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1.
Environ Pollut ; 292(Pt A): 118306, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34634401

RESUMO

Slaughter wastewater is an important and wide range of environmental issues, and even threaten human health through meat production. A high efficiency and stability microsphere-immobilized Bacillus velezensis strain was designed to remove organic matter and inhibit the growth of harmful bacteria in process of slaughter wastewater. Bacillus velezensis was immobilized on the surface of sodium alginate (SA)/Polyvinyl alcohol (PVA)/Nano Zinc Oxide (Nano-ZnO) microsphere with the adhesion to bio-carrier through direct physical adsorption. Results indicated that SA/PVA/ZnO and SA/ZnO microspheres could inhibit E.coli growth with adding 0.15 g/L nano-ZnO and not affect Bacillus velezensis strain, and the removal the chemical oxygen demand (COD) rates of SA/PVA/ZnO microsphere immobilized cells are 16.99%, followed by SA/ZnO (13.69%) and free bacteria (7.61%) from 50% concentration slaughter wastewater within 24 h at 37 °C, pH 7.0, and 120 rpm, a significant difference was found between the microsphere and control group. Moreover, when the processing time reaches 36 h, COD degradation of SA/PVA/ZnO microsphere is obviously higher than other groups (SA/PVA/ZnO:SA/ZnO:control vs 18.535 : 15.446: 10.812). Similar results were obtained from 30% concentration slaughter wastewater. Moreover, protein degradation assay was detected, and there are no significant difference (SA/PVA/ZnO:SA/ZnO:control vs 35.4 : 34.4: 36.0). The design of this strategy could greatly enhance the degradation efficiency, inhibit the growth of other bacteria and no effect on the activity of protease in slaughter wastewater. These findings suggested that the nano-ZnO hydrogel immobilization Bacillus velezensis system wastewater treatment is a valuable alternative method for the remediation of pollutants from slaughter wastewater with a novel and eco-friendly with low-cost investment as an advantage.


Assuntos
Óxido de Zinco , Bacillus , Humanos , Microesferas , Álcool de Polivinil , Águas Residuárias
2.
Food Chem ; 370: 130901, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34500289

RESUMO

The development of Aspergillus niger (A. niger) spores as glucose oxidase (GOD) biocatalysts to produce gluconic acid is highly anticipated in the food industry. Herein, a piezoelectric sensor (PIS) method has been developed for the detection of GOD activity and better application of rapid screening of GOD activity in A. niger spores. The GOD activity detection is based on GOD catalyzing ß-d-glucose to produce gluconic acid, which results in frequency shift changes recorded by the PIS device in real-time. Using the PIS method, the kinetic parameter 6.5 mg/mL, the correlation equation υ0=31.92CGOD+1.04, the recoveries (89.4%-93.9%, and their RSDs were all within 6.1%) and the optimal GOD activity in A. niger spores under different treatment conditions was obtained. Compared with the classical methods, the proposed method is accurate, rapid, convenient and does not require additional reagents. It has a broad range of potential applications for exploring new GOD biocatalysts.


Assuntos
Aspergillus niger , Glucose Oxidase , Glucose , Esporos Fúngicos
3.
Food Funct ; 12(20): 9549-9562, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34664582

RESUMO

As non-coding RNA molecules, microRNAs (miRNAs) are widely known for their critical role in gene regulation. Recent studies have shown that plant miRNAs obtained through dietary oral administration can survive in the gastrointestinal (GI) tract, enter the circulatory system and regulate endogenous mRNAs. Diet-derived plant miRNAs have 2'-O-methylated modified 3'ends and high cytosine and guanine (GC) content, as well as exosomal packaging, which gives them high stability even in the harsh environment of the digestive system and circulatory system. The latest evidence shows that dietary plant miRNAs can not only be absorbed in the intestine, but also be absorbed and packaged by gastric epithelial cells and then secreted into the circulatory system. Alternatively, these biologically active plant-derived miRNAs may also affect the health of the host by affecting the function of the microbiome, while not need to be taken into the host's circulatory system and transferred to remote tissues. This cross-kingdom regulation of miRNAs gives us hope for exploring their therapeutic potential and as dietary supplements. However, doubts have also been raised about the cross-border regulation of miRNAs, suggesting that technical flaws in the experiments may have led to this hypothesis. In this article, we summarize the visibility of dietary plant miRNAs in the development of human health and recent research data on their use in therapeutics. The regulation of plant miRNAs across kingdoms is a novel concept. Continued efforts in this area will broaden our understanding of the biological role of plant miRNAs and will open the way for the development of new approaches to prevent or treat human diseases.

