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1.
Int J Food Microbiol ; 424: 110852, 2024 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-39141974

RESUMO

This study presents comprehensive insights into the microbiological profile across all concentrated chicken broth processing stages, utilizing a combination of amplicon sequencing based on metataxonomic and culturing techniques. Samples were systematically collected throughout the production chain, with each batch yielding 10 samples per day across eight different dates. These samples underwent thorough analysis, including 16S rRNA and ITS sequencing (n = 30), culture-dependent microbiological tests (n = 40), and physical-chemical characterization (n = 10). Culturing analysis revealed the absence of Listeria monocytogenes and Salmonella spp. at any stage of processing, counts of various microorganisms such as molds, yeasts, Enterobacteria, and others remained below detection limits. Notably, spore counts of selected bacterial groups were observed post-processing, indicating the persistence of certain species, including Bacillus cereus and Clostridium perfringens, albeit in low counts. Furthermore, the study identified a diverse array of bacterial and fungal species throughout the processing chain, with notable occurrence of spore-forming bacteria. The presence of spore-forming bacteria in the final product, despite thermal processing, suggests the need for enhanced strategies to mitigate their introduction and persistence in the processing premises. Thus, this study offers valuable insights into microbial dynamics and diversity through processing concentrated chicken broth.


Assuntos
Bactérias , Galinhas , Microbiologia de Alimentos , Fungos , Galinhas/microbiologia , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/crescimento & desenvolvimento , Animais , Manipulação de Alimentos/métodos , RNA Ribossômico 16S/genética , Contagem de Colônia Microbiana , Contaminação de Alimentos/análise , Meios de Cultura/química
2.
Food Chem ; 460(Pt 1): 140522, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39047492

RESUMO

This study evaluated the effect of dielectric barrier discharge (DBD) and glow discharge (glow) cold plasma treatments in color, sugars, organic acids, phenolics (concentration and bioaccessibility), antioxidant activity, volatiles, and microbiota of edible mini-roses. Plasma treatments did not affect the flowers' color, while they increased organic acids and phenolics. Flowers treated with DBD had a higher concentration of most phenolics, including hesperidin (84.04 µg/g) related to antioxidant activity, and a higher mass fraction of most volatiles, including octanal (16.46% after 5 days of storage). Flowers treated with glow had a higher concentration of pelargonidin 3,5-diglucoside (392.73 µg/g), greater bioaccessibility of some phenolics and higher antioxidant activity. Plasma treatments reduced the microbiota diversity in mini-roses. Regardless of the plasma treatment, phylum Proteobacteria, family Erwiniaceae, and genus Rosenbergiella were the dominant groups. Results indicate plasma treatments as promising technologies to improve the quality and increase phenolic and specific volatile compounds in mini-roses.


Assuntos
Bactérias , Microbiota , Fenóis , Gases em Plasma , Compostos Orgânicos Voláteis , Fenóis/metabolismo , Fenóis/química , Gases em Plasma/farmacologia , Gases em Plasma/química , Bactérias/metabolismo , Bactérias/classificação , Bactérias/isolamento & purificação , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Antioxidantes/metabolismo , Antioxidantes/química , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Flores/química , Flores/metabolismo
3.
Food Res Int ; 186: 114403, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729705

RESUMO

This study aimed to evaluate the functional, technological, and sensory aspects of mangaba (Hancornia speciosa Gomes) fruit pulp fermented with the probiotic Lacticaseibacillus casei 01 (LC1) during refrigerated storage (7 °C, 28 days). The effects of the fermented mangaba pulp on the modulation of the intestinal microbiota of healthy vegan adults were also assessed. Mangaba pulp allowed high viability of LC1 during storage and after simulated gastrointestinal conditions (≥7 log CFU/g). The fermented mangaba pulp showed lower pH and total soluble solids, and higher titratable acidity, and concentrations of lactic, acetic, citric, and propionic acids during storage compared to non-fermented pulp. Also, it presented a higher concentration of bioaccessible phenolics and volatiles, and improved sensory properties (yellow color, brightness, fresh appearance, and typical aroma and flavor). Fermented mangaba pulp added to in vitro cultured colonic microbiota of vegan adults decreased the pH values and concentrations of maltose, glucose, and citric acid while increasing rhamnose and phenolic contents. Fermented mangaba pulp promoted increases in the abundance of Dorea, Romboutsia, Faecalibacterium, Lachnospira, and Lachnospiraceae ND3007 genera and positively impacted the microbial diversity. Findings indicate that mangaba pulp fermented with LC1 has improved chemical composition and functionality, inducing changes in the colonic microbiota of vegan adults associated with potential benefits for human health.


