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Ranieri R, Candeliere F, Sola L, Leonardi A, Rossi M, Amaretti A, Raimondi S. Production of arabitol from glycerol by immobilized cells of Wickerhamomyces anomalus WC 1501. Front Bioeng Biotechnol 2024; 12:1375937. [PMID: 38659644 PMCID: PMC11039890 DOI: 10.3389/fbioe.2024.1375937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 03/26/2024] [Indexed: 04/26/2024] Open
Abstract
Polyalcohols such as arabitol are among the main targets of biorefineries aiming to upcycle wastes and cheap substrates. In previous works Wickerhamomyces anomalus WC 1501 emerged as an excellent arabitol producer utilizing glycerol. Arabitol production by this strain is not growth associated, therefore, in this study, pre-grown cells were entrapped in calcium alginate beads (AB) and utilized for glycerol transformation to arabitol. Flasks experiments aimed to assess the medium composition (i.e., the concentration of inorganic and organic nitrogen sources and phosphates) and to establish the appropriate carrier-to-medium proportion. In flasks, under the best conditions of ammonium limitation and the carrier:medium ratio of 1:3 (w/v), 82.7 g/L glycerol were consumed in 168 h, yielding 31.2 g/L arabitol, with a conversion of 38% and volumetric productivity of 186 mg/mL/h. The process with immobilized cells was transferred to laboratory scale bioreactors with different configurations: stirred tank (STR), packed bed (PBR), fluidized bed (FBR), and airlift (ALR) bioreactors. The STR experienced oxygen limitation due to the need to maintain low stirring to preserve AB integrity and performed worse than flasks. Limitations in diffusion and mass transfer of oxygen and/or nutrients characterized also the PBR and the FBR and were partially relieved only in ALR, where 89.4 g/L glycerol were consumed in 168 h, yielding 38.1 g/L arabitol, with a conversion of 42% and volumetric productivity of 227 mg/mL/h. When the ALR was supplied with successive pulses of concentrated glycerol to replenish the glycerol as it was being consumed, 117 g/L arabitol were generated in 500 h, consuming a total of 285 g/L glycerol, with a 41% and 234 mg/L/h. The study strongly supports the potential of W. anomalus WC 1501 for efficient glycerol-to-arabitol conversion using immobilized cells. While the yeast shows promise by remaining viable and active for extended periods, further optimization is required, especially regarding mixing and oxygenation. Improving the stability of the immobilization process is also crucial for reusing pre-grown cells in multiple cycles, reducing dead times, biomass production costs, and enhancing the economic feasibility of the process.
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Affiliation(s)
- Raffaella Ranieri
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Francesco Candeliere
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Laura Sola
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Alan Leonardi
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Maddalena Rossi
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Biogest-Siteia, University of Modena and Reggio Emilia, Reggio Emilia, Italy
| | - Alberto Amaretti
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Biogest-Siteia, University of Modena and Reggio Emilia, Reggio Emilia, Italy
| | - Stefano Raimondi
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Biogest-Siteia, University of Modena and Reggio Emilia, Reggio Emilia, Italy
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Chen QS, Yuan X, Peng F, Lou WY. Immobilization of engineered E. coli cells for asymmetric reduction of methyl acetoacetate to methyl-(R)-3-hydroxybutyrate. BIORESOUR BIOPROCESS 2022; 9:19. [PMID: 38647599 PMCID: PMC10991218 DOI: 10.1186/s40643-022-00508-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 02/22/2022] [Indexed: 11/10/2022] Open
Abstract
The efficient asymmetric bio-synthesis of chiral β-hydroxy esters is of great importance for industrial production. In this work, a simple and productive engineered E.coli cell-immobilized strategy was applied for the asymmetric reduction of MAA to (R)-HBME with high enantioselectivity. Compared with the corresponding inactivated free cells, the alginate-immobilized cells remained 45% of initial activity at 50 ℃ and 65% after reuse of 10 times. After 60 days of storage at 4 ℃, the immobilized cells maintained more than 80% relative activity. Immobilization contributed significantly to the improvement of thermal stability, pH tolerance, storage stability and operation stability without affecting the yield of product. The immobilized recombinant E. coli cell had absolute enantioselectivity for the asymmetric reduction of MAA to (R)-HBME with e.e. > 99.9%. Therefore, microbial cell immobilization is a perspective approach in asymmetric synthesis of chiral β-hydroxy esters for industrial applications.
