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Maria Elisabetta Guerzoni - One of the best experts on this subject based on the ideXlab platform.

  • Growth/no growth interfaces of Bacillus cereus, Staphylococcus aureus and Salmonella enteritidis in model systems based on water activity, pH, temperature and Ethanol Concentration
    Food Microbiology, 2001
    Co-Authors: Rosalba Lanciotti, Milena Sinigaglia, Fausto Gardini, Lucia Vannini, Maria Elisabetta Guerzoni
    Abstract:

    Abstract This study focuses its attention on the boundary between the growth and no growth of three strains of Salmonella enteritidis , Bacillus cereus and Staphylococcus aureus in the presence of growth controlling factors such as temperature, pH, water activity (A w ) and Ethanol Concentration. Preliminarly, the minimal values of pH, A w and temperature, and the maximum Ethanol Concentrations allowing the growth of the considered micro-organisms were determined. The calculation of these values enabled the use of logistic model to evaluate the growth/no growth boundary for the bacteria in relation to the considered independent variables. The location of the growth/no-growth boundaries for S. enteritidis and Staph. aureus were strongly affected, at the same Ethanol Concentration, by temperature, pH and A w . Among the considered species, Staph. aureus was endowed with the highest sensitivity to low pH values while B. cereus's growth/no growth interface, was quite unaffected by the combination of the stresses, when the physico–chemical conditions were above the minimum for growth. The effects of temperature, A w and Ethanol on the limitation of growth of the considered species were not merely additive. It was possible to identify the combinations of such factors preventing the growth of Salmonella enteritidis , Staph. aureus and B. cereus .

  • growth no growth interfaces of bacillus cereus staphylococcus aureus and salmonella enteritidis in model systems based on water activity ph temperature and Ethanol Concentration
    Food Microbiology, 2001
    Co-Authors: Rosalba Lanciotti, Milena Sinigaglia, Fausto Gardini, Lucia Vannini, Maria Elisabetta Guerzoni
    Abstract:

    Abstract This study focuses its attention on the boundary between the growth and no growth of three strains of Salmonella enteritidis , Bacillus cereus and Staphylococcus aureus in the presence of growth controlling factors such as temperature, pH, water activity (A w ) and Ethanol Concentration. Preliminarly, the minimal values of pH, A w and temperature, and the maximum Ethanol Concentrations allowing the growth of the considered micro-organisms were determined. The calculation of these values enabled the use of logistic model to evaluate the growth/no growth boundary for the bacteria in relation to the considered independent variables. The location of the growth/no-growth boundaries for S. enteritidis and Staph. aureus were strongly affected, at the same Ethanol Concentration, by temperature, pH and A w . Among the considered species, Staph. aureus was endowed with the highest sensitivity to low pH values while B. cereus's growth/no growth interface, was quite unaffected by the combination of the stresses, when the physico–chemical conditions were above the minimum for growth. The effects of temperature, A w and Ethanol on the limitation of growth of the considered species were not merely additive. It was possible to identify the combinations of such factors preventing the growth of Salmonella enteritidis , Staph. aureus and B. cereus .

Hiroshi Shimizu - One of the best experts on this subject based on the ideXlab platform.

  • analysis of adaptation to high Ethanol Concentration in saccharomyces cerevisiae using dna microarray
    Bioprocess and Biosystems Engineering, 2009
    Co-Authors: Thai Nho Dinh, Keisuke Nagahisa, Takashi Hirasawa, Chikara Furusawa, Katsunori Yoshikawa, Hiroshi Shimizu
    Abstract:

    In industrial process, yeast cells are exposed to Ethanol stress that affects the cell growth and the productivity. Thus, investigating the intracellular state of yeast cells under high Ethanol Concentration is important. In this study, using DNA microarray analysis, we performed comprehensive expression profiling of two strains of Saccharomyces cerevisiae, i.e., the Ethanol-adapted strain that shows active growth under the Ethanol stress condition and its parental strain used as the control. By comparing the expression profiles of these two strains under the Ethanol stress condition, we found that the genes related to ribosomal proteins were highly up-regulated in the Ethanol-adapted strain. Further, genes related to ATP synthesis in mitochondria were suggested to be important for growth under Ethanol stress. We expect that the results will provide a better understanding of Ethanol tolerance of yeast.

