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.

Optimization of Rooting Medium for Tissue Culture Seedlings of Dendrobium officinale by Response Surface Methodology

[Objectives] To increase the survival rate of tissue culture seedlings of Dendrobium officinale,and optimize the conditions of rooting medium by the response surface methodology( RSM). [Methods]The effects of 6-BA concentration,NAA concentration,potato amount and the amount of mashed banana on the growth of seedlings were determined by single factor experiment and were analyzed by Box-Behnken design and response surface methodology. [Results]The optimal culture conditions: rooting medium 1/2 MS + 6-BA 0. 24 mg/L + mashed banana 87. 63 g/L + potato 89. 30 g/L + NAA 0. 52 mg/L + sucrose 20. 0 g/L + activated carbon 4. 0 g/L + agar 7. 0 g/L,p H 5. 8,and light intensity 2 000 Lx. [Conclusions]The model established by response surface methodology has a good predictability and could be used to optimize the conditions of tissue culture and rooting medium of D. officinale.

Improved elastase production by Bacillus sp. EL31410—further optimization and kinetics studies of culture medium for batch fermentation

An efficient culture medium producing a bacterial elastase with high yields was developed further following preliminary studies by means of response surface method. Central composite design (CCD) and response surface method-ology were applied to optimize the medium constituents. A central composite design was used to explain the combined effect of three medium constituents, viz, glucose, K2HPO4, MgSO47H2O. The strain produced more elastase in the completely optimized medium, as compared with the partially optimized medium. The fitted model of the second model, as per RSM, showed that glucose was 7.4 g/100 ml, casein 1.13 g/100 ml, corn steep flour 0.616 g/100 ml, K2HPO4 0.206 g/100 ml and MgSO47H2O 0.034 g/100 ml. The fermentation kinetics of these two culture media in the flask experiments were analyzed. It was found that the highest elastase productivity occurred at 54 hours. Higher glucose concentration had inhibitory effect on elastase production. At the same time, we observed that the glucose consumption rate was slow in the completely optimized medium, which can explain the lag period of the highest elastase production. Some metal ions and surfactant additives also affected elastase production and cell growth.

Optimization for Production of Intracellular Polysaccharide from Cordyceps ophioglossoides L2 in Submerged Culture and Its Antioxidant Activities in vitro

Cordyceps ophioglossoides is a valuable traditional medicinal material.We have found that intracellular polysaccharide(IPS) is the major biologically active ingredient in Cordyceps ophioglossoides.This study is the first time to optimize the yield of IPS from Cordyceps ophioglossoides.The optimal medium for IPS production consists of glucose 54.50 g·L·1,yeast powder 25.50 g·L·1,NaH2PO4 0.4 g·L·1 and K2HPO4 0.4 g·L·1.The suggested culture conditions are 24 ℃,initial pH 4.5 with a rotary speed of 120 r·min·1 for 168 h.The yield of IPS is 737.93 mg·L·1,which is 50% higher than the yield under the conditions prior to optimization.The anti-oxidative activities of IPS in Cordyceps ophioglossoides L2 are also characterized using various in vitro assay.The anti-oxidative activity may explain the reason why IPS from Cordyceps ophioglossoides can be used to fight against neurodegenerative dis-eases and menopausal symptoms.

Impact of Characteristic Culture on the Optimization of Rural Tourism Industry

Based on current rural tourism development of China and its typical modes,this paper on the basis of studying significance and impact of characteristic culture on rural tourism proposes the concept of"integrating characteristic culture and rural tourism,elaborates significance of attractive force of folk cultures,expressive power of vernacular cultures,appeal of characteristic cultures for the optimization of rural tourism industry.

