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1.
PeerJ ; 12: e17282, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38666083

RESUMO

This study investigated the potential of using steam-exploded oil palm empty fruit bunches (EFB) as a renewable feedstock for producing fumaric acid (FA), a food additive widely used for flavor and preservation, through a separate hydrolysis and fermentation process using the fungal isolate K20. The efficiency of FA production by free and immobilized cells was compared. The maximum FA concentration (3.25 g/L), with 0.034 g/L/h productivity, was observed after incubation with the free cells for 96 h. Furthermore, the production was scaled up in a 3-L air-lift fermenter using oil palm EFB-derived glucose as the substrate. The FA concentration, yield, and productivity from 100 g/L initial oil palm EFB-derived glucose were 44 g/L, 0.39 g/g, and 0.41 g/L/h, respectively. The potential for scaling up the fermentation process indicates favorable results, which could have significant implications for industrial applications.


Assuntos
Células Imobilizadas , Fermentação , Fumaratos , Fumaratos/metabolismo , Células Imobilizadas/metabolismo , Óleo de Palmeira , Frutas/microbiologia , Frutas/química , Arecaceae/microbiologia , Arecaceae/química , Óleos de Plantas/metabolismo , Hidrólise , Glucose/metabolismo
2.
J Chromatogr A ; 1721: 464845, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38552371

RESUMO

Non-Hodgkin lymphoma (NHL) is a heterogeneous group of malignant tumors occurring in B or T lymphocytes, and no small molecule-positive drugs to treat NHL have been marketed. Cluster of differentiation 20 (CD20) is an important molecule regulating signaling for the life and differentiation of B lymphocytes and possesses the characteristics of a drug target for treating NHL. 2-Methoxyestradiol induces apoptosis in lymphoma Raji cells and CD20 protein is highly expressed by Raji lymphoma cells. Therefore, in this study, a CD20-SNAP-tag/CMC model was developed to validate the interaction of 2-methoxyestradiol with CD20. 2-Methoxyestradiol was used as a small molecule control compound, and the system was validated for good applicability. The cell membrane chromatography model was combined with high-performance liquid chromatography ion trap time-of-flight mass spectroscopy (HPLC-IT-TOF-MS) in a two-dimensional system to successfully identify, analyze, and characterize the potential active compounds of Schisandra chinensis (Turcz.) Baill. extract and Lysionotus pauciflorus Maxim. extract, including Schisandrin A, Schizandrol A, Schizandrol B, Schisantherin B, and Nevadensin, which can act on CD20 receptors. The five potential active compounds were analyzed by non-linear chromatography. The thermodynamic and kinetic parameters of their interaction with CD20 were also analyzed, and the mode of interaction was simulated by molecular docking. Their inhibitory effects on lymphoma cell growth were assessed using a Cell Counting Kit-8 (CCK-8). Nevadensin and Schizandrin A were able to induce apoptosis in Raji cells within a certain concentration range. In conclusion, the present experiments provide some bases for improving NHL treatment and developing small molecule lead compounds targeting CD20 with low toxicity and high specificity.


Assuntos
Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas , Humanos , 2-Metoxiestradiol , Células Imobilizadas/química , Cromatografia Líquida de Alta Pressão/métodos , Ciclo-Octanos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Cromatografia Gasosa-Espectrometria de Massas , Lignanas/análise , Linfoma/tratamento farmacológico , Medicina Tradicional Chinesa , Simulação de Acoplamento Molecular , Compostos Policíclicos , Schisandra/química
3.
J Hazard Mater ; 465: 133503, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38228007

