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1.
Opt Lett ; 48(3): 799-802, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36723592

RESUMO

We demonstrate the first multi-segmented Nd:YLF laser, to the best of our knowledge. The multi-segmented crystal was designed to straightforwardly aim for the minimum thermal stress without sacrificing the overall laser efficiency, with the influence of the pump beam waist position considered in particular. Integrating the enhanced thermo-mechanical resistance of multi-segmented crystal and the alleviated heat load of low quantum defect pumping, this end-pumped 1314 nm Nd:YLF laser system delivered a maximum continuous-wave output power of up to 35.5 W under a pump power of 105 W, corresponding to an optical-to-optical efficiency of 33.8%. Furthermore, by incorporating an acousto-optic modulator, an active Q-switching oscillator was accomplished, yielding a maximum average output power of 22.9 W at a pulse repetition frequency (PRF) of 20 kHz and a largest pulse energy of 13.6 mJ at a PRF of 1 kHz.

2.
J Sci Food Agric ; 102(14): 6737-6748, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35621360

RESUMO

BACKGROUND: Cadmium is a non-biodegradable heavy metal with a long biological half-life. Although its negative impact on human health has been previously reported, the association of cadmium consumption overdose with changes in the gut microbiota and its corresponding metabolites has not been fully elucidated so far. RESULTS: Cadmium consumption overdose led to a reduced body weight gain accompanied by an enhanced level of the proinflammatory cytokine tumor necrosis factor-α, interleukin-6, and histamine in the serum of the rats in comparison with normal rats. Furthermore, hepatotoxicity was also observed to be induced by cadmium, which was consistent with abnormal hepatic activities of alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase and oxidative stress. In contrast, Lactobacillus rhamnosus-fermented Ganoderma lucidum (FGL) slice supplementation improved the aforementioned physiological properties. More importantly, microbiome and metabolites analysis indicated cadmium exposure significantly reduced the generation of short-chain fatty acids in the gut, particularly butyrate. However, rats in the FGL group had the highest level of butyrate in the feces, characterized with significantly enriched probiotics (Lactobacillus, Bifidobacterium) and butyrate-producing bacteria (Roseburia). CONCLUSION: The targeted regulation of the gut microbial community and its metabolites might be the essential association for attenuating body dysfunction induced by cadmium. The supplementation of FGL, as evidenced in this study, might highlight a novel approach to this field. © 2022 Society of Chemical Industry.


Assuntos
Microbioma Gastrointestinal , Probióticos , Alanina Transaminase , Fosfatase Alcalina , Animais , Aspartato Aminotransferases , Butiratos/análise , Cádmio/análise , Ácidos Graxos Voláteis/metabolismo , Fezes/microbiologia , Histamina/análise , Humanos , Interleucina-6 , Probióticos/farmacologia , Ratos , Fator de Necrose Tumoral alfa
3.
J Food Sci Technol ; 57(1): 375-380, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31975740

RESUMO

The study was undertaken to investigate the comparison lying between bacterial communities in autochthonous gliadin-degraded sourdough sample (D13) and non-degraded sample (D50). Degree of gliadin degradation in various samples was determined by Fourier transform infrared spectroscopy and represented samples were selected for 16 S rDNA sequence analysis by Illumina Miseq platform. It was observed, that Proteobacteria (50.65%) and Actinobacteria (6.70%) phyla were more abundant as compared with Firmicutes (42.53%) in D13, however, Firmicutes (83.44) were more abundant, comparatively, in D50 than Proteobacteria (14.97%). Lower taxonomic levels surfaced its more prominent effects. It had been also observed that Lactobacillus genera was the core genera (50.37%) followed by Weissella (27.15%) and Psychrobacter (21.53%) in D50 and D13, respectively. Shannon and Simpson indices indicated that degraded sample had more bacterial diversity and richness compared with non-degraded sample.

