The Effect of Culture Condition on Type 5 Capsular Polysaccharide Production of Staphylococcus aureus from Diary Cattle

[Objective] The effect of different culture conditions on type 5 capsular polysaccharide production of Staphylococcus aureus from diary cattle was studied to provide simple way for CP production and preparation and laid foundation for carrying out new polysaccharide vaccine research. [Method] Staph-ylococcus aureus was isolated from milk sample of sick dairy cattle and capsular polysaccharide serotypes were identified. Type 5 capsular polysaccharide was cultured on BHI,solid columbia and mod110 culture media. Glucose and lactose were taken as carbon sources for every culture media in solid and liquid state. Therefore 9 different culture conditions were taken to study the effect of culture conditions on capsular polysaccharide production. [Result] Different culture conditions indicated that compared with columbia culture media, BHI culture media could decline capsular polysaccharide production and mod110 culture media could increase capsular polysaccharide production. While for same culture media, solid culture media was better for capsular polysaccharide production,meanwhile,taken lactose as carbon source could increase capsular polysaccharide production.

Optimization of the Conditions for Using Sewage to Cultivate Navicula tenera

[ Objective] This study was to improve the biomass of Navicula tenera, and thus to provide reference for achieving the industrial production of Navicula tenera. [Method] The feasibility of using sewage to cultivate Navicula tenera was preliminarily investigated based on the consideration of regional characteristics; and a series of culture conditions including the nutrient source of nitrogen（N）, phosphorus（P）, iron（Fe）, silicon（ Si ） and the salinity in medium for culturing Navicula tenera, were optimized by single factor test and orthogonal design.[Result] The optimized conditions for cultivating Navicula tenera using sewage are as follows： the water from Xiaoerlou Artificial Lake of Nanjing University of Technology as basic solvent; 360 mg/L urea; 150 mg/L N2HPO4 · 12H2O; 50 mg/L ferric citrate; 2 000 mg/L Na2SiO3 · 9H2O; 2.0 mol/L salinity. Navicula tenera was strongly adaptive to sewage and could well uptake the nutrient sources in the sewage. Under the optimized conditions, the culture cost decreased, and meanwhile the biomass of Navicula tenera reached 4. 766 g/L which is 3.57 multiples over original medium and 1.9 multiples over optimized medium No. 1.[ Conclusion] This study laid a foundation for the combination of culturing Navicula tenera in large scale and sewage treatment.

Effect of Different Culture Conditions on Sporulation Quantity of Phytophthora capsici in Capsicum annuum L. var. dactylus M. in Xunhua

[Objective] The paper was to explore the effect of different culture conditions on sporulation quantity of Phytophthora capsici in Capsicum annuum L.var.dactylus M.in Xunhua.[Method] The effects of light hours,pH,medium and temperature on sporulation quantity during isolation and culture process of P.capsici were studied.[Result] The sporulation quantity of P.capsici under the conditions of 24 h/day light,pH 7.0,potato medium（PSA） and 30 ℃ was the largest,and pH,basal medium and temperature had greater impact on sporulation quantity.[Conclusion]The study laid foundation for the study on natural incidence condition of C.annuum in Xunhua.

Traditional conditioning and conditions in professional Malaysian women talk

Cross-cultural differences have often been seen as an element contributing to the variations in speech acts and this has affected the differences in interpretations of meanings. Each individual contributes to this difference as a result of his/her variation in upbringing. His/her values, beliefs, traditions, norms and standards are greatly influenced by his/her culture. Cultural differences are not only seen through tangible artifacts and daily practices, but also in the articulation of thoughts. This paper will present findings from the analysis of ＂lunch-talks＂ data involving four professional Malaysian women from the two dominant ethnic communities in Malaysia： Malay and Chinese. The ＂lunch-talks＂ are free flowing semi-formal discourse events with topics ranging from family to politics to work-related issues. Data were recorded with the informants＇ consent and are then transcribed. Our findings indicate that Malaysian women professionals are open, direct and forward in their talk as a result of the influence of cultural and religious conditioning and conditions. With higher education and wider exposure, they are also less inhibited by traditional norms. It would seem that educational exposure and the level of experience play a role in shifting Malaysian women from being demure to being more forward. Nevertheless, some remnants of traditional, cultural and religious values are interlaced within the forwardness. This study will provide some insights into the role of culture in communication. Evidence is drawn from the way the two ethnic groups perceive, interpret, and maintain respect for each other.

