We demonstrate light focusing through scattering media by introducing particle swarm optimization for modulat- ing the phase wavefront. Light refocusing is simulated numerically based on the angular spectrum method an...We demonstrate light focusing through scattering media by introducing particle swarm optimization for modulat- ing the phase wavefront. Light refocusing is simulated numerically based on the angular spectrum method and the circular Gaussian distribution model of the scattering media. Experimentally, a spatial light modulator is used to control the phase of incident light, so as to make the scattered light converge to a focus. The influence of divided segments of input light and the effect of the number of iterations on light intensity enhancement are investigated. Simulation results are found to be in good agreement with the theoretical analysis for light refocusing.展开更多
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 employe...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.展开更多
Due to the scarcity of fossil fuels in the world, there is increasing interest in the commercial production of biodiesel, which leads to obtaining large amounts of glycerol as a byproduct. If not disposed of properly,...Due to the scarcity of fossil fuels in the world, there is increasing interest in the commercial production of biodiesel, which leads to obtaining large amounts of glycerol as a byproduct. If not disposed of properly, glycerol can generate environmental impact. One of the promises, the application of the crude glycerol is the production of citric acid by microbial fermentation. Citric acid is industrially produced by a submerged fermentation process with Aspergillus niger, using sucrose as carbon source, but due to increased demand for citric acid, alternative processes using renewable sources or waste materials as substrates and the cultivation of yeast strains are being studied. The aim of the study was to determine the best culture condition for maximum citric acid synthesis and lower isocitric acid production from crude glycerol through experimental design tool. For this purpose, the yeast strain Yarrowia lipolytica IMUFRJ-50682 was cultivated in nitrogen-limited glycerol-based media. Therefore, glycerol and yeast extract concentrations and agitation speed were evaluated as independent variables. With pure glycerol, the highest citric acid production achieved was 16.5 g/L with an isocitric acid production of 7.7% （in relation to citric acid）. With crude glycerol, citric acid production reduced to 6.7 g/L because of higher biomass yield. Therefore, an increase in the initial carbon to nitrogen molar ratio from 714 to 1,561 was necessary to increase citric acid production to 9.2 g/L, reducing isocitric acid production and to achieve a yield of 0.41 g of citric acid per glycerol consumed. In this condition, less nitrogen source was used, reducing production costs.展开更多
Decreasing the volume of media required to maintain cell viability not only reduces contamination of bioreactors from the upstream process,but may contribute to cost-containment measures in the biopharmaceutical indus...Decreasing the volume of media required to maintain cell viability not only reduces contamination of bioreactors from the upstream process,but may contribute to cost-containment measures in the biopharmaceutical industry.Based on our recent finding that dextran-containing nanocarriers increased CHO cell density up to 20 fold compared to its cellulose-containing microcarrier counterpart(manuscript submitted),we then investigated the possibility of reducing media volume to maintain cell viability,by utilizing the same dextran-based nanocarrier prepared from a self assembling nanoemulsion(SANE)method,and an adherent Chinese hamster ovary(CHO)cell culture line to evaluate media volume requirements.At the same 60 mL volume of media,cell viability after day 3 was 6 fold greater in CHO cells exposed to dextran-containing nanocarriers compared to cellulose-based microcarriers.When CHO cells were exposed to 60 mL of media containing dextran-based nanocarriers compared to 100 mL of media for cellulose-microcarriers,at day 6,cell density was up to 7 fold greater.Similarly,cell lysate protein concentrations at day 6 was nearly 3 fold greater for CHO cells exposed to dextran-containing nanocarriers compared to the cellulose-based microcarriers.Furthermore,nanocarriers had 59%greater glucose concentration,used as a measure of the polymer dextran and cellulose content levels in the nanocarriers and microcarriers,respectively.In conclusion,nanocarriers with increased numbers of dextran molecules,developed in these studies may be useful to further optimize media volume requirements for maximum culture growth.展开更多
