Chemistry: molecular biology and microbiology – Enzyme – proenzyme; compositions thereof; process for... – Hydrolase
Patent
1990-08-13
1993-10-26
Naff, David M.
Chemistry: molecular biology and microbiology
Enzyme , proenzyme; compositions thereof; process for...
Hydrolase
435814, C12N 926
Patent
active
052565564
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to methods of preparing invertase from yeast.
2. Brief Description of the Related Art
Invertase is contained within the cells of various yeasts. In order to obtain the enzyme, which is employed on the industrial scale in the foodstuffs industry, it is necessary to disrupt the yeast cells. This is followed by removal of the cell detritus and undesired proteins.
Invertase is distinguished by an above-average resistance to heat and low pH values. Based on this, a process for obtaining invertase has already been proposed, in which a heat treatment is carried out at a pH of 5.0, but this yields a purification factor of only 2. It is therefore not surprising that the method of obtaining invertase in practice does not make use of this process which was proposed as long ago as 1967; N.P. Neumann and J.O. Lampen, Biochemistry 6 (1967), 468-475 . On the contrary, the classical working up of invertase provides for two acetone-precipitation steps; cf., for example, Ullmanns Enzyklopadie der technischen Chemie; H. Vetter et al. "Enzyme", in: Ullmanns Enzyklopadie der technischen Chemie, Vol. 10, pp. 475-561 Verlag Chemie, Weinheim, 1975.
A process proposed in a Japanese patent (S. Takai et al., Japan. Patent, JP 45/9824 [70/9824], Apr. 9, 1970) also has a similar procedure:
In this case 30-hour cell lysis and acid treatment at pH 4.5 are followed by filtration and then acetone precipitation and finally extraction. A process proposed by other authors (E. Matulaityte and V. Avizienis, Matr. Biokhim. Konf. Pribalt. Resp. B. SSR, 5th, Volume 2, 14-15, Editor I.K. Sibul Akad. Nauk. Est. SSR: Tallin, USSR) is also very similar to this process.
SUMMARY OF THE INVENTION
The inventors have now re-examined the state of the art, which in the opinion of experts leads no further and has thus been given up, and in doing so have found that surprisingly high purification factors can be achieved and, in addition, clarification is possible more easily by centrifugation when particular measures are taken into consideration. A process for obtaining invertase from yeast is now proposed according to the invention, in which the yeast cells are disrupted, the disrupted cell suspension is subjected in a strongly acid medium to a heat treatment, and the denatured undesired proteins are removed with the cell detritus, preferably by centrifugation, and then the invertase is isolated where appropriate, this process being characterized in that
the disrupted cell suspension is subjected at a pH of less than 4.5
to a heat treatment at a temperature in the range from 40.degree. to 60.degree. C., or in that
the disrupted cell suspension is subjected to an acid treatment at a pH of less than or equal to 4.0 without heat treatment.
Preferably used in the heat treatment is a temperature in the range from 45.degree. to 50.degree. C. at a pH in the range from 3.0 to 4.2, with a temperature of 48.degree. to 50.degree. C. and the pH range 3.8 to 4.2 being particularly preferred.
Suitable yeasts are brewer's yeast, baker's yeast or yeasts derived therefrom, or microorganisms which contain the genetic information for the production of brewer's yeast invertase or baker's yeast invertase.
It is possible with the process according to the invention to produce virtually particle-free supernatants, for example, in a subsequent centrifugation. Another advantage may be regarded as being the possibility of using virtually no chemicals. The treatment can be carried out with acids approved for foodstuffs, for example phosphoric acid or acetic acid. Undesired concomitant enzymes can be virtually completely inactivated.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graphical representation of the enzyme activity and protein content of preparations subjected to acid and heat treatment.
FIG. 2 is a graphical representation of yield and purity of preparations subjected to heat treatment (pH=6.0).
FIG. 3 is a graphical representation of yield and purity of preparations subjected to heat-treatment
REFERENCES:
patent: 1689607 (1928-10-01), Wickenden
patent: 1855591 (1932-04-01), Wallerstein
patent: 1855592 (1932-04-01), Wallerstein
patent: 1919675 (1933-07-01), Wallerstein
patent: 1919676 (1933-07-01), Wallerstein
patent: 1990505 (1935-02-01), Wallerstein
patent: 2164936 (1939-07-01), Miller et al.
patent: 3427223 (1969-02-01), Frankenfeld et al.
patent: 3887434 (1975-06-01), Frominer et al.
patent: 4278764 (1981-07-01), Rottighi et al.
patent: 4925796 (1990-05-01), Bergh et al.
Cheremisinoff et al., Biotechnology: Applications and Research, 1985, pp. 534-546.
Borner Bernhard
Buntemeyer Kay
Hustedt Helmut
Kroner Karl-Heinz
Gesellschaft fur Biotechnologische Forschung GmbH (GBF)
Meller Mike
Naff David M.
LandOfFree
Process for obtaining invertase from yeast does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for obtaining invertase from yeast, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for obtaining invertase from yeast will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-958699