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1.
J Colloid Interface Sci ; 606(Pt 2): 1284-1298, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492466

RESUMO

2D/2D heterojunction photocatalysts with excellent photocatalytic activity highlight considerable potential in water disinfection. Here, an oxidized Sb/g-C3N4 2D/2D nanosheets heterojunction (Sb-SbOx/CNS) was constructed based on a facile one-step liquid-phase exfoliation method using concentrated sulfuric acid. By doing so, bulk Sb and g-C3N4 were exfoliated simultaneously and then, intercalated each other. Compared with CNS and Sb-SbOx, the obtained Sb-SbOx/CNS demonstrated better photocatalytic disinfection activity towards Escherichia coli K-12 (E. coli K-12) under visible light irradiation. The 5% oxidized Sb/g-C3N4 2D/2D nanosheets heterojunction (5.0% Sb-SbOx/CNS) exhibited the best photocatalytic performance and admirable cycling stability, which was ascribed to the unique structure where the interfacial charge separation was strengthened by the strong coupling effect between Sb-SbOx and CNS. Meanwhile, the fundamental mechanism of photocatalytic disinfection was also proposed. The photogenerated ROS (reactive oxygen species) violently attacked the E. coli K-12 membrane, creating massive and irreparable holes on the cell membrane. The leakage of cations (K+, Na+, Ca2+ and Mg2+), adenosine triphosphate, total soluble sugar and protein accelerated the destruction of E. coli K-12. Trapping experiments suggested that the photocatalytic disinfection process against E. coli K-12 was dominated by h+ generated on 5.0% Sb-SbOx/CNS. This work offers a new promising way to modify the 2D/2D heterojunction featuring efficient photocatalytic disinfection performance.


Assuntos
Desinfecção , Escherichia coli K12 , Catálise , Escherichia coli , Luz
2.
Exp Eye Res ; 213: 108820, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34728181

RESUMO

Human corneal endothelial cells (CECs) have limited ability to regenerate in vivo. Oxidative stress has been proposed as one potential reason. Understanding the mechanism of oxidative stress-induced CEC dysfunction might provide novel targets for improving CEC regenerative capacity, and help develop non-surgical therapeutic strategies for CEC dysfunction. Long non-coding RNAs (lncRNAs) are non-coding transcripts with multiple biological functions. The roles of lncRNAs in ocular cells under oxidative stress have been widely studied, such as lens epithelial cells, trabecular meshwork cells, and retinal ganglion cells. In the current study, we established oxidative stress-induced CEC dysfunction model in vitro. By RNA sequencing technology, we identified 824 differentially expressed lncRNAs in CEC dysfunction group, including 667 upregulated lncRNAs and 157 downregulated lncRNAs. We finally demonstrated that CEC functions under oxidative stress, including cellular proliferation, apoptosis, and anti-oxidative stress ability, could be regulated by different lncRNAs, including lncRNA-Z93241.1, lncRNA-XLOC_000818, and lncRNA-AC007952.4. Targeting these lncRNAs might be useful to further elucidate the pathology of CEC dysfunction and develop novel therapeutic strategy.

3.
Macromol Biosci ; : e2100349, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34735739

RESUMO

Since the conceptualization of nanomedicine, numerous nanostructure-mediated drug formulations have progressed into clinical trials for treating cancer. However, recent clinical trial results indicate such kind of drug formulations has a limited improvement on the antitumor efficacy. This is due to the biological barriers associated with those formulations, for example, circulation stability, extravasation efficiency in tumor, tumor penetration ability, and developed multi-drug resistance. When employing for nanomedicine formulations, pristine organic-based and inorganic-based nanostructures have their own limitations. Accordingly, organic/inorganic (O/I) hybrids have been developed to integrate the merits of both, and to minimize their intrinsic drawbacks. In this context, the recent development in O/I hybrids resulting from a self-assembly strategy will be introduced. Through such a strategy, organic and inorganic building blocks can be self-assembled via either chemical covalent bonds or physical interactions. Based on the self-assemble procedure, the hybridization of four organic building blocks including liposomes, micelles, dendrimers, and polymeric nanocapsules with five functional inorganic nanoparticles comprising gold nanostructures, magnetic nanoparticles, carbon-based materials, quantum dots, and silica nanoparticles will be highlighted. The recent progress of these O/I hybrids in advanced modalities for combating cancer, such as, therapeutic agent delivery, photothermal therapy, photodynamic therapy, and immunotherapy will be systematically reviewed.