4.
Crit Rev Food Sci Nutr ; : 1-15, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34132617

RESUMO

Monascus pigments are a kind of high-quality natural edible pigments fermented by Monascus filamentous fungi, which have been widely used in food, cosmetics, medicine, textiles, dyes and chemical industries as active functional ingredients. Moreover, Monascus pigments have a good application prospect because of a variety of biological functions such as antibacterial, antioxidation, anti-inflammatory, regulating cholesterol, and anti-cancer. However, the low productivity and color value of pigments restrict their development and application. In this review, we introduced the categories, structures, biosynthesis and functions of Monascus pigments, and summarized the current methods for improving the productivity and color value of pigments, including screening and mutagenesis of strains, optimization of fermentation conditions, immobilized fermentation, mixed fermentation, additives, gene knockout and overexpression technologies, which will help to develop the foundation for the industrial production of Monascus pigments.

5.
Food Chem ; 336: 127669, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32758804

RESUMO

Curcumin was recently attracted great interest owing to its multiple bioactivities; however, the use of curcumin was hindered by its poor solubility and stability. In this study, curcumin-nisin-soy soluble polysaccharide nanoparticles (Cur-Nisin-SSPS-NPs, size = 118.76 nm) have been successfully elaborated to improve the application of curcumin. The formation of Cur-Nisin-SSPS-NPs was mediated by amphiphilic and positively charged nisin: SSPS encapsulated nisin, which was mainly driven by electrostatic attraction. And nisin-SSPS complex encapsulated curcumin mainly through hydrophobic interactions between nisin and curcumin. The encapsulation efficiency of curcumin (91.66%) in this novel nanocarriers was significantly higher than that in nanoparticles prepared by a single SSPS (31.82%) or nisin (41.69%), most likely because more hydrophobic regions of nisin were exposed after interacting with SSPS through electrostatic interaction. Consequently, this facile and green nanocarriers improved the solubility/dispersibility and stability of curcumin and nisin, as well as endowed SSPS-based nanoparticles with antioxidant and antimicrobial activities.


Assuntos
Curcumina/administração & dosagem , Portadores de Fármacos/química , Nanopartículas/química , Nisina/química , Polissacarídeos/química , Antibacterianos/administração & dosagem , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Curcumina/química , Curcumina/farmacocinética , Liberação Controlada de Fármacos , Interações Hidrofóbicas e Hidrofílicas , Imidazóis , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Morfolinas , Solubilidade , Soja/química , Espectrofotometria Ultravioleta
7.
J Agric Food Chem ; 68(24): 6672-6682, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32489101

RESUMO

To achieve the accumulation of targeted secondary metabolites, microorganisms must adopt various protection mechanisms to avoid or reduce damage to cells caused by abiotic stresses, which formed from the changes of physical and chemical culture conditions. The protection mechanism of Monascus sp. to tolerate high-concentration ammonium chloride was analyzed by sequential window acquisition of all theoretical mass spectra-mass spectrometry proteomics in this work, and the results indicated that abiotic stresses caused by high-concentration ammonium chloride inhibited the synthesis of chitin and glycoprotein, leading to a decrease in cell wall integrity and, thus, affecting cell growth. At the same time, it also inhibited the complex enzyme III and IV activities of the mitochondrial cytochrome respiratory chain, leading to an increase in reactive oxygen species (ROS) levels. With the aim to respond to abiotic stresses, the cross-protection mechanism was implemented in Monascus, including self-protection of the Monascus cell by promoting synthesis of trehalose, a molecular chaperone that facilitates protein folding (such as heat-shock protein) and autophagy-related proteins, through not the enzyme protection system (superoxide dismutase, peroxidase, catalase, NADPH oxidase, and alternative oxidase) but the glutathione/glutaredoxin system, to maintain the intracellular redox state and then eliminate or reduce ROS damage to the cell. At the same time, an alternative respiratory pathway related to NADH dehydrogenase was activated to balance the material and energy metabolism.


