鳕鱼酶解液苦味肽的纯化鉴定

Purification and Identification of Bitter Peptides from Codfish Hydrolysate

本文利用DA201-C大孔树脂对鳕鱼肉碱性蛋白酶酶解液进行脱盐后,用SP Sephadex C-25阳离子交换层析和反相高效液相色谱等方法对鳕鱼肉酶解液进行分离纯化,最终得到了浓度较高的两种苦味肽。将得到的苦味肽采用液相色谱-飞行时间串联质谱(LC-TOF-MS/MS)技术对多肽结构进行鉴定,确定其氨基酸序列分别为:HWPWMK(His-Trp-Pro-Trp-Met-Lys)和AVVLII(Ala-ValVal-Leu-Ile-Ile)。同时本文采用感官评定与多肽Q值相结合的方法对苦味进行评价,通过氨基酸分析仪对苦味样品进行氨基酸组成的测定,得出具有苦味的C7和S9组分的Q值分别为6.03 k J/mol和6.79 k J/mol,通过感官评定得出其苦味强度为:9±0.8和8.2±1.6。鉴定得到的苦味肽S9purity和S10purity的Q值分别为:8.85 k J/mol和8.53 k J/mol,苦味强度为:9.4±0.8和8.9±0.9。本文从鳕鱼肉酶解液中分离纯化得到的苦味肽为苦味肽家族增添了新成员,为下一步的研究提供了原料和实验基础。

Alkaline protease hydrolysate was isolated from codfish muscle, desalinated using DA201-C macroporous resin, and purified using SP Sephadex C-25 ion-exchange chromatography and reversed-phase high-performance liquid chromatography（RP-HPLC）. The final product comprised of two bitter peptides at a relatively high concentration. Peptide structures were characterized by liquid chromatography/time-of-flight tandem mass spectrometry（LC-TOF-MS/MS）, while bitterness intensity was evaluated by a combination of sensory evaluation and Q value. Their amino acid sequences were determined using an amino acid analyzer as HWPWMK（His-Trp-Pro-Trp-Met-Lys） and AVVLII（Ala-Val-Val-Leu-Ile-Ile）. The amino acid composition of bitter fractions C7 and S9 was also analyzed; their Q values were determined as 6.03 and 6.79 k J/mol, while their bitterness intensities were determined by sensory evaluation as 9 ± 0.8 and 8.2 ± 1.6, respectively. Q values of the purified bitter peptides S9 purity and S10 purity were 8.85 k J/mol and 8.53 k J/mol, while their bitterness intensities were 9.4 ± 0.8 and 8.9 ± 0.9, respectively. The bitter peptides isolated and purified from the codfish hydrolysate in this study are new members of the bitter peptide family and provide data for further study.