Production of carotenoids by Chryseobacterium sp. strain Kr6 using feather meal as substrate

A obtenção de pigmentos carotenóides a partir de microrganismos é uma alternativa com elevado potencial de aplicação biotecnológica, em virtude de possibilitar melhor controle do processo e maior produtividade. Além disso, a utilização de resíduos agroindustriais como substratos para tais cultivos possibilita a redução dos custos de produção, podendo agregar valor a subprodutos potencialmente poluentes. A bactéria Chryseobacterium sp. linhagem kr6 apresenta elevada capacidade de sintetizar pigmentos carotenóides. O presente trabalho teve como principal objetivo avaliar a extração dos carotenóides produzidos por Chryseobacterium sp. kr6, empregando farinha de penas como única fonte de carbono. As melhores condições para a produção dos carotenóides foram obtidas a 30°C, 100 rpm, durante 48 h, com 5 g/L de farinha de penas, obtendo-se 64.575 μg/g de carotenóides. A otimização das condições de extração dos pigmentos a partir da biomassa foi realizada com o auxílio das ferramentas estatísticas de planejamento fatorial e metodologia de superfície de resposta. As condições que proporcionaram maior extração foram aplicação de ultra-som por 30 min com solvente acetona e (1:9) g/mL de biomassa úmida. O teor médio de carotenóides obtido foi de 180.000 ug/g, com temperatura mantida a 30ºC. A capacidade antioxidante dos carotenóides foi avaliada pela captura do radical DPPH● e produção de substâncias reativas ao ácido tiobarbitúrico (TBARS). Observou-se que o composto carotenóide apresenta atividade antioxidante por ambos os métodos. O composto de pigmentos carotenóides presentes no cultivo foi então parcialmente identificado por cromatografia em camada delgada comparativa (CCDC), sugerindo a presença de duas moléculas pertencente ao grupo das xantofilas (carotenóides oxigenados).Obtaining carotenoid pigments by microbial grown is an alternative with high potential for biotechnological application, because of the better process control and elevated productivity. Besides, the use of agro-industrial waste as substrate enables a reduction of the production cost, contributing in the treatment of potentially pollutants. The bacterium Chryseobacterium sp. strain kr6 shows high capacity to synthesize carotenoid pigments. The main objective of this work was to evaluate the extraction of carotenoids produced by Chryseobacterium sp. kr6, growing on feather meal as the sole carbon source. The best conditions for the production of the caronotenoids were obtained at 30ºC, 100 rpm, during 48 h, with 5 g/L of feather meal, obtaining 64.575 μg/g of carotenoids. The optimization of the pigment extraction conditions from the biomass was performed with the aid of factorial design and response surface methodology as statistical tools. The conditions that provided better extraction were ultrasound treatment for 30 min with acetone as solvent in a ratio of 1:9 (g/mL) of humid biomass. The average content of carotenoids obtained was 180,000 μg/g with temperature at 30ºC. The antioxidant capacity of the carotenoids was measured by the scavenging of DPPH● and production of thiobarbituric acid reactive substances (TBARS). It was observed that the carotenoid pigments presented antioxidant activity by both methodologies. The carotenoid pigments were partially indentified by comparative thin layer chromatography (TLC), suggesting the presence of two molecules belonging to the xantophiles group (oxygenated carotenoids)

Production, Extraction and Partial Characterization of Natural Pigments from <i>Chryseobacterium</i> sp. kr6 Growing on Feather Meal Biomass

Obtaining natural pigments from microorganisms is an alternative with high potential for biotechnological application. The use of agro-industrial wastes as substrate for cultivations enables a reduction of the production cost and may add value to potentially polluting byproducts. In this work, the extraction of pigments produced by the bacterium Chryseobacterium sp. strain kr6 was evaluated, employing feather meal as the sole carbon source for bacterial growth. The maximum production of the yellow pigments was observed for cultivation at 30 °C, during 48 h, with 5 g/L feather meal. The pigment extraction from the bacterial biomass was performed with the aid of physical methods and the testing of different organic solvents. The conditions that provided better extraction were using ultrasound with acetone as the solvent, reaching a yield of 180 μg/g biomass after optimization. The pigment was partially characterized via UV-visible, FTIR and mass spectroscopy and CIELAB color parameters, suggesting the presence of molecules belonging to the flexirubin group (aryl polyenes). The antioxidant capacity of the pigment was confirmed via the scavenging of DPPH radical and thiobarbituric acid reactive substances (TBARS) methodologies. Moreover, the pigment extract showed antimicrobial activity against Staphylococcus aureus and Enterococcus faecalis