Fedbatch Culture and Dynamic Nutrient Feeding

2006 ◽  
pp. 43-74 ◽  
Author(s):  
Katie F. Wlaschin ◽  
Wei-Shou Hu
Keyword(s):  
Nutrient Feeding

scholarly journals Optimizing the nutrient feeding strategy for PHA production by a novel strain of Enterobacter sp.

2015 ◽  
Vol 12 (8) ◽  
pp. 2757-2764 ◽  
Author(s):  
V. Vinish ◽  
S. H. Sangeetha ◽  
J. Aravind ◽  
P. Kanmani ◽  
T. Sathiskumar
Keyword(s):  
Feeding Strategy ◽  
Pha Production ◽  
Nutrient Feeding

Phosphorus kinetics of cattle grazing tropical pastures and implications for the estimation of their phosphorus requirements

1992 ◽  
Vol 119 (3) ◽  
pp. 401-409 ◽  
Author(s):  
D. B. Coates ◽  
J. H. Ternouth
Keyword(s):  
Drinking Water Treatment ◽  
The Other ◽  
Tropical Pastures ◽  
Faecal Excretion ◽  
Soil P ◽  
North East ◽  
The Difference ◽  
Nutrient Feeding ◽  
Kinetics Of ◽  
P Absorption

SUMMARYTwelve yearling Droughtmaster heifers were grazed on a tropical grass/legume pasture in north-east Australia for 1 year in four paddocks, each of 4 ha. One paddock was fertilized annually with 10 kg P/ha (treatment HPF). The other three paddocks had low soil P and low pasture P status. In one of the low soil P paddocks, P was added to the drinking water (treatment HPS) but no supplement was provided in the other two paddocks (treatments LP1 and LP2). In February, May and August 1989, the P kinetics of the heifers were monitored following oral administration of ruminal chromic oxide capsules and i/v injection of 32P. At the same times, oesophageal-fistulated steers were grazed in the paddocks to obtain extrusa samples to estimate the P content and digestibility of selected forage.The liveweight gain per heifer was higher in the HP treatments (196 kg) than in the LP treatments (152 kg). The intake, absorption and excretion of P were closely related but the faecal excretion of P relative to P intake was less in heifers with than without P supplement. The P intakes of the LP heifers were about half the quantities recommended in the nutrient feeding standards for the observed food intakes and weight gains. The coefficients of P absorption in the LP heifers in May and August were high (> 0·8) and did not decrease with age or liveweight. The coefficients of P absorption of heifers given supplementary P were as high as those for LP heifers, but those of heifers on the fertilized pasture were significantly lower in May and August. The endogenous faecal excretion of P was related to P intake but more closely to dry matter intake and plasma inorganic P together. The reasons for the difference between observed P intakes of LP heifers and recommended requirements are discussed in relation to the assessment of P requirements of grazing cattle. The results from this experiment suggest that recommended P requirements are higher than necessary to sustain the measured liveweight gains of cattle on grass/legume pastures in the tropics.

scholarly journals EFFECTS OF NUTRIENT CONCENTRATION IN MULTI STAGE FEEDING OF THE GROWTH OF MICROALGAE Nannochloropsis sp.

2018 ◽  
Vol 40 (2) ◽  
pp. 76
Author(s):  
Lies Sriwuryandari ◽  
Ekaputra Agung Priantoro ◽  
Tarzan Sembiring
Keyword(s):  
Fatty Acid ◽  
Lipid Level ◽  
Lipid Synthesis ◽  
Dihydrogen Phosphate ◽  
Molecular Formula ◽  
Sodium Dihydrogen Phosphate ◽  
Cell Biomass ◽  
Multi Stage ◽  
Four Levels ◽  
Nutrient Feeding

