Đang chuẩn bị liên kết để tải về tài liệu:
Optimization of biosurfactant production by Streptomyces isolated from Egyptian arid soil using Plackett–Burman design

The current study aimed to isolate Streptomyces species from Egyptian arid soil, efficient in biosurfactant production. Fifty isolates of Streptomyces were obtained from arid soil in Egypt. | Annals of Agricultural Science 2015 60 2 209 217 H O S T E D BY Faculty of Agriculture Ain Shams University Annals of Agricultural Science www.elsevier.com locate aoas ORIGINAL ARTICLE Optimization of biosurfactant production by Streptomyces isolated from Egyptian arid soil using Plackett Burman design A.S. Korayem A.A. Abdelhafez M.M. Zaki E.A. Saleh Agric. Microbiology Dept. Fac. Agric. Ain Shams Univ. Cairo Egypt Received 9 August 2015 accepted 28 September 2015 Available online 26 October 2015 KEYWORDS Abstract Surfactants are amphipathic molecules which reduce surface tension widely used in Streptomyces pharmaceutical cosmetic and food industries. The current study aimed to isolate Streptomyces spe- Biosurfactant cies from Egyptian arid soil efficient in biosurfactant production. Fifty isolates of Streptomyces Arid soil were obtained from arid soil in Egypt. Primary screening using lipase drop collapse parafilm M Plackett Burman design and haemolysis tests showed 37 isolates 74 having biosurfactant activity. Secondary screening resulted in 17 isolates based on their activities using emulsification index method. Isolate 5S was selected as the most efficient in biosurfactant production having emulsification index equal to 31.74 . Plackett Burman design was adopted to evaluate the factors affecting biosurfactant pro- duction. Among the tested nine variables of starch nitrate medium treated molasses peptone Tween 80 incubation period and inoculum size were identified as significant factors affecting bio- surfactant production. Cultivation of isolate 5S in the optimized medium elevated biosurfactant production to 42.68 according to emulsification index from 31.74 obtained in un- optimized medium. Ó 2015 Production and hosting by Elsevier B.V. on behalf of Faculty of Agriculture Ain Shams University. This is an open access article under the CC BY-NC-ND license http creativecommons.org licenses by-nc-nd 4.0 . Introduction has an important role in combating environmental .