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1.
Int J Mol Sci ; 25(12)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38928460

RESUMO

Osteoporosis, a prevalent chronic health issue among the elderly, is a global bone metabolic disease. Flavonoids, natural active compounds widely present in vegetables, fruits, beans, and cereals, have been reported for their anti-osteoporotic properties. Onion is a commonly consumed vegetable rich in flavonoids with diverse pharmacological activities. In this study, the trabecular structure was enhanced and bone mineral density (BMD) exhibited a twofold increase following oral administration of onion flavonoid extract (OFE). The levels of estradiol (E2), calcium (Ca), and phosphorus (P) in serum were significantly increased in ovariectomized (OVX) rats, with effects equal to alendronate sodium (ALN). Alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) levels in rat serum were reduced by 35.7% and 36.9%, respectively, compared to the OVX group. In addition, the effects of OFE on bone health were assessed using human osteoblast-like cells MG-63 and osteoclast precursor RAW 264.7 cells in vitro as well. Proliferation and mineralization of MG-63 cells were promoted by OFE treatment, along with increased ALP activity and mRNA expression of osteoprotegerin (OPG)/receptor activator of nuclear factor-kappaB ligand (RANKL). Additionally, RANKL-induced osteoclastogenesis and osteoclast activity were inhibited by OFE treatment through decreased TRAP activity and down-regulation of mRNA expression-related enzymes in RAW 264.7 cells. Overall findings suggest that OFE holds promise as a natural functional component for alleviating osteoporosis.


Assuntos
Diferenciação Celular , Proliferação de Células , Flavonoides , Cebolas , Osteoblastos , Osteogênese , Osteoporose , Extratos Vegetais , Ligante RANK , Animais , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Ligante RANK/metabolismo , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo , Osteoporose/patologia , Flavonoides/farmacologia , Camundongos , Cebolas/química , Diferenciação Celular/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Ratos , Proliferação de Células/efeitos dos fármacos , Células RAW 264.7 , Osteogênese/efeitos dos fármacos , Humanos , Feminino , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Densidade Óssea/efeitos dos fármacos , Ovariectomia , Ratos Sprague-Dawley , Osteoprotegerina/metabolismo , Osteoprotegerina/genética
2.
Molecules ; 29(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38792167

RESUMO

Methylglyoxal-induced ROS elevation is the primary cause of neuronal damage. Metformin is a traditional hypoglycemic drug that has been reported to be beneficial to the nervous system. In this study, flavonoids were found to enhance the protective effect of metformin when added at a molar concentration of 0.5%. The structure-activity relationship (SAR) analysis indicated that ortho- substitution in the B ring, and the absence of double bonds between the 2 and 3 position combined with the gallate substitution with R configuration at the 3 position in the C ring played crucial roles in the synergistic effects, which could be beneficial for designing a combination of the compounds. Additionally, the mechanism study revealed that a typical flavonoid, EGCG, enhanced ROS scavenging and anti-apoptotic ability via the BCL2/Bax/Cyto C/Caspase-3 pathway, and synergistically inhibited the expression of GSK-3ß, BACE-1, and APP in PC-12 cells when used in combination with metformin. The dose of metformin used in the combination was only 1/4 of the conventional dose when used alone. These results suggested that ROS-mediated apoptosis and the pathways related to amyloid plaques (Aß) formation can be the targets for the synergistic neuroprotective effects of flavonoids and metformin.


