Cereals as sources of lysine in the reformulation of meat products. Evaluation using a biosensor

• Published in: Biosensors and bioelectronics. X Vol. 23; p. 100592
• Main Authors: Alvarez Cañarte, Erika, Vergara Velez, Guilber, Intriago Flor, Frank Guillermo, Pérez Vega, Efrain, Falconi Vèlez, Miguel Andrès, Noriega Verdugo, Delia, García García, Génesis Pamela, Díaz Alarcón, Livis Sharith, Anchundia Loor, Andrés Miguel, Jadán-Piedra, Carlos, Jadán Piedra, Felipe
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.05.2025; Elsevier
• Subjects: low environmental impact; Lysine alpha oxidase; Malnutrition; Meat products; Sensor; Lysine alpha oxidase; Malnutrition; low environmental impact; Meat products; Sensor
• ISSN: 2590-1370; 2590-1370
• DOI: 10.1016/j.biosx.2025.100592

The energy and protein requirements of the population must be met, and the use of new analytical methods for rapid, low-cost detection of essential elements like lysine in reformulated foods is crucial. In this context, conditions were evaluated to develop a biosensor with lysine alpha oxidase (LOx), which showed high affinity for lysine with a KM of 0.32 mM. Different concentrations of cereals and legumes (70-30; 55-45; 85-15; quinoa-Lablab Purpureus; pole beans-Lablab Purpureus; and rye-Lablab Purpureus) were incorporated into meat sausages to enrich lysine, achieving a significant increase in lysine concentration (up to 75%) when 15% quinoa was substituted. The potentiometric signal, related to oxygen consumption during lysine oxidation, was detected at 15 s using a voltage of −600 mV. The biosensor, coupled with the immobilized enzyme, allowed the use of low volumes. A positive relationship was found between oxygen consumption (mg O2/L∗s-1) and lysine concentration in the range of 0.01–0.2 mM, with an R2 of 0.9964. The immobilized enzyme-based sensor demonstrated good sensitivity (0.01 mM) and the membrane could be reused up to 18 times, maintaining 92% of its initial activity after 70 days. The biosensor method showed minimal residue formation and had a strong correlation with high-performance liquid chromatography (HPLC) results, validating its accuracy. •The detection of lysine was specific in samples containing several amino acids.•The signal of oxygen consumption was obtained at 15 s.•A good correlation was obtained between the sensor and the HPLC methodology.•The sensitivity of the method improved when using the membrane immobilized.