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Lipases comprise the third most commercialized group of enzymes worldwide and those of microbial origin are sought for their multiple advantages. Agro-industrial waste can be an alternative culture medium for producing lipases, reducing production costs and the improper disposal of waste frying oil (WFO). This study aimed to produce yeast lipases through submerged fermentation (SF) using domestic edible oil waste as inducer and alternative culture medium. The optimal culture conditions, most effective inducer, and purification method for a new lipase from Moesziomyces aphidis BRT57 were identified. Yeast was cultured in medium containing green coconut pulp and WFO waste for 72 h. The maximum production of lipases in SF occurred in a culture medium containing WFO and yeast extract at 48 and 72 h of incubation, with enzyme activities of 8.88 and 11.39 U mL-1, respectively. The lipase was isolated through ultrafiltration followed by size exclusion chromatography, achieving a 50.46 % recovery rate. To the best of our knowledge, this is the first study to report the production and purification of lipases from M. aphidis, demonstrating the value of frying oil as inducer and alternative medium for SF, contributing to the production of fatty acids for biodiesel from food waste.
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Cocos , Lipase , Lipase/isolamento & purificação , Lipase/química , Lipase/biossíntese , Lipase/metabolismo , Cocos/química , Óleos de Plantas/química , Fermentação , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/química , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/genéticaRESUMO
Probiotic viability, metabolite concentrations, physicochemical parameters, and volatile compounds were characterized in Gueuze beers formulated with probiotic lactic acid bacteria (LAB) and yeast. Additionally, the sensory profile of the beers and the resistance of the probiotics to digestion were determined. The use of 2 International Bitterness Units resulted in high concentrations of probiotic LAB but a decline in probiotic yeast as pH decreased. Secondary fermentation led to the consumption of maltose, citric acid, and malic acid, and the production of lactic and propionic acids. Carbonation and storage at 4 °C had minimal impact on probiotic viability. The addition of probiotic LAB resulted in a distinct aroma profile with improved sensory characteristics. Our results demonstrate that sour beers produced with probiotic LAB and a probiotic yeast, and fermented using a two-step fermentation process, exhibited optimal physicochemical parameters, discriminant volatile compound profiles, promising sensory characteristics, and high probiotic concentrations after digestion.
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Cerveja , Fermentação , Probióticos , Paladar , Compostos Orgânicos Voláteis , Cerveja/análise , Cerveja/microbiologia , Probióticos/metabolismo , Probióticos/análise , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/química , Humanos , Digestão , Lactobacillales/metabolismo , Lactobacillales/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/química , Viabilidade MicrobianaRESUMO
Investigating the biotechnological potential of wild microorganisms is paramount for optimizing bioprocesses. Given this premise, we looked for yeasts in Brazilian native stingless bees, considering the recognized potential of pollinating insect-associated microorganisms for the production of volatile organic compounds (VOCs). Two yeast strains of the species Meyerozyma caribbica were isolated from bees Scaptotrigona postica and evaluated for their fermentative capacity. Both yeasts were capable of fermenting sucrose (the main sugar used in the Brazilian ethanol industry) with over 90% efficiency and yields of up to 0.504 g/g. Through an experimental design analysis (CCD), it was verified that the ethanol productivity of these yeasts can also benefit from high concentrations of sucrose and low pH values, desirable traits for microorganisms in this biofuel production. At the same time, CCD analyses also showed the great capacity of these M. caribbica strains to produce another alcohol of broad biotechnological interest, 2-phenylethanol. Interestingly, the statistical analyses demonstrated that greater production of this compound can occur at high sugar concentrations and low availability of nitrogen sources, which can be easily achieved using residual low-cost feedstocks. Thus, our results suggest that these M. caribbica strains may be efficiently used in both ethanol and 2-phenylethanol production.
