Resumo

Bixa orellana (urucu) is a small tree that grows 5-10 meters in height. The urucu fruit contains approximately 50 seeds, which are displaced inside a prickly reddish pods at the ends of the branches. Bixin is the major colorant of the urucu seed and more than 80% of the total carotenoids are displayed in the plants grain. Nowadays, pharmaceutics and food industries are demonstrating a great deal of interest in the tropical American seed of B. orellana due to its application as an antioxidant and food-dye potential. This natural pigment reflects a novel market tendency and is in accordance with recent government agencies laws which are restricting the amount of synthetic dyes used by the two businesses. In this present study levels of bixin were analyzed in two samples of extracts from two urucu shrubs: Peruana paulista and Embrapa 37 and its antimicrobial and antioxidant activity was evaluated by HPLC, MIC and Well diffusion test (WDT). Antioxidant activities were investigated by photon colorimetric assay against the stable 2, 2-diphenyl-1-picryhydrazyl radical (DPPH). Both extracts showed antioxidant activity, cultivar Embrapa 37 showed 54 µmolls of BHT and P. paulista 40 µmolls of BHT respectively. HPLC assays showed a higher level of bixin for cultivar Embrapa 37 (4.15 g/L) compared to P. paulista (1.93 g/L). After 90 days of storage, it was observed a reduction of 19.71% and 19.11% of P. paulista and Embrapa 37, respectively, of the bixin levels. Although cultivar P. paulista had a lower level of bixin when compared to Embrapa 37, both exhibited the same antimicrobial activity against different bacteria species. MIC tests with cultivar Embrapa 37 inhibited with 11.75, 5.87, 11.75 and 5.87 mg/ml for Staphylococcus aureus (ATCC 2952), Bacillus cereus (ATCC 11748), Bacillus subtilis (ATCC 19369) and Pseudomonas aeruginosa (ATCC 9542) respectively. While, cultivar P. paulista inhibited with 5.5 mg/ml for Listeria monocytogenes (ATCC 1937) Bacillus cereus (ATCC 11748), Bacillus subtilis (ATCC 19369) and Pseudomonas aeruginosa (ATCC 9542), respectively. With these results, it is possible to conclude that the bixin extract demonstrates a significant potential to be used as an antimicrobial agent by food and pharmaceutical industries.