Bread staling is defined as physicochemical changes in bread during storage,which results in undesirable changes in bread quality.It has always been one of the serious problems of the industrial sector throughout hist...Bread staling is defined as physicochemical changes in bread during storage,which results in undesirable changes in bread quality.It has always been one of the serious problems of the industrial sector throughout history.At the same time,vegetable waste,including potato peel(PP),is considered a serious problem to the environment.For this reason,PP has been used in this study to increase enzymatic activities of the yeast Saccharomyces cerevisiae,considered to have positive effects on bread quality.The goal of this study is to design a microbial system to facilitate human activities in industry,both joining the production of valuable enzymes by yeasts and recycling PP in the same medium.As a result,in our study,the highest growth rate of S.cerevisiae was recorded in the treatment with 2%PP present in the yeast growth medium.Also,no microbial growth,from baked bread samples,was observed due to proper storage of the loaves of bread in closed nylon bags at 4℃ for the duration of ten days.Moreover,treatments with 4%PP increased cellulase and invertase activities significantly(P<0.05),in comparison to treatments with no peel and with 2%peel.While amylase activity has been increased significantly(P<0.05)in treatment with 2%peel.In conclusion,treatment with 4%peel is recommended for improving enzymatic activity,in general,and bread quality in particular.展开更多
Media engineering and strain improvement are critical aspects of microbial biotechnology playing a vital role in enhancing microbial productivity,and ensuring cost-effective bioprocessing.In this investigation,we opti...Media engineering and strain improvement are critical aspects of microbial biotechnology playing a vital role in enhancing microbial productivity,and ensuring cost-effective bioprocessing.In this investigation,we optimized the various medium components,nutritional condition,and fermentation parameters for the industrial production of phenoxymethylpenicillin or penicillin V(PenV).We have isolated,characterized Penicillium rubens BIONCL P45 strain which initially produced 100 mg/L of PenV.Further,optimization using production medium 4(PM4)comprising lactose,corn steep solids,sodium sulfate,calcium carbonate,and phenoxy acetic acid lead to a significant increase in production,reaching 430 mg/L.Further improvements through response surface methodology(RSM)predicted a production of 646 mg/L,which was experimentally validated at 685 mg/L.Subsequently,mutagenesis studies using UV(ultraviolet)exposure resulted in the UV-65 mutant,which demonstrated a superior performance,achieving 934 mg/L,surpassing the parental strain.These combined strategies lead to a tenfold increase in PenV titer,highlighting their effectiveness in bioprocess development and industrial-scale antibiotic production.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 61178015,11304104 and 61575070
文摘We demonstrate light focusing through scattering media by introducing particle swarm optimization for modulat- ing the phase wavefront. Light refocusing is simulated numerically based on the angular spectrum method and the circular Gaussian distribution model of the scattering media. Experimentally, a spatial light modulator is used to control the phase of incident light, so as to make the scattered light converge to a focus. The influence of divided segments of input light and the effect of the number of iterations on light intensity enhancement are investigated. Simulation results are found to be in good agreement with the theoretical analysis for light refocusing.
基金supported by the National Natural Science Foundation of China (Nos.30973627 and 30772640)the public projects of the State Oceanic Administration (No.2010418022-3)+1 种基金the Program for Changjiang Scholars and Innovative Research Team in University (No.IRT0944)the Natural Science Fund of Shandong Province,P.R.China (No.ZR2009CZ016)
文摘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.
文摘Due to the scarcity of fossil fuels in the world, there is increasing interest in the commercial production of biodiesel, which leads to obtaining large amounts of glycerol as a byproduct. If not disposed of properly, glycerol can generate environmental impact. One of the promises, the application of the crude glycerol is the production of citric acid by microbial fermentation. Citric acid is industrially produced by a submerged fermentation process with Aspergillus niger, using sucrose as carbon source, but due to increased demand for citric acid, alternative processes using renewable sources or waste materials as substrates and the cultivation of yeast strains are being studied. The aim of the study was to determine the best culture condition for maximum citric acid synthesis and lower isocitric acid production from crude glycerol through experimental design tool. For this purpose, the yeast strain Yarrowia lipolytica IMUFRJ-50682 was cultivated in nitrogen-limited glycerol-based media. Therefore, glycerol and yeast extract concentrations and agitation speed were evaluated as independent variables. With pure glycerol, the highest citric acid production achieved was 16.5 g/L with an isocitric acid production of 7.7% （in relation to citric acid）. With crude glycerol, citric acid production reduced to 6.7 g/L because of higher biomass yield. Therefore, an increase in the initial carbon to nitrogen molar ratio from 714 to 1,561 was necessary to increase citric acid production to 9.2 g/L, reducing isocitric acid production and to achieve a yield of 0.41 g of citric acid per glycerol consumed. In this condition, less nitrogen source was used, reducing production costs.
