Preparo de filme repelente biodegradável a partir de nanocelulose obtida do resíduo biológico da Kombucha, amido e óleo essencial de citronela

Abstract

Faced with a scenario of increasing records of probable cases of diseases transmitted by insects, alternative repellents have been sought as a form of prevention and, among these, are repellent patches using citronella essential oil as the repellent substance. These patches are produced with non-renewable plastic material and made available on the national market through imports. Considering the above, the objective was to prepare a biodegradable repellent film from a renewable source such as bacterial cellulose obtained through the fermentation of Kombucha, added to starch and citronella essential oil, known for its repellent properties. To this end, an initial membrane was obtained and then purified to produce bacterial cellulose and isolate nanofibers, which was later used as a stabilizing agent in the preparation of an emulsion containing citronella oil. Cassava starch films were prepared from this emulsion to obtain a material with repellent activity. These films were characterized in terms of their morphology using microscopy techniques such as SEM and AFM, their structure via FTIR and XRD, thermal and mechanical properties via TGA, and uniaxial tensile testing. It was observed that the process of purification by alkaline means of the fibers obtained after fermentation can change their chemical composition so that the percentage of α-cellulose can reach up to 90% of the fiber composition. Crystallinity is also directly affected due to the purification treatment. The biodegradation properties of these films are under evaluation over a current period of 17 weeks, and previous results have shown the influence of citronella oil on the microbiological activity of the soil, as well as on the mechanical properties of the films according to the percentage of citronella oil used. in the production of films that use cassava starch as a matrix.