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1.
Food Chem ; 332: 127382, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32619943

RESUMO

Sea buckthorn (Hippophaë rhamnoides L.) berries have high biological value as a rich source of phenolic compounds, fatty acids and vitamins A, C, E. Due to the high organic acid content and sour taste, the fruits are rarely used in juice production. Therefore, the study aimed to determine the metabolic activity of Lactobacillus plantarum, Lactobacillus plantarum subsp. argentoratensis and Oenococcus oeni strains along with the dynamics of changes in organic acids, sugars, phenolic compounds, and antioxidant activity during 72-h fermentation of 100% sea buckthorn and mixed with apple (1:1) juices. The strongest malolactic conversion was in mixed juices (to 75.0%). The most efficient strains were L. plantarum DSM 10492, 20174 and 6872. L. plantarum strains caused an increase in flavonols and antioxidant activity of sea buckthorn-apple juices. The results can be used to select conditions and strains in industrial-scale fermentation, to produce novel sea buckthorn products and increase their consumption.


Assuntos
Antioxidantes/química , Sucos de Frutas e Vegetais/análise , Ácido Láctico/metabolismo , Malatos/metabolismo , Fenóis/metabolismo , Açúcares/metabolismo , Fermentação , Flavonóis/química , Flavonóis/metabolismo , Frutas/química , Frutas/metabolismo , Hippophae/química , Hippophae/metabolismo , Concentração de Íons de Hidrogênio , Lactobacillus/crescimento & desenvolvimento , Lactobacillus/metabolismo , Malus/química , Malus/metabolismo , Oenococcus/crescimento & desenvolvimento , Oenococcus/metabolismo , Fenóis/química
2.
PLoS One ; 15(7): e0236530, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32706831

RESUMO

Apple trees grafted on different rootstock types, including vigorous rootstock (VR), dwarfing interstock (DIR), and dwarfing self-rootstock (DSR), are widely planted in production, but the molecular determinants of tree branch architecture growth regulation induced by rootstocks are still not well known. In this study, the branch growth phenotypes of three combinations of 'Fuji' apple trees grafted on different rootstocks (VR: Malus baccata; DIR: Malus baccata/T337; DSR: T337) were investigated. The VR trees presented the biggest branch architecture. The results showed that the sugar content, sugar metabolism-related enzyme activities, and hormone content all presented obvious differences in the tender leaves and buds of apple trees grafted on these rootstocks. Transcriptomic profiles of the tender leaves adjacent to the top buds allowed us to identify genes that were potentially involved in signaling pathways that mediate the regulatory mechanisms underlying growth differences. In total, 3610 differentially expressed genes (DEGs) were identified through pairwise comparisons. The screened data suggested that sugar metabolism-related genes and complex hormone regulatory networks involved the auxin (IAA), cytokinin (CK), abscisic acid (ABA) and gibberellic acid (GA) pathways, as well as several transcription factors, participated in the complicated growth induction process. Overall, this study provides a framework for analysis of the molecular mechanisms underlying differential tree branch growth of apple trees grafted on different rootstocks.


Assuntos
Regulação da Expressão Gênica de Plantas , Malus/genética , Transdução de Sinais/genética , Açúcares/metabolismo , Ácido Abscísico/análise , Ácido Abscísico/metabolismo , Cromatografia Líquida de Alta Pressão , Citocininas/análise , Citocininas/metabolismo , Flores/genética , Flores/metabolismo , Giberelinas/análise , Giberelinas/metabolismo , Ácidos Indolacéticos/análise , Ácidos Indolacéticos/metabolismo , Malus/crescimento & desenvolvimento , Fenótipo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Caules de Planta/genética , Caules de Planta/fisiologia , RNA de Plantas/genética , RNA de Plantas/metabolismo , Açúcares/análise , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , alfa-Glucosidases/genética , alfa-Glucosidases/metabolismo
3.
Sheng Wu Gong Cheng Xue Bao ; 36(5): 861-867, 2020 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-32567269

RESUMO

Lignocellulose is a major biomass resource for the production of biofuel ethanol. Due to its abundance, environmental friendliness and renewability, the utilization of lignocellulose is promising to solve energy shortage. Surfactant can effectively promote the enzymatic hydrolysis of lignocellulose. By discussing the influence and mechanism of different surfactants on the enzymatic hydrolysis, we provide references for finding appropriate surfactants in enzymatic hydrolysis process.


