Vitamin B12 and Marine Ecology. IV. The Kinetics of Uptake, Growth and Inhibition in Monochrysis Lutheri

1968 ◽  
Vol 48 (3) ◽  
pp. 689-733 ◽  
Author(s):  
M. R. Droop
Keyword(s):  
Growth Rate ◽  
Substrate Concentration ◽  
Specific Growth ◽  
Marine Ecology ◽  
Vitamin B ◽  
Batch Cultures ◽  
Washed Cell ◽  
Cell Quota ◽  
Kinetics Of Uptake ◽  
Kinetics Of

57Co-labelled vitamin B12 was used to study the kinetics of vitamin B12 limitation in Monochrysis lutheri in continuous and exponentially growing batch cultures and in washed cell suspensions.Specific growth rate in the chemostats was found not to depend directly on medium substrate concentration but on the concentration within the cells (cell quota), obeying a hyperbolic equation of the form

scholarly journals AKTIVITAS INULINASE OLEH Pichia manshurica DAN FUSAN F4 PADA FERMENTASI BATCH DENGAN UMBI DAHLIA (Dahlia sp) SEBAGAI SUBSTRAT

REAKTOR ◽  
2015 ◽  
Vol 14 (3) ◽  
pp. 187 ◽  
Author(s):  
Wijanarka Wijanarka ◽  
Endang Sutariningsih Soetarto ◽  
Kumala Dewi ◽  
Ari Indrianto
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Specific Growth ◽  
Lag Phase ◽  
Growth Media ◽  
A Value ◽  
Inulinase Activity ◽  
Pichia Manshurica ◽  
Microbial Strains ◽  
Kinetics Of

ACTIVITY OF INULINASE OF Pichia Manshuria AND FUSAN F4 ON BATCH FERMENTATION UDING DAHLIA TUBER (Dahlia sp) AS A SUBSTRATE. A dahlia tuber is one of the common inulin rich crops. Inulin is formed by units of fructans, which are polymers of D-fructose. Inulinases (EC 3.2.1.7) catalyze the hydrolysis of inulin, producing fructooligosaccharides (FOS), inulooligosaccharides (IOS), pulullan, acetone, butanol and sorbitol, therefore dahlia tubers are used as growth media. The inulin hydrolyzing activity has been reported from various microbial strains Pichia manshurica and Fusan F4 which is the result of fusion protoplast. The objective of this study was to determine the activity of inulinase Pichia manshurica and Fusan F4 on the substrate dahlia tubers. Fusan F4 to increase inulinase activity compared with Pichia manshurica and to investigate the kinetics of specific growth rate (μ) and time double (g) from of Pichia manshurica and Fusan F4. The results showed that the exponential phase occurs at 0-12 hour without a lag phase. P. manshurica has a specific growth rate (μ) of 0.18/hour with time double (g) 3.90 hours and the inulinase enzyme activity of 0.56 IU, while for Fusan F4 consecutive has a value μ of 0.20/hour, g of 3.49 hours and the activity of 0.69 IU. The conclusion of this research is to improve Fusan F4 inulinase activity and the ability has to be better than the Pichia manshurica.Umbi dahlia merupakan salah satu umbi yang mengandung inulin. Inulin merupakan polimer fruktan yang dapat dipecah oleh enzim inulinase (E.C. 3.2.1.7) menjadi fruktosa. Fruktosa merupakan bahan baku dasar untuk pembuatan FOS, IOS, pulullan, aseton dan sorbitol, oleh karena itu umbi dahlia digunakan sebagai media pertumbuhan. Enzim inulinase ini secara indigenous dimiliki oleh Pichia manshurica dan Fusan F4 yang merupakan hasil fusi protoplas.Tujuan  penelitian ini adalah  untuk mengetahui aktivitas inulinase Pichia manshurica dan Fusan F4 pada substrat umbi dahlia, Fusan F4 mampu meningkatkan aktivitas inulinase dibandingkan dengan Pichia manshurica serta untuk mengetahui kinetika kecepatan pertumbuhan specifik (µ) dan waktu generasi (g) Pichia manshurica dan Fusan F4. Hasil penelitian menunjukkan bahwa fase  eksponensial terjadi pada jam ke-0 sampai jam ke-12 tanpa diikuti fase lag, Pichia manshurica mempunyai kecepatan pertumbuhan specific (µ)  sebesar 0,18/jam dengan waktu generasi (g) 3,90 jam dan aktivitas enzim inulinase yang dihasilkan sebesar 0,56 IU, sedangkan untuk fusan F4 secara berturut-turut mempunyai nilai µ sebesar 0,20/jam, g sebesar 3,49 jam dan aktivitas sebesar 0,69 IU. Kesimpulan dari penelitian ini adalah Fusan F4 mampu meningkatkan aktivitas inulinase dan mempunyai kemampuan lebih baik dibanding dengan Pichia manshurica.

