Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 5.146
Filtrar
1.
Food Chem ; 370: 131370, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34662797

RESUMO

In this study, stationary and time-resolvedfluorescence signatures, were statistically and chemometrically analyzed among three typologies of Chardonnay wines (A, B and C) with the objectives to evaluate their sensitivity to acidic and polyphenolic changes. For that purpose, a dataset was built using Excitation Emission Matrices of fluorescence (N = 103) decomposed by a Parallel Factor Analysis (PARAFAC), andfluorescence decays (N = 22), mathematically fitted, using the conventional exponential modeling and the phasor plot representation. Wine PARAFAC component C4 coupledwith its phasor plot g and s values enable the description of malolactic fermentation (MLF) occurrence in Chardonnay wines. Such proxies reflect wine concentration modifications in total acidity, malic/lactic and phenol acids.Lower g values among fresh MLF + wines compared to MLF- wines are explained by a quenching effect on wine fluorophores by both organic and phenolic acids.The combination of multispectral fluorescence parametersopens a novel routinely implementable methodology to diagnose fermentative processes.


Assuntos
Vinho , Fermentação , Fluorescência , Malatos , Vinho/análise
2.
Trop Anim Health Prod ; 53(5): 514, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34643791

RESUMO

Dietary strategies aiming at minimizing enteric methane (CH4) emission in ruminants are of practical interest from nutritional, economical, and environmental point of view. The present study evaluated the effects of supplementing Leucaena leucocephala leaves either alone or in conjunction with malic acid on nutrient utilization, growth performance, and enteric CH4 emission in crossbred cattle fed wheat straw and concentrate-based diet under tropical conditions. Eighteen crossbred (Karan-Fries) calves were randomly allocated into 3 groups: G-I (control)-fed wheat (Triticum aestivum) straw and concentrate mixture in the ratio 50:50; G-II-fed wheat straw, concentrate mixture, and Leucaena leucocephala leaves in the ratio 45:45:10; and (3) G-III-fed similar diet like G-II with an additional supplementation of 1% malic acid on dry matter intake basis. Experimental feeding spanning 90 days included a 7-day metabolism trial and CH4 quantification study by sulfur hexafluoride tracer technique. Results revealed no significant effect of dietary treatments on dry matter intake (DMI) and digestibility of nutrients, except neutral detergent fiber (NDF) digestibility which was 5.5% higher (P < 0.05) in G-III as compared to control. Further, nitrogen (N) metabolism, rumen microbial protein synthesis, and growth performance remained similar among the treatments. No significant effect was also observed for enteric CH4 emission (expressed as g/day and g/kg DMI) in calves supplemented with Leucaena leucocephala leaves and malic acid. Therefore, the present findings depict modest improvement in fiber digestibility with no encouraging effect in mitigating enteric CH4 in growing cattle calves by supplementing Leucaena leucocephala leaves alone or with malic acid within the selected levels.


Assuntos
Digestão , Metano , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Fermentação , Malatos , Metano/metabolismo , Nutrientes , Folhas de Planta , Rúmen/metabolismo , Clima Tropical
3.
Bioresour Technol ; 341: 125897, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34523561

RESUMO

Camellia oleifera shell (COS), a by-product of processing woody vegetable oil, is rich in hemicellulose and lignin. In this study, we investigated the effects of acid concentration, pretreatment temperature and reaction time on the concentration and yield of xylo-oligosaccharides (XOS) and the degree of polymerization (DP) distribution of XOS when pretreating COS with malic acid (MA). Under moderate condition (2 M MA, 120 â„ƒ, 30 min), the maximum yield of XOS with DP 2-4 was 48.78% (based on the initial xylan) with low xylose, 5-hydroxymethylfurfural (HMF) and furfural, in which xylobiose (X2), xylotriose (X3) and xylotraose (X4) concentrations were 5.22 g/L, 2.75 g/L and 2.91 g/L, respectively. In addition, acid-insoluble lignin (AIL) in the residue after MA pretreatment and milling wood lignin (MWL) were mainly composed of guaiacyl and syringyl. AIL has higher thermal stability than MWL, which can be the stabilizer for producing flame-resistant materials.