  • Adaptation of Saccharomyces cerevisiae cells to high Ethanol Concentration and changes in fatty acid composition of membrane and cell size.
    PloS one, 2008
    Co-Authors: Thai Nho Dinh, Keisuke Nagahisa, Takashi Hirasawa, Chikara Furusawa, Hiroshi Shimizu
    Abstract:

    Background Microorganisms can adapt to perturbations of the surrounding environment to grow. To analyze the adaptation process of the yeast Saccharomyces cerevisiae to a high Ethanol Concentration, repetitive cultivation was performed with a stepwise increase in the Ethanol Concentration in the culture medium. Methodology/Principal Findings First, a laboratory strain of S. cerevisiae was cultivated in medium containing a low Ethanol Concentration, followed by repetitive cultivations. Then, the strain repeatedly cultivated in the low Ethanol Concentration was transferred to medium containing a high Ethanol Concentration and cultivated repeatedly in the same high-Ethanol-Concentration medium. When subjected to a stepwise increase in Ethanol Concentration with the repetitive cultivations, the yeast cells adapted to the high Ethanol Concentration; the specific growth rate of the adapted yeast strain did not decrease during repetitive cultivation in the medium containing the same Ethanol Concentration, while that of the non-adapted strain decreased during repetitive cultivation. A comparison of the fatty acid composition of the cell membrane showed that the contents in oleic acid (C18:1) in Ethanol-adapted and non-adapted strains were similar, but the content of palmitic acid (C16:0) in the Ethanol-adapted strains was lower than that in the non-adapted strain in media containing Ethanol. Moreover, microscopic observation showed that the mother cells of the adapted yeast were significantly larger than those of the non-adapted strain. Conclusions Our results suggest that activity of cell growth defined by specific growth rate of the yeast cells adapted to stepwise increase in Ethanol Concentration did not decrease during repetitive cultivation in high-Ethanol-Concentration medium. Moreover, fatty acid content of cell membrane and the size of Ethanol-adapted yeast cells were changed during adaptation process. Those might be the typical phenotypes of yeast cells adapted to high Ethanol Concentration. In addition, the difference in sizes of the mother cell between the non-adapted and Ethanol strains suggests that the cell size, cell cycle and adaptation to Ethanol are thought to be closely correlated.

  • fuzzy control of Ethanol Concentration its application to maximum glutathione production in yeast fed batch culture
    Biotechnology and Bioengineering, 1993
    Co-Authors: Catalino G. Alfafara, Keigo Miura, Hiroshi Shimizu, Suteaki Shioya, Kenichi Suga, K. Suzuki
    Abstract:

    A fuzzy logic controller (FLC) for the control of Ethanol Concentration was developed and utilized to realize the maximum production of glutathione (GSH) in yeast fed-batch culture. A conventional fuzzy controller, which uses the control error and its rate of change in the premise part of the linguistic rules, worked well when the initial error of Ethanol Concentration was small. However, when the initial error was large, controller overreaction resulted in an overshoot. An improved fuzzy controller was obtained to avoid controller overreaction by diagnostic determination of glucose emergency states', and then appropriate emergency control actions were implemented. The emergency control action was obtained by the use of weight coefficients and modification of linguistic rules to decrease the overreaction of the controller when the fermentation was in the emergency state. The improved fuzzy controller was able to control a constant Ethanol Concentration under conditions of large initial error.

  • Fuzzy Control of Ethanol Concentration and its Application to Glutathione Production in Yeast Fed-batch Culture
    IFAC Proceedings Volumes, 1992
    Co-Authors: Hiroshi Shimizu, Keigo Miura, Suteaki Shioya, Catalino G. Alfafara, Ken-ich Suga, K. Suzuki
    Abstract:

    Abstract The aim of this article is to develop a fuzzy controller for Ethanol Concentration control in a yeast fed-batch culture. The proposed fuzzy controller can diagnose the state of fermentation and avoid the overfeeding and underfeeding of the substrate. Experimental evidence shows that controller performance is better as compared with PI and conventional fuzzy controllers. This fuzzy control system was applied to the optimal production of glutathione (GSH) in yeast fed-batch culture.

