Hydrolytic enzyme production from açai palm (Euterpe precatoria) endophytic fungi and characterization of the amylolytic and cellulolytic extracts.

Enzymes are biocatalysts that are widely used in different industries and generate billions of dollars annually. With the advancement of biotechnology, new enzymatic sources are being evaluated, especially microbial ones, in order to find efficient producers. Endophytic fungi are promising sources of biomolecules; however, Amazonian species are still poorly studied as to their enzymatic production potential. In this sense, the production of hydrolases (amylases, lipases, cellulases and pectinases) was evaluated in endophytic fungi isolated from the leaves, roots and stems of açai palms (Euterpe precatoria). A qualitative test was carried out to detect the enzymatic synthesis in each isolate, and the most promising ones were cultivated using submerged fermentation. The enzyme extracts were quantified to determine those with the greatest activity. Cellulolytic and amylolytic extracts showed the highest enzymatic activities and were partially characterized. Among 50 isolates, 82.9% produced pectinase, 58.5% produced cellulase, 31.7% produced amylase, and 12.2% produced lipase. Penicillium sp. L3 was the best producer of amylase and Colletotrichum sp. S1 was the best producer of cellulase in liquid medium cultivation. The amylolytic extract showed the highest enzymatic activity at pH 8.0 and 45 °C, and the cellulolytic extract at pH 5.0 and 35 °C. The cellulase and amylase produced by the endophytes had their molecular masses estimated between 38 and 76 kDa. These results indicate that endophytic fungi from the açai palm can be used as a new source of hydrolytic enzymes, which can be applied in numerous biotechnological processes.

Optimization of bioprocess of Schleiferilactobacillus harbinensis Ca12 and its viability in frozen Brazilian berries (Açai, Euterpe oleracea Mart.).

Amazonian palm berries (açaí, Euterpe oleracea Mart.) are fruits with high nutritional value and antioxidant activity and have aroused the interest of consumers, popularizing fruit pulps enriched with probiotics. Amazonian palm berries (açaí, Euterpe oleracea Mart.) are fruits with high nutritional potential, providing a source of carbohydrates, fibers, proteins, lipids, vitamins, and minerals. Furthermore, açai provides several health benefits, including antioxidant activity. Nutritionally enhanced foods have aroused the interest of consumers, popularizing fruit pulps enriched with probiotics. Probiotics are dietary supplements consisting of live, beneficial microorganisms in the host which improve the intestinal microbiota. The objective of this study was to isolate, identify, and characterize the probiotic potential of an isolated Schleiferilactobacillus harbinensis strain (dubbed Ca12) and provide an optimized bioprocess for its production, using the complete factorial and central rotational compound design to supplement the frozen açai pulp. The isolated strain S. harbinensis Ca12 presented adequate resistance to gastric juice and bile salts, microbial activity against different Candida strains, self-aggregation and coaggregation properties, high adhesion in HT-29 cells, and 35% inhibition of Salmonella in HT-29 cells. When optimized, the cellular biomass production of the S. harbinensis Ca12 strain was approximately 600% higher than the unsupplemented whey, with a production of 3.6 × 1010 CFU mL-1. The S. harbinensis Ca12 strain's viability in the creamy and traditional frozen açai pulp was shown to be stable for up to 6 months at 20 °C. The impact of this study involved for the first time the S. harbinensis Ca12 described in the Brazilian cocoa pulp with activity against Candida albicans of clinical importance, creating the potential of a new functional food with important benefits to human health as prevention for candidiasis.

VOCs profile of Colletotrichum spp. as a potential tool for quality control of açaí pulp.

Colletotrichum has been identified as responsible for the "dried fruit" disease in açaí (Euterpe oleracea). Besides concern for açaí pulp quality control, the characterization of Colletotrichum has been difficult, which has motivated the search for chemical markers in the Volatile Organic Compounds (VOCs) profile for use as a tool in the identification of açaí pulp contaminated by the fungus. Extracted VOCs by Headspace - Solid Phase Micro Extraction (HS-SPME) were identified through gas chromatography mass spectrometry (GC-MS). From GC-MS analyzes 26 VOCs were identified, with a predominance of the terpenoids. Chemometrically, menthol and menthone were assigned as potential markers of the genus. The analysis of VOCs in açaí pulps contaminated by Colletotrichum under different cultivation conditions enabled the detection of menthone. This result illustrated the selectivity of the culture medium and the potential of this tool for use in the quality control of açaí pulp.

Effects of high hydrostatic pressure on the microbial inactivation and extraction of bioactive compounds from açaí (Euterpe oleracea Martius) pulp.