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Affiliation(s)
- Qing-Sheng Chen
- Lab of Applied Biocatalysis, School of Food Science and Technology, South China University of Technology, Guangzhou, 510640, Guangdong, China
| | - Xin Yuan
- Lab of Applied Biocatalysis, School of Food Science and Technology, South China University of Technology, Guangzhou, 510640, Guangdong, China
| | - Fei Peng
- Lab of Applied Biocatalysis, School of Food Science and Technology, South China University of Technology, Guangzhou, 510640, Guangdong, China
| | - Wen-Yong Lou
- Lab of Applied Biocatalysis, School of Food Science and Technology, South China University of Technology, Guangzhou, 510640, Guangdong, China.
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The development of alginate-based amperometric nanoreactors for biochemical profiling of living yeast cells. Bioelectrochemistry 2022; 145:108082. [DOI: 10.1016/j.bioelechem.2022.108082] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 01/25/2022] [Accepted: 01/28/2022] [Indexed: 12/27/2022]
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Tian X, Li Y, Chen Y, Mohsin A, Chu J. System optimization of an embedding protocol to immobilize cells from Candida bombicola to improve the efficiency of sophorolipids production. BIORESOURCE TECHNOLOGY 2021; 340:125700. [PMID: 34426247 DOI: 10.1016/j.biortech.2021.125700] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 06/13/2023]
Abstract
This study introduces the implication of immobilization technology in the fermentation process of sophorolipids (SLs) production by Candida bombicola. Firstly, an evaluation system was established for the performance of embedding immobilization and subsequently applied to guide the optimization of operating conditions for sodium alginate immobilization. Correspondingly, the SLs titer increased from 11.4 g/L to 14.6 g/L. Secondly, polyvinyl alcohol was introduced for composite embedding to improve the stability of immobilized beads. Then exogenous addition of 1.5% diatomite further enhanced the fermentation performance of immobilized cells, thereby increasing the SLs titer to 35.9 g/L, which was 2.1 times higher than the original immobilized cells method. Finally, the immobilized cells were tested for three repeated batches of SLs fermentation. Compared to the free cells fermentation, the SLs productivity and substrate conversion rate were increased by 35.5% and 9.1%, respectively. The obtained results showed high potential for application on an industrial scale.
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Affiliation(s)
- Xiwei Tian
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Ya Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Yang Chen
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Ali Mohsin
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Ju Chu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.
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Radosavljević M, Lević S, Belović M, Pejin J, Djukić-Vuković A, Mojović L, Nedović V. Encapsulation of Lactobacillus rhamnosus in Polyvinyl Alcohol for the production of L-(+)-Lactic Acid. Process Biochem 2021. [DOI: 10.1016/j.procbio.2020.10.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Removal of Cadmium from Aqueous Solutions by Saccharomyces cerevisiae-Alginate System. MATERIALS 2019; 12:ma12244128. [PMID: 31835462 PMCID: PMC6947380 DOI: 10.3390/ma12244128] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 12/04/2019] [Accepted: 12/05/2019] [Indexed: 01/16/2023]
Abstract
The aim of this study was to determine the Cd2+ removal capacity of a biosorbent system formed by Saccharomyces cerevisiae in calcium alginate beads. The adsorption of Cd2+ by a S. cerevisiae–alginate system was tested either by batch or fixed-bed column experiments. The S. cerevisiae–alginate system was characterized using dynamic light scattering (DLS, zeta potential), size, hardness, scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy. Beads of the S. cerevisiae–alginate system showed a spherical–elliptical morphology, diameter of 1.62 ± 0.02 mm, 96% moisture, negative surface charge (−29.3 ± 2.57 mV), and texture stability during storage at 4 °C for 20 days. In batch conditions, the system adsorbed 4.3 µg of Cd2+/g of yeast–alginate beads, using a Cd2+ initial concentration of 5 mg/L. Adsorption capacity increased to 15.4 µg/g in a fixed-bed column system, removing 83% of total Cd2+. In conclusion, the yeast–alginate system is an efficient option for the removal of cadmium at low concentrations in drinking water.
