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1.
双极膜电渗析分离发酵液中L-乳酸   总被引:1,自引:0,他引:1  
采用三室型双极膜电渗析装置将发酵液中的L-乳酸钠转化为L-乳酸。探讨操作电压、流速、进料L-乳酸钠质量浓度等工艺参数对转化过程的影响,考察电渗析过程参数对转化率、物料损失率、电流效率和能耗等技术指标的影响。在最优操作条件下(流速40L/h,电压15V)对2L的100.25g/L乳酸钠发酵液进行分批重复电渗析处理。结果表明:整个过程的转化率为81.22%,损失率为1.5%,能耗为0.81kW·h/kg,电流效率为91.8%,得到的L-乳酸质量浓度可达144.31g/L.电渗析残液补糖后可回到发酵罐中用于发酵生产L-乳酸.  相似文献   

2.
猪苓发酵液抑菌活性物质的性质研究   总被引:1,自引:0,他引:1  
研究猪苓发酵液中抑菌活性成分的性质,以期将为猪苓的药用机理的研究提供部分理论依据。以大肠埃希菌、枯草芽胞杆菌、金黄色葡萄球菌、热带假丝酵母、酿酒酵母、小麦赤霉为靶标菌,研究发酵液的抑菌作用;用不同极性有机溶剂萃取活性物质,检测萃取液抑菌效果;并探索了不同温度和pH下对发酵液活性的影响;利用捷克八溶剂系统和紫外扫描对物质类型进行了初步确定。结果表明:猪苓发酵液对细菌有抑菌活性;活性物质对酸碱敏感且热不稳定,可被乙酸乙酯、三氯甲烷、正丁醇等有机溶剂萃取,随萃取极性增大萃取能力增强;紫外扫描其萃取浓缩液,表明在λ210nm处有一典型吸收峰,与酯肽类抗菌素的紫外图谱相似;捷克八溶剂系统纸层析结果显示抑菌物质为非水溶性Ⅱ型抗生素。猪芩发酵液中存在抗生素类物质,但稳定性差。在猪苓的以多糖为主要药用成分的应用过程中不发挥重要作用。  相似文献   

3.
应用HPLC一反相色谱法测定米根霉乳酸发酵液中的有机酸   总被引:11,自引:1,他引:10  
提出了一种利用高效液相色谱法分析米根霉乳酸发酵液中有机酸的方法,应用反相Wakosil-II 5C18RS色谱柱,以0.01mol/L磷酸(pH2\5)作为流动相,发酵液经稀硫酸预处理后直接进样分离定量,在10min内把其中的乳酸,苹果酸,富马酸等完全分离定量,各种酸回收率大于97%。经多次实验结果证明:本方法是测定乳酸发酵液中各有机酸的快速,有效的定量测定方法。  相似文献   

4.
本研究通过测定分离自川贝母、瓦布贝母、甘肃贝母和暗紫贝母新鲜鳞茎的15株内生真菌无菌发酵液对酪氨酸酶活性的抑制率,初步评价其次生代谢物的美白活性;并以维生素C作为阳性对照,对抑制能力较强内生真菌发酵产物的石油醚(30~60℃)、乙酸乙酯和正丁醇萃取物的酪氨酸酶活性抑制率进行研究。结果表明,分离自瓦布贝母的内生真菌WBS020、1WBY2和7WBY2的无菌发酵液抑制酪氨酸酶活性的能力显著高于其它菌株,且高温处理后可保持一定稳定性。试验还发现,上述三株菌的乙酸乙酯和正丁醇萃取物对酪氨酸酶的抑制能力显著高于其石油醚萃取物;WBS020的正丁醇萃取物,1WBY2和7WBY2的乙酸乙酯萃取物都表现较强的抑制活性。除此之外,在质量浓度为8 mg/m L时,阳性对照维生素C的抑制能力显著强于其他萃取物,但1WBY2和7WBY2菌株乙酸乙酯萃取物对酪氨酸酶活性的抑制率也可达90.86%±0.81%和88.92%±7.13%,极显著高于其它两种萃取物。说明瓦布贝母内生真菌次生代谢物中存在着美白活性成分,具有潜在的开发利用价值。  相似文献   

5.
三相流化床中固定化米根霉萃取发酵生产L-乳酸   总被引:1,自引:0,他引:1  
以TRPO/磺化煤油为萃取剂,在2L三相流床反应器中进行了固定化米根霉原位萃取和异位萃取发酵生产L-乳酸的实验,结果表明,发酵液中的pH值能被控制在3.5左右.产酸速率高达每小时.每1L固定化颗粒产生11gL-乳酸。提出了一个数学模型用以描述萃取发酵中L-乳酸的积累及在各相的分配情况。模型计算曲线与实验值符合良好。  相似文献   

