title: Optimization of Cellulase Production by Halobacillus sp. QLS 31 Isolated from Lake Qarun, Egypt.
abstract: A halophilic cellulase-producing bacterium was isolated from a sediment sample collected from Lake Qarun (Fayoum Province, Egypt). Molecular identification based on 16S rDNA amplification and sequencing revealed 99% homology with Halobacillus sp. and hence was designated as Halobacillus sp. QLS 31. Medium composition and culture conditions were optimized for enhancing the production of cellulase enzyme using the Plackett-Burman statistical design. Ten variables were evaluated for their influence on cellulase production. Carboxymethyl cellulose (CMC), zinc sulfate (ZnSO4), and inoculum size were found to exert a significant effect on cellulase productivity by Halobacillus sp. QLS 31. The maximum specific activity of cellulase enzyme was 48.08 U/mg. Following the predicted conditions, a 7.5-fold increase in cellulase specific activity (175.47 U/mg) was achieved compared to the basal medium (23.19 U/mg) under the following optimized conditions: temperature (30 °C), fermentation time (2 days ), pH value (9), CMC concentration (1%), inoculum size (1%), yeast extract concentration (0.1%), ammonium sulfate ((NH3)2SO4) concentration (0.1%), sodium chloride (NaCl) concentration (20%), and metal inducers: ZnSO4(0.1%) and Ca/Mg ratio (0.01%). Thus, the results of this study provide an important basis for more efficient, cheap industrial cellulase production from halophilic Halobacillus sp. QLS 31.
authors.affiliation: Department of Microbiology and Immunology, Faculty of Pharmacy, Nahda University, Beni Suef, 62513, Egypt.
authors.forename: Ahmed H
authors.initials: AH
authors.lastname: Korany
authors.affiliation: Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Kasr El-Aini St., Cairo, 11562, Egypt. amal.ali@pharma.cu.edu.eg.|Department of Microbiology & Immunology, Faculty of Pharmaceutical Sciences & Pharmaceutical Industries, Future University, New Cairo, 12311, Egypt. amal.ali@pharma.cu.edu.eg.
authors.forename: Amal E
authors.initials: AE
authors.lastname: Ali
authors.affiliation: Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Kasr El-Aini St., Cairo, 11562, Egypt.
authors.forename: Tamer M
authors.initials: TM
authors.lastname: Essam
authors.affiliation: Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Kasr El-Aini St., Cairo, 11562, Egypt.
authors.forename: Salwa A
authors.initials: SA
authors.lastname: Megahed
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics; D044602:Cellulases / Q000096:biosynthesis* / Q000235:genetics; D004534:Egypt; D058678:Halobacillus / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification; D060106:Lakes / Q000382:microbiology*; D014871:Water Microbiology
chemical_list: D001426:Bacterial Proteins; D044602:Cellulases
keywords: Cellulase; Halobacillus, Lake Qarun; Halophilic; Plackett-Burman design