RESUMO

Uranium (U) contamination is hazardous to human health and the environment owing to its radiotoxicity and chemical toxicity and needs immediate attention. In this study, the immobilized biomass of Chryseobacterium sp. strain PMSZPI isolated from U enriched site, was investigated for U(VI) biomineralization in batch and column set-up. Under batch mode, the fresh or lyophilized cells successfully entrapped in calcium alginate beads demonstrated effectual U precipitation under acid and alkaline conditions. The maximum removal was detected at pH 7 wherein ∼98-99% of uranium was precipitated from 1 mM uranyl carbonate solution loading ∼350 mg U/g of biomass within 24 h in the presence of organic phosphate substrate. The resulting uranyl phosphate precipitates within immobilized biomass loaded beads were observed by SEM-EDX and TEM while the formation of U biomineral was confirmed by FTIR and XRD. Retention of phosphatase activity without any loss of uranium precipitation ability was observed for alginate beads with lyophilized biomass stored for 90 d at 4 °C. Continuous flow through experiment with PMSZPI biomass immobilized in polyacrylamide gel exhibited U loading of 0.8 g U/g of biomass at pH 7 using 1 l of 1 mM uranyl solution. This investigation established the feasibility for the application of immobilized PMSZPI biomass for field studies. ENVIRONMENTAL IMPLICATION: Uranium contamination is currently a serious environmental concern owing to anthropogenic activities and needs immediate attention. We have developed here a biotechnological method for successful uranium removal using immobilized cells of a uranium tolerant environmental bacterium, Chryseobacterium sp. strain PMSZPI isolated from U ore deposit via phosphatase enzyme mediated uranium precipitation. The ability of immobilized PMSZPI cells to precipitate U(VI) as long-term stable U phosphates under environmental conditions relevant for contaminated waters containing high concentrations of U that exerts toxicity for biological systems is explored here. The long term stability of the immobilized biomass without compromising its U removal capacity shows the relevance of the bioremediation strategy for uranium contamination proposed in this work.


Assuntos
Chryseobacterium , Urânio , Humanos , Biomineralização , Células Imobilizadas , Monoéster Fosfórico Hidrolases
4.
J Environ Manage ; 326(Pt A): 116729, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36375423

RESUMO

Among the various techniques used to clean up polluted environments, bioremediation is the most cost-effective and eco-friendly option. The diversity of microbial communities in a consortium can significantly affect the biodegradability of hazardous organic pollutants, particularly for in situ bioremediation processes. This is largely attributed to interactions between members of a consortium. In this study, the effect of internal diffusion limitations in substrate model biodegradation was firstly examined by immobilized bacterial cells at different particle sizes produced by the electrospray technique. According to the obtained results, for particles with large size, the effectiveness factors (η) were about 0.58-0.67, and the resistance to diffusive on the biodegradation rate was significant, while with decreasing the particle size, η increases and approaches about 1. After selection of suitable bead size, heavy crude oil biodegradation was investigated using a consortium consisting of three oil-degrading bacterial strains at different treatment systems. The removal rate in the suspended co-culture system stands at minimum value of 38% with all three strains which is an indicator of negative interactions among consortium members. Independent immobilization of microorganisms minimizes the competition and antagonistic interactions between strains and leads to more crude oil removal, so that, the biodegradation rate reached 60%.


Assuntos
Poluição por Petróleo , Petróleo , Petróleo/metabolismo , Biodegradação Ambiental , Bactérias/metabolismo , Células Imobilizadas/metabolismo
5.
Sci Rep ; 11(1): 12990, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34155247

RESUMO

Exiguobacterium sp. AO-11 was immobilized on bio-cord at 109 CFU g-1 carrier for the removal of crude oil from marine environments. To prepare a ready-to-use bioremediation product, the shelf life of the immobilized cells was calculated. Approximately 90% of 0.25% (v/v) crude oil removal was achieved within 9 days when the starved state of immobilized cells was used. The oil removal activity of the immobilized cells was maintained in the presence of oil dispersant (89%) and at pH values of 7-9. Meanwhile, pH, oil concentration and salinity affected the oil removal efficacy. The immobilized cells could be reused for at least 5 cycles. The Arrhenius equation describing the relationship between the rate of reaction and temperature was validated as a useful model of the kinetics of retention of activity by an immobilized biocatalyst. It was estimated that the immobilized cells could be stored in a non-vacuum bag containing phosphate buffer (pH 7.0) at 30 °C for 39 days to retain the cells at 107 CFU g-1 carrier and more than 50% degradation activity. These results indicated the potential of using bio-cord-immobilized crude oil-degrading Exiguobacterium sp. AO-11 as a bioremediation product in a marine environment.


