L fermentation

Worldwide ethanol demand in 1991 was about 19 x 10 L, of which the industrial demand was about 5 x 10 L. The majority of the worldwide demand was for fuel use with Brazil consuming 11.9 X 10 L in 1989 (239) and the United States consuming 3.6 X 10 L in 1990 (240). In 1991, worldwide synthetic ethanol capacity amounted to 2.04 x 10 L, with the United States having a capacity of 0.802 x 10 L, 39% of the world total (Table 2). In 1991, the total ethanol capacity in the United States was 4.67 x 10 L with an industrial demand of 0.908 x 10 L. Fermentation alcohol and imports suppHed the remainder of the industrial market not suppHed by synthetic alcohol. 

L to 190,000 L fermenters combined with the required downstream recovery and purification lines, which render FDA-GMP quality enzyme products. 

For the expression of PAMO-P3, 100 mL of an overnight preculture of E. coli TOPIO [pPAMO-P3] in terrific broth medium supplemented with 100 mg of carbenicillin was used to inoculate 5 L terrific broth medium supplemented with 100 mg of carbenicillin and 0.1 % L-arabinose in a 5 L fermenter. The expression was carried out... 

Expression of YqjM was carried out in a 5 L fermenter using terrific broth medium supplemented with 100 mg carbenicillin. As an inoculum, 100 mL of preculture was... 

Procedure 4 Scale-up Synthesis of (S)-7-Methyl-2-oxepanone in a 3 L Fermenter... 

Culture and bioconversion. The precultured cells were recovered by centrifugation at 4 °C and the cell pellet was inoculated into a 3 L fermenter (stirred tank with two Rushton turbine impellers and four baffles) containing 1.0 L of supplemented M9 medium. 

Examples Lonza invested 275 million for addition of 60,000-L fermenter volume in Portsmouth, NH, corresponding to = 4.58 million/m ). 

B. Riebel, Dissertation, University of Dtisseldorf, 1996. A 10 L fermentation of E. coli strain recADH-HBlOl-l- yields approximately 500 000 U of recLBADH. LBADH was used in the form of a crude cell extract (recLBADH) from a recombinant E. coli strain. 

As a result of the high natural acidity in the native and hybrid grapes, the malo-lactic (M-L) fermentation is of particular significance in the production of quality wine from this fruit. A survey of New York State wines in 1964 (60) revealed that 45% had undergone the M-L fermentation, including 68% of the reds and 27% of the whites. This... 

Cellar practices were shown to influence the extent of M-L fermentation in Eastern wines (60). The highest incidence occurred where must was fermented immediately after pressing. The lowest incidence was found where only a portion of the must was fermented immediately and the remainder was pasteurized, cooled, and held in cold storage until fermenter space became available. The effect of sulfur dioxide concentration on incidence of M-L fermentation was not evaluated in that survey. 

The M-L fermentation causes several beneficial changes in these high acid, low pH wines, among them a decrease in acidity and an increase in the pH. The effect of the conversion of malic acid to lactic acid on the total acidity of native and hybrid wines is shown in Table VIII. The total acidity decreased to the range 0.6-0.8 gram/100 ml which is considered desirable in these native wines. This conversion is of particular significance in regard to flavor since lactic is less sour than malic at the same titratable acidity and the same pH (63). 

The rise in pH which normally accompanies the M-L fermentation was observed. Although the pH change in Delaware and Niagara, was minimal in 1972, a study of specific lots of Delaware, Niagara, and Elvira in 1969 ( 64) indicated that the initial pH values of 2.90-3.10 increased to 3.25-3.50 on completion of the M-L fermentation. This shift is important since the very tart sensation imparted by wines of low pH changes significantly as the pH is raised (63). 

Temperature and pH influence the rate at which the M-L fermentation proceeds. By determining cell numbers in the new wine at weekly intervals (60, 64), the generation time (g) of the lactic culture during the M-L fermentation was calculated. Extreme growth rates in terms of generation time (g) together with the related pH and temperature data are shown in Table X. Generation time varied widely with different combinations of temperature and pH. 

Figure 3. Relationship of bacterial growth, expressed as generation time (g) to pH and temperature of wine during M-L fermentation...

The rate at which the M-L fermentation proceeds is a function of the generation time. As pH and temperature decrease, the generation time increases, and the M-L fermentation proceeds more slowly. These observations agree with the conclusions of Bousbouras and Kunkee (65) in relation to the effect of pH on the rate of M-L fermentation. Even at the low pH values observed in some of the native white wines, Leuco-nostoc organisms were able to develop and complete the M-L fermentation. The cool cellar temperatures did not inhibit the M-L fermentation... 

Rankine et al. (70) observed in Australian wines that the critical factor governing growth of lactics in wine was sulfur dioxide content. These studies of the M-L fermentation in native American and hybrid wines seem to confirm this observation. With the range of pH and temperature noted for these wines, the M-L fermentation occurred quite regularly as long as the free sulfur dioxide content was low (20 ppm or less). However, no growth of lactics was found if levels of free sulfur dioxide approached or exceeded 50 ppm. 

The optimum agitation speed for the cultivation of plant cells in a 3-L fermenter equipped with four baffles was found to be 150 rpm. 

Improvement step Improvement process Shake flask (mg/L) Fermenter ( mg/L)... 

Composition of the adhesive One part spray-dried, milled sulfite liquor containing ca. 20% sugar and 1.5 parts concentrated culture filtrate of Trametes versicolor (grown on 0.1% organosolv lignin in a 25 L fermenter), containing 420 U/mL phenoloxidase activity. 

In order to provide material for synthetic chemistry and for further analysis, two 50 L fermentations were carried out. After a 20-hour lag phase the titre of the major active species SB-253514 (3b) steadily increased and was accompanied by a drop in pH (Fig. 1, Profiles for two 50 L cultures). Following a plateau in accretion of SB-253514 at 78 hours, the culture was pasteurised by heating to 75 C then the broth was cooled. 

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