Optimization of Culture Conditions and Medium Composition for the Marine Algicidal Bacterium Alteromonas sp. DH46 by Uniform Design

Harmful algal blooms(HABs) have led to extensive ecological and environmental issues and huge economic losses.Various HAB control techniques have been developed,and biological methods have been paid more attention.Algicidal bacteria is a general designation for bacteria which inhibit algal growth in a direct or indirect manner,and kill or damage the algal cells.A metabolite which is strongly toxic to the dinoflagellate Alexandrium tamarense was produced by strain DH46 of the alga-lysing bacterium Alteromonas sp.The culture conditions were optimized using a single-factor test method.Factors including carbon source,nitrogen source,temperature,initial pH value,rotational speed and salinity were studied.The results showed that the cultivation of the bacteria at 28℃ and 180 r min-1with initial pH 7 and 30 salt contcentration favored both the cell growth and the lysing effect of strain DH46.The optimal medium composition for strain DH46 was determined by means of uniform design experimentation,and the most important components influencing the cell density were tryptone,yeast extract,soluble starch,NaNO3 and MgSO4.When the following culture medium was used(tryptone 14.0g,yeast extract 1.63g,soluble starch 5.0 g,NaNO3 1.6 g,MgSO4 2.3 g in 1L),the largest bacterial dry weight(7.36 g L-1) was obtained,which was an enhancement of 107% compared to the initial medium;and the algal lysis rate was as high as 98.4% which increased nearly 10% after optimization.

Effects of culture conditions on ligninolytic enzymes and protease production by Phanerochaete chrysosporium in air

The production of ligninolytic enzymes and protease by Phanerochaete chrysosporium was investigated under different culture conditions. Different amounts of medium were employed in free and immobilized culture, together with two kinds of medium with different C/N ratios. Little lignin peroxidase （LIP） （〈 2 U/L） was detected in free culture with nitrogen-limited medium （C/N ratio： 56/2.2, in mmol/L）, while manganese peroxidase （MnP） maximum activity was 231 and 240 U/L in 50 and 100 ml medium culture, respectively. Immobilized culture with 50 ml nitrogen-limited medium gave the highest MnP and LiP production with the maximum values of 410 and 721 U/L separately on the day 5; however, flasks containing 100 ml nitrogen-limited medium only produced less MnP with a peak value of 290 U/L. Comparatively, carbon-limited medium （C/N ratio： 28/44, in mmol/L） was adopted in culture but produced little MnP and LiE Medium type had the greatest impact on protease production. Large amount of protease was produced due to glucose limitation. Culture type and medium volume influence protease activity corporately by affecting oxygen supply. The results implied shallow immobilized culture was a possible way to gain high production of ligninolytic enzymes.

Effects of Culture Conditions on Growth and Docosahexaenoic Acid Production from Schizochytrium limacinum

The effects of temperature, initial pH, salinity of culture medium, and carbon and nitrogen sources on growth and doco- sahexaenoic acid (C22 : 6 n-3, DHA) production from Schizochytrium limacinum OUC88 were investigated in the present study. The results revealed that the optimal temperature, initial pH and salinity level of the medium for DHA production were 23℃, 7.0 and 18, respectively. Glucose was proved the best carbon source for the growth and DHA production from S. limacinum. Among the nitrogen sources tested, soybean cake hydrolysate, a cheap by-product, was found to be effective for the accumulation of DHA in S. lima- cinum cells. In addition, increasing the concentration of carbon sources in the medium caused a significant increase in cell biomass; however, accumulation of DHA in cells was mainly stimulated by the ratio of C/N in the medium. Under the optimal culture condi- tions, the maximum DHA yield achieved in flasks was 4.08 g L-1 after 5 d of cultivation.

Effect of cultivating conditions on α-galactosidase production by a novel Aspergillus foetidus ZU-G1 strain in solid-state fermentation

The work is intended to achieve optimum culture conditions of α-galactosidase production by a mutant strain ,Aspergillusfoetidus ZU-GI in solid-state fermentation （SSF）. Certain fermentation parameters involving moisture content, incubation temperature, cultivation period of seed, inoculum volume, initial pH value, layers of pledget, load size of medium and period of cultivation were investigated separately. The optimal cultivating conditions of α-galactosidase production in SSF were 60% initial moisture of medium, 28 ℃ incubation temperature, 18^h cultivation period of seed, 10% inoculum volume, 5.0-6.0 initial pH of medium, 6 layers of pledget and 10 g dry matter loadage. Under the optimized cultivation conditions, the maximum α-galactosidase production was 2037.51 U/g dry matter near the 144th hour of fermentation.

