Bioprospecção de leveduras autóctones de frutos amazônicos potencialmente produtoras de enzimas aplicáveis na área de alimentos

Abstract

The Amazonian biome, consists of a large biodiversity. However, there are few studies with the yeast community associated with Amazonian fruits. Thus, this study aimed to know the fungal community present in pupunha (Bactris gasipaes) and Tucuman (Astrocaryum vulgare) during spontaneous fermentation, besides bioprospecting indigenous yeasts as to their ability to produce enzymes of industrial interest. Spontaneous fermentation was carried out over 15 days at 30 °C. The reducing sugars present it was stabilized, leading to an increase in the fruits' pH, reaching values of 7.66 and 6.74, in the titratable acidity of 1.91 and 1.63% lactic acid for pupunha and tucuman, respectively. Yeast diversity in fruit in spontaneous fermentation, it was performed through large-scale DNA sequencing of the ITS region where, 7 species of yeast have identified in the pupunha fruit, the species Galactomyces reessii was more abundant. In tucuman, 11 species have identified, but the species Meyerozyma carpophila was the most prevalent. It was also performed counting, isolation and morphological characterization of the colonies, the population of yeasts in the fruits reached 7.61 and 8.51 log CFU/g, being isolated 162 yeasts in pupunha and 149 in tucuman. The 311 isolates were subjected to qualitative plate tests to evaluate the production of enzymes, among them all produced invertase, 88 lipase and one isolate produced pectinase. The enzyme producing isolates were evaluated for the quantitative production of enzymes in submerged culture. Fourteen yeasts produced invertase, of which TCL30.3 (0.043 U/mL), PPL15.1 (0.31 U/mL) and PPL46 (0.31 U/mL) isolates showed higher activity. Six isolates produced lipase, highlighting the isolates TCL36.1, TCL33.1 and TCL25.5 with 0.081, 0.058 and 0.057 U/mL, respectively, as the best producers. The hydrolysis of babassu coconut oil were tested with 6 isolates, TCL52.1 presented the highest percentage of 23.53%. Fourteen isolates were submitted to the sucrose hydrolysis test, with PPL15.1 (41.34%) and TCL30.3 (50.47%) isolates with higher percentages of sucrose conversion. Fourteen isolates were submitted to the sucrose hydrolysis test, with PPL15.1 (41.34%) and TCL30.3 (50.47%) isolates with higher percentages of sucrose conversion.