Potencial biotecnológico de leveduras isoladas de jardim de fungos da formiga Atta robusta Borgmeier (Hymenoptera: Formicidae)

Abstract

Enzymes microbial are important catalysts, which have large industrial and biotechnological potential. The production of enzymes, especially amylases, proteases and cellulases is increasing, as these are used as biotechnological tools in various industrial sectors. Some species of yeast also have ability to survive in conditions with varying concentrations of compounds such as salt, pH and temperature, which favors their application in many industrial sectors as bleaching textile dyes and biofuels. The objective of this work was to study the production capacity of enzymes of industrial interest, as well as discoloration of yeasts isolated from fungus gardens robust Atta ant. This kind of cutting ant is endemic of restinga areas in the states of Rio de Janeiro and Espírito Santo, which are suffering strong anthropogenic action and having their seriously threatened habitat. In Chapter 1, the enzyme production by 78 yeast grown in media with 1% carbon source and protein was studied. After the growth was added dye to visualize the formation of halos of hydrolysis: lugol for amylase and cellulase for congo red; for the protease was observed transparent halo around the colony. For inulinase was analyzed growth in inulin and compared with the positive and negative controls. Also osmophilic tolerance tests were performed in media containing 50% glucose and medium with 10% NaCl, and tests for assimilation ethanol production amyloid compounds and thermotolerance at temperatures of 35, 37, 40, 42 and 45°C. As a result, 32% produced amylase, 5% produced the enzyme protease, cellulase produced 39% enzyme, 58% of the isolates are shown capable of producing the enzyme inulinase. For the osmophilic tolerance testing, it was considered moderate growth for the ethanol uptake isolates were able to grow only 9 isolates are extracellular amyloid producing compounds and 4 isolates grew in the 35 ° C temperature. In chapter 2, was performed destaining, industrial dyes tests, dye Orange G were used, Remazol Brilliant Blue, Remazol Brilliant Violet and Black Reactive 5 and realized phytotoxicity tests using lettuce seeds (Lactuca sativa) and calculating germination rate (GR %) and inhibition of root growth rate (IRGR). The H. heimii showed good decolorization within 24 hours for both dyes Remazol Brilliant Violet and for Reactive Black 5, reaching 94.5% and 97.3% discoloration rate, respectively, and for the dye Orange G, Remazol Brilliant Blue, discoloration rates were low, reaching a maximum of 25.8% and 42.1%, respectively. According to the results of TG and TICR of the phytotoxicity test, supernatants from both Remazol Brilliant Violet dyes and Reactive Black 5, in general, presented less toxic those original dyes. Isolated from ant fungus garden Atta robusta showed good potential for enzyme production and use in bleaching processes.