title: Optimization of Non-Nutritional Factors for a Cost-Effective Enhancement of Nisin Production Using Orthogonal Array Method.
abstract: In order to increase nisin production in a cost-effective manner, non-nutritional factors as well as nutritional parameters must be optimized. In this study, optimization of the most important non-nutritional factors for nisin production using orthogonal array method was performed. Optimization of temperature, agitation, age and size of inoculum, medium initial pH value and flask volume/medium volume ratio in de Man, Rogosa and Sharpe (MRS) medium in batch fermentation was accomplished. Nisin was produced by Lactococcus lactis subsp. lactis PTCC 1336 and measured by bioassay method using Micrococcus luteus PTCC 1169 as the nisin-sensitive strain. The optimum levels of non-nutritional factors for maximum nisin production and productivity were obtained as: flask volume/medium volume ratio: 5.00, medium initial pH value: 8.00, inoculum size: 1%, inoculum age: 24 h old (A = 1.7), agitation: 100 rpm and temperature: 27 °C. Under the optimized conditions, maximum nisin production and maximum nisin productivity were 599.70 IU/mL and 37.48 IU/mL/h, respectively.
authors.affiliation: Injection Solutions Department, Research and Production Complex, Pasteur Institute of Iran, 25th km Tehran-Karaj Highway, 3159915111, Tehran, Iran. tafreshi@pasteur.ac.ir.
authors.forename: Say-Yed Hesameddin
authors.initials: SY
authors.lastname: Tafreshi
authors.affiliation: Biotechnology Department, Iranian Research Organization for Science and Technology, No. 71, Shahid Mousavi St., Enghelab Ave, Tehran, Iran. Mirdamadi@irost.ir.
authors.forename: Saeed
authors.initials: S
authors.lastname: Mirdamadi
authors.affiliation: Bacterial Vaccines and Antigens Production Department, Pasteur Institute of Iran, 25th km Tehran-Karaj Highway, 3159915111, Tehran, Iran. dnsa@pasteur.ac.ir.
authors.forename: Dariush
authors.initials: D
authors.lastname: Norouzian
authors.affiliation: Biochemistry Department, Pasteur Institute of Iran, No. 69, Karegar Avenue, Pasteur Street, Tehran, Iran. sh-khatami@pasteur.ac.ir.
authors.forename: Shohreh
authors.initials: S
authors.lastname: Khatami
authors.affiliation: Biotechnology Department, Pasteur Institute of Iran, No. 69, Karegar Avenue, Pasteur Street, Tehran, Iran. ssardari@hotmail.com.
authors.forename: Soroush
authors.initials: S
authors.lastname: Sardari
keywords: Batch fermentation; Lactococcus lactis; Optimization; Orthogonal array (OA); Temperature