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1.
Food Chem ; 305: 125447, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31499289

RESUMO

A novel α-amylase gene (RmAmyA) from Rhizomucor miehei was cloned and expressed in Pichia pastoris. RmAmyA showed 70% amino acid identity with the α-amylase from Rhizomucor pusillus. A high α-amylase activity of 29,794.2 U/mL was found through high cell density fermentation. The molecular mass of RmAmyA was determined to be 49.9 kDa via SDS-PAGE. RmAmyA was optimally active at 75 °C and pH 6.0, and it did not require Ca2+ to improve its activity. It exhibited broad substrate specificity towards amylose, amylopectin, soluble starch, pullulan, and cyclodextrins. High level of maltose (54%, w/w) was produced after liquefied starch was hydrolysed with RmAmyA for 16 h. Moreover, the addition of RmAmyA into Chinese steamed bread resulted in 7.7% increment in the specific volume, and 17.2% and 11.5% reduction in the chewiness and hardness, respectively. These results indicate that RmAmyA might be a potential candidate for applications in the food industry.

2.
Food Chem ; 309: 125709, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31708343

RESUMO

To produce manno-oligosaccharides from cassia gum, a mutated glycoside hydrolase family 134 ß-mannanase gene (mRmMan134A) from Rhizopus microsporus var. rhizopodiformis F518 was expressed in Pichia pastoris and a high expression level (3680 U mL-1) was obtained through high cell density fermentation. mRmMan134A exhibited maximum activity at pH 5.5 and 50 °C. It was then subjected to hydrolyze cassia gum with 70.6% of overall yield of manno-oligosaccharides. From the hydrolysate, seven components (F1-F7) were separated and identified as mannose, mannobiose, galactose, mannotriose, mannotetraose, 61-α-d-galactosyl-ß-d-mannobiose, and mannopentaose, respectively. According to in vitro fermentation, the manno-oligosaccharides were able to promote the growth of three Bifidobacterium strains and six Lactobaillus strains with 3.0-fold increment in culture absorbance, and these strains preferred manno-oligosaccharides with degree of polymerization (DP) 2-3 rather than those with DP 4-5. Novel manno-oligosaccharides from cassia gum with promising prebiotic activity were provided in the present study.

3.
J Rehabil Med ; 51(9): 692-697, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31418043

RESUMO

OBJECTIVE: To provide detailed data on the effects of multidisciplinary rehabilitation for patients with neuromyelitis optica spectrum disorder with moderate to severe disability. DESIGN: A pilot randomized control study. SUBJECTS/PATIENTS: A total of 39 patients with neuromyelitis optica spectrum disorder were randomized into intervention or control groups. METHODS: The intervention group received multidisciplinary rehabilitation 5 times/week for 4 weeks in a hospital, and the patients were guided to continue community- or home-based rehabilitation for 3 months. The control group did not receive any specific rehabilitation intervention. Disability was assessed using the Extended Disability Status Scale (EDSS) and Functional Systems (FS) scores after 4 weeks of rehabilitation and 3 months of follow-up. RESULTS: The mean EDSS score was 7.5 at admission for both groups. Improvements (p<0.05) in the EDSS score and domains of bowel, bladder and motor functions (pyramidal and walking function) were noted in the multidisciplinary rehabilitation group after 4 weeks. After 3 months, the patients in the usual care group showed improvement in EDSS score and walking ability score; however, no significant changes in other variables were noted. CONCLUSION: These results suggest that multidisciplinary rehabilitation potentially promotes motor functional recovery in patients with neuromyelitis optica spectrum disorders.


Assuntos
Neuromielite Óptica/reabilitação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
4.
Dalton Trans ; 46(9): 2829-2843, 2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-28177011

