Effects of Alkaline and Acid Treatment to theYield and Quality of Chitosan Extracted from Absidia sp. dr

Abstract. Chitosan was extracted from 60-hour old biomass of A bsidia sp. dr that was subjected to different alkaline and acid treatment in the extraction protocol. In both alkaline and acid treatment, the temperature, incubation period and concentration of acid or alkaline significandy affects the production and quality of the chitosan produced (P 0.05). The type of acid used was also important in the production of chitosan. Quality analysis was performed to determine the degree of deacetylation, molecular weight and colour of chitosan. Usage of hydrochloric acid in the extraction of chitosan gave a significandy higher degree of deacetylation (DD) compared to acetic acid and formic acid. The average molecular weight of selected chitosan samples obtained ranged from 6.765 X 10^4 Da to 2 .757 X 10^5 Da. Employment of strong acid, high acid concentration and high temperature produced darker coloured chitosan whereas milder treatments gave lighter coloured chitosan.