ABSTRACT
Sugar and artificial sweeteners are additives in packaged food and beverage products that are widely used, where excessive sugar consumption can cause an increase in various diseases. Detection and classification of natural sugars sucrose, fructose, glucose, and artificial sweetener aspartame are needed to determine the effects of consuming these sweeteners. This study uses an amperometric biosensor integrated biochip-D, which uses Saccharomyces cerevisiae as a bioreceptor through cellular metabolic respiration activity expressed in dissolved oxygen (DO) levels. The variations of sweetener concentration used were in the range of 50 mM to 250 mM. The measurement results showed that the higher the concentration of sugar and artificial sweeteners, the lower DO levels would be measured. It was due to the yeast cell respiration in consuming oxygen (O2) and producing carbon dioxide (CO2), where the decrease in DO levels of sucrose was 14.24%, fructose was 18.02%, glucose was 16.59%, and aspartame was 20.45% at a concentration of 250 mM. The measurement data was clustered and classified using principal component analysis (PCA), which resulted in data variance percentages of 92.80% and 89.40% for the two main components. In the application studies of the biosensor, sensitive determination of sugar in the beverage samples was investigated. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05625-8.
ABSTRACT
Environmental problems including water and air pollution, over fertilization, insufficient wastewater treatment and even ecological disaster are receiving greater attention in the technical and scientific area. In this paper, a method for water quality monitoring using living green algae (Chlorella Kessleri) with the help of the intelligent mobile lab (IMOLA) is presented. This measurement used two IMOLA systems for measurement and reference simultaneously to verify changes due to pollution inside the measurement system. The IMOLA includes light emitting diodes to stimulate photosynthesis of the living algae immobilized on a biochip containing a dissolved oxygen microsensor. A fluid system is used to transport algae culture medium in a stop and go mode; 600s ON, 300s OFF, while the oxygen concentration of the water probe is measured. When the pump stops, the increase in dissolved oxygen concentration due to photosynthesis is detected. In case of a pollutant being transported toward the algae, this can be detected by monitoring the photosynthetic activity. Monitoring pollution is shown by adding emulsion of 0,5mL of Indonesian crude palm oil and 10mL algae medium to the water probe in the biosensor.