6.
赵韵宇  孙伟  彭崇胜  李志勇 《生物磁学》2012,(26):5001-5004
目的:对来自海洋软珊瑚的链霉菌6-1(Streptomyces variabilisstrain6-1)进行次级代谢产物的分离和鉴定,寻找具有生物活性的化合物,为人类健康服务。方法:采用液体培养基对分自海洋软珊瑚Scleronephthya sp中的链霉菌6.1(Streptomyces vafiabilisstrain6-1)进行发酵培养,用乙酸乙酯对发酵液进行萃取;采用半制备高效液相色谱(semi-preparative HPLC)分离方法对乙酸乙酯萃取物进行分离纯化,得到单体化合物;运用电喷雾质谱(ESI—MS)、核磁共氢振(1HNMR)、核磁共振碳谱(13C NMR)和物理性质对所得单体化合物进行结构鉴定。结果:从海洋链霉菌6-1(strain6-1)发酵液的乙酸乙酯萃取物中分离得到3个单体化合物,分别鉴定为:7,4’-二羟基异黄酮(1)、5,7,4’-三羟基异黄酮(2)和丁烯酸内酯-I(3)。结论:丁烯酸内酯.I是从链霉菌属首次分离得到,化合物1和2均是从Streptomyces variabilis中首次分离得到;变异链霉菌6-1(Stmptomyces variabilis strain6-1)可以作为活性化合物3(丁烯酸内酯-I)的重要来源。  相似文献   

7.
对辽宁盘锦红海滩的盐生碱蓬内生真菌JP4-1进行鉴定并研究其促生活性产物成分。根据形态学特征及18S r DNA序列分析对菌种进行鉴定,运用过滤离心、超声破碎、萃取、旋蒸等技术提取活性成分,并采用水培法研究该菌株发酵液对水稻幼苗的促生长活性。结果显示,经鉴定,JP4-1菌株为小丛壳属(Glomerella sp.),菌丝分枝,有隔,产孢;以正丁醇处理的JP4-1菌株胞外发酵液的小分子萃取物可使水稻幼苗的株高和叶片干重分别提高10.84%和14.67%,叶绿素含量提高44.22%,促生长效果明显。碱蓬内生真菌JP4-1的胞外发酵产物对水稻幼苗具有明显的促生长作用,其中以正丁醇萃取得到的小分子活性产物促生效果最为显著。  相似文献   

8.
麻叶千里光抗菌化学成分的研究(Ⅲ)   总被引:6,自引:0,他引:6  
以革兰氏阳性菌金黄色葡萄球菌(Staphylococcus aureus)、枯草芽孢杆菌(Bacillus subtilis)和阴性菌大肠杆菌(Escherichia coli)为受试菌,采用体外抑菌圈法追踪抗菌活性部分。利用各种色谱技术对正丁醇萃取部分进行分离纯化,根据理化性质和谱学数据进行结构鉴定。从麻叶千里光的水提醇沉物的正丁醇萃取部分分离得到3个化合物:苄基-O-α-L-广吡喃阿拉伯糖基(1→6)-β-D-吡喃葡糖苷(1)、(6S,9S)-6-羟基-3-酮-α-紫罗兰醇-9-O-β-D-葡糖苷(2)和(6S,9R)-6-羟基-3-酮-α-紫罗兰醇-9-O-β-D-葡糖苷(3)。它们均为首次从该属植物中分离得到。  相似文献   

9.
石慧  陈媛梅 《生物磁学》2008,(5):854-857
目的:寻找加杨叶粗提液中的总黄酮的有效方法。方法:利用双水相体系萃取分离、紫外分光光度法直接测定。结果:萃取分离加杨叶总黄酮的最佳双水相体系是25%PEG400与12%(NH4)2SO4,最佳萃取条件为:pH=9,NaCl的添加量为3%,粗提液3mL,温度25℃。结论:该方法的相对标准偏差(RSD)≤0.28%(n=5),具有良好的精密度和选择性,为黄酮类化合物萃取分离的一种有效方法。  相似文献   

10.
利用少量廉价的萃取剂一正辛醇(正辛醇/萃余液体积比0.2:1)对萃余液中的丁醇进行萃取,萃余液中56%的残余丁醇可被回收,总丁醇得率提高了38%。萃余液经活性炭(3%,w/v)处理后,在100%回用拌料条件下一批次发酵能够正常进行。萃取发酵条件下,反复全回用萃余液5次,萃取发酵性能可以保持稳定。为丁醇萃取发酵耦联生产改良型生物柴油过程中萃余液的全回用提供了一种新型、低成本和绿色环保的方法。  相似文献   