Assuntos
Camellia , Lignina , Hidrólise , Malatos , Oligossacarídeos
4.
Int J Food Microbiol ; 356: 109324, 2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34474175

RESUMO

Previously six selected Oenococcus oeni strains (P2A, P3A, P3G, P5A, P5C and P7B) have been submitted to further characterization in order to clarify their potential as malolactic starters. Laboratory scale vinifications gave an insight of the most vigorous strains: both P2A and P3A strains were able to conclude malolactic fermentation (MLF) in less than 15 days. The remaining strains showed good viability and were able to successfully finish MLF in the established analysis time, except for the strain P5A, which viability was totally lost after inoculation. Also spontaneous fermentation was not initiated. None of the strains was biogenic amine producer; however, P5C strain significantly increased the concentration of volatile phenol-precursor hydroxycinnamic acids after MLF. Regarding the evolution of wine aromatic compounds, main changes were detected for both ethyl and acetate esters after MLF; however, key aromatic compounds including alcohols, terpenes or acids were also found to significantly increase. Principal component analysis classified the strains in two distinct groups, each one correlated with different key volatile compounds. P2A, P3A, P3G and P5C strains were mainly linked to esters, while P7B and the commercial strain Viniflora OENOS showed higher score for diverse compounds as hexanoic acid, ß-damascenone, linalool or 2-phenylethanol. These results confirmed the specific impact of each strain on wine aroma profile, which could lead to the production of wines with individual characteristics, in which the reliability and safety of MLF is also ensured.


Assuntos
Odorantes , Oenococcus , Vinho , Fermentação , Malatos/metabolismo , Odorantes/análise , Oenococcus/metabolismo , Vinho/análise , Vinho/microbiologia
5.
Int J Mol Sci ; 22(17)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34502530

RESUMO

Fruit acidity is one of the main determinants of fruit flavor and a target trait in fruit breeding. However, the genomic mechanisms governing acidity variation among different pear varieties remain poorly understood. In this study, two pear varieties with contrasting organic acid levels, 'Dangshansuli' (low-acidity) and 'Amute' (high-acidity), were selected, and a combination of transcriptome and population genomics analyses were applied to characterize their patterns of gene expression and genetic variation. Based on RNA-seq data analysis, differentially expressed genes (DEGs) involved in organic acid metabolism and accumulation were identified. Weighted correlation network analysis (WGCNA) revealed that nine candidate TCA (tricarboxylic acid)-related DEGs and three acid transporter-related DEGs were located in three key modules. The regulatory networks of the above candidate genes were also predicted. By integrating pear resequencing data, two domestication-related genes were found to be upregulated in 'Amute', and this trend was further validated for other pear varieties with high levels of organic acid, suggesting distinct selective sweeps during pear dissemination and domestication. Collectively, this study provides insight into organic acid differences related to expression divergence and domestication in two pear varieties, pinpointing several candidate genes for the genetic manipulation of acidity in pears.


Assuntos
Ácidos Carboxílicos/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Pyrus/genética , RNA-Seq/métodos , Transcriptoma/genética , Ácido Cítrico/metabolismo , Frutas/genética , Frutas/metabolismo , Ontologia Genética , Redes Reguladoras de Genes , Malatos/metabolismo , Ácido Oxálico/metabolismo , Filogenia , Pyrus/classificação , Pyrus/metabolismo , Especificidade da Espécie
6.
Molecules ; 26(17)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34500843