Assuntos
Biodegradação Ambiental , Exiguobacterium/metabolismo , Petróleo/metabolismo , Biofilmes , Biotransformação , Células Imobilizadas/metabolismo , Células Imobilizadas/ultraestrutura , Exiguobacterium/crescimento & desenvolvimento , Exiguobacterium/ultraestrutura , Concentração de Íons de Hidrogênio , Poluição por Petróleo , Salinidade
6.
ACS Appl Mater Interfaces ; 13(13): 15031-15039, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33764744

RESUMO

Enrichment of rare cancer cells from various cell mixtures for subsequent analysis or culture is essential for understanding cancer formation and progression. In particular, maintaining the viability of captured cancer cells and gently releasing them for relevant applications remain challenging for many reported methods. Here, a physically cross-linked deoxyribozyme (DNAzyme)-based hydrogel strategy was developed for the specific envelopment and release of targeted cancer cells, allowing the aptamer-guided capture, 3D envelopment, and Zn2+-dependent release of viable cancer cells. The DNAzyme hydrogel is constructed through the intertwinement and hybridization of two complementary DNAzyme strands located on two rolling circle amplification-synthesized ultralong DNA chains. The enveloping and separation of target cells were achieved during the formation of the DNAzyme hydrogel (sol-gel transition). Triggered by Zn2+, the encapsulated cells can be gently released from the dissociated DNAzyme hydrogel with high viability (gel-sol transition). Successful isolations of target cells from cancer cell mixtures and peripheral blood mononuclear cells (PBMC) were demonstrated. This method offers an attractive approach for the separation of target cancer cells for various downstream applications that require viable cells.


Assuntos
Células Imobilizadas/citologia , DNA Catalítico/química , Hidrogéis/química , Transição de Fase , Aptâmeros de Nucleotídeos/química , Linhagem Celular Tumoral , Células Imobilizadas/química , Humanos , Neoplasias/patologia , Zinco/química
7.
Anal Bioanal Chem ; 413(4): 1107-1116, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33388846

RESUMO

This paper proposes the use of Anoxybacillus flavithermus SO-15 immobilized on iron oxide nanoparticles (NPs) as a novel magnetized biosorbent for the preconcentrations of uranium (U) and thorium (Th). The SPE procedure was based on biosorption of U(VI) and Th(IV) on a column of iron oxide NPs loaded with dead and dried thermophilic bacterial biomass prior to U(VI) and Th(IV) measurements by ICP-OES. The biosorbent characteristicswere explored using FT-IR, SEM, and EDX. Significant operational factors such as solution pH, volume and flow rate of the sample solution, amounts of dead bacteria and iron oxide nanoparticles, matrix interference effect, eluent type, and repeating use of the biosorbent on process yield were studied. The biosorption capacities were found as 62.7 and 56.4 mg g-1 for U(VI) and Th(IV), respectively. The novel extraction process has been successfullyapplied to the tap, river, and lake water samples for preconcentrations of U(VI) and Th(IV).


Assuntos
Anoxybacillus/química , Nanopartículas Magnéticas de Óxido de Ferro/química , Extração em Fase Sólida/métodos , Tório/isolamento & purificação , Urânio/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Células Imobilizadas/química
8.
Mol Cell Endocrinol ; 519: 111039, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32980418

RESUMO

Previous studies have demonstrated that the transplantation of alginate-poly-ʟ-lysine-alginate (APA)-encapsulated rat Leydig cells (LCs) provides a promising approach for treating testosterone deficiency (TD). Nevertheless, LCs have a limited capacity to proliferate, limiting the efficacy of LC transplantation therapy. Here, we established an efficient differentiation system to obtain functional Leydig-like cells (LLCs) from human stem Leydig cells (hSLCs). Then we injected APA-encapsulated LLCs into the abdominal cavities of castrated mice without an immunosuppressor. The APA-encapsulated cells survived and partially restored testosterone production for 90 days in vivo. More importantly, the transplantation of encapsulated LLCs ameliorated the symptoms of TD, such as fat accumulation, muscle atrophy and adipocyte accumulation in bone marrow. Overall, these results suggest that the transplantation of encapsulated LLCs is a promising new method for testosterone supplementation with potential clinical applications in TD.


Assuntos
Células Imobilizadas/transplante , Células Intersticiais do Testículo/transplante , Testosterona/deficiência , Adipócitos/patologia , Adolescente , Adulto , Idoso , Alginatos/química , Antígenos CD/metabolismo , Medula Óssea/patologia , Cápsulas , Castração , Diferenciação Celular , Humanos , Células Intersticiais do Testículo/ultraestrutura , Masculino , Pessoa de Meia-Idade , Atrofia Muscular/patologia , Polilisina/análogos & derivados , Polilisina/química , Testosterona/metabolismo , Adulto Jovem
9.
Int J Phytoremediation ; 23(5): 454-461, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32976718