11.
A rapid, specific, and sensitive radioassay for measuring bile acid CoA:glycine/taurine: N-acyltransferase (EC 2.3.1) has been developed. In this assay, 3H-labeled amino acids (glycine or taurine) are conjugated with unlabeled bile acid CoA derivatives to form 3H-labeled bile acid amidates. Following incubation, the 3H-labeled bile acid amidate is separated from the unreacted amino acid by an n-butanol extraction method. The extraction procedure was developed by evaluating the effects of buffer concentration and pH on the recovery of radiolabeled bile acid amidate standards in the presence of human hepatic cytosol. Highest recovery (greater than 90%) of bile acid amidate standards occurred under acidic conditions (pH 2) in the presence of 1% (w/v) SDS. When the radioassay and accompanying n-butanol extraction procedure were utilized to study the amidation of glycine or taurine with cholic acid in human hepatic cytosol, a single peak of radioactivity corresponding with either authentic glycocholate or taurocholate was detected in the n-butanol phase by high-performance liquid chromatography. This assay for bile acid CoA:glycine/taurine: N-acyltransferase activity was linear with incubation time and protein concentration. This assay should be useful in the biochemical studies of this enzyme, as well as in the examination of bile acid amidation in clinical liver specimens.  相似文献   

12.
ABSTRACT

A single phase extraction procedure employing 8% (v/v) n-butanol at room temperature extracted over 90% of alkaline phosphatase activity and over 60% of 5'-nucleotidase activity from bovine milk fat globule membranes (MFGM). For 5'-nucleotidase, higher n-butanol concentrations lead to loss of activity, while lower concentrations were ineffective in extracting the enzyme. When extractions were performed at 0°C, similar yields were obtained for alkaline phosphatase extraction with 8% (v/v) n-butanol, but 51- nucleotidase extraction required 10% (v/v) n-butanol for similar yields. However, 5'-nucleotidase was less susceptible to denaturation during extraction at 0°C. The Km values and substrate specificities for both alkaline phosphatase and 5'-nucleotidase were unchanged by extraction with 8% (v/v) n-butanol. The 8% (v/v) n-butanol extraction procedure provides a 3-fold purification step, and an enzyme preparation suitable for further purification.  相似文献   

13.
Salvia triloba (Greek sage) has been used for the treatment of various diseases and contains two bioactive triterpene acids of major interest: oleanolic acid (OA) and ursolic acid (UA). The determination of the solubility of OA and UA in different solvents is a prerequisite to select the optimal solvent. The main goal of this work was to develop a quick method of predicting the solubility of OA/UA in different solvents to get a first indication of which solvents could be considered suitable for extraction from any plant material containing at least one of these triterpenes. A novel and simple ultra-violet spectroscopy method was developed for this purpose.The best solubilities were determined in THF, dioxane and n-butanol as well as in blends of dioxane and n-butanol.  相似文献   

14.
The best conditions for extractions of free pyrroloquinoline quinone (PQQ) from crude biological samples were investigated with various organic solvents and Sep-Pak C18 cartridges. PQQ was measured with use of its native fluorescence in aqueous solution. PQQ was well extracted into n-butanol under acid conditions, and addition of NaCl did not improve the solvent extraction. PQQ, which had been extracted into n-butanol, could be re-extracted into an aqueous phase by addition of either n-heptane or pyridine, or combination of them. PQQ, which had been adsorbed to Sep-Pak C18 cartridges, could be eluted with a mixture of pyridine and water with very excellent recovery. The recovery of 1 micrograms PQQ, which had been added to 1 g human liver, brain and 1 ml plasma and had undergone the n-butanol and the Sep-Pak extractions, was 50, 75 and 105%, respectively. From the blank fluorescence, endogenous levels of free PQQ in human liver, brain and plasma were found not greater than 0.41, 0.08 and 0.13 micrograms/g or ml, respectively, if present.  相似文献   

15.
W Sakamoto  F Satoh  K Gotoh  S Uehara 《FEBS letters》1987,219(2):437-440
An acid proteinase of granulomatous tissues in rats with carrageenin-induced inflammation released kinin from T-kininogen. The kinin isolated by n-butanol extraction was separated by reverse-phase high-performance liquid chromatography into T-kinin and a T-kinin derivative. From determination of its amino acid composition and its immunoreactivity toward anti-bradykinin antiserum, the T-kinin derivative was identified as Met-Ile-Ser-bradykinin (Met-T-kinin).  相似文献   