RESUMO

Primary cilia mediate the interactions between cells and external stresses. Thus, dysregulation of primary cilia is implicated in various ciliopathies, e.g., degeneration of the retina caused by dysregulation of the photoreceptor primary cilium. Particulate matter (PM) can cause epithelium injury and endothelial dysfunction by increasing oxidative stress and inflammatory responses. Previously, we showed that PM disrupts the formation of primary cilia in retinal pigment epithelium (RPE) cells. In the present study, we identified 2-isopropylmalic acid (2-IPMA) as a novel inducer of primary ciliogenesis from a metabolite library screening. Both ciliated cells and primary cilium length were increased in 2-IPMA-treated RPE cells. Notably, 2-IPMA strongly promoted primary ciliogenesis and restored PM2.5-induced dysgenesis of primary cilia in RPE cells. Both excessive reactive oxygen species (ROS) generation and activation of a stress kinase, JNK, by PM2.5 were reduced by 2-IPMA. Moreover, 2-IPMA inhibited proinflammatory cytokine production, i.e., IL-6 and TNF-α, induced by PM2.5 in RPE cells. Taken together, our data suggest that 2-IPMA ameliorates PM2.5-induced inflammation by promoting primary ciliogenesis in RPE cells.


Assuntos
Inflamação/metabolismo , Material Particulado/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Cílios/metabolismo , Cílios/ultraestrutura , Citocinas/metabolismo , Ativação Enzimática , Técnicas de Silenciamento de Genes , Humanos , MAP Quinase Quinase 4/metabolismo , Malatos/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Retina
7.
Int J Mol Sci ; 22(15)2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34360597

RESUMO

Toxoplasma gondii is a protozoan parasite that causes toxoplasmosis and infects almost one-third of the global human population. A lack of effective drugs and vaccines and the emergence of drug resistant parasites highlight the need for the development of new drugs. The mitochondrial electron transport chain (ETC) is an essential pathway for energy metabolism and the survival of T. gondii. In apicomplexan parasites, malate:quinone oxidoreductase (MQO) is a monotopic membrane protein belonging to the ETC and a key member of the tricarboxylic acid cycle, and has recently been suggested to play a role in the fumarate cycle, which is required for the cytosolic purine salvage pathway. In T. gondii, a putative MQO (TgMQO) is expressed in tachyzoite and bradyzoite stages and is considered to be a potential drug target since its orthologue is not conserved in mammalian hosts. As a first step towards the evaluation of TgMQO as a drug target candidate, in this study, we developed a new expression system for TgMQO in FN102(DE3)TAO, a strain deficient in respiratory cytochromes and dependent on an alternative oxidase. This system allowed, for the first time, the expression and purification of a mitochondrial MQO family enzyme, which was used for steady-state kinetics and substrate specificity analyses. Ferulenol, the only known MQO inhibitor, also inhibited TgMQO at IC50 of 0.822 µM, and displayed different inhibition kinetics compared to Plasmodium falciparum MQO. Furthermore, our analysis indicated the presence of a third binding site for ferulenol that is distinct from the ubiquinone and malate sites.


Assuntos
Cumarínicos/metabolismo , Malatos/metabolismo , Proteínas Mitocondriais/metabolismo , Oxirredutases/metabolismo , Proteínas de Protozoários/metabolismo , Toxoplasma/enzimologia , Ubiquinona/metabolismo , Animais , Humanos , Proteínas Mitocondriais/genética , Oxirredutases/genética , Proteínas de Protozoários/genética , Especificidade por Substrato
8.
J Agric Food Chem ; 69(33): 9632-9641, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34428900

RESUMO

Malate as an important intermediate metabolite, its subcellular location, and concentration have a significant impact on fungal lipid metabolism. Previous studies showed that the mitochondrial malate transporter plays an important role in lipid accumulation in Mucor circinelloides by manipulating intracellular malate concentration. However, the role of plasma membrane malate transporters in oleaginous fungi remains unexplored. Therefore, in this work, two plasma membrane malate transporters "2-oxoglutarate:malate antiporters" (named SoDIT-a and SoDIT-b) of M. circinelloides WJ11 were deleted, and the consequences in growth capacity, lipid accumulation, and metabolism were analyzed. The results showed that deletion of sodit-a or/and sodit-b reduced the extracellular malate, confirming that the products of both genes participate in malate transportation. In parallel, the lipid contents in mutants increased approximately 10-40% higher than that in the control strain, suggesting that the defect in plasma membrane malate transport results in an increase of malate available for lipid biosynthesis. Furthermore, transcriptional analysis showed that the expression levels of multiple key genes involved in the lipid biosynthesis were also increased in the knockout mutants. To the best of our knowledge, this is the first report that demonstrated the association between plasma membrane malate transporters and lipid accumulation in M. circinelloides.


Assuntos
Malatos , Mucor , Membrana Celular , Lipídeos , Proteínas de Membrana Transportadoras , Mucor/genética
9.
Food Microbiol ; 100: 103854, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34416957

RESUMO

This study investigated the effects of combinations of acetic or malic acid and various solutes (salt, glucose, glycine, or sucrose) on the survival of Escherichia coli O157:H7 in laboratory broth. Additionally, the effectiveness of combining organic acids and various concentrations of salt (0-18%) or sucrose (0-100%) with different water activity values against E. coli O157:H7 were evaluated. For treatment of 1% malic acid, the addition of 3% salt showed synergistic effect. Whereas, when 3% salt, glucose, glycine, or sucrose was added to 1% acetic acid, the solutes antagonized the action of the acid against E. coli O157:H7. Acetic, lactic, or propionic acid combined with salt at either 7 or 9% or sucrose at 60, 80, or 100% resulted in the highest resistance of E. coli O157:H7. From a result of evaluating the membrane fatty acid (MFA) composition of cells, salt or sucrose significantly increased levels of saturated fatty acids (SFAs) or SFAs and cyclopropane fatty acids, respectively. From the results of this study, the addition of solutes and organic compounds may increase the tolerance of E. coli O157:H7 to acetic, lactic, and propionic acid treatments and that the salt or sucrose significantly affects cell MFA composition.


Assuntos
Ácido Acético/farmacologia , Escherichia coli O157/efeitos dos fármacos , Escherichia coli O157/crescimento & desenvolvimento , Glucose/metabolismo , Malatos/farmacologia , Propionatos/farmacologia , Cloreto de Sódio/metabolismo , Sacarose/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Meios de Cultura/química , Meios de Cultura/metabolismo , Escherichia coli O157/metabolismo , Ácidos Graxos/metabolismo , Glicina/metabolismo
10.
PLoS One ; 16(7): e0254583, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34265023

RESUMO

In this experiment, response surface methodology was used to study the preparation of malic acid calcium salt from bovine bones assisted by ultrasonication. The results showed that the optimum conditions for ultrasound-assisted preparation of calcium malate from bovine bone were as follows: solid-liquid ratio 1:15, solid-acid ratio 1:1.5, ultrasonic power 200 W, ultrasonic temperature 35°C, and ultrasonication time 17 min. The efficiency of calcium recovery was 66.16%, and the purity was 92.54%. After three ultrasonic treatments of 17 min each, the calcium malate conversion rate of bovine bone reached 95.73%. Animal experiments showed that feeding bovine bone-derived calcium malate significantly increased alkaline phosphatase (ALP) activity and bone calcium content, reduced tartrate-resistant acid phosphatase (TRAP) activity, and maintained the balance of serum calcium and phosphorus. These results indicated that the ultrasonic method effectively ionized calcium in bovine bone, which provides a reference point for the industrial production of calcium products with bovine bone as the raw material.