RESUMO

Palm oil mill effluent (POME) has high chemical oxygen demand (COD), thus requires effective treatments to environmentally benign levels before discharge. In this study, immobilized microalgae cells are used for removing pollutants in treated palm oil mill effluent (TPOME). Different ratios of microalgae beads to TPOME concentration were examined at 1:2.5, 1:5, and 1:10. The biomass concentration and COD removal were measured through a standard method. The color of the cultivated microalgae beads changed from light green to darker green after the POME treatment for 9 days, hence demonstrating that microalgae cells were successfully grown inside the beads with pH up to 9.84. The immobilized cells cultivated in the POME at 1:10 achieved a higher biomass concentration of 1.268 g/L and a COD removal percentage of 72% than other treatment ratios. The increment of the ratio of microalgae cells beads to POME concentration did not cause any improvement in COD removal efficiency. This was due to the inhibitory effect of self-shading resulting in the slow growth rate of microalgae cells which responsible for low COD removal. Therefore, this system could be a viable technology for simultaneous biomass production and POME treatment. This will contribute to research efforts toward the development of new and improved technologies in treating POME.


Assuntos
Poluentes Ambientais , Resíduos Industriais , Alginatos , Biodegradação Ambiental , Células Imobilizadas/química , Resíduos Industriais/análise , Óleo de Palmeira , Óleos de Plantas , Eliminação de Resíduos Líquidos
10.
Biochem Biophys Res Commun ; 528(4): 650-657, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32513541

RESUMO

INTRODUCTION: The extension of islet transplantation to a wider number of type 1 diabetes patients is compromised by severe adverse events related to the immunosuppressant therapy required for allogenic islet transplantation. In this context, microencapsulation offers the prospects of immunosuppressive-free therapy by physically isolating islets from the immune system. However, current biomaterials need to be optimized to: improve biocompatibility, guaranty the maintenance of graft viability and functionality, and prevent fibrosis overgrowth around the capsule in vivo. Accumulating evidence suggest that mesenchymal stem cells (MSCs) and anchor points consisting of tripeptides arg-gly-asp (RGD) have cytoprotective effects on pancreatic islets. Here, we investigated the effect of supplementing reference M-rich alginate microcapsules with MSCs and RGD-G rich alginate on bioprocessing as well as on human pancreatic islets viability and functionality. METHODS: We characterized the microcapsules components, and then for the new microcapsule composite product: we analyzed the empty capsules biocompatibility and then investigated the benefits of MSCs and RGD-G rich alginate on viability and functionality on the encapsulated human pancreatic islets in vitro. We performed viability tests by confocal microscopy and glucose stimulated insulin secretion (GSIS) test in vitro to assess the functionality of naked and encapsulated islets. RESULTS: Encapsulation in reference M-rich alginate capsules induced a reduction in viability and functionality compared to naked islets. This side-effect of encapsulation was in part counteracted by the presence of MSCs but the restoration was complete with the combination of both MSCs and the RGD-G rich alginate. CONCLUSIONS: The present findings show that bioprocessing a favorable composite environment inside the M-rich alginate capsule with both MSCs and RGD-G rich alginate improves human islets survival and functionality in vitro.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Células Imobilizadas/citologia , Ilhotas Pancreáticas/citologia , Células-Tronco Mesenquimais/citologia , Oligopeptídeos/farmacologia , Adulto , Alginatos/química , Células Cultivadas , Células Imobilizadas/efeitos dos fármacos , Humanos , Ilhotas Pancreáticas/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Pessoa de Meia-Idade
11.
Probiotics Antimicrob Proteins ; 12(4): 1370-1384, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32246325

