Fermentors equipping

As described in U.S. Patent 2,916,485 12 liters of a nutrient medium having the following composition is placed in a 30 liter fermentor equipped with stainless steel fittings including sparger, impeller, baffles and sampling lines and the medium is sterilized by heating at 121°C for two hours. 

An 8-d old agar slant of Helminthosporium kusanoi Nisik. obtained from CBS (see Table 1) and maintained on oatmeal/ agar, is used to inoculate two 2-L conical flasks each containing 500 mL of nutrient medium. Incubation of the flasks is carried out for 2 d on a rotary shaker (250 rpm, 2.5 cm stroke). The culture obtained is used to inoculate 15 L of nutrient medium in a stainless steel fermentor equipped with stirrer and air inlet (200 rpm. 10 L air/min. 28 °C). 24 h after inoculation, 7.5 g (0.027 mol) of 19-nortestosterone (3) are added as a suspension in 100 mL of sterile water. 48 h laler, conversion of the substrate is complete (monitored by TLC CHC13 acetone 3 1). The mycelial mass is removed by filtration and the filtrate (pH 6.80) is extracted with four 4-L portions of 4-methyl-2-pentanone. After concentration to 100 mL under reduced pressure, the solution is treated with 0.5 g of charcoal. Concentration to 20 mL, cooling and filtration gives crude 4 yield 4.05 g (54%). Recrystallization is from 1.2-dichloroethane/aq ethanol yield 2.30 g (30.6%) mp 213 JC. 

An industrial fermentor of capacity up to several hundred kiloliters equipped with aeration and stirring devices, as well as other automatic control systems, is used. The cultures must be sterilized and aseptic air must be used owing to the high sensitivity to bacterial contamination of L-glutamic acid fermentation. 

To prevent contamination with undesirable microorganisms, the fermentor and auxiUary equipment must be sterilized before inoculation. This is achieved by steam, ie, at least 20 min at 121°C. The incoming air is filtered. 

However, it should be noted that there is a small percentage of the total time in which productivity rate is near its maximum. It is sometimes possible to maintain very high rates of products for a long time with continuous fermentation. Although it can get much more productivity from the fermentor, enhancement over batch fermentation in terms of the total volume of fermentor is not high because equipment needs to be sterilized to support the continuous tank. 

Stirred (agitated) tanks, which are widely used as bioreactors (especially as fermentors), are vertical cylindrical vessels equipped with a mechanical stirrer (agitator) or stirrers that rotate around the axis of the tank. 

A fermentation broth contained in a batch-operated stirred-tank fermentor, 2.4m in inside diameter D, is equipped with a paddle-type stirrer of diameter (L) of 0.8 m that rotates at a speed Af = 4s -. The broth temperature is maintained at 30 °C with cooling water at 15°C, which flows through a stainless steel helical coil that has a 50 mm outside diameter and is 5 mm thick. The maximum rate of heat evolution by biochemical reactions, plus dissipation of mechanical energy input by the stirrer, is 51000 kcal h , although the rate varies with time. The physical properties of the broth at 30 °C were density p = 1000 kg m " , viscosity p = 0.013 Pa s, specific heat Cp = 0.90 kcal kg °C , and thermal conductivity K = 0.49 kcal h m °C = 0.000136 kcals m °C . ... 

Fig. 1. Complete experimental setup for monitoring and control system for fermentor. T, feed tank V, control valve v, valves F, fermentor t, thermocouple c, coils A, dilutions tanks Bm, multichannel pump C, controller Tt, temperature transmitter Tb, biomass transmitter Sb, biomass optical sensor D, equipment to remove air bubbles R, rotammeter Ft, tangential filter Co, computer So, ethanol colorimetric sensor Vi, injection valve d, waste E+R, reagents-enzymes tanks B, pumps.

Since the characteristics of microbes lead to the batch production of many products, examples of fermentors are numerous. They include beer vats, wine casks, and cheese crates as anaerobic food production equipment. The most significant aerobic reactor is the penicillin fermentor. 

The basic raw materials required include starting culture E. coli cells), nutrients (glucose and salts), tryptophan, water, ammonia and air. The process equipment includes fermentor, mixing tank, continuous heat sterilizer, centrifugal compressor, air filter and storage tank. 

The equipment in the solid-state fermentation process is relatively simple and the capital investment is low. However, new types of fermentor for large-scale cellulase production need to be developed. 

From the work presented here, it is clear that IS. coli lysates can be processed with membrane systems, and that specific non aggregated proteins can be quantitatively recovered without significant losses. With our system, membrane processing starts with cells from a fermentor and ends up with a crudely fractionated and concentrated protein solution. This is all accomplished with basically the same equipment and by using both microporous and ultrafiltration membranes. 

For commercial production, the BT cells are grown in large fermentors in complex media that support high cell densities and ultimate sporulation of the cells. Cell lysis releases the spores and crystals into the growth medium, and they are recovered by either centrifugation or other techniques that concentrate the particulates. Depending on the desired formulation, the concentrate is either spray-dried and formulated into wettable powder or oil flowable, or formulated directly from concentrate into an aqueous flowable. Application is with standard spray equipment, either ground or aerial. 

The mathematical modeling of the process consists of mass and energy balance equations. All equipment, except the fermentor, are modeled assuming the hypothesis of pseudo steady state. 

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