Optimization and comparison of ℽ-aminobutyric acid (GABA) production by LAB in soymilk using RSM and ANN models

Abstract

Background ℽ-Aminobutyric acid (GABA) is a non-proteinaceous amino acid. In the mammalian nervous system, GABA functions as an inhibitory neurotransmitter. The present study focused on screening and optimization of ℽ-aminobutyric acid (GABA) yield by lactic acid bacteria by using soymilk as basal media. Lactobacillus fermentum (Lb. fermentum) was isolated from sourdough. The qualitative confirmation of GABA production by Lb. fermentum was observed by detecting colored spots on thin layer chromatography plate (TLC) and comparing it with standard GABA spot. The GABA from bacteria is confirmed by its molecular mass using mass spectrophotometry analysis (MS analysis). Single variable experiments were conducted for various physical and nutritional parameters, and determined the GABA content produced from Lb. fermentum, viable bacterial count, and pH of the fermented soymilk medium. Experimental data were authenticated by using response surface method (RSM) and artificial neural network (ANN) model. Results The results demonstrated that through single variable experiments, the yield of GABA and the viable bacterial cells increased in soymilk containing one percent of glucose, monosodium glutamate (MSG), and inoculum volume incubated at 37 °C, 48 h at pH 5. According to RSM results, the interaction of the highest concentration of MSG (1.5%) and mid glucose concentration (1.156%) yielded maximum GABA (5.54 g/L). The experimental data were in good agreement with two optimization models. The RSM models showed less error percentage than that of the ANN model. Conclusion This study indicates that soymilk is the best basal substrate for GABA production and growth of Lb. fermentum compared to synthetic media. Lb. fermentum can be explored further by food and pharmaceutical industries for the development of functional foods and therapeutic purposes.

Probiotic Properties and Optimization of Gamma-Aminobutyric Acid Production by Lactiplantibacillus plantarum FBT215

“…Therefore, RSM with the CCD model was assessed for optimizing GABA production in an L. fermentum isolate. Three variables were analyzed, i.e., glucose concentration, MSG concentration, and incubation time [38]. GABA production by Lactobacillus sp.…”

“…Three variables were analyzed, i.e. , glucose concentration, MSG concentration, and incubation time [ 38 ]. GABA production by Lactobacillus sp.…”

“…nov. was obtained from pickle [ 11 ]. Optimizing microbial GABA production is indispensable for manufacturing commercial GABA products [ 7 , 12 , 13 ].…”

Biosynthesis of gamma-aminobutyric acid by Lactiplantibacillus plantarum K16 as an alternative to revalue agri-food by-products

“…However, a higher inoculum (8 log CFU/ mL) increased the microbial cell growth to 9.2 log CFU/mL but yielded 101 mg/L of GABA. Rayavarapu et al 28 showed that the highest amount of GABA produced by L. fermentum was 3.79 g/L and the microbial cell growth was 5.8 log CFU/mL using a 1% of inoculum. However, an increase of inoculum to 2% did not significantly change the GABA production yielding 3.71 g/L and a microbial cell growth of 6.4 log CUF/mL.…”

Characterisation of the probiotic potential of Lactiplantibacillus plantarum K16 and its ability to produce the postbiotic metabolite γ-aminobutyric acid

“…In this sense, several studies have reported that GABA production by L. plantarum strains could increase at the end of the exponential phase or near the stationary phase (Park et al 2021b). Likewise, Rayavarapu, Tallapragada, and Ms (2021) observed that during the first 24 h of incubation, LABs focused on cell multiplication, and the GABA yield was low but after 48 h the microorganisms reached the stationary phase and the amount of GABA produced was higher.…”