Fei Duan - One of the best experts on this subject based on the ideXlab platform.

  • Octagon to Square Wetting Area Transition of Water–Ethanol Droplets on a Micropyramid Substrate by Increasing Ethanol Concentration
    Langmuir : the ACS journal of surfaces and colloids, 2017
    Co-Authors: Huicheng Feng, Karen S. L. Chong, Kian Soo Ong, Fei Duan
    Abstract:

    The wettability and evaporation of water–Ethanol binary droplets on the substrate with micropyramid cavities are studied by controlling the initial Ethanol Concentrations. The droplets form octagonal initial wetting areas on the substrate. As the Ethanol Concentration increases, the side ratio of the initial wetting octagon increases from 1.5 at 0% Ethanol Concentration to 3.5 at 30% Ethanol Concentration. The increasing side ratio indicates that the wetting area transforms from an octagon to a square if we consider the octagon to be a square with its four corners cut. The droplets experience a pinning–depinning transition during evaporation. The pure water sessile droplet evaporation demonstrates three stages from the constant contact line (CCL) stage, and then the constant contact angle (CCA) stage, to the mixed stage. An additional mixed stage is found between the CCL and CCA stages in the evaporation of water–Ethanol binary droplets due to the anisotropic depinning along the two different axes of symm...

  • octagon to square wetting area transition of water Ethanol droplets on a micropyramid substrate by increasing Ethanol Concentration
    Langmuir, 2017
    Co-Authors: Huicheng Feng, Karen S. L. Chong, Kian Soo Ong, Fei Duan
    Abstract:

    The wettability and evaporation of water–Ethanol binary droplets on the substrate with micropyramid cavities are studied by controlling the initial Ethanol Concentrations. The droplets form octagonal initial wetting areas on the substrate. As the Ethanol Concentration increases, the side ratio of the initial wetting octagon increases from 1.5 at 0% Ethanol Concentration to 3.5 at 30% Ethanol Concentration. The increasing side ratio indicates that the wetting area transforms from an octagon to a square if we consider the octagon to be a square with its four corners cut. The droplets experience a pinning–depinning transition during evaporation. The pure water sessile droplet evaporation demonstrates three stages from the constant contact line (CCL) stage, and then the constant contact angle (CCA) stage, to the mixed stage. An additional mixed stage is found between the CCL and CCA stages in the evaporation of water–Ethanol binary droplets due to the anisotropic depinning along the two different axes of symm...

K. Suzuki - One of the best experts on this subject based on the ideXlab platform.

  • fuzzy control of Ethanol Concentration its application to maximum glutathione production in yeast fed batch culture
    Biotechnology and Bioengineering, 1993
    Co-Authors: Catalino G. Alfafara, Keigo Miura, Hiroshi Shimizu, Suteaki Shioya, Kenichi Suga, K. Suzuki
    Abstract:

    A fuzzy logic controller (FLC) for the control of Ethanol Concentration was developed and utilized to realize the maximum production of glutathione (GSH) in yeast fed-batch culture. A conventional fuzzy controller, which uses the control error and its rate of change in the premise part of the linguistic rules, worked well when the initial error of Ethanol Concentration was small. However, when the initial error was large, controller overreaction resulted in an overshoot. An improved fuzzy controller was obtained to avoid controller overreaction by diagnostic determination of glucose emergency states', and then appropriate emergency control actions were implemented. The emergency control action was obtained by the use of weight coefficients and modification of linguistic rules to decrease the overreaction of the controller when the fermentation was in the emergency state. The improved fuzzy controller was able to control a constant Ethanol Concentration under conditions of large initial error.

