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1.
Bioprocess Biosyst Eng ; 47(1): 145-157, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38103079

RESUMO

Global environmental concerns drive research toward the development of new eco-friendly compounds to replace pollutant chemicals. This study focuses on optimizing the production of trehalose lipids (TLs), which are glycolipid biosurfactants (BS) with various applications like antimicrobial or surface tension reduction. New microorganism sources, growth conditions, medium composition, purification conditions, and physicochemical properties of TLs are studied. Addressing a microscale approach, TLs production was successfully achieved using Rhodotorula sp. and Rhodococcus erythropolis to compare, with different media compositions including glucose-based and salt media supplemented with glycerol, glucose, n-hexadecane, n-dodecane. Liquid-liquid extraction using ethyl acetate and methanol was employed for compound extraction, followed by characterization using analytical methods such as Thin layer chromatography (TLC), High performance liquid chromatography (HPLC), and UHPLC. The produced TLs exhibited a minimum surface tension of 47 mN/m and a critical micellar concentration of 4.4 mg/mL. This study also identified Rhodotorula sp. as a new sustainable producer of TLs with improved productivity.


Assuntos
Rhodotorula , Trealose , Glicolipídeos , Micelas , Glucose , Tensoativos/química
2.
Bioprocess Biosyst Eng ; 39(12): 1825-1837, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27538771

RESUMO

Sophorolipids (SLs) were produced by Starmerella bombicola. The separation and purification of SLs are a complex process, since they are produced as a mixture of compounds with few structural differences. Solvent extraction is commonly used in downstream processing. In this work, an environmental friendly approach was developed for SLs recovery and purification, based on neutral polymeric sorbents, Amberlite XAD16NTM, XAD18TM, and XAD1600NTM. In batch microassays, key parameters of sorption/desorption process (e.g., contact time, temperature, sorbents, and SLs concentrations) were optimized for separation of acidic and lactonic SLs. Sorption equilibrium was reached after 2-3 h, for all the sorbents tested. Among them XAD1600NTM showed a higher sorption capacity (q max 230 mg g-1), a higher removal (≈100 %) of acidic and lactonic SLs [1 and 2.5 % (w/v)], and the best selectivity. Methanol, ethanol, and acetone were suitable for SLs elution. A selective desorption of SLs was attained with acetonitrile aqueous solutions (v/v): (1) 25 % led to 88.3 % of acidic SLs and (2) 55 % followed by methanol solution (100 %) led to 93.2 % of purified lactonic SLs. This achievement was particularly important regarding SLs potential therapeutic applications, since acidic and lactonic SLs show different biologic activities. In fact, acid SLs show higher virucidal and pro-inflammatory cytokine activity, while lactonic SLs show stronger spermicidal and anti-cancer activity.


Assuntos
Antineoplásicos , Meios de Cultura/química , Lipídeos , Saccharomycetales/crescimento & desenvolvimento , Espermicidas , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Lipídeos/biossíntese , Lipídeos/química , Lipídeos/isolamento & purificação , Espermicidas/química , Espermicidas/isolamento & purificação
3.
J Mol Recognit ; 28(3): 155-65, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25647712

RESUMO

Sophorolipids (SLs) are glycolipid biosurfactants, produced as a mixture of several compounds by some nonpathogenic yeast. In the current study, separation of individual SLs from mixtures with further evaluation of their surface properties and biologic activity on MDA-MB-321 breast cancer cell line were investigated. SLs were biosynthesized by Starmerella bombicola in a culture media supplemented with borage oil. A reverse-phase flash chromatography method with an automated system coupled with a prepacked cartridge was used to separate and purify the main SLs. Compositional analysis of SLs was performed by high-performance liquid chromatography with electrospray ionization mass spectrometry and tandem mass spectrometry. The following diacetylated lactonic SLs were isolated and purified: C18:0, C18:1, C18:2, and C18:3. The critical micelle concentration (CMC) and surface tension at CMC (γCMC ) of the purified SLs showed an increase with the number of double bonds. High cytotoxic effect against MDA-MB-231 cells was observed with C18:0 and C18:1 lactonic SLs. The cytotoxic effects of C18:3 lactonic SL on cancerous cells were for the first time studied. This cytotoxic effect was considerably higher than the promoted by acidic SLs; however, it induced a lower effect than the previously mentioned SLs, C18:0 and C18:1. To our knowledge, for the first time, C18:1 lactonic SL, in selected concentrations, proved to be able to inhibit MDA-MB-231 cell migration without compromising cell viability and to increase intracellular reactive oxygen species.