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The influence of magnetic fields on biological systems, including fermentation processes and cocoa bean fermentation, is an area of study that is under development. Mechanisms, such as magnetosensitivity, protein conformational changes, changes to cellular biophysical properties, ROS production, regulation of gene expression, and epigenetic modifications, have been identified to explain how magnetic fields affect microorganisms and cellular processes. These mechanisms can alter enzyme activity, protein stability, cell signaling, intercellular communication, and oxidative stress. In cacao fermentation, electromagnetic fields offer a potential means to enhance the sensory attributes of chocolate by modulating microbial metabolism and optimizing flavor and aroma development. This area of study offers possibilities for innovation and the creation of premium food products. In this review, these aspects will be explored systematically and illustratively.
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Los postbióticos fueron definidos en 2021 por la Asociación Científica Internacional de Probióticos y Prebióticos (ISAPP) como "una preparación de microorganismos inanimados y/o sus componentes celulares capaces de conferir un efecto benéfico al hospedador". El campo de los postbióticos es un área nueva dentro de la familia de los bióticos; se han desarrollado ya numerosos productos con aplicaciones clínicas, como la estimulación inmunológica, el manejo de diarreas en niños y adultos, el abordaje del intestino irritable, además de tres fórmulas infantiles. En particular, las fórmulas infantiles con postbióticos obtenidos a partir de la fermentación de la leche con Bifidobacterium breve C50 y Streptococcus thermophilus O65, y sus metabolitos, incluido el oligosacárido 3'-GL, han demostrado seguridad y contribución al desarrollo de la microbiota intestinal y el sistema inmune asociado al intestino. Estas modificaciones contribuyen a la prevención y el manejo de los trastornos funcionales digestivos del lactante.
Postbiotics were defined in 2021 by the International Scientific Association for Probiotics and Prebiotics (ISAPP) as a "preparation of inanimate microorganisms and/or their cellular components that confers a health benefit to the host." The field of postbiotics is a new area within the biotics family; numerous products have already been developed for clinical applications, such as immune stimulation, the management of diarrhea in children and adults, the management of irritable bowel syndrome, and 3 infant formulas. In particular, infant formulas with postbiotics obtained from milk fermented with Bifidobacterium breve C50 and Streptococcus thermophilus O65 and their metabolites, including the oligosaccharide 3'-GL, have demonstrated to be safe and to contribute to the development of the gut microbiota and the gutassociated immune system. These modifications help to prevent and manage functional gastrointestinal disorders in infants.
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Humanos , Lactente , Probióticos , Síndrome do Intestino Irritável/microbiologia , Síndrome do Intestino Irritável/terapia , Fórmulas Infantis , Streptococcus thermophilus , Diarreia/microbiologia , Diarreia/terapia , Prebióticos/administração & dosagem , Microbioma Gastrointestinal , Bifidobacterium breve , Gastroenteropatias/microbiologia , Gastroenteropatias/terapiaRESUMO
Very high gravity (VHG) fermentation is an industrial-scale process utilizing a sugar concentration above 250 g/L to attain a significant ethanol concentration, with the advantages of decreased labor, production costs, water usage, bacterial contamination, and energy consumption. Saccharomyces cerevisiae is one of the most extensively employed organisms in ethanol fermentation through VHG technology. Conversely, high glucose exposure leads to numerous stress factors that negatively impact the ethanol production efficiency of this organism. Here, the impact of various phytochemicals added to the VHG medium on viability, glucose consumption, ethanol production efficiency, total antioxidant-oxidant status (TAS and TOS), and the response of the enzymatic antioxidant system of yeast were investigated. 2.0 mM naringenin and caffeic acid increased ethanol production by 2.453 ± 0.198 and 1.261 ± 0.138-fold, respectively. The glucose consumption rate exhibited a direct relationship with ethanol production in the naringenin-supplemented group. The highest TAS was determined as 0.734 ± 0.044 mmol Trolox Eq./L in the same group. Furthermore, both phytochemical compounds exhibited robust positive correlations with TAS (rnaringenin = 0.9986; rcaffeic acid = 0.9553) and TOS levels (rnaringenin = -0.9824; rcaffeic acid = -0.9791). While naringenin caused statistically significant increases in glutathione reductase (GR) and thioredoxin reductase (TrxR) activities, caffeic acid significantly increased TrxR and superoxide dismutase (SOD). Both phytochemicals seem to impact the ethanol production ability by regulating the redox status of the cells. We believe that the incorporation of particularly cost-effective antioxidants into the fermentation medium may serve as an alternative way to enhance the efficiency of bioethanol production using VHG technology.
