title: Application of response surface methodology in the optimisation of a growth medium for enhanced natural preservative bacteriocin production by a probiotic bacterium.
abstract: In this study, a statistics-based experimental design was utilised for the optimisation of a growth medium which possibly enhanced bacteriocin production by Streptococcus phocae PI80. Carbon, nitrogen sources and a bio-surfactant were first screened using a one variable at a time technique and scored for increasing yield production. The selected variables were further statistically optimised using response surface methodology with a central composite design. The high- and low-level limits of the selected variables were determined, and a set of 34 experimental runs were performed. The concentration of each medium ingredient influenced the bacteriocin activity to about 22,500 AU mL⁻¹. The carbon and nitrogen sources were identified as significant factors in restraining the bacteriocin activity produced by S. phocae PI80. The statistics-based experimental design was found to be very efficient in optimising the media components in a number of experimental runs, with a three-fold increase in bacteriocin activity compared to the un-optimised medium. The optimum medium composition was found to be sodium succinate (10.0 g L⁻¹), yeast extract (4.0 g L⁻¹), glucose (9.0 g L⁻¹), NaCl (10.0 g L⁻¹), Tween 80 (6.0 g L⁻¹) and K₂HPO₄ (1.0 g L⁻¹). This optimised medium is two-fold more cost effective than the commercial Lactobacillus MRS medium.
authors: Department of Biotechnology, School of Life Sciences, Pondicherry University, Pondicherry 605014, India.
authors: Paulraj
authors: P
authors: Kanmani
authors: R Satish
authors: RS
authors: Kumar
authors: N
authors: N
authors: Yuvaraj
authors: K A
authors: KA
authors: Paari
authors: V
authors: V
authors: Pattukumar
authors: Venkatesan
authors: V
authors: Arul
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D001430:Bacteriocins / Q000096:biosynthesis*; D008828:Microbiological Techniques / Q000379:methods*; D019936:Probiotics / Q000378:metabolism*; D013291:Streptococcus / Q000378:metabolism
chemical_list: D001430:Bacteriocins