Abstract Ellagic acid (EA) is a phenolic biomolecule. For its biosynthesis, a source of ellagitannins is required, such as strawberries and yeasts, as precursors of the tannase and β-glucosidase enzymes responsible for hydrolysis of ellagitannins. Two experimental mixture designs were applied., varying the yeast concentration and the number of ellagitannins in the culture medium, evaluating the enzymatic activity and ellagic acid biosynthesis. Aiming to find the optimal compositions of the non-conventional yeasts assessed in the research to biosynthesize ellagic acid feasibly and efficiently using a response surface performing the statistical analysis in the StatGraphics® program for obtaining a higher yield and optimizing the ellagic acid synthesis process, the results indicate that the strains Candida parapsilosis ITM LB33 and Debaryomyces hansenii ISA 1510 have a positive effect on the synthesis of ellagic acid, since as its concentration increases in the mixture the concentration of ellagic acid in the medium also increases; on the other hand, the addition of Candida utilis ITM LB02 causes a negative effect, resulting in the compositions of 0.516876, 0.483124 and 2.58687E-9 respectively, for a treatment under the same conditions, an optimal value of ellagic acid production would be obtained. With an approximate value of 7.33036 mg/mL.

Abstract Non-conventional yeasts represent an alternative for microorganisms that are capable to produce the enzyme Tannase (EC 3.1.1.20), which has many applications is the food and pharmaceutical industry as it stands out for its ability to produce ellagic acid out of the enzymatic hydrolysis of ellagitannins. Ellagic acid has been studied in the medical area for its action against various diseases, as is the case of cancer or heart problems. The investigation was conducted to evaluate seven non-conventional yeasts - Debaryomyces hansenii PYC ISA 1510, Debaryomyces hansenii PYC 2968, Candida parapsilosis, Candida utilis, Pichia pastoris, Pichia kluyveri, Issatchenkia terricola - as producers of the enzyme tannase. This was done in mediums of fermentation with tannic acid (1-3%) and YPD without tannic acid, to determine the activity of the enzyme by two spectrophotometric methods, the first being with rhodamine and the second with methyl gallate, to detect the presence of gallic acid as a product of the hydrolysis of tannic acid. The main results showed that the evaluated non-conventional yeasts all presented activity with the Tannase enzyme, obtaining better detection results with the rhodamine technique for the stability of the formed complex, which gives more precision of the obtained data.

Abstract Characterize the content of phytochemical compounds present in samples of extracts of strawberry (Fragaria sp.) and blackberry (Rubus sp.). The extraction of said compounds was carried out with solutions of polar solvents, such as acetone, ethanol and methanol, using an experimental design with three factors: state of maturity, resting time and temperature. The characterization of these fruits is the beginning of the utilization mainly of ellagitannins to produce ellagic acid. Total phytochemical content was determined by spectrophotometric techniques, for phenolic content it was used Folin-Ciocalteu, for flavonoids it was determined with aluminium chloride, the antioxidant activity was evaluated by the methods of DPPH and ABTS+, the bactericidal effect of the extracts was shown for strains of E. coli and S. aureus. The determination of ellagitannins was performed by spectrometry. The influence of the state of maturity on the response variable was evaluated; it was observed that concentration of phytochemicals increases proportionally to maturity stage. The antioxidant activity was evaluated, determining that extracts obtained exhibit 94% - 95% inhibition. The determination of ellagitannins, finding that the highest concentration of ellagitannins was found in a state of green maturity, for strawberries as well as blackberries.