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Due to the electrical nature of the cell, it is possible to modulate its behavior through the application of non-lethal external electric fields to improve fermentation processes. In this work, a microbial cell system with a chamber and two electrodes inside and connected to a voltage source was used. One of the electrodes was kept isolated to create an electric field without the flow of current. Cultures with two ethanol-producing microbial strains (Saccharomyces cerevisiae and Zymomonas mobilis) were conducted in this device. The application of voltages between 0 and 18 V was evaluated to determine the impact of the generated electric field on ethanol production. To analyze the possible effect of the field on the central carbon metabolism in each strain, biochemical-based kinetic models were formulated to describe the experimental fermentation kinetics obtained. It was found that low applied voltages did not have significant effects on growth rate in either strain, but all voltages evaluated increased substrate consumption and ethanol production rate in Z. mobilis, while only 18 V affected these rates in S. cerevisiae, indicating that Z. mobilis was the most sensitive to the electric field. At the end of the fermentation, significant increases in ethanol yields of 10.7% and 19.5% were detected for S. cerevisiae and Z. mobilis, respectively. The proposed mathematical models showed that substrate transport through the membrane catalyzed by the phosphotransferase system (PTS) for Z. mobilis and hexose transport proteins mechanism and hexokinase (HK) activity for S. cerevisiae and the transformation of pyruvate to ethanol, catalyzed by the decarboxylase (PDC) and alcohol dehydrogenase (ADH) enzymes, were the reactions most affected by the application of the external field.
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p-Coumaric acid (p-CA) is a valuable compound with applications in food additives, cosmetics, and pharmaceuticals. However, traditional production methods are often inefficient and unsustainable. This study focuses on enhancing p-CA production efficiency through the heterologous expression of tyrosine ammonia-lyase (TAL) from Rhodobacter sphaeroides in Pseudomonas putida KT2440. TAL catalyzes the conversion of L-tyrosine into p-CA and ammonia. We engineered P. putida KT2440 to express TAL in a fed-batch fermentation system. Our results demonstrate the following: (i) successful integration of the TAL gene into P. putida KT2440 and (ii) efficient bioconversion of L-tyrosine into p-CA (1381 mg/L) by implementing a pH shift from 7.0 to 8.5 during fed-batch fermentation. This approach highlights the viability of P. putida KT2440 as a host for TAL expression and the successful coupling of fermentation with the pH-shift-mediated bioconversion of L-tyrosine. Our findings underscore the potential of genetically modified P. putida for sustainable p-CA production and encourage further research to optimize bioconversion steps and fermentation conditions.