4.
BMC Endocr Disord ; 21(1): 225, 2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34774043

RESUMO

BACKGROUND: Prolactinoma is the major cause of hyperprolactinemia, and dopamine agonists (DAs) are generally the first-line treatment for them. Several studies have reviewed the recurrent rate of hyperprolactinemia after DAs withdrawal. However, few of them have concerned the recurrence risk of prolactinoma following the withdrawal of DAs. METHODS: Three medical databases, PubMed, EMBASE and Cochrane library, were retrieved up to February, 14, 2021 to identify studies related to recurrence of prolactinoma and withdrawal of DAs. Statistical analyses including meta-analysis, sensitivity analysis, meta-regression, funnel plot and Egger test were performed through software R. RESULTS: A total of 3225 studies were retrieved from the three data bases, and 13 studies consisted of 616 patients and 19 arms were finally included in this systematic analysis. There was no significant heterogeneity among the included studies, and fixed effect model was thus used. The pooled recurrence proportion of prolactinoma after withdrawal of DA was 2% with a 95% confidence interval (CI) of 1-3%. CONCLUSION: Our study showed a very low recurrent rate of prolactinomas after DAs withdrawal. Much more prospective studies with larger cases and longer follow-up period are encouraged to confirm our finding. TRIAL REGISTRATION: Registration number CRD42021245888 (PROSPERO).

5.
J Sci Food Agric ; 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34628644

RESUMO

BACKGROUND: Fructooligosaccharides (FOS) have been identified as important prebiotics. Previous studies have found that they can significantly promote the proliferation of Bifidobacterium pseudolongum in the mouse intestine. However, it is still unclear which other bacteria in the mouse intestine can utilize FOS, and the differences in the ability to utilize FOS. In this study, the bacteria capable of utilizing FOS were isolated from mice feces and their ability to utilize FOS was compared. Draft genome sequencing was also applied to explain the differences in FOS utilization at the gene levels. RESULTS: A total of 15 species were isolated from mouse feces and 13 species were able to utilize fructofuranosylnystose (GF2). Eleven species could utilize nistose (GF3), but not Enterococcus hirae and Lactobacillus reuteri. In contrast, 1-kestose (GF4) was hardly utilized. The enzyme activity determination and draft genome sequencing-based analyses revealed that all isolated species used the phosphotransferase system or permease system to transport FOS into the cells before hydrolysis by ß-fructofuranosidase. Although ß-fructofuranosidase exists in all strains, there are big differences in the corresponding coding genes between bifidobacteria and non-bifidobacteria. CONCLUSION: Compared with the other isolates, Bifidobacterium species exhibited higher enzyme activity and shorter generation time, leading to a stronger ability to utilize FOS. © 2021 Society of Chemical Industry.

6.
Cells ; 10(9)2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34571896

RESUMO

Stress granules are conserved cytosolic ribonucleoprotein (RNP) compartments that undergo dynamic assembly and disassembly by phase separation in response to stressful conditions. Gene mutations may lead to aberrant phase separation of stress granules eliciting irreversible protein aggregations. A selective autophagy pathway called aggrephagy may partially alleviate the cytotoxicity mediated by these protein aggregates. Cells must perceive when and where the stress granules are transformed into toxic protein aggregates to initiate autophagosomal engulfment for subsequent autolysosomal degradation, therefore, maintaining cellular homeostasis. Indeed, defective aggrephagy has been causally linked to various neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). In this review, we discuss stress granules at the intersection of autophagy and ALS pathogenesis.


Assuntos
Esclerose Amiotrófica Lateral/patologia , Grânulos Citoplasmáticos/patologia , Macroautofagia , Esclerose Amiotrófica Lateral/etiologia , Animais , Humanos
7.
Front Genet ; 12: 697294, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34306037

