Optimization of solid culture conditions for TNF-α inhibitor qiaonanmycin via response surface methodology

目的利用响应面法对潜在的Tnf-α抑制剂桥南霉素固态发酵培养基进行优化。方法用HPlC做检测方法,以桥南霉素的洗脱峰面积为指标,先通过PlACkETT-burMAn(P-b)实验筛选出影响固态发酵产量的主要因素,进而进行单因素优化实验和响应面中心组合设计实验,确定主要影响因素的最佳浓度,得到最优的固体发酵培养基组成。结果优化后的发酵培养基组成:土豆400g/l、葡萄糖35g/l、蛋白胨10.5g/l、(nH4)2SO4 0.6g/l。按此配方固态发酵10l,对得到的粗提物进行HPlC检测,桥南霉素的实际产量为4.3Mg/l,与模型的理论值基本相符,较优化前的产量1.5Mg/l提高了186.7%。结论响应面方法是一种有效的培养基优化方法,经此优化方法桥南霉素的产量得到了较大的提高。Objective The solid fermentation culture conditions of compound qiaonanmycin were optimized via response surface methodology.Methods Based on quantitative detection method of qiaonanmycin by HPLC, the key fermentation factors were determined via P-B test, then their optimized concentrations were confirmed through response face method.Results The optimum solid fermentation culture medium compositions of qiaonanmycin were: potato 400g/L, dextrose 35g/L, peptone 10.5g/L, and(NH4)2SO4 0.6g/L.Under this condition, the yield of qiaonanmycin was 4.3mg/L, resulting in a 186.7% increase comparing with original production yield, and the optimized yield was consistent well with theoretical value predicted by response face method.Conclusion The optimized solid fermentation culture conditions were reliable and repeatable, it was warranted for large-scale fermentation process.中央高校基本业务费(No.2010121092); 厦门市科技计划项目(No.3502Z20123010

不同 pH和盐度下海洋细菌对赤潮藻生长和产毒的影响

研究了在可控生态条件下 ,一株分离自厦门西海域沉积物的海洋细菌S10 在不同pH和盐度条件下对赤潮原因种塔玛亚历山大藻 (Alexandriumtamarense)生长和产毒的影响 .结果表明 ,实验用藻株适宜生长 pH为 6～ 8,适宜盐度为 2 0～ 34;该藻株在不同pH及不同盐度条件下 ,藻细胞毒力差异显著 ,且随着pH升高而下降 ,随着盐度增加而加大 ,到盐度为 30时达到最高值 ,然后逐渐下降 ;菌株S10 (1.0 2× 10 10cells·ml-1)在pH 7～ 9和盐度 15～ 34下均能有效抑藻生长和产毒 ,且在 pH 7、盐度 34时其抑藻生长作用最强 ;在 pH 7时抑藻产毒效果较好 ,且其抑藻产毒作用强度不随盐度变化而异

Effects of marine bacteria on the growth and toxin production of red-tide algae under different pHand salinities

研究了在可控生态条件下,一株分离自厦门西海域沉积物的海洋细菌S10在不同pH 和盐度条件下对赤潮原因种塔玛亚历山大藻( A lexandrium tamarense) 生长和产毒的影响. 结果表明,实验用藻株适宜生长pH 为6～8 ,适宜盐度为20～34 ;该藻株在不同pH 及不同盐度条件下,藻细胞毒力差异显著,且随着pH 升高而下降,随着盐度增加而加大,到盐度为30 时达到最高值,然后逐渐下降;菌株S10 (1. 02 ×1010cells·ml - 1) 在pH 7～9 和盐度15～34 下均能有效抑藻生长和产毒,且在pH 7 、盐度34 时其抑藻生长作用最强;在pH 7 时抑藻产毒效果较好,且其抑藻产毒作用强度不随盐度变化而异.国家重点基础研究发展规划项目(2001CB409710) 和国家自然科学基金资助项目(49676302 ,30200041

Preliminary study on PAH degradation by bacteria from contami-nated sediments in Xiamen Western Sea, Fujian, China

In order to estimate the biodegradation of three polycyclic aromatic hydrocarbons (PAHs) compounds, bacterial strains were isolated from marine sediments in three heavily contaminated sites (Yuandang Lake, Dongdu Port and Aquacultural zones in Maluan Bay) in Xiamen Western Sea. The results show three bacterial strains, which used pyrene as the sole carbon source, were identified as strains of Aureobacterium sp., Arthrobacter sp., Rhodococcus sp. The PAH-degrading bacteria isolated had a strong ability to degrade phenan-hrene, fluoranthene and pyrene at different degradation rates. The highest degradation rate was observed when three PAH compounds were mixed with an individual strain in the medium. The three PAHs were degraded after one week with a degradation rate of 89.94 % for phenanthrene and 93.4 % for both of fluoranthene and pyrene. In addition, after 25 days of incubation, the degradation rate was 99.98 % for phenanthrene and 99.97 % for both of fluoranthene and pyrene. Optical density was measured to ..