Assuntos
Apoptose , Sinergismo Farmacológico , Flavonoides , Metformina , Aldeído Pirúvico , Espécies Reativas de Oxigênio , Metformina/farmacologia , Metformina/química , Ratos , Flavonoides/farmacologia , Flavonoides/química , Células PC12 , Animais , Relação Estrutura-Atividade , Apoptose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Neuroblastoma/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Transdução de Sinais/efeitos dos fármacos
3.
Nanoscale ; 15(24): 10412-10422, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37305976

RESUMO

Aligned carbon nanotube (CNT) arrays have been widely used in the preparation of polymer composites. CNT arrays are commonly prepared by chemical vapor deposition (CVD) in a high temperature tubular furnace, and the areas of the aligned CNT/polymer membranes prepared are relatively small (<30 cm2) due to the limitation of the inner diameter of the furnace, which limits its practical application in the field of membrane separation. Herein, the vertically aligned CNT arrays/polydimethylsiloxane (PDMS) membrane with large and expandable area was prepared by a modular splicing method for the first time, with a maximum area of 144 cm2. The addition of CNT arrays with openings at both ends significantly improved the pervaporation performance of the PDMS membrane for ethanol recovery. At 80 °C, the flux (671.6 g m-2 h-1) and separation factor (9.0) of CNT arrays/PDMS membrane were increased by 435.12% and 58.52%, respectively, compared with those of the PDMS membrane. Furthermore, the expandable area enabled the CNT arrays/PDMS membrane to couple with fed-batch fermentation for pervaporation for the first time, which increased the ethanol yield (0.47 g g-1) and productivity (2.34 g L-1 h-1) by 9.3% and 4.9% respectively compared with batch fermentation. Besides, the flux (135.47-166.79 g m-2 h-1) and separation factor (8.83-9.21) of CNT arrays/PDMS membrane remained stable in this process, indicating that this membrane has the potential to be applied in industrial bioethanol production. This work provides a new idea for the preparation of large-area aligned CNT/polymer membranes, and also opens up a new direction for the application of large-area aligned CNT/polymer membranes.


Assuntos
Nanotubos de Carbono , Etanol , Fermentação , Membranas Artificiais , Dimetilpolisiloxanos , Polímeros
4.
Eng Life Sci ; 23(6): e2200125, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37275213

RESUMO

Traditional technology of cell disruption has become one of the bottlenecks restricting the industrialization of genetic engineering products due to its high cost and low efficiency. In this study, a novel bioprocess of phage lysis coupled with salting-out extraction (SOE) was evaluated. The lysis effect of T7 phage on genetically engineered Escherichia coli expressing κ-carrageenase was investigated at different multiplicity of infection (MOI), meanwhile the phage and enzyme released into the lysate were separated by SOE. It was found that T7 phage could lyse 99.9% of host cells at MOI = 1 and release more than 90.0% of enzyme within 90 min. After phage lysis, 87.1% of T7 phage and 71.2% of κ-carrageenase could be distributed at the middle phase and the bottom phase, respectively, in the SOE system composed of 16% ammonium sulfate and 20% ethyl acetate (w/w). Furthermore, κ-carrageenase in the bottom phase could be salted out by ammonium sulfate with a yield of 40.1%. Phage lysis exhibits some advantages, such as mild operation conditions and low cost. While SOE can efficiently separate phage and intracellular products. Therefore, phage lysis coupled with SOE is expected to become a viable alternative to the classical cell disruption and intracellular product recovery.

6.
Foods ; 12(6)2023 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-36981234

RESUMO

Milk thistle is a traditional medicinal herb. Silybin is a medicinal component found in the seed coat of milk thistle, which has liver-protective and anti-cancer properties. Conventional studies have focused on the extraction of silybin with organic reagents, which was inapplicable to the food industry. This study aims to develop a fermented milk containing silybin and protein from the milk thistle seeds. A three step procedure was developed, comprising homogenization of milk thistle seeds, NaHCO3 heat treatment, and microbial fermentation. The silybin was characterized by high performance liquid chromatography, and the protein was quantified and electrophorized. It was found that the homogenization step was essential for the preparation of protein, and the NaHCO3 heat treatment was the crucial step in obtaining silybin. The optimal NaHCO3 treatment settings were 1% NaHCO3, 60°C, and 3 h, and the optimal strains for microbial fermentation were L131 (Rummeliibacillus stabekisii) and RS72 (Lactobacillus plantarum). The silybin yield in the fermented milk reached 11.24-12.14 mg/g seeds, accounting for 72.6-78.4% of the total silybin in the milk thistle seeds, and the protein yield reached 121.8-129.6 mg/g seeds. The fermented milk had a slightly sweet yoghurt-like flavor and could be used as a dietary supplement for silybin and protein.