4.
Cutan Ocul Toxicol ; 37(1): 96-99, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28707485

RESUMO

OBJECTIVE: This study presented common lesions with systemic toxicities and uncommon adverse cutaneous reactions such as anaphylactic dermatitis in patients undergoing treatment with erlotinib for the benefit of practicing dermatologists and oncologists. METHODS: Adverse cutaneous reactions associated with erlotinib were reported in 20 Chinese patients with cancer. RESULTS: Adverse cutaneous reactions reported included six cases of anaphylactic dermatitis, 12 cases of acneiform rash, nine cases of xerosis, five cases of nail changes and four cases of hair changes. One case of anaphylactic dermatitis manifested as erythema with swelling on the face and neck, and others as erosive and scaly erythema on the fold of skin, or red macules, papules, plaques and pigmentation on the whole body. Clinical details indicated anaphylactic reactions, including a high percentage of eosinophils in the peripheral blood, eosinophilic infiltration in the dermis layer and good response to antihistamines and topical steroids. Systemic toxicities accompanied by cutaneous reactions occurred in five patients including one case of anaphylactic dermatitis and four cases of acneiform rash. Elevated hepatic enzymes were observed among all the patients with grade-3 or grade-4 acneiform rashes. One patient with anaphylactic dermatitis and one with acneiform rash discontinued erlotinib administration due to severe lesions, high fever or severe elevation of hepatic enzymes. CONCLUSIONS: Anaphylactic cutaneous reactions caused by erlotinib are rarely described hitherto. Systemic toxicities should be emphasized especially in cases with severe skin disorders. Timely detection and appropriate early intervention in patients who develop severe cutaneous reaction while on erlotinib therapy should be considered clinically.


Assuntos
Anafilaxia/induzido quimicamente , Antineoplásicos/efeitos adversos , Cloridrato de Erlotinib/efeitos adversos , Inibidores de Proteínas Quinases/efeitos adversos , Dermatopatias/induzido quimicamente , Adulto , Idoso , Antineoplásicos/uso terapêutico , Povo Asiático , Cloridrato de Erlotinib/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico
5.
Chemistry ; 22(28): 9768-76, 2016 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-27246459

RESUMO

Molecular mechanisms underlying the repair of nitrosylated [Fe-S] clusters by the microbial protein YtfE remain poorly understood. The X-ray crystal structure of YtfE, in combination with EPR, magnetic circular dichroism (MCD), UV, and (17) O-labeling electron spin echo envelope modulation measurements, show that each iron of the oxo-bridged Fe(II) -Fe(III) diiron core is coordinatively unsaturated with each iron bound to two bridging carboxylates and two terminal histidines in addition to an oxo-bridge. Structural analysis reveals that there are two solvent-accessible tunnels, both of which converge to the diiron center and are critical for capturing substrates. The reactivity of the reduced-form Fe(II) -Fe(II) YtfE toward nitric oxide demonstrates that the prerequisite for N2 O production requires the two iron sites to be nitrosylated simultaneously. Specifically, the nitrosylation of the two iron sites prior to their reductive coupling to produce N2 O is cooperative. This result suggests that, in addition to any repair of iron centers (RIC) activity, YtfE acts as an NO-trapping scavenger to promote the NO to N2 O transformation under low NO flux, which precedes nitrosative stress.


Assuntos
Ferro/química , Metaloproteínas/química , Óxido Nítrico/química , Dicroísmo Circular , Cristalografia por Raios X , Metaloproteínas/metabolismo , Modelos Moleculares , Óxido Nítrico/metabolismo
6.
J Food Sci Technol ; 53(2): 1178-88, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27162397