Assuntos
Fermentação , Microbioma Gastrointestinal , Lacticaseibacillus casei , Humanos , Microbioma Gastrointestinal/fisiologia , Lacticaseibacillus casei/metabolismo , Adulto , Paladar , Probióticos , Masculino , Concentração de Íons de Hidrogênio , Frutas/microbiologia , Frutas/química , Colo/microbiologia , Colo/metabolismo , Adulto Jovem , Feminino
4.
Food Chem ; 435: 137640, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37804728

RESUMO

Physicochemical parameters, microbial diversity using sequencing and amplicon, and metabolite concentrations from Ginger Bug and Ginger Beer were characterized. Furthermore, the sensory aspects of the beverage were determined. The longer ginger bug activation time (96 h) resulted in higher production of organic acids and alcohols, increased phenolic and volatile compounds concentration, greater microbial diversity, and increased lactic acid bacteria and yeasts. In the same way, the longer fermentation time (14 days) of ginger beer resulted in higher ethanol content, volatile compounds, and phenolic compounds, in addition to better sensory characteristics. Our results showed that ginger beer produced with ginger bug and fermented for 14 days showed better volatile and phenolic compound profiles, physicochemical parameters, microbial diversity, and sensory characteristics.


Assuntos
Microbiota , Zingiber officinale , Cerveja , Fermentação , Zingiber officinale/química , Fenóis/análise
5.
Food Res Int ; 173(Pt 1): 113233, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803548

RESUMO

Mini-roses (Rosa chinensis Jacq.) is largely used in salty dishes and desserts. This study evaluated instrumental color, sugars, organic acids, phenolics, volatiles, and the indigenous microbiota (fungi and bacteria) in edible mini-roses farmed in discarded fruits biocompost and animal manure systems. A descriptive sensory analysis of flowers was also performed. Mini-roses farmed in biocompost had higher luminosity and intensity of instrumental red color, a higher concentration of phenolic compounds, including anthocyanins related to red color, and fructose than mini-roses farmed in animal manure (p < 0.05). Furthermore, mini-roses farmed in biocompost had higher concentrations of various volatiles (p < 0.05), including hexyl acetate and cis-3 -hexenyl butyrate related to the fruity aroma. Bacterial groups related to plant growth-promoting such as Stenotrophomonas and endophilic fungal groups such as Eurotiales sp, Pleosporales sp were found in higher abundance (p < 0.05) in mini-roses farmed in biocompost. Mini-rose farmed in biocompost also received higher score (p < 0.05) for fruity aroma and red color than mini-rose mini-roses farmed in animal manure. Results indicate that farming mini-roses using biocompost from discarded fruits impacts the synthesis of phenolics and volatiles, resulting in a more intense fruity aroma and red color. Findings also suggest that the microbiota of mini-roses farmed in biocompost or animal manure do not represent a major risk for the safety of these products.


