Potencial de aplicação de peptídeos bioativos, obtidos a partir de Tenebrio molitor, para aplicação na nutrição de peixes: Propriedades físico-químicas, capacidade antioxidante e atividade antimicrobiana

Abstract

Aquaculture stands out for producing good quality protein in more sustainable systems, and bringing food security. However, the intensification of production, combined with the lack of good management practices, can generate stress for the animals and thus facilitate the entry of diseases and parasites. Strategies have been adopted in order to guarantee increased production and maintain the health of animals, such as the use of antibiotics, which have been wrongly applied due to their negative impacts. Obtaining bioactive peptides from insects is being highlighted in research, which has shown antioxidant, antibacterial activity and improvements in the health status of fish. For this reason, Tenebrio molitor is a potential substrate for obtaining bioactive peptides, which can be included in the diet of aquatic organisms as a substitute for antibiotics, acting in the fight against bacterial infections, pathogens and strengthening the immune system of animals. The objective of this work was to standardize a methodology for obtaining bioactive peptides from T. molitor for use in fish nutrition. Larvae produced at Unipampa Animal Biodiversity Laboratory were partially dried (55°/48 h) to obtain flour, before lipid extraction with hexane. The defatted tenebrium flour was pre-incubated with distilled water at 55oC for 30 minutes. After pre-incubation, the following assays were evaluated using Alcalase enzyme: 1) 20 L enzyme per 50 mL, for 3 h; 2) 40 L enzyme per 50 mL, for 3 h; 3) 20 L enzyme per 50 mL, for 4 h; 4) 40 L enzyme per 50 mL, for 4 h; 5) 20 L enzyme per 50 mL, for 8 h; 6) 40 L enzyme per 50 mL, for 8 h; All tests were performed at 55°C and the pH adjusted to 7.0 with NaOH (0.1N). After hydrolysis, the enzyme was inactivated and the solution centrifuged. The degree of hydrolysis (GH) was higher in assays 5 (8.14±0.04%) and 6 (8.38±0.08%) where longer hydrolysis duration was applied. The glycogen content was higher for the bioactive peptides compared to the in natura sample. The antioxidant capacity was 12 to 14% lower in trials 6 and 5. Bioactive peptides were not effective in preventing microbial growth. The peptides produced from T. molitor have great potential for inclusion in fish diets, and the hydrolysis methodology can be optimized.