RESUMO

Manipulation of genes involved in starch synthesis could significantly affect wheat grain weight and yield. The starch-branching enzyme (SBE) catalyzes the formation of branch points by cleaving the α-1,4 linkage in polyglucans and reattaching the chain via an α-1,6 linkage. Three types of SBE isoforms (SBEI, SBEII, and SBEIII) exist in higher plants, with the number of SBE isoforms being species-specific. In this study, the coding sequence of the wheat TaSBEIII gene was amplified. After the multiple sequence alignment of TaSBEIII genome from 20 accessions in a wheat diversity panel, one SNP was observed in TaSBEIII-A, which formed the allelic marker allele-T. Based on this SNP at 294 bp (C/T), a KASP molecular marker was developed to distinguish allelic variation among the wheat genotypes for thousand grain weight (TGW). The results were validated using 262 accessions of mini core collection (MCC) from China, 153 from Pakistan, 53 from CIMMYT, and 17 diploid and 18 tetraploid genotypes. Association analysis between TaSBEIII-A allelic variation and agronomic traits found that TaSBEIII-A was associated with TGW in mini core collection of China (MCC). The accessions possessing Allele-T had higher TGW than those possessing Allele-C; thus, Allele-T was a favorable allelic variation. By analyzing the frequency of the favorable allelic variation Allele-T in MCC, it increased from pre-1950 (25%) to the 1960s (45%) and increased continuously from 1960 to 1990 (80%). The results suggested that the KASP markers can be utilized in grain weight improvement, which ultimately improves wheat yield by marker-assisted selection in wheat breeding. The favorable allelic variation allele-T should be valuable in enhancing grain yield by improving the source and sink simultaneously. Furthermore, the newly developed KASP marker validated in different genetic backgrounds could be integrated into a breeding kit for screening high TGW wheat.

8.
Int J Biol Sci ; 17(8): 1925-1939, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34131396

RESUMO

Background: Angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) allow entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into host cells and play essential roles in cancer therapy. However, the functions of ACE2 and TMPRSS2 in kidney cancer remain unclear, especially as kidneys are targets for SARS-CoV-2 infection. Methods: UCSC Xena project, the Cancer Genome Atlas (TCGA), and Gene Expression Omnibus (GEO) databases (GSE30589 and GSE59185) were searched for gene expression in human tissues, gene expression data, and clinical information. Several bioinformatics methods were utilized to analyze the correlation between ACE2 and TMPRSS2 with respect to the prognosis of kidney renal clear cell carcinoma (KIRC) and kidney renal papillary cell carcinoma (KIRP). Results: ACE2 expression was significantly upregulated in tumor tissue, while its downregulation was associated with low survival in KIRC and KIRP patients. TMPRSS2 was downregulated in KIRC and KIRP, and its expression was not correlated with patient survival. According to clinical risk factor-based prediction models, ACE2 exhibits predictive accuracy for kidney cancer prognosis and is correlated with metabolism and immune infiltration. In an animal model, ACE2 expression was remarkably downregulated in SARS-CoV-2-infected cells compared to in the control. Conclusion: ACE2 expression is highly correlated with various metabolic pathways and is involved in immune infiltration.it plays a crucial role than TMPRSS2 in diagnosing and prognosis of kidney cancer patients. The overlap in ACE2 expression between kidney cancer and SARS-CoV-2 infection suggests that patients with KIRC or KIRP are at high risk of developing serious symptoms.


Assuntos
Enzima de Conversão de Angiotensina 2/biossíntese , COVID-19/complicações , Carcinoma de Células Renais/complicações , Neoplasias Renais/complicações , Receptores Virais/biossíntese , SARS-CoV-2 , Adulto , Idoso , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/fisiologia , Animais , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/mortalidade , Chlorocebus aethiops , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos , Feminino , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Estimativa de Kaplan-Meier , Neoplasias Renais/imunologia , Neoplasias Renais/metabolismo , Neoplasias Renais/mortalidade , Linfócitos do Interstício Tumoral/imunologia , Masculino , Pessoa de Meia-Idade , Modelos Animais , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Especificidade de Órgãos , Prognóstico , Modelos de Riscos Proporcionais , Receptores Virais/genética , Sistema Renina-Angiotensina/fisiologia , Serina Endopeptidases/biossíntese , Serina Endopeptidases/genética , Serina Endopeptidases/fisiologia , Análise Serial de Tecidos , Células Vero
9.
Front Genet ; 12: 623419, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093638

