TY - JOUR T1 - Optimization of the medium for Lactobacillus acidophilus by Plackett-Burman and steepest ascent experiment A1 - He Chen A1 - Jinfeng Niu A1 - Tao Qin A1 - Qi Ma A1 - Lei Wang A1 - Guowei Shu JO - Acta Sci. Pol. Technol. Aliment VL - 14 IS - 3 SP - 227-232 Y1 - 2015 UR - https://www.food.actapol.net/volume14/issue3/6_3_2015.pdf SN - 1644-0730 KW - Lactobacillus acidophilus, Plackett-Burman experiment, steepest ascent experiment, optimization AB - Background. Lactobacillus acidophilus not only improves the intestinal flora balance but also inhabits the growth of undesirable microorganisms in intestine, which is benefit to the health of humans and animals. Plackett-Burman and steepest ascent experiment are the rapid and concise ways of screening the main effective factors. This study is aimed to select the main influence factors and optimize the medium for Lactobacillus acidophilus by Plackett-Burman experiment and steepest ascent experiment. Material and methods. The ideal carbon source was screened among glucose, maltose, lactose and whey powder, and the ideal nitrogen source was screened among casein hydrolysate, peptone, yeast extract powder, fish meal, carbamide, ammonium sulfate and sodium nitrate by single factor experiment. Plackett-Burman and steepest ascent experiment were applied to screen the main effective factors of Lactobacillus acidophilus among peptone, beef extract, yeast extract powder, glucose, K2HPO4, C6H14O7N2, CH3COONa, MgSO4 and Tween-80. Result. The results indicated that glucose (p = 0.01510) as negative factor and K2HPO4 (p = 0.02017) as positive effect were the significant growth factors of Lactobacillus acidophilus, CH3COONa (p = 0.09273) as positive effect was an important factor, and the optimized medium was as follows: glucose – 21 g/L, K2HPO4 – 3.5 g/L, CH3COONa – 6.5 g/L, peptone – 10 g/L, beef extract – 8 g/L, yeast extract powder – 8 g/L, C6H14O7N2 – 2 g/L, MgSO4 – 0.2 g/L and Tween-80 – 1 mL/L when the maximum viable count could achieve 2.72·109 cfu/mL. Discussion. The experimental model is reliable and the experimental results are of good stability. Variance analysis is performed to determine the adequacy and significance of the linear model. Thus, Plackett-Burman and steepest ascent experiment improve the veracity of optimization the medium for Lactobacillus acidophilus compared with the previous research. ER -