Development and Evaluation of a Low-Cost Triglyceride Quantification Enzymatic Biosensor Using an Arduino-Based Microfluidic System.

Overweight and obesity promote diabetes and heart disease onset. Triglycerides are key biomarkers for cardiovascular disease, strokes, and other health issues. Scientists have devised methods and instruments for the detection of these molecules in liquid samples. In this study, an enzymatic biosensor was developed using an Arduino-based microfluidic platform, wherein a lipolytic enzyme was immobilized on an ethylene-vinyl acetate polymer through physical adsorption. This low-cost optical biosensor employed a spectrophotometric transducer and was assessed in liquid samples to indirectly detect triglycerides and fatty acids using p-nitrophenol as an indicator. The average triglyceride level detected in the conducted experiments was 47.727 mg/dL. The biosensor exhibited a percentage of recovery of 81.12% and a variation coefficient of 0.791%. Furthermore, the biosensor demonstrated the ability to detect triglyceride levels without the need for sample dilution, ranging from 7.6741 mg/dL to 58.835 mg/dL. This study successfully developed an efficient and affordable enzymatic biosensor prototype for triglyceride and fatty acid detection. The lipolytic enzyme immobilization on the polymer substrate provided a stable and reproducible detection system, rendering this biosensor an exciting option for the detection of these molecules.

Antibiotic resistance and tolerance to simulated gastrointestinal conditions of eight hemolytic Bacillus pumilus isolated from pulque, a traditional Mexican beverage.

Traditional fermented sap beverages from two provinces of Mexico were studied for the isolation of pathogenic bacteria from these beverages. Eight strains of hemolytic Gram positive bacteria, identified as Bacillus pumilus (B. pumilus), were isolated. They showed different antibiotic resistance profiles and tolerances to the simulated gastrointestinal conditions. All the B. pumilus isolated were resistant to at least one antibiotic tested. Regarding the simulated gastrointestinal conditions, strains S1 and S3 were able to tolerate all the conditions. Hemolytic activity has been associated with a health risk and is often considered as a virulence determinant associated with pathogenicity. Therefore, the hemolytic activity along with the ability to tolerate gastrointestinal conditions and the resistance to antibiotics exhibited by B. pumilus strains S1 and S3 could be associated with a health risk for pulque consumers.