Optimization of Trypsin-like Protease Production by Lactobacillus plantarum FNCC 0270 using Response Surface Methodology

The purpose of this study was to get optimum medium composition and agitation to trypsin-like protease production by Lactobacillus plantarum FNCC 0270. The medium composition and agitation for enzyme production was optimized using Central Composite Design and Response Surface Method with Design Expert software version 7.1.5. Fermentation was carried out in erlenmeyer flask at initial pH 8, 37 °C, with shaker incubator at 87.5 rpm. The results of the best of enzyme activity 1.0 mU/mL, protein levels of 0.557 mg/mL and desirability value of 0.740. Numerical optimization was performed to approach the ideal state of the fermentation or desirability value of 1. The medium composition of fermentation used was: 3.64% baker s yeast, 1.21% glucose, and 0.13% skim milk. The enzyme activity reached was 1.51 mU/mL and protein levels of 0.205 mg/mL. After numerical optimization, the fermentation process was verified using 125 mL Erlenmeyer in shaking incubator at 77 rpm, initial pH 8, 37 °C, 15 h of fermentation. The verification results showed that the enzyme activity and protein levels was 1.273 ± 0.227 mU/mL and 0.248 ± 0.012 mg/mL, respectively.