Renewable energy plays an important role for a sustainable future and the use of microalgae Nannochloropsis sp., as a potential source of biofuel due to its high lipid content, makes a good option. The nutrient found in the growth medium of microalgae have been found to affect cell synthesis, lipid synthesis, as well as its fatty acid profile. This study was conducted to observe the effects of the N-P concentration utilizing multistage feeding on the performance of Nannochloropsis sp. Sodium bicarbonate, urea, and sodium dihydrogen phosphate monohydrate were used as sources of C, N, and P for the microalgae. The nutrient feeding needed was calculated based on a molecular formula of microalgae(CO0.48H1.83N0.11P0.01) with a production target 1g.L-1 cell biomass. Element C is an iso-molar. The concentration of N- P varies: corresponding to the mol-fraction of the microalgae cell (as a control) and 10% excess. There were four levels of treatment: A (U0P0); B (U10P0); C (U0P10); and D (U10P10) with three replicants in the batch culture system. Nutrient feeding was conducted in three stages: I (40%); II (30%);and III (30%) and incubated in a neutral environment. Nannochloropsis sp. was able to grow well at a temperature of 24–35°C and an acidity level (pH) of 9.0–10.5. The culture (on the 21st day) produced DCW 0.93; 1.04; 0.86;1.12g.L-1, Chlorophyll-a 7.08; 7.62; 4.64; 6.85% DC, lipid 19.2; 15.5; 27.3; and 21.6% DC for treatments A; B;C; and D, respectively.The maximum lipid level resulted in an N deficiency and a P surplus (C). The lipids of the Nannochloropsis sp. composed of 66.0–81.1% saturated fatty acid which is suitable to be used as a biofuel.

scholarly journals PL - 033 A translational model of muscle protein synthetic bioactivity in vitro, ex vivo and in vivo

2018 ◽  
Vol 1 (1) ◽  
Author(s):  
Brian Carson ◽  
Robert Davies ◽  
Joseph Bass ◽  
Catherine Norton ◽  
Bijal Patel ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Stable Isotope ◽  
Resistance Exercise ◽  
Ex Vivo ◽  
Muscle Protein ◽  
Muscle Growth ◽  
Translational Model ◽  
Nutrient Feeding

Objective The aim of this research was the development and validation of a translational model for the evaluation of exercise and nutrient stimulated muscle protein synthesis (MPS). To achieve this overall aim, three primary objectives had to be realised: (i) Development of an in vitro skeletal muscle cell bioassay to measure muscle growth and MPS; (ii) Development of an ex vivo model to evaluate the humoral effect on MPS in response to nutrient feeding and exercise; (iii) Use of a stable isotope technique to evaluate MPS in response to nutrient feeding and exercise in vivo. Methods To develop a novel in vitro skeletal muscle cell bioassay to measure muscle growth and MPS, C2C12 myoblasts were proliferated and subsequently differentiated to myotubes over 8 days in DMEM (2% HS). Changes in cell behavior and adhesion properties were monitored by measuring impedance via interdigitated microelectrodes using the xCELLigence system. MPS was measured by puromycin incorporation using the SUnSET technique, intracellular signalling measured by western blot, and myotube thickness by microscopy. To demonstrate the capability to monitor nutrient regulation of muscle growth, media was conditioned with a known potent regulator of MPS (leucine) in a dose response experiment (0.20 - 2.0 mM). To establish the ability of the bioassay to measure the humoral effect of MPS in response to feeding and exercise, media was conditioned by ex vivo human serum from fasted, rested, fed (protein and isonitrogenous non-essential amino acid (NEAA) control)  and post-exercise conditions. To evaluate MPS in response to nutrient feeding and exercise in vivo, acute MPS (5 h) was assessed by measuring stable isotope deuterium oxide (D2O) incorporation into m. vastus lateralis skeletal muscle following consumption of either a Whey Protein (WP) or an isonitrogenous NEAA control combined with resistance exercise in resistance trained males. Results In vitro experiments observed a dose-response effect with a 32 % increase in cell index and a 27 % increase in cell thickness after 2 h in the presence of 2.0 mM leucine when compared with control myotubes. Ex vivo serum following ingestion of NEAA had no effect on protein signalling or MPS whereas WP fed serum significantly increased mTOR, P70S6K and 4E-BP1 phosphorylation (p<0.01, p<0.05) compared to fasted serum. Furthermore, the effect of WP fed serum on protein signalling and MPS was significantly increased (p<0.01, p<0.05) compared to NEAA fed serum.  Ex vivo human serum following resistance exercise was also increased MPS (29 %) and phosphorylation of mTOR (6 %), p70S6K (12 %) and 4EBP1 (7 %), compared with resting serum. These ex vivo/in vitro findings translated to the in vivo model as myofibrillar fractional synthetic rates (myoFSR) (Basal 0.068±0.002%h-1 vs. WP 0.084±0.006 %h-1, p=0.033) and absolute synthetic rates (ASR) (Basal 10.34±1.01 vs. WP 13.18±0.71 g.day-1, p=0.026) were increased from basal levels only when resistance exercise was combined with WP ingestion and not the NEAA control (NEAA MPS 0.072±0.004%h-1, NEAA ASR 10.23±0.80 g.day-1).  Thus, ingestion of WP in combination with resistance training augments acute MPS responses in resistance trained young men. Conclusions We have developed a translational model of muscle protein synthetic bioactivity using in vitro, ex vivo and in vivo methodologies. We have shown that we can impact MPS in vitro using ex vivo human serum to condition media, that MPS in vitro is differentially regulated by ex vivo serum containing bioactive WP compared to a non-bioactive NEAA control, and that this tranlates for resistance exercise combined with WP in humans when MyoFSR is measured using stable isotope technology.  These experiments demonstrate that ex vivo/in vitro experiments translate to the in vivo model and these methods can be used to inform both exercise and nutrient human interventions. 