Assuntos
Antocianinas , Rosa , Animais , Odorantes , Esterco , Agricultura
6.
Food Res Int ; 162(Pt A): 111973, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461288

RESUMO

Edible flowers have been widely consumed fresh in drinks, salads, desserts and salty dishes. This study evaluated the color parameters, chemical composition (phenolics, sugars, organic acids), volatiles compounds and microbiota (bacterial and fungal communities) in edible purple flowers (Torenia fournieri F. Lind.) cultivated in biocompost and traditional organic systems. Torenia flowers cultivated in biocompost had high (p < 0.05) contents of anthocyanins (cyanidin 3,5-diglucoside, delphinidin 3-glucoside), flavonols (quercitin 3-glycoside, myricetin and rutin), sugars (rhamnose and glucose), organic acids (citric and succinic), aldehydes (hexanal, cis-2-hexenal and trans-2-hexenal), and alcohols (trans-2-hexenol and 3-ethyl-4-methylpentan-1-ol). Flowers cultivated in biocompost showed higher (p < 0.05) abundance Cyanobacteria and Basidiomycota bacterial and fungal phyla, respectively, than flowers cultivated in traditional system. The high abundance of Oxyphotobacteria and Dothideomycetes classes, Acetobacterales and Cladosporiales orders, Oxyphotobacteriaceae and Cladosporiaceae families, and Raoultella and Cladosporium genera characterized torenia flowers cultivated in biocompost. The cultivation system influenced the torenia flowers microbiota and composition, primarily due to environmental response and enhanced uptake of nutrients. Our findings indicate that cultivation of torenia using the agroindustrial based-biocompost improves bioactive and volatiles contents in more purple and fruity flavored flowers, rendering flowers more attractive for consumption.


Assuntos
Microbiota , Micobioma , Humanos , Antocianinas , Flores , Açúcares
7.
Nat Commun ; 13(1): 629, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35110564

RESUMO

The largest living rodent, capybara, can efficiently depolymerize and utilize lignocellulosic biomass through microbial symbiotic mechanisms yet elusive. Herein, we elucidate the microbial community composition, enzymatic systems and metabolic pathways involved in the conversion of dietary fibers into short-chain fatty acids, a main energy source for the host. In this microbiota, the unconventional enzymatic machinery from Fibrobacteres seems to drive cellulose degradation, whereas a diverse set of carbohydrate-active enzymes from Bacteroidetes, organized in polysaccharide utilization loci, are accounted to tackle complex hemicelluloses typically found in gramineous and aquatic plants. Exploring the genetic potential of this community, we discover a glycoside hydrolase family of ß-galactosidases (named as GH173), and a carbohydrate-binding module family (named as CBM89) involved in xylan binding that establishes an unprecedented three-dimensional fold among associated modules to carbohydrate-active enzymes. Together, these results demonstrate how the capybara gut microbiota orchestrates the depolymerization and utilization of plant fibers, representing an untapped reservoir of enzymatic mechanisms to overcome the lignocellulose recalcitrance, a central challenge toward a sustainable and bio-based economy.


Assuntos
Microbioma Gastrointestinal , Plantas/metabolismo , Polissacarídeos/metabolismo , Roedores/microbiologia , Animais , Bactérias/classificação , Bactérias/enzimologia , Bactérias/metabolismo , Bacteroidetes/enzimologia , Bacteroidetes/genética , Bacteroidetes/metabolismo , Metabolismo dos Carboidratos , Cristalografia por Raios X , Fibras na Dieta/metabolismo , Glicosídeo Hidrolases/metabolismo , Lignina , Filogenia , Simbiose , Xilanos/metabolismo
8.
Probiotics Antimicrob Proteins ; 14(2): 349-359, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35066820

