Identification, Classification and Screening for γ-Amino-butyric Acid Production in Lactic Acid Bacteria from Cambodian Fermented Foods

• Main Authors: Dalin Ly, Sigrid Mayrhofer, I. B. Agung Yogeswara, Thu-Ha Nguyen, Konrad J. Domig
• Format: Article
• Language: English
• Published: MDPI AG 2019-11-01
• Series: Biomolecules
• Subjects: lactic acid bacteria; fermented foods; 16s rdna sequencing; maldi-tof ms; (gtg)₅ rep-pcr fingerprinting; gaba; cambodia
• Online Access: https://www.mdpi.com/2218-273X/9/12/768

Screening for various types of lactic acid bacteria (LAB) that form the biological agent &#947;-amino-butyric acid (GABA) is important to produce different kinds of GABA-containing fermented foods. So far, no GABA-producing LAB have been reported from Cambodian fermented foods. Most small-scale fermentations and even some industrial processes in this country still rely on indigenous LAB. The application of GABA-producing autochthonous starters would allow the production of Cambodian fermented foods with an additional nutritional value that meet the population&#8217;s dietary habits and that are also more attractive for the international food market. Matrix-assisted laser desorption/ionizing time-of-flight mass spectrometry (MALDI-TOF MS) and partial 16S rDNA sequencing were used to identify 68 LAB isolates from Cambodian fermented foods. These isolates were classified and grouped with (GTG)₅ rep-PCR, resulting in 50 strains. Subsequently, all strains were investigated for their ability to produce GABA by thin layer chromatography. GABA-positive strains were further analyzed by the GABase assay. Of the six GABA-positive LAB strains&#8212;one <i>Lactobacillus futsaii</i>, two <i>Lactobacillus namurensis</i>, and three <i>Lactobacillus plantarum</i> strains&#8212;two <i>Lactobacillus plantarum</i> strains produced high amounts of GABA (20.34 mM, 16.47 mM). These strains should be further investigated for their potential application as GABA-producing starter cultures in the food applications.