Assuntos
Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Glicolipídeos/biossíntese , Glicolipídeos/farmacologia , Saccharomycetales/fisiologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Cromatografia Líquida/métodos , Meios de Cultura/química , Feminino , Humanos , Óleos de Plantas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Ácido gama-Linolênico/farmacologia
4.
Tissue Eng Part B Rev ; 30(4): 436-447, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38149607

RESUMO

Cardiovascular diseases, considered the deadliest worldwide by the World Health Organization (WHO), lack effective therapies for regenerating cardiomyocytes. With their self-renewal and pluripotency capabilities, stem cell therapies are increasingly used in precision medicine. Induced pluripotent stem cells (iPSCs) are a promising alternative to embryonic stem cells. Good Manufacturing Practice (GMP) principles are not yet adapted for large-scale production of iPSCs. Additionally, the quality risk for iPSC products may not always be possible to eliminate, potentially jeopardizing the health of patients. This review aims to identify critical quality attributes (CQAs) for iPSC-derived cardiomyocytes (iPSC-CMs) for the development of cardiovascular therapy to ensure compliance with regulations and safety for patients. To attain these goals, the literature review was conducted with articles related to iPSCs and iPSC-CM therapies, legislation, and regulatory guidelines of the European Medicines Agency (EMA), Food and Drug Administration (FDA), and Pharmaceuticals and Medical Devices Agency (PMDA). In conclusion, additional regulations and guidelines are needed to monitor differentiation, maturation, and tumorigenicity. GMP-compliant cell banks and fast-track approval systems may increase accessibility for patients.


Assuntos
Células-Tronco Pluripotentes Induzidas , Miócitos Cardíacos , Humanos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Diferenciação Celular , Animais , Pesquisa Translacional Biomédica
5.
Int J Biol Macromol ; 270(Pt 1): 132379, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38754680

RESUMO

Hydrogels based on natural polysaccharides have demonstrated efficacy in epithelial recovery from cutaneous burn wounds. Here, we prepared a double-network hydrogel consisting of galactomannan (from Cassia grandis seeds) and κ-carrageenan (commercially sourced), cross-linked with CaCl2, as a matrix for immobilizing lactoferrin and/or Cramoll, aiming at its applicability as dressings for second-degree burn wounds. The formulations obtained [H - hydrogel, HL - hydrogel + lactoferrin, HC - hydrogel + Cramoll and HLC - hydrogel + lactoferrin + Cramoll] were analyzed rheologically as well as in terms of their stability (pH, color, microbial contamination) for 90 days. The burn was created with an aluminum bar (97 ± 3 °C) in the dorsal region of Wistar rats and subsequently treated with hydrogels (H, HL, HC, HLC) and control saline solution (S). The burn was monitored for 3, 7 and 14 days to evaluate the efficacy of the hydrogels in promoting wound healing. The hydrogels did not reveal significant pH or microbiological changes; there was an increase in brightness and a reduction in opacity for H. The rheological analysis confirmed the gel-like viscoelastic signature of the systems without substantial modification of the basic rheological characteristics, however HLC proved to be more rigid, due to rheological synergy when combining protein biomolecules. Macroscopic analyses confirmed centripetal healing with wound contraction: S < H < HC < HL < HLC. Histopathological analyses showed that hydrogel-treated groups reduced inflammation, tissue necrosis and fibrosis, while promoting re-epithelialization with focal acanthosis, especially in HLC due to a positive synergistic effect, indicating its potential as a promising therapy in the repair of burns.