Biological characteristics of marine bacterium S-9801 strain and its culture conditions of pigment production

Strain of Flavobacterium sp.(S-9801),was screened from 207 strains of marine bacteria isolated from the Bohai Sea continental shelf and the Zhujiang Estuary,for its red pigment production.The biological characteristics of strain S-9801 and culture conditions of pigment production have been checked out in this study. The color of the bacterial colony on 2216E medium was from coccineus to rose bengal. Optimum culture conditions were sodium chloride concentration(g/dm3),10～30;pH,3～8;temperature,25～28℃;tryptone and yeast extract as nitrogen sources and glucose as carbon source. Under optimum conditions,pigment accumulation started after 12 h,reaching a maximum rate of synthesis at 36 h.

Optimization of Culture Conditions for Production of Cellulase by a Thermophilic Bacillus Strain

The production of cellulase in Bacillus amyloliquefaciens UNPDV-22 was optimized using response surface methodology （RSM）. Central composite design （CCD） was used to study the interactive effect of culture conditions （temperature, pH, and inoculum） on cellulase activity. Results suggested that temperature and pH all have significant impact on cellulase production. The use of RSM resulted in a 96% increase in the cellulase activity over the control of non-optimized basal medium. Optimum cellulase production of 13 U/mL was obtained at a temperature of 42.24 ℃, pH of 5.25, and inoculum size of 4.95% （v/v） in a fermentation medium containing wheat bran, soybean meal and malt dextrin as major nutritional factors.

Studies on Fermentation Conditions of Antimicrobial Substances Produced by Brevibacillus laterosporus BL-21

[Objective] Brevibacil us laterosporus BL-21 was inhibitory to Gibberel a sanbinetti, Fusarium graminearum Magnaporthe grisea and many other phy-topathogenic fungi. Antimicrobial substances can be increased through optimizing the medium of Brevibacil us laterosporus. [Method] A total of 10 factors were tested for their function of improving antibiotics yield of BL-21 by single-factor test. And the indicative bacterium was screened. [Result] The best indicative bacterium was Al-ternaria solani, the optimum process parameters in shaking flask on fermentation consisted of initial pH of 8.0, culture at 30 ℃, loadage 90 ml/250 ml, rotation 180 r/min, and fermentation time of 48 h. The results also indicated that glucose was the best carbon source for the antibiotics productivity of BL-21, and beef extract was the best nitrogen source. In addition, univalent ion Cl＋ and divalent ion Mn2＋ stimu-lated BL-21 antibacterial active component biosynthesis. [Conclusion] Optimized medi-um is more conducive to produce antimicrobial substances.

Statistical optimization of medium composition and culture condition for the production of recombinant anti-lipopolysaccharide factor of Eriocheir sinensis in Escherichia coli

Anti-lipopolysaccharide factors （ALFs） are important antimicrobial peptides that are isolated from some aquatic species. In a previous study, we isolated ALF genes from Chinese mitten crab, Eriocheir sinensis. In this study, we optimized the production of a recombinant ALF by expressing E. sinensis ALF genes in Eseherichia coli maintained in shake-flasks. In particular, we focused on optimization of both the medium composition and the culture condition. Various medium components were analyzed by the Plackett-Burman design, and two significant screened factors, （NH4）2SO4 and KH2PO4, were further optimized via the central composite design （CCD）. Based on the CCD analysis, we investigated the induction start-up time, the isopropylthio-D-galactoside （IPTG） concentration, the post-induction time, and the temperature by response surface methodology. We found that the highest level of ALF fusion protein was achieved in the medium containing 1.89 g/L （NH4）2SO4 and 3.18 g/L KH2PO4, with a cell optical density of 0.8 at 600 nm before induction, an IPTG concentration of 0.5 mmol/L, a post-induction temperature of 32.7~C, and a post-induction time of 4 h. Applying the whole optimization strategy using all optimal factors improved the target protein content from 6.1% （without optimization） to 13.2%. We further applied the optimized medium and conditions in high cell density cultivation, and determined that the soluble target protein constituted 105% of the total protein. Our identification of the economic medium composition, optimal culture conditions, and details of the fermentation process should facilitate the potential application of ALF for further research.