RESUMO

Effect of transglutaminase (TGM) and ascorbic acid (AA) on composite sweet potato - wheat dough functional and rheological properties was studied. Partial substitution of wheat flour with sweet potato flour at the level of 20 % significantly (P ≤ 0.05) reduced glutenin, gliadin, dough stability, protein weakening, storage modulus (G') and viscous modulus (G″). Mixolab revealed that both TGM and AA treated dough had stability and protein weakening closed to wheat dough (control), with TGM treated dough having the highest values. TGM Introduced new cross-link bonds as shown by the change of amino acid concentration, leading to an increase in storage modulus (G') and viscous modulus (G″), with G' being higher at all levels of TGM concentration. The opposite was observed for composite dough treated with AA as measured by controlled - stress rheometer. TGM treatment increased glutenin and gliadin content. Compared with the control, dough treated with AA exhibited high molecular weight of polymers than TGM treated dough. The results indicate that the TGM and AA modification of the mixolab and dynamic rheological characteristics (G' and G″) dependent on the changes of GMP, glutenin, gliadin and protein weakening in the composite dough. TGM and AA treatment could improve functional and rheological properties of sweet potato - wheat dough to levels that might be achieved with normal wheat bread. However, it's extremely important to optimize the concentrations of both additives to obtain the optimum response.

7.
Artigo em Inglês | MEDLINE | ID: mdl-26460924

RESUMO

OBJECTIVE: To investigate the source of snoring sound in patients with simple snoring (SS) and different degrees of obstructive sleep apnea syndrome (OSAS) in order to provide a basis for the surgical treatment of snoring. METHODS: Fifty-two patients with either SS or OSAS (with an apnea-hypopnea index ≤40) underwent drug-induced sleep nasendoscopy (DISN). Vibration sites in the pharyngeal cavity were observed. RESULTS: Vibration of the soft palate, pharyngeal lateral wall, epiglottis, and tongue base appeared in 100, 53.8, 42.3, and 26.9% of the patients, respectively. The source of snoring sound was divided into two types: palatal fluttering only (type I) and multisite vibration (type II). The latter was divided into 3 subtypes: palatal fluttering with epiglottis vibration (type IIa), palatal fluttering with lateral wall vibration (type IIb), and palatal fluttering with vibration of the lateral wall, epiglottis, and tongue base together (type IIc). The distribution of type I snoring was the highest in SS patients. Type IIb was more common in patients with medium and severe OSAS. Type IIc was most common in patients with severe OSAS. CONCLUSION: The source of snoring sound is diverse, with SS and OSAS patients showing different features. DISN is a very effective method of identifying the snoring source.


Assuntos
Endoscopia/métodos , Palato/fisiopatologia , Sono/fisiologia , Ronco/diagnóstico , Língua/fisiopatologia , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Nariz , Palato/efeitos dos fármacos , Polissonografia , Estudos Retrospectivos , Ronco/etiologia , Língua/efeitos dos fármacos , Adulto Jovem
8.
Heliyon ; 10(13): e33742, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39027568

RESUMO

Introduction: Membranous aplasia cutis congenita (MACC) is the most common clinical subtype of aplasia cutis congenita (ACC). It is typified by a localized skin lesion devoid of hair and features a membranous surface. While most MACC individuals do not present with concurrent abnormalities, it can sometimes co-occur with additional physical anomalies and various malformation syndromes. Moreover, the underlying causes of MACC remain elusive. Case presentation: We describe a case of a 6-month-old female infant diagnosed with MACC. The patient presented with a midline skin lesion on the occipital scalp, characterized by a glistening surface and a hair collar sign. Dermoscopic examination revealed specific features, including translucency, telangiectasia, and hypertrichosis. The infant had a history of patent foramen ovale, and further examination uncovered an asymptomatic ventricular septal defect. Whole exome sequencing revealed 20 gene variants relevant to the clinical phenotype of the patient, suggesting a possible association with MACC. Conclusion: MACC is a rare and underreported condition, primarily diagnosed based on its distinctive clinical features. It is imperative to emphasize the significance of thorough evaluations in MACC patients, encompassing developmental, cardiac, neurological, and genetic assessments to facilitate early detection and the exclusion of potentially life-threatening comorbidities. Importantly, genetic characterization, as demonstrated in this case, contributes to our understanding of MACC's etiology and highlights the need for further research in this field.