Assuntos
Queimaduras , Carragenina , Galactose , Hidrogéis , Mananas , Ratos Wistar , Cicatrização , Hidrogéis/química , Mananas/química , Mananas/farmacologia , Animais , Queimaduras/terapia , Queimaduras/tratamento farmacológico , Carragenina/química , Cicatrização/efeitos dos fármacos , Ratos , Galactose/análogos & derivados , Galactose/química , Masculino , Lactoferrina/química , Reologia
6.
Appl Microbiol Biotechnol ; 97(5): 1875-87, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23064480

RESUMO

Microtiter plates were used as minireactors to study Starmerella bombicola growth and sophorolipid (SL) production. Compositional analysis of SL mixtures by liquid chromatography with electrospray ionization tandem mass spectrometry showed similar results on SLs produced using the laboratory scale (shake flask) and the microscale (24-well microtiter plates (MTP)) approach. MTP suitability on SL production was proven, being this approach, especially advantageous on SL screening. Several hydrophilic carbon sources, hydrophobic co-substrates and nitrogen sources were supplied to culture media, and their influence on SL production was evaluated. The selection of specific hydrophobic co-substrate and nitrogen sources influenced the ratio acidic/lactonic SLs. In fact, it was observed that the production of acidic C18:1 diacetylated hydroxy fatty acid SLs was favoured when culture media was supplied with avocado, argan, sweet almond and jojoba oil or when NaNO(3) was supplied instead of urea. This last case was observed after 144 h of cultivation. A new SL, lactonic C18:3 hydroxy fatty acid diacetylated SL, was detected when borage and onagra oils were used individually as co-substrates. Overall results indicated the potential of the selective production of different and new sophorolipids by Starmerella bombicola based on the selection of carbon and nitrogen sources to culture media.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Meios de Cultura/química , Glicolipídeos/metabolismo , Carbono/metabolismo , Cromatografia Líquida , Ensaios de Triagem em Larga Escala/métodos , Nitrogênio/metabolismo , Óleos de Plantas/metabolismo , Espectrometria de Massas em Tandem
7.
Plants (Basel) ; 12(7)2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37050137

RESUMO

The cactus, Opuntia ficus-indica (L.) Mill. (OFI) belongs to the Cactaceae family, which contains about 130 genera and nearly 1600 species. This review aims to evaluate this plant from several perspectives, namely, botanic, physicochemical, nutritional, and medicinal properties, as well as agro-industrial use. The botanical aspects and morphological characteristics of OFI enable genetic variability, ecological adaptation, and broad geographic distribution. Due to its physicochemical and nutritional composition, it has several medicinal properties appropriate (or suitable) for several industries, such as pharmaceutical, food, and cosmetics. Its fruit, the prickly pear (PP), has potential agro-industrial expansion through the application of different conservation and transformation methods, making it possible to obtain a variety of products. The PP is a source of several nutrients and is an effective system to produce varied foods, which have several advantages from a nutritional, sensory, economic, and shelf-life point of view.

8.
Gels ; 9(12)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38131954

RESUMO

Nanofibrous materials present interesting characteristics, such as higher area/mass ratio and reactivity. These properties have been exploited in different applications, such as drug-controlled release and site-specific targeting of biomolecules for several disease treatments, including cancer. The main goal of this study was to develop magnetized nanofiber systems of lysozyme (Lys) for biological applications. The system envisaged electrospun polyvinyl alcohol (PVA) and PVA/chitosan (CS) nanofibers, loaded with Lys, crosslinked with boronic acids [phenylboronic acid (PBA), including 2-acetylphenylboronic acid (aPBA), 2-formylphenylboronic (fPBA), or bortezomib (BTZ)] and functionalized with magnetic nanobeads (IONPs), which was successfully built and tested using a microscale approach. Evaluation of the morphology of nanofibers, obtained by electrospinning, was carried out using SEM. The biological activities of the Lys-loaded PVA/CS (90:10 and 70:30) nanofibers were evaluated using the Micrococcus lysodeikticus method. To evaluate the success of the encapsulation process, the ratio of adsorbed Lys on the nanofibers, Lys activity, and in vitro Lys release were determined in buffer solution at pH values mimicking the environment of cancer cells. The viability of Caco-2 cancer cells was evaluated after being in contact with electrospun PVA + Lys and PVA/CS + Lys nanofibers, with or without boronic acid functionalation, and all were magnetized with IONPs.