RESUMO

In the current study, we investigated the effect of a probiotic bacterium (Lactobacillus rhamnosus ATCC 7469) microencapsulated with alginate and hi-maize starch and coated with chitosan on improving growth factors, body composition, blood chemistry, and the immune response of rainbow trout (initial weight: 18.41 ± 0.32 g). Four experimental diets were formulated to feed fish for 60 days. They were control diet without any additive (C), diet added with beads without probiotic (E), a probiotic sprayed to the diet (L.r), and encapsulated probiotic supplemented diet (E-L.r). The results indicated that feeding with E-Lr significantly improved weight gain (84.98 g) and feed conversion ratio (0.95) compared to the other groups (P < 0.05). Also, fish fed E-Lr diet had a significantly higher value of whole-body protein (17.51%), total protein in the blood (4.98 g/dL), lysozyme (30.66 U/mL), alternative complement pathway hemolytic activity (134 U/mL), superoxide dismutase (203 U/mg protein), and catalase (528.33 U/mg protein) (P < 0.05) as compared to those fed the control diet. Similarly, a higher relative expression of immune-related genes such as interleukin-1 (Il-1) and tumor necrosis factor-alpha (TNF-1α) were reported in those fed E-L.r and L.r diets respectively. Interestingly, the fish fed dietary E-L.r had a significantly lower value of lipid in the whole body (4.82%) and cholesterol in the blood (160.67%) in comparison with those fed the control diet (P < 0.05). At the end of the experiment, all groups were challenged by Yersinia ruckeri where the survival rate of rainbow trout fed dietary E-L.r (70.36%) was statistically higher than that of the others (P < 0.05). Overall, the results suggested that encapsulated probiotic Lact. rhamnosus ATCC 7469 acted better than unencapsulated probiotic and has a potential to improve growth performance, flesh quality, and the immune response of rainbow trout.


Assuntos
Doenças dos Peixes/terapia , Proteínas de Peixes/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Lacticaseibacillus rhamnosus/fisiologia , Oncorhynchus mykiss/imunologia , Probióticos/farmacologia , Yersiniose/terapia , Alginatos/química , Ração Animal/análise , Animais , Composição Corporal/efeitos dos fármacos , Catalase/genética , Catalase/imunologia , Encapsulamento de Células/métodos , Células Imobilizadas , Quitosana/química , Colesterol/sangue , Via Alternativa do Complemento/efeitos dos fármacos , Dieta , Resistência à Doença/efeitos dos fármacos , Resistência à Doença/genética , Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Proteínas de Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Interleucina-1/genética , Interleucina-1/imunologia , Muramidase/genética , Muramidase/imunologia , Oncorhynchus mykiss/crescimento & desenvolvimento , Oncorhynchus mykiss/microbiologia , Superóxido Dismutase/genética , Superóxido Dismutase/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Aumento de Peso/efeitos dos fármacos , Yersiniose/imunologia , Yersiniose/microbiologia , Yersinia ruckeri/efeitos dos fármacos , Yersinia ruckeri/crescimento & desenvolvimento , Yersinia ruckeri/patogenicidade
12.
J Hazard Mater ; 390: 121493, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32081488

RESUMO

Metribuzin (MB) is a triazinone herbicide used for the eradication of weeds in agriculture. Presence of its residues in agricultural soil can potentially harm the establishment of subsequent crops and structure of soil microbial populations. In this study, remediation potential of an MB degrading bacterial consortium MB3R immobilized on biochar was evaluated in potato vegetated soil. In potato vegetated soil augmented with MB3R alone and MB3R immobilized on biochar, 82 and 96% MB degradation was recorded respectively as compared to only 29.3% in un-augmented soil. Kinetic parameters revealed that MB3R immobilized biochar is highly proficient as indicated by significant increase in the rate of biodegradation and decrease in half-life of MB. Enhanced plant growth was observed when augmented with bacterial consortium either alone or immobilized on biochar. Presence of herbicide negatively affected the soil bacterial community structure. However, MB3R immobilized on biochar proved to be helpful for restoration of soil bacterial community structure affected by MB. This is the very first report that reveals improved remediation of contaminated soil and restoration of soil bacterial populations by use of the MB degrading bacterial consortium immobilized on biochar.


Assuntos
Bacillus/metabolismo , Células Imobilizadas/metabolismo , Herbicidas/metabolismo , Rhodococcus/metabolismo , Poluentes do Solo/metabolismo , Triazinas/metabolismo , Biodegradação Ambiental , Carvão Vegetal , Microbiota , Microbiologia do Solo , Solanum tuberosum
13.
Chemosphere ; 239: 124724, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31505447

