从苋菜中提取氢过氧化物裂解酶工艺

Extraction Technology of Hydroperoxide Lyase from Amaranth tricolor

在高等植物中,氢过氧化物裂解酶(hydroperoxide lyase,HPL)可将脂肪氧合酶氧化多不饱和脂肪酸产生的氢过氧化物催化裂解,生成的己醛、己烯醛等芳香性物质具有果蔬的新鲜气味,是食品行业和日化工业中的重要芳香风味添加剂。实验以苋菜为研究对象,在单因素[pH、半胱氨酸浓度、匀浆转速、聚乙烯吡咯烷酮(PVP)浓度]实验基础上,运用4因素3水平的正交实验,对HPL的提取工艺进行了优化,即在12 000 r/min,以pH 8.0的含有1 mmol/L半胱氨酸和0.3%质量浓度的PVP为缓冲液提取HPL,得到的HPL具有很高的酶活。并探索了抽真空对HPL提取的影响,在抽真空完全除去氧的情况下提取HPL,酶活得到显著提高。

In higher plant,hydroperoxide lyase（HPL） catalyzed the cleavage of hydroperoxide,which converted from linoleic or linolenc acid by LOX,to give C6 volatile aldehyes together with ω–oxoacids.These volatile aldehydes are important contributors to the distinctive scent of fresh fruits and vegetables,C6 aldehydes are an important flavor additive in food industry and chemical industry.Based on the single-factor tests,combination of the extraction parameters was optimized by using four-factor-three-level orthogonal test.The optimum conditions were determined as follows： speed 12 000r/min,pH =8.0,contained 1mmol / L cysteine and 0.3%（m / v） PVP as a buffer.Under that condition,the total enzyme activity of HPL was high.We also explored the effect of the vacuum the extraction of HPL and found that if the HPL was extracted under the condition of complete oxygen removal,its total enzyme activity would be significantly improved.