Nutrient feeding

Nutraceuticals, 12 61 17 643-683 efficacy of, 17 647-649 future trends in, 17 674 health benefits of, 17 645-649 identification of, 17 646-647 market for, 17 673-674 product classes of, 17 649-673 safety of, 17 647 vitamins as, 17 649-655 NutraSweet, 24 226, 229 Nutrient feeding, for fermentation, 11 39 Nutrient Management Plans, 11 126-127 Nutrient Profiles (AAFCO), 10 857, 858-859t Nutrients... 

A 50,000-gal tank was installed adjacent to the test area. This tank was equipped with an aerator, nutrient feed equipment, and a submersible discharge pump. The physical layout of this system was very similar to that shown in Figure 12.11. 

Information on animal cell metabolism is essential for the formulation of new culture media, as well as for the composition of the most appropriate nutrient feed that may be used in various strategies of batch, semi-batch or continuous culture that may be designed for the production of the targeted protein. As already discussed in detail in Chapter 4 and concisely presented in Figure 5.1, two fundamental substrates for animal cells are glucose and glutamine. 

Wu J, Ruan Q, Peter Lam FfY (1998), Evaluation of spent medium recycle and nutrient feeding strategies for recombinant protein production in the insect cell-baculo-virus process, J. Biotechnol. 66 109-116. 

Parameters that are traditionally used to evaluate the metabolic activity of the cell population inside a hollow-fiber bioreactor include glucose consumption rate (rQLc) and oxygen consumption rate (rcu)- However, these parameters are highly dependent on variations in nutrient feed and metabolic products removal (Gramer et al., 1999). The use of a strategy to overfeed the ICS with nutrients results in a rapid increase in tglc- On the other hand, an increase in product titer and an improved metabolic... 

One of the most popular methods to achieve high cell density is fed-batch culture by controlling the nutrient feeding, which is often necessary for the... 

Nutrition, Zinc is essential to the proper functioning of plants and animals and, as zinc sulfate and oxide, it is used as a feed supplement (49—51) (see Mineral nutrients Feeds and feed additives). Most crops use less than a kilogram of zinc per 1000 m per year, so that zinc salts added at 1.3—4.5 kg/ha gradually build up the zinc reserve (52). Animals, including humans, store relatively Htde available zinc and, thus, require a constant supply in the diet. For instance, beef catde require 10—30 mg/kg dry feed, dairy cattle 40 mg/kg, and breeding hens 65 mg/kg. Zinc from plants is considered less available to monogastric aminals than zinc from animal protein. 

The operation of fermenters is basically the same regardless of size, but seed fermenters usually do not have sterile anti-foam and nutrient feeds piped to the tanks as the main fermenters have. Therefore, foaming in the seed fermenters can lead to infection, which is one of the reasons they need more attention. Careful inoculation procedures, sampling and sterilizing the transfer lines from the seed fermenter require alert personnel. Careful attention to these details is more important than the proximity of the seed and main fermenters. 

Essential equipment to a productive fermentation department are sterilizable tanks for nutrient feeds. Multiproduct plants usually require several different sizes of feed tanks (i) a small volume to be transferred once... 

Small continuous sterilizers are used in fermentation pilot plants as well as for nutrient feeds to a single vessel or group of fermenters. 

Hu, Alteration of mammalian metabolism by dynamic nutrient feeding. Cytotechnology, 1997, 24, 99-108. 

Cell recycle fermentors consist of two main units a vessel where the biomass is allowed to grow, and a membrane separation unit (as in Figure 7.40). Vessels are usually designed to insure a uniform concentration of nutrients and pH throughout the whole volume. Due to complete mixing, process control and stability of the microbial slurry are not difficult to achieve.88 After anaerobic stabilization, when the biomass is well developed, the reactor biomass is pumped to the UF unit where solid-liquid separation occurs. The sludge is flushed back to the reactor. In most cases, the flow rate of nutrient feed is kept equal to the permeate flow rate thus keeping a constant liquid level in the anaerobic reactor. 

Point of nutrient feed initiation Nutrient feeding rate Osmolarity Point of induction... 

Boeck LD, Favret ME, Wetzel RW (1992) Biosynthesis of thiopeptide antibiotic A10255 in stirred reactors using a chemically defined medium supplemented with continuous nutrient feeds. J Antibiot 45 1278-1285... 

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