ABSTRACT Edible mushroom species are considered as an adequate source of food in a healthy diet due to high content of protein, fiber, vitamins, and a variety of minerals. The representatives of Pleurotus genus are characterized by distinct gastronomic, nutritional, and medicinal properties among the edible mushrooms commercialized worldwide. In the present study, the growth of mycelial biomass of Pleurotus albidus cultivated in submerged fermentation was evaluated. Saccharose, fructose, and maltose were the three main carbon sources for mycelial biomass formation with corresponding yields of 7.28 g L−1, 7.07 g L−1, and 6.99 g L−1. Inorganic nitrogen sources did not stimulate growth and the optimal yield was significantly higher with yeast extract (7.98 g L−1). The factorial design used to evaluate the influence of saccharose and yeast extract concentration, agitation speed, and initial pH indicated that all variables significantly influenced the production of biomass, especially the concentration of saccharose. The greater amount of saccharose resulted in the production of significantly more biomass. The highest mycelial biomass production (9.81 g L−1) was reached in the medium formulated with 30.0 g L−1 saccharose, 2.5 g L−1 yeast extract, pH 7.0, and a speed of agitation at 180 rpm. Furthermore, P. albidus manifested different aspects of morphology and physiology under the growth conditions employed. Media composition affected mycelial biomass production indicating that the diversification of carbon sources promoted its improvement and can be used as food or supplement.

O beneficiamento do pirarucu (Arapaima gigas) gera grande quantidade de resíduos que podem ser aproveitados para a elaboração de novos produtos de interesse industrial. Este estudo objetivou avaliar a produção de hidrolisados proteicos a partir de resíduos de pirarucu, utilizando-se proteases de Aspergillus flavo-furcatis e pancreatina comercial, além de caracterizálos quanto às suas qualidades nutricional e microbiológica. A matéria-prima utilizada foi carne mecanicamente separada de carcaças de pirarucu (CMSP). Dois produtos foram desenvolvidos: um hidrolisado proteico de pirarucu produzido com enzima comercial (HPPEC) e outro com enzima microbiana (HPPEM). A CMSP e os hidrolisados foram submetidos à análise de composição química, qualidade microbiológica, grau de hidrólise, digestibilidade e perfil de aminoácidos. Os resultados mostraram que, no HPPEC, o teor proteico foi de 73,47 %, significativamente superior ao do HPPEM (58,03 %). Todavia, os dois produtos apresentaram altos valores de digestibilidade, ausência de contaminantes microbianos e redução no conteúdo de lipídios. Entre as enzimas utilizadas, a pancreatina foi a mais eficiente na elaboração do produto final, que demonstrou conteúdo de aminoácidos essenciais superior aos requerimentos para humanos adultos. O hidrolisado desenvolvido com as enzimas de A. flavo-furcatis apresentou escore de aminoácidos essenciais inferior a 1,0, sendo o aminoácido mais limitante o triptofano.

The processing of arapaima (Arapaima gigas) generates a lot of residues that can be used for the development of new products of industrial interest. This study aimed at evaluating the production of protein hydrolysates from arapaima residues using Aspergillus flavo-furcatis protease and commercial pancreatin, as well as characterizing their nutritional and microbiological qualities. The raw material used was meat mechanically separated from arapaima carcasses (MMSA). Two products were developed: a protein hydrolysate of arapaima using a commercial enzyme (PHACE) and another one using microbial enzyme (PHAME). The MMSA and the hydrolysates were analyzed for chemical composition, microbiological quality, degree of hydrolysis, digestibility and amino acid profile. The results showed that the PHACE protein content was 73.47 %. This value was significantly higher, when compared to the PHAME (58.03 %). However, both products showed high digestibility values, absence of microbial contaminants and reduced lipid content. Among the enzymes used, pancreatin was the most efficient one in the preparation of the final product, which showed essential amino acids content higher than the requirements for human adults. The hydrolysate developed using A. flavo-furcatis enzymes presented essential amino acids score lower than 1.0, being tryptophan the most limiting one.