Influence of specific growth rate over the secretory expression of recombinant potato carboxypeptidase inhibitor in fed-batch cultures of Escherichia coli

2010 ◽  
Vol 45 (8) ◽  
pp. 1334-1341 ◽  
Author(s):  
Juan-Miguel Puertas ◽  
Jordi Ruiz ◽  
Mónica Rodríguez de la Vega ◽  
Julia Lorenzo ◽  
Glòria Caminal ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Growth Rate ◽  
Specific Growth Rate ◽  
Specific Growth ◽  
Fed Batch ◽  
Secretory Expression ◽  
Batch Cultures ◽  
Carboxypeptidase Inhibitor

The kinetics of growth control in a colonial hydroid

1981 ◽  
Vol 61 (1) ◽  
pp. 35-63 ◽  
Author(s):  
A. R. D. Stebbing
Keyword(s):  
Growth Rate ◽  
Growth Process ◽  
Control Mechanism ◽  
Specific Growth ◽  
Growth Control ◽  
Temporal Variations ◽  
Controlled Experiments ◽  
Rates Of Growth ◽  
Kinetics Of ◽  
Colonial Hydroid

It is suggested that the cumulative view of growth in which some index of biomass is plotted against time tends to obscure temporal variations in the growth process that might provide evidence of how it is controlled. Experiments with the colonial hydroid Campanularia flexuosa show that the action of a growth control mechanism can be demonstrated by considering changes in specific rates of growth determined at frequent intervals in time. However, it is also necessary to disturb the growth process slightly in order to initiate the action of the control mechanism, and having done so, to isolate the effect of the disturbance on growth and thus the action of the control mechanism. This is done by expressing the specific growth rate of organisms whose growth is disturbed as a percentage of that of control organisms of the same age.

scholarly journals Modeling and Use of Inter-Criteria Decision Analysis for Selecting Growth Rate Models for Batch Cultivation of Yeast Kluyveromyces marxianus var. lactis MC 5

Fermentation ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 163
Author(s):  
Mitko Petrov
Keyword(s):  
Growth Rate ◽  
Decision Analysis ◽  
Specific Growth ◽  
Batch Cultivation ◽  
Process Models ◽  
Monod Model ◽  
First Time ◽  
Kinetics Of ◽  
Additive Form ◽  
Selection Of

Ten unstructured models of Monod, Mink, Tessier, Moser, Aiba, Andrews, Haldane, Luong, Edward, and Han-Levenspiel are considered in this paper to explain the kinetics of cell growth for batch cultivation of the yeast Kluyweromyces marxianus var. lactis MC 5. For the first time, two independent kinetic models are used to model the process for the two basic substrates—lactose and oxygen. The selection of the most appropriate growth rate models has been made through a new multi-criteria decision-making approach called the Inter-Criteria Decision Analysis (ICDA) method. The application of ICDA to the growth rate of lactose and oxygen alone has shown that there have been many correlations between the studied models. Thus, the models for the growth rate, depending only on lactose, are reduced to one—Monod model and there are two models—Monod and Mink—depending on oxygen only. Separate kinetic process models have been developed for the combination of Monod–Monod and Monod–Mink models. For the first time, in addition to the multiplicative form, the additive form of a specific growth rate has been studied. The comparison of the obtained results has shown that the additive form has shown better results than the multiplicative one. For this reason, the additive form of the Monod–Monod model will be used to model the process.