9.
Int J Biol Macromol ; 251: 126213, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37567532

RESUMO

The epithelium recovery of skin-burned wounds has been currently achieved by several therapies, for example, hydrogel-based dressings and photobiomodulation therapy (PBMT). Thus, this work aimed to evaluate the healing activity of Cassia grandis seeds' galactomannan gel, associated or not with PBMT, in second-degree burns. Sixty male Wistar rats were assigned to four groups: Control (CG), Gel (GG), Laser/PBMT (LG), and Laser+Gel (GLG). Burns were made with an aluminum bar (90 °C), and submitted to clinical observations diary and area measurements at specific days. Microscopic analysis was based on histological criteria. The results showed that GG, LG, and GLG had a higher contraction rate (p < 0.05) than CG on the 14th experimental day, not differing from each other (∼95 %). At 21 days, all groups showed complete contraction (p > 0.05). Considering the histological results, LG and GLG showed excellent pro-wound healing properties after 14 days; at 21 days, all groups showed wound recovery compared to previous days. In view of the macroscopic and microscopic observations, the isolated treatments (Gel or Laser) effectively accelerated healing; however, the association (Laser+Gel) promoted re-epithelialization and stromal remodeling with better evolution of epithelium recovery due to the positive synergistic effect, thus emerging as a promising therapeutic alternative in the repair of burns.

10.
J Mol Recognit ; 25(11): 595-603, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23108619

RESUMO

Hesperidin (hesperitin-7-O-rutinoside) and hesperitin (hesperitin-7-O-glucoside) show anti-inflammatory, antimicrobial, antioxidant, and anticarcinogenic effects and prevent bone loss. However, hesperidin has a low bioavailability compared to hesperitin due to the rutinoside moiety attached to the flavonoid. The removal of the rhamnose group to yield the corresponding flavonoid glucoside (hesperetin-7-glucoside) improved the bioavailability of the aglycone, hesperetin, in humans. In line with these assumptions, the aim of this work was the enzymatic production of hesperitin from hesperidin with hesperidinase. Despite the low hesperidin solubility in the reaction medium, the enzymatic bioconversion was carried with hesperidin soluble at lower concentrations (≤0.05 mg ml(-1)) and insoluble for high concentrations (>0.1-50 mg ml(-1)). A twofold increase in maximum reaction rates overtook the expected values, pointing to the enzyme ability to degrade insoluble hesperidin. To improve the bioprocess, hesperidinase was tested soluble and immobilized in calcium alginate (2%), k-carrageenan (2%), and chitosan (2%) beads. The immobilization was carried out by adsorption and encapsulation. Chitosan was cross-linked with glutaraldehyde (1% and 2%) and sodium sulfate (13.5% and 15%) in acetate buffer (0.02 M, pH 4.0). The relation between bioprocessing conditions and hesperidinase stability was studied. A residual activity of 193% was obtained with immobilized hesperidinase compared to the soluble form. A half-life of 770 min was attained with hesperidinase encapsulated in calcium alginate beads. The results presented in this work highlight the potential of hesperidinase encapsulation towards hesperitin production with insoluble substrate. To our knowledge, this work presents for the first time the potential of hesperidinase encapsulation on hydrogels for hesperitin production. This is an important achievement for pharmaceutical and nutraceutical applications of hesperitin because this compound presents a higher bioavailability compared to hesperidin.


Assuntos
Enzimas Imobilizadas/química , Proteínas Fúngicas/química , Glicosídeo Hidrolases/química , Hesperidina/química , Adsorção , Alginatos/química , Aspergillus niger/química , Aspergillus niger/enzimologia , Disponibilidade Biológica , Soluções Tampão , Carragenina/química , Quitosana/química , Reagentes de Ligações Cruzadas , Composição de Medicamentos , Ácido Glucurônico/química , Glutaral , Meia-Vida , Ácidos Hexurônicos/química , Hidrogéis , Cinética
11.
J Mol Recognit ; 25(11): 580-94, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23108618