Assuntos
Lignina , Açúcares , Biocombustíveis , Biomassa , Hidrólise/efeitos dos fármacos , Lignina/metabolismo , Açúcares/metabolismo , Tensoativos/farmacologia
4.
PLoS One ; 15(6): e0226469, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32525873

RESUMO

Colour is an important signal that flowering plants use to attract insect pollinators like bees. Previous research in Germany has shown that nectar volume is higher for flower colours that are innately preferred by European bees, suggesting an important link between colour signals, bee preferences and floral rewards. In Australia, flower colour signals have evolved in parallel to the Northern hemisphere to enable easy discrimination and detection by the phylogenetically ancient trichromatic visual system of bees, and native Australian bees also possess similar innate colour preferences to European bees. We measured 59 spectral signatures from flowers present at two preserved native habitats in South Eastern Australia and tested whether there were any significant differences in the frequency of flowers presenting higher nectar rewards depending upon the colour category of the flower signals, as perceived by bees. We also tested if there was a significant correlation between chromatic contrast and the frequency of flowers presenting higher nectar rewards. For the entire sample, and for subsets excluding species in the Asteraceae and Orchidaceae, we found no significant difference among colour categories in the frequency of high nectar reward. This suggests that whilst such relationships between flower colour signals and nectar volume rewards have been observed at a field site in Germany, the effect is likely to be specific at a community level rather than a broad general principle that has resulted in the common signalling of bee flower colours around the world.


Assuntos
Abelhas/fisiologia , Flores/metabolismo , Pigmentação , Néctar de Plantas/metabolismo , Polinização , Animais , Comportamento Animal , Açúcares/metabolismo
5.
PLoS One ; 15(5): e0232875, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32407357

RESUMO

Water uptake into seeds is a fundamental prerequisite of germination and commonly influenced by commercial seed enhancement technologies. The effect of fruit orientation and contrasting pelleting materials on germination and biological performance of sugar beet was assessed. The results indicated there was orientation dependent fruit shrinkage of 37% for the operculum side supplied by moisture compared to 4% for the basal pore side. The expansion rate of 5% compared to the original size, which was also observed for non-shrinking seeds, indicated this was a temporary effect. This behaviour has importance for the application pelleting materials to seeds. Pellets composed of materials exhibiting low levels of swelling act as a water distribution layer which increased germination rates. Careful selection of pelleting material is crucial as it has direct implications on germination speed and subsequent establishment rates.


Assuntos
Agricultura/métodos , Beta vulgaris/fisiologia , Frutas/química , Germinação , Sementes/fisiologia , Açúcares/metabolismo , Água/metabolismo , Beta vulgaris/química , Beta vulgaris/crescimento & desenvolvimento , Frutas/fisiologia , Orientação Espacial , Sementes/química , Sementes/crescimento & desenvolvimento
6.
Nat Commun ; 11(1): 2456, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415123

RESUMO

Anthocyanin pigments furnish a powerful visual output of the stress and metabolic status of Arabidopsis thaliana plants. Essential for pigment accumulation is TRANSPARENT TESTA19 (TT19), a glutathione S-transferase proposed to bind and stabilize anthocyanins, participating in their vacuolar sequestration, a function conserved across the flowering plants. Here, we report the identification of genetic suppressors that result in anthocyanin accumulation in the absence of TT19. We show that mutations in RDR6, SGS3, or DCL4 suppress the anthocyanin defect of tt19 by pushing carbon towards flavonoid biosynthesis. This effect is not unique to tt19 and extends to at least one other anthocyanin pathway gene mutant. This synergy between mutations in components of the RDR6-SGS3-DCL4 siRNA system and the flavonoid pathway reveals genetic/epigenetic mechanisms regulating metabolic fluxes.


Assuntos
Antocianinas/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Carbono/metabolismo , RNA Replicase/metabolismo , RNA Interferente Pequeno/metabolismo , Ribonuclease III/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Sequência de Bases , Regulação da Expressão Gênica de Plantas , Genes Supressores , Genótipo , Glutationa Transferase/genética , Mutação/genética , Fenótipo , Pigmentação/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Plântula/crescimento & desenvolvimento , Açúcares/metabolismo
7.
PLoS One ; 15(4): e0231101, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32302339

