首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 78 毫秒
1.
Volume 60, no. 7, p. 2593, abstract, line 11: "radiolabeled either" should read "radiolabeled ether." Page 2594, column 1, line 13 from bottom: "KH(inf2)PO(inf4) (350 pmg/liter)" should read "KH(inf2)PO(inf4) (350 mg/liter)." [This corrects the article on p. 2593 in vol. 60.].  相似文献   

2.
Volume 61, no. 1, abstract, lines 4 and 5: "2,6-dichloro-4-R-phenols, where . . ." should read "2,6-dichloro-4-R-phenols (2,6-DCl-4-RPs, where R is -H, -F, -Cl, -NO(inf2), -CO(inf2)(sup-), or -COOCH(inf3)) . . ." Line 6: ". . . bromophenols (2-BrP, 2,6-DBrP, and 2-Br-4ClP)" should read ". . . the bromophenols 2-BrP, 2,6-DBrP, and 2-Br-4-ClP." [This corrects the article on p. 346 in vol. 61.].  相似文献   

3.
Small doses of (NH4)2HPO4 or KH2PO4 by stomach tube caused increase in plasma PO4 and PO4 excretion. Above a threshold of 0-8 mmol. 1(-1), increase of plasma PO4 by 0-5 mmol. 1(-1) caused PO4 excretion to increase by about 35 mumol. min.-1 After KH2PO4 this relationship was not altered by the concurrent increases in plasma K and K excretion. After doses of (NH4)2SO4 or K2SO4, excretion of SO4 was similarly related to plasma SO4 and was independent of plasma K and K excretion. An effect of PO4 on K excretion was observed after doses of (NH4)2HPO4, when increased excretion of PO4 was accompanied by increased excretion of K without change in plasma K. There was also increased excretion of NH4 and a small increase in Na excretion. The changes were similar to those produced by (NH4)2SO4 [O'Connor and Summerill, 1976]. KH2PO4 and K2SO4 produced increase in plasma K and increased excretion of K not significantly different from the changes produced by KCl or KHCO3 [Baylis and O'Connor, 1976]. After KH2PO2 or K2SO4, the urinary anion was PO4 or SO4, instead of Cl and HCO3. Any effect of anions on K excretion was much less than the effect of increase in plasma K. At low rates of excretion of K, increased urinary excretion of impermeant anion can determine increased excretion of K. However, the effect of anion is small in comparison with the effect of increase in plasma K.  相似文献   

4.
研究了毕赤氏酵母植酸酶工程菌高密度生长的培养条件 ,包括不同碳源、酵母粉、(NH4 ) 2 SO4 、KH2 PO4 等不同用量对菌体生长的影响。结果是甘油 4 %、蛋白陈 2 %、酵母粉 0 5%、(NH4 ) 2 SO4 0 .8%、K2 HPO4 0 1%、KH2 PO4 0 6 %。在此基础上 ,对温度、起始pH、接种量等影响该工程菌菌体生长的因素也作了初步研究。  相似文献   

5.
Volume 61, no. 4, p. 1211, column 2, line 40: this sentence should read as follows. "The viable-culture methods for Legionella sp. detection, however, often fail, and the Centers for Disease Control and Prevention has turned, when necessary, to PCR for epidemiological investigations of Legionnaires' disease and Pontiac fever (19)." Line 46: "(6)" should read "(11)." [This corrects the article on p. 1208 in vol. 61.].  相似文献   

6.
Vol. 62, no. 10, p. 3684, column 2, line 16: "Tri(methylsilyl)" should read "Tri(trimethylsilyl)." Line 17: "Di(methylsilyl)" should read "Di(trimethylsilyl)." Line 20: "Tri(methylsilyl)" should read "Trimethylsilyl." Page 3686, column 1, reference 12: The journal should be Dokl. Akad. Nauk Belarusi. [This corrects the article on p. 3679 in vol. 62.].  相似文献   

7.
利用响应面法优化L-组氨酸摇瓶发酵培养基   总被引:2,自引:1,他引:1  
通过单因素实验对L-组氨酸产生菌LGS4的发酵培养基成分进行筛选,确定了3个影响较大的重要因素,即酵母膏、尿素、硫酸镁。在此基础上,采用二次响应面分析法进行回归分析,得到各因素的最佳水平值。经5批培养验证,预测值与验证试验平均值接近。优化后培养基组成为(g.L-1):蔗糖150,硫酸铵50,酵母膏10,尿素1.2,MgSO42.2,KH2PO41.5,K2HPO40.5,Na2HPO40.5。优化后的发酵培养基使LGS4菌株的L-组氨酸产量提高了15.25%。  相似文献   

8.
Vol. 61, no. 2, p. 635, legend to Fig. 3, line 1: "VS ( )" should read "VS ((symbl))." Legend to Fig. 4, line 3: "DS81-D ( )" should read "DS81-D ((symbl))." [This corrects the article on p. 630 in vol. 61.].  相似文献   