9.
Int J Biol Macromol ; 271(Pt 1): 132434, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38788879

RESUMO

The aim of this study was to improve the inhibitory resistance of xylanase FgXyn11C from Fusarium graminearum to XIP in cereal flour. Site saturation mutagenesis was performed using computer-aided redesign. Firstly, based on multiple primary structure alignments, the amino acid residues in the active site architecture were identified, and specific residue T144 in the thumb region of FgXyn11C was selected for site-saturation mutagenesis. After screening, FgXyn11CT144F was selected as the best mutant, as it displayed the highest enzymatic activity and resistance simultaneously compared to other mutants. The specific activity of FgXyn11CT144F was 208.8 U/mg and it exhibited complete resistance to SyXIP-I. Compared with the wild-type, FgXyn11CT144F displayed similar activity and the most resistant against SyXIP-I. The optimal temperature and pH of the wild-type and purified FgXyn11CT144F were similar at pH 5.0 and 30 °C. Our findings provided preliminary insight into how the specific residue at position 144 in the thumb region of FgXyn11C influenced the enzymatic properties and interacted with SyXIP-I. The inhibition sensitivity of FgXyn11C was reduced through directed evolution, leading to creation of the mutant enzyme FgXyn11CT144F. The FgXyn11CT144F resistance to SyXIP-I has potential application and can also provide references for engineering other resistant xylanases of the GHF11.


Assuntos
Endo-1,4-beta-Xilanases , Fusarium , Mutagênese Sítio-Dirigida , Fusarium/enzimologia , Fusarium/efeitos dos fármacos , Fusarium/genética , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/metabolismo , Endo-1,4-beta-Xilanases/antagonistas & inibidores , Domínio Catalítico , Modelos Moleculares , Concentração de Íons de Hidrogênio , Sequência de Aminoácidos , Temperatura
10.
3 Biotech ; 14(6): 162, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38803445

RESUMO

In order to search for high specific activity and the resistant xylanases to XIP-I and provide more alternative xylanases for industrial production, a strain of Fusarium graminearum from Triticum aestivum grains infected with filamentous fungus produced xylanases was isolated and identified. Three xylanase genes from Fusarium graminearum Z-1 were cloned and successfully expressed in E. coli and P. pastoris, respectively. The specific activities of Fgxyn1, EFgxyn2 and EFgxyn3 for birchwood xylan were 38.79, 0.85 and 243.83 U/mg in E. coli, and 40.11, 0 and 910.37 U/mg in P. pastoris, respectively. EFgxyn3 and PFgxyn3 had the similar optimum pH at 6.0 and pH stability at 5.0-9.0. However, they had different optimum temperature and thermal stability, with 30 °C for EFgxyn3 and 40 °C for PFgxyn3, and 4-35 °C for EFgxyn3 and 4-40 °C for PFgxyn3, respectively. The substrate spectrum and the kinetic parameters showed that the two xylanases also exhibited the highest xylanase activity and catalytic efficiency (kcat/km) toward birchwood xylan, with 243.83 U/mg and 61.44 mL/mg/s for EFgxyn3 and 910.37 U/mg and 910.37 mL/mg/s for PFgxyn3, respectively. This study provided a novel mesophilic xylanase with high specific activity and catalytic efficiency, thus making it a promising candidate for extensive applications in animal feed and food industry. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-024-03973-0.