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Radosavljević M, Lević S, Belović M, Pejin J, Djukić-Vuković A, Mojović L, Nedović V. Immobilization of Lactobacillus rhamnosus in polyvinyl alcohol/calcium alginate matrix for production of lactic acid. Bioprocess Biosyst Eng 2019; 43:315-322. [PMID: 31605205 DOI: 10.1007/s00449-019-02228-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 09/06/2019] [Accepted: 09/29/2019] [Indexed: 12/11/2022]
Abstract
Immobilization of Lactobacillus rhamnosus ATCC7469 in poly(vinyl alcohol)/calcium alginate (PVA/Ca-alginate) matrix using "freezing-thawing" technique for application in lactic acid (LA) fermentation was studied in this paper. PVA/Ca-alginate beads were made from sterile and non-sterile PVA and sodium alginate solutions. According to mechanical properties, the PVA/Ca-alginate beads expressed a strong elastic character. Obtained PVA/Ca-alginate beads were further applied in batch and repeated batch LA fermentations. Regarding cell viability, L. rhamnosus cells survived well rather sharp immobilization procedure and significant cell proliferation was observed in further fermentation studies achieving high cell viability (up to 10.7 log CFU g-1) in sterile beads. In batch LA fermentation, the immobilized biocatalyst was superior to free cell fermentation system (by 37.1%), while the highest LA yield and volumetric productivity of 97.6% and 0.8 g L-1 h-1, respectively, were attained in repeated batch fermentation. During seven consecutive batch fermentations, the biocatalyst showed high mechanical and operational stability reaching an overall productivity of 0.78 g L-1 h-1. This study suggested that the "freezing-thawing" technique can be successfully used for immobilization of L. rhamnosus in PVA/Ca-alginate matrix without loss of either viability or LA fermentation capability.
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Affiliation(s)
- Miloš Radosavljević
- University of Novi Sad, Faculty of Technology Novi Sad, Bul. Cara Lazara 1, 21 000, Novi Sad, Serbia.
| | - Steva Lević
- University of Belgrade, Faculty of Agriculture, Nemanjina 6, 11 080, Belgrade, Serbia
| | - Miona Belović
- Institute of Food Technology in Novi Sad, University of Novi Sad, Bul. Cara Lazara 1, 21000, Novi Sad, Serbia
| | - Jelena Pejin
- University of Novi Sad, Faculty of Technology Novi Sad, Bul. Cara Lazara 1, 21 000, Novi Sad, Serbia
| | - Aleksandra Djukić-Vuković
- University of Belgrade, Faculty of Technology and Metallurgy, Karnegijeva 4, 11 000, Belgrade, Serbia
| | - Ljiljana Mojović
- University of Belgrade, Faculty of Technology and Metallurgy, Karnegijeva 4, 11 000, Belgrade, Serbia
| | - Viktor Nedović
- University of Belgrade, Faculty of Agriculture, Nemanjina 6, 11 080, Belgrade, Serbia
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Abstract
Jamming state transition has been used in literature to describe migrating-to-resting cell state transition during collective cell migration without proper rheological confirmation. Yield stress often has been used as an indicator of a jamming state. Yield stress points to the liquid-to-solid state transition, but not a priori to jamming state transition. Various solid states such as elastic solid and viscoelastic solids can be considered in the context of their ability to relax. The relaxation time for (1) an elastic solid tends to zero, (2) Kelvin-Voigt viscoelastic solid is finite, and (3) jamming state tends to infinity. In order to clarify the meaning of jamming state from the rheological standpoint we formulated the constitutive model of this state based on following conditions (1) migration of the system constituents is much damped such that the diffusion coefficient tends to zero, (2) relaxation time tends to infinity, (3) storage