7.
Food Chem ; 412: 135581, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-36731239

RESUMO

Nelumbo nucifera Gaertn, commonly known as lotus, is a genus comprising perennial and rhizomatous aquatic plants, found throughout Asia and Australia. This review aimed to cover the biosynthesis of flavonoids, alkaloids, and lipids in plants and their types in different parts of lotus. This review also examined the physiological functions of bioactive compounds in lotus and the extracts from different organs of the lotus plant. The structures and identities of flavonoids, alkaloids, and lipids in different parts of lotus as well as their biosynthesis were illustrated and updated. In the traditional medicine systems and previous scientific studies, bioactive compounds and the extracts of lotus have been applied for treating inflammation, cancer, liver disease, Alzheimer's disease, etc. We suggest future studies to be focused on standardization of the extract of lotus, and their pharmacological mechanisms as drugs or functional foods. This review is important for the lotus-based food processing and application.


Assuntos
Alcaloides , Lotus , Nelumbo , Nelumbo/química , Alcaloides/química , Extratos Vegetais/química , Flavonoides , Lipídeos
8.
Molecules ; 28(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36838890

RESUMO

Although black soldier fly larvae (BSFL) can convert food waste into insectile fatty acids (FAs), the chronological and diet-dependent transformation of larval FAs has yet to be determined. This study focused on the dynamics of larval FA profiles following food waste treatment and characterized factors that may drive FA composition and bioaccumulation. Larval FA matters peaked on Day 11 as 7.7 ± 0.7% of food waste dry matter, maintained stably from Day 11-19, and decreased slightly from Day 19-21. The BSFL primarily utilized waste carbohydrates for FA bioconversion (Day 0-11) and shifted to waste FAs (Day 7-17) when the carbohydrates were close to depletion. The optimal time window for larvae harvest was Days 17-19, which fulfilled both targets of waste oil removal and larval FA transformation. Larval FAs were dominated by C12:0, followed by C18:2, C18:1, and C16:0. The waste-reducing carbohydrate primarily accounted for larval FA bioaccumulation (r = -0.947, p < 0.001). The increase in diet carbohydrate ratio resulted in the elevation of larval C12:0 yield, which indicated that larval C12:0-FA was primarily biosynthesized from carbohydrates and further transformed from ≥C16 FAs. This study elucidates the bioaccumulation process of larval FAs for food waste treatment and highlights the importance of waste carbohydrates for both the composition and transformation of larval FAs.


Assuntos
Dípteros , Eliminação de Resíduos , Animais , Larva , Alimentos , Ácidos Graxos , Carboidratos
9.
Molecules ; 27(22)2022 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-36431904

RESUMO

Methylglyoxal-induced oxidative stress and cytotoxicity are the main factors causing neuronal death-related, diabetically induced memory impairment. Antioxidant and anti-apoptotic therapy are potential intervention strategies. In this study, 25 flavonoids with different substructures were assayed for protecting PC-12 cells from methylglyoxal-induced damage. A structure-activity relationship (SAR) analysis indicated that the absence of the double bond at C-2 and C-3, substitutions of the gallate group at the 3 position, the pyrogallol group at the B-ring, and the R configuration of the 3 position enhanced the protection of flavan-3-ols, and a hydroxyl substitution at the 4' and meta-positions were important for the protection of flavonol. These SARs were further confirmed by molecular docking using the active site of the Keap1-Nrf2 complex as the receptor. The mechanistic study demonstrated that EGCG with the lowest EC50 protected the PC-12 cells from methylglyoxal-induced damage by reducing oxidative stress via the Nrf2/Keap1/HO-1 and Bcl-2/Bax signaling pathways. These results suggested that flavan-3-ols might be a potential dietary supplement for protection against diabetic encephalopathy.