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The advancement of fungal biocontrol agents depends on replacing cereal grains with low-cost agro-industrial byproducts for their economical mass production and development of stable formulations. We propose an innovative approach to develop a rice flour-based formulation of the beneficial biocontrol agent Trichoderma asperelloides CMAA1584 designed to simulate a micro-bioreactor within the concept of full biorefinery process, affording in situ conidiation, extended shelf-life, and effective control of Sclerotinia sclerotiorum, a devastating pathogen of several dicot agricultural crops worldwide. Rice flour is an inexpensive and underexplored byproduct derived from broken rice after milling, capable of sustaining high yields of conidial production through our optimized fermentation-formulation route. Conidial yield was mainly influenced by nitrogen content (0.1% w/w) added to the rice meal coupled with the fermentor type. Hydrolyzed yeast was the best nitrogen source yielding 2.6 × 109 colony-forming units (CFU)/g within 14 days. Subsequently, GControl, GLecithin, GBreak-Thru, GBentonite, and GOrganic compost+Break-Thru formulations were obtained by extrusion followed by air-drying and further assessed for their potential to induce secondary sporulation in situ, storage stability, and efficacy against Sclerotinia. GControl, GBreak-Thru, GBentonite, and GOrganic compost+Break-Thru stood out with the highest number of CFU after sporulation upon re-hydration on water-agar medium. Shelf-life of formulations GControl and GBentonite remained consistent for > 3 months at ambient temperature, while in GBentonite and GOrganic compost+Break-Thru formulations remained viable for 24 months during refrigerated storage. Formulations exhibited similar efficacy in suppressing the myceliogenic germination of Sclerotinia irrespective of their concentration tested (5 × 104 to 5 × 106 CFU/g of soil), resulting in 79.2 to 93.7% relative inhibition. Noteworthily, all 24-month-old formulations kept under cold storage successfully suppressed sclerotia. This work provides an environmentally friendly bioprocess method using rice flour as the main feedstock to develop waste-free granular formulations of Trichoderma conidia that are effective in suppressing Sclerotinia while also improving biopesticide shelf-life. KEY POINTS: ⢠Innovative "bioreactor-in-a-granule" system for T. asperelloides is devised. ⢠Dry granules of aerial conidia remain highly viable for 24 months at 4 °C. ⢠Effective control of white-mold sclerotia via soil application of Trichoderma-based granules.
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Ascomicetos , Reatores Biológicos , Fermentação , Oryza , Esporos Fúngicos , Reatores Biológicos/microbiologia , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Oryza/microbiologia , Esporos Fúngicos/crescimento & desenvolvimento , Nitrogênio/metabolismo , Hypocreales/metabolismo , Hypocreales/crescimento & desenvolvimento , Agentes de Controle Biológico/química , Trichoderma/metabolismo , Trichoderma/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controleRESUMO
BACKGROUND: A colorimetric method for the quantification of hydrogen sulfide (H2S) produced in microbial fermentations was developed using lead gelled alginate microparticles packed in glass columns. The formation of a lead sulfide complex, between H2S and lead ion (Pb2+) immobilized on the microparticles, allowed simple and accurate quantification by colorimetry. RESULTS: The microparticle-loaded columns were calibrated and showed significant analytical sensitivity. The calibration curve of the system showed a correlation coefficient (r2) of 0.995 and a detection limit of 1.29 ± 0.02 µg L-1. The application of the columns in laboratory wine fermentations was able to detect variations in H2S production from 10.6 to 23.5 µg L-1 by increasing the sugar content in the medium, and from 10.6 to 3.2 µg L-1 with decreasing nitrogen content in the medium. CONCLUSION: Validation of the proposed method was carried out by determining H2S in a vinic fermentation model, the results of which were compared with those obtained using a reference chemical method. The data obtained showed no statistically significant differences between the two methods, confirming the reliability and accuracy of the developed system. © 2024 Society of Chemical Industry.
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This study investigated the health-functional properties of a lactic fermented pomegranate juice (FPJ) enriched with pomegranate seed oil (FPJO) by using the fruit-origin strain Lactiplantibacillus paraplantarum CRL 2051 (FPJO-CRL2051). For this aim, the in vitro human antiplatelet aggregation effect and antioxidant activities were determined in the fermented juices while in vivo studies using high-fat-diet (HFD) C57BL/6 mice fed with a high-fat diet or pomegranate fermented juices for 8 weeks were performed. A high anti-platelet aggregation activity for FPJO-CRL2051 was determined. The formulated juice was administered to C57BL/6 HFD mice over 8 weeks, which showed a significant decrease in triglycerides, LDL-C, and pro-inflammatory cytokines levels. The FPJO-CRL2051 administration was effective in ameliorating liver damage caused by HFD, reducing fat accumulation and oxidative biomarkers, and improving the liver fatty acid profile by incorporation of conjugated fatty acids. This study shows the significance of lactic fermentation in developing novel fermented plant-based beverages with enhanced functional activities with a circular economy approach for the prevention of metabolic disorders.