scholarly journals Specific growth rate governs AOX1 gene expression, affecting the production kinetics of Pichia pastoris (Komagataella phaffii) PAOX1-driven recombinant producer strains with different target gene dosage

2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Javier Garrigós-Martínez ◽  
Miguel Angel Nieto-Taype ◽  
Arnau Gasset-Franch ◽  
José Luis Montesinos-Seguí ◽  
Xavier Garcia-Ortega ◽  
...  
Keyword(s):  
Gene Expression ◽  
Growth Rate ◽  
Pichia Pastoris ◽  
Specific Growth Rate ◽  
Specific Growth ◽  
Gene Dosage ◽  
Fed Batch ◽  
Komagataella Phaffii ◽  
Production Kinetics ◽  
Kinetics Of

Abstract Background The PAOX1-based expression system is the most widely used for producing recombinant proteins in the methylotrophic yeast Pichia pastoris (Komagataella phaffii). Despite relevant recent advances in regulation of the methanol utilization (MUT) pathway have been made, the role of specific growth rate (µ) in AOX1 regulation remains unknown, and therefore, its impact on protein production kinetics is still unclear. Results The influence of heterologous gene dosage, and both, operational mode and strategy, on culture physiological state was studied by cultivating the two PAOX1-driven Candida rugosa lipase 1 (Crl1) producer clones. Specifically, a clone integrating a single expression cassette of CRL1 was compared with one containing three cassettes over broad dilution rate and µ ranges in both chemostat and fed-batch cultivations. Chemostat cultivations allowed to establish the impact of µ on the MUT-related MIT1 pool which leads to a bell-shaped relationship between µ and PAOX1-driven gene expression, influencing directly Crl1 production kinetics. Also, chemostat and fed-batch cultivations exposed the favorable effects of increasing the CRL1 gene dosage (up to 2.4 fold in qp) on Crl1 production with no significant detrimental effects on physiological capabilities. Conclusions PAOX1-driven gene expression and Crl1 production kinetics in P. pastoris were successfully correlated with µ. In fact, µ governs MUT-related MIT1 amount that triggers PAOX1-driven gene expression—heterologous genes included—, thus directly influencing the production kinetics of recombinant protein.

Effect of carbon dioxide on growth of Pseudomonas putida ATCC 11172 on asparagine, citrate, glucose, and lactate in batch and continuous culture

1985 ◽  
Vol 31 (9) ◽  
pp. 763-766 ◽  
Author(s):  
Göran Molin
Keyword(s):  
Carbon Dioxide ◽  
Growth Rate ◽  
Pseudomonas Putida ◽  
Continuous Culture ◽  
Specific Growth ◽  
Carbon Sources ◽  
Maximum Specific Growth Rate ◽  
The Other ◽  
Continuous Cultures ◽  
Batch Cultures

The growth of Pseudomonas putida ATCC 11172 on L-asparagine, citrate, D-glucose, and L-lactate was followed in air and in 40% CO2 + air, using batch and carbon-limited continuous cultures. Batch cultures in air utilized a mixture of the carbon sources simultaneously. However, a change to 40% CO2 favoured the utilization of glucose. The maximum specific growth rate (μmax) in air was about 0.3 h−1 on glucose and 0.6 h−1 on the other carbon sources. In CO2, the μmax for glucose was reduced by 16% compared with almost 60–70% for the others. An order of preference for the different carbon sources in continuous cultures was determined by comparing the dilution rates at which the different carbon sources started to appear in the effluent. Glucose was the first compound to appear as the dilution rate increased (lowest preference when grown in air). In 40% CO2, the μmax for glucose was slightly higher than the others and the recorded preference for glucose in continuous culture was equal to that for citrate but was somewhat lower than that of lactate and asparagine. D-Gluconate and glucono-δ-lactone were produced as a step in the utilization of glucose. The D-gluconate production was enhanced by CO2.

scholarly journals Kinetika detoksifikasi umbi gadung (dioscorea hispida dennst.) secara fermentasi dengan kapang mucor racemosus