Assuntos
Fator 2 Relacionado a NF-E2 , Neuroblastoma , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Aldeído Pirúvico/toxicidade , Flavonoides/farmacologia , Simulação de Acoplamento Molecular , Estresse Oxidativo , Relação Estrutura-Atividade
10.
Curr Microbiol ; 79(2): 54, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34982238

RESUMO

Two-component signal system (TCS) is the predominant bacterial sense-and-response machinery. RpfC/RpfG TCS involved in quorum sensing molecule Diffuse Signal Factor (DSF) signal perception and transduction was well studied in many bacteria. However, whether other environmental factors participating in the signal perception and transduction of RpfC/RpfG was still unclear. Here, we showed that RpfC/RpfG could integrate temperature and DSF signal partially controlling the production of the temperature-dependent protease (SmtP) in S. maltophilia FF11, a strain isolated from frozen Antarctic krill, exhibited spoilage potential due to secret more protease at low temperatures involving in protein degradation. qRT-PCR analysis revealed rpf system mediating approximately 60% transcription activity of Clp, a critical transcription factor linking with LotS/LotR, consisting a signal network controlling completely the SmtP production in previous study. Protease production was partially reduced in rpfF (coding DSF synthetase) mutant strains at 15 °C or 25 °C, not be increased through addition DSF or overexpression RpfF in WT at 37 °C, indicating that DSF was effective for protease production only at low temperatures in S. maltophilia. Additionally, biochemical analysis revealed the enzymatic activity of RpfG from strain FF11 cultured at 37 °C or DSF-deficient strains grown at 25 °C was significantly reduced compared to that of RpfG from strain FF11 cultured at 25 °C. These findings outline an interplay mechanism that allows S. maltophilia to integrate quorum sensing and temperature cues controlling protease production, and imply a potential relationship between two distinct systems of RpfC/RpfG and LotS/LotR.


Assuntos
Stenotrophomonas maltophilia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Peptídeo Hidrolases/genética , Transdução de Sinais , Stenotrophomonas maltophilia/metabolismo , Temperatura
11.
Enzyme Microb Technol ; 153: 109957, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34847438

RESUMO

κ-Carrageenan oligosaccharides from κ-carrageenan hydrolysis are important biochemicals with more bioactivity. Enzyme engineering plays a key role in improving κ-carrageenase catalytic efficiency for production of κ-carrageenan oligosaccharides. Effect of metal ions on enzyme activity, especially stability and efficiency, is main factor in catalytic process, but metal ions addition leads to gelation of κ-carrageenan solution. In this study, molecular dynamics simulation was used to explore the interaction between κ-carrageenase CgkPZ and Ca2+, and Ca2+ bonded to D164 and E167 in the catalytic center resulting in the catalytic efficiency increase. Circular dichroism analysis indicated that the secondary structure of κ-carrageenase could change in the presence of Ca2+. Therefore, a novel self-assembly κ-carrageenase-inorganic hybrid nanoflowers CaNF@CgkPZ was synthesized and systematically characterized. The catalytic efficiency (kcat/Km) of CaNF@CgkPZ was 382.1 mL·mg-1·s-1, increased by 292% compared with free κ-carrageenase. Notably, the enzyme activity of CaNF@CgkPZ was not reduced significantly after 19 cycles use, and 70-100% relative activity was still retained when stored at 4-25 â„ƒ for 15 days. This work provides an efficient approach for κ-carrageenase immobilization with good storage stability, reusability and enhanced catalytic efficiency, which is of great significance in practical applications.