RESUMO

Mast cells and basophils are central players in allergic reactions triggered by immunoglobulin E (IgE). They have intracellular granules containing allergic mediators (e.g., histamine, serotonin, inflammatory cytokines, proteases and ß-hexosaminidase), and stimulation by IgE-allergen complex leads to the release of such allergic mediators from the granules, that is, degranulation. Mast cells are residents of mucosal surfaces, including those of nasal and oral cavities, and play an important role in the innate defense system. Members of the mitis group streptococci such as Streptococcus oralis, are primary colonizers of the human oral cavity. They produce hydrogen peroxide (H2O2) as a by-product of sugar metabolism. In this study, we investigated the effects of streptococcal infection on RBL-2H3 mast cell/basophil cell line. Infection by oral streptococci did not induce degranulation of the cells. Stimulation of the RBL-2H3 cells with anti-dinitrophenol (DNP) IgE and DNP-conjugated human serum albumin triggers degranulation with the release of ß-hexosaminidase. We found that S. oralis and other mitis group streptococci inhibited the IgE-triggered degranulation of RBL-2H3 cells. Since mitis group streptococci produce H2O2, we examined the effect of S. oralis mutant strain deficient in producing H2O2, and found that they lost the ability to suppress the degranulation. Moreover, H2O2 alone inhibited the IgE-induced degranulation. Subsequent analysis suggested that the inhibition of degranulation was related to the cytotoxicity of streptococcal H2O2. Activated RBL-2H3 cells produce interleukin-4 (IL-4); however, IL-4 production was not induced by streptococcal H2O2. Furthermore, an in vivo study using the murine pollen-induced allergic rhinitis model suggested that the streptococcal H2O2 reduces nasal allergic reaction. These findings reveal that H2O2 produced by oral mitis group streptococci inhibits IgE-stimulated degranulation by inducing cell death. Consequently, streptococcal H2O2 can be considered to modulate the allergic reaction in mucosal surfaces.


Assuntos
Alérgenos/metabolismo , Hipersensibilidade/imunologia , Imunoglobulina E/imunologia , Infecções Estreptocócicas/tratamento farmacológico , Alérgenos/imunologia , Animais , Basófilos/imunologia , Basófilos/microbiologia , Basófilos/patologia , Degranulação Celular/imunologia , Sobrevivência Celular/imunologia , Dinitrofenóis/farmacologia , Humanos , Peróxido de Hidrogênio/metabolismo , Hipersensibilidade/tratamento farmacológico , Hipersensibilidade/patologia , Imunoglobulina E/metabolismo , Interleucina-4/genética , Interleucina-4/metabolismo , Mastócitos/imunologia , Mastócitos/microbiologia , Mastócitos/patologia , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Albumina Sérica Humana/imunologia , Albumina Sérica Humana/metabolismo , Infecções Estreptocócicas/imunologia , Streptococcus oralis/imunologia , Streptococcus oralis/patogenicidade , Açúcares/metabolismo
8.
Chemosphere ; 249: 126463, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32213388

RESUMO

The brown planthopper (BPH), Nilaparvata lugens, is a resurgent pest with an unexpected response to jinggangmycin (JGM), a broadly applied antibiotic used to control rice sheath blight disease. JGM stimulates BPH fecundity, but the underlining molecular mechanisms remain unclear. Here we report that JGM sprays led to increased glucose concentrations, photosynthesis and gene expression, specifically Rubsico, sucrose phosphate synthase, invertase 2 (INV2) and INV3 in rice plants. JGM sprays led to high-glucose rice plants. Feeding BPH on these plants led to increased insulin-like signaling and vitellogenin synthesis. Treating BPH with metformin, a gluconeogenesis inhibitor, reversed the influence of feeding on high-glucose rice, which was rescued by glucose injections. Silencing insulin-like peptide 2 using per os dsRNA led to reduction in juvenile hormone (JH) III titers and other fecundity parameters, which were reversed by topical applications of the JH analog, methoprene. We infer that JGM acts via two broad mechanisms, one through increasing rice plant sugar concentrations and a second by upregulating BPH insulin-like signaling.