Assuntos
Cloreto de Amônio/farmacologia , Proteínas Fúngicas/metabolismo , Monascus/efeitos dos fármacos , Monascus/genética , Catalase/genética , Catalase/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Espectrometria de Massas , Monascus/química , Monascus/metabolismo , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Proteômica , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
8.
Bone Res ; 6: 28, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30210900

RESUMO

Signal transduction between different organs is crucial in the normal development of the human body. As an important medium for signal communication, exosomes can transfer important information, such as microRNAs (miRNAs), from donors to receptors. MiRNAs are known to fine-tune a variety of biological processes, including maxillofacial development; however, the underlying mechanism remains largely unknown. In the present study, transient apoptosis was found to be due to the expression of a miniature swine maxillofacial-specific miRNA, ssc-mir-133b. Upregulation of ssc-mir-133b resulted in robust apoptosis in primary dental mesenchymal cells in the maxillofacial region. Cell leukemia myeloid 1 (Mcl-1) was verified as the functional target, which triggered further downstream activation of endogenous mitochondria-related apoptotic processes during tooth development. More importantly, mandible exosomes were responsible for the initial apoptosis signal. An animal study demonstrated that ectopic expression of ssc-mir-133b resulted in failed tooth formation after 12 weeks of subcutaneous transplantation in nude mice. The tooth germ developed abnormally without the indispensable exosomal signals from the mandible.

9.
Stem Cell Res Ther ; 8(1): 198, 2017 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-28962585

RESUMO

BACKGROUND: Traumatic brain injury (TBI) is one of the major causes of mortality and disability for all ages worldwide. Mesenchymal stem cells (MSCs)-originated exosomes have provided therapeutic effects. However, as an indispensable component of MSCs, whether odontogenic stem cell-generated exosomes could benefit TBI is still unclear. Thus we aimed to explore the potential of stem cells from human exfoliated deciduous teeth-originated exosomes (SHED-Ex) for the management of TBI. METHODS: First, a transwell system was used to co-culture activated BV-2 microglia cells with SHED. The secretion levels of neuroinflammatory factors and nitrite were evaluated by enzyme-linked immunosorbent assay (ELISA) and Griess assay. Furthermore, purified SHED-Ex were co-cultured with activated BV-2. ELISA, Griess assay, flow cytometry, immunofluorescence, and qRT-PCR were performed to test the levels of inflammatory factors as well as the microglia phenotype. Finally, SHED and SHED-Ex were locally injected into TBI rat models. Basso, Beattie, and Bresnahan (BBB) scores were chosen to evaluate the motor functional recovery. Histopathology and immunofluorescence were performed to measure the lesion volume and neuroinflammation. RESULTS: As a result, SHED-Ex could reduce neuroinflammation by shifting microglia polarization. The administration of SHED-Ex improves rat motor functional recovery and reduces cortical lesion compared with the control group 2 weeks post-injury (P < 0.05). CONCLUSIONS: The current study demonstrates for the first time that SHED-Ex contribute a therapeutic benefit to TBI in rats, at least in part by shifting microglia polarization to reduce neuroinflammation. The use of odontogenic stem cells, and indeed their exosomes, may be expanded for the treatment of TBI or other neurological disorders.