RESUMO

Combination of sulfuric acid modified bagasse activated carbon-bone biochar beads and Acinetobacter indicus screened from petroleum contaminated soil was the best condition for gaseous methyl tert-butyl ether (MTBE) removal. It was found that H2SO4 modified bagasse AC in powder form had higher adsorption capacity (989.33 mg g-1) than that in bead form (1.94 mg g-1). In addition, bone biochar in powder form (3.51 mg g-1) also had higher adsorption capacity than that in bead form (1.63 mg g-1). This was the fact that material beads contained high moisture content that inhibited the penetration of gaseous MTBE into the material. And a mixed material of H2SO4 modified bagasse AC-bone biochar beads had the highest adsorption capacity (2.22 mg g-1) compared to individual H2SO4 modified bagasse AC beads (1.94 mg g-1) and bone biochar beads (1.63 mg g-1) due to a mixed material had more rough surface and high surface area on its material. So, gaseous MTBE can penetrate through this material more easily. Although the maximum adsorption capacity of H2SO4 modified bagasse AC in powder form was the highest but microorganism cannot sustain and survive in this form for a long time. Therefore, the material beads were more suitable for microorganism to grow and degrade gaseous MTBE. Microorganism can degrade MTBE and caused no secondary wastes. Moreover, A. indicus was a novel strain for MTBE removal that has not been previously reported. Therefore, a combination of A. indicus-mixed material beads was a good choice for MTBE removal in a biofilter system.


Assuntos
Acinetobacter/metabolismo , Celulose/química , Carvão Vegetal/química , Éteres Metílicos/química , Acinetobacter/isolamento & purificação , Adsorção , Biodegradação Ambiental , Células Imobilizadas , Poluição Ambiental , Gases , Éteres Metílicos/isolamento & purificação , Éteres Metílicos/metabolismo , Petróleo , Microbiologia do Solo , Ácidos Sulfúricos/química , Gerenciamento de Resíduos/métodos
14.
Bioelectromagnetics ; 41(1): 41-51, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31736106

RESUMO

Magnetic fields (MFs) have been used as an external stimulus to increase cell proliferation in chondrocytes and extracellular matrix (ECM) synthesis of articular cartilage. However, previously published studies have not shown that MFs are homogeneous through cell culture systems. In addition, variables such as stimulation times and MF intensities have not been standardized to obtain the best cellular proliferative rate or an increase in molecular synthesis of ECM. In this work, a stimulation device, which produces homogeneous MFs to stimulate cell culture surfaces was designed and manufactured using a computational model. Furthermore, an in vitro culture of primary rat chondrocytes was established and stimulated with two MF schemes to measure both proliferation and ECM synthesis. The best proliferation rate was obtained with an MF of 2 mT applied for 3 h, every 6 h for 8 days. In addition, the increase in the synthesis of glycosaminoglycans was statistically significant when cells were stimulated with an MF of 2 mT applied for 5 h, every 6 h for 8 days. These findings suggest that a stimulation with MFs is a promising tool that could be used to improve in vitro treatments such as autologous chondrocyte implantation, either to increase cell proliferation or stimulate molecular synthesis. Bioelectromagnetics. 2020;41:41-51 © 2019 Bioelectromagnetics Society.


Assuntos
Cartilagem Articular/metabolismo , Condrócitos/citologia , Condrócitos/metabolismo , Matriz Extracelular/metabolismo , Campos Magnéticos/efeitos adversos , Animais , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Células Imobilizadas , Simulação por Computador , Glicosaminoglicanos/química , Ratos , Ratos Wistar , Propriedades de Superfície , Temperatura , Fatores de Tempo
15.
J Biotechnol ; 306: 81-88, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31585130

RESUMO

The valorization of a solid carob waste from the Lebanese industry was investigated by optimizing the production of lactic acid using immobilized Lactobacillus rhamnosus in alginate beads and response surface methodology. The results showed that pH and alginate concentration had a significant effect on the production of lactic acid. The fermentation of non-enriched carob waste juice needed an additional nitrogen source to improve lactic acid production and yield. From extracts with 65 g/L sugars, the optimum conditions were found to be 2% for the concentration of alginate, 4% bacteria cells entrapped in beads, 80 rpm agitation speed and pH 6.4. Lactic acid concentration obtained under these conditions was 22 g/L with a yield of 76.9 g/g consumed sugar and a productivity of 1.22 g/L/h. The use of invertase pretreatment increased lactic acid concentration from 22 to 40 g/L, but reduced yield at 66.6%. Finally, cells immobilized in alginate beads could be used for at least five successive cycles.


