Characterization of waste cell biomass derived glutamate decarboxylase for in vitro γ-aminobutyric acid production and value-addition. (October 2021)

• Record Type: Journal Article
• Authors: Wu, Chien-Hui; Dong, Cheng-Di; Kumar Patel, Anil; Rani Singhania, Reeta; Yang, Ming-Jie; Guo, Huei-Rong; Kuo, Jen-Min
• Is Part Of: Bioresource technology. Volume 337(2021)
• Publication Date: 2021-10
• Subjects: γ-aminobutyric acid -- Lactobacillus brevis -- Glutamate decarboxylase -- Priacanthus macracanthus; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2021.125423
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: L. brevis RK03 post-fermentative biomass utilized for GAD extraction. 52 W ultrasonic output was best for intracellular crude GAD extraction. Molecular weight of the purified GAD was determined to be ~53 kDa. Km value of GAD for L-glutamic acid was calculated about 7.65 mM. Purified GAD can be exploited for cheaper industrial production of GABA. Abstract: Waste biomass of Lactobacillus brevis obtained from in vivo γ-aminobutyric acid (GABA) production was used for value-addition. This study aims to extract glutamate decarboxylase (GAD) and characterize it for in vitro GABA production. Extracted GAD showed an excellent activity for in vitro GABA production. 52 W ultrasonic output was best in crude GAD extraction which was purified by Q HP anion-exchange column followed by Superdex-200 colloid separation column. The molecular weight of the purified GAD was determined to be ~53 kDa, and the Km value for L-glutamic acid was calculated ~7.65 mM. Pyridoxal 5′-phosphate (PLP) acted as the best cofactor for GAD. Optimum temperature and PLP dosing were deferring for crude and purified enzyme forms which respectively exhibited at 45°C, 55°C, 200 µmol and 20 µmol whereas optimum pH was the same at 4.5. GAD finds applications in food industries hence its detailed characterization would be promising for commercial exploitations.