1774
Lactobacillus brevis YM 3-30, a γ-aminobutyric acid producing bacteria, increases antioxidant concentration and reduces biogenic amines
This study was conducted to determine the effects of Lactobacillus brevis YM 3-30, a γ-amino butyric acid (GABA) producing bacteria (GPB), on in vitro rumen fermentation. Also, evaluation of biogenic amines and antioxidant concentration were analyzed. Ruminal samples were collected from ruminally cannulated Hanwoo cattle and soybean meal was used as substrate at 1g dry matter (DM) per 100ml buffered rumen fluid. Different inclusion rates of GABA produced by GPB, L. brevis YM 3-30, were investigated using in vitro rumen fermentation. The following treatments were: 2 g/kg and 5 g/kg fresh GABA, 2 g/kg and 5 g/kg autoclaved GABA, and non addition of GABA and, hereafter referred to as treatments 2, 3, 4, 5, and 1, respectively. Fresh culture of GPB was added in treatments 2 and 3 while autoclaved GPB for treatments 4 and 5. The GPB was autoclaved at 121°C for 15 min prior to inclusion into the fermentation bottles. Addition of GABA produced by GPB had no significant effect on pH and total gas production, but did increase (P<0.05) the ammonia nitrogen (NH3-N) and reduce (P<0.05) the total biogenic amines (TBA). Treatment groups containing GPB-produced GABA (T2 and T3) having the lowest (P<0.05) volumes of TBA with 10.62 mM to 11.21 mM. Additionally, histamine was produced in the highest levels in T1 at 15.99 mM. Acetate, propionate, and butyrate concentrations and acetate:propionate (A:P) ratio did not differ significantly among treatments. The volume of production of SOD and GSH-Px were significantly highest in treatments added with 5 g/kg GABA (T3) after 24 h of incubation with 76.60 U/ml and 38.51 U/ml, respectively. The addition of GABA produced by GPB improves in vitro fermentation by reducing biogenic amines production while increasing antioxidant activity and NH3-N production.
Keywords: Antioxidant, Biogenic amines, γ-amino butyric acid