Optimization of Isolation and Culture of Protoplasts in Alfalfa (<i>Medicago sativa</i>) Cultivar Regen-SY

Alfalfa (Medicago sativa) is an important forage crop belonging to the Fabaceae family. It is cultivated across the world for fodder and originated in Asia. Alfalfa cultivar Regen-SY was used in this study which is a hybrid of first-generation self-parents from Regen-S (M. sativa) and Regen-Y (Medicago falcata) research cultivars. The main objective of the study was to optimize conditions for the isolation and liquid culture of alfalfa Regen-SY protoplasts. Several factors like enzyme combination, incubation time, plant age, centrifugation speed and shaker speed affecting protoplast isolation and culture were optimized in the study. The yield and viability of the protoplasts was determined by using hemocytometer and Fluorescein diacetate (FDA) staining respectively. Results showed that factors like enzyme combination, incubation time, plant age, centrifugation speed and Mannitol concentration significantly (p ≤ 0.05) affect protoplast yield and viability whereas shaker speed didn’t result in any significant difference in the yield and viability of protoplasts. Using optimum conditions protoplasts were cultured in the liquid medium and microcalli formation was achieved after five weeks of the culture. The protocol established in this study will assist researchers in the isolation and culture of protoplasts in alfalfa and will accelerate the research processes like protoplast fusion and genetic engineering.

Optimization of Suspension Culture Conditions for Hairy Roots of Aconitum coreanum(Levl.) Raipaics

[ Objective] This study aimed to establish an optimized suspension culture for hairy roots of Aconitum coreanum （Levi.） Raipaics. [ Method ] Hairy root of Aconitum coreanum （ Levl. ） Raipaics A0489 was selected as experimental material, to screen the optimal medium for suspension culture. [ Result] Aconitum coreanum （Levl.） Raipaics hairy roots showed different growth conditions in various liquid medium; salt concentration, nitrogen content, sugar content, rotation speed and room temperature had great influences on the growth of Aconitum coreanum （Levi.） Raipaics hairy roots. [ Conclusion] The optimal suspension culture system for Aconitum coreanum （ Levi. ） Raipaics hairy roots was established ： B5 was used as basic medium, culture temperature was 20℃ under dark conditions, rotation speed was 140 r/m in the first 15 d and 110 r/m in the latter 15 d.

Optimization of Culture Components for Laccase Activity from Pleurotus Ostreatus P40 Using Response Surface Methodology

High enzymatic activity is required for laccase applications.Central composite design （CCD）-based response surface methodology （RSM） can effectively increase the enzymatic activity of Pleurotus ostreatus P40 in liquid substrate fermentation.Initial screening of the nutritional components was performed using a Plackett-Burman design.The variables,namely,bran,bagasse,Tween 80,and yeast extract,were found to have statistically significant effects on laccase activity.These variables were further optimized using CCD-based RSM.Optimal concentrations for the maximum laccase activity were 8.144 2 g/L bran,50 g/L bagasse,0.424 1 mL/L Tween 80,and 2.832 5 g/L yeast extract.Under optimized conditions,the maximum measured laccase activity reached 96 480 U/L,which was close to the predicted value （104 830 U/L） by RSM.Therefore,RSM can be used to optimize culture components for laccase activity from Pieurotus ostreatus P40.

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.

The Optimization and Thinking about Traditional Living Environment of the Tibetan Gongbu Culture——In the Case of Juemu Village on the Side of the Niyang River

Based on the problems of traditional living environment of the Tibetan Gongbu culture and the concept of inheriting the Tibetan Gongbu culture and the harmonious coexistence of environment and human,living environment design of Juemu Village on the side of the Niyang River is optimized. It adheres to the importance of traditional culture,and especially emphasizes the layout of buildings with Tibetan style and their surrounding,function optimization,and the plant design,thereby exploring and attempting planning method of Tibetan living environment under the background of new rural construction.

Strain and Culture Medium Optimization for Production Enhancement of Prodiginines from Marine-Derived Streptomyces sp. GQQ-10

A mutant (GQQ-M6) of a Sponge-Derived streptomyces sp. GQQ-10 obtained by UV-induced mutation was used for producing prodiginines (PGs). Single factor experiments and orthogonal array design (OAD) methods were employed for medium optimization. In the single factor method, the effects of soluble starch, glucose, soybean flour, yeast extract and sodium acetate on PGs production were investigated individually. In the subsequent OAD experiments, the concentrations of these 5 key nutritional components combined with salinity were further adjusted. The mutant strain GQQ-M6 gave a 2.2-fold higher PGs production than that of the parent strain; OAD experiments offered a PGs yield of 61mg L-1, which was 10 times higher than that of the initial GQQ-10 strain under the original cultivation mode.