Assuntos
Antibacterianos/farmacologia , Hemípteros/fisiologia , Inositol/análogos & derivados , Oryza/metabolismo , Animais , Fertilidade/efeitos dos fármacos , Inositol/farmacologia , Insulina/metabolismo , RNA de Cadeia Dupla , Açúcares/metabolismo
9.
Gene ; 742: 144584, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32173541

RESUMO

Sugars are considered as an essential signaling molecule for fruit growth and development, which plays a key role in fruit quality. Up to now, the mechanism controlling sugar metabolism and transport in apricot is unclear. Therefore, in the present study, we measured sugar contents at six different stages of fruit development and ripening, and significant variations were observed throughout these stages. The concentration of glucose and fructose first decreased then increased, sucrose concentration first increased then decreased, while the concentration of sorbitol gradually decreased from growth to maturity. Furthermore, thirty sugar transporter genes related to sucrose synthesis and transport were identified and categorized into different subfamilies based on the phylogenetic analysis. The result of cis-regulatory components showed that under different plant hormones, biotic and abiotic stresses, few elements could be regulated. The correlation analysis showed a higher relationship between ParSuSy5, ParSuSy6, ParSuSy7, and ParFK1 genes and sugar contents, indicating that these genes might have a key role in sugar accumulation and fruit quality. In general, these findings will provide a deep understanding of genomic information and expression profiles of sugar transporter genes, which will contribute toward improvement in fruit quality of apricot.


Assuntos
Frutas/crescimento & desenvolvimento , Proteínas de Membrana Transportadoras/genética , Proteínas de Plantas/genética , Prunus armeniaca/fisiologia , Açúcares/metabolismo , Metabolismo dos Carboidratos/genética , Frutas/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Horticultura/organização & administração , Proteínas de Membrana Transportadoras/metabolismo , Filogenia , Melhoramento Vegetal , Proteínas de Plantas/metabolismo , Melhoria de Qualidade
10.
Gene ; 743: 144582, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32173543

RESUMO

As the main energy source for generating ATP during plant growth and development, sugars are synthesized in leaves, while sugar allocation depends on both intracellular transport between different organelles and source-to-sink transport. However, sugar transport related research is limited in pear. Here, a sugar transporter PbSWEET4 was identified that control sugar content and senescence in leaf. Phylogenetic analysis and multiple sequence alignment results indicated that PbSWEET4 was homologous to AtSWEET15, which contained two conserved domains and could promote senescence. The qRT-PCR and transcriptome database result showed that the expression of PbSWEET4 was positively correlated with leaf development, especially highly expressed in older leaves. Furthermore, the evaluation of promoter-GUS activity also indicated that PbSWEET4 exhibited the highest expression level in older leaves. The subcellular localization revealed that the PbSWEET4 localized in the plasma membrane. Finally, overexpression of the PbSWEET4 in strawberry plants could reduce leaf sugar content and chlorophyll content, while accelerate leaf senescence, which might be due to enhanced export of sugars from leaves. These results enrich the knowledge about the function of sugar exporter in regulating the fruit species development, and provide a novel genetic resource for future improvement in carbohydrate partitioning for pear and other fruit trees.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Membrana Transportadoras/genética , Proteínas de Plantas/genética , Pyrus/fisiologia , Membrana Celular/metabolismo , Senescência Celular/genética , Clorofila/análise , Fragaria/genética , Proteínas de Membrana Transportadoras/metabolismo , Folhas de Planta/química , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Pyrus/química , Açúcares/análise , Açúcares/metabolismo
11.
PLoS One ; 15(2): e0221737, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32017762

RESUMO

Bioethanol production from lignocellulosic biomass has received increasing attention over the past decade. Many attempts have been made to reduce the cost of bioethanol production by combining the separate steps of the process into a single-step process known as consolidated bioprocessing. This requires identification of organisms that can efficiently decompose lignocellulose to simple sugars and ferment the pentose and hexose sugars liberated to ethanol. There have been many attempts in engineering laboratory strains by adding new genes or modifying genes to expand the capacity of an industrial microorganism. There has been less attention in improving bioethanol-related processes utilizing natural variation existing in the natural ecotypes. In this study, we sought to identify genomic loci contributing to variation in saccharification of cellulose and fermentation of glucose in the fermenting cellulolytic fungus Neurospora crassa through quantitative trait loci (QTL) analysis. We identified one major QTL contributing to fermentation of glucose and multiple putative QTL's underlying saccharification. Understanding the natural variation of the major QTL gene would provide new insights in developing industrial microbes for bioethanol production.


