花生壳木犀草素蒸汽爆破预处理工艺优化及结构分析

Optimization of steam explosion pretreatment of peanut shell and its effect on physicochemical properties of luteolin

采用响应面分析法优化花生壳蒸汽爆破预处理工艺,利用扫描电镜对花生壳爆破前后的表皮微观结构进行观察,以大孔吸附树脂AB-8为载体,对花生壳木犀草素粗提物过柱纯化,通过分光光度法、红外光谱和高效液相色谱对纯化后的木犀草素进行定量定性分析。结果表明:爆破压强1.25MPa,维压时间46.0s,含水率16%,该条件下木犀草素得率为0.926%,约为未处理的1.9倍;扫描电镜显示,蒸汽爆破后花生壳的表皮层受到破坏,网状纤维消失,促使纤维素析出并附着在物料表面呈细丝状;蒸汽爆破处理后,纯化产品中木犀草素含量达到32.81%,远高于未爆破处理的产品。蒸汽爆破预处理技术能够明显增加花生壳提取物中木犀草素的提取率。

Box-Behnken design and response surface methodology were employed to optimize the steam explosion process of peanut shell. The microstructure of peanut shell before and after blasting was observed by SEM. Luteolin was further purified by AB-8 macroporous adsorption resin and subsequently analyzed by FT-IR and HPLC, while quantified by UV-Vis spectrophotometry method. The results showed that the optimal steam explosion pressure was 1.25 MPa, and the optimal residence time was 46.0 s , with optimal water content of 16%. Under these conditions, the yield of luteolin was 0.926%, which was 1.9 times that of the untreated peanut shell. The SEM microphotographs showed that the surface layer of peanut shell was broken by the pretreatment of steam explosion, while the lattice-like structure in the shell was removed with the cellulose macro fibers floating above the surface in a smooth pattern. After steam blasting, the content of luteolin in the purified product reached 32.81%, which was much higher than that of the unexploded product. The extraction rate of luteolin from peanut shell extract was significantly increased by steam blasting pretreatment.