RESUMO

Blast is caused by the host-specific lineages of the fungus Magnaporthe oryzae and is the most important destructive disease in major crop plants, including rice and wheat. The first wheat blast outbreak that occurred in Bangladesh in 2016 and the recent epidemic in Zambia were caused by the M. oryzae Triticum (MoT) pathotype, a fungal lineage belonging to M. oryzae. Although a few reported wheat cultivars show modest resistance to MoT, the patterns of genetic variation and diversity of this pathotype make it crucial to identify additional lines of resistant wheat germplasm. Nearly 40 rice blast resistant and susceptible genes have so far been cloned. Here, we used BLAST analysis to locate two rice blast susceptible genes in the wheat reference genome, bsr-d1 and bsr-k1, and identified six identical homologous genes located on subgenomes A, B, and D. We uncovered a total of 171 single nucleotide polymorphisms (SNPs) in an ethyl methanesulfonate (EMS)-induced population, with mutation densities ranging from 1/1107.1 to 1/230.7 kb through Targeting Induced Local Lesions IN Genomes (TILLING) by sequencing. These included 81 SNPs located in exonic and promoter regions, and 13 coding alleles that are predicted to have severe effects on protein function, including two pre-mature mutants that might affect wheat blast resistance. The loss-of-function alleles identified in this study provide insights into new wheat blast resistant lines, which represent a valuable breeding resource.

10.
Chemistry ; 27(41): 10657-10665, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-33876453

RESUMO

Increasing the metal loading and downsizing the metal particle size are two effective ways to boost the electrochemical performance of catalysts. However, it is difficult to simultaneously increase the metal loading and reduce the particle size since isolated individual atoms are easy to aggregate into nanoparticles when increasing the metal loading. To tackle this contradiction, we report a bottom-up ligand-mediated strategy to facilely prepare ultrafine CoOx nanoclusters anchored on a Co-N-containing carbon matrix (CoOx @Co-NC). The co-exist of N and O atoms prevent Co atoms agglomerating into large particles and allowing the formation of ultrafine dispersed Co species with large Co loading (up to 20 wt.%). Since the relationship between ultrasmall size and large metal loading is well balanced, the CoOx nanoclusters have no inhibitory effect, but facilitate the catalytic performance of Co-N4 sites during OER process. Consequently, due to the synergistic effect of ultrafine CoOx nanoclusters and Co-N4 macrocycles, the as-synthesized CoOx @Co-NC exhibit promising OER activity (η10 =370 mV, Tafel plot=40 mV/dec), bettering than that of benchmark RuO2 (η10 =411 mV, Tafel plot=72 mV/dec). This ligand-mediated strategy to synthesize carbonaceous materials containing dual active centers with large metal loading is promising for developing active and stable catalysts for electrocatalytic applications.

11.
J Sci Food Agric ; 101(13): 5721-5729, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33650140

RESUMO

BACKGROUND: Lactulose was one of the earliest prebiotics to be identified. To assess the potential risk of large intakes of lactulose to the intestinal microbiota, mice were fed a diet containing lactulose (0%, 5% and 15%, w/w) for 2 weeks and the changes in the fecal microbiota were evaluated by 16S rRNA high-throughput sequencing. RESULTS: Lactulose intervention decreased the α-diversity of the fecal microbiota in both low-dose and high-dose groups. The relative abundance of Actinobacteria was significantly increased, while that of Bacteroidetes was significantly decreased after lactulose intervention. At the genus level, the relative abundance of Bifidobacterium belonging to Actinobacteria was significantly increased, and that of Alistipes belonging to Bacteroidetes was decreased in both low-dose and high-dose groups. The relative abundance of Blautia was significantly increased from 0.2% to 7.9% in the high-dose group and one strain of Blautia producta was isolated from the mice feces. However, the strain could not utilize lactulose. CONCLUSION: Overall, the microbial diversity was decreased after lactulose treatment, with significant increases in the relative abundance of Bifidobacterium. We also provide a strategy to increase the relative abundance of Blautia in the intestine by lactulose feeding at high doses, although the mechanism is not revealed. This will help us understand the prebiotic effect of lactulose on the host health. © 2021 Society of Chemical Industry.


Assuntos
Bactérias/isolamento & purificação , Bifidobacterium/crescimento & desenvolvimento , Clostridiales/crescimento & desenvolvimento , Fezes/microbiologia , Microbioma Gastrointestinal , Lactulose/metabolismo , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bifidobacterium/metabolismo , Clostridiales/metabolismo , DNA Bacteriano/genética , Intestinos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Prebióticos/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
12.
Front Plant Sci ; 12: 628478, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33708233