Assuntos
Variação Biológica da População/genética , Etanol/metabolismo , Neurospora crassa/genética , Locos de Características Quantitativas , Fermentação , Microbiologia Industrial , Açúcares/metabolismo
12.
Int J Food Microbiol ; 320: 108500, 2020 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-32007764

RESUMO

Stress has been defined as any environmental factor that impairs the growth of a living organism. High concentrations of ethanol, sugars and SO2 as well as temperature variations occurring during winemaking processes are some recognized stress factors that yeasts must overcome in order to avoid stuck or sluggish fermentations. At least two of these factors -sugar and ethanol concentrations- are strongly influenced by the global warming, which become them a worry for the future years in the winemaking industry. One of the most interesting strategies to face this complex situation is the generation of hybrids possessing, in a single yeast strain, a broader range of stress factors tolerance than their parents. In the present study, we evaluated four artificial hybrids generated with S. cerevisiae, S. uvarum and S. eubayanus using a non-GMO-generating method, in their tolerance to a set of winemaking stress factors. Their capacity to overcome specific artificial winemaking situations associated with global warming was also analyzed. All four hybrids were able to grow in a wider temperature range (8-37 °C) than their parents. Hybrids showed intermediate tolerance to higher ethanol, sugar and sulphite concentrations than their parents. Additionally, the hybrids showed an excellent fermentative behaviour in musts containing high fructose concentrations at low temperature as well as under a condition mimicking a stuck fermentation.


Assuntos
Adaptação Fisiológica/genética , Saccharomyces/genética , Vinho/microbiologia , Mudança Climática , Etanol/metabolismo , Fermentação , Microbiologia de Alimentos , Saccharomyces/crescimento & desenvolvimento , Saccharomyces/metabolismo , Açúcares/metabolismo , Sulfitos/metabolismo , Temperatura
13.
J Nutr ; 150(4): 704-711, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32060554

RESUMO

BACKGROUND: The association between high selenium (Se) intake and metabolic disorders such as type 2 diabetes has raised great concern, but the underlying mechanism remains unclear. OBJECTIVE: Through targeted metabolomics analysis, we examined the liver sugar and acylcarnitine metabolism responses to supranutritional selenomethionine (SeMet) supplementation in pigs. METHODS: Thirty-six castrated male pigs (Duroc-Landrace-Yorkshire, 62.0 ± 3.3 kg) were fed SeMet adequate (Se-A, 0.25 mg Se/kg) or SeMet supranutritional (Se-S, 2.5 mg Se/kg) diets for 60 d. The Se concentration, biochemical, gene expression, enzyme activity, and energy-targeted metabolite profiles were analyzed. RESULTS: The Se-S group had greater fasting serum concentrations of glucose (1.9-fold), insulin (1.4-fold), and free fatty acids (FFAs,1.3-fold) relative to the Se-A group (P < 0.05). The liver total Se concentration was 4.2-fold that of the Se-A group in the Se-S group (P < 0.05), but expression of most selenoprotein genes and selenoenzyme activity did not differ between the 2 groups. Seven of 27 targeted sugar metabolites and 4 of 21 acylcarnitine metabolites significantly changed in response to high SeMet (P < 0.05). High SeMet supplementation significantly upregulated phosphoenolpyruvate carboxy kinase (PEPCK) activity by 64.4% and decreased hexokinase and succinate dehydrogenase (SDH) activity by 46.5-56.7% (P < 0.05). The relative contents of glucose, dihydroxyacetone phosphate, α-ketoglutarate, fumarate, malate, erythrose-4-phosphate, and sedoheptulose-7-phosphate in the Se-S group were 21.1-360% greater than those in the Se-A group (P < 0.05). The expression of fatty acid synthase (FASN) and the relative contents of carnitine, hexanoyl-carnitine, decanoyl-carnitine, and tetradecanoyl-carnitine in the Se-S group were 35-97% higher than those in the Se-A group (P < 0.05). CONCLUSIONS: Dietary high SeMet-induced hyperglycemia and hyperinsulinemia were associated with suppression of sugar metabolism and elevation of lipid synthesis in pig livers. Our research provides novel insights into high SeMet intake-induced type 2 diabetes.


Assuntos
Carnitina/análogos & derivados , Dieta , Fígado/metabolismo , Selenometionina/administração & dosagem , Açúcares/metabolismo , Animais , Carnitina/metabolismo , Diabetes Mellitus Tipo 2/induzido quimicamente , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Homeostase/efeitos dos fármacos , Hiperglicemia/induzido quimicamente , Hiperinsulinismo/induzido quimicamente , Lipídeos/biossíntese , Fígado/química , Fígado/enzimologia , Masculino , Metabolômica/métodos , Modelos Animais , Oxirredução , RNA Mensageiro/análise , Selênio/administração & dosagem , Selênio/efeitos adversos , Selênio/análise , Selenometionina/efeitos adversos , Selenoproteínas/genética , Sus scrofa
14.
Int J Food Microbiol ; 321: 108546, 2020 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-32087410

RESUMO

The demand for sugar reduction in products across the food and beverage industries has evoked the development of novel processes including the application of fermentation with lactic acid bacteria. Heterofermentative lactic acid bacteria (LAB) are diverse in their ability to utilise fermentable sugars and can also convert fructose into the sweet tasting polyol, mannitol. The sourdough microbiota has long been recognised as an ecological niche for a range of homofermentative and heterofermentative lactic acid bacteria. A leading determinant in the biodiversity of sourdough microbial populations is the type of flour used. Ten non-wheat flours were used and back-slopped for 7 days resulting in the isolation of 52 mannitol producing isolates which spanned six heterofermentative species of the genera Lactobacillus, Leuconostoc and Weissella. Assessment of mannitol productivity in fructose concentrations up to 100 g/L found Leuconostoc citreum TR116, to have the best mannitol producing characteristics, consuming 95% of available fructose and yielding 0.68 g of mannitol per gram of fructose consumed which equates to the maximal theoretical yield. Investigation of the effects of initial pH on mannitol production and other fermentation parameters in the isolates found pH 7 to be best for isolates Lactobacillus brevis TR052, Leuconostoc fallax TR111, Leuconostoc citreum TR116, Leuconostoc mesenteroides TR154 and Weissella paramesenteroides TR212, while pH 6 was optimal for Leuconostoc pseudomesenteroides TR080. The fermentation of apple juice with each isolate resulted in sugar reduction ranging from 30.3-74.0 g/L (34-72%). When apple juice fermentation with Leuconostoc citreum TR116 was scaled up to 1 L bioreactor a reduction in sugar of 98.6 g/L (83%) was achieved along with the production of 61.6 g/L mannitol. This demonstrates a fermentative process for sugar reduction in fruit juice with concomitant production of the sweet metabolite mannitol to create a fermentate that is suitable for further development as a low sugar fruit juice alternative.


Assuntos
Lactobacillales/isolamento & purificação , Lactobacillales/metabolismo , Manitol/metabolismo , Açúcares/metabolismo , Biodiversidade , Reatores Biológicos/microbiologia , Pão/microbiologia , Fermentação , Microbiologia de Alimentos , Frutose/metabolismo , Concentração de Íons de Hidrogênio , Lactobacillales/classificação
15.
OMICS ; 24(2): 62-80, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32027574

RESUMO

Precision/personalized medicine is a hot topic in health care. Often presented with the motto "the right drug, for the right patient, at the right dose, and the right time," precision medicine is a theory for rational therapeutics as well as practice to individualize health interventions (e.g., drugs, food, vaccines, medical devices, and exercise programs) using biomarkers. Yet, an alien visitor to planet Earth reading the contemporary textbooks on diagnostics might think precision medicine requires only two biomolecules omnipresent in the literature: nucleic acids (e.g., DNA) and proteins, known as the first and second alphabet of biology, respectively. However, the precision/personalized medicine community has tended to underappreciate the third alphabet of life, the "sugar code" (i.e., the information stored in glycans, glycoproteins, and glycolipids). This article brings together experts in precision/personalized medicine science, pharmacoglycomics, emerging technology governance, cultural studies, contemporary art, and responsible innovation to critically comment on the sociomateriality of the three alphabets of life together. First, the current transformation of targeted therapies with personalized glycomedicine and glycan biomarkers is examined. Next, we discuss the reasons as to why unraveling of the sugar code might have lagged behind the DNA and protein codes. While social scientists have historically noted the importance of constructivism (e.g., how people interpret technology and build their values, hopes, and expectations into emerging technologies), life scientists relied on the material properties of technologies in explaining why some innovations emerge rapidly and are more popular than others. The concept of sociomateriality integrates these two explanations by highlighting the inherent entanglement of the social and the material contributions to knowledge and what is presented to us as reality from everyday laboratory life. Hence, we present a hypothesis based on a sociomaterial conceptual lens: because materiality and synthesis of glycans are not directly driven by a template, and thus more complex and open ended than sequencing of a finite length genome, social construction of expectations from unraveling of the sugar code versus the DNA code might have evolved differently, as being future-uncertain versus future-proof, respectively, thus potentially explaining the "sugar lag" in precision/personalized medicine diagnostics over the past decades. We conclude by introducing systems scientists, physicians, and biotechnology industry to the concept, practice, and value of responsible innovation, while glycomedicine and other emerging biomarker technologies (e.g., metagenomics and pharmacomicrobiomics) transition to applications in health care, ecology, pharmaceutical/diagnostic industries, agriculture, food, and bioengineering, among others.


Assuntos
Biomarcadores , Medicina de Precisão , Açúcares/metabolismo , Gerenciamento Clínico , Suscetibilidade a Doenças , História do Século XX , História do Século XXI , Humanos , Invenções , Polissacarídeos/biossíntese , Medicina de Precisão/história , Medicina de Precisão/métodos
16.
Cell Mol Life Sci ; 77(18): 3469-3502, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32006052

RESUMO

Throughout the animal kingdom sucrose is one of the most palatable and preferred tastants. From an evolutionary perspective, this is not surprising as it is a primary source of energy. However, its overconsumption can result in obesity and an associated cornucopia of maladies, including type 2 diabetes and cardiovascular disease. Here we describe three physiological levels of processing sucrose that are involved in the decision to ingest it: the tongue, gut, and brain. The first section describes the peripheral cellular and molecular mechanisms of sweet taste identification that project to higher brain centers. We argue that stimulation of the tongue with sucrose triggers the formation of three distinct pathways that convey sensory attributes about its quality, palatability, and intensity that results in a perception of sweet taste. We also discuss the coding of sucrose throughout the gustatory pathway. The second section reviews how sucrose, and other palatable foods, interact with the gut-brain axis either through the hepatoportal system and/or vagal pathways in a manner that encodes both the rewarding and of nutritional value of foods. The third section reviews the homeostatic, hedonic, and aversive brain circuits involved in the control of food intake. Finally, we discuss evidence that overconsumption of sugars (or high fat diets) blunts taste perception, the post-ingestive nutritional reward value, and the circuits that control feeding in a manner that can lead to the development of obesity.


Assuntos
Obesidade/patologia , Açúcares/metabolismo , Paladar/fisiologia , Animais , Encéfalo/metabolismo , Humanos , Leptina/metabolismo , Neurônios/metabolismo , Valor Nutritivo , Obesidade/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo
17.
BMC Plant Biol ; 20(1): 10, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31910796

RESUMO

BACKGROUND: Cytoplasmic male sterility (CMS) plays a crucial role in the utilization of heterosis and various types of CMS often have different abortion mechanisms. Therefore, it is important to understand the molecular mechanisms related to anther abortion in wheat, which remain unclear at present. RESULTS: In this study, five isonuclear alloplasmic male sterile lines (IAMSLs) and their maintainer were investigated. Cytological analysis indicated that the abortion type was identical in IAMSLs, typical and stainable abortion, and the key abortive period was in the binucleate stage. Most of the 1,281 core shared differentially expressed genes identified by transcriptome sequencing compared with the maintainer in the vital abortive stage were involved in the metabolism of sugars, oxidative phosphorylation, phenylpropane biosynthesis, and phosphatidylinositol signaling, and they were downregulated in the IAMSLs. Key candidate genes encoding chalcone--flavonone isomerase, pectinesterase, and UDP-glucose pyrophosphorylase were screened and identified. Moreover, further verification elucidated that due to the impact of downregulated genes in these pathways, the male sterile anthers were deficient in sugar and energy, with excessive accumulations of ROS, blocked sporopollenin synthesis, and abnormal tapetum degradation. CONCLUSIONS: Through comparative transcriptome analysis, an intriguing core transcriptome-mediated male-sterility network was proposed and constructed for wheat and inferred that the downregulation of genes in important pathways may ultimately stunt the formation of the pollen outer wall in IAMSLs. These findings provide insights for predicting the functions of the candidate genes, and the comprehensive analysis of our results was helpful for studying the abortive interaction mechanism in CMS wheat.


Assuntos
Regulação da Expressão Gênica de Plantas/genética , Redes Reguladoras de Genes , Infertilidade das Plantas/genética , Transcriptoma/genética , Triticum , Biopolímeros/metabolismo , Carotenoides/metabolismo , Flores/citologia , Flores/ultraestrutura , Perfilação da Expressão Gênica/métodos , Ontologia Genética/estatística & dados numéricos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Infertilidade das Plantas/fisiologia , Proteínas de Plantas/genética , Pólen/citologia , Pólen/ultraestrutura , Espécies Reativas de Oxigênio/metabolismo , Açúcares/metabolismo , Triticum/citologia , Triticum/genética , Triticum/metabolismo
18.
Chem Commun (Camb) ; 56(15): 2344-2347, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31993612

RESUMO

In our report, we found a distinct difference in azido sugar metabolic rate between neural stem cells and fibroblasts, which can be used for selective removal of fibroblasts from neural stem cell mixtures. Chemically induced neural stem cells (ciNSCs) serve as a highly valuable source of NSCs. Incompletely induced fibroblasts could interfere with ciNSC differentiation and become tumorigenic. Herein, we applied our method for the decontamination of ciNSCs and it exhibited excellent selectivity for ciNSCs. The results demonstrate that the ciNSC population can be efficiently purified to 98.1%. As far as we know, this is the highest purity obtained so far. We envision that, in the future, our method could be used as a safe, effective, and chemically-defined tool for decontaminating ciNSCs in both fundamental research and clinical stem cell therapy.


Assuntos
Azidas/metabolismo , Fibroblastos/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Neurais/metabolismo , Açúcares/metabolismo , Células 3T3 , Animais , Azidas/química , Proliferação de Células , Fibroblastos/química , Células-Tronco Pluripotentes Induzidas/química , Camundongos , Células-Tronco Neurais/química , Açúcares/química
19.
Nature ; 578(7794): 321-325, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31996846

RESUMO

Elucidating the mechanism of sugar import requires a molecular understanding of how transporters couple sugar binding and gating events. Whereas mammalian glucose transporters (GLUTs) are specialists1, the hexose transporter from the malaria parasite Plasmodium falciparum PfHT12,3 has acquired the ability to transport both glucose and fructose sugars as efficiently as the dedicated glucose (GLUT3) and fructose (GLUT5) transporters. Here, to establish the molecular basis of sugar promiscuity in malaria parasites, we determined the crystal structure of PfHT1 in complex with D-glucose at a resolution of 3.6 Å. We found that the sugar-binding site in PfHT1 is very similar to those of the distantly related GLUT3 and GLUT5 structures4,5. Nevertheless, engineered PfHT1 mutations made to match GLUT sugar-binding sites did not shift sugar preferences. The extracellular substrate-gating helix TM7b in PfHT1 was positioned in a fully occluded conformation, providing a unique glimpse into how sugar binding and gating are coupled. We determined that polar contacts between TM7b and TM1 (located about 15 Å from D-glucose) are just as critical for transport as the residues that directly coordinate D-glucose, which demonstrates a strong allosteric coupling between sugar binding and gating. We conclude that PfHT1 has achieved substrate promiscuity not by modifying its sugar-binding site, but instead by evolving substrate-gating dynamics.


Assuntos
Malária/parasitologia , Proteínas de Transporte de Monossacarídeos/química , Proteínas de Transporte de Monossacarídeos/metabolismo , Plasmodium falciparum/química , Plasmodium falciparum/metabolismo , Açúcares/metabolismo , Regulação Alostérica , Motivos de Aminoácidos , Sequência de Aminoácidos , Sítios de Ligação , Transporte Biológico , Cristalografia por Raios X , Glucose/química , Glucose/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/química , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Humanos , Modelos Moleculares , Conformação Proteica , Especificidade por Substrato
20.
Sci China Life Sci ; 63(2): 228-238, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31919631

RESUMO

The palea and lemma are floral organ structures unique to grasses; these structures form the hull and directly affect grain size and quality. However, the molecular mechanisms controlling the development of the hull are not well understood. In this study, we characterized the rice (Oryza sativa) abnormal flower and grain1 (afg1) mutant, a new allele of OsMADS6. Similar to previously characterized osmads6 alleles, in the afg1 floret, the palea lost its marginal region and acquired the lemma identity. However, in contrast to other osmads6 alleles, the afg1 mutant showed altered grain size and grain quality, with decreased total starch and amylose contents, and increased protein and soluble sugar contents. The analysis of transcriptional activity suggested that AFG1 is a transcriptional activator and may affect grain size by regulating the expression levels of several genes related to cell expansion and proliferation in the afg1 mutant. These results revealed that AFG1 plays an important role in determining palea identity and affecting grain yield and quality in rice.


Assuntos
Grão Comestível/genética , Flores/genética , Proteínas de Domínio MADS/genética , Oryza/genética , Proteínas de Plantas/genética , Alelos , Sequência de Aminoácidos , Amilose/genética , Mapeamento Cromossômico , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Proteínas de Domínio MADS/metabolismo , Mutação/genética , Oryza/crescimento & desenvolvimento , Fenótipo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Amido/genética , Açúcares/metabolismo , Transcrição Genética
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