RESUMO

Polyvinyl alcohol (PVA) is a water-soluble, biocompatible and biodegradable synthetic polymer whose application in the immobilization of biological agents for use in biocatalysis has shown promising results. This study aimed to investigate and optimize the immobilization of naringinase from Penicillium decumbens in PVA networks, targeting for the hydrolysis of naringin. Variables such as the most suitable cross-linker, catalyst, inorganic salt, co-solvents and solidification process were identified as key issues for PVA-based methods to form lens-shaped particles, while retaining high enzyme activity and stability. Major improvements were established for better and more reproducible immobilization conditions, namely, by designing a new immobilization apparatus to produce uniform lens-shaped particles. The common problems of PVA-based entrapment were significantly mitigated, through the use of selected cross-linker, glutaraldehyde (GA), and co-solvent, dimethyl sulfoxide (DMSO), which decreased the toxicity of the immobilization process and allowed the control of membrane porosity, respectively. The relevance of DMSO and GA and their interaction and effect on the swelling ratio, encapsulation efficiency and residual activity of PVA biocatalysts were established. The immobilization of naringinase in PVA under a DMSO concentration of 60%, cross-linked with 1% GA, and particle lens size of 3.5-4.0 mm, width of 100-300 µm and average particle volume of 12.5 ± 0.92 µL, allowed an encapsulation efficiency of 98.6% and an average residual activity of 87% ± 3.6%. The kinetic characterization of the immobilized naringinase showed no changes in pH profile, whereas hydrolytic activity increased up to 60 °C. Immobilization in PVA/DMSO/GA lens-shaped particles enhanced the storage stability of naringinase. Moreover, these naringinase bio-immobilizates retained a conversion rate higher than 78% after 23 runs.


Assuntos
Dimetil Sulfóxido/química , Enzimas Imobilizadas/química , Proteínas Fúngicas/química , Complexos Multienzimáticos/química , Penicillium/enzimologia , Álcool de Polivinil/química , beta-Glucosidase/química , Biocatálise , Reagentes de Ligações Cruzadas , Composição de Medicamentos , Estabilidade Enzimática , Flavanonas/química , Glutaral , Cinética , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Penicillium/química , Porosidade , Solubilidade , Temperatura , Água
12.
J Mol Recognit ; 25(11): 630-40, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23108623

RESUMO

Rhodotorula bogoriensis is known as the producer of longer chain acidic sophorolipids (SLs) with a unique hydroxylation position where the sophorose unit is linked to the 13-hydroxydocosanoic acid. The influence of initial inoculum concentration, hydrophilic and hydrophobic carbon, and nitrogen sources on R. bogoriensis growth and SL production was evaluated to obtain a selective SL production. Experiments took place in microtiter plates, used as minireactors, after the verification of its suitability compared with shake flasks. The common structure of SLs is the 13-[2'-O-ß-d-glucopyranosyl-ß-d-glucopyranosyloxy]-docosanoic acid SL. The analysis of the fermentation media using high-performance liquid chromatography with evaporative light scattering detector showed the production of four main SLs, respectively, in the following forms: (i) deacetylated (peak A) (C22:0 SL), (ii) 6″monoacetylated (peak B) (C22:0-6″Ac SL), (iii) 6'monoacetylated (peak C) (C22:0-6'Ac SL), and (iv) 6',6″ diacetylated (peak D) (C22:0-6',6″Ac SL). The identification of compounds in SL mixtures was performed by liquid chromatography with electrospray ionization mass spectrometry analysis, and no differences were observed. Besides the four compounds detected using high-performance liquid chromatography with evaporative light scattering detector chromatograms, three other SLs was identified, corresponding to mono- and diacetylated C24:0 hydroxy fatty acid SLs. To our knowledge, this work presents for the first time the production and identification of C24:0 SLs. A longer hydrophobic tail on SLs had an important role in the improvement of surface active properties. The selection of a specific time for fermentation end and the use of different carbon (e.g. glucose, fructose, mannose, lactose, galactose, xylose) and nitrogen (e.g. peptone, (NH(4))(2)SO(4) and NaNO(3)) sources led to a selective production of de-, mono-, and diacetylated SLs by R. bogoriensis.


