Killing cells without lysis in a method for enzyme recovery from a fermentation broth
US5378621A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 7, 1993 |
| Grant date | Jan 3, 1995 |
| Priority date | — |
| Expiry date | May 7, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S530/824
- WIPO fieldBiotechnology
- WIPO sectorChemistry
Abstract
This invention provides a method for killing fungal cells without lysing in fermentation processes in order to prepare the fermentation mixture for processing to recover or extract an extracellularly expressed enzyme from the fermentation mixture. A preferred method of this invention comprises adjusting the pH of the fermentation mixture to less than 2.79 using a mineral acid, then adding sufficient acetic acid to the mixture to affect a substantially complete cell kill in mixture. A salt of the acetic acid can be used. The organic acid or salt can be added, then the pH adjusted to the desired level. Other organic acids can be used, in which case the pH of the mixture is adjusted to the pK.sub.a of the selected organic acid before the organic acid is added to the mixture. The method of this invention is useful for stopping the growth and killing the cells in any micro-organism, culture or fermentation such as those containing yeast, bacteria or fungi and is particularly useful in systems where it is desired to kill the cells without lysing them.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.