9.
The superoxide-dismutase (EC 1.15.1.1) activity was revealed in blood plasma after its successive treatment with alcohol, chloroform and one- or two-substituted phosphate. Its value is the highest when treating plasma with KH2PO4. The boiling of the supernatant liquid obtained after addition of K2HPO4 leads to a complete loss of the activity. The treatment of plasma with KH2PO4 provides higher stability of the enzyme to thermal actions. The analysis of EPR-spectra has shown the presence of different complex compounds of copper ions in the supernatant liquid. Certain experiments with the use of aqueous solutions of CuCl2 and histidine have shown that Cu2+ inhibits the superoxide-dismutase activity in samples treated with KH2PO4 and increases it in samples treated with K2HPO4.  相似文献   

10.
Nutrition had highly influence on the antibiotic production by Xenorhabdus nematophila YL001. Glucose and peptone were identified as the best carbon and nitrogen sources that significantly affected antibiotic production using one-factor-at-a-time approach. Response surface methodology was applied to optimize the medium constituents (Glucose, peptone and minerals) for antibiotic production by X. nematophila YL001. Higher antibiotic activity (328.9 U/ml) was obtained after optimizing medium components. The optimal levels of medium components were (g/l): glucose 6.13, peptone 21.29, MgSO(4).7H(2)O 1.50, (NH(4))(2)SO(4) 2.46, KH(2)PO(4) 0.86, K(2)HPO(4) 1.11 and Na(2)SO(4) 1.72. An overall 16% and 35% increase in antibiotic activity were obtained as compared with mean observed response (283.7U/ml) at zero level of all variables and YSG medium.  相似文献   

11.
【目的】提高重组谷氨酸棒杆菌发酵L-苯丙氨酸(L-phenylalanine,L-Phe)的产量。【方法】使用正交试验设计以及响应面优化法分别对种子培养基及发酵培养基进行优化,确定了重组谷氨酸棒杆菌发酵L-Phe的最佳种子培养基及最佳发酵培养基。【结果】重组谷氨酸棒杆菌发酵L-Phe最佳种子培养基(g/L):葡萄糖25.0,玉米浆25.0,硫酸铵15.0,硫酸镁1.0,磷酸二氢钾2.0,尿素2.0,p H 6.8-7.0;最佳发酵培养基(g/L):葡萄糖110.0,玉米浆7.0,硫酸铵25.0,硫酸镁1.0,磷酸二氢钾1.0,柠檬酸钠2.0,谷氨酸1.0,碳酸钙25.0,p H 6.8-7.0;在最佳培养基条件下L-Phe产量最高达到9.14 g/L,较优化前的7.46 g/L提高了22.5%。【结论】通过正交试验和响应面分析对重组谷氨酸棒杆菌发酵L-Phe培养基进行优化,明显提高了L-Phe的产量,并确定了葡萄糖、玉米浆和硫酸铵为发酵培养基中影响L-Phe产量的3个关键因子。研究结果为L-Phe的发酵放大提供了依据。  相似文献   

12.
采用正交设计法对耐底物腈水合酶融合子的发酵条件进行优化,以发酵液起始pH,发酵周期,接种量,装料系数作为考察因素,最终确定最佳发酵条件为:起始pH8.0、发酵周期54h、接种量12%、装液系数12%.在此优化条件下融合子腈水合酶的活力达到1100万U/ml,较优化前提高了83.3%.通过响应面法对发酵培养基配方进行优化研究,采用Plackett-Burman法对8个因素进行了筛选,结果表明,葡萄糖、尿素、磷酸氢二钾、磷酸二氢钾是影响发酵液腈水合酶产量的主效应因子.用最陡爬坡试验及Central composite design设计进一步优化,利用Design-Expert软件进行二次回归分析,得到各因素的最佳浓度为:葡萄糖22.62g/L、尿素9.76g/L、K2HP04 1.22g/L、KH2PO41.268g/L.在此培养基优化配方下融合子腈水合酶的活力达到1280万U/ml,较原配方的酶活提高了16.4%.  相似文献   

13.
以快生型大豆根瘤菌HH103菌株为供试菌株,采用单因素碳氮源利用试验和正交设计试验,确定最佳培养基及其配方。结果表明:该菌株在YMA中生长良好,最佳碳源为蔗糖,最佳氮源为酵母膏,最佳培养基成分配方(g/L):蔗糖11,酵母膏0.9,K2HPO4 0.5,MnSO4 0.005,CaCl2 0.1,KH2PO4 0.5,MgSO4 0.2,KNO30.77,(NH4)2HPO4 0.33,FeCl3 0.005,pH 7.2。  相似文献   

