Subscribe Now Subscribe Today
Science Alert
 
Blue
   
Curve Top
Pakistan Journal of Biological Sciences
  Year: 2000 | Volume: 3 | Issue: 10 | Page No.: 1762-1768
DOI: 10.3923/pjbs.2000.1762.1768
 
Facebook Twitter Digg Reddit Linkedin StumbleUpon E-mail

Studies on Activation of Amylolytic Enzymes Production by Gamma Irradiated Aspergillus niger Using Some Surfactants and Natural Oils under Solid State Fermentation

Fadel M. and A. I. El - Batal

Abstract:
Active enhanced isolates producing high levels of amylolytic enzymes were obtained by gamma irradiation of the wild type Aspergillus niger F-909. The potent isolate No. 44e was derived from 0.8 kGy treated group grown on radicle (a waste of malt beverage industry) containing medium under solid state fermentation (SSF) conditions. The potent isolate exhibited enhanced production of alpha-amylase (EC 3.2. 1.1), glucoamylase (EC 3.2. 1.3) and alpha-glucosidase (EC 3.2.1.20), with relative increase in activities over the parental strain as reaching 111.3, 117.4 and 140% respectively. A study was conducted on this isolate to assess the effect of supplementation of radicle medium with low levels of five surfactants namely Tween 20, Tween 40, Tween BO, Tween 80 and Triton X-100 and four plant oils i.e. cotton seed, maize, soybean and sunflower on the enzymes synthesis under SSF conditions. The enzyme levels were considerably increased in the presence of Tween 80 at level 0.2% (v/v). Several solvent systems were evaluated with respect to their extraction abilities of the fungus amylolytic enzymes grown on the solid state culture. The most efficient extracting solvent proved to be tap water adjusted to pH 3.5. Furthermore, the extraction temperature, contact time and shaking speed affected the extraction process. Purification folds of 10.2, 10.4 and 11.9 for alpha-amylase, glucoamylase and alphaglucosidase were obtained by partial purification through precipitation with 65% saturation ammonium sulphate. Application studies were carried out on the partially purified enzyme of the potent isolate No. 44e which was used to hydrolyze native raw starch as a substrate wherein about 97% saccharification for 20% slurry of raw potato starch was achieved after 14h. Furthermore and in complementary experiments 8.6% (vlv) ethanol yield was produced from 18% (w/v) starch hydrolyzate when -fermentation studies were carried out with Saccharomyces cerevisiae after 24 h at 36°C. Yeast biomass of 21.3 g L–1 was produced when the culture conditions using the starch hydrolyzate were modified to obtain microbial protein production.
PDF Fulltext XML References Citation Report Citation
How to cite this article:

Fadel M. and A. I. El - Batal, 2000. Studies on Activation of Amylolytic Enzymes Production by Gamma Irradiated Aspergillus niger Using Some Surfactants and Natural Oils under Solid State Fermentation. Pakistan Journal of Biological Sciences, 3: 1762-1768.

DOI: 10.3923/pjbs.2000.1762.1768

URL: https://scialert.net/abstract/?doi=pjbs.2000.1762.1768

COMMENT ON THIS PAPER
 
 
 

 

 
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 
 
 
 

Curve Bottom