REAKTOR ◽  
2017 ◽  
Vol 17 (2) ◽  
pp. 81 ◽  
Author(s):  
Marissa Widiyanti ◽  
Andri Cahyo Kumoro
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Specific Growth ◽  
Cyanogenic Glucosides ◽  
Mucor Racemosus ◽  
Dry Land ◽  
Physical Chemical ◽  
Fungal Fermentation ◽  
Biological Methods ◽  
Kinetics Of

Abstract THE KINETICS OF GADUNG (Dioscorea hispida dennst.) TUBER DETOXIFICATION VIA FUNGAL FERMENTATION USING Mucor racemosus. Bitter yam (Dioscorea hispida Dennst.) is one of carbohydrate sources used as staple food commonly found in Indonesian dry-land. However, this tuber has been underutilized due to the presence of an antinutrition compound, namely cyanogenic glucosides. Removal of cyanides from foodstuffs can be done either by physical, chemical or biological methods. In this study, the effect of time on the detoxification of gadung tuber chips from cyanides via fermentation using Mucor racemosus and its kinetics were investigated. Gadung chip samples were withdrawn from the fermentation system at every 24 hours interval for biomass and cyanides contents analysis. It was clear that the cyanides content decreased as the fermentation went by. Safely consumed gadung tuber chips were obtained from fermentation of the chips for 120 hours from which cyanides content as low as 49.41 mg/kg was achieved. The logistic equation successfully described the growth rate of Mucor racemosus under studied condition. The specific growth rate of Mucor racemosus in gadung chips was found to be 0.0297/hr or about a half of specific growth rate of that mold when grown in the readily consumed yeast-pepton-glucose (YPG) media. Keywords: fermentation; yam; monod; Mucor racemosus; cyanogen  Abstrak Umbi gadung (Dioscorea hispida Dennst.) merupakan salah satu sumber karbohidrat yang digunakan sebagai makanan pokok yang biasa ditemukan di lahan kering di wilayah Indonesia. Namun, umbi ini kurang dimanfaatkan karena adanya senyawa antinutrisi, yaitu cyanogenic glucosides. Penghilangan senyawa sianida dari bahan makanan dapat dilakukan baik dengan metode fisik, kimia atau biologi. Penelitian ini bertujuan untuk mengkaji pengaruh waktu pada detoksifikasi irisan umbi gadung dari senyawa sianida melalui fermentasi dengan menggunakan kapang Mucor racemosus dan kinetikanya. Cuplikan irisan umbi gadung diambil dari sistem fermentasi pada setiap jeda waktu 24 jam untuk dianalisis kadar biomassa dan sianidanya. Hasil penelitian menunjukkan bahwa kandungan sianida menurun seiring dengan bertambahnya waktu fermentasi. Irisan umbi gadung yang aman dikonsumsi dapat diperoleh dari fermentasi irisan ubi gadung selama 120 jam dengan kandungan sianida serendah 49,41 mg/kg. Persamaan logistik berhasil menggambarkan tingkat pertumbuhan kapang Mucor racemosus dengan baik. Tingkat pertumbuhan spesifik dari Mucor racemosus pada irisan umbi gadung adalah 0,0297/jam atau sekitar setengah dari laju pertumbuhan spesifik jamur tersebut saat dibudidayakan pada media yang siap dikonsumsi, seperti ragi-pepton-glukosa (YPG). Kata kunci: fermentasi; gadung; monod; Mucor racemosus; sianogen 

Estimation and control of non-linear variables in a continuous fermentation process using sliding mode techniques

2011 ◽  
Vol 34 (7) ◽  
pp. 769-779 ◽  
Author(s):  
AFNA Rahman ◽  
SK Spurgeon ◽  
XG Yan
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Substrate Concentration ◽  
Fermentation Process ◽  
Consumption Rate ◽  
Specific Growth ◽  
Sliding Mode ◽  
Biomass Concentration ◽  
Substrate Consumption ◽  
Non Linear

