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1.
研究了几种促进剂和前体对红酵母RY-98类胡萝卜素发酵的影响,从中选出了番茄汁、花生油和核黄素3种对红酵母生长及类胡萝卜素合成具有显著促进作用的发酵助剂,并确定了适宜的用量。应用试验和发酵过程动态分析表明,这3种发酵助剂增产效果明显。当同时添加番茄汁3mL/L、花生油1.2mL/L和核黄素3.5mg/L时,菌体量、类胡萝卜素质量分数和产量可分别比对照组提高39.4%、32.8%和85.1%,且对发酵过程菌体生长及生理代谢规律无不良影响。  相似文献   

2.
作者通过革兰氏染色、鞭毛染色、扫描电镜对一株光合细茵进行了形态学特征观察,并通过平板培养、液体培养特征、生理生化试验来了解其培养特征和生理生化特征;同时还通过双光束紫外一可见光谱仪分析了其活体细胞和细胞色素的光谱吸收行为.研究了其产类胡萝卜素的培养基和培养条件,并通过高效液相色谱仪对类胡萝卜素成分进行了分析.结果表明,此菌株为革兰氏阴性、有极生鞭毛,细胞为杆形,有集束生长的习惯,不对称出芽分裂,细胞大小为(0.6~2.5)μm×(0.6~5.0)μm;单茵落在固体平板培养基上呈淡黄色,表面光滑湿润,边缘整齐;在液体培养基上的培养物为深红色;对氨基苯甲酸、酵母浸出物对菌株的生长有显著刺激作用;菌体细胞色素含有类胡萝卜素和叶绿素a.根据这些形态学和生理生化特征,初步确定该菌株为沼泽红假单胞菌(Rhod0PsPdomonas palustris).此茵在培养基组成为(g/L):KHz PO4 0.6,K2 HPO4 0.9,醋酸钠2.0,氯化铵1.5,酵母浸膏0.5,NaCl 0.5,硫酸镁0.3,氯化钙0.2.在28℃、1 500 lx,pH6.5~8.5条件下培养能够快速生长繁殖.通过HPLC分析表明:类胡萝卜素提取液中成分至少有10种,其中5种是主要成分.  相似文献   

3.
应用低水活度选择性增殖的方法从花卉、果园土壤、水果和蜂产品等样品中分离得到267株耐高渗酵母,其中206株生产阿拉伯醇、赤藓糖醇和甘油等各种多元醇.对随机挑选的62株产多元醇的耐高渗酵母在不同质量浓度葡萄糖培养基中的生长特征进行了研究,结果显示酵母的耐高渗生长能力与其产多元醇的类别之间存在关联.在所调查的酵母中,产赤藓糖醇的酵母耐高渗生长能力最强、产阿拉伯醇的酵母耐高渗生长能力次之,产甘油的酵母耐高渗生长能力较弱.  相似文献   

4.
采用贮藏试验对碱法破壁酵母类胡萝卜素的稳定性进行了研究。结果表明,不同贮藏条件下,酵母色素连续以两个速度常数不同的一级方程进行降解(k1〉k2)。第一个一级反应主要反映受损脂肪粒中类胡萝卜紊的变化,第二个反应主要反映未受损脂肪粒中类胡萝卜素的变化。比较不同贮藏条件下的试验结果及各个动力学方程的速度常数,表明采用低温、避光、隔氧及添加抗氧化剂有利于提高酵母色素的存留率,而酵母水分(〈12%)及矿物盐对之影响不大。  相似文献   

5.
以法夫酵母 (Phaffiarhodozyma)WSS -FF6为产生菌进行摇瓶条件下的类胡萝卜素 (主要为虾青素 )发酵条件研究 .正交试验表明 :葡萄糖质量分数对酵母产色素影响较大 ,在起始 pH值为 6,培养温度 2 2℃ ,葡萄糖 3 .0 %、尿素 0 .1 %、磷酸二氢钾 0 .6%、玉米浆 0 .6%的培养基下经过72h、2 2 0r/min摇瓶发酵 ,其生物量为 6.58mg/mL ,类胡萝卜素产量为 1 4.92 μg/mL ,其中虾青素占 78% .  相似文献   

