Produção de invertase de bacillus tequilensis isolada do fruto pupunha: propriedades bioquímicas e produção de fruto-oligossacarídeos

Abstract

Invertases (E.C. 3.2.1.26) are enzymes that have the ability to produce inverted sugar by cleaving the α-1, 4-glycosidic bond between D-glucose and D-fructose. They can be found in various living beings, such as plants, animals and microorganisms, with microbial production being the fastest and most advantageous. Bacteria have great technological potential for the production of invertases through liquid state cultivation (Smf), a technique in which 90% of microbial enzymes for industrial use are obtained. The Amazon is the largest biome on the planet and its fruits contain an extensive variety of autochthonous microorganisms with biotechnological potential, such as peach palm fruit. Therefore, the objective of this work was to produce bacterial invertase from a strain of Bacillus tequilensis PP6 isolated from peach palm fruit and obtain the best composition of culture medium for this production, testing six different media, the medium consisting of (NH₄)₂SO₄; 0.5, KH₂PO₄; 0.1 MgSO₄; 0.1 CaCl2; 0.01 and NaCl; 10 provided the highest enzymatic activity (3.60 U/mL). Also, we sought to analyze the best carbon source, varying crops with P.A sucrose, brown sugar and demerara sugar at concentrations of 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 % (m/v). Demerara sugar, at a concentration of 3% (m/v) showed the highest value of enzymatic activity (5.53 U/mL). The biochemical characterization of the enzyme showed that the best pH and temperature values of the reaction medium were equal to 5.0 and 50 °C, respectively. Regarding stability in relation to pH, the enzyme was stable at all pHs, analyzing the influence of ions on the enzymatic activity, it was found that the presence of iron increased the activity of the enzyme by 157.55%, while the presence of sodium increased the activity of the enzyme by 22.85% in relation to its initial activity. It was also possible to evaluate the transfructosylation activity of the enzyme, with sucrose concentrations of 20 and 30% (m/v) being the best for the production of transfructosylated fructose, with values of 14.72 g/L and 14.60 g/ L, respectively, for 90 minutes in fact.