Assuntos
Lesões Encefálicas Traumáticas/terapia , Diferenciação Celular , Exossomos/transplante , Células-Tronco Mesenquimais/metabolismo , Microglia/citologia , Animais , Linhagem Celular , Exossomos/metabolismo , Humanos , Masculino , Microglia/metabolismo , Ratos , Ratos Wistar , Dente Decíduo/citologia
10.
Biosens Bioelectron ; 43: 115-9, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23291614

RESUMO

Emergence of drug-resistance tuberculosis (DR-TB) represents a serious threat to the world. Most countries, especially the developing countries, lack efficacious and inexpensive tools for early detection of Mycobacterium tuberculosis (M. tuberculosis) resistance to antituberculosis drugs and for preventing the carriers from acquiring further resistance. This report describes an indirect series piezoelectric (ISP) system for simultaneous and early detection of M. tuberculosis resistance to antituberculosis drugs. The ISP system can continually monitor the frequency shift change profiles of 32 detection cells resulting from the changes of volatile metabolites group during M. tuberculosis growth. The quantification detection time (QDT) obtained from the frequency shift change profile was found to be characterisitc of M. tuberculosis resistance. A drug-free chamber was used as a control, in which 1% of M. tuberculosis isolate was added. By comparing the QDT obtained from growth of M. tuberculosis isolate in each drug-containing chamber with that in a drug-free chamber, forty strains of clinical M. tuberculosis isolates were categorized by our method. Comparison was also made using the agar proportion method (APM) and the BACTEC™ MGIT™ 960 system. The mean time for interpretive category of M. tuberculosis resistance measured by the ISP system is (111.7 ± 28.45)h, which is more rapid than by the APM [(600.0 ± 50.30)h] and the BACTEC™ MGIT™ 960 system [(140.3 ± 39.52)h]. The present system is accurate, rapid and cost-effective with a wide application in early detection of DR-TB in the developing countries.


Assuntos
Antituberculosos/uso terapêutico , Técnicas Biossensoriais/instrumentação , Análise de Injeção de Fluxo/instrumentação , Sistemas Microeletromecânicos/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/fisiologia , Proliferação de Células/efeitos dos fármacos , Farmacorresistência Bacteriana , Desenho de Equipamento , Análise de Falha de Equipamento
11.
Biosens Bioelectron ; 24(3): 403-9, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18539020

RESUMO

Many of the deaths caused by tuberculosis (TB) in the world are due to wrong or late diagnosis. The World Health Organization (WHO) calls for better and cheaper TB tests method for this reason. In this paper, a new multi-channel series piezoelectric quartz crystal (MSPQC) sensor system was developed for rapid growth and detection of Mycobacterium tuberculosis. It is an automatic continuous monitoring system. The system was used to detect TB based on the volatile metabolic products NH(3) and CO(2) during the growth of M. tuberculosis. The metabolic products, diffusing from the medium into the KOH absorbing solution, resulted in the conductance change of the absorbing solution detected by the MSPQC sensitively. The frequency shift versus time response curves were recorded by self-developed software. Frequency detection time (FDT) corresponding to -100 Hz in frequency shift value was used as a parameter to quantitatively determine M. tuberculosis H37Ra (an avirulent strain). H37Ra and 40 strains clinic positive samples were detected by the proposed system successfully. As for H37Ra, the FDT had a linear relationship with the logarithm of its initial concentration in the range of 10(2)-10(7) colony forming units (cfu)ml(-1) (R=-0.998) and the detection limit was low to 10 cfu ml(-1). 4% NaOH solution that can kill contaminating microorganisms and make M. tuberculosis alive was used as pretreatment reagent to provide selectivity to this method. Comparative tests were also carried out by using BACTEC MGIT 960 and conventional Lowenstein-Jensen (L-J) slants. The results showed that the proposed system was quicker than BACTEC MGIT 960 and it is also cheaper and will be widely used in TB tests in the world.


Assuntos
Técnicas Bacteriológicas/métodos , Mycobacterium tuberculosis/isolamento & purificação , Amônia/metabolismo , Dióxido de Carbono/metabolismo , Meios de Cultura , Descontaminação , Humanos , Hidróxidos/química , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/metabolismo , Compostos de Potássio/química , Quartzo/química , Hidróxido de Sódio/farmacologia
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