RESUMO

A new CNNC carbene-phthalazine tetradentate ligand has been synthesised, which in the reaction with [Ru(T)Cl3] (T = trpy, tpm, bpea; trpy = 2,2';6',2''-terpyridine; tpm = tris(pyrazol-1-yl)methane; bpea = N,N-bis(pyridin-2-ylmethyl)ethanamine) in MeOH or iPrOH undergoes a C-N bond scission due to the nucleophilic attack of a solvent molecule, with the subsequent formation of the mononuclear complexes cis-[Ru(PhthaPz-OR)(trpy)X]n+, [Ru(PhthaPz-OMe)(tpm)X]n+ and trans,fac-[Ru(PhthaPz-OMe)(bpea)X]n+ (X = Cl, n = 1; X = H2O, n = 2; PhthaPz-OR = 1-(4-alkoxyphthalazin-1-yl)-3-methyl-1H-imidazol-3-ium), named 1a+/2a2+ (R = Me), 1b+/2b2+ (R = iPr), 3+/42+ and 5+/62+, respectively. Interestingly, regulation of the stability regions of different Ru oxidation states is obtained by different ligand combinations, going from 62+, where Ru(iii) is clearly stable and mono-electronic transfers are favoured, to 2a2+/2b2+, where Ru(iii) is almost unstable with regard to its disproportionation. The catalytic performance of the Ru-OH2 complexes in chemical water oxidation at pH 1.0 points to poor stability (ligand oxidation), with subsequent evolution of CO2 together with O2, especially for 42+ and 62+. In electrochemically driven water oxidation, the highest TOF values are obtained for 2a2+ at pH 1.0. In alkene epoxidation, complexes favouring bi-electronic transfer processes show better performances and selectivities than those favouring mono-electronic transfers, while alkenes containing electron-donor groups show better performances than those bearing electron-withdrawing groups. Finally, when cis-ß-methylstyrene is employed as the substrate, no cis/trans isomerization takes place, thus indicating the existence of a stereospecific process.

5.
J Agric Food Chem ; 60(38): 9770-8, 2012 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-22950859

RESUMO

In this study with aflatoxin-contaminated peanuts, the effectiveness of electrolyzed oxidizing water (EOW) in the decontamination of aflatoxin B(1) was investigated. The aflatoxin B(1) content was markedly reduced upon treatment with EOW, particularly with neutral electrolyzed oxidizing water (NEW). The conversion product of EOW treatment was isolated and identified as 8-chloro-9-hydroxy aflatoxin B(1) (compound 1), which is an amphiphilic molecule, in contrast to fat-soluble aflatoxin B(1). A mutagenic response study revealed that the number of revertants per plate after treatment of bacterial strains TA-97, TA-98, TA-100, and TA-102 with NEW was within the standard value range. The HepG2 cell viability assay yielded an IC(50) value of compound 1 approximately 150 mM. This study indicates that EOW had the ability to decontaminate aflatoxin B(1), and the conversion product, compound 1, did not exhibit mutagenic activity or cytotoxic effects.


Assuntos
Aflatoxina B1/química , Arachis/química , Descontaminação , Eletrólise/métodos , Contaminação de Alimentos , Inocuidade dos Alimentos/métodos , Aflatoxina B1/análise , Aflatoxinas/química , Aflatoxinas/toxicidade , Arachis/microbiologia , Aspergillus flavus/patogenicidade , Cromatografia Líquida de Alta Pressão , Células Hep G2 , Humanos , Estrutura Molecular , Testes de Mutagenicidade/métodos , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética
6.
Int J Food Microbiol ; 137(1): 67-75, 2010 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-19926156

RESUMO

Neutralized electrolyzed oxidizing water (NEW) and acidic electrolyzed oxidizing water (AcEW) are electrolyzed oxidizing waters (EOW) that have significantly different fungicidal efficiencies against Aspergillus flavus (A. flavus) (The actuation durations of no survival population to NEW and AcEW were 90s and 120s, respectively.), even when used at the same available chlorine concentration (30ppm). It has been verified by our previous research. This study hypothesized that this difference did not originate from the structure of water but based on the OH radical (OH). It was proved by the UV spectroscopy, (17)O-NMR spectroscopy and electron spin resonance analysis. NEW contains more OH compared with AcEW in the same available chlorine concentration level. The OH that exists in NEW and AcEW was found to have an important fungicidal factor that destroys the cellular structures of the A. flavus conidia. It also damages the cellular normal function of A. flavus conidia that brought about K+ and Mg2+ leakages. The levels of OH that exist in NEW and AcEW could be the important reason that leads to significant fungicidal efficiencies against A. flavus.


Assuntos
Aspergillus flavus/efeitos dos fármacos , Microbiologia de Alimentos , Peróxido de Hidrogênio/farmacologia , Aspergillus flavus/metabolismo , Aspergillus flavus/patogenicidade , Aspergillus flavus/ultraestrutura , Permeabilidade da Membrana Celular/efeitos dos fármacos , Fenômenos Químicos , Desinfetantes/farmacologia , Combinação de Medicamentos , Espectroscopia de Ressonância de Spin Eletrônica , Contaminação de Alimentos/prevenção & controle , Depuradores de Radicais Livres/farmacologia , Humanos , Magnésio/metabolismo , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Micotoxinas/biossíntese , Micotoxinas/toxicidade , Óleos , Fenóis , Potássio/metabolismo , Espectrofotometria Ultravioleta , Superóxidos/farmacologia
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