Assuntos
Simulação de Dinâmica Molecular , Catálise , Hidrólise
12.
Insects ; 12(6)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072891

RESUMO

Biowaste treatment by black soldier fly larvae (BSFL, Hermetia illucens) has received global research interest and growing industrial application. Larvae farming conditions, such as temperature, pH, and moisture, have been critically examined. However, the substrate carbon to nitrogen ratio (C/N), one of the key parameters that may affect larval survival and bioconversion efficiency, is significantly less studied. The current study aimed to compare the nitrogen supplying effects of 9 nitrogen species (i.e., NH4Cl, NaNO3, urea, uric acid, Gly, L-Glu, L-Glu:L-Asp (1:1, w/w), soybean flour, and fish meal) during food waste larval treatment, and further examine the C/N effects on the larval development and bioconversion process, using the C/N adjustment with urea from the initial 21:1 to 18:1, 16:1, 14:1, 12:1, and 10:1, respectively. The food wastes were supplied with the same amount of nitrogen element (1 g N/100 g dry wt) in the nitrogen source trial and different amount of urea in the C/N adjustment trial following larvae treatment. The results showed that NH4Cl and NaNO3 caused significant harmful impacts on the larval survival and bioconversion process, while the 7 organic nitrogen species resulted in no significant negative effect. Further adjustment of C/N with urea showed that the C/N range between 18:1 and 14:1 was optimal for a high waste reduction performance (73.5-84.8%, p < 0.001) and a high larvae yield (25.3-26.6%, p = 0.015), while the C/N range of 18:1 to 16:1 was further optimal for an efficient larval protein yield (10.1-11.1%, p = 0.003) and lipid yield (7.6-8.1%, p = 0.002). The adjustment of C/N influenced the activity of antioxidant enzymes, such as superoxide dismutase (SOD, p = 0.015), whereas exerted no obvious impact on the larval amino acid composition. Altogether, organic nitrogen is more suitable than NH4Cl and NaNO3 as the nitrogen amendment during larval food waste treatment, addition of small amounts of urea, targeting C/N of 18:1-14:1, would improve the waste reduction performance, and application of C/N at 18:1-16:1 would facilitate the larval protein and lipid bioconversion process.

13.
Int J Biol Macromol ; 182: 1473-1483, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34019922

RESUMO

κ-Carrageenan oligosaccharides with many excellent biological properties could be produced by κ-carrageenases selectively. In this study, based on the encoding gene of full length κ-carrageenase obtained from Pseudoalteromonas sp. ZDY3 and the reported mature secreted κ-carrageenase composed of 275 amino acid residues (N26-T300), CgkPZ_GH16 was expressed in E. coli, but no soluble active protein could be detected. Fortunately, the signal peptide of wild-type κ-carrageenase was recognized, and cleaved in the soluble and folding form in E. coli, the Km and kcat values of CgkPZ_SP_GH16 was 1.007 mg/mL and 362.8 s-1. By molecular dynamics simulations, it was showed that YjdB domain might affect the activity of κ-carrageenase. Due to the absence of mature processing modification system in E. coli, YjdB was remained in recombinant full length κ-carrageenase, and the lost catalytic efficiency of CgkPZ was compensated by expression level and thermal stability. Interestingly, CgkPZ_GH16_YjdB was expressed soluble without the signal peptide, which indicated that YjdB could contribute to the expression and folding of κ-carrageenase. These results provide new insight into the effects of different modules of κ-carrageenase on the expression and properties of enzyme.


Assuntos
Proteínas de Bactérias/metabolismo , Escherichia coli/enzimologia , Glicosídeo Hidrolases/metabolismo , Oligossacarídeos/metabolismo , Pseudoalteromonas/enzimologia , Pseudoalteromonas/metabolismo , Proteínas de Bactérias/genética , Glicosídeo Hidrolases/genética
14.
Biotechnol Bioeng ; 118(7): 2597-2608, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33829485

RESUMO

Bacillus coagulans, a thermophilic facultative anaerobe, is a favorable chassis strain for the biosynthesis of desired products. In this study, B. coagulans was converted into an efficient malic acid producer by metabolic engineering and promoter engineering. Promoter mapping revealed that the endogenous promoter Pldh was a tandem promoter. Accordingly, a promoter library was developed, covering a wide range of relative transcription efficiencies with small increments. A reductive tricarboxylic acid pathway was established in B. coagulans by introducing the genes encoding pyruvate carboxylase (pyc), malate dehydrogenase (mdh), and phosphoenolpyruvate carboxykinase (pckA). Five promoters of various strengths within the library were screened to fine-tune the expression of pyc to improve the biosynthesis of malic acid. In addition, genes involved in the competitive metabolic pathways were deleted to focus the substrate and energy flux toward malic acid. Dual-phase fed-batch fermentation was performed to increase the biomass of the strain, further improving the titer of malic acid to 25.5 g/L, with a conversion rate of 0.3 g/g glucose. Our study is a pioneer research using promoter engineering and genetically modified B. coagulans for the biosynthesis of malic acid, providing an effective approach for the industrialized production of desired products using B. coagulans.