and loss moduli satisfy the condition G′(ω)/G"(ω) = const > 1. Jamming state represents the non-linear viscoelastic solid state. The main characteristic of this state is that the system cannot relax. Jamming state transition of multicellular systems caused by collective cell migration is discussed on a model system such as cell aggregate rounding after uni-axial compression between parallel plates based on the data from the literature. Cell aggregate rounding occurs via successive relaxation cycles. Every cycle corresponds to a different scenario of cell migration. Three scenarios were established depending on the magnitude of mechanical and biochemical perturbations (1) ordered scenario with reduced perturbations corresponds to the case that most of the cells migrate, (2) disordered scenario corresponds to the case that some cell groups migrate while the others (at the same time) stay in resting state (corresponds to medium perturbations), and (3) highly suppressed cell migration under large perturbations corresponds to the viscoelastic solid under jamming state. If cells reach the jamming state in one cycle, they are able to overcome this undesirable state and start migrating again in the next cycle by achieving the first or second scenarios again.
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Effect of Encapsulated Probiotic Starter Culture on Rheological and Structural Properties of Natural Hydrogel Carriers Affected by Fermentation and Gastrointestinal Conditions. FOOD BIOPHYS 2019. [DOI: 10.1007/s11483-019-09598-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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da Silva Serres JD, Taisline Bandeira P, Cabral Zappani P, Piovan L, Corazza ML. A greener bioreduction using baker’s yeast cells in supercritical carbon dioxide and glycerol system. J Supercrit Fluids 2019. [DOI: 10.1016/j.supflu.2018.09.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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11
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Zhu C, Yang WL, He H, Yang C, Yu J, Wu X, Zeng G, Tarre S, Green M. Preparation, performances and mechanisms of magnetic Saccharomyces cerevisiae bionanocomposites for atrazine removal. CHEMOSPHERE 2018; 200:380-387. [PMID: 29499518 DOI: 10.1016/j.chemosphere.2018.02.020] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Revised: 11/11/2017] [Accepted: 02/04/2018] [Indexed: 06/08/2023]
Abstract
Saccharomyces cerevisiae and nanoparticles of iron oxide (Fe3O4) which were linked with chitosan (CS) through epichlorohydrin (ECH) were encapsulated in calcium alginate to prepare a novel type of bionanocomposites. Characterization results showed that the Fe3O4-ECH-CS nanoparticles were quasi-spherical with an average diameter of 30 nm to which chitosan was successfully attached through epichlorohydrin. The saturation magnetization value of the nanoparticles was 21.88 emu/g, and ferrous and ferric irons were simultaneously observed in the magnetic nanoparticles. Data of atrazine removal by yeasts showed that both inactivated and live yeasts could decrease the concentration of atrazine effectively. The inactivated yeasts achieved 20% removal rate, which indicated that adsorption by the yeasts also played a role in the removal. Removal efficiency of atrazine was maximized at 88% under 25 °C, pH of 7 and an initial atrazine concentration of 2 mg/L. When the magnetic bionanocomposite was recycled and reused twice, only 12% and 20% drop in removal efficiency was observed at the first time and the second time severally. So, atrazine could be used by the yeasts as the sole carbon source for growth and multiplication, and both adsorption and biodegradation by the bionanocomposite contributed to atrazine removal.