RESUMO

Agronomic traits such as heading date (HD), plant height (PH), thousand grain weight (TGW), and spike length (SL) are important factors affecting wheat yield. In this study, we constructed a high-density genetic linkage map using the Wheat55K SNP Array to map quantitative trait loci (QTLs) for these traits in 207 recombinant inbred lines (RILs). A total of 37 QTLs were identified, including 9 QTLs for HD, 7 QTLs for PH, 12 QTLs for TGW, and 9 QTLs for SL, which explained 3.0-48.8% of the phenotypic variation. Kompetitive Allele Specific PCR (KASP) markers were developed based on sequencing data and used for validation of the stably detected QTLs on chromosomes 3A, 4B and 6A using 400 RILs. A QTL cluster on chromosome 4B for PH and TGW was delimited to a 0.8 Mb physical interval explaining 12.2-22.8% of the phenotypic variation. Gene annotations and analyses of SNP effects suggested that a gene encoding protein Photosynthesis Affected Mutant 68, which is essential for photosystem II assembly, is a candidate gene affecting PH and TGW. In addition, the QTL for HD on chromosome 3A was narrowed down to a 2.5 Mb interval, and a gene encoding an R3H domain-containing protein was speculated to be the causal gene influencing HD. The linked KASP markers developed in this study will be useful for marker-assisted selection in wheat breeding, and the candidate genes provide new insight into genetic study for those traits in wheat.

13.
Gut Microbes ; 13(1): 1-21, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33525961

RESUMO

Blautia is a genus of anaerobic bacteria with probiotic characteristics that occur widely in the feces and intestines of mammals. Based on phenotypic and phylogenetic analyses, some species in the genera Clostridium and Ruminococcus have been reclassified as Blautia, so to date, there are 20 new species with valid published names in this genus. An extensive body of research has recently focused on the probiotic effects of this genus, such as biological transformation and its ability to regulate host health and alleviate metabolic syndrome. This article reviews the origin and biological characteristics of Blautia and the factors that affect its abundance and discusses its role in host health, thus laying a theoretical foundation for the development of new functional microorganisms with probiotic properties.

14.
Front Genet ; 12: 623861, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33633784

RESUMO

The stems of cereal crops provide both mechanical support for lodging resistance and a nutrient supply for reproductive organs. Elongation, which is considered a critical phase for yield determination in winter wheat (Triticum aestivum L.), begins from the first node detectable to anthesis. Previously, we characterized a heavy ion beam triggered wheat mutant qd, which exhibited an altered stem elongation pattern without affecting mature plant height. In this study, we further analyzed mutant stem developmental characteristics by using transcriptome data. More than 40.87 Mb of clean reads including at least 36.61 Mb of unique mapped reads were obtained for each biological sample in this project. We utilized our transcriptome data to identify 124,971 genes. Among these genes, 4,340 differentially expressed genes (DEG) were identified between the qd and wild-type (WT) plants. Compared to their WT counterparts, qd plants expressed 2,462 DEGs with downregulated expression levels and 1878 DEGs with upregulated expression levels. Using DEXSeq, we identified 2,391 counting bins corresponding to 1,148 genes, and 289 of them were also found in the DEG analysis, demonstrating differences between qd and WT. The 5,199 differentially expressed genes between qd and WT were employed for GO and KEGG analyses. Biological processes, including protein-DNA complex subunit organization, protein-DNA complex assembly, nucleosome organization, nucleosome assembly, and chromatin assembly, were significantly enriched by GO analysis. However, only benzoxazinoid biosynthesis pathway-associated genes were enriched by KEGG analysis. Genes encoding the benzoxazinoid biosynthesis enzymes Bx1, Bx3, Bx4, Bx5, and Bx8_9 were confirmed to be differentially expressed between qd and WT. Our results suggest that benzoxazinoids could play critical roles in regulating the stem elongation phenotype of qd.

15.
Am J Cancer Res ; 11(2): 458-478, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33575081

RESUMO

Activation of the cyclic adenosine monophosphate (cAMP) pathway induces the glial differentiation of glioblastoma (GBM) cells, but the fate of differentiated cells remains poorly understood. Transcriptome analyses have revealed significant changes in the cell cycle- and senescence-related pathways in differentiated GBM cells induced by dibutyryl cAMP (dbcAMP). Further investigations showed that reactive oxygen species (ROS) derived from enhanced mitochondrial function are involved in senescence induction and proliferation inhibition. Moreover, we found that IL-6 from dbcAMP- or temozolomide (TMZ)-induced senescent cells facilitates the glycolytic phenotype of GBM cells and that inhibiting the IL-6-related pathway hinders the proglycolytic effect of either agent. In patient-derived GBM xenograft models, a specific antibody targeting the IL-6 receptor tocilizumab (TCZ) significantly prolongs the survival time of TMZ-treated mice. Taken together, these results suggest that both the differentiation-inducing agent dbcAMP and the chemotherapy drug TMZ are able to drive GBM cells to senescence, and the latter releases IL-6 to potentiate glycolysis, suggesting that IL-6 is a target for adjuvant chemotherapy in GBM treatment.