The aim of this study was to investigate the effects of high hydrostatic pressure (HHP) on the inactivation of Lactobacillus fructivorans, on the inactivation of Alicyclobacillus acidoterrestris spores and on the extraction of anthocyanins and total phenolics from açaí pulp. The tested conditions comprised pressures of 400-600 MPa, treatment times of 5-15 min, and temperatures of 25 °C and 65 °C. Results were compared to those of conventional thermal treatments (85 °C/1 min). Regarding A. acidoterrestris spores, applying HHP for 13.5 min, resulted in a value of four-decimal reduction. L. fructivorans presented considerable sensitivity to HHP treatment, achieving inactivation rates above 6.7 log cycles at process conditions at 600 MPa and 65 °C for 5 min. All samples of açaí pulp processed showed absence of thermotolerant coliforms during the 28 days of refrigerated storage (shelf life study). The açaí pulps processed by HHP (600 MPa/5 min/25 °C) had anthocyanin extraction increased by 37% on average. In contrast, conventional thermal treatment reduced anthocyanin content by 16.3%. For phenolic compounds, the process at 600 MPa/5 min/65 °C increases extraction by 10.25%. A combination of HHP treatment and moderate heat (65 °C) was shown to be an alternative to thermal pasteurization, leading to microbiologically safe products while preserving functional compounds.

Análise sensorial e avaliação da atividade antioxidante de iogurte adicionado de polpa de juçara para valoração do fruto / Sensorial analysis and evaluation of antioxidant activity of yogurt added of jussara pulp for valuation of the fruit

Estudos sobre compostos bioativos com propriedades antioxidantes apontam para benefícios à saúde através de seu uso. Inseridas nesse grupo estão as antocianinas, cujos efeitos se relacionam à redução do estresse oxidativo e dependem da absorção e interação com a microbiota humana. Um ensaio com sistema modelo de iogurte observou aumento da bioacessibilidade e da capacidade antioxidante das antocianinas presentes na juçara quando a fruta participa do processo fermentativo. O presente estudo avaliou a capacidade antioxidante do iogurte adicionado de polpa de juçara. Dessa forma, o iogurte adicionado de polpa foi submetido à quantificação e identificação de antocianinas, determinação da capacidade antioxidante e análise sensorial. Verificou-se que o iogurte desse estudo possui as potencialidades dos compostos presentes na juçara.

Qualidade microscópica e microbiológica de polpas de açaí congeladas comercializadas em supermercados de Teresina-PI / Microscopic and microbiological quality of frozen açai poles, marketed in Teresina-PI supermarkets

Falhas nas etapas do processamento do açaí afetam a qualidade da polpa. Desta forma, objetivou-se analisar a qualidade microscópica e microbiológica de polpas de açaí congeladas, comercializadas em supermercados de Teresina-PI. As amostras de açaí foram adquiridas em cincos supermercados e em seguidas foram submetidas às análises de sujidades e microbiológicas (Coliformes e Salmonella spp.). Os resultados microbiológicos indicaram que houve ausência de coliformes termotolerantes e Salmonella ssp. nas polpas de açaí analisadas. Todas as polpas analisadas apresentaram matérias estranhas tais como, fragmentos de insetos, pelo animal, filamentos de fungos, fibra sintética, fragmentos de caroço e casca e adulteração por adição de amido. Portanto, as polpas de açaí congeladas necessitam de atenção pelos órgãos fiscalizadores.

Importância do tratamento térmico para a qualidade microbiológica da polpa de açaí (Euterpe oleracea Mart) produzida e comercializada em Castanhal, Pará / The importance of heat treatment for the microbiological quality of açaí pulp (Euterpe oleracea Mart) produced and traded in Castanhal, Pará

Um dos problemas enfrentados durante a produção da polpa de açaí e devido ás condições higienicossanitárias dos estabelecimentos. Este trabalho objetivou avaliar a qualidade microbiológica da polpa de açaí em cinco estabelecimentos que produzem polpa de açaí localizados em Castanhal, PA. Foram realizadas análises microbiológicas. Aplicou-se a pasteurização nas polpas, na temperatura de 90 °C, por 60 segundos, a fim de verificar a sua influência sobre a qualidade microbiológica do produto. Os resultados microbianos mostraram que todas as amostras avaliadas antes da pasteurização apresentaram índices altos de contaminação. Após a pasteurização, todas as amostras apresentaram Número de Reduções Decimais – NRD, comprovando a eficiência da pasteurização. Os resultados evidenciam a importância do tratamento térmico para a qualidade do alimento.