6.
第 1期红酵母类胡萝卜素发酵助剂的筛选及应用王岁楼 ,刘凤珠 ,高建奇 (1 )……………………………………法夫酵母产虾青素的补料发酵徐学明 ,金征宇 ,刘当慧 (5)…………………………………………………硝酸盐在除磷脱氮中的作用邹华 ,阮文权 ,陈坚 (1 0 )………………………………………………………微波对甲壳素脱乙酰反应的影响张立彦 ,曾庆孝 ,林王旬等 (1 5)……………………………………………有机相酶促合成N 月桂酰 β 氨基丙腈 夏咏梅 ,许志国 ,胡学铮等 (2 0 )……………………………………强碱弱酸两性树脂的合成、结构性能及…  相似文献   

7.
以法夫酵母 (Phaffiarhodozyma)WSS FF6为产生菌进行产虾青素的补料发酵 ,在通气量为 2 5 0L/h、pH =6.0± 0 .5的条件下 ,先流加高糖浓度的培养基 ,后添加 0 .1%乙醇 ,进行分批补料发酵 ,经 130h发酵后 ,生物量与类胡萝卜素产量分别为 2 7.4mg/mL、2 6.12 μg/mL ,生长得率、产物得率及酵母色素质量分数分别为 0 .4 6、0 .4 4和 0 .95  相似文献   

8.
通过离子注入N+ 诱发基因突变 ,从而获得高产类胡萝卜素红酵母菌株RY 3 9,其出产率较出发菌株RY 3提高 76.2 % ;经复筛和传代实验表明 ,该高产菌株遗传性能较为稳定 ,3代平均类胡萝卜素产量提高了 74.0 %、质量浓度达 1 0 .9mg/L .  相似文献   

9.
以一株产甘油假丝酵母为出发菌株 ,采用化学诱变 ,通过玉米浆和外加无机磷组成的磷质量浓度为 3 40mg/L的磷源选择培养基 ,得到了一株发酵时间较原菌株缩短了 8h左右 ,产甘油能力 (甘油产量约为 1 40 g/L ,甘油转化率为 5 6% )和原菌株相似的突变株 ,并研究了突变株的发酵性状 .  相似文献   

10.
运用化学诱变的手段 ,以亚硝基胍为诱变剂 ,以产甘油假丝酵母WL2 0 0 2 5为出发菌株 ,诱变获得 2 7株尿嘧啶缺陷型突变株 .并对所获菌株进行了传代稳定性试验和稳定性试验 ,其中 1# 、2 2 # 、2 3# 、2 5 # 、2 6 # 菌株稳定性优良 ,适宜作为进行酵母转化的带有遗传标记的工具菌株 .同时 ,从所获突变株中选出两株进行生长特性的研究和发酵性能的检测 .研究表明 ,缺陷型菌株的生长速度明显慢于亲株 ,但其产甘油的性状并没有较大的改变 .  相似文献   

11.
Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI2) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI2), TXB2 (stabile metabolite of thromboxane A2) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI2 release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB2 (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI2 release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A2, presumably contributing to hemodynamic stability within 30 min after MT.  相似文献   

12.
Don Dame 《Artificial organs》1996,20(5):613-617
Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.  相似文献   

13.
Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.  相似文献   

14.
Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H2O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg−1 followed by 0.15 mg · kg−1 · h−1, n=8) or verapamil (0.1 mg · kg−1 followed by 0.3 mg · kg−1 · h−1, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.  相似文献   

15.
Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.  相似文献   

16.
Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.  相似文献   

17.
Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg?1 i. v. or midazolam 0.05 mg · kg?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg?1 i. v. and 32 μg · kg?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg?1. The mean ED50s, calculated from dose-response curves, were 5.4 mg · kg?1, 3.9 μg · kg?1 and 0.4 mg · kg?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg?1 i. v. or midazolam 0.05 mg · kg?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg?1 and 8 μg · kg?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.  相似文献   

18.
Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg?1 · min?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min?1 · m?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO2I) and oxygen consumption index (VO2I) were also significantly increased in the dopexamine group (DO2I: from 416±91 to 717±110 ml/m2 · m2; VO2I: from 98±25 to 157±22 ml/m2 · m2), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.  相似文献   

19.
A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.  相似文献   

20.
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