Assuntos
Bacillus coagulans , Proteínas de Bactérias , Ciclo do Ácido Cítrico , Malatos/metabolismo , Engenharia Metabólica , Regiões Promotoras Genéticas , Bacillus coagulans/genética , Bacillus coagulans/metabolismo , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética
15.
Electron J Biotechnol ; 49: 56-63, Jan. 2021. tab, ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1291900

RESUMO

BACKGROUND: 2R,3R-butanediol dehydrogenase (R-BDH) and other BDHs contribute to metabolism of 3R/3S-Acetoin (3R/3S-AC) and 2,3-butanediol (2,3-BD), which are important bulk chemicals used in different industries. R-BDH is responsible for oxidizing the hydroxyl group at their (R) configuration. Bacillus species is a promising producer of 3R/3S-AC and 2,3-BD. In this study, R-bdh gene encoding R-BDH from Bacillus sp. DL01 was isolated, expressed and identified. RESULTS: R-BDH exerted reducing activities towards Diacetyl (DA) and 3R/3S-AC using NADH, and oxidizing activities towards 2R,3R-BD and Meso-BD using NAD+ , while no activity was detected with 2S,3S-BD. The R-BDH showed its activity at a wide range of temperature (25 C to 65 C) and pH (5.0­8.0). The R-BDH activity was increased significantly by Cd2+ when DA, 3R/3S-AC, and Meso-BD were used as substrates, while Fe2+ enhanced the activity remarkably at 2R,3R-BD oxidation. Kinetic parameters of the R-BDH from Bacillus sp. DL01 showed the lowest Km, the highest Vmax, and the highest Kcat towards the racemic 3R/3S-AC substrate, also displayed low Km towards 2R,3R-BD and Meso-BD when compared with other reported R-BDHs. CONCLUSIONS: The R-BDH from Bacillus sp. DL01 was characterized as a novel R-BDH with high enantioselectivity for R-configuration. It considered NAD+ and Zn2+ dependant enzyme, with a significant affinity towards 3R/3S-AC, 2R,3R-BD, and Meso-BD substrates. Thus, R-BDH is providing an approach to regulate the production of 3R/3S-AC or 2,3-BD from Bacillus sp. DL01.


Assuntos
Bacillus subtilis/enzimologia , Oxirredutases do Álcool/isolamento & purificação , Oxirredutases do Álcool/metabolismo , Temperatura , Cinética , Concentração de Íons de Hidrogênio , Acetoína
16.
Environ Res ; 194: 110498, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33220246

