Influencia del quitosano obtenido desde exoesqueletos del camarón (Litopenaeus vannamei) sobre la germinación de cebada (Hordeum vulgare)

Abstract

The aim of this study consisted of obtaining chitosan from chitin from the shrimp exoskeleton (Litopenaeus vannamei) to determine the influence of chitosan on the germination of barley (Hordeum vulgare) grains. Chitosan was obtained from quitine by deacetylating 1 gram of quitine with 20 ml of 50 % NaOH at 100 degrees Celsius at three hydrolysis times (1, 3 and 5 hours), equivalent to three experimental treatments respectively (T1, T2 and T3). The chitosans obtained were subjected to characterization tests: solubility and gelling, infrared spectroscopy (IR), degree of deacetylation (GDA) and molecular weight (Mv), on the basis of which the best chitosan was selected and used in the barley grain germination process. After characterizing the chitosans of the three treatments, it was determined that the best chitosan corresponds to that of treatment T3 (5 hours of hydrolysis), which gelled acceptably and had a good solubility in lactic acid (1 %), a degree of deacetylation of 87.13 %, and a molecular weight of 4.67E+06 g/mol. The optimum concentration of the obtained chitosan was 1 % in lactic acid (1 %), based on the fact that the solubility of chitosan in lactic acid was 98.22 %. For the germination of the barley grains, they were treated with an optimal chitosan solution and monitored for 138 hours carrying out a follow up according to three parameters: germination with radicles larger than 0.5 cm, germination with radicles smaller than 0.5 cm and total germination. The result of the monitoring allowed establishing that chitosan in lactic acid does not significantly accelerate germination by 6.66 % as compared to the control corresponding to lactic acid (1 %).