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Yeast immobilization in beer fermentation has recently regained attention, due to the expansion of the craft beer market and the diversification of styles and flavors. The aim of this study was to evaluate the physiological differences between immobilized and free yeast cells with a focus on flavor-active compounds formation. Three strains of Saccharomyces spp. (SY025, SY067, SY001) were evaluated in both free and immobilized (using a cellulose-based support, referred as ImoYeast) forms during static batch fermentations of 12 °P malt extract. Immobilized cells showed higher glycerol (SY025, 40%; SY067, 53%; SY001, 19%) and biomass (SY025, 67%; SY067, 78%; SY001, 56%) yields than free cells. Conversely, free cells presented higher ethanol yield (SY025, 9%; SY067, 9%; SY001, 13%). Flavor-active compounds production exhibited significant alterations between immobilized and free cells systems, for all strains tested. Finally, a central composite design with varying initial biomass (X0) and substrate (S0) concentrations was conducted using strain SY025, which can be helpful to modulate the formation of one or more flavor-active compounds. In conclusion, yeast immobilization in the evaluated support resulted in flavor alterations that can be exploited to produce different beer styles.
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Cerveja , Células Imobilizadas , Fermentação , Aromatizantes , Saccharomyces , Cerveja/microbiologia , Cerveja/análise , Saccharomyces/metabolismo , Aromatizantes/metabolismo , Células Imobilizadas/metabolismo , Biomassa , Etanol/metabolismo , Glicerol/metabolismo , Saccharomyces cerevisiae/metabolismoRESUMO
The increase in the negative effects of global change promotes the search for alternatives to supply the demand for food worldwide aligned with the Sustainable Development Goals (SDGs) to ensure food security. Animal protein, which is a main source of nutrients in the diet of today's society, especially beef, which is one of the most demanded products nowadays, has been criticized not only for its high water consumption and land occupation for production but also for the emission of greenhouse gases (GHG) from enteric methane generated in the fermentation process within the bovine rumen and deforestation for the adaptation of pastures. This study is mainly motivated by the lack of quantifiable scientific information in Colombia on the environmental impacts of beef production. Therefore, it is intended to estimate some of the impacts of beef production in extensive systems using the life cycle assessment (LCA) method under a particular scenario considering all the production phases (from raw material to fattening, where the cattle are ready to be slaughtered). The study was conducted with data supplied by a farm in Antioquia, Colombia, and the functional unit (FU) was defined as 1 kg of live weight (LW). The scope of this study was gate-to-gate. "The 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories" (IPCC 2006; IPCC 2019) was used to calculate methane and nitrous oxide emissions. LCA modeling was developed with Ecoinvent database v3.8 and the Umberto LCA + software. It was found that the most affected category of damage was ecosystem quality, which represents 77% of the total, followed by human health at 17% and resources at 6%. The category impact of agricultural land occupation is the one that represents the most significant contribution to the ecosystem quality endpoint, with a percentage of 87%, due to the soil's compaction and the loss of the soil's properties. Additionally, the obtained carbon footprint for the system was 28.9 kg of CO2-eq/kg LW.
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Gases de Efeito Estufa , Colômbia , Bovinos , Animais , Gases de Efeito Estufa/análise , Meio Ambiente , MetanoRESUMO
This study aimed to evaluate the effect of nano-encapsulation of four essential amino acids (AA), threonine, methionine, tryptophan, and lysine on in vitro ruminal total gas, methane, carbon monoxide, and hydrogen sulfide production as well as the rumen fermentation profile in cattle. The highest (P < 0.001) rate and asymptotic gas production after 48 h of incubation was observed in the diets that had threonine, followed by lysine, methionine, and tryptophan. Asymptotic methane gas production decreased in the following order: threonine > lysine > tryptophan > methionine (P < 0.0001) and the rate of production per hour followed the same trend (P = 0.0259). CH4 parameters showed that in 4 h, 24 h, and 48 h of incubation the lowest methane production was obtained in the diet with methionine (P < 0.05) and the highest one in diet supplemented with threonine. Methane fractions showed that methionine-containing diets resulted in more (P < 0.05) metabolizable energy versus methane, followed by tryptophan-containing, and then lysine-containing diets. Methionine-fortified diets seem to be the most eco-friendly among those studied regarding methane output. However, based on methane, CO, and H2S output as well as the rumen fermentation profile nano-encapsulated lysine is recommended for use in ruminant nutrition.