11.
J Food Sci ; 89(3): 1403-1413, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38282363

RESUMO

A ß-1,3-1,4-glucanase gene (Auglu12A) from Aspergillus usamii was successfully expressed in Escherichia coli BL21(DE3). The recombinant enzyme, reAuglu12A was efficiently purified using the one-step nickel-nitrilotriacetic acid affinity chromatography. The specific activity of reAuglu12A was 694.8 U/mg, with an optimal temperature of 55°C and pH of 5.0. The reAuglu12A exhibited stability at temperatures up to 60°C and within the pH range of 4.0-5.5. The reAuglu12A hydrolytic activity was increased in the presence of metal ions, especially K+ and Na+ , whereas it exhibited a Km and Vmax of 8.35 mg/mL and 1254.02 µmol/min/mg, respectively, toward barley ß-glucan at pH 5.0 and 55°C. The addition of reAuglu12A significantly increased the specific volume (p < 0.05) and reduced crumb firmness and chewiness (p < 0.05) of wheat-barley sourdough bread during a 7-day storage period compared to the control. Overall, the quality of wheat-barley sourdough bread was improved after incorporation of reAuglu12A (especially at 3000 U/300 g). These changes were attributed to the synergistic effect of acidification by sourdough and its metabolites which provided a conducive environment for the optimal action of reAuglu12A in the degradation of ß-glucans of barley flour in sourdough. This stabilized the dough structure, thereby enhancing the quality, texture, and shelf life of the bread. These findings suggest that reAuglu12A holds promise as a candidate for ß-glucanase application in the baking industry.


Assuntos
Aspergillus , Pão , Escherichia coli , Pão/análise , Escherichia coli/genética , Fenômenos Químicos
12.
Biochim Biophys Acta ; 1818(5): 1378-85, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22387431

RESUMO

Cobra CTX A3, the major cardiotoxin (CTX) from Naja atra, is a cytotoxic, basic ß-sheet polypeptide that is known to induce a transient membrane leakage of cardiomyocytes through a sulfatide-dependent CTX membrane pore formation and internalization mechanism. The molecular specificity of CTX A3-sulfatide interaction at atomic levels has also been shown by both nuclear magnetic resonance (NMR) and X-ray diffraction techniques to reveal a role of CTX-induced sulfatide conformational changes for CTX A3 binding and dimer formation. In this study, we investigate the role of sulfatide lipid domains in CTX pore formation by various biophysical methods, including fluorescence imaging and atomic force microscopy, and suggest an important role of liquid-disordered (ld) and solid-ordered (so) phase boundary in lipid domains to facilitate the process. Fluorescence spectroscopic studies on the kinetics of membrane leakage and CTX oligomerization further reveal that, although most CTXs can oligomerize on membranes, only a small fraction of CTXs oligomerizations form leakage pores. We therefore suggest that CTX binding at the boundary between the so and so/ld phase coexistence sulfatide lipid domains could form effective pores to significantly enhance the CTX-induced membrane leakage of sulfatide-containing phosphatidylcholine vesicles. The model is consistent with our earlier observations that CTX may penetrate and lyse the bilayers into small aggregates at a lipid/protein molar ratio of about 20 in the ripple P(ß)' phase of phosphatidylcholine bilayers and suggest a novel mechanism for the synergistic action of cobra secretary phospholipase A2 and CTXs.


Assuntos
Membrana Celular/química , Proteínas Cardiotóxicas de Elapídeos/química , Elapidae , Bicamadas Lipídicas/química , Membranas Artificiais , Multimerização Proteica , Animais , Membrana Celular/metabolismo , Proteínas Cardiotóxicas de Elapídeos/metabolismo , Bicamadas Lipídicas/metabolismo , Miócitos Cardíacos/química , Miócitos Cardíacos/metabolismo , Ressonância Magnética Nuclear Biomolecular , Fosfatidilcolinas/química , Fosfatidilcolinas/metabolismo , Estrutura Secundária de Proteína , Difração de Raios X
13.
Zhonghua Yi Xue Za Zhi ; 93(38): 3040-3, 2013 Oct 15.
Artigo em Zh | MEDLINE | ID: mdl-24417924