RESUMO

Fe(III) oxides have been investigated to accelerate anaerobic methanogenic degradation of complex organic compounds. However, the critical role linked to the characteristics of different types of Fe(III) oxides is still unclear. Study presented here performed a side-by-side comparison of four types of Fe(III) oxides including Fe(III)-citrate, ferrihydrite, hematite and magnetite to evaluate their effectiveness in methanogenic degradation of phenol. Results showed that, amorphous Fe(III)-citrate group showed the fastest phenol degradation and Fe2+ release among all the groups, followed by poorly crystalline ferrihydrite. Although Fe(III)-citrate group also showed the fastest methane production rate, the efficiency of electron recovery in methane production was only 58-78%, which was evidently lower than that in both crystalline hematite (86-89%) and magnetite (93-97%) groups. Methane production rate with non-conductive ferrihydrite was nearly same as that with conductive magnetite, both of which were significantly higher than that with semi-conductive hematite. X-ray Diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analysis showed that sludge collected from hematite and magnetite group still respectively presented a relatively intact characteristic spectra involved in hematite and magnetite. Differently, the characteristic spectra involved in ferrihydrite was not evident in sludge collected from ferrihydrite group, whereas the characteristic spectra involved in magnetite was detected. Microbial community analysis showed that, both Fe(III)-citrate and ferrihydrite specially enriched Fe(III)-reducing bacteria capable of degrading phenol into fatty acids (Trichococcus and Caloramator) via dissimilatory Fe(III) reduction. Fe(III)-citrate also stimulated the growth of Syntrophus capable of degrading phenol/benzoate into acetate and proceeding direct interspecies electron transfer (DIET). In magnetite and hematite group, the abundance of Enterococcus species evidently increased, and they might proceed DIET with Methanothrix species in syntrophic conversion of fatty acids into methane.


Assuntos
Compostos Férricos , Óxidos , Anaerobiose , Óxido Ferroso-Férrico , Metano , Oxirredução
17.
Protein Expr Purif ; 178: 105768, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33035660

RESUMO

κ-Carrageenase (EC3.2.1.83) is a class of glycoside hydrolase, which can be used for hydrolysis of κ-carrageenan to κ-carrageenan oligosaccharides. In this study, a bacterium, identified as Pseudoalteromonas sp. ZDY3 isolated from rotten algae, was capable to degrade κ-carrageenan. The κ-carrageenase produced by Pseudoalteromonas sp. ZDY3 was purified to homogeneity and named as CgkZDY3. The accurate molecular mass of CgkZDY3 was determined through LC-HRMS, and a posttranslational removal of C-terminal end of the protein was discovered. CgkZDY3 had strict hydrolysis specificity to κ-carrageenan, the values of Km and kcat/Km of CgkZDY3 were 3.67 mg mL-1 and 53.0 mL mg-1 s-1, respectively. CgkZDY3 was a cold-adapted κ-carrageenase with excellent storage stability of both the temperature below 35 °C and a wide pH range, and was an endo-type κ-carrageenase with high hydrolysis rate, oligosaccharides with different degrees of polymerization can be obtained by controlling the hydrolysis time, and the final products were κ-neocarrabiose and κ-neocarratetraose. These properties are of great significance for production of κ-carrageenan oligosaccharides with different polymerization degrees under process control.


Assuntos
Aclimatação , Proteínas de Bactérias , Pseudoalteromonas/enzimologia , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Temperatura Baixa , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/isolamento & purificação
18.
Stem Cell Res Ther ; 11(1): 480, 2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33176873

RESUMO

BACKGROUND: Nontraumatic osteonecrosis of the femoral head (NONFH) is a highly disabling orthopedic disease in young individuals. Plasminogen activator inhibitor 1 (PAI-1) has been reported to be positively associated with NONFH. We aimed to investigate the dysregulating PAI-1 in bone marrow mesenchymal stem cells (BMMSCs) and vascular cells in rabbit steroid-induced NONFH. METHODS: To verify the hypothesis that BMMSCs could promote thrombus formation in a paracrine manner, we collected exosomes from glucocorticoid-treated BMMSCs (GB-Exo) to determine their regulatory effects on vascular cells. microRNA sequencing was conducted to find potential regulators in GB-Exo. Utilizing gain-of-function and knockdown approaches, we testified the regulatory effect of microRNA in exosomes. RESULTS: The expression of PAI-1 was significantly increased in the local microenvironment of the femoral head in the ONFH model. GB-Exo promoted PAI-1 expression in vascular smooth muscle cells and vascular endothelial cells. We also revealed that miR-451-5p in GB-Exo plays a crucial role for the elevated PAI-1. Moreover, we identified miR-133b-3p and tested its role as a potential inhibitor of PAI-1. CONCLUSIONS: This study provided considerable evidence for BMMSC exosomal miR-mediated upregulation of the fibrinolytic regulator PAI-1 in vascular cells. The disruption of coagulation and low fibrinolysis in the femoral head will eventually lead to a disturbance in the microcirculation of NONFH. We believe that our findings could be of great significance for guiding clinical trials in the future.