16.
Food Chem ; 343: 128497, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33160771

RESUMO

The stability and bioavailability of fourteen astaxanthin esters (Asta-Es) with different molecular structures were investigated using in vitro and in vivo digestion models. The results demonstrated that Asta-E with long-chain and saturated fatty acids were more stable than other types of Asta-E. Astaxanthin diester (Asta-DE) was better than astaxanthin monoester (Asta-ME) and free astaxanthin (F-Asta), as determined based on the degradation rate constant at 60 °C. The absorbability of Asta-Es with different molecular structures was evaluated through the serum concentrations of astaxanthin (Asta). The results indicated that Asta-E with short-chain fatty acids had higher bioavailability than Asta-Es with long-chain fatty acids, whereas Asta-E with high-unsaturation fatty acids had higher bioavailability than Asta-E with low-unsaturation fatty acids. Asta-ME had significantly increased bioavailability compared with Asta-DE. We concluded that the molecular structure of Asta-E could significantly affect their stability and bioavailability.


Assuntos
Ésteres/química , Disponibilidade Biológica , Estabilidade de Medicamentos , Ácidos Graxos/química , Estrutura Molecular , Xantofilas/química , Xantofilas/farmacocinética
17.
J Sci Food Agric ; 101(5): 1758-1766, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32892354

RESUMO

BACKGROUND: Lactobacillus plantarum is an important probiotic with a variety of physiologic functions. Studies have focused on the effects of L. plantarum on host physiology and microbiota, but studies of the fate of strains after they enter the intestine are lacking. In this study, L. plantarum ST-III was genetically engineered to express green fluorescent protein (GFP). Mice were administered ST-III-GFP, and fluorescence imaging was used to study the distribution, location and quantity of strains within 8 h after entry into the intestine. RESULTS: The results indicated that genetic modification did not affect the growth of ST-III, tolerance to simulated gastric juice and intestinal fluid or tolerance to antibiotics (with the exception of chloramphenicol). Fluorescence imaging and colony counting indicated that ST-III-GFP can be detected in the small intestine 5 min after oral gavage. After 30 min, nearly all ST-III-GFP was located in the small intestine. After 1.5 h, ST-III-GFP was detected in both the cecum and large intestine. After 4 and 8 h, ST-III-GFP was mainly concentrated in the cecum and large intestine. Compared to the initial amount ingested, the survival rate of ST-III-GFP within the intestine of mice was 10% after 8 h. In addition, a strong linear relationship was found between the fluorescence intensity and the viable count of ST-III-GFP. CONCLUSIONS: The obtained data indicate that the amount of ST-III-GFP can be estimated by measuring the fluorescence intensity of this novel strain within the intestinal tract. © 2020 Society of Chemical Industry.


Assuntos
Rastreamento de Células/métodos , Proteínas de Fluorescência Verde/química , Intestinos/microbiologia , Lactobacillus plantarum/química , Imagem Óptica/métodos , Probióticos/química , Animais , Contagem de Colônia Microbiana , Fluorescência , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Lactobacillus plantarum/genética , Lactobacillus plantarum/crescimento & desenvolvimento , Lactobacillus plantarum/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
18.
J Sci Food Agric ; 101(4): 1609-1617, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32875593