Biomass, substrate or metabolite concentrations are difficult to measure online in fermentation processes because of the lack of reliable, cheap and sterilizable transducers. Currently, many of the measurements required may be determined through offline analysis, which is costly and time consuming. Furthermore, the specific growth rate conditions involved in the fermentation are typically non-linear and uncertain. In this paper, a new variable, the substrate consumption rate, consisting of a combination of substrate concentration, biomass concentration, specific growth rate and yield production coefficient, is introduced to overcome these problems and simplify the non-linear differential equations of the fermentation process. A sliding mode observer, which only requires measurement of substrate concentration, is then developed to solve the estimation problem, providing a soft sensor to estimate the substrate consumption rate. It is shown that the sliding mode exhibited by the corresponding observer error dynamics is exponentially stable. This parameterization and the resulting estimate of biomass concentration are then utilized within a feedback control strategy. Non-linear simulation results in the presence of both parameter uncertainties and external disturbances illustrate the approach.

Siderophore production by Fusarium venenatum A3/5

2002 ◽  
Vol 30 (4) ◽  
pp. 696-698 ◽  
Author(s):  
M. G. Wiebe
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Environmental Conditions ◽  
Continuous Flow ◽  
Specific Growth ◽  
Chemostat Culture ◽  
Siderophore Production ◽  
Batch Cultures ◽  
Chemostat Cultures ◽  
Fusarium Venenatum

Fusarium venenatum A3/5 was grown in iron-restricted batch cultures and iron-limited chemostat cultures to determine how environmental conditions affected siderophore production. The specific growth rate in iron-restricted batch cultures was 0.22 h−1, which was reduced to 0.12 h−1 when no iron was added to the culture. Derit in iron-limited chemostat culture was 0.1 h−1. Siderophore production was correlated with specific growth rate, with the highest siderophore production occurring at D = 0.08 h−1 and the lowest at D = 0.03 h−1. Siderophore production was greatest at pH 4.7 and was significantly reduced at pHs above 6.0. Siderophore production could be enhanced by providing insoluble iron instead of soluble iron in continuous flow cultures.

scholarly journals Cellular Microcystin Content in N-Limited Microcystis aeruginosa Can Be Predicted from Growth Rate

2001 ◽  
Vol 67 (1) ◽  
pp. 278-283 ◽  
Author(s):  
Benedict M. Long ◽  
Gary J. Jones ◽  
Philip T. Orr
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Cell Volume ◽  
Microcystis Aeruginosa ◽  
Specific Growth ◽  
Weight Ratio ◽  
Dry Weight ◽  
Cell Protein ◽  
Protein Ratio ◽  
Cell Quota

ABSTRACT Cell quotas of microcystin (Q MCYST; femtomoles of MCYST per cell), protein, and chlorophyll a(Chl a), cell dry weight, and cell volume were measured over a range of growth rates in N-limited chemostat cultures of the toxic cyanobacterium Microcystis aeruginosa MASH 01-A19. There was a positive linear relationship betweenQ MCYST and specific growth rate (μ), from which we propose a generalized model that enablesQ MCYST at any nutrient-limited growth rate to be predicted based on a single batch culture experiment. The model predicts Q MCYST from μ, μmax(maximum specific growth rate), Q MCYSTmax(maximum cell quota), and Q MCYSTmin (minimum cell quota). Under the conditions examined in this study, we predict aQ MCYSTmax of 0.129 fmol cell−1 at μmax and a Q MCYSTmin of 0.050 fmol cell−1 at μ = 0. Net MCYST production rate (R MCYST) asymptotes to zero at μ = 0 and reaches a maximum of 0.155 fmol cell−1 day−1at μmax. MCYST/dry weight ratio (milligrams per gram [dry weight]) increased linearly with μ, whereas the MCYST/protein ratio reached a maximum at intermediate μ. In contrast, the MCYST/Chla ratio remained constant. Cell volume correlated negatively with μ, leading to an increase in intracellular MCYST concentration at high μ. Taken together, our results show that fast-growing cells of N-limited M. aeruginosa are smaller, are of lower mass, and have a higher intracellular MCYST quota and concentration than slow-growing cells. The data also highlight the importance of determining cell MCYST quotas, as potentially confusing interpretations can arise from determining MCYST content as a ratio to other cell components.

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