1∶1)的混合菌种为发酵剂进行乳酸发酵生产酸乳饮料。通过L9(34)正交试验优化了发酵工艺参数,即蔗糖用量6%,菊芋水解液与牛奶配比为1∶5(w/w),菊芋水解液还原糖含量12%,发酵时间12h。制成的菊芋乳酸饮料滋味独特,香气浓郁,价格低廉,具有较高的营养和保健价值。     

菊芋资源的开发利用

根据国内外近期研究成果,简要介绍了菊芋的生长习性及菊芋块茎的主要成分,比较系统地介绍了菊芋资源的开发现状,其中包括菊芋粉、菊芋汁、菊糖、果糖和低聚果糖等主要菊芋制品的生产、功能性及其在食品工业中的应用。     

菊粉酶的研究进展

菊粉酶是一类能水解β-2,1-D-果聚糖果糖苷键的水解酶,属于糖苷水解酶32家族。菊粉酶是菊芋生物炼制中的关键酶,它能将菊芋一步水解,获得高纯度的果糖浆,生产燃料乙醇、燃料丁醇、单细胞油脂、生物柴油、甘露醇和乳酸等其它工业产品,在食品、医药及生物能源等领域有着巨大的应用价值。该文介绍了菊粉的分子结构及来源,概述了菊粉酶的分类、来源、克隆表达、三维结构及应用,并对菊粉酶的未来发展方向进行了展望,旨在提高人们对菊粉酶的认识,推动菊芋生物炼制的研究。     

Feeding Jerusalem artichoke (Helianthus tuberosus) to pigs

Weaned pigs were fed diets with added Jerusalem artichoke for 28 days. In a first trial, the pigs received raw tubers in addition to their normal ration. In a second trial, the pigs received dried Jerusalem artichoke (10–60 g kg^-1) in the diet. Pigs eating the raw tuber had significantly increased body weight gains due to the consumption of the raw tuber, but significantly decreased feed efficiency. Adding dried Jerusalem artichoke to the diet significantly increased weight gains. Feed efficiency was improved, but not significantly. Faecal valeric acid concentration was significantly increased in animals eating Jerusalem artichoke.     

Zur Biotechnologie fructosanhaltiger Pflanzen

On the Biotechnology of Plants with Fructosan Content. Inulin, as to its chemical nature, is a polyfructosane. Fructosanes (fructanes) are hardly less abundant in nature than starch. However, there are only few plants with sufficient fructosane content for technological utilization. The most important of them are Jerusalem artichoke and chicory. At first this paper deals with inulin and the homologous series of fructosanes. The importance of Jerusalem artichoke and chicory as agricultural crops and their respective peculiarities are pointed out as far as they are relevant for their use as technical source materials. Inulin containing plants are of interest with respect to the production of fructose and fructose syrup and as energy plants (production of ethanol). Chicory is particularly suitable as source material for fructose-(syrup-)production, Jerusalem artichoke mainly for the production of ethanol, although principally both product groups can be obtained from chicory roots and from topinambur bulbs. If inulin containing raw materials are used for ethanol production, it's of interest that yeast invertase splits polyfructosanes of higher molecular mass considerably more slowly than inulinase and yields are less satisfactory with S. cerevisiae and increasing inulin content in the mash. If yeast types are used containing inulinase and invertase, e. g. Kl. fragilis and marxianus, satisfactory fermentation can be obtained even with these types of mashes.