Biological identification and determination of optimum growth conditions for four species of Navicula

Four species in the genus Navicula were isolated using the serial dilution method. Based on scanning elec-tron microscopy （SEM） and sequence comparisons of two segments of genes （small ribosomal subunit and large subunit of Rubisco）, the species were identified asNavicula perminuta,N. pseudacceptata,N. vara, andN. rhynchocephala. Based on phylogenetic analysis and culture trials,there was a close relationship betweenN. perminutaandN. vara. Growth of these species was evaluated using measurements of optical density at 680 nm （OD680） under various environmental factors. Results showed that the optimum culture conditions were 25°C, 50-100 μmol photons m-2 s-1, pH 8.0, and salinities from 25 to 30. However, the favor-able salinity forN. perminuta was surprisingly high at 35. Nutrient requirement analysis demonstrated that growth ofNavicula depended on the availability of SiO32-. Their relative growth rates （RGR） peaked at the highest tested level （0.25 mmol/L）. The optimal concentrations of NO3-and PO43- were 3.6 mmol/L and 0.18 mmol/L, respectively. Culture of theseNavicula species for abalone or sea cucumber aquaculture should take these factors into consideration.

CLONAL PROLIFERATION AND LONG-TERM CULTURE OF MALIGNANT LYMPHOMA CELLS UNDER SERUM-FREE CULTURE CONDITIONS

We developed a serum-free culture system that promoted the growth of B cell colonies in peripheral blood, bone marrow, lymph nodes and cerebrospinal fluid (CSF) from 7 out of 8 patients with non-Hodgkin's lymphomas of B cell type. The culture cells were pretreated with or without galactose oxi-dase (GO) prior to plating. Colony growth was best supported with BCGF. A moderate increment was observed with rIL-3, as well as rIL-1β and even to a lesser degree, by rlL-2, while B cell stimulating factor-2 (rBCSF-2) and rlL-1β did not show significant activity. rGM-CSF and rG-CSF had little effect, while rM-CSF enhanced the formation of lymphoma colonies. The cells from different patients had different requirements for Staphylococcus aureus protein A and GO pretreatment. It reflected the differences in activation and differentiation status and surface properties of lymphoma cells from different patients. The cells from CSF of one patient were successfully maintained in serum-free culture medium supplemented with 10% BCGF or 5% PHA-LCM for more than 4 months. The long-term culture cells were EBV negative, phenotypically consistent with B cells and gene rearrangements for JH, Kappa and myc. This serum-free culture system allowed extensive analysis of the growth requirements for clonogenic precursors.

Isolation Technology of Single Spore and Optimization of Conidia Culture Condition for Ustilaginoidea virens

The single spores were isolated from chlamydospores of Ustilaginoidea virens with three different maturities by PSA. The isolated single spores were cul- tured on different media at different temperatures under natural light for inducing conidia to explore the optimum isolation technique of single spore and optimum cul- ture condition of conidia. The results showed that the successful isolating rate of single spore from yellow rice false smut balls reached 90.00%. The sporulatina quantities of isolated single spores cultured on PSD and PDB media at 22 -29 ~C （variable temperature under natural light） or 28 ℃ （constant temperature under dark condition） for 12 d were up to 6.3× 107 and 1.1× 106 spore/mL, respectively. PSA was the most effective method to isolate single spores from yellow rice false smut balls of U. virens. The optimum conidia culture condition included PSD or PDB medium, 22 -29℃ or 28℃, natural light and vibration culture. Key words Ustilaginoidea virens; Single spore isolation; Conidia; Culture condition

Optimization of the Culture Conditions for the Endophytic strain 4-3

Bacillus amyloliquefaciens 4-3 is an excellent plant endophyte that can be used as a good raw material for microecological preparations.For this reason,it is important to optimize the culture conditions of this strain.The number of viable bacteria of strain 4-3 in this study was the evaluation index,and the culture conditions of the liquid fermentation were optimized by single factor experiment.The optimized culture condition was as follows:incubating temperature 32°C,initial pH value 7.2,rotation speed 220 r/min,inoculum concentration 3%and incubating 56 h,under which higher concentrations of Bacillus amyloliquefaciens could be obtained.