  • Fuzzy Control of Ethanol Concentration and its Application to Glutathione Production in Yeast Fed-batch Culture
    IFAC Proceedings Volumes, 1992
    Co-Authors: Hiroshi Shimizu, Keigo Miura, Suteaki Shioya, Catalino G. Alfafara, Ken-ich Suga, K. Suzuki
    Abstract:

    Abstract The aim of this article is to develop a fuzzy controller for Ethanol Concentration control in a yeast fed-batch culture. The proposed fuzzy controller can diagnose the state of fermentation and avoid the overfeeding and underfeeding of the substrate. Experimental evidence shows that controller performance is better as compared with PI and conventional fuzzy controllers. This fuzzy control system was applied to the optimal production of glutathione (GSH) in yeast fed-batch culture.

Zeng Li-chua - One of the best experts on this subject based on the ideXlab platform.

  • Monitoring Ethanol Concentration in CT-guided sclerotherapy of simple hepatic cysts
    Chinese Journal of Interventional Imaging and Therapy, 2014
    Co-Authors: Zeng Li-chua
    Abstract:

    Objective To observe the value of monitoring Ethanol Concentration in CT-guided sclerotherapy of simple hepatic cysts.Methods Clinical data of 48patients with simple hepatic cysts who were treated with CT-guided sclerotherapy were retrospectively analyzed.There were 15cases received therapy without Ethanol Concentration monitoring(general treatment group)and 33cases with Ethanol Concentration monitoring through measurement of CT value(Ethanol monitoring group).Various Concentrations of Ethanol solutions(from 10%to 100%at 10%increments)were scanned with CT.CT values were measured and the correlation between CT value and Ethanol Concentration was analyzed.The efficacy was compared between the two groups 6months after operation.Results There was linear correlation between CT value and Ethanol Concentration(r=-0.983,P0.05).The complete regression and partial response rate was 46.67%(7/15)and26.67%(4/15)for general treatment group,84.85%(28/33)and 15.15%(5/33)for Ethanol monitoring group.The overall success rate was 73.33%(11/15)for general treatment group and 100%(33/33)for Ethanol monitoring group(P0.05).Significant statistical difference of volume reduction rate was found between the two groups([81.98±20.35]%vs[98.37±4.04]%,P0.05).Conclusion There is negative linear correlation between CT value and Ethanol Concentration.Monitoring Ethanol Concentration through measurement of CT can significantly improve therapeutic effect value of CTguided sclerotherapy of simple hepatic cysts.

  • The application of Ethanol Concentration monitoring in CT-guided sclerotherapy for simple renal cysts
    Journal of Interventional Radiology, 2014
    Co-Authors: Zeng Li-chua
    Abstract:

    Objective To evaluate Ethanol Concentration monitoring in performing CT-guided sclerotherapy for simple renal cysts. Methods This study consisted of experimental part and clinical part.For the experimental study, different Concentrations of Ethanol solution(from 10% to 100% at 10%increments) were scanned with CT, and the CT values were determined. The correlation between CT values and Ethanol Concentrations were analyzed. A total of 108 consecutive patients with simple renal cysts were enrolled in the clinical study. The patients were admitted to authors' hospital during the period from Sep.2009 to Aug. 2012 and received sclerotherapy with Ethanol. The patients were divided into group A(n = 40)and group B(n = 68). During the operation Ethanol Concentration monitoring was not employed in patients of group A, while Ethanol Concentration monitoring of the cyst was used in patients of group B. Six months after the treatment, follow-up CT scanning or ultrasound examination were made, and the results were compared between the two groups. Results In the experimental study, a linear correlation existed between the CT values and Ethanol Concentration(r =-0.983, P 0.05). In the clinical study, the complete regression rate,partial regression rate and overall success rate of group A were 57.5%(23/40), 22.5%(9/40) and 80%(32/40) respectively, and those of group B were 82.4%(56/68), 17.6%(12/68) and 100%(68/68) respectively.The differences in complete regression rate and overall success rate between group A and group B were statistically significant(P 0.05). Conclusion The experimental study indicates that a linear correlation exists between CT values and Ethanol Concentrations. With the help of Ethanol Concentration monitoring, CT-guided sclerotherapy can significantly improve the therapeutic effect for simple renalcysts.