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1.
Carbohydr Polym ; 343: 122495, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39174106

RESUMO

Bacterial cellulose (BC) is gathering increased attention due to its remarkable physico-chemical features. The high biocompatibility, hydrophilicity, and mechanical and thermal stability endorse BC as a suitable candidate for biomedical applications. Nonetheless, exploiting BC for tissue regeneration demands three-dimensional, intricately shaped implants, a highly ambitious endeavor. This challenge is addressed here by growing BC within a sacrificial viscoelastic medium consisting of an agarose gel cast inside polydimethylsiloxane (PDMS) molds imprinted with the features of the desired implant. BC produced with and without agarose has been compared through SEM, TGA, FTIR, and XRD, probing the mild impact of the agarose on the BC properties. As a first proof of concept, a PDMS mold shaped as a doll's ear was used to produce a BC perfect replica, even for the smallest features. The second trial comprised a doll face imprinted on a PDMS mold. In that case, the BC production included consecutive deactivation and activation of the aerial oxygen stream. The resulting BC face clone fitted perfectly and conformally with the template doll face, while its rheological properties were comparable to those of collagen. This streamlining concept conveys to the biosynthesized nanocelluloses broader opportunities for more advanced prosthetics and soft tissue engineering uses.


Assuntos
Celulose , Dimetilpolisiloxanos , Oxigênio , Sefarose , Celulose/química , Sefarose/química , Oxigênio/química , Dimetilpolisiloxanos/química , Reologia , Engenharia Tecidual/métodos , Materiais Biocompatíveis/química , Alicerces Teciduais/química
2.
Environ Res ; 257: 119231, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38797468

RESUMO

The persistent water treatment and separation challenge necessitates innovative and sustainable advances to tackle conventional and emerging contaminants in the aquatic environment effectively. Therefore, a unique three-dimensional (3D) network composite film (BNC-KC) comprised of bacterial nanocellulose (BNC) incorporated nano-kaolinite clay particles (KC) was successfully synthesized via an in-situ approach. The microscopic characterization of BNC-KC revealed an effective integration of KC within the 3D matrix of BNC. The investigated mechanical properties of BNC-KC demonstrated a better performance compared to BNC. Thereafter, the sorption performance of BNC-KC films towards basic blue 9 dye (Bb9) and norfloxacin (NFX) antibiotic from water was investigated. The maximum sorption capacities of BNC-KC for Bb9 and NFX were 127.64 and 101.68 mg/g, respectively. Mechanistic studies showed that electrostatic interactions, multi-layered sorption, and 3D structure are pivotal in the NFX/Bb9 sorption process. The intricate architecture of BNC-KC effectively traps molecules within the interlayer spaces, significantly increasing sorption efficiency. The distinctive structural configuration of BNC-KC films effectively addressed the challenges of post-water treatment separation while concurrently mitigating waste generation. The environmental evaluation, engineering, and economic feasibility of BNC-KC are also discussed. The cost estimation assessment of BNC-KC revealed the potential to remove NFX and Bb9 from water at an economically viable cost.


Assuntos
Celulose , Poluentes Químicos da Água , Celulose/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Adsorção , Argila/química , Purificação da Água/métodos , Norfloxacino/química , Antibacterianos/química , Silicatos de Alumínio/química , Corantes/química , Corantes/isolamento & purificação
3.
Sci Rep ; 12(1): 7012, 2022 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-35488046

RESUMO

In the recent years, huge efforts have been conducted to conceive a cost-effective production process of the bacterial nanocellulose (BNC), thanks to its marvelous properties and broadening applications. Herein, we unveiled the impact of gamma irradiation on the BNC yield by a novel bacterial strain Komagataeibacter hansenii KO28 which was exposed to different irradiation doses via a designed scheme, where the productivity and the structural properties of the BNC were inspected. After incubation for 240 h, the highest BNC yield was perceived from the culture treated twice with 0.5 kGy, recording about 475% higher than the control culture. Furthermore, almost 92% of its BNC yield emerged in the first six days. The physicochemical characteristics of the BNCs were investigated adopting scanning electron microscope (SEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Fourier transform infrared (FTIR). Additionally, the water holding capacity, water release rate, surface area (BET), and mechanical properties were configured for the BNC generated from the control and the irradiated cultures. As a whole, there were no significant variations in the properties of the BNC produced by the irradiated cultures versus the control, proposing the strain irradiation as a valuable, facile, and cheap route to augment the BNC yield.


Assuntos
Celulose , Água , Celulose/química , Raios gama , Difração de Raios X
4.
Lett Appl Microbiol ; 72(4): 427-437, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33278032

RESUMO

Huperzine A (HupA) is an anti-Alzheimer's therapeutic and a dietary supplement for memory boosting that is extracted mainly from Huperziacae plants. Endophytes represent the upcoming refuge to protect the plant resource from distinction but their HupA yield is still far from commercialization. In this context, UV and gamma radiation mutagenesis of the newly isolated HupA-producing Alternaria brassicae AGF041 would be applied in this study for improving the endophytic HupA yield. Compared to non-irradiated cultures, UV (30-40 min, exposure) and γ (0·5 KGy, dose) irradiated cultures, each separately, showed a significant higher HupA yield (17·2 and 30·3%, respectively). While, application of a statistically optimized compound irradiation (0·70 KGy of γ treatment and 42·49 min of UV exposure, sequentially) via Response Surface Methodology (RSM) resulted in 53·1% production increase. Moreover, a stable selected mutant strain CM003 underwent batch cultivation using a 6·6 l bioreactor for the first time and was successful for scaling up the HupA production to 261·6 µg l-1 . Findings of this research are demonstrated to be valuable as the employed batch fermentation represents a successful starting step towards the promising endophytic HupA production at an industrial scale.