Assuntos
Carbono/metabolismo , Ácidos Graxos/química , Glucanos/química , Glicolipídeos/biossíntese , Nitrogênio/metabolismo , Rhodotorula/metabolismo , Cromatografia Líquida de Alta Pressão , Meios de Cultura , Ácidos Graxos/metabolismo , Fermentação , Glucanos/metabolismo , Glicolipídeos/química , Glicolipídeos/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray
13.
Appl Microbiol Biotechnol ; 90(6): 1883-95, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21544655

RESUMO

Naringinase, an enzyme complex, is commercially attractive due to its potential usefulness in pharmaceutical and food industries. It is of particular interest in the biotransformation of steroids, antibiotics, and mainly of glycosides hydrolysis. Moreover, it can be used in citrus juices debittering and wine industries. Naringinase expresses activity on α-L-rhamnosidase and ß-D-glucosidase. Many natural glycosides, including naringin, rutin, quercitrin, hesperidin, diosgene, and ter-phenyl glycosides, containing terminal α-rhamnose and ß-glucose can act as substrates of naringinase. The sources, production, activity, biochemical properties, and substrate specificity of naringinase are reviewed, along with a description of the enzymatic deglycosylation systems and applications, concluding with the identification of areas which need further extensive studies.


Assuntos
Complexos Multienzimáticos/metabolismo , Complexos Multiproteicos/metabolismo , beta-Glucosidase/metabolismo , Biotecnologia/métodos , Tecnologia de Alimentos/métodos , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/isolamento & purificação , Complexos Multiproteicos/genética , Complexos Multiproteicos/isolamento & purificação , Especificidade por Substrato , Tecnologia Farmacêutica/métodos , beta-Glucosidase/genética , beta-Glucosidase/isolamento & purificação
14.
J Hazard Mater ; 412: 125323, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33951876

RESUMO

In the present study, highly pure rhamnolipids (RLs) was produced using biocatalysts immobilized on amino-functionalized chitosan coated magnetic nanoparticles. Upon immobilizing naringinase and Candida antarctica lipase B (CaLB) under the optimized conditions, an enhanced operational stability with biocatalytic loads of 935 ± 2.4 U/g (naringinase) and 825 ± 4.1 U/g (CaLB) were achieved. Subsequently, the immobilized biocatalysts were utilized sequentially in a two-step RLs synthesis process. The key parameters involved in RLs production were optimized using artificial neural network (ANN) coupled genetic algorithm (GA) and were compared with composite central design (CCD). On validating the efficiency of both models, mean square errors of 1.58% (CCD) and 1.04% (ANN) were obtained. Optimization of parameters by ANN-GA resulted in 1.2-fold increase in experimental RLs yield (80.53%), which was 1.05-fold higher when compared to CCD model. Further, to establish the efficiency of RLs as a bioremediation agent, it was utilized as washing agent. It was observed that at a soil to RLs volume of 1:05, RLs concentration of 0.4 mg/mL, a 95.35 ± 1.33% removal of Total Petroleum Hydrocarbons (TPHs) was obtained at 35 â„ƒ and 160 rpm in 75 min. Thus, this strategy provides an efficient biocatalytic toolbox for RLs synthesis, which can be effectively used as a bioremediation agent.


Assuntos
Enzimas Imobilizadas , Proteínas Fúngicas , Basidiomycota , Biodegradação Ambiental , Glicolipídeos , Fenômenos Magnéticos
15.
Bioresour Technol ; 273: 326-334, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30448685

RESUMO

The newly isolated oleaginous yeast, Rhodotorula babjevae Y-SL7, was shown to accumulate high intracellular content of microbial oil (mainly triacylglycerols) and to secret, under the same culture conditions, an atypical glycolipid. This unusual behavior was induced when the strain was subjected to nitrogen limitation and high amount of carbon. A series of analytical methods was adopted in order to structurally characterize the secreted glycolipid. The latter consists of a mixture of 9 molecules formed by a polyol head group, bound through the carboxyl end of an acetylated 3-hydroxy fatty acid with C18 or C16 chain length. In addition of their physicochemical properties such as emulsifying activity on hydrophobic substrates, Y-SL7 glycolipids have shown a therapeutically promising cytotoxic effect against different cancer cell lines. In fact, Y-SL7 strain can be used for the production of triacylglycerols as energetic molecules and for the secretion of a biosurfactant of therapeutic and environmental interest.


