Abstract

MILLAN-CHIU, Blanca E. et al. Shock wave-assisted extraction of chitin from Aspergillus niger: physicochemical and electrical characterization. Mundo nano [online]. 2023, vol.16, n.31, 69796.  Epub Sep 04, 2023. ISSN 2448-5691.  https://doi.org/10.22201/ceiich.24485691e.2023.31.69796.

Chitin is a linear polysaccharide produced by animal and fungal species. One of its sources is the fungus Aspergillus niger, which is culturable in industrial bioreactors. Chitin is a neutral biopolymer that modifies the electrical properties of composite materials. These are useful features in some electronic devices. This study aimed to carry out physicochemical characterizations of chitin films obtained from the above-mentioned fungus, using a chemical method enhanced with exposure to heat and shock waves, and to determine their electrical resistivity at high voltages (between 10 and 20 kV). Shock waves were used in this study because they are known to induce pores into cells and could promote alkali entry into the hypha, allowing better removal of residual cellular components. Chitin was neutralized, dried, and films were produced. Residual protein values were quantified by bicinchoninic acid assay (BCA). The films obtained had low amounts of protein. The characterization of the specific morphotype extracted was done by FTIR and XRD. An especially designed circuit revealed significant variations of the resistivity as the voltage was varied. This behavior is typical of a non-linear varistor and, to the best of our knowledge, has not been reported for chitin.

Keywords : Aspergillus niger; shock waves; chitin films; electrical resistivity.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )