pel gene (GenBank: KM244046.1), which encodes Bacillus subtilis pectate lyase (PelB), was high-level expressed in Escherichia coli BL21 (DE3) and the recombinant enzyme was named rePelB. After induction by IPTG at 15 °C for 24 h, specific activity of rePelB in culture supernatant of pCpel-6 reached 197.4 ± 5.20 U/mg. The optima of rePelB were 60 °C and pH 5.0, respectively. Hydrolysis of citrus pectin by rePelB in 50 L grass reactor was optimized by implementing RSM. HPLC analysis revealed molecular mass of citrus pectin and obtained LCP was 290 and 5.8 kDa, respectively. LCP can significantly promote growth of Bifidobacterium longum.

编码枯草芽孢杆菌果胶裂解酶（PelB）的pel基因（GenBank：KM244046.1）在大肠杆菌BL21（DE3）中高表达，重组酶命名为rePelB。在15°C下用IPTG诱导24小时后，pCpel-6培养上清液中rePelB的比活性达到197.4±5.20 U / mg。rePelB的最适温度分别为60°C和pH 5.0。通过实施RSM对rePelB在50 L草反应器中水解柑桔果胶进行了优化。HPLC分析显示柑橘果胶的分子量，得到的LCP分别为290和5.8kDa。LCP可以明显促进长双歧杆菌的生长。