Assuntos
Glicolipídeos/metabolismo , Rhodotorula/metabolismo , Triglicerídeos/biossíntese , Biotecnologia , Ácidos Graxos/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Nitrogênio/metabolismo
16.
Bioresour Technol ; 249: 704-712, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29091856

RESUMO

The goal of this work was the development of magnetic cross link enzyme aggregates (mCLEAs) of rhamnopyranosidase (Rhmnase), prepared by chemical cross-linking with functionalized magnetite nanoparticles for glycompounds biosynthesis in microbioreactors (specially design 24-well microplate and mini-packed bed). Rhamnopyranosidase (EC number 3.2.1.40) present high potential in glycocompounds production, with applications in food and pharmaceutical industries. The influence of precipitants, cross-linkers, temperature and time on (m)CLEAs@Rhmnase development were optimized. Biocatalyst activity was accessed in the hydrolysis of 4',5,7-trihydroxyflavanone-7-rhamnoglucoside and kinetic constants in the deglycosylation reaction were evaluated. Rhmnase operational stability was enhanced in mCLEAs, retaining almost 90% initial activity after 7 cycles of 24 h each. In a mini-packed bed bioreactor a maximum volumetric productivity of 140 µmol/L.h was attained. In this bioreactor the operational stability of mCLEAs@Rhmnase were evaluated at a flow rate of 5 mL/h during 5 days and a residual activity of 95% was observed.


Assuntos
Reatores Biológicos , Nanopartículas de Magnetita , Reagentes de Ligações Cruzadas , Estabilidade Enzimática , Enzimas Imobilizadas , Hidrólise , Magnetismo
17.
Int J Biol Macromol ; 95: 268-272, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27851931

RESUMO

We have evaluated the effect of POLI-CHI hydrogel based on policaju (POLI) from cashew tree (Anacardium occidentale L.) gum and chitosan (CHI), associated or not with Low level laser therapy (LLLT), in wound healing. Sixty male Wistar rats were assigned into four groups: POLI-CHI hydrogel (H); LLLT (L); POLI-CHI with LLLT (HL) and saline control (C). Macroscopic evaluations were carried out using clinical observations and area measurements, as well as microscopic analysis by histological criteria. H and HL presented more esthetical scar tissue and larger wound contraction compared to C. Histopathological analyzes showed: stronger presence of fibrin-leukocyte crust in L and HL at day 3; stronger collagen presence in H, L and HL; weak presence of focal necrosis at 7 and 14days in H; weak neutrophilic exudate in H, L and HL; regression of the vascular neoformation at 7days in H, and modulation of the same in L and HL. These results demonstrated that POLI-CHI contributed to more efficient healing process and modulation of the inflammation; furthermore, the combined use with LLLT subtle potentiated this process.


Assuntos
Quitosana/química , Quitosana/farmacologia , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Terapia com Luz de Baixa Intensidade , Cicatrização/efeitos dos fármacos , Cicatrização/efeitos da radiação , Anacardium/química , Animais , Terapia Combinada , Masculino , Ratos , Ratos Wistar
18.
Int J Biol Macromol ; 102: 749-757, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28433769

RESUMO

Galactomannan films from Cassia grandis seeds, associated or not with Cramoll 1,4, were used on topical wounds of rats for the evaluation of the healing process during 14days. All of the films were evaluated by cytotoxic assay, FTIR and lectin hemagglutinating activity (HA). Forty-five male rats were submitted to aseptic dermal wounds (Ø=0.8cm) and divided in groups (n=15): control, test 1, and test 2, treated respectively with saline, galactomannan film and film with immobilized Cramoll 1,4. Macroscopic evaluations were performed by clinical observations and area measurements, and microscopic analysis by histological criteria. Epithelial cell proliferation and differentiation was immunohistochemically assessed using CK14 and PCNA. The presence of CO peaks in the FTIR spectrum confirmed the immobilization of Cramoll 1,4 in the film, while the residual HA confirmed the stability of the lectin after immobilization with 90.94% of the initial HA. The films presented non-cytotoxicity and cell viability exceeding 80%. All of the animals presented re-epithelization around 10days, furthermore test 2 group showed a diffuse response at the stromal tissue and the basal layer associated with wounds completely closed with 11days of experiment. The results suggest a promising use of the films as topical wound curatives.