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The interest in natural compounds has increased primarily due to their beneficial health and environmental aspects. However, natural sources of some compounds, such as bluish pigments, are limited, requiring the development of efficient processes to meet commercial demands. This study isolated a blue-violet bacterium from spoiled cooked rice and identified it as a potential new species of Janthinobacterium through 16S rDNA analysis. Ultra-high performance liquid chromatography-tandem mass spectrometry analyses confirmed that the blue-violet pigment violacein was responsible for the bluish color. In laboratory conditions, different carbon and nitrogen sources were evaluated in submerged culture media to enhance pigment production. Glycerol did not result in significant pigment production by this strain, as expected from previous reports. Instead, a culture medium composed of yeast extract and fructose yielded higher pigment production, reaching about 113.68 ± 16.68 mg l-1 after 120 h. This result provides crucial insights for future studies aiming for sustainable and commercially viable violacein production. Based on a bioeconomy concept, this approach has the potential to supply natural and economic bluish pigments for various industrial sectors, including pharmaceutical, cosmetic, and food.
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Meios de Cultura , Indóis , Oxalobacteraceae , Pigmentos Biológicos , Indóis/metabolismo , Meios de Cultura/química , Pigmentos Biológicos/biossíntese , Oxalobacteraceae/metabolismo , Oxalobacteraceae/genética , Oxalobacteraceae/isolamento & purificação , Oxalobacteraceae/classificação , RNA Ribossômico 16S/genética , Oryza/microbiologia , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta PressãoRESUMO
Alcoholic fermentation is one of man's most efficient food preservation processes, and innovations in this area are a trend in food science and nutrition. In addition to the classic Saccharomyces yeasts, various other species may have desirable characteristics for obtaining fruit wines. This study investigated the profile of non-Saccharomyces commercial yeasts compared with S. cerevisiae regarding pineapple wine's chemical composition and bioaccessibility. The fermentation profile of the yeasts Lachancea thermotolerans, Brettanomyces bruxellensis, Brettanomyces lambicus, and S. cerevisiae was evaluated for sugar and alcohol content, and the pineapple wines obtained were analyzed for amino acids, phenolics, and organic acids by HPLC and volatile profile by GC/MS. All yeast strains were able to produce ethanol and glycerol at acceptable levels. L. thermotolerans produced higher levels of lactic acid (0.95 g/L) and higher consumption of free amino acids. B. bruxellensis produced higher levels of individual phenolics and ethanol 109 g/L. The alcoholic fermentation process improved the bioaccessibility of phenolics such as catechin (237 %), epigallocatechin gallate (81 %), procyanidin B1 (61 %) and procyanidin B2 (61 %). The yeasts differed in their volatile profiles, with Brettanomyces and Lachancea producing higher levels of compounds associated with pineapple aroma, such as ester ethyl butyrate (260-270 µg/L). These results demonstrate the importance of choosing the yeast strain for the conduction of alcoholic fermentation and that the yeasts Brettanomyces and Lachancea showed technological potential in obtaining pineapple wines. This study contributes to developing processes for obtaining fruit wines by highlighting two non-Saccharomyces yeast species with technological potential for alcoholic fermentations.