Assuntos
Cálcio , Malatos , Animais , Osso e Ossos , Bovinos , Fosfatase Ácida Resistente a Tartarato
11.
Bioresour Technol ; 337: 125443, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34171705

RESUMO

Cheese whey is an abundant and low-cost feedstock with lactose as its main component, but the inability to metabolize lactose prevents Aureobasidium pullulans from using cheese whey directly. In this study, Kluyveromyces marxianus was permeabilized to obtain nonviable but biocatalytic cells for lactose hydrolysis, and the mixed culture of A. pullulans and permeabilized K. marxianus was conducted for polymalic acid (PMA) production from cheese whey. In the mixed culture, PMA titer varied directly to ß-galactosidase activity of K. marxianus, but inversely to cell viability of K. marxianus, and ethanol permeabilized K. marxianus was the most compatible with A. pullulans for PMA production. 37.8 g/L PMA was produced in batch fermentation, and PMA titer was increased to 97.3 g/L in fed-batch fermentation, with a productivity of 0.51 g/(L·h) and a yield of 0.56 g/g. This study paved an economical and environmentally friendly way for PMA production from cheese whey.


Assuntos
Queijo , Kluyveromyces , Aureobasidium , Fermentação , Glucanos , Lactose , Malatos , Polímeros , Soro do Leite
12.
Commun Biol ; 4(1): 725, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34117367

RESUMO

Methionine metabolism arises as a key target to elucidate the molecular adaptations underlying animal longevity due to the negative association between longevity and methionine content. The present study follows a comparative approach to analyse plasma methionine metabolic profile using a LC-MS/MS platform from 11 mammalian species with a longevity ranging from 3.5 to 120 years. Our findings demonstrate the existence of a species-specific plasma profile for methionine metabolism associated with longevity characterised by: i) reduced methionine, cystathionine and choline; ii) increased non-polar amino acids; iii) reduced succinate and malate; and iv) increased carnitine. Our results support the existence of plasma longevity features that might respond to an optimised energetic metabolism and intracellular structures found in long-lived species.


Assuntos
Longevidade/fisiologia , Metionina/sangue , Animais , Carnitina/metabolismo , Gatos , Bovinos , Colina/sangue , Colina/metabolismo , Colina/fisiologia , Cistationina/sangue , Cistationina/metabolismo , Cistationina/fisiologia , Cães , Cromatografia Gasosa-Espectrometria de Massas , Cobaias , Cavalos , Humanos , Malatos/sangue , Malatos/metabolismo , Metionina/metabolismo , Metionina/fisiologia , Camundongos , Filogenia , Coelhos , Ratos , Ovinos , Ácido Succínico/sangue , Ácido Succínico/metabolismo , Suínos
13.
Molecules ; 26(9)2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-34066468

RESUMO

NR+ is a highly effective vitamin B3 type supplement due to its unique ability to replenish NAD+ levels. While NR+ chloride is already on the market as a nutritional supplement, its synthesis is challenging, expensive, and low yielding, making it cumbersome for large-scale industrial production. Here we report the novel crystalline NR+ salts, d/l/dl-hydrogen tartrate and d/l/dl-hydrogen malate. Their high-yielding, one-pot manufacture does not require specific equipment and is suitable for multi-ton scale production. These new NR+ salts seem ideal for nutritional applications due to their bio-equivalence compared to the approved NR+ chloride. In addition, the crystal structures of all stereoisomers of NR+ hydrogen tartrate and NR+ hydrogen malate and a comparison to the known NR+ halogenides are presented.


Assuntos
Aditivos Alimentares/química , Tecnologia de Alimentos/métodos , Niacinamida/análogos & derivados , Niacinamida/química , Compostos de Piridínio/química , Ânions , Técnicas de Química Sintética , Cloretos , Cristalização , Suplementos Nutricionais , Hidrogênio/química , Espectroscopia de Ressonância Magnética , Malatos/química , Oxirredução , Sais , Estereoisomerismo , Tartaratos/química , Difração de Raios X
14.
Appl Microbiol Biotechnol ; 105(12): 5053-5066, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34106310

