Crab shells contain quite a lot of chemical compounds, including 30–
40% protein, 30–50% minerals (CaCO3) and 20-30% chitin. The chitin can be
further deacetylated to produce chitosan. By combining chitosan with galactose
can increase the antioxidant activity of chitosan. The purpose of this study was
to vary the ratio of chitosan:galactose to determine the best concentration.
The sample in this study came from the city of Rembang, Central Java.
Sampling refers to the method of Younes & Rinaudo, 2015. Furthermore, the
functional groups were carried out using an FTIR spectrophotometer and the
physical characteristics of each formula. The antioxidant activity test was
measured using the DPPH method. The materials used include galactose,
methanol pro analysis, and DPPH.
The results of the study based on DPPH SA (%) of each formula
obtained the best results at a ratio of 2:1 of 64.58%. This proves that the
antioxidant activity of pure chitosan resulted in lower DPPH SA (%) than
chitosan which resulted in the formation of complexes. With a lower
concentration of galactose can produce more DPPH SA (%).
Key words: Complex chitosan, DPPH, chitosan galactose ratio