scholarly journals Effect of Grain Size and Nutrient Feeding on the Treatment Potential of Biofilters for Treatment of   De-Icing Chemicals

2018 ◽  
Author(s):  
Gema Sakti Raspati ◽  
Hanna Kristine Haug Lindseth ◽  
Tone Merete Muthanna ◽  
Kamal Azrague
Keyword(s):  
Propylene Glycol ◽  
Filtration Rate ◽  
Quality Analysis ◽  
Molar Ratio ◽  
Water Quality Analysis ◽  
Number Of Factors ◽  
Nutrient Feeding ◽  
Filtration Experiment ◽  
The Impact ◽  
Filter Layer

Biofilter application for treatment of stormwater containing de-icing chemicals commonly applied in airports, propylene glycol and potassium formate, was investigated. Lab-scale adsorption tests using filter media made of crushed clay (Filtralite) and granular activated carbon showed that adsorption was unsuitable for removal of propylene glycol and potassium formate. Column filtration experiment testing two different crushed clay size ranges was conducted. The results showed that DOC removal was dependent on a number of factors. This study investigated the impact of filter depth, nutrients addition, and filtration rate. DOC removal suggested that DOC degradation occurred on the top filter layer. It was shown that the most active separation occurred in the first ~20 cm of filter depth. This was confirmed by results from water quality analysis (i.e. DOC removal and ATP measurement) and calculations based on a filtration performance analysis (Iwasaki model) and filter hydraulic evaluation (Lindquist diagram). It was shown that for the highest C:N:P ratio tested (molar ratio of 24:7:1), 50-60% DOC removal was achieved. Addition of nutrients was found important and determining the biofilter performance.

Bioconversion of glycerol to 1,3-propanediol: A mathematical model-based nutrient feeding approach for high production using Clostridium diolis

2013 ◽  
Vol 142 ◽  
pp. 82-87 ◽  
Author(s):  
Guneet Kaur ◽  
A.K. Srivastava ◽  
Subhash Chand
Keyword(s):  
Mathematical Model ◽  
Model Based ◽  
High Production ◽  
Nutrient Feeding
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