RESUMO

The two most commonly used wine microorganisms, Saccharomyces cerevisiae yeast and Oenococcus oeni bacteria, are responsible for completion of alcoholic and malolactic fermentation (MLF), respectively. For successful co-inoculation, S. cerevisiae and O. oeni must be able to complete fermentation; however, this relies on compatibility between yeast and bacterial strains. For the first time, quantitative trait loci (QTL) analysis was used to elucidate whether S. cerevisiae genetic makeup can play a role in the ability of O. oeni to complete MLF. Assessment of 67 progeny from a hybrid S. cerevisiae strain (SBxGN), co-inoculated with a single O. oeni strain, SB3, revealed a major QTL linked to MLF completion by O. oeni. This QTL encompassed a well-known translocation, XV-t-XVI, that results in increased SSU1 expression and is functionally linked with numerous phenotypes including lag phase duration and sulphite export and production. A reciprocal hemizygosity assay was performed to elucidate the effect of the gene SSU1 in the SBxGN background. Our results revealed a strong effect of SSU1 haploinsufficiency on O. oeni's ability to complete malolactic fermentation during co-inoculation and pave the way for the implementation of QTL mapping projects for deciphering the genetic bases of microbial interactions. KEY POINTS: • For the first time, QTL analysis has been used to study yeast-bacteria interactions. • A QTL encompassing a translocation, XV-t-XVI, was linked to MLF outcomes. • S. cerevisiae SSU1 haploinsufficiency positively impacted MLF by O. oeni.


Assuntos
Oenococcus , Vinho , Fermentação , Determinismo Genético , Malatos , Locos de Características Quantitativas , Saccharomyces cerevisiae/genética , Vinho/análise
15.
Nat Commun ; 12(1): 3730, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140480

RESUMO

Acid taste, evoked mainly by protons (H+), is a core taste modality for many organisms. The hedonic valence of acid taste is bidirectional: animals prefer slightly but avoid highly acidic foods. However, how animals discriminate low from high acidity remains poorly understood. To explore the taste perception of acid, we use the fruit fly as a model organism. We find that flies employ two competing taste sensory pathways to detect low and high acidity, and the relative degree of activation of each determines either attractive or aversive responses. Moreover, we establish one member of the fly Otopetrin family, Otopetrin-like a (OtopLa), as a proton channel dedicated to the gustatory detection of acid. OtopLa defines a unique subset of gustatory receptor neurons and is selectively required for attractive rather than aversive taste responses. Loss of otopla causes flies to reject normally attractive low-acid foods. Therefore, the identification of OtopLa as a low-acid sensor firmly supports our competition model of acid taste sensation. Altogether, we have discovered a binary acid-sensing mechanism that may be evolutionarily conserved between insects and mammals.


Assuntos
Ácidos/metabolismo , Vias Aferentes/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Neurônios/metabolismo , Vias Aferentes/fisiologia , Animais , Animais Geneticamente Modificados , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Eletrofisiologia , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio , Imuno-Histoquímica , Malatos/metabolismo , Microscopia Confocal , Mutação , Neurônios/fisiologia , Receptores de Superfície Celular/metabolismo , Proteínas Recombinantes , Paladar/fisiologia , Percepção Gustatória/fisiologia
16.
Food Microbiol ; 99: 103839, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119090

RESUMO

The use of non-Saccharomyces yeast together with S. cerevisiae in winemaking is a current trend. Apart from the organoleptic modulation of the wine, the composition of the resulting yeast lees is different and may thus impact malolactic fermentation (MLF). Yeasts of Saccharomyces cerevisiae, Torulaspora delbrueckii and Metschnikowia pulcherrima were inactivated and added to a synthetic wine. Three different strains of Oenococcus oeni were inoculated and MLF was monitored. Non-Saccharomyces lees, especially from some strains of T. delbrueckii, showed higher compatibility with some O. oeni strains, with a shorter MLF and a maintained bacterial cell viability. The supplementation of lees increased nitrogen compounds available by O. oeni. A lower mannoprotein consumption was related with longer MLF. Amino acid assimilation by O. oeni was strain specific. There may be many other compounds regulating these yeast lees-O. oeni interactions apart from the well-known mannoproteins and amino acids. This is the first study of MLF with different O. oeni strains in the presence of S. cerevisiae and non-Saccharomyces yeast lees to report a strain-specific interaction between them.


