Synthesis of γ-Aminobutyric Acid by Lactic Acid Bacteria Isolated from a Variety of Italian Cheeses

Abstract

The concentrations of ␥-aminobutyric acid (GABA) in 22 Italian cheese varieties that differ in several technological traits markedly varied from 0.26 to 391 mg kg ؊1 . Presumptive lactic acid bacteria were isolated from each cheese variety (total of 440 isolates) and screened for the capacity to synthesize GABA. Only 61 isolates showed this activity and were identified by partial sequencing of the 16S rRNA gene. Twelve species were found. Lactobacillus paracasei PF6, Lactobacillus delbrueckii subsp. bulgaricus PR1, Lactococcus lactis PU1, Lactobacillus plantarum C48, and Lactobacillus brevis PM17 were the best GABA-producing strains during fermentation of reconstituted skimmed milk. Except for L. plantarum C48, all these strains were isolated from cheeses with the highest concentrations of GABA. A core fragment of glutamate decarboxylase (GAD) DNA was isolated from L. paracasei PF6, L. delbrueckii subsp. bulgaricus PR1, L. lactis PU1, and L. plantarum C48 by using primers based on two highly conserved regions of GAD. A PCR product of ca. 540 bp was found for all the strains. The amino acid sequences deduced from nucleotide sequence analysis showed 98, 99, 90, and 85% identity to GadB of L. plantarum WCFS1 for L. paracasei PF6, L. delbrueckii subsp. bulgaricus PR1, L. lactis PU1, and L. plantarum C48, respectively. Except for L. lactis PU1, the three lactobacillus strains survived and synthesized GABA under simulated gastrointestinal conditions. The findings of this study provide a potential basis for exploiting selected cheese-related lactobacilli to develop health-promoting dairy products enriched in GABA.

Enhancement of γ-Amminobutyric Acid Production by Co-Culturing of Two Lactobacilli Strains

“…GABA is present in small quantities in many plant sources, vegetables, for example spinach, potatoes, cabbage asparagus (broccoli), tomatoes, fruits, for example apples, grapes, in cereals, for example barley, maize. The increased amount is found mainly in fermented products, especially fermented dairy products, soy sauce (Yamakoshi et al, 2007), cheeses (Siragusa et al, 2007) and so on. Natural addition of GABA is in high demand over the addition of chemical nutrient GABA since consumers prefer naturally occurring substances and the fermentation helps to reduce the cost of the foods due to the omission of chemical addition of GABA and also provides attractive foods with better taste and at the same time replaces the chemical GABA by natural GABA .…”

Screening and kinetics of glutaminase and glutamate decarboxylase producing lactic acid bacteria from fermented Thai foods

“…The GAD produced by L. brevis was biochemically well characterized previously (Hiraga et al, 2008). L. brevis PM17 was also reported for the GABA-producing ability (Siragusa et al, 2007).…”

“…delbrueckii subsp. bulgaricus (Siragusa et al, 2007), Bifidobacterium dentium (Barrett et al, 2012), and Streptococcus salivarius subsp. thermophilus (Yang et al, 2008b) are reported to produce GAD with different efficiency and optimum conditions.…”

“…L. lactis (Lu et al, 2009;Siragusa et al, 2007), Lb. buchneri (Cho et al, 2007;Park & Oh, 2006), Lb.…”

A survey of the main technology, biochemical and microbiological features influencing the concentration of biogenic amines of twenty Apulian and Sicilian (Southern Italy) cheeses

“…Concentration of individual FAAs in cheese was determined as described by Siragusa et al (2007), with few modifications. In detail, 30 g of cheese was grated and homogenised (5 min treatment) with 90 mL of 50 mmol L À1 phosphate buffer, pH 7.0, in a blender.…”