RESUMO

High-fat diet (HFD) consumption is a risk factor for dyslipidemias, insulin resistance, and arterial hypertension linked with gut dysbiosis. Probiotic administration has been suggested as a safe therapeutic strategy for gut microbiota modulation and treatment and/or prevention of cardiometabolic disorders. Here, we assessed the effects of a potentially probiotic formulation containing strains of the Limosilactobacillus (L.) fermentum 139, 263, and 296 on the cardiometabolic disorders and gut microbiota derangements provoked by the HFD consumption. Male Wistar rats were allocated into control diet (CTL, n = 6), HFD (n = 6), and HFD receiving L. fermentum formulation (HFD-LF, n = 6) groups for 4 weeks. L. fermentum formulation (109 colony-forming unit (CFU)/ml of each strain) was daily administered by oral gavage. After 4-week follow-up, biochemical measurements, blood pressure (BP), heart rate (HR), sympathetic tone, and gut microbiota composition were evaluated. HFD consumption for 4 weeks increased lipid profile, insulin resistance, sympathetic tone, and blood pressure and impaired gut microbiota composition in male rats. Administration of L. fermentum formulation improved the gut microbiota composition, lipid profile, insulin resistance, autonomic dysfunction, and BP in rats fed with a HFD. Administration of a potentially fruit-derived probiotic formulation of L. fermentum strains improved gut microbiota composition and alleviated hyperlipidemia, insulin resistance, and sympathetic hyperactivity and increased BP in rats fed a HFD. Our findings may encourage the development of randomized controlled trials to assess the effects of L. fermentum treatment in subjects with cardiometabolic disorders.


Assuntos
Microbioma Gastrointestinal , Hipertensão , Resistência à Insulina , Limosilactobacillus fermentum , Probióticos , Animais , Dieta Hiperlipídica/efeitos adversos , Frutas , Microbioma Gastrointestinal/fisiologia , Humanos , Lipídeos , Masculino , Ratos , Ratos Wistar
9.
Chemosphere ; 286(Pt 2): 131752, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34426136

RESUMO

Over recent decades, hydrocarbon concentrations have been augmented in soil and water, mainly derived from accidents or operations that input crude oil and petroleum into the environment. Different techniques for remediation have been proposed and used to mitigate oil contamination. Among the available environmental recovery approaches, bioremediation stands out since these hydrocarbon compounds can be used as growth substrates for microorganisms. In turn, microorganisms can play an important role with significant contributions to the stabilization of impacted areas. In this review, we present the current knowledge about responses from natural microbial communities (using DNA barcoding, multiomics, and functional gene markers) and bioremediation experiments (microcosm and mesocosm) conducted in the presence of petroleum and chemical dispersants in different samples, including soil, sediment, and water. Additionally, we present metabolic mechanisms for aerobic/anaerobic hydrocarbon degradation and alternative pathways, as well as a summary of studies showing functional genes and other mechanisms involved in petroleum biodegradation processes.


Assuntos
Microbiota , Poluição por Petróleo , Petróleo , Poluentes do Solo , Biodegradação Ambiental , Hidrocarbonetos , Poluição por Petróleo/análise , Microbiologia do Solo , Poluentes do Solo/análise
10.
Front Microbiol ; 12: 623951, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34135869

RESUMO

This study aimed to investigate the impact of the food matrix (orange juice and yogurt) on the effects of the spore-forming probiotic microorganism Bacillus coagulans GBI-30 6086 in health parameters and gastrointestinal tract (gut) bacterial diversity in Wistar male rats. Rats (n = 48) were randomly distributed into six groups. The groups were the Control (which received sterile distilled water), Juice (which received orange juice), Yogurt (which received yogurt), Probiotic Bacillus (which received B. coagulans GBI-30 6086 in distilled water), Probiotic Juice (which received orange juice with B. coagulans GBI-30 6086), and Probiotic Yogurt (which received yogurt with B. coagulans GBI-30 6086). Each animal belonging to the different groups was treated for 21 days. The daily administration of probiotic juice or probiotic yogurt did not affect the rats' food or body weight. Rats fed with Probiotic Yogurt showed lower glucose and triglycerides levels (p < 0.05) in comparison to the control group (p < 0.05), while no changes in these parameters were observed in the rats fed with Probiotic Juice. Rats fed with Probiotic Yogurt showed a higher gut bacterial diversity than the control group (p < 0.05), and higher abundance (p < 0.05) of Vibrionales, Enterobacteriales, Burkholderiales, Erysipelotrichales, and Bifidobacteriales compared to all other groups. No changes were observed in the expression levels of antioxidant enzymes or heat shock protein 70 of rats fed with probiotic yogurt or probiotic juice. Results reveal that the consumption of yogurt containing B. coagulans GBI-30 6086 decreases triglycerides and glucose levels and positively impacts the gut bacterial ecology in healthy rats. These animal model findings indicate that the matrix also impacts the functionality of foods carrying spore-forming probiotics. Besides, this research indicates that yogurt is also a suitable food carrier of Bacillus coagulans GBI-30 6086.