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Affiliation(s)
- Canyao Zhu
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - William L Yang
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Huijun He
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China.
| | - Chunping Yang
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China; Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, College of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, Zhejiang, 310018, China.
| | - Jiaping Yu
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Xin Wu
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Sheldon Tarre
- Faculty of Civil and Environmental Engineering, Technion, Haifa, 32000, Israel
| | - Michal Green
- Faculty of Civil and Environmental Engineering, Technion, Haifa, 32000, Israel
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Zhao W, Zhou T, Zhu J, Sun X, Xu Y. Adsorption of cadmium ions using the bioadsorbent of Pichia kudriavzevii YB5 immobilized by polyurethane foam and alginate gels. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:3745-3755. [PMID: 29168136 DOI: 10.1007/s11356-017-0785-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 11/16/2017] [Indexed: 06/07/2023]
Abstract
Pichia kudriavzevii YB5, mutated from Pichia kudriavzevii A16 with a strong ability to remove cadmium ions, was immobilized by polyurethane foam and alginate gels in this work. The immobilization conditions were optimized as follows: sodium alginate concentration of 2% (w/v), calcium chloride concentration of 2% (w/v), biomass dose of 1 × 109 cell/mL, and cross-linking time for 4 h. Then, the results of batch adsorption experiments showed that the removal capacity of prepared bioadsorbent was significantly affected by the pH of media, contact time, and the initial Cd(II) concentration, and a suitable adsorption conditions of Cd(II) could be achieved with a pH value of 6.0 at 20 °C for 90 min. Kinetic and isothermal results indicated the behavior of Cd(II) adsorption onto immobilized P. kudriavzevii YB5 fitted to the pseudo-second-order kinetic equation and the Langmuir adsorption model. Thermodynamic results showed that the Cd(II) adsorption process was endothermic and spontaneous in nature. Besides, the Cd(II) removing capacity of the prepared bioadsorbent was also tested in the oyster hydrolysates, showing an average removal rate of 54.35%. Thus, the immobilized P. kudriavzevii YB5 adsorbent had great potential for application in aquatic products to ensure the food safety.
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Affiliation(s)
- Wenyu Zhao
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, People's Republic of China
| | - Ting Zhou
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, People's Republic of China
| | - Junxiang Zhu
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, People's Republic of China
- Marine Fisheries Research Institute of Zhejiang, Zhoushan, 316021, People's Republic of China
| | - Xun Sun
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, People's Republic of China
| | - Ying Xu
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, People's Republic of China.
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Pajic-Lijakovic I, Milivojevic M. Modeling of the metabolic energy dissipation for restricted tumor growth. J Bioenerg Biomembr 2017; 49:381-389. [PMID: 28852947 DOI: 10.1007/s10863-017-9723-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 08/11/2017] [Indexed: 11/30/2022]
Abstract
Energy dissipation mostly represents unwanted outcome but in the biochemical processes it may alter the biochemical pathways. However, it is rarely considered in the literature although energy dissipation and its alteration due to the changes in cell microenvironment may improve methods for guiding chemical and biochemical processes in the desired directions. Deeper insight into the changes of metabolic activity of tumor cells exposed to osmotic stress or irradiation may offer the possibility of tumor growth reduction. In this work effects of the osmotic stress and irradiation on the thermodynamical affinity of tumor cells and their damping effects on metabolic energy dissipation were investigated and modeled. Although many various models were applied to consider the tumor restrictive growth they have not considered the metabolic energy dissipation. In this work a pseudo rheological model in the form of "the metabolic spring-pot element" is formulated to describe theoretically the metabolic susceptibility of tumor spheroid. This analog model relates the thermodynamical affinity of cell growth with the volume expansion of tumor spheroid under isotropic loading conditions. Spheroid relaxation induces anomalous nature of the metabolic energy dissipation which causes the damping effects on cell growth. The proposed model can be used for determining the metabolic energy "structure" in the context of restrictive cell growth as well as for predicting optimal doses for cancer curing in order to tailor the clinical treatment for each person and each type of cancer.
