细胞转化液γ-氨基丁酸的精制

Purification of Gamma-Aminobutyric Acid from the Supernatant after S.salivarius subsp.thermophilus Y-2 Transformation Reaction

对Streptococcus salivarius subsp.thermophilus Y-2细胞转化液GABA的纯化进行探讨,通过等电点沉淀和732强酸阳离子交换树脂处理。结果表明:GABA的总回收率达到84.13%;纯化的GABA的外观为白色粉末状固体,GABA含量(97.81±0.67)%,灰分(0.449±0.002)%,干燥质量损失率(1.79±0.06)%,铅、砷和汞的含量分别为(0.4093±0.0001)、(0.0511±0.0001)、(0.0950±0.0000)mg/kg,纯化的GABA质量符合食品添加剂标准。该方法可高效纯化细胞转化液中的GABA。

The concentrated supernatant after S.salivarius subsp.thermophilus Y-2 transformation reaction rich in gamma-aminobutyric acid（GABA）was adjusted to pH 3.22 for precipitate L-Glu,followed by injection into 732 type strong acidic cation exchange resin column and elution with 0.15 mol/L NH3·H2O.After freeze-drying,GABA was obtained as a white solid powder,with 84.13%recovery.The powder contained（97.81±0.67）%of GABA,（0.449±0.002）%of ash,and exhibited a dry weight loss of（1.79±0.06）%,and the contents of Pb,As and Hg in it were（0.4093±0.0001）,（0.0511±0.0001）mg/kg and（0.0950± 0.0000）mg/kg,respectively.Moreover,its quality was in accordance with relevant food additive standards.Thus,the purifica-tion strategy is highly efficient.