RESUMO

OBJECTIVE: To explore the efficacies of nasal cavity enlarging surgery in obstructive sleep apnea hypopnea syndrome (OSAHS) patients with nasal obstruction. METHODS: From April 2011 to October 2012, a total of 22 OSAHS patient with nasal obstruction underwent nasal cavity enlargement. Natural overnight snoring was digitally recorded, polysomnography (PSG) performed simultaneously and nasal resistance measured at pre- and post-operation. Body mass index (BMI), Epworth sleepiness scale (ESS), apnea-hypopnea index (AHI), minimum oxygen saturation SaO2, total nasal resistance, peak frequency, maximal frequency, mean frequency, central frequency and power ratio 800 Hz of snores were recorded and compared. RESULTS: BMI and SaO2 rose while AHI and ESS declined post-operatively. No statistical difference existed between pre-operation and post-operation. The total nasal resistance was (0.39 ± 0.15) and (0.29 ± 0.11) Pa·cm(-3)·s(-1) at pre- and post-operation. And there was significant statistical difference (P < 0.01) . The snores at pre- and post-operation exhibited different patterns in time and power spectrum distribution domains. And fmax, fpeak and fmean declined while fc and PR800 rose at post-operation. Significant statistical differences existed in the change of fpeak and PR800 at pre- and post-operation (P < 0.01) . CONCLUSION: Nasal cavity enlargement can lessen nasal resistance and change the acoustic characteristics of snoring in OSAHS patients. The postoperative snoring focus of lower frequency suggests that acoustic parameters of snores may be used to evaluate the efficacy of OSAHS surgery.


Assuntos
Cavidade Nasal/cirurgia , Procedimentos Cirúrgicos Otorrinolaringológicos , Apneia Obstrutiva do Sono/fisiopatologia , Ronco/cirurgia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Apneia Obstrutiva do Sono/cirurgia , Adulto Jovem
14.
Case Rep Dermatol Med ; 2023: 8475270, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37342426

RESUMO

Chondrocutaneous branchial remnants (CCBRs) are rare congenital heterotopic tissue formations originating from the first or second embryonic branchial arches. Clinically, CCBRs are characterized predominantly by unilateral and solitary cartilaginous nodules found on the lower neck region. Herein, we present a case of CCBRs in a 9-year-old male patient who presented with horn-shaped projecting masses on either side of the anterior border of the sternocleidomastoid muscle. The pathological report following surgical resection revealed that the lesion was located in the dermis and consisted primarily of hyaline cartilage tissue enclosed by a fibrous capsule, with few local vascular proliferations. Based on the clinical and pathological features, the patient was ultimately diagnosed with congenital bilateral cervical chondrocutaneous branchial remnants.

15.
Antioxidants (Basel) ; 12(3)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36978812

RESUMO

Protein particles have been reported as the potential carriers for the co-encapsulation of bioactive components. In this study, lysozyme, a basic protein, was used to simultaneously encapsulate folic acid and α-tocopherol at pH 4.0. The encapsulation efficiency and loading capacity of folic acid or α-tocopherol increased with its respective concentration. Folic acid had no influence on the encapsulation of α-tocopherol. However, the encapsulation of folic acid was improved by α-tocopherol below 40 µg/mL but reduced by α-tocopherol at higher concentrations. The encapsulation by lysozyme shielded folic acid, α-tocopherol, or both partially from the attack of 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) radical cation. No masking effect of lysozyme encapsulation on α-tocopherol was found in DPPH antioxidant activity assay. Furthermore, the DNA coating was used to improve the dispersion of lysozyme with folic acid and α-tocopherol. The lysozyme/DNA particles with folic acid and α-tocopherol showed a homogenous size distribution of 180-220 nm with ζ-potential values between -33 and -36 mV. The release and bioaccessibility of folic acid in lysozyme/DNA with α-tocopherol were similar to that of folic acid alone, while the release of α-tocopherol was delayed and its bioaccessibility was improved by encapsulation in lysozyme/DNA with folic acid. The data gathered here would provide guidance for the use of lysozyme-based co-encapsulating carriers in the development of functional foods.