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Affiliation(s)
- Ivana Pajic-Lijakovic
- Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, Belgrade, 11120, Serbia
| | - Milan Milivojevic
- Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, Belgrade, 11120, Serbia.
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Celik Kazici H, Bayraktar E, Mehmetoglu Ü. Production of precursors for anti-Alzheimer drugs: Asymmetric bioreduction in a packed-bed bioreactor using immobilized D. carota cells. Prep Biochem Biotechnol 2017; 47:67-73. [PMID: 27092587 DOI: 10.1080/10826068.2016.1168840] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
(S)-1-Phenylethanol derivatives, which are the precursors of many pharmacological products, have also been used as anti-Alzheimer drugs. Bioreduction experiments were performed in a batch and packed-bed bioreactor. Then, the kinetics constants were determined by examining the reaction kinetics in the batch system with free and immobilized carrot cells. Also, the effective diffusion coefficient (De) of acetophenone in calcium alginate-immobilized carrot cells was investigated. Kinetics constants for free cells, which are intrinsic values, are reaction rate Vmax = 0.052 mmol L-1 min-1, and constants of the Michaelis-Menten KM = 2.31 mmol L-1. Kinetics constants for immobilized cells, which are considered apparent values, are Vmax, app = 0.0407 mmol L-1 min-1, KM, app = 3.0472 mmol L-1 for 2 mm bead diameter, and Vmax, app = 0.0453 mmol L-1 min-1, KM, app = 4.9383 mmol L-1 for 3 mm bead diameter. Average value of effective diffusion coefficient of acetophenone in immobilized beads was determined as 1.97 × 10-6 cm2 s-1. Using immobilized carrot cells in an up-flow packed-bed reactor, continuous production of (S)-1-phenylethanol through asymmetric bioreduction of acetophenone was performed. The effects of the residence time and concentrations of substrate were investigated at pH 7.6 and 33°C. Enantiomerically pure (S)-1-phenylethanol (ee > 99%) was produced with 75% conversion at 4-hr residence time.
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Affiliation(s)
- Hilal Celik Kazici
- a Department of Chemical Engineering, Faculty of Engineering , Yuzuncu Yil University , Van , Turkey
| | - Emine Bayraktar
- b Department of Chemical Engineering, Faculty of Engineering , Ankara University , Ankara , Turkey
| | - Ülkü Mehmetoglu
- b Department of Chemical Engineering, Faculty of Engineering , Ankara University , Ankara , Turkey
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Pajic-Lijakovic I, Milivojevic M, Levic S, Trifkovic K, Stevanovic-Dajic Z, Radosevic R, Nedovic V, Bugarski B. Matrix resistance stress: A key parameter for immobilized cell growth regulation. Process Biochem 2017. [DOI: 10.1016/j.procbio.2016.10.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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16
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Development of zirconia nanoparticles-decorated calcium alginate hydrogel fibers for extraction of organophosphorous pesticides from water and juice samples: Facile synthesis and application with elimination of matrix effects. J Chromatogr A 2016; 1473:28-37. [DOI: 10.1016/j.chroma.2016.10.071] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 10/16/2016] [Accepted: 10/26/2016] [Indexed: 12/12/2022]
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17
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Alginate Biosynthesis inAzotobacter vinelandii: Overview of Molecular Mechanisms in Connection with the Oxygen Availability. INT J POLYM SCI 2016. [DOI: 10.1155/2016/2062360] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Gram-negative bacteriumAzotobacter vinelandiican synthetize the biopolymer alginate that has material properties appropriate for plenty of applications in industry as well as in medicine. In order to settle the foundation for improving alginate production without compromising its quality, a better understanding of the polymer biosynthesis and the mechanism of regulation during fermentation processes is necessary. This knowledge is crucial for the development of novel production strategies. Here, we highlight the key aspects of alginate biosynthesis that can lead to producing an alginate with specific material properties with particular focus on the role of oxygen availability linked with the molecular mechanisms involved in the alginate production.
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