Assuntos
Indústria Alimentícia , Ácido Láctico/biossíntese , Lacticaseibacillus rhamnosus/metabolismo , Lotus/metabolismo , Eliminação de Resíduos/métodos , Alginatos/química , Células Imobilizadas , Conservação dos Recursos Naturais , Fermentação , Frutas/química , Frutas/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Lacticaseibacillus rhamnosus/citologia , Lotus/química , Nitrogênio/metabolismo , Extratos Vegetais/química , Extratos Vegetais/metabolismo
16.
Analyst ; 144(19): 5755-5765, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31433410

RESUMO

The bacterial toxin botulinum neurotoxin A (BoNT/A) is not only an extremely toxic substance but also a potent pharmaceutical compound that is used in a wide spectrum of neurological disorders and cosmetic applications. The quantification of the toxin is extremely challenging due to its extraordinary high physiological potency and is further complicated by the toxin's three key functionalities that are necessary for its activity: receptor binding, internalization-translocation, and catalytic activity. So far, the industrial standard to measure the active toxin has been the mouse bioassay (MBA) that is considered today as outdated due to ethical issues. Therefore, recent introductions of cell-based assays were highly anticipated; their impact however remains limited due to their labor-intensive implementation. This report describes a new in vitro approach that combines a nanosensor based on the use of nerve cell-mimicking nanoreactors (NMN) with microfluidic technology. The nanosensor was able to measure all three key functionalities, and therefore suitable to quantify the amount of physiologically active BoNT/A. The integration of such a sensor in a microfluidic device allowed the detection and quantification of BoNT/A amounts in a much shorter time than the MBA (<10 h vs. 2-4 days). Lastly, the system was also able to reliably quantify physiologically active BoNT/A within a simple final pharmaceutical formulation. This complete in vitro testing system and its unique combination of a highly sensitive nanosensor and microfluidic technology represent a significant ethical advancement over in vivo measures and a possible alternative to cell-based in vitro detection methods.


Assuntos
Materiais Biomiméticos , Toxinas Botulínicas Tipo A/análise , Células Imobilizadas , Dispositivos Lab-On-A-Chip , Nanoestruturas , Neurônios , Animais , Técnicas Biossensoriais , Medicamentos de Ervas Chinesas/química , Técnicas In Vitro/métodos , Lipossomos/química , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Ligação Proteica , Albumina Sérica Humana/química , Ressonância de Plasmônio de Superfície , Suínos
17.
Mar Pollut Bull ; 146: 741-750, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426216

RESUMO

Hydrocarbonoclastic bacterial consortium that utilizes crude oil as carbon and energy source was isolated from marine sediment collected at a depth of 2100 m. Molecular characterization by 16S rRNA gene sequences confirmed that these isolates as Oceanobacillus sp., Nesiotobacter sp., Ruegeria sp., Photobacterium sp., Enterobacter sp., Haererehalobacter sp., Exiguobacterium sp., Acinetobacter sp. and Pseudoalteromonas sp. Self-immobilized consortium degraded more than 85% of total hydrocarbons after 10 days of incubation with 1% (v/v) of crude oil and 0.05% (v/v) of Tween 80 (non-ionic surfactant) at 28 ±â€¯2 °C. The addition of nitrogen and phosphorus sources separately i.e. 0.1% (v/v) of CO (NH2)2 or K2HPO4 enhanced the hydrocarbon utilization percentage. The pathways of microbial degradation of hydrocarbons were confirmed by FTIR, GC-MS, 1H and 13C NMR spectroscopy analyses. These results demonstrated a novel approach using hydrocarbonoclastic self-immobilized deep sea bacterial consortium for eco-friendly bioremediation.


Assuntos
Sedimentos Geológicos/microbiologia , Consórcios Microbianos/fisiologia , Petróleo/metabolismo , Acinetobacter/genética , Acinetobacter/metabolismo , Biodegradação Ambiental , Células Imobilizadas , Fibras na Dieta/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos/metabolismo , Oceano Índico , Espectroscopia de Ressonância Magnética , Consórcios Microbianos/genética , Nitrogênio/metabolismo , Fósforo/metabolismo , Pseudoalteromonas/genética , Pseudoalteromonas/metabolismo , RNA Ribossômico 16S/genética , Rhodobacteraceae/genética , Rhodobacteraceae/metabolismo , Água do Mar/microbiologia , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Biosens Bioelectron ; 141: 111435, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31238280