16.
Foods ; 12(19)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37835228

RESUMO

To reduce the inhibition sensitivity of a thermoresistant xylanase AusM to xylanase inhibitor protein (XIP)-type in wheat flour, the site-directed mutagenesis was conducted based on the computer-aided redesign. First, fourteen single-site variants and one three-amino acid replacement variant in the thumb region of an AusM-encoding gene (AusM) were constructed and expressed in E. coli BL21(DE3), respectively, as predicted theoretically. At a molar ratio of 100:1 between SyXIP-I/xylanase, the majority of mutants were nearly completely inactivated by the inhibitor SyXIP-I, whereas AusMN127A retained 62.7% of its initial activity and AusMPKK retained 100% of its initial activity. The optimal temperature of the best mutant AusMPKK was 60 °C, as opposed to 60-65 °C for AusM, while it exhibited improved thermostability, retaining approximately 60% of its residual activity after heating at 80 °C for 60 min. Furthermore, AusMPKK at a dosage of 1000 U/kg was more effective than AusM at 4000 U/kg in increasing specific bread loaf volume and reducing hardness during bread production and storage. Directed evolution of AusM significantly reduces inhibition sensitivity, and the mutant enzyme AusMPKK is conducive to improving bread quality and extending its shelf life.

17.
Foods ; 12(3)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36766134

RESUMO

This study investigated the impact of in situ-formed exopolysaccharides (EPS) in red bean (Vigna angularis) sourdough fermented by Weissella confusa QS813 on dough rheo-fermentation properties, bread-making quality and aroma characteristics of red bean sourdough bread. The EPS formed in red bean sourdough and sourdough-induced acidification improved the maximum dough fermentation height, gas retention coefficient and viscoelastic properties of dough. Doughs had a lower increase rate of total SDS-soluble gluten proteins, a low decline in GMP content and similar free sulfhydryl content to wheat dough. Resultantly, breads showed declines in baking loss and hardness, increase in specific volume and lower moisture loss and staling rate after 7 days of storage. Finally, despite a reduction in the total content of aroma compounds, new aroma compounds such as acetic acid and higher contents of 3-methyl-1-butanol and 2,3-butanediol were enriched in red bean sourdough bread. Sourdough acidification probably promoted interaction of EPS with gluten or red bean proteins through bond interactions to form structures which stabilized gluten in dough and increased water-binding ability in red bean sourdough bread. This study provided a better understanding of the role of EPS in sourdough in improving bread quality and of promising strategies to address consumer demand for nutritious and clean-label products.

18.
J Agric Food Chem ; 71(13): 5185-5194, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36943701

RESUMO

Antimicrobial peptides (AMPs) play essential roles in maintaining intestinal health and have been suggested as possible therapeutic strategies against inflammatory bowel disease (IBD). However, the instability of AMPs in the process of transmission in vivo limits their application in the treatment of IBD. In this study, we constructed the mBD14-producing Lactococcus lactis NZ9000 (L. lactis/mBD14) to achieve enteric delivery of mBD14 and evaluated its protective effect on dextran sodium sulfate (DSS)-induced colitis. Mice treated with L. lactis/mBD14 exhibited milder symptoms of colitis (P < 0.01). Additionally, L. lactis/mBD14 treatment reversed DSS-induced epithelial dysfunction and reduced the production of pro-inflammatory cytokines in colon (P < 0.01). Mechanistically, L. lactis/mBD14 significantly inhibited NOD-like receptor pyrin domain containing three inflammasome-mediated pro-inflammatory response (P < 0.05) and regulated microbiota homeostasis by promoting the abundance of probiotic bacteria Akkermansia muciniphila and Faecalibacterium prausnitzii and decreasing the pathogenic Escherichia coli (P < 0.01). Taken together, this study demonstrates the protective effect of L. lactis/mBD14 in DSS-induced colitis, and suggests that oral administration of L. lactis/mBD14 may represent a potential therapeutic strategy for IBD.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Lactococcus lactis , beta-Defensinas , Animais , Camundongos , beta-Defensinas/genética , Doenças Inflamatórias Intestinais/terapia , Lactococcus lactis/genética , Colite/induzido quimicamente , Colite/genética , Colite/patologia , Sulfato de Dextrana/efeitos adversos , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
19.
Food Funct ; 14(16): 7413-7425, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37475602