16.
采用酶法优化进行水提醇沉得到蓝莓粗多糖.经双氧水脱色、酶解和三氯乙酸正丁醇结合法脱蛋白后通过DEAE Sepharose Fast Flow离子交换层析和sephacryl s- 300 HR凝胶过滤层析得到蓝莓多糖(BBP3-1).经紫外扫描显示无蛋白、核酸杂质.经高效液相色谱分析,BBP3-1的重均分子量Mw为18...  相似文献   

17.
The purification of industrial alpha-amylase by liquid-liquid extraction with Aliquat 336 reversed micellar solution as the extractant was studied. Seven kinds of Aliquat 336 reversed micellar solution, formed by using seven kinds of straight chain alkyl alcohols as cosolvent, have been utilized to extract industrial a-amylase. It was found that these seven kinds of reversed micellar solution can all achieve a high protein transfer efficiency in the forward extraction process. After a full forward and backward extraction cycle, however, only the reversed micelles with n-butanol as the cosolvent was found to be able to maintain the activity of alpha-amylase in the stripping solution. By using the reversed micelles of Aliquat 336/isooctane/1% (v/v) n-butanol to perform a full extraction cycle, it was found that 85% of the total activity of alpha-amylase in the industrial a-amylase could be recovered at the end of an extraction cycle and the specific activity of alpha-amylase could be concentrated about 1.5-fold; meanwhile, most of the neutral protease in the industrial a-amylase could be removed. The separation factor of alpha-amylase to neutral protease at the end of an extraction cycle can reach about 10. (c) 1995 John Wiley & Sons, Inc.  相似文献   

18.
Boric acid has been known to make a complex with 2-hydroxycarboxylic acids. Based on this principle, we have developed a new method for isolation of vanillylmandelic acid, p-hydroxymandelic acid, vanillyllactic acid, and p-hydroxyphenyllactic acid in urine. The technique involves two steps: extraction of lipophilic compounds from urine with n-butanol and selective isolation of 2-hydroxy acids in the n-butanol phase on a phenylboronate gel column. 2-Hydroxy acids were eluted from the column with 1.5 ml of 2% acetyl chloride in methanol with the recoveries of ca. 70%. According to analysis of urinary extract by gas chromatography--mass spectrometry, the mean excretion rates of the above four compounds in 12 healthy subjects were 3.68, 1.93, 0.091, and 1.08 mg/day, respectively.  相似文献   

19.
李群  谭韵雅  王平  魏琴  钱双  石丹 《广西植物》2014,(4):520-524
为进一步明确大叶桉的化学成分,对大叶桉叶水浸提液分别用不同极性的有机溶剂石油醚、乙酸乙酯和正丁醇进行萃取,对各萃取相进行GC-MS分析。结果表明:大叶桉叶水浸提液共含有37种化合物,其中,石油醚萃取相中含有20种,主成分为草酸丁基异己酯(37.24%);乙酸乙酯萃取相中含有16种,主成分为2,2-二亚甲基双[6-(1,1-二甲基乙基-4-甲基)]-苯酚(50.05%);正丁醇萃取相中含有5种,主成分为丙基-2-甲基丁酸酯(54.57%)。在所有成分中,酯类物质居多,也有少量的烯、酮、醇、苯和烷烃。1-甲基,4-(1-甲基乙基)-1,4环己二烯、2,2-二亚甲基[6-(1,1-二甲基乙基)-4-甲基]苯酚、1-十八烯和二十烷为石油醚和乙酸乙酯的共有成分;1、2-苯二甲酸单(2-乙基己基)酯为乙酸乙酯和正丁醇的共有成分。该研究进一步明确了大叶桉的化学成分,为其在医药、化工和化感方面的应用研究奠定了基础。  相似文献   

20.
采用溶剂提取及柱色谱等方法,首次对瑞香狼毒Stellera chamaejasme L.的正丁醇萃取部位进行系统研究,分离得到6个苯丙素类化合物,并运用UV、1H NMR、13C NMR等现代波谱技术依次鉴定为伞形花内酯7-O-β-D-吡喃木糖(1→6)-β-D-吡喃葡萄糖苷(1),芥子醇1,3’-双-O-β-D-吡喃葡萄糖苷(2),紫丁香苷(3),(+)-落叶松树脂醇4,4’-O-β-D-吡喃葡萄糖苷(4),(+)-松树脂醇4,4’-O-双-β-D-吡喃葡萄糖苷(5)和(+)-丁香树脂醇-双-O-β-D-吡喃葡萄糖苷(6)。其中,化合物4、6为首次从该药材中分离得到。  相似文献   

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