Assuntos
Malatos/metabolismo , Oenococcus/metabolismo , Vinho/microbiologia , Leveduras/metabolismo , Meios de Cultura/metabolismo , Fermentação , Filogenia , Leveduras/classificação , Leveduras/genética
17.
World J Microbiol Biotechnol ; 37(7): 115, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34125306

RESUMO

The aim of this work was to obtain freeze-dried biomass of the native Patagonian Lactiplantibacillus plantarum strain UNQLp 11 from a whey permeate (WP)-based medium and compare it with the growth in commercial MRS broth medium. Survival and activity of the freeze-dried Lb. plantarum strain were investigated after inoculation in wine as a starter culture for malolactic fermentation (MLF). The effect of storage and rehydration condition of the dried bacteria and the nutrient supplementation of wine were also studied. The freeze-dried cultures from WP and those grown in MRS showed similar survival results. Rehydration in MRS broth for 24 h and the addition of a rehydration medium to wine as nutrient supplementation improved the survival under wine harsh conditions and guaranteed the success of MLF. Storage at 4 °C under vacuum was the best option, maintaining high cell viability for at least 56 days, with malic acid consumption higher than 90% after 7 days of inoculation in a wine-like medium. These results represent a significant advance for sustainable production of dried malolactic starter cultures in an environmentally friendly process, which is low cost and easy to apply in winemaking under harsh physicochemical conditions.


Assuntos
Meios de Cultura/química , Lactobacillus plantarum/crescimento & desenvolvimento , Malatos/química , Soro do Leite/química , Vinho/microbiologia , Técnicas Bacteriológicas , Biomassa , Fermentação , Microbiologia de Alimentos , Liofilização , Lactobacillus plantarum/química , Lactobacillus plantarum/isolamento & purificação , Viabilidade Microbiana
18.
Sci Rep ; 11(1): 12674, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34135458

RESUMO

In our previous work, we reported a novel approach for increasing lipid production in an oleaginous fungus Mucor circinelloides by overexpression of mitochondrial malate transporter protein. This transporter plays a vital role in fatty acid biosynthesis during malate and citrate transport systems in oleaginous fungi. In this study, the controlling metabolic supplementation strategy was used to improve the lipid production by overexpression of malate transporter protein in M. circinelloides strain coded as Mc-MT-2. The effects of different metabolic intermediates on lipid production in batch fermentation by Mc-MT-2 were investigated. The optimal lipid production was obtained at 0.8% malic acid after 24 h of fermentation. Furthermore, in fed-batch bioreactors containing glucose as a carbon source supplemented with malic acid, the highest cell growth, and lipid production were achieved. The resulting strain showed the fungal dry biomass of 16 g/L, a lipid content of 32%, lipid yield of 5.12 g/L in a controlled bench-top bioreactor, with 1.60-, 1.60- and 2.56-fold improvement, respectively, compared with the batch control without supplementation of malic acid. Our findings revealed that the addition of malic acid during fermentation might play an important role in lipid accumulation in the recombinant M. circinelloides Mc-MT-2. This study provides valuable insights for enhanced microbial lipid production through metabolic supplementation strategy in large scale and industrial applications.


Assuntos
Metabolismo dos Lipídeos , Malatos/metabolismo , Mucor/metabolismo , Reatores Biológicos , Meios de Cultura , Fermentação , Proteínas Fúngicas/metabolismo , Glucose/metabolismo , Mucor/genética , Mucor/crescimento & desenvolvimento , Transportadores de Ânions Orgânicos/genética , Transportadores de Ânions Orgânicos/metabolismo
19.
Int J Sport Nutr Exerc Metab ; 31(4): 350-358, 2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34010809