RESUMO

Existing at the interface of biology and electronics, living cells have been in use as biorecognition elements (bioreceptors) in biosensors since the early 1970s. They are an interesting choice of bioreceptors as they allow flexibility in determining the sensing strategy, are cheaper than purified enzymes and antibodies and make the fabrication relatively simple and cost-effective. And with advances in the field of synthetic biology, microfluidics and lithography, many exciting developments have been made in the design of cell-based biosensors in the last about five years. 3D cell culture systems integrated with electrodes are now providing new insights into disease pathogenesis and physiology, while cardiomyocyte-integrated microelectrode array (MEA) technology is set to be standardized for the assessment of drug-induced cardiac toxicity. From cell microarrays for high-throughput applications to plasmonic devices for anti-microbial susceptibility testing and advent of microbial fuel cell biosensors, cell-based biosensors have evolved from being mere tools for detection of specific analytes to multi-parametric devices for real time monitoring and assessment. However, despite these advancements, challenges such as regeneration and storage life, heterogeneity in cell populations, high interference and high costs due to accessory instrumentation need to be addressed before the full potential of cell-based biosensors can be realized at a larger scale. This review summarizes results of the studies that have been conducted in the last five years toward the fabrication of cell-based biosensors for different applications with a comprehensive discussion on the challenges, future trends, and potential inputs needed for improving them.


Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas de Cultura de Células/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Animais , Técnicas Biossensoriais/métodos , Técnicas de Cultura de Células/métodos , Células Imobilizadas/citologia , Células Imobilizadas/metabolismo , Avaliação Pré-Clínica de Medicamentos/instrumentação , Avaliação Pré-Clínica de Medicamentos/métodos , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Desenho de Equipamento , Humanos , Técnicas Analíticas Microfluídicas/métodos
19.
Stem Cell Reports ; 12(6): 1260-1268, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31155505

RESUMO

Lymph nodes (LNs) are secondary lymphoid tissues that play a critical role in filtering the lymph and promoting adaptive immune responses. Surgical resection of LNs, radiation therapy, or infections may damage lymphatic vasculature and compromise immune functions. Here, we describe the generation of functional synthetic lympho-organoids (LOs) using LN stromal progenitors and decellularized extracellular matrix-based scaffolds, two basic constituents of secondary lymphoid tissues. We show that upon transplantation at the site of resected LNs, LOs become integrated into the endogenous lymphatic vasculature and efficiently restore lymphatic drainage and perfusion. Upon immunization, LOs support the activation of antigen-specific immune responses, thus acquiring properties of native lymphoid tissues. These findings provide a proof-of-concept strategy for the development of functional lympho-organoids suitable for restoring lymphatic and immune cell functions.


Assuntos
Células Imobilizadas , Matriz Extracelular , Linfonodos , Organoides , Regeneração , Alicerces Teciduais/química , Animais , Células Imobilizadas/metabolismo , Células Imobilizadas/transplante , Matriz Extracelular/química , Matriz Extracelular/transplante , Linfonodos/metabolismo , Linfonodos/transplante , Camundongos , Camundongos Transgênicos , Organoides/metabolismo , Organoides/transplante
20.
Biotechnol J ; 14(8): e1800624, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31161690

RESUMO

The fungal endophyte Cyanodermella asteris (C. asteris) has been recently isolated from the medicinal plant Aster tataricus (A. tataricus). This fungus produces astin C, a cyclic pentapeptide with anticancer and anti-inflammatory properties. The production of this secondary metabolite is compared in immobilized and planktonic conditions. For immobilized cultures, a stainless steel packing immersed in the culture broth is used as a support. In these conditions, the fungus exclusively grows on the packing, which provides a considerable advantage for astin C recovery and purification. C. asteris metabolism is different according to the culture conditions in terms of substrate consumption rate, cell growth, and astin C production. Immobilized-cell cultures yield a 30% increase of astin C production, associated with a 39% increase in biomass. The inoculum type as spores rather than hyphae, and a pre-inoculation washing procedure with sodium hydroxide, turns out to be beneficial both for astin C production and fungus development onto the support. Finally, the influence of culture parameters such as pH and medium composition on astin C production is evaluated. With optimized culture conditions, astin C yield is further improved reaching a five times higher final specific yield compared to the value reported with astin C extraction from A. tataricus (0.89 mg g-1 and 0.16 mg g-1 respectively).


Assuntos
Ascomicetos/metabolismo , Meios de Cultura/química , Microbiologia Industrial/métodos , Peptídeos Cíclicos/biossíntese , Ascomicetos/citologia , Ascomicetos/crescimento & desenvolvimento , Reatores Biológicos , Células Imobilizadas , Endófitos/metabolismo , Microbiologia Industrial/instrumentação , Plâncton , Aço Inoxidável
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