Assuntos
Alcaloides/metabolismo , Alternaria/genética , Alternaria/metabolismo , Reatores Biológicos/microbiologia , Inibidores da Colinesterase/metabolismo , Huperzia/metabolismo , Sesquiterpenos/metabolismo , Cromatografia Líquida de Alta Pressão , Endófitos/isolamento & purificação , Endófitos/metabolismo , Fermentação , Raios gama , Huperzia/microbiologia , Fármacos Neuroprotetores/metabolismo , Raios Ultravioleta
5.
Appl Radiat Isot ; 166: 109389, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32882652

RESUMO

Copper oxide nanoparticles (CuO NPs) are needed in various fields, especially in the biomedical field. CuO NPs was obtained from Aspergillus terreus filtrate. CuO NPs structure was confirmed by UV-Vis spectrophotometry, as well as Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). XRD offers the nanoparticles purity of CuO biosynthesis. CuO NPs are spherical when examined with TEM. The average size of CuO NPs from TEM was 15.75 ± 3.95 nm. New composite of P (AA-AN)-NPs CuO was synthesized by biotechnology and the induced γ-radiation. The distribution coefficient value (Kd) of 47Sc(III) as well as 47Ca(II) ions for the synthetic new composite was determined by batch technique. Radiochemical separation of 47Sc(III) from irradiated calcium target was studied using chromatographic column packed with the new composite material. The recovery yield of 78 ± 1.2% for 47Sc(III) was obtained using 1 M HCl. The quality control tests (chemical, radionuclide and radiochemical purities) of the eluted 47Sc confirmed that it's adequate for nuclear medicine applications.


Assuntos
Cobre/metabolismo , Nanopartículas Metálicas/química , Radioisótopos/isolamento & purificação , Escândio/isolamento & purificação , Aspergillus/metabolismo , Cobre/efeitos da radiação , Humanos , Nanopartículas Metálicas/efeitos da radiação , Nanopartículas Metálicas/ultraestrutura , Nanocompostos/química , Nanocompostos/efeitos da radiação , Nanocompostos/ultraestrutura , Medicina Nuclear , Tamanho da Partícula , Controle de Qualidade , Radioquímica , Radioisótopos/normas , Compostos Radiofarmacêuticos/isolamento & purificação , Compostos Radiofarmacêuticos/normas , Escândio/normas , Nanomedicina Teranóstica/métodos
6.
Appl Microbiol Biotechnol ; 103(14): 5867-5878, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31119352

RESUMO

Huperzine A (HupA) is a potent acetylcholinesterase (AChE) inhibitor of a great consideration as a prospective drug candidate for Alzheimer's disease treatment. Production of HupA by endophytes offers an alternative challenge to reduce the massive plant harvest needed to meet the increasing demand of HupA. In the current study, some endophytic fungal and actinobacterial isolates from the Chinese herb, Huperzia serrata, underwent liquid fermentation, alkaloid extraction, and screening for AChE inhibition and HupA production. Among these isolates, Alternaria brassicae AGF041 strain was the only positive strain for HupA production with the maximum AChE inhibition of 75.5%. Chromatographic analyses verified the identity of the produced HupA. The HupA production was efficiently maximized up to 42.89 µg/g of dry mycelia, after optimization of thirteen process parameters using multifactorial statistical approaches, Plackett-Burman and central composite designs. The statistical optimization resulted in a 40.8% increase in HupA production. This is the first report to isolate endophytic actinobacteria with anti-AChE activity from H. serrata, and to identify an endophytic fungus A. brassicae as a new promising start strain for a higher HupA yield.


Assuntos
Alcaloides/biossíntese , Alternaria/metabolismo , Inibidores da Colinesterase/metabolismo , Fermentação , Huperzia/microbiologia , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Micélio , Estudos Prospectivos , Sesquiterpenos
7.
Biotechnol Rep (Amst) ; 18: e00247, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29876299

RESUMO

Tellurium has attracted the attention of many researchers and manufacturers due to its unique properties. Through the current work, six fungal isolates have been screened for their ability to reduce potassium tellurite (K2TeO3) into elemental tellurium nanoparticles (TeNPs). The most promising fungal isolate was identified as Aspergillus welwitschiae and given the accession number (KY766958) based on molecular basis and has been used for biogenic (enzymatic) production of TeNPs. The produced TeNPs have been characterized using DLS, TEM and FTIR. Data showed that, the particle size is 60.80 d.nm with oval to spherical shape. The produced TeNPs have been evaluated for antimicrobial activity at 25 mg/ml. Data revealed antibacterial activity against E. coli and Staphylococcus aureus (MRSA). Evaluation of the effect of γ-irradiation on TeNPs production showed that, the productivity was improved at 1 kGy and suppressed gradually at higher doses.

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