Assuntos
Exossomos , Células-Tronco Mesenquimais , MicroRNAs , Osteonecrose , Animais , Células Endoteliais , Cabeça do Fêmur , MicroRNAs/genética , Osteonecrose/genética , Inibidor 1 de Ativador de Plasminogênio/genética , Coelhos
19.
Molecules ; 25(21)2020 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-33114310

RESUMO

Pleurotus ostreatus is one of the widely cultivated edible fungi across the world. Mycelial subculture is an indispensable part in the process of cultivation and production for all kinds of edible fungi. However, successive subcultures usually lead to strain degeneration. The degenerated strains usually have a decrease in stress resistance, yield, and an alteration in fruiting time, which will subsequently result in tremendous economic loss. Through proteomic analysis, we identified the differentially expressed proteins (DEPs) in the mycelium of Pleurotus ostreatus from different subcultured generations. We found that the DNA damage repair system, especially the double-strand breaks (DSBs), repairs via homologous recombination, was impaired in the subcultured mycelium, and gradual accumulation of the DSBs would lead to the strain degeneration after successive subculture. The TUNEL assay further confirmed our finding about the DNA breaks in the subcultured mycelium. Interestingly, the enzyme activity of laccase, carboxylic ester hydrolase, α-galactosidase, and catalase directly related to passage number could be used as the characteristic index for strain degeneration determination. Our results not only reveal for the first time at the molecular level that genomic instability is the cause of degeneration, but also provide an applicable approach for monitoring strain degeneration in process of edible fungi cultivation and production.


Assuntos
Extratos Celulares/química , Carpóforos/metabolismo , Proteínas Fúngicas/genética , Micélio/enzimologia , Pleurotus/química , Proteômica/métodos , Carboxilesterase/genética , Carboxilesterase/metabolismo , Catalase/genética , Catalase/metabolismo , Células Cultivadas , Estabilidade Enzimática , Indústria Alimentícia , Proteínas Fúngicas/metabolismo , Lacase/genética , Lacase/metabolismo , Espectrometria de Massas em Tandem , alfa-Galactosidase/genética , alfa-Galactosidase/metabolismo
20.
Biomed Pharmacother ; 127: 110163, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32380388

RESUMO

Predominant health impacts from alcoholism are chronic neurologic deficits and hepatic dysfunction. Pueraria extract (PE) is a solution obtained from the dried root of Pueraria lobate and can reverse alcohol-induced hepatic damage. The present study aimed to elucidate the effects of PE on ethanol-induced injury in microglia and neurons. To confirm the reliability of the experimental approach, an in vivo demonstration of PE activity was used to verify its impact on hepatic damage in mice exposed to ethanol (ETOH). Subsequently, an in vitro assay was used to verify the effects of PE on ETOH-exposed microglia and neurons.PE reversed fibrosis and hyperplasia, adipocyte infiltration, hepatomegaly, hepatic function, lipid metabolism, indicators of oxidative stress, and morphological changes in hepatic cells, induced by ETOH exposure. The reliability of the experimental approach was thus confirmed. PE also reversed the activation of microglia and inflammatory-related cytokines and proteins induced by ETOH exposure. PE showed protective effects on neurons via inhibition of mitochondrial fission. in vivo and in vitro evidence indicated that PE might be useful in the treatment of both hepatic injury and neurologic deficits commonly observed in chronic alcoholism.


Assuntos
Alcoolismo/tratamento farmacológico , Microglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Extratos Vegetais/farmacologia , Pueraria/química , Alcoolismo/complicações , Animais , Citocinas/metabolismo , Etanol/toxicidade , Hepatopatias Alcoólicas/complicações , Hepatopatias Alcoólicas/tratamento farmacológico , Masculino , Camundongos , Microglia/patologia , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Reprodutibilidade dos Testes
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