Optimization of Protease Production by Psychrotrophic Rheinheimera sp. with Response Surface Methodology
<p><strong>Background and Objectives:</strong> Psychrotrophic bacteria can produce enzymes at low temperatures; this provides a wide biotechnological potential, and offers numerous economical advantages over the use of mesophilic bacteria. In this study, extracellular protease prod...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Shahid Behehsti University of Medical Sciences
2016-10-01
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| Series: | Applied Food Biotechnology |
| Subjects: | |
| Online Access: | http://journals.sbmu.ac.ir/afb/article/view/12776 |
| _version_ | 1819264381868834816 |
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| author | Mrayam Mahjoubin-Tehran Bahar Shahnavaz Razie Ghazi-Birjandi Mansour Mashreghi Jamshid Fooladi |
| author_facet | Mrayam Mahjoubin-Tehran Bahar Shahnavaz Razie Ghazi-Birjandi Mansour Mashreghi Jamshid Fooladi |
| author_sort | Mrayam Mahjoubin-Tehran |
| collection | DOAJ |
| description | <p><strong>Background and Objectives:</strong> Psychrotrophic bacteria can produce enzymes at low temperatures; this provides a wide biotechnological potential, and offers numerous economical advantages over the use of mesophilic bacteria. In this study, extracellular protease production by psychrotrophic Rheinheimera sp. (KM459533) was optimized by the response surface methodology.</p><p><strong>Materials and Methods:</strong> The culture medium was tryptic soy broth containing 1% (w v -1 ) skim milk. First, the effects of variables were independently evaluated on the microbial growth and protease production by one-factor-at-a-time method within the following ranges: incubation time 24-120 h, temperature 15-37°C, pH 6- 11, skim milk concentration 0-2% (w v -1 ), and inoculum size 0.5-3% (v v -1 ). The combinational effects of the four major variable including temperature, pH, skim milk concentration, and inoculum size were then evaluated within 96 h using response surface methodology through 27 experiments.</p><p><strong>Results and Conclusion:</strong> In one-factor-at-a-time method, high cell density was detected at 72h, 20°C, pH 7, skim milk 2% (w v -1 ), and inoculum size 3% (v v -1 ), and maximum enzyme production (533.74 Uml-1 ) was achieved at 96h, 20°C, pH 9, skim milk 1% (w v -1 ), and inoculum size 3% (v v -1 ). The response surface methodology study showed that pH is the most effective factor in enzyme production, and among the other variables, only temperature had significant interaction with pH and inoculum size. The determination coefficient (R2 =0.9544) and non-significant lack of fit demonstrated correlation between the experimental and predicted values. The optimal conditions predicted by the response surface methodology for protease production were defined as: 22C, pH 8.5, skim milk 1.1% (w v -1 ), and inoculum size 4% (v v -1 ). Protease production under these conditions reached to 567.19 Uml-1 . The use of response surface methodology in this study increased protease production by eight times as compared to the observed before optimization.</p><p><strong>Conflict of interests:</strong> The authors declare no conflict of interest.</p> |
| first_indexed | 2024-12-23T20:28:35Z |
| format | Article |
| id | doaj.art-973444e9aea44574b46555d6204c1f90 |
| institution | Directory Open Access Journal |
| issn | 2345-5357 2423-4214 |
| language | English |
| last_indexed | 2024-12-23T20:28:35Z |
| publishDate | 2016-10-01 |
| publisher | Shahid Behehsti University of Medical Sciences |
| record_format | Article |
| series | Applied Food Biotechnology |
| spelling | doaj.art-973444e9aea44574b46555d6204c1f902022-12-21T17:32:19ZengShahid Behehsti University of Medical SciencesApplied Food Biotechnology2345-53572423-42142016-10-01342362457590Optimization of Protease Production by Psychrotrophic Rheinheimera sp. with Response Surface MethodologyMrayam Mahjoubin-Tehran0Bahar Shahnavaz1Razie Ghazi-Birjandi2Mansour MashreghiJamshid Fooladi3Department of Biology, Faculty of Science, Ferdowsi University of MashhadDepartment of Biology, Faculty of Science, Ferdowsi University of MashhadDepartment of Biology, Faculty of Science, Ferdowsi University of MashhadDepartment of Biotechnology, Faculty of Science, Alzahra University<p><strong>Background and Objectives:</strong> Psychrotrophic bacteria can produce enzymes at low temperatures; this provides a wide biotechnological potential, and offers numerous economical advantages over the use of mesophilic bacteria. In this study, extracellular protease production by psychrotrophic Rheinheimera sp. (KM459533) was optimized by the response surface methodology.</p><p><strong>Materials and Methods:</strong> The culture medium was tryptic soy broth containing 1% (w v -1 ) skim milk. First, the effects of variables were independently evaluated on the microbial growth and protease production by one-factor-at-a-time method within the following ranges: incubation time 24-120 h, temperature 15-37°C, pH 6- 11, skim milk concentration 0-2% (w v -1 ), and inoculum size 0.5-3% (v v -1 ). The combinational effects of the four major variable including temperature, pH, skim milk concentration, and inoculum size were then evaluated within 96 h using response surface methodology through 27 experiments.</p><p><strong>Results and Conclusion:</strong> In one-factor-at-a-time method, high cell density was detected at 72h, 20°C, pH 7, skim milk 2% (w v -1 ), and inoculum size 3% (v v -1 ), and maximum enzyme production (533.74 Uml-1 ) was achieved at 96h, 20°C, pH 9, skim milk 1% (w v -1 ), and inoculum size 3% (v v -1 ). The response surface methodology study showed that pH is the most effective factor in enzyme production, and among the other variables, only temperature had significant interaction with pH and inoculum size. The determination coefficient (R2 =0.9544) and non-significant lack of fit demonstrated correlation between the experimental and predicted values. The optimal conditions predicted by the response surface methodology for protease production were defined as: 22C, pH 8.5, skim milk 1.1% (w v -1 ), and inoculum size 4% (v v -1 ). Protease production under these conditions reached to 567.19 Uml-1 . The use of response surface methodology in this study increased protease production by eight times as compared to the observed before optimization.</p><p><strong>Conflict of interests:</strong> The authors declare no conflict of interest.</p>http://journals.sbmu.ac.ir/afb/article/view/12776Cold-tolerantOptimizationProtease productionRheinheimera sp. |
| spellingShingle | Mrayam Mahjoubin-Tehran Bahar Shahnavaz Razie Ghazi-Birjandi Mansour Mashreghi Jamshid Fooladi Optimization of Protease Production by Psychrotrophic Rheinheimera sp. with Response Surface Methodology Applied Food Biotechnology Cold-tolerant Optimization Protease production Rheinheimera sp. |
| title | Optimization of Protease Production by Psychrotrophic Rheinheimera sp. with Response Surface Methodology |
| title_full | Optimization of Protease Production by Psychrotrophic Rheinheimera sp. with Response Surface Methodology |
| title_fullStr | Optimization of Protease Production by Psychrotrophic Rheinheimera sp. with Response Surface Methodology |
| title_full_unstemmed | Optimization of Protease Production by Psychrotrophic Rheinheimera sp. with Response Surface Methodology |
| title_short | Optimization of Protease Production by Psychrotrophic Rheinheimera sp. with Response Surface Methodology |
| title_sort | optimization of protease production by psychrotrophic rheinheimera sp with response surface methodology |
| topic | Cold-tolerant Optimization Protease production Rheinheimera sp. |
| url | http://journals.sbmu.ac.ir/afb/article/view/12776 |
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