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Ananas , Etanol , Fermentação , Saccharomyces cerevisiae , Vinho , Vinho/análise , Ananas/química , Saccharomyces cerevisiae/metabolismo , Etanol/metabolismo , Etanol/análise , Fenóis/análise , Fenóis/metabolismo , Aminoácidos/análise , Aminoácidos/metabolismo , Brettanomyces/metabolismo , Saccharomycetales/metabolismo , Compostos Orgânicos Voláteis/análise , Cromatografia Gasosa-Espectrometria de Massas , Frutas/químicaRESUMO
Polyphenolic compounds are common constituents of human and animal diets and undergo extensive metabolism by the gut microbiota before entering circulation. In order to compare the transformations of polyphenols from yerba mate, rosemary, and green tea extracts in the gastrointestinal tract, simulated gastrointestinal digestion coupled with colonic fermentation were used. For enhancing the comparative character of the investigation, colonic fermentation was performed with human, pig and rat intestinal microbiota. Chemical analysis was performed using a HPLC system coupled to a diode-array detector and mass spectrometer. Gastrointestinal digestion diminished the total amount of phenolics in the rosemary and green tea extracts by 27.5 and 59.2 %, respectively. These reductions occurred mainly at the expense of the major constituents of these extracts, namely rosmarinic acid (-45.7 %) and epigalocatechin gallate (-60.6 %). The yerba mate extract was practically not affected in terms of total phenolics, but several conversions and isomerizations occurred (e.g., 30 % of trans-3-O-caffeoylquinic acid was converted into the cis form). The polyphenolics of the yerba mate extract were also the least decomposed by the microbiota of all three species, especially in the case of the human one (-10.8 %). In contrast, the human microbiota transformed the polyphenolics of the rosemary and green extracts by 95.9 and 88.2 %, respectively. The yerba mate-extract had its contents in cis 3-O-caffeoylquinic acid diminished by 78 % by the human microbiota relative to the gastrointestinal digestion, but the content of 5-O-caffeoylquinic acid (also a chlorogenic acid), was increased by 22.2 %. The latter phenomenon did not occur with the rat and pig microbiota. The pronounced interspecies differences indicate the need for considerable caution when translating the results of experiments on the effects of polyphenolics performed in rats, or even pigs, to humans.
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Colo , Depsídeos , Digestão , Fermentação , Ilex paraguariensis , Extratos Vegetais , Polifenóis , Ácido Rosmarínico , Rosmarinus , Animais , Humanos , Extratos Vegetais/metabolismo , Rosmarinus/química , Ratos , Ilex paraguariensis/química , Suínos , Depsídeos/metabolismo , Depsídeos/análise , Polifenóis/metabolismo , Polifenóis/análise , Colo/metabolismo , Colo/microbiologia , Masculino , Cinamatos/metabolismo , Cinamatos/análise , Microbioma Gastrointestinal , Chá/química , Ácido Quínico/análogos & derivados , Ácido Quínico/metabolismo , Ácido Quínico/análise , Catequina/análogos & derivados , Catequina/metabolismo , Catequina/análise , Cromatografia Líquida de Alta Pressão , Camellia sinensis/químicaRESUMO
Proteases are enzymes that hydrolyze peptide bonds present in proteins and peptides. They are widely used for various industrial applications, such as in the detergent, food, and dairy industries. Cheese is one of the most important products of the dairy industry, and the coagulation stage is crucial during the cheese-making process. Enzymatic coagulation is the most common technique utilized for this purpose. Microbial enzymes are frequently used for coagulation due to their advantages in terms of availability, sustainability, quality control, product variety, and compliance with dietary and cultural/religious requirements. In the present study, we identified and subsequently characterized milk coagulant activity from the fungus Pleurotus djamor PLO13, obtained during a solid-state fermentation process, using the agro-industrial residue, wheat bran, as the fermentation medium. Maximum enzyme production and caseinolytic activity occurred 120 h after cultivation. When the enzyme activity against various protease-specific synthetic substrates and inhibitors was analyzed, the enzyme was found to be a serine protease, similar to elastase 2. This elastase-2-like serine protease was able to coagulate pasteurized whole and reconstituted skim milk highly efficiently in the presence and absence of calcium, even at room temperature. The coagulation process was influenced by factors such as temperature, time, and calcium concentration. We demonstrate here, for the first time, an elastase-2-like enzyme in a microorganism and its potential application in the food industry for cheese production.