Qualidade microbiológica de açaí comercializado na cidade de Guanambi-BA / Microbiological quality of açaí commercialized in the city of Guanambi-BA

Frutas são perecíveis e deterioram rapidamente, devido à sua variedade de nutrientes e a contaminação biológica. No entanto, quando se faz um processamento e congelamento de polpa de fruta há redução de perdas, traz praticidade, propicia a comercialização e conserva as características químicas e sensoriais da fruta in natura, como as polpas de açaí, que na maioria das vezes são comercializadas congeladas. Entretanto, à quebra da cadeia de frio durante a distribuição, compromete a qualidade da polpa de açaí, estando a contaminação desta polpa associada à baixa qualidade higiênico-sanitária durante a manipulação e o processamento da matéria-prima ou à uma contaminação dos equipamentos. Deste modo, o objetivo desse trabalho foi avaliar a qualidade microbiológica de açaí comercializado na cidade de Guanambi-BA. O açaí foi coletado de cinco estabelecimento do município, sendo as amostras coletadas com três repetições, uma a cada 7 dias. As polpas foram submetidas as análises microbiológicas de fungos filamentosos e leveduras, coliformes totais e termotolerantes. A legislação brasileira não apresenta um padrão para coliformes totais, mas estipula limite para coliformes termotolerantes e fungos filamentosos. De acordo com os resultados obtidos, o açaí de todos os pontos de coleta se apresentaram acima dos limites estabelecidos e, portanto, fora do padrão estipulado. Adoção e melhorias de medidas sanitárias, não só na comercialização do produto, mas desde a colheita dos frutos, são fundamentais para melhorias da condição microbiológica da comercialização das polpas de açaí.

Dynamics and diversity of the bacterial community during the spontaneous decay of açai (Euterpe oleracea) fruits.

The biodiversity and evolution of the microbial community in açai fruits (AF) between three geographical origins and two spontaneous decay conditions were examined by applying culture-independent methods. Culture-independent methods based on 16S rRNA from fifteen samples revealed that Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes and Acidobacteria were the most abundant phyla. At the genus level, Massilia (taxon with more than 50% of the sequences remaining constant during the 30h of decay), Pantoea, Naxibacter, Enterobacter, Raoultella and Klebsiella were identified, forming the carposphere bacterial microbiota of AF. AF is fibre-rich and Massilia bacteria could find a large quantity of substrate for its growth through cellulase production. Beta diversity showed that the quality parameters of AF (pH, soluble solids, titratable acidity and lipids) and elemental analysis (C, N, H and C/N ratio) were unable to drive microbial patterns in AF. This research offers new insight into the indigenous bacterial community composition on AF as a function of spontaneous postharvest decay.

Development of Yoghurt with Juçara Pulp (Euterpe edulis M.) and the Probiotic Lactobacillus acidophilus La5.

Yoghurts are dairy products consumed worldwide and can be supplemented with substances that provide extra health benefits as well as probiotic strains. In this context, the present study aimed to prepare a yoghurt added of juçara (Euterpe edulis M.) pulp and the commercial probiotic strain Lactobacillus acidophilus La5. Moreover, the probiotic survival during storage and after in vitro exposure to simulated gastric and enteric conditions was evaluated. Four formulations of yoghurt were prepared: (a) natural yoghurt, (b) yoghurt added of probiotic, (c) yoghurt added of juçara pulp, and (d) yoghurt added of probiotic culture and juçara pulp. The preparations were evaluated for survival of probiotic strain during storage and its tolerance to gastric and enteric conditions in vitro. The probiotic population in yoghurt remained unchanged during 28 days of storage. In addition, juçara pulp increased the probiotic resistance to simulated gastric and enteric conditions in the first day of storage. These data indicate that juçara pulp is a potential ingredient for the production of probiotic yoghurts.

Dynamics and diversity of the bacterial community during the spontaneous decay of açai (Euterpe oleracea) fruits

Abstract The biodiversity and evolution of the microbial community in açai fruits (AF) between three geographical origins and two spontaneous decay conditions were examined by applying culture-independent methods. Culture-independent methods based on 16S rRNA from fifteen samples revealed that Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes and Acidobacteria were the most abundant phyla. At the genus level, Massilia (taxon with more than 50% of the sequences remaining constant during the 30 h of decay), Pantoea, Naxibacter, Enterobacter, Raoultella and Klebsiella were identified, forming the carposphere bacterial microbiota of AF. AF is fibre-rich and Massilia bacteria could find a large quantity of substrate for its growth through cellulase production. Beta diversity showed that the quality parameters of AF (pH, soluble solids, titratable acidity and lipids) and elemental analysis (C, N, H and C/N ratio) were unable to drive microbial patterns in AF. This research offers new insight into the indigenous bacterial community composition on AF as a function of spontaneous postharvest decay.

