Mabrouk Sameh Ben, Hmida Bouthaina Ben Hadj, Sebii Haifa, Fendri Ahmed, Sayari Adel
Laboratory of Biochemistry and Enzymatic Engineering of Lipases, Engineering National School of Sfax (ENIS), University of Sfax, 3038 Sfax, Tunisia.
Laboratory of Biochemistry and Enzymatic Engineering of Lipases, Engineering National School of Sfax (ENIS), University of Sfax, 3038 Sfax, Tunisia.
Int J Biol Macromol. 2025 Jan;285:138147. doi: 10.1016/j.ijbiomac.2024.138147. Epub 2024 Nov 27.
Using the statistical approaches, the optimization of amylase production by a newly Bacillus strain was achieved. Keeping the insignificant factor at lower levels and following the optimized condition (inoculum size 0.3; 19 h of incubation; 18 g L of starch; 4 g L of MgSO; and 15 g L NaCl) the amylase activity has reached 18.48 ± 0.42 U mL with an improvement factor of 6.48-fold-times. The properties of the crude amylase, tentatively named AmySBM, were examined, revealing an optimal activity at 60 °C and pH 7. The enzyme demonstrated good stability across a wide temperature range (40-60 °C) and pH levels (6-7). Its activity depended on the presence of Ca. Additionally, it was discovered that maltose was the sole product of starch hydrolysis by AmySBM, an encouraging result for introducing it into bread making. Tests on dough properties with varied amylase amounts revealed that 0.06 U g was ideal, with white flour producing the greatest results. Incorporating Rhizopus oryzae lipase at 1.2 U g dramatically increased bread quality. Finally, combining an enzymatic cocktail of AmySBM and lipase at optimal quantities improved the qualities of white bread, demonstrating its potential as an anti-staling agent to replace conventional improvers in the baking industry.
通过统计方法,实现了对一株新的芽孢杆菌菌株淀粉酶产量的优化。将不显著的因素保持在较低水平,并遵循优化条件(接种量0.3;培养19小时;淀粉18 g/L;MgSO4 4 g/L;NaCl 15 g/L),淀粉酶活性达到18.48±0.42 U/mL,提高了6.48倍。对初步命名为AmySBM的粗淀粉酶的性质进行了研究,结果表明其在60°C和pH 7时具有最佳活性。该酶在较宽的温度范围(40-60°C)和pH水平(6-7)内表现出良好的稳定性。其活性依赖于Ca的存在。此外,还发现麦芽糖是AmySBM水解淀粉的唯一产物,这对于将其引入面包制作来说是一个令人鼓舞的结果。对不同淀粉酶用量的面团性质进行测试表明,0.06 U/g是理想用量,使用白面粉时效果最佳。添加1.2 U/g的米根霉脂肪酶可显著提高面包品质。最后,将AmySBM和脂肪酶以最佳用量组合成酶混合物,可改善白面包的品质,证明了其作为抗老化剂替代烘焙行业传统改良剂的潜力。