11.
Food Funct ; 12(12): 5287-5300, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34009228

RESUMO

This study aimed to evaluate the effects of ingestion of live (9 log CFU mL-1) and ultrasound-inactivated (paraprobiotic, 20 kHz, 40 min) Lacticaseibacillus casei 01 cells for 28 days on healthy parameters (biochemical and cardiovascular) and intestinal microbiota (amplicon sequencing of 16S ribosomal RNA) of rats fed a high-fat diet. Twenty-four male Wistar rats were divided into four groups of six animals: CTL (standard diet), HFD (high-fat diet), HFD-LC (high-fat diet and live L. casei), and HFD-ILC (high-fat diet and inactivated L. casei). The administration of live and ultrasound-inactivated L. casei prevented the increase (p < 0.05) in cholesterol levels (total and LDL) and controlled the insulin resistance in rats fed a high-fat diet. Furthermore, it promoted a modulation of the intestinal microbial composition by increasing (p < 0.05) beneficial bacteria (Lachnospiraceae and Ruminoccocaceae) and decreasing (p < 0.05) harmful bacteria (Clostridiaceae, Enterobacteriaceae, and Helicobacteriacea), attenuating the effects promoted by the HFD ingestion. Only live cells could increase (p < 0.05) the HDL-cholesterol, while only inactivated cells caused attenuation (p < 0.05) of the blood pressure. Results show beneficial effects of live and inactivated L. casei 01 and indicate that ultrasound inactivation produces a paraprobiotic with similar or improved health properties compared to live cells.


Assuntos
Sistema Cardiovascular , Dieta Hiperlipídica/efeitos adversos , Microbioma Gastrointestinal/efeitos dos fármacos , Lactobacillaceae/fisiologia , Lactobacillaceae/efeitos da radiação , Ondas Ultrassônicas , Animais , Bactérias/classificação , Bactérias/genética , Peso Corporal , Ingestão de Alimentos , Microbioma Gastrointestinal/genética , Resistência à Insulina , Intestinos/microbiologia , Masculino , Probióticos/farmacologia , RNA Ribossômico 16S , Ratos , Ratos Wistar
12.
Int J Food Sci Nutr ; 72(8): 1057-1070, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33820498

RESUMO

This study investigated the effects of feeding paraprobiotics obtained by six processes [heat, ultrasound, high pH, low pH, irradiation and supercritical carbon dioxide (CO2)] on biochemical parameters and intestinal microbiota of Wistar male rats. Daily administration of paraprobiotics did not affect (p ≥ 0.05) the food intake, body weight, glucose and triglycerides levels, expression of antioxidant enzymes or thermal shock proteins in comparison to the control. Bifidobacterium lactis inactivated by irradiation and supercritical CO2 decreased the total cholesterol levels in serum (p < 0.05). Bifidobacterium lactis inactivated by supercritical CO2 increased the albumin and creatinine levels, while decreased the HDL-cholesterol levels (p < 0.05). Clostridiales (45.6-56%), Bacteroidales (31.9-44.2%) and Lactobacillales (3.9-7.8%) corresponded to the major orders in paraprobiotic groups. The properties of paraprobiotics are dependent on the method of inactivation, the intensity of the method employed and on the strain used.