Studies on culture condition and extracellular hydrolase of psychrophilic bacteria from Arctic sea ice

Arctic sea ice in the polar region provides a cold habitat for microbial community. Arctic sea ice microorganisms are revealed to be of considerable importance in basic research and potential in biotechnological application. This paper investigated the culture condition and extraceIlular hydrolase of 14 strains of different Arctic sea ice bacteria. The results showed that optimal growth temperature of strains is 15 ℃ or 20 ℃. The optimal pH is about 8.0. They hardly grow at acid condition. 3 % NaCl is necessary for better growth. These strains have different abilities in producing amylase, protease, eellulase and lipase. Pseudoalteronomas sp. Bsi429 and Pseudoalteronomas sp. Bsi539 produced both cellulose, protease and lipase. These results provide a basis for further developing and exploiting the cold adapted marine enzyme resources.

Optimization of Streptomyces caelestis Culture Conditions and Preliminarily Determination of Its Antifungal Components

Streptomyces caelestis FAS is an actinomyces strain isolated with Ustilago scitaminea as an indicator. With GAUZE s medium as the basic medium, carbon source and nitrogen source in the medium and ventilation volume were optimized, and the antifungal substances produced by S. caelestis FAS were preliminarily determined through organic solvent extraction and ammonium sulfate precipitation. The results showed that the antifungal components produced by S. caelestis FAS were proteins, and the optimal culture conditions were using corn flour as carbon source and KNO 3 as nitrogen source and culturing in 250 ml triangular flask added with 70 ml of culture medium. The crude protein obtained under these culture conditions had the best antifungal effect with an inhibition zone diameter of 25 mm. This study will provide a scientific basis for further study on the antifungal mechanism and application of S. caelestis FAS.

Effects of nutrients and light intensity on the growth and biochemical composition of a marine microalga Odontella aurita

Algal biotechnology has advanced greatly in the past three decades. Many microalgae are now cultivated to produce bioactive substances. Odontella aurita is a marine diatom industrially cultured in outdoor open ponds and used for human nutrition. For the first time, we have systematically investigated the effects of culture conditions in cylindrical glass columns and fiat-plate photobioreactors, including nutrients （nitrogen, phosphorus, silicon, and sulfur）, light intensity and light path, on O. aurita cell growth and biochemical composition （protein, carbohydrate, β-1,3-glucan, lipids, and ash）. The optimal medium for photoautotrophic cultivation of O. aurita contained 17.65 mmol/L nitrogen, 1.09 mmol/L phosphorus, 0.42 mmol/L silicon, and 24.51 mmol/L sulfur, yielding a maximum biomass production of 6.1-6.8 g/L and 6.7-7.8 g/L under low and high light, respectively. Scale-up experiments were conducted with fiat-plate photobioreactors using different light-paths, indicating that a short light path was more suitable for biomass production of O. aurita. Analyses of biochemical composition showed that protein content decreased while carbohydrate （mainly composed of 15-1,3-glucan） increased remarkably to about 50% of dry weight during the entire culture period. The highest lipid content （19.7% of dry weight） was obtained under 0.11 mmol/L silicon and high light conditions at harvest time. Fatty acid profiles revealed that 80% were Cx4, C^6, and C20, while arachidonic acid and eicosapentaenoic acid （EPA） accounted for 1.6%-5.6% and 9%-20% of total fatty acids, respectively. High biomass production and characteristic biochemical composition profiles make O. aurita a promising microalga for the production ofbioactive components, such as EPA and D-1,3-glucan.

Priming strategies for controlling stem cell fate: Applications and challenges in dental tissue regeneration

Mesenchymal stromal cells(MSCs)have attracted intense interest in the field of dental tissue regeneration.Dental tissue is a popular source of MSCs because MSCs can be obtained with minimally invasive procedures.MSCs possess distinct inherent properties of self-renewal,immunomodulation,proangiogenic potential,and multilineage potency,as well as being readily available and easy to culture.However,major issues,including poor engraftment and low survival rates in vivo,remain to be resolved before large-scale application is feasible in clinical treatments.Thus,some recent investigations have sought ways to optimize MSC functions in vitro and in vivo.Currently,priming culture conditions,pretreatment with mechanical and physical stimuli,preconditioning with cytokines and growth factors,and genetic modification of MSCs are considered to be the main strategies;all of which could contribute to improving MSC efficacy in dental regenerative medicine.Research in this field has made tremendous progress and continues to gather interest and stimulate innovation.In this review,we summarize the priming approaches for enhancing the intrinsic biological properties of MSCs such as migration,antiapoptotic effect,proangiogenic potential,and regenerative properties.Challenges in current approaches associated with MSC modification and possible future solutions are also indicated.We aim to outline the present understanding of priming approaches to improve the therapeutic effects of MSCs on dental tissue regeneration.