试论现代企业的权益计量理论选择

西方会计理论界曾先后提出过业主权论(所有者论)、主体论、剩余权益论、企业论、基金论、指挥者论等多种权益计量理论,其中占主流派地位且在实务中得到广泛运用的是业主权论和主权论。本文试图从产权角度出发分析业主权论和主体论,进而推演出适合目前我国现代企业的权益计量理论

Phase-specific cone beam computed tomography reduces reconstructed volume loss of moving phantom

The accurate volumetric calculation of moving targets/organs is required to use cone-beam computed tomography (CBCT) for replanning purposes. This study was aimed to correct the reconstructed volume losses of moving phantoms by phase-specific CBCT. ;Planning fan-beam CT (FBCT) of five hepatobiliary/gastrointestinal/pancreatic cancer patients were acquired under active breathing control and compared with free-breathing CBCT for kidney volumes. Three different-sized ball phantoms were scanned by FBCT and CBCT. Images were imported to a planning system to compare the reconstructed volumes. The phantoms were moved longitudinally on an oscillator with different amplitudes/frequencies. The phase-specific projections of CBCT for moving phantoms were selected for volume reconstruction. ;The differences in reconstructed volumes of static small, medium, large phantoms between FBCT and CBCT were -aEuro parts per thousand 6.7%, -aEuro parts per thousand 2.3%, and -aEuro parts per thousand 2.0%, respectively. With amplitudes of 7.5-20 mm and frequencies of 8-16 oscillations/min, volume losses on CBCT were comparable with FBCT in large moving phantoms (range 9.1-27.2%). Amplitudes were more subject to volume losses than frequencies. On phase-specific CBCT, volume losses were reduced to 2.3-6.5% by reconstruction using 2-3 projections at end/midoscillation phase. ;Amplitude had more impact than frequency on volume losses of moving phantoms on CBCT. Phase-specific CBCT reduced volume losses

Equalization of Transducers′ Spectral Characteristic in High Speed Data Transmission within Underwater Acoustic Channel

海洋水声信道严重的多途特性造成的码间干扰是水声信道高速率数据传输技术所需克服的最大困难，而接收和发射换能器在所用频带的不平坦又加剧了多途的影响.并详细讨论了克服多途效应造成的码间干扰采取的一项重要措施：换能器频谱特性的均衡技术The key problem to be solved in the underwater high speed data transmission technology is the interference between codes caused by the severe multiple path characteristic in the underwater acoustic channel of the sea, and the uneven spectral characteristic of receiving and transmitting transducer in the frequency band used still exacerbate the influence of the multiple path .In the article, one of the most important measures taken in solving the interference between codes caused by multiple path effect is discussed in details, which is the equalization of transducer spectral characteristic.福建省自然科学基

Isolation,Purification and Characterization of the Secondary Metabolites from an Endophytic Fungus of Camptotheca acuminate

通信作者:[email protected][中文文摘]以一株分离自福建省武夷山自然保护区的喜树内生真菌SXZ-19为研究对象,通过固体平板发酵培养对菌体的化学成分进行了研究.从10L发酵菌体提取物中分离得到8个单体化合物,通过核磁共振以及质谱数据鉴定了化合物1～8的化学结构,分别为:2个线性呋喃聚酮类化合物(1～2);2种真菌毒素(7～8),交链孢酚单甲醚(alternariol monomethyl ether,AME)和交链孢酚(alternariol,AOH);4个洛伐他丁类似物oblongolides D(3),P(4),H(5)和V(6),其中化合物4和5互为差向异构体,为从同一菌株中分离得到oblongolides的差向异构体.[英文文摘]Endophytic microorganisms are a significant reservoir of genetic diversity,and an important source for the discovery of novel bioactive secondary metabolites.In the course of our ongoing efforts to discover potential anticancer agents from endophytic fungi,eight natural compounds,including two linear furanopolyketides (1-2),two Alternariatoxins (7-8),namely alternariol monomethyl ether (AME)and alternariol (AOH),and four lovastatin analogues (oblongolides D (3),P (4),H (5)and V (6)),were isolated from the endophytic fungal strain Diaporthe sp.SXZ-19of Camptotheca acuminate.The strain was collected from National Conservation District Wuyi in Fujian Province,China,and deposited in the laboratory of Microbial Pharmaceutical ngineering,Xiamen University,China.The chemical structure of these compounds were elucidated by spectroscopic analyses including1 H and 13 C-NMR,2D NMR(HMQC,HMBC,1 H-1 H-COSY and NOESY)and ESI-MS.Of these compounds,oblongolides P (4)and H (5)are epimers,which was the first time to report the isolation of two epimers of oblongolides from one strain．科技部国际科技合作项目(2007DFA30970);中央高校基本科研业务费专项(2010121092,2011121037

Study on antimicrobial activities of marine lignicolous fungi

从福建厦门海沧、集美及漳州浮宫等地采集到的红树林等海洋潮间带的各种腐木样品中分离得到176株海洋木栖真菌,对其进行抗菌活性检测.其结果表明共有96株海洋木栖真菌对大肠杆菌、枯草杆菌及白色假丝酵母中的一种或多种拮抗指示菌具有抑制作用,占供测菌株总数的54.5%.在这些活性菌株中,红树源菌株拮抗比例为30.2%,非红树源菌株拮抗比例为69.8%.具有抗菌活性的菌株主要分布于15个属中,包括木霉Trichoderma、青霉Penicillium、拟青霉Paecilomyces和一些不产孢的分类群.某些稀有真菌如盘多毛孢Pestalotia、茎点霉Phoma也具有一定的抗菌活性.One hundred and seventy-six strains of marine lignicolous fungi wereisolated from mangrove debris and other submerged wood panels which were collected from the intertidal zone around Xiamen for detection of the antimicobial activity. The results showed that ninety-six strains of the fungihave antagonism against one or more indicators, such as Escherichia coli,Bacillus subtilis and Candida albicans. The ratio of active fungi to thetotal isolates is 54.5%, which consists of 30.2% from mangrove debris and 69.8%from other materials. The active marine lignicolous fungi were identified as 15genera, most of which belong to Trichoderma sp., Penicillium sp. and Paecilomyces sp. and some sporeless class. Some rare fungi such as Pestalotia sp. and Phomopsis sp. also present a certain antimicrobial activity.国家高技术研究发展计划资助项目(2001AA620401);; 国家自然科学基金资助项目(30070024