Assuntos
Microbioma Gastrointestinal , Probióticos , Animais , Peso Corporal , Dióxido de Carbono , Colesterol/sangue , Temperatura Alta , Concentração de Íons de Hidrogênio , Masculino , Radiação , Ratos , Ratos Wistar
13.
Br J Nutr ; 126(12): 1794-1808, 2021 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-33593462

RESUMO

Strenuous physical activity, sleep deprivation and psychological stress are common features of military field training. The present study aimed to evaluate the effects of supplementation with a synbiotic ice cream on salivary IgA, gastrointestinal symptoms, well-being indicators and gut microbiota in young military participants undergoing field training. Sixty-five military completed the study: one group was supplemented for 30 d with synbiotic ice cream containing: 2·1 × 108 CFU/g for Lactobacillus acidophilus LA-5 and 2·7 × 109 CFU/g for Bifidobacterium animalis BB-12 and 2·3 g of inulin in the 60 g of ice cream at manufacture, and the other with a placebo ice cream. Volunteers were evaluated at pre-supplementation (baseline), post-supplementation and after a 5-d military training. Bifidobacterium and Lactobacillus genera were measured in stool samples and both showed a higher differential abundance post-supplementation and training. Salivary IgA and gastrointestinal symptoms decreased at post-training in both groups (P < 0·05; main effect of time); however, supplementation with synbiotic did not mitigate this effect. Tenseness and sleepiness were decreased in the synbiotic-treated group, but not in the placebo group at post-military training (P = 0·01 and 0·009, respectively; group × time effect). The other well-being indicators were not affected by the synbiotic supplementation. In conclusion, 30 d of synbiotic ice cream supplementation containing inulin, L. acidophilus LA-5 and B. animalis BB-12 favourably modulated gut microbiota and improved tenseness and sleepiness in healthy young military undergoing a 5-d field training. These improvements may be relevant to this population as they may influence the decision-making process in an environment of high physical and psychological stress.


Assuntos
Bifidobacterium animalis , Microbioma Gastrointestinal , Sorvetes , Militares , Probióticos , Simbióticos , Método Duplo-Cego , Humanos , Sorvetes/microbiologia
14.
Int J Food Sci Nutr ; 72(6): 781-793, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33487082

RESUMO

This study investigated the effects of consumption of wheat-durum pasta added of Bifidobacterium animalis inactivated by gamma-irradiation (paraprobiotic) on health and gut microbiota of rats. Twenty-one male rats were divided into three groups as follow: control (Control) receiving standard diet; pasta control (PC) receiving diet containing pasta, and paraprobiotic pasta Bifidobacterium-irradiated (PPBI), receiving paraprobiotic pasta. The serum levels of glucose and total cholesterol were reduced (p < 0.05) in PPBI when compared to the Control (p < 0.05). PPBI showed high abundance (p ˂ 0.05) of Firmicutes and Actinobacteria and a lower abundance of Bacteriodes compared to Control and PC. Besides, the PPBI showed high abundance (p ˂ 0.05) of Clostridiales, Lactobacillales; Bifidobacteriales, Bacillales, and Coriobacteriales in comparison to Control. Specific genera such as Bifibacterium, Lactobacillus, Ruminococcus, Allobaculum, and Blautia were more related to PPBI. Findings reveal wheat-durum pasta as a potential vehicle for delivering paraprobiotics B. animalis.


Assuntos
Bifidobacterium animalis , Dieta , Microbioma Gastrointestinal , Probióticos , Animais , Bifidobacterium , Glicemia , Colesterol/sangue , Clostridiales , Ratos , Triticum
16.
Nat Chem Biol ; 16(8): 920-929, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32451508

RESUMO

The fundamental and assorted roles of ß-1,3-glucans in nature are underpinned on diverse chemistry and molecular structures, demanding sophisticated and intricate enzymatic systems for their processing. In this work, the selectivity and modes of action of a glycoside hydrolase family active on ß-1,3-glucans were systematically investigated combining sequence similarity network, phylogeny, X-ray crystallography, enzyme kinetics, mutagenesis and molecular dynamics. This family exhibits a minimalist and versatile (α/ß)-barrel scaffold, which can harbor distinguishing exo or endo modes of action, including an ancillary-binding site for the anchoring of triple-helical ß-1,3-glucans. The substrate binding occurs via a hydrophobic knuckle complementary to the canonical curved conformation of ß-1,3-glucans or through a substrate conformational change imposed by the active-site topology of some fungal enzymes. Together, these findings expand our understanding of the enzymatic arsenal of bacteria and fungi for the breakdown and modification of ß-1,3-glucans, which can be exploited for biotechnological applications.