Assuntos
Cassia/química , Mananas/química , Mananas/farmacologia , Lectinas de Plantas/química , Sementes/química , Cicatrização/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Galactose/análogos & derivados , Masculino , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos
19.
BMC Neurol ; 6: 24, 2006 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-16824219

RESUMO

BACKGROUND: Pathological brain iron deposition has been implicated as a source of neurotoxic reactive oxygen species in Alzheimer (AD) and Parkinson diseases (PD). Iron metabolism is associated with the gene hemochromatosis (HFE Human genome nomenclature committee ID:4886), and mutations in HFE are a cause of the iron mismetabolism disease, hemochromatosis. Several reports have tested the association of HFE variants with neurodegenerative diseases, such as AD and PD with conflicting results. METHODS: Genotypes were analysed for the two most common variants of HFE in a series of 130 AD, 55 Mild Cognitive Impairment (MCI) and 132 PD patients. Additionally, a series of 115 healthy age-matched controls was also screened. RESULTS: A statistically significant association was found in the PD group when compared to controls, showing that the presence of the C282Y variant allele may confer higher risk for developing the disease. CONCLUSION: Taken together these results suggest that the common variants in HFE may be a risk factor for PD, but not for AD in the Portuguese population.


Assuntos
Doença de Alzheimer/genética , Transtornos Cognitivos/genética , Predisposição Genética para Doença/genética , Antígenos de Histocompatibilidade Classe I/genética , Distúrbios do Metabolismo do Ferro/genética , Proteínas de Membrana/genética , Doença de Parkinson/genética , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/fisiopatologia , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/fisiopatologia , Estudos de Coortes , Comorbidade , Análise Mutacional de DNA , Feminino , Frequência do Gene/genética , Testes Genéticos , Variação Genética/genética , Genótipo , Proteína da Hemocromatose , Humanos , Ferro/metabolismo , Distúrbios do Metabolismo do Ferro/epidemiologia , Distúrbios do Metabolismo do Ferro/fisiopatologia , Masculino , Pessoa de Meia-Idade , Mutação/genética , Doença de Parkinson/epidemiologia , Doença de Parkinson/fisiopatologia , Portugal/epidemiologia , Tamanho da Amostra , Distribuição por Sexo
20.
Neurobiol Aging ; 41: 200.e1-200.e5, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27021778

RESUMO

We and others have reported heterozygous progranulin mutations as an important cause of frontotemporal lobar degeneration (FTLD). It has been identified a complete progranulin deficiency because of a homozygous mutation in a sibling pair with neuronal ceroid lipofuscinosis (NCL). Here, we describe the first case of NCL caused by a homozygous progranulin mutation segregating in a family with neuropathological confirmed FTLD. In this FTLD-NCL family, we detail the clinical phenotype, neuropsychological evaluation and imaging data of our proband harboring a homozygous mutation, c.900_901dupGT, with serum progranulin level (<6 ng/mL). Symptoms included rapidly progressive visual deficit, slightly dysarthria, and cerebellar ataxia. The electroretinogram confirmed a severe attenuation of rod and cone responses compatible with retinal dystrophy diagnosis and magnetic resonance imaging showed severe global cerebellar atrophy. In contrast, heterozygous relatives presented behavioral variant of frontotemporal dementia (FTD) and some also developed extrapyramidal features compatible with corticobasal syndrome. Our findings suggest the importance of assessing serum progranulin levels in suspected recessive adult-onset NCL cases. Overall, a more holistic neurologic intervention is needed to guarantee a proper genetic counseling in cases like the present family where two distinct phenotypes are generated according to the individuals' mutation state.


Assuntos
Degeneração Lobar Frontotemporal/epidemiologia , Degeneração Lobar Frontotemporal/genética , Estudos de Associação Genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Mutação , Lipofuscinoses Ceroides Neuronais/epidemiologia , Lipofuscinoses Ceroides Neuronais/genética , Biomarcadores/sangue , Comorbidade , Degeneração Lobar Frontotemporal/diagnóstico , Heterozigoto , Homozigoto , Lipofuscinoses Ceroides Neuronais/diagnóstico , Fenótipo , Portugal , Progranulinas
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