文摘Decreasing the volume of media required to maintain cell viability not only reduces contamination of bioreactors from the upstream process,but may contribute to cost-containment measures in the biopharmaceutical industry.Based on our recent finding that dextran-containing nanocarriers increased CHO cell density up to 20 fold compared to its cellulose-containing microcarrier counterpart(manuscript submitted),we then investigated the possibility of reducing media volume to maintain cell viability,by utilizing the same dextran-based nanocarrier prepared from a self assembling nanoemulsion(SANE)method,and an adherent Chinese hamster ovary(CHO)cell culture line to evaluate media volume requirements.At the same 60 mL volume of media,cell viability after day 3 was 6 fold greater in CHO cells exposed to dextran-containing nanocarriers compared to cellulose-based microcarriers.When CHO cells were exposed to 60 mL of media containing dextran-based nanocarriers compared to 100 mL of media for cellulose-microcarriers,at day 6,cell density was up to 7 fold greater.Similarly,cell lysate protein concentrations at day 6 was nearly 3 fold greater for CHO cells exposed to dextran-containing nanocarriers compared to the cellulose-based microcarriers.Furthermore,nanocarriers had 59%greater glucose concentration,used as a measure of the polymer dextran and cellulose content levels in the nanocarriers and microcarriers,respectively.In conclusion,nanocarriers with increased numbers of dextran molecules,developed in these studies may be useful to further optimize media volume requirements for maximum culture growth.
文摘Bread staling is defined as physicochemical changes in bread during storage,which results in undesirable changes in bread quality.It has always been one of the serious problems of the industrial sector throughout history.At the same time,vegetable waste,including potato peel(PP),is considered a serious problem to the environment.For this reason,PP has been used in this study to increase enzymatic activities of the yeast Saccharomyces cerevisiae,considered to have positive effects on bread quality.The goal of this study is to design a microbial system to facilitate human activities in industry,both joining the production of valuable enzymes by yeasts and recycling PP in the same medium.As a result,in our study,the highest growth rate of S.cerevisiae was recorded in the treatment with 2%PP present in the yeast growth medium.Also,no microbial growth,from baked bread samples,was observed due to proper storage of the loaves of bread in closed nylon bags at 4℃ for the duration of ten days.Moreover,treatments with 4%PP increased cellulase and invertase activities significantly(P<0.05),in comparison to treatments with no peel and with 2%peel.While amylase activity has been increased significantly(P<0.05)in treatment with 2%peel.In conclusion,treatment with 4%peel is recommended for improving enzymatic activity,in general,and bread quality in particular.
基金supported by Council of Scientific and Industrial Research-Focused Basic Research(CSIR-FBR)scheme,New Delhi,India(Project No-MLP101126).
文摘Media engineering and strain improvement are critical aspects of microbial biotechnology playing a vital role in enhancing microbial productivity,and ensuring cost-effective bioprocessing.In this investigation,we optimized the various medium components,nutritional condition,and fermentation parameters for the industrial production of phenoxymethylpenicillin or penicillin V(PenV).We have isolated,characterized Penicillium rubens BIONCL P45 strain which initially produced 100 mg/L of PenV.Further,optimization using production medium 4(PM4)comprising lactose,corn steep solids,sodium sulfate,calcium carbonate,and phenoxy acetic acid lead to a significant increase in production,reaching 430 mg/L.Further improvements through response surface methodology(RSM)predicted a production of 646 mg/L,which was experimentally validated at 685 mg/L.Subsequently,mutagenesis studies using UV(ultraviolet)exposure resulted in the UV-65 mutant,which demonstrated a superior performance,achieving 934 mg/L,surpassing the parental strain.These combined strategies lead to a tenfold increase in PenV titer,highlighting their effectiveness in bioprocess development and industrial-scale antibiotic production.
