Obtención de azucares totales a partir de la cáscara de arroz (oryza sativa) mediante la aplicación de corriente eléctrica alterna

Abstract

The rice husk that covers the grain of rice, represents approximately 20-33% of the husk which is wasted and is rather burned to occupy the large spaces inside the piladoras, it is a by-product that results from the composite milling industry by cellulose, hemicellulose and lignin, being mainly a source rich in silica. The objective of the present investigation was the obtaining of total sugars present in the rice husk variety Iniap-14 (Oryza sativa L) by applying alternating electric current (AC), being a food that is produced in greater quantity in the province of El Oro. The studies that were carried out were: conductivity by conductimetry, current by ammeter, pH by potentiometry and total sugars by means of the 3,5-dinitrosalisilic acid (DNS) method by means of a device called UV digital spectrophotometer, the electrolysis was done adding three different 1% salts which were: ferric chloride (FeCl₃), potassium chloride (KCl) and sodium citrate (Na₃C₆H₅O₇), a control of 4 days was taken at room temperature, taking sample every 12 hours, the type of chemical compound that gives greater conductivity to the medium with a time of 48 hours, where an experimental design was applied 2³ where the factors considered were chemical compounds and voltage. The results obtained in figure 10 showed that the total sugars gave as a result that among the three chemical compounds (ferric chloride, potassium chloride and sodium citrate) the highest gain was ferric chloride, which shows that said compound generates better effects of adsorption of sugars in the rice husk, observing that there is a significant difference in total sugars with the other salts, where it begins to have a trend behavior with values close to 8000mg / L, the same one that presented a favorable behavior for the passage of electricity obtaining better values of conductivity, helping to break the molecules present in the rice husk since it generates a better conductivity and a greater fluidity to the sample as well as better extraction of alkalinity pH, using lower values of current with the step Of the hours. In conclusion, the application of alternating current favors the hydrolysis of the rice husk, which is evidenced in the presence of reducing sugars in the hydrolyzed solution, due to the breakdown of the rice husk molecules. The addition of metal salts increased the conductivity in the solution and therefore the circulation of current, it was established that the electrolysis at 60 V with the ferric chloride salt compared to the other salts obtained a significant percentage of conversion of cellulose to total sugars , since at the end of the electrolysis time with ferric chloride at 12 o'clock a significant increase in sugars was noted, which indicates that the hydrolysis process is occurring in the lignocellulose biomass, noting the increase in the concentration of total sugars in the hydrolyzate, being the ferric chloride compound the best result since it presented a favorable behavior.