Effects of Fed-batch and Nitrogen-deficient Culture on Lipid Yield of Chlorella sp.

[Objective] This study was to realize high-density culture of Chlorella sp. as well as the culture with high lipid yield. [Method] Through analyzing the growth curve of Chlorella sp. cells, dextrose consumption curve, change curves of pH and dissolved oxygen, a fed-batch culture was conducted, followed by a nitrogen-deficient culture aiming at accumulating the lipids in Chlorella sp. cells when a high density of Chlorella sp. cells was obtained. [Result] After four batches of feeding were pro- vided, the biomass of Chlorella sp. reached up to 65.25 g/L, and the lipid content increased from 42.75% to 63.82% in Chlorella sp. cells, with the yield of 43.37 g/L in the following 12 hours of nitrogen-deficient culture. [Conclusion] Reasonable fed- batch can significantly improve the biomass of Chlorella sp., and the nitrogen-defi- cient culture further raises the lipid yield of Chlorella sp.

Run-to-run Optimization for Fed-batch Fermentation Process with Swarm Energy Conservation Particle Swarm Optimization Algorithm

An iterative optimization strategy for fed-batch fermentation process is presented by combining a run-to-run optimization with swarm energy conservation particle swarm optimization (SEC-PSO). SEC-PSO, which is designed with the concept of energy conservation, can solve the problem of premature convergence frequently appeared in standard PSO algorithm by partitioning its population into several sub-swarms according to the energy of the swarm and is used in the optimization strategy for parameter identification and operation condition optimization. The run-to-run optimization exploits the repetitive nature of fed-batch processes in order to deal with the optimal problems of fed-batch fermentation process with inaccurate process model and unsteady process state. The kinetic model parameters, used in the operation condition optimization of the next run, are adjusted by calculating time-series data obtained from real fed-batch process in the run-to-run optimization. The simulation results show that the strategy can adjust its kinetic model dynamically and overcome the instability of fed-batch process effectively. Run-to-run strategy with SEC-PSO provides an effective method for optimization of fed-batch fermentation process.

Process Control for Production of Human-like Collagen in Fed-batch Culture of Escherichia coli BL 21

Recombinant E. coli BL 21 was cultivated in high cell density to produce human-like collagen. The effects of the feeding of nitrogen source, controlled by an auto on/off-feeding mode with two different cycles of 0.5min and 4min intervals, oxygen-enrichment methods and inducement strength on the cell yield and human-like collagen production were investigated. The studies showed that nitrogen source feeding in fast cycle could result in higher human-like collagen production than that in slow cycle; and the feedback regulation of glucose, increase of the pressure of fermentation bioreactor, and supply of oxygen-enriched air could all increase cell yield and human-like collagen production. The effects of inducement strength on protein expression were found important. When OD600 reached 90-100, the cultivation temperature was increased to 42℃ to begin induction for 2-3 h, and then shifted to 39℃ for 5-6h induction, the cell density and human-like collagen production could reach 96g·L-1 [DCW (dry cell mass)] and 19.8% (g·g-1 DCW) respectively.

Non-dominated sorting culture differential evolution algorithm for multi-objective optimal operation of Wind-Solar-Hydro complementary power generation system

Due to the intermittency and instability of Wind-Solar energy and easy compensation of hydropower, this study proposes a Wind-Solar-Hydro power optimal scheduling model. This model is aimed at maximizing the total system power generation and the minimum ten-day joint output. To effectively optimize the multi-objective model, a new algorithm named non-dominated sorting culture differential evolution algorithm(NSCDE) is proposed. The feasibility of NSCDE was verified through several well-known benchmark problems. It was then applied to the Jinping Wind-Solar-Hydro complementary power generation system. The results demonstrate that NSCDE can provide decision makers a series of optimized scheduling schemes.

