The effect of fermented buckwheat on producing L-carnitine and Gamma-aminobutyric acid enriched designer eggs

Background: The potential of fermented buckwheat as feed additives was studied to increase L-carnitine and gamma-aminobutyric acid (GABA) in designer eggs. Buckwheat contains high levels of lysine, methionine, and glutamate, which are precursors for the synthesis of L-carnitine and GABA. Rhizopus oligosporus was used for the fermentation of buckwheat to produce L-carnitine and GABA that exert positive effects like enhanced metabolism, antioxidant activities, immunity, and blood pressure control.  Objective: To study the fermentation of buckwheat using Rhizopus oligoporus ( R. oligoporus ) and to analyze the extract regarding the amounts of L-carnitine and GABA. Then, to be used as a complex additive in poultry feed to determine whether L-carnitine and GABA can be transferred into the eggs.  Methods: For this purpose, we developed a novel, simplified detection method for both L-carnitine and GABA in eggs using LC/MS/MS with common solvents, simple aqueous extractions, and acetonitrile deproteinization. Microbial strain was identified and fermented buckwheat was prepared. Various components were characterized by using HPLC-UV, LC/MS or LC/MS/MS. The analyses conditions were used as the following: Fermented buckwheat sample was prepared at 100 mg mL-1 with dilution by acetonitrile and filtered with a 0.2 µm membrane syringe filter (Sartorius AG, Germany), then 1 µL of the sample was injected into the LC/MS (Waters, MA, USA). The system used was Waters Acquity H-class with Waters QDa detector (Waters, MA. USA) and Waters Acquity UPLC Beh Hilic 1.7 µm, 2.1 x 100 mm column. Solvent A was 15 mM ammonium formate with 0.1% (v/v) formic acid and solvent B was acetonitrile with 0.1% (v/v) formic acid. The sample and column temperatures were 10°C and 40°C, respectively. A gradient from 0 to 3 min was applied for 10% of solvent A, which increased to 30% for a gradient from 3.1 to 5 min. From 5.1 to 6 min, 60% of solvent A was used, followed by an equilibrium step for 4 min. Electrospray ionization (ESI) positive and selective ion recording (SIR) mode (162 m/z for L-carnitine and 104 m/z for GABA) were used. The feeding experiment was conducted with Hy-Line brown hens and the weights of the shell, yolk, and albumen were measured. Results: A novel analytical method for simultaneously detecting L-carnitine and GABA was developed using LC/MS and LC/MS/MS. The fermented buckwheat extract contained 4 and 34 fold-increased L-carnitine and GABA, respectively, than normal buckwheat. Compared to the control, the fermented buckwheat extract-fed group showed enriched L-carnitine (13.6%) and GABA (8.4%) in the yolk. However, only L-carnitine was significantly different (p<0.05). Egg production (9.4%), albumen weight (2.1%), and shell weight (5.8%) were significantly increased (p<0.05). There was no significant difference in yolk weight, total cholesterol (1.9%) and triglyceride (4.9%) in the yolk was lowered (p<0.05).  Conclusion: Fermented buckwheat as an additive has the potential to produce L-carnitine and GABA enriched designer eggs with enhanced nutrition and homeostasis. The L-carnitine and GABA enriched designer eggs pose significance to be utilized in superfood production and supplement industries. Keywords:  Buckwheat, Fermentation,  Rhizopus oligosporus , L-carnitine, GABA, Designer Egg How to cite this abstract:  Kim D., Nguyen T.T.H., Park N., Kim N.M.; FFC’s 22 nd International Conference; Boston, MA, USA; Organized by FFC and BIDMC/ Harvard Medical School Teaching Hospital; Volume 1; Supplement 1: 192-194