Qualidade microbiológica de açaí industrializado / Microbiological quality of industrialized açai

Amostras de açaí (Euterpe oleracea Mart.) tipo fino congeladas e sem adição de quaisquer outros ingredientes foram adquiridas no comércio varejista da cidade do Rio de Janeiro. Foram analisadas microbiologicamente 54 amostras, pertencentes a 6 diferentes marcas (A, B, C, D, E e F). Todas as amostras analisadas encontravam-se dentro do prazo de validade estabelecido pelo fabricante e as empresas eram registradas no MAPA. Os micro-organismos analisados foram: Salmonella, Escherichia coli, fungos filamentosos e leveduras, de acordo com o preconizado pela legislação brasileira vigente. Considerando-se o limite máximo possível estabelecido pela lei, 2 lotes de cada marca B, E e F e 1 lote de cada marca C e D apresentaram contagens acima do permitido para fungos filamentosos e leveduras. Apenas 2 amostras apresentaram contagens de Escherichia coli, ambas estando fora do máximo estabelecido pela legislação vigente. Constatou- -se ausência de Salmonella em todas as amostras analisadas. A presença de fungos filamentosos, leveduras e Escherichia coli pode ser um indicativo de práticas inadequadas durante a fabricação do açaí. Assim, é importante ressaltar a necessidade de um controle rigoroso da cadeia do frio, uma vez que esses micro-organismos podem ser responsáveis pela deterioração do produto.

Perfil microbiológico do palmito de açaí (Euterpe oleracea MART) em conserva e das superfícies envolvidas na sua produção / Microbiological profile açaí palm heart (Euterpe oleracea MART) preserved and the areas involved in the production

Nos últimos anos o palmito vem sendo considerado uma iguaria tipicamente brasileira, consumido em diversos Estados como um produto exótico, muito utilizado na elaboração de pratos finos, com demanda não somente no mercado nacional, mas internacional também. Em contrapartida, é considerado um dos principais "vilões" de muitos casos de doenças causadas por alimentos contaminados. Assim, o presente trabalho objetivou avaliar a qualidade microbiológica do palmito de açaí (Euterpe oleracea Mart.) em conserva e das superfícies de contato envolvidas com o processamento do produto, em uma indústria localizada no município de Igarapé-Miri, no Pará. Foram coletadas cinco amostras do palmito de açaí em conserva e da salmoura em que se encontravam os produtos. As coletas foram realizadas em cinco dias diferentes. Todas as análises microbiológicas (Coliformes totais e termotolerantes, Clostridium Sulfito Redutor e Pesquisa de Salmonella spp.) foram realizadas seguindo os métodos oficiais de American Public Health Association. As superfícies analisadas foram: mãos de três manipuladores, bancada, balde, pote de vidro para embalagem, gabarito de corte, placa de corte e faca. As análises realizadas nas superfícies foram: contagem padrão de bactérias aeróbias mesófilas, Coliformes totais e termotolerantes, e contagem de Staphylococcus aureus. Os resultados das análises microbiológicas mostraram que todas as amostras de palmito em conserva e das salmouras encontram-se dentro dos padrões microbiológicos vigentes, portanto em condições adequadas de consumo. As análises microbiológicas de swabs das superfícies mostraram que as superfícies avaliadas não apresentaram contaminação por Coliformes termotolerantes. Observou-se, porém, contagens elevadas de bactérias aeróbias mesófilas e Coliformes totais. Em relação às superfícies das mãos dos manipuladores, as mesmas apresentaram níveis elevados de Stahpylococcs aureus, Coliformes totais e bactérias aeróbias mesófilas, mostrando assim a inadequada condição higienicossanitária da indústria.

In recent years the palm has been considered a typically Brazilian delicacy, consumed in several States as an exotic product, widely used in the production of fine dishes, becoming a product with demand not only in domestic market but also internationally. However, it is considered one of the "villains" of many cases of diseases caused by contaminated food. Thus, this study aimed to evaluate the microbiological quality açai palm heart (Euterpe oleracea Mart.) Canned and contact surfaces involved in product processing, in an industry in the municipality of Igarapé-Miri, Para. Were collected five açai palm samples preserved and brine they were in the products. Samples were collected on five different days. All microbiological analyzes (Total and Thermotolerant Coliforms, Clostridium Sulfite Reducer and Research Salmonella spp.) Were performed following the official methods of the American Public Health Association. The areas analyzed were the hands of three handlers, bench, bucket, glass jar for packaging, cutting template, cutting board and knife. The analyzes carried out on the surfaces were standard count mesophilic aerobic bacteria, Total and Thermotolerant Coliforms, and count Staphylococcus aureus. The results of these analyzes showed that all samples palm preserves and pickles are within agreed microbiological standards, so in appropriate conditions of use. Microbiological analysis of "swabs" from surfaces showed that the assessed surfaces were not contaminated by Coliform Thermotolerant. However, there was high counts of mesophilic aerobic bacteria and Total Coliform. With regard to areas of the hands of manipulators, they showed high levels of Stahpylococcs aureus, Total Coliforms and mesophilic aerobic bacteria, thus showing inadequate hygienic and sanitary condition of the industry.