Safety issues related to the employment of synthetic colorants in different industrial segments have increased the interest in the production of colorants from natural sources, such as microorganisms. Improved cultivation technologies have allowed the use of microorganisms as an alternative source of natural colorants. The objective of this work was to evaluate the influence of some factors on natural colorants production by a recently isolated from Amazon Forest, Penicillium purpurogenum DPUA 1275 employing statistical tools. To this purpose the following variables: orbital stirring speed, pH, temperature, sucrose and yeast extract concentrations and incubation time were studied through two fractional factorial, one full factorial and a central composite factorial designs. The regression analysis pointed out that sucrose and yeast extract concentrations were the variables that influenced more in colorants production. Under the best conditions (yeast extract concentration around 10 g/L and sucrose concentration of 50 g/L) an increase of 10, 33 and 23% respectively to yellow, orange and red colorants absorbance was achieved. These results show that P. purpurogenum is an alternative colorants producer and the production of these biocompounds can be improved employing statistical tool.

A full two-level factorial design was employed to study the influence of PEG molar mass (MM PEG), PEG concentration (C PEG) and phosphate concentration (C PHOSPH) on proteases partition by Lentinus citrinus DPUA 1535 in a PEG/phosphate aqueous two-phase system (ATPS). For all ATPS studied, proteases partitioned for the top phase and the best proteases extraction condition was obtained with MM PEG = 6000 g mol-1, C PEG = 17.5% (w/w) and C PHOSPH = 25% (w/w) with (1.1) purification factor and (151%) activity yield. Findings reported here demonstrate a practical strategy that serves as a first step for proteases purification from crude extract by L. citrinus.

Tropical forests are species-rich reserves for the discovery and development of antimicrobial drugs. The aim of this work is to investigate the in vitro antimicrobial potential of Amazon plants found within the National Institute on Amazon Research's Adolpho Ducke forest reserve, located in Manaus, state of Amazonas, Brazil. 75 methanol, chloroform and water extracts representing 12 plant species were tested for antimicrobial activity towards strains of Mycobacterium smegmatis, Escherichia coli, Streptococcus sanguis, Streptococcus oralis, Staphylococcus aureus and Candida albicans using the gel-diffusion method. Active extracts were further evaluated to establish minimum inhibitory concentrations (MIC) and antimicrobial profiles using bioautography on normal-phase thin-layer chromatography plates. Diclinanona calycina presented extracts with good antimicrobial activity and S. oralis and M. smegmatis were the most sensitive bacteria. D. calycina and Lacmellea gracilis presented extracts with the lowest MIC (48.8 µg/ml). D. calycina methanol and chloroform leaf extracts presented the best overall antimicrobial activity. All test organisms were sensitive to D. calycina branch chloroform extract in the bioautography assay. This is the first evaluation of the biological activity of these plant species and significant in vitro antimicrobial activity was detected in extracts and components from two species, D. calycina and L. gracilis.

O objetivo deste trabalho foi identificar 50 leveduras isoladas a partir de diferentes substratos da Região Amazônica e selecionar uma espécie de maior atividade proteolítica. Entre as 26 espécies identificadas predominaram Candida aquatica (12%) e Candida tropicalis (10%). A fermentação submersa foi realizada em Extrato de Malte suplementado com gelatina 1%, Candida intermedia foi a que expressou maior atividade proteolítica, halo = 25 mm e 273 U/mL, crescimento máximo a 30 ºC, viabilidade celular 6,2 x 10(6) UFC, em 48 horas, não demonstrou características de patogenicidade e a melhor densidade do inóculo foi 3%, utilizando-se culturas com 24 horas de crescimento em ágar Malte.

The objective of this work was to identify 50 yeasts isolates obtained from differents substracts from Amazon Region and to select one species of higher proteolytic activity. Among the 26 identified species it had predominance of Candida aquatica (12%) and Candida tropicalis (10%). The submerged fermentation was carried out in Malt Extract supplemented with gelatin 1%, Candida intermedia exhibited higher proteolytic activity, halo = 25 mm and 273U/mL, the maximum growth 30 ºC, the cellular viability 6.2 x 10(6) UFC, in 48 hours, did not demonstrate pathogenicity characteristics and the best inoculum density tested was 3%, using 24 hours Malt agar cultures.