Assuntos
Glucana 1,3-beta-Glucosidase/química , Glicosídeo Hidrolases/química , beta-Glucanas/química , Sequência de Aminoácidos/genética , Sítios de Ligação/fisiologia , Domínio Catalítico/fisiologia , Cristalografia por Raios X/métodos , Glucana 1,3-beta-Glucosidase/metabolismo , Glucanos/química , Glicosídeos/química , Modelos Moleculares , Especificidade por Substrato/fisiologia
17.
Br J Nutr ; : 1-12, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32138793

RESUMO

The aim of the present work was to compare the capacity to modulate the intestinal microbiota and the production of metabolites after 14 d administration of a commercial dietary supplement and a manufactured ice cream, both containing the same quantity of inulin and the same viable counts of Lactobacillus acidophilus LA-5 and Bifidobacterium animalis BB-12, using the Simulator of the Human Intestinal Microbial Ecosystem (SHIME®) model. Samples of the colonic contents were evaluated microbiologically by real-time quantitative PCR (qRT-PCR) and next-generation sequencing and chemically by the production of SCFA (acetate, propionate and butyrate) and ammonium ions ($\text{NH}_4^ + $). Statistical analyses were carried out for all the variables using the two-way ANOVA followed by the Tukey multiple comparisons test (P < 0·05) for metabolite production, qRT-PCR and the bioinformatics analysis for microbiota diversity. Dietary supplement and ice cream were able to deliver the probiotic L. acidophilus and B. animalis to the simulated colon and modulate the microbiota, increasing beneficial micro-organisms such as Bifidobacterium spp., Bacteroides spp. and Faecalibacterium spp. for dietary supplement administration, and Lactobacillus spp. for ice cream supplementation. However, the ice cream matrix was probably more favourable for the maintenance of the metabolic activity of the probiotics in the SHIME® model, due to the larger amounts of acetate, propionate, butyrate and ammonium ions obtained after 14 d of supplementation. In conclusion, both ways of probiotic supplementation could be efficient, each with its own particularities.

18.
Food Microbiol ; 89: 103453, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32138999

RESUMO

In this work, the amplicon sequencing of the 16 S rRNA gene was employed to investigate the bacterial diversity in ingredients, processing environment, and ripened cheeses collected from three farms producing Serra da Canastra artisanal cheese. The data obtained indicated a remarkable variability in the bacteria consortia of the milk, whey, and environmental samples collected in farms 1, 2, and 3, despite their location in the same city. On the other hand, the starter culture and final product (ripened cheese) presented more constant and similar microbiota no matter the farm. The findings suggest that Streptococcus and Lactococcus have competitive advantages throughout Serra da Canastra cheese-making/ripening, which is crucial for their high relative abundance in the final products. An exploratory assessment based on sequencing data available in the literature showed that the Serra da Canastra cheeses sequences clustered with specific cheese varieties that are also made from raw milk but ripened for very different periods. The findings of this study highlight that despite the variability of milk and whey microbiota among the three farms, the starter culture ("pingo") has strong relevance in shaping the microbiota of the final product.


Assuntos
Bactérias/classificação , Queijo/microbiologia , Microbiota , Leite/microbiologia , Animais , Fazendas , Microbiologia de Alimentos , RNA Ribossômico 16S/genética
19.
J Proteomics ; 212: 103549, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-31698103