RESUMO

BACKGROUND: Astaxanthin ester (Asta-E) is used as functional nutraceuticals in many food products. Unfortunately, Asta-E utilization is currently limited owing to its chemical instability and low bioavailability. The purpose of this study is to investigate the promotion effect of oil matrixes on the stability, antioxidant activity, bioaccessibility and bioavailability of Asta-E. RESULTS: The results showed that the stability of Asta-E in six oil matrixes was improved. Based on the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity experiment, the antioxidant activity of Asta-E was positively correlated with the degree of unsaturation of the oil matrixes, but not with the side chain length. The in vitro gastrointestinal tract (GIT) simulation model and in vivo experiment using mice were also employed to investigate the digestion and absorption characteristics of Asta-E in various oil matrixes. The results demonstrated that the bioaccessibility and bioavailability of Asta-E increased with the increase of fatty acid chain length of oil matrixes (triglyceride oleate > triglyceride caprylate > triglyceride butyrate), as well as with the decrease of unsaturation degree (olive oil > corn oil > fish oil). CONCLUSION: Monounsaturated fatty acids (MUFA) and long-chain triglyceride (LCT) in an oil matrix were the factors that could efficiently improve the bioavailability of Asta-E. Moreover, the size of the mixed micelles of Asta-E during digestion was the main factor influencing the bioaccessibility of Asta-E. This study provides references for the design of suitable oil matrixes for Asta-E. © 2020 Society of Chemical Industry.


Assuntos
Antioxidantes/química , Portadores de Fármacos/química , Ésteres/química , Óleos/química , Animais , Antioxidantes/metabolismo , Disponibilidade Biológica , Digestão , Estabilidade de Medicamentos , Ésteres/metabolismo , Trato Gastrointestinal/metabolismo , Camundongos , Xantofilas/química , Xantofilas/metabolismo
19.
Food Chem ; 335: 127633, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32739813

RESUMO

The influence of different fatty acid carbon chains on the kinetic interactions of nanocomplexes between esterified astaxanthin (E-Asta) and ß-lactoglobulin (ß-Lg) were investigated by multi-spectroscopy and molecular modeling techniques. We synthesized ten different E-Asta bound to ß-Lg and formed nanocomplexes (< 300 nm). Fluorescence spectroscopy showed moderate affinities (binding constants Ka = 103-104 M-1). Docosahexaenoic acid astaxanthin monoester (Asta-C22:6) had the strongest binding affinity towards ß-Lg (Ka = 3.77 × 104 M-1). The fluorescence quenching of ß-Lg upon binding of E-Asta displayed a static mechanism, with binding sites (n) equal to 1. Fourier transform infrared spectroscopy and ultraviolet-visible absorption spectroscopy revealed that E-Asta might enter the ß-Lg hydrophobic cavity, leading to unfolding of the peptide chain skeleton. In summary, ß-Lg and E-Asta can form stable nanocomplex emulsions to achieve an effective delivery process for E-Asta.


Assuntos
Ésteres/química , Lactoglobulinas/química , Nanoestruturas/química , Sítios de Ligação , Interações Hidrofóbicas e Hidrofílicas , Cinética , Xantofilas/química
20.
Biotechnol Adv ; 46: 107679, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33316366

RESUMO

Ethanol-type fermentation (ETF) is one of three fermentation types during the acidogenesis of the anaerobic biological treatment. Ethanoligenens, a representative genus of ETF, displays acidophilic, autoaggregative, and ethanol-H2 co-producing characteristics and facilitates subsequent methanogenesis. Here, the latest advances in the molecular mechanisms of the metabolic regulation of ethanol-H2 co-producing bacteria based on multi-omics studies were comprehensively reviewed. Comparative genomics demonstrated a low genetic similarity between Ethanoligenens and other hydrogen-producing genera. FeFe­hydrogenases (FeFe-H2ases) and pyruvate ferredoxin oxidoreductase (PFOR) played critical roles in the ethanol-H2 co-metabolic pathway of Ethanoligenens. Global transcriptome analysis revealed that highly expressed [FeFe]-H2ases and ferredoxins drove hydrogen production by Ethanoligenens at low pH conditions (4.0-4.5). Quantitative proteomic analysis also proved that this genus resists acetic acid-induced intracellular acidification through the up-regulated expression of pyrimidine metabolism related proteins. The autoaggregation of Ethanoligenen facilitated its granulation with acetate-oxidizing bacteria in co-culture systems and mitigated a fast pH drop, providing a new approach for solving a pH imbalance and improving hydrogen production. In-depth studies of the regulatory mechanism underlying ethanol-H2 co-production metabolism and the syntrophic interactions of ethanol-H2 co-producing Ethanoligenens with other microorganisms will provide insights into the improvement of bioenergy recovery in anaerobic biotechnology. The coupling of ETF with other biotechnologies, which based on the regulation of electron flow direction, syntrophic interaction, and metabolic flux, can be potential strategies to enhance the cascade recovery of energy and resources.


Assuntos
Etanol , Proteômica , Anaerobiose , Fermentação , Hidrogênio
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