海参肠道产蛋白酶菌的分离鉴定及其在海参下脚料中的应用

Isolation and identification of protease-producing bacterium in intestinal tract of sea cucumbers and its applications in treating sea cucumber residues

以1株海参肠道产蛋白酶菌为研究对象,通过正交试验优化了该菌发酵产多肽的最佳工艺条件。对其进行形态学、生理生化特性、分子生物学16S rDNA序列同源性分析,确定该菌株隶属芽孢杆菌目,命名为Thalassobacillus sp.QDHF-1。利用QDHF-1发酵海参肠,以多肽含量为指标优化发酵条件,并对发酵产物多肽进行了抗氧化活性测定,确定对发酵海参肠产多肽的最佳工艺条件为接种量6%,料水比1∶5(g∶mL),发酵时间36 h;海参肠发酵产物多肽对·OH,DPPH·,O2^-·3种自由基均有清除作用,其中对·OH自由基的清除活力最好,在50 g/L时清除率高达93.94%。该研究利用海参肠道菌发酵海参下脚料来获得具有抗氧化活性的多肽,提高了下脚料的利用率及其经济价值。

A protease-producing bacterium from sea cucumber intestinal tract was isolated and identified.Through morphological,physiological,biochemical characterization and 16S rDNA sequence homology analysis,the isolated strain was identified as Thalassobacillus sp.QDHF-1.Sea cucumber intestine waste was fermented by strain QDHF-1,and the fermentation conditions were optimized and the antioxidant activities of produced peptides were determined.The optimal fermentation condition to produce peptides was 6%inoculum,20%raw materials and 36 h fermentation.The polypeptides could scavenge·OH,DPPH·,and O2^-·,and the highest scavenging rate of 93.94%was obtained on·OH using 50 g/L polypeptides.The results indicate the potential applications of strain QDHF-1 in sea cucumber offal fermentation to produce bioactive peptides.