RESUMO

Vertebrates usually have three class V myosin paralogues (MyoV) to control membrane trafficking in the actin-rich cell cortex, but their functional overlapping or differentiation through cargoes selectivity is yet only partially understood. In this work, we reveal that the globular tail domain of MyoVc binds to the active form of small GTPase Rab3A with nanomolar affinity, a feature shared with MyoVa but not with MyoVb. Using molecular docking analyses guided by chemical cross-linking restraints, we propose a model to explain how Rab3A selectively recognizes MyoVa and MyoVc via a distinct binding site from that used by Rab11A. The MyoVa/c binding interface involves multiple residues from both lobules (I and II) and the short helix at the α2-α3 link region, which is conserved between MyoVa and MyoVc, but not in MyoVb. This motif is also responsible for the selective binding of RILPL2 by MyoVa and potentially MyoVc. Together, these findings support the selective recruitment of MyoVa and MyoVc to exocytic pathways via Rab3A and expand our knowledge about the functional evolution of class V myosins. SIGNIFICANCE: Hormone secretion, neurotransmitter release, and cytoplasm membrane recycling are examples of processes that rely on the interaction of molecular motors and Rab GTPases to regulate the intracellular trafficking and tethering of vesicles. Defects in these proteins may cause neurological impairment, immunodeficiency, and other severe disorders, being fatal in some cases. Despite their crucial roles, little is known about how these molecular motors are selectively recruited by specific members of the large family of Rab GTPases. In this study, we unveil the interaction between the actin-based molecular motor Myosin Vc and the small GTPase Rab3A, a key coordinator of vesicle trafficking and exocytosis in mammalian cells. Moreover, we propose a model for their recognition and demonstrate that Rab3A specifically binds to the globular tail of Myosins Va and Vc, but not of Myosin Vb, advancing our knowledge about the molecular basis for the selective recruitment of class V myosins by Rab GTPases.


Assuntos
Exocitose , Miosina Tipo V/química , Proteína rab3A de Ligação ao GTP/química , Actinas/metabolismo , Animais , Transporte Biológico , Linhagem Celular , Haplorrinos , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular/métodos , Miosina Tipo V/isolamento & purificação , Miosina Tipo V/metabolismo , Ligação Proteica , Homologia de Sequência de Aminoácidos , Proteína rab3A de Ligação ao GTP/isolamento & purificação , Proteína rab3A de Ligação ao GTP/metabolismo
20.
Front Microbiol ; 10: 648, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31024471

RESUMO

Drylands occupy approximately 41% of the Earth's terrestrial surface. Climate change and land use practices are expected to affect biogeochemical cycling by the soil microbiome in these ecosystems. Understanding how soil microbial community might respond to these drivers is extremely important to mitigate the processes of land degradation and desertification. The Caatinga, an exclusively Brazilian biome composed of an extensive seasonal tropical dry forest, is exposed to variable spatiotemporal rainfall patterns as well as strong human-driven pressures. Herein, an integrated analysis of shotgun metagenomics approach coupled to meteorological data was employed to unravel the impact of seasonality and land use change on soil microbiome from preserved and agriculture-affected experimental fields in Caatinga drylands. Multivariate analysis suggested that microbial communities of preserved soils under seasonal changes were shaped primarily by water deficit, with a strong increase of Actinobacteria and Proteobacteria members in the dry and rainy seasons, respectively. In contrast, nutrient availability notably played a critical role in driving the microbial community in agriculture-affected soils. The strong enrichment of bacterial genera belonging to the poorly-known phylum Acidobacteria ('Candidatus Solibacter' and 'Candidatus Koribacter') in soils from dry season affected by ferti-irrigation practices presupposes a contrasting copiotrophic lifestyle and ecological role in mitigating the impact of chemical fertilization. Functional analyses identify overrepresented genes related to osmotic stress response (synthesis of osmoprotectant compounds, accumulation of potassium ions) and preferential carbon and nitrogen utilization when comparing the microbiome of preserved soils under seasonal changes, reflecting differences in the genetic potential for nutrient cycling and C acquisition in the environment. However, the prevalence of nitrosative stress and denitrification functions in irrigation/fertilization-affected soils of the dry season clearly suggest that nutrient input and disruption of natural water regime may impact biogeochemical cycles linked to the microbial processes, with potential impacts on the ecosystem functionality. These findings help to better understand how natural seasonality and agricultural management differentially affect soil microbial ecology from dry forests, providing support for the development of more sustainable land management in dryland ecosystems.

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