IMPROVEMENT OF ETHANOL PRODUCTION BY SACCHAROMYCES CEREVISIAE USING MICROBIAL BIOTECHNOLOGY TECHNIQUES
Abd El-Nasser Abd El-Hafez Khattab;
Abstract
The present study was designed to obtain highly ethanol producing isolates of Saccharomyces cerevisiae via induced mutants and protoplast fusion techniques. The obtained results could be summarized as follows:
1- Eleven different Saccharomyces strains were collected from National
or International microbiology labs. Determination of their ethanol productivity was carried out. The diploid strainS. cerevisiae (No. 1 0) proved to be the highest producing one, more ethanol tolerant, and it was considered as the thermotolerant strain in comparison with the other collected strains. Therefore, it was used in the following studies as the original strain.
2- Generally, isolation of a haploid yeast from diploid yeast (No. 10) is an important protocol in order to study the effect of haploidization on ethanol productivity. Higher differences in ethanol productivity was found among haploid strains. Some of these haploid isolates (No. 1, 2,
4, 5, 9, 12, 14, 17 and 25) yielded nearly more ethanol than the original strain. Moreover, other haploids proved to produce the same or less ethanol than the original strain.
3- Application of ultraviolet light as a mutagen with different exposure times followed by incubation in dark for two hours, led to the picking of 161 isolates. The following results were obtained:
3-a- The survival percentage decreased gradually while exposure time increased.
3-b- The highest number of auxotrophs was obtained following 15 min. exposure time, while higher morphological variations were noticed after 10 min. exposure time.
1- Eleven different Saccharomyces strains were collected from National
or International microbiology labs. Determination of their ethanol productivity was carried out. The diploid strainS. cerevisiae (No. 1 0) proved to be the highest producing one, more ethanol tolerant, and it was considered as the thermotolerant strain in comparison with the other collected strains. Therefore, it was used in the following studies as the original strain.
2- Generally, isolation of a haploid yeast from diploid yeast (No. 10) is an important protocol in order to study the effect of haploidization on ethanol productivity. Higher differences in ethanol productivity was found among haploid strains. Some of these haploid isolates (No. 1, 2,
4, 5, 9, 12, 14, 17 and 25) yielded nearly more ethanol than the original strain. Moreover, other haploids proved to produce the same or less ethanol than the original strain.
3- Application of ultraviolet light as a mutagen with different exposure times followed by incubation in dark for two hours, led to the picking of 161 isolates. The following results were obtained:
3-a- The survival percentage decreased gradually while exposure time increased.
3-b- The highest number of auxotrophs was obtained following 15 min. exposure time, while higher morphological variations were noticed after 10 min. exposure time.
Other data
| Title | IMPROVEMENT OF ETHANOL PRODUCTION BY SACCHAROMYCES CEREVISIAE USING MICROBIAL BIOTECHNOLOGY TECHNIQUES | Other Titles | تحسين انتاجية كحول الايثايل من خميرة الخباز باستخدام تكنيكات التكنولوجيا الحيوية الميكروبية | Authors | Abd El-Nasser Abd El-Hafez Khattab | Issue Date | 1997 |
Recommend this item
Similar Items from Core Recommender Database
Items in Ain Shams Scholar are protected by copyright, with all rights reserved, unless otherwise indicated.