14.
The basal cut end of coppice shoot cuttings of Pongamia pinnata was treated for 24 h with 0 (water treated control) or 5.0 mmol/L of KMnO4, KCI, and KH2PO4 or 2.5 mmol/L of K2HPO4 and K2SO4. Inorganic salts of P, S, Cl and Mn significantly influenced IAA ionization and adventitious rhizogenesis. P and S salts had lower IAA ionization potential, but more pronounced effect on adventitious rhizogenesis than Cl and Mn salts. The linear regression analysis also established negative correlations between salt induced IAA ionization with various characteristics of adventitious rhizogenesis such as sprouting (r = -0.83, p < 0.05), rooting (r = -0.82, p < 0.05), root number (r = -0.95, p < 0.01), and root length (r = -0.80, p < 0.1). The implication of IAA ionization in adventitious rhizogenesis has been discussed and the possible role of inorganic salts therein suggested.  相似文献   

15.
米根霉发酵生产L-乳酸   总被引:11,自引:0,他引:11  
报道了L-乳酸菌株的分离与筛选,探讨了不同碳源、氮源、通气量、温度等发酵条件对产L-乳酸的影响,从78株米根霉中筛选出13株产L-乳酸较高的菌株,其中米根霉(Rhizopus oryzae)Rs928产L-乳酸最高,产酸最稳定。试验结果表明,该菌株最适发酵培养组成(%):淀粉水解糖16,MgSO4 0.08,KH2PO4 0.05,ZnSO4 0.01,CaCO3 7,pH自然。在60t发酵罐中,  相似文献   

16.
目的:提高酵母产γ-氨基丁酸的能力。方法:采用单因素及正交设计实验对酵母产γ-氨基丁酸(GABA)的培养基进行优化。结果:确定最适碳源为葡萄糖,最佳氮源为蛋白胨和硫酸铵复合氮源,合适的无机盐为KH2PO4;最佳发酵培养基为3%葡萄糖,3%蛋白胨,0.3%(NH4)2SO4和0.1%KH2PO4。在此培养条件下,摇瓶发酵可以获得1.690g.L-1的GABA产量。结论:发酵培养基的优化,提高了菌株产γ-氨基丁酸的能力。  相似文献   

17.
Volume 61, no. 2, p. 419, column 1, lines 15-19: this sentence should read as follows. "The alcohol dehydrogenase and glucose dehydrogenase have a common region reported to be related to pyrroloquinoline quinone binding (2, 10), but SNDH does not contain such a region, indicating that SNDH is not a quinoprotein." Page 419, column 2, line 12: "(Table 4)" should read "(Table 3)." [This corrects the article on p. 413 in vol. 61.].  相似文献   

18.
This paper is concerned with optimization of the fermentation conditions for preparation of alkaline pectin lyase (poly-galacturonic acid trans-eliminase, PATE) by Erwinia carotovora IFO3830 (E.C.IFO3830). The orthogonal matrix method was adopted as the experimental design method for media. The effects of media composition on the growth rate of E.C.IFO3830 are in the order of pectin > KH(2)PO(4)/Na(2)HPO(4) > MgSO(4) > (NH(4))(2)SO(4) > glucose > L-glutamate sodium, and those on PATE activity are in the order of glucose > pectin > L-glutamate sodium > KH(2)PO(4)/Na(2)HPO(4) > MgSO(4) > (NH(4))(2)SO(4). The strain of E.C.IFO3830 grows quickly and easily near an initial pH of 7.0, and especially at the alkaline range of pH 7.0-8.0. The growth rate profiles indicate that E.C.IFO3830 grows very quickly; its generation time t(1/2) is about 0.2 h. The appropriate fermentation period is about 10-20 h for a high level productivity of biomass and 25-35 h for high productivity of PATE enzyme.  相似文献   

19.
Volume 61, no. 4, p. 1478, Table 2, column 4: The diameters (in milliliters) of the zones of inhibition for 5-(mu)g methicillin disks given (from top to bottom), "116," "72," "107," and "32," should read "33.5," "22.6," "34.2," and "21.0," respectively. [This corrects the article on p. 1475 in vol. 61.].  相似文献   

20.
聚乙烯醇降解酶产生菌的分离的发酵条件   总被引:1,自引:0,他引:1  
肖长生  张武 《微生物学报》1989,29(5):343-347
A bacterium D8 strain which high efficiently degrading PVA was isolated from waste water of factory. The strain possesses the abilities of completely degrading 0.5 per cent of PVA (500, 1700) included in the culture medium for four days. It was identified Pseudomonas pseudoalcaligenes. Fermentation conditions of the strain have been investigated. The suitable medium consisted of PVA 1.5% (NH4)2SO40.1%, K2HPO4 0.24%, KH2PO4 0.04%, MgSO4.7H2O 0.035%, NaCl 0.01%, FeSO4 0.001%, yeast extract 0.15%, pH 7.5. The optimal condition for enzyme production are as follows: 250 ml shake filled with 30 ml medium, 30 degrees C, 160n/min incubation period 72 h. Under such conditions enzyme activity is highest.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号