|
|
| |
| Articles
by
Abdelnasser S.S. Ibrahim |
Total Records (
2 ) for
Abdelnasser S.S. Ibrahim |
|
 |
| |
|
| |
Abdelnasser S.S. Ibrahim
|
| |
Invertebrates are known to be associated with diverse
bacterial population, however, very little is known about the structure,
composition and maintenance of these bacterial communities. In the current
study, we characterize the culturable bacterial community associated with
gorgorian coral Eunicea fusca. This was achieved using culture-based
methods and molecular techniques for the identification of the bacterial
isolates. The culturable heterotrophic bacterial community of this coral
is composed mainly of the bacterial groups Alphaproteobacteria (65.5%),
Gammaproteobacteria (20.7%), Betaproteobacteria (6.9%), Cytophaga-Flexibacter
Bacteroids (3.4%) and Firmicutes (3.4%). This study provides evidence
of specific bacterial association with the coral in comparison to bacterial
community in the coral surrounding seawater. Furthermore, bacterial isolation
using oligotrophic conditions,. at slightly alkaline pH, was found to
increase the culturability and diversity of Eunicea fusca associated
bacteria. |
|
| |
|
| |
Abdelnasser S.S. Ibrahim
and
Ali A. Al-Salamah
|
| |
Media and cultivation conditions were investigated to optimize alkaline protease production by alkaliphilic Bacillus halodurans. This includes different carbon, nitrogen and metals sources in addition to different pH, incubation temperature and aeration level. The specific enzyme activity was increased by about 48.8 fold by optimizing different nutrient sources and cultivation conditions. The maximum specific enzyme activity was obtained in a medium containing 15 g L-1 lactose as the carbon source, 6 g L-1 soybean as the nitrogen source and a 5 mM mixture of Mg, Mn and Ca as trace elements, fermentation for 48 h at 37°C and agitation at 200 rpm. This study indicated the significance of nutrient source and cultivation conditions on the alkaline enzyme production by Bacillus halodurans. |
|
|
|
|
| |
|