Cultural Binary Particle Swarm Optimization Algorithm and Its Application in Fault Diagnosis

Binary particle swarm optimization algorithm(BPSOA) has the excellent characters such as easy to implement and few set parameters.But it is tendentious to stick in the local optimal solutions and has slow convergence rate when the problem is complex.Cultural algorithm(CA) can exploit knowledge extracted during the search to improve the performance of an evolutionary algorithm and show higher intelligence in treating complicated problems.So it is proposed that integrating binary particle swarm algorithm into cultural algorithm frame to develop a more efficient cultural binary particle swarm algorithm (CBPSOA) for fault feature selection.In CBPSOA,BPSOA is used as the population space of CA;the evolution of belief space adopts crossover,mutation and selection operations;the designs of acceptance function and influence function are improved according to the evolution character of BPSOA.The tests of optimizing functions show the proposed algorithm is valid and effective.Finally,CBPSOA is applied for fault feature selection.The simulations on Tennessee Eastman process (TEP) show the CBPSOA can perform better and more quickly converge than initial BPSOA.And with fault feature selection,more satisfied performance of fault diagnosis is obtained.

Optimized Composition of Functional Bacteria for Bioremediation of Sediment Environment of Shrimp Culture

After the single-strain abilities of organic-pollutant-degrading bacteria in bioremediation of sediment environment of shrimp culture are determined, the multi- strain degrading effect of the compositions of different strains is measured. The results indicate that the multi-strains groups have higher degrading ability than the single -strain groups. Three-strain groups are better than two-strain groups, and four-strain groups are better than three-strain groups and five-strain groups, the groups composed of strains Lt7222, Lt7511, Fc6308 and Gy7018 has the best degrading effect, the CODMn removal rate is 73.2 % in 66 h, and gets to 82.7 % in 114 h, 30 % higher than that of the best single-strain group; Groups of Lt7222, Lt7511, Lt7451 and Gy7018 are the second, whose CODMn removal rate is 82.1 % in 114 h. It is suggested that multi-species bacteria be used as functional bacteria in bioremediation of mariculture environment.

Optimization of IBRS-2 Cells Culturing Conditions for Cultivation of Porcine Parvovirus N Strain Using Roller Bottle

The aim was to optimize the roller bottle culture system of IBRS-2 cells for cultivation of porcine parvovirus （PPV） N strain using a four-factor three-level or- thogonal test （cell culture medium pH value： 7.0, 7.2 and 7.4; inoculation time： 0, 24 and 48 h; inoculation dose： 0.10%, 1.00% and 10.00%; harvest time： 48, 72 and 96 h）. The results showed that the optimal conditions were as follows： cell culture medium pH value of 7.2, synchronous inoculation, inoculation dose of 0.10% and culture time of 96 h. Among the four factors, culture time was the most important factor affectina the virulence titer of PPV N strain.

A novel 3-layer mixed cultural evolutionary optimization framework for optimal operation of syngas production in a Texaco coal-water slurry gasifier

Optimizing operational parameters for syngas production of Texaco coal-water slurry gasifier studied in this paper is a complicated nonlinear constrained problem concerning 3 BP(Error Back Propagation) neural networks. To solve this model, a new 3-layer cultural evolving algorithm framework which has a population space, a medium space and a belief space is firstly conceived. Standard differential evolution algorithm(DE), genetic algorithm(GA), and particle swarm optimization algorithm(PSO) are embedded in this framework to build 3-layer mixed cultural DE/GA/PSO(3LM-CDE, 3LM-CGA, and 3LM-CPSO) algorithms. The accuracy and efficiency of the proposed hybrid algorithms are firstly tested in 20 benchmark nonlinear constrained functions. Then, the operational optimization model for syngas production in a Texaco coal-water slurry gasifier of a real-world chemical plant is solved effectively. The simulation results are encouraging that the 3-layer cultural algorithm evolving framework suggests ways in which the performance of DE, GA, PSO and other population-based evolutionary algorithms(EAs) can be improved,and the optimal operational parameters based on 3LM-CDE algorithm of the syngas production in the Texaco coalwater slurry gasifier shows outstanding computing results than actual industry use and other algorithms.