RESUMO

In this study, the effect of mixed-strain fermentation using Kluyveromyces marxianus with either Lactobacillus plantarum or Pediococcus pentosaceus on the physiochemical and nutritional properties of white kidney bean flour sourdough was investigated. The results indicated that mixed-strain fermentation reduced the anti-nutritional factors produced from the white kidney bean flour, especially in the sourdough fermented by L. plantarum and K. marxianus (WKS-LK) compared to that by P. pentosaceus and K. marxianus (WKS-JK). Meanwhile, the content of lactic acid and acetic acid and the proportion of peptides with molecular weights ranging from <500 to 5000 Da were increased in the sourdoughs (WKS-LK > WKS-JK). Compared to the control (WK), microstructural characteristics of the dough seemed to be improved in WKS-LK followed by WKS-JK in terms of their corresponding gluten network consistency. Moreover, mixed fermentation led to a reduced starch digestibility accompanied by a higher content of resistant starch and slowly digestible starch. In contrast, protein digestibility was enhanced in WKS-LK and WKS-JK sourdough breads. More importantly, the changes in gut microbiota composition, short-chain fatty acid (SCFA) production, systemic inflammation, glucose tolerance and liver tissue histopathology following 21-day consumption of the sourdough bread were also evaluated via an animal model. The intake of sourdough breads reduced the abundance of the pathogenic microbiota Escherichia shigella. In contrast, the corresponding abundance of Rikenellaceae, Akkermansiaceae, Erysipelotrichaceae, Prevotellaceae and Eubacterium coprostanoligenes was increased, followed by enhanced SCFA generation, with the highest in WKS-LK and then WKS-JK. Meanwhile, a reduced level of pro-inflammatory cytokines IL-1ß, IL-6 and TNF-α in the serum and improved glucose tolerance and liver tissue histopathology following the bread consumption were also achieved in the order of WKS-LK, then WKS-JK mice compared to WK.


Assuntos
Microbioma Gastrointestinal , Phaseolus , Animais , Camundongos , Fermentação , Pão/análise , Amido , Glucose , Farinha/análise
20.
Antioxidants (Basel) ; 11(4)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35453332

RESUMO

The interaction of protein carrier and polyphenol is variable due to their environmental sensitivity. In this study, the interaction between resveratrol and whey protein isolate (WPI), sodium caseinate (SC) and soy protein isolate (SPI) during storage were systematically investigated from the aspects of polyphenol loading, antioxidant activity and oxidability. It was revealed that resveratrol loaded more in the SPI core and existed both in the core of SC micelles and on the particle surface, while WPI and resveratrol mainly formed in complexes. The loading capacity of the three proteins ranked in order SC > SPI > WPI. ABTS assay showed that the antioxidant activity of the protein carriers in the initial state was SC > SPI > WPI. The results of sulfhydryl, carbonyl and amino acid analysis showed that protein oxidability was SPI > SC > WPI. WPI, with the least oxidation, improved the storage stability of resveratrol, and the impact of SC on resveratrol stability changed from a protective to a pro-degradation effect. Co-oxidation occurred between SPI and resveratrol during storage, which refers to covalent interactions. The data gathered here suggested that the transition between the antioxidant and pro-oxidative properties of the carrier is the primary factor to investigate its protective effect on the delivered polyphenol.

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