RESUMO

Citrulline malate (CitMal) is a dietary supplement that is suggested to enhance strength training performance. However, there is conflicting evidence on this matter. Thus, the purpose of this meta-analysis was to determine whether supplementing with CitMal prior to strength training could increase the total number of repetitions performed before reaching voluntary muscular failure. A systematic search was conducted wherein the inclusion criteria were double-blind, placebo-controlled studies in healthy participants that examined the effect of CitMal on repetitions to failure during upper body and lower body resistance exercises. The Hedges's g standardized mean differences (SMD) between the placebo and CitMal trials were calculated and used in a random effect model. Two separate subanalyses were performed for upper body and lower body exercises. Eight studies, including 137 participants who consisted of strength-trained men (n = 101) and women (n = 26) in addition to untrained men (n = 9), fulfilled the inclusion criteria. Across the studies, 14 single-joint and multijoint exercises were performed with an average of 51 ± 23 total repetitions during 5 ± 3 sets per exercise at ∼70% of one-repetition maximum. Supplementing with 6-8 g of CitMal 40-60 min before exercise increased repetitions by 3 ± 5 (6.4 ± 7.9%) compared with placebo (p = .022) with a small SMD (0.196). The subanalysis for the lower body resulted in a tendency for an effect of the supplement (8.1 ± 8.4%, SMD: 0.27, p = .051) with no significant effect for the upper body (5.7 ± 8.4%, SMD: 0.16, p = .131). The current analysis observed a small ergogenic effect of CitMal compared with placebo. Acute CitMal supplementation may, therefore, delay fatigue and enhance muscle endurance during high-intensity strength training.


Assuntos
Citrulina/análogos & derivados , Malatos/farmacologia , Substâncias para Melhoria do Desempenho/farmacologia , Resistência Física/efeitos dos fármacos , Desempenho Físico Funcional , Treinamento de Força/métodos , Adulto , Viés , Citrulina/administração & dosagem , Citrulina/farmacologia , Método Duplo-Cego , Feminino , Humanos , Malatos/administração & dosagem , Masculino , Resistência Física/fisiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo , Adulto Jovem
20.
Int J Mol Sci ; 22(9)2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33924853

RESUMO

Low phosphorus (P) availability is one of the major constraints to plant growth, particularly in acidic soils. A possible mechanism for enhancing the use of sparsely soluble P forms is the secretion of malate in plants by the aluminum-activated malate transporter (ALMT) gene family. Despite its significance in plant biology, the identification of the ALMT gene family in oilseed rape (Brassica napus; B. napus), an allotetraploid crop, is unveiled. Herein, we performed genome-wide identification and characterization of ALMTs in B. napus, determined their gene expression in different tissues and monitored transcriptional regulation of BnaALMTs in the roots and leaves at both a sufficient and a deficient P supply. Thirty-nine BnaALMT genes were identified and were clustered into five branches in the phylogenetic tree based on protein sequences. Collinearity analysis revealed that most of the BnaALMT genes shared syntenic relationships among BnaALMT members in B. napus, which suggested that whole-genome duplication (polyploidy) played a major driving force for BnaALMTs evolution in addition to segmental duplication. RNA-seq analyses showed that most BnaALMT genes were preferentially expressed in root and leaf tissues. Among them, the expression of BnaC08g13520D, BnaC08g15170D, BnaC08g15180D, BnaC08g13490D, BnaC08g13500D, BnaA08g26960D, BnaC05g14120D, BnaA06g12560D, BnaC05g20630D, BnaA07g02630D, BnaA04g15700D were significantly up-regulated in B. napus roots and leaf at a P deficient supply. The current study analyzes the evolution and the expression of the ALMT family in B. napus, which will help in further research on their role in the enhancement of soil P availability by secretion of organic acids.


Assuntos
Alumínio/metabolismo , Brassica napus/genética , Evolução Molecular , Malatos/metabolismo , Transportadores de Ânions Orgânicos/genética , Fosfatos/metabolismo , Proteínas de Arabidopsis/genética , Cromossomos de Plantas , Genoma de Planta , Família Multigênica , Transportadores de Ânions Orgânicos/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...