Actividad antifúngica de Bougainvillae spectabilis sobre aislados de Rhizopus nigricans y Penicillium expansum

In the last years the antimicrobial activity of essential oils and plant extracts has been recognized, therefore, they could be adopted by the food industry as preservatives against fungi in bakery products. In this work, the hexane, chloromethane and methanol extracts from flowers and bracts of Bougainvillea spectabilis were studied for their antifungal activity against Rhizopus nigricas, Penicillium expansum and Aspergillus niger isolated from bread. Inhibition was measured as a function of the biomass production, evaluated every six hours with hexane extract during 60 hours. The concentrations for R. nigricans were 250-1000 ppm and 3250-4000 for P. expansum with five replications. Data were analyzed using a completely randomized design and the Tukey test to perform a pairwise comparison of the means. Results showed that only the hexane extract exhibited antifungal activity against Rhizopus nigricas and Penicillium expansum . The highest inhibition for R. nigricas was at 1000 ppm whereas for P. expansum was 4000 at ppm. In this case, the statistical analysis did not show significative differences between the concentrations of 3250-3750 ppm. Natural alternatives are needed to achieve shelf-life of foods and food safety.