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1.
Int J Biol Macromol ; 265(Pt 2): 130933, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38508554

RESUMO

Glucans, a polysaccharide naturally present in the yeast cell wall that can be obtained from side streams generated during the fermentation process, have gained increasing attention for their potential as a skin ingredient. Therefore, this study focused on the extraction method to isolate and purify water-insoluble glucans from two different Saccharomyces cerevisiae strains: an engineered strain obtained from spent yeast in an industrial fermentation process and a wild strain produced through lab-scale fermentation. Two water-insoluble extracts with a high glucose content (> 90 %) were achieved and further subjected to a chemical modification using carboxymethylation to improve their water solubility. All the glucans' extracts, water-insoluble and carboxymethylated, were structurally and chemically characterized, showing almost no differences between both yeast-type strains. To ensure their safety for skin application, a broad safety assessment was undertaken, and no cytotoxic effect, immunomodulatory capacity (IL-6 and IL-8 regulation), genotoxicity, skin sensitization, and impact on the skin microbiota were observed. These findings highlight the potential of glucans derived from spent yeast as a sustainable and safe ingredient for cosmetic and skincare formulations, contributing to the sustainability and circular economy.


Assuntos
Glucanos , Saccharomyces cerevisiae , Glucanos/química , Saccharomyces cerevisiae/química , Polissacarídeos/química , Água
2.
Bioresour Technol ; 397: 130470, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395236

RESUMO

Here, Baijiu distillers' grains (BDGs) were employed in biorefinery development to generate value-added co-products and bioethanol. Through ethyl acetate extraction at a 1:6 solid-liquid ratio for 10 h, significant results were achieved, including 100 % lactic acid and 92 % phenolics recovery. The remaining BDGs also achieved 99 % glucan recovery and 81 % glucan-to-glucose conversion. Simultaneous saccharification and fermentation of remaining BDGs at 30 % loading resulted in 78.5 g bioethanol/L with a yield of 94 %. The minimum selling price of bioethanol varies from $0.149-$0.836/kg, contingent on the co-product market prices. The biorefinery processing of one ton of BDGs caused a 60 % reduction in greenhouse gas emissions compared to that of the traditional production of 88 kg corn-lactic acid, 70 kg antioxidant phenolics, 234 kg soybean protein, and 225 kg corn-bioethanol, along with emissions from BDG landfilling. The biorefinery demonstrated a synergistic model of cost-effective bioethanol production and low-carbon emission BDGs treatment.


Assuntos
Meio Ambiente , Glucanos , Análise Custo-Benefício , Fermentação , Ácido Láctico
3.
Work ; 73(1): 181-187, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35912760

RESUMO

BACKGROUND: Sewage treatment plant workers (STPs) are exposed to gaseous pollutants (H2S) and bioaerosols and their health is at risk. OBJECTIVE: The aim of the study was to evaluate exposures to dust, 1,3 Beta D Glucans, endotoxins and gaseous pollutants in different process plants and to provide suitable recommendations. METHODS: Gaseous pollutants and bioaerosols (inhalable dust, 1,3 beta D-glucans and endotoxins) were evaluated in two sewage treatment plants (STPs) of Ahmedabad city, India. The concentration of H2S, CO, CH4 and Cl2 were monitored in two process areas of STPs using real-time gas detectors. The dust, 1,3 beta D-glucans and endotoxins were evaluated as per standard methods. RESULTS: The mean concentration of H2S exceeded the permissible exposure limit of 10 ppm, whereas the concentration of other gaseous pollutants (CO, Cl2 and CH4) were below the permissible exposure limits of Indian Factories Act, 1948. The inhalable dust concentration was also within the permissible exposure limit of 10 mg/m3 as per Indian Factories Act, 1948. CONCLUSIONS: Significant exposures to gaseous and bioaerosols were found in the work environment of STPs. The paired t-test result showed a significant difference between two STPs for H2S, 1,3 beta D-Glucans and endotoxins. STPs were advised to reduce the exposure to H2S and bioaerosols as per CPCB guidelines applicable to India to prevent health effects.


Assuntos
Poluentes Ocupacionais do Ar , Poluentes Ambientais , Exposição Ocupacional , Poluentes Ocupacionais do Ar/análise , Poeira/análise , Endotoxinas/análise , Gases , Glucanos/análise , Humanos , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Esgotos
4.
Environ Res ; 213: 113655, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35716813

RESUMO

In the current scenario where more and more products containing nanomaterials are on the technological or pharmaceutical market, it is crucial to have a thorough knowledge of their toxicity before proposing possible applications. A proper analysis of the toxicity of the nanoproducts should include both in vitro and in vivo biological approaches and should consider that the synthesis and purification methods of nanomaterials may affect such toxicity. In the current work, the green synthesis of laminarin embedded ZnO nanoparticles (Lm-ZnO NPs) and their based chitosan capped ZnO nanocomposites (Ch-Lm-ZnO NCmps) is described for the first time. Furthermore, the evaluation of their in vitro cytotoxicity, phytotoxicity, and in vivo (Zebrafish embryo) toxicity was described. First, the green synthesized Lm-ZnO NPs and Ch-Lm-ZnO NCmps were fully physicochemically characterized. Lm-ZnO NPs were greatly agglomerated and had a spindle morphology ranging from 100 to 350 nm, while Ch-Lm-ZnO NCmps had irregular rod shape with flake-like structure clusters randomly aggregated with diverse sizes ranging from 20 to 250 nm. The in vitro cytotoxicity assessment of the green synthesized Lm-ZnO NPs and Ch-Lm-ZnO NCmps was carried out in normal human dermal fibroblasts (HDF) cells and human colon cancer (HT-29) cells by MTT assay. Lm-ZnO NPs and Ch-Lm-ZnO NCmps (0.1-500 µg/mL), significantly inhibited the viability of both cell lines, revealing dose-dependent cytotoxicity. Besides, the Lm-ZnO NPs and Ch-Lm-ZnO NCmps significantly affected seed germination and roots and shoots length of mung (Vigna radiata). Moreover, the zebrafish embryo toxicity of Lm-ZnO NPs and Ch-Lm-ZnO NCmps among the various concentrations used (0.1-500 µg/mL) caused deformities, increased mortality and decreased the survival rate of zebrafish embryo dose-dependently.


Assuntos
Quitosana , Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Animais , Quitosana/química , Quitosana/toxicidade , Glucanos , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Nanopartículas/química , Peixe-Zebra , Óxido de Zinco/química , Óxido de Zinco/toxicidade
5.
Medicina (Kaunas) ; 57(7)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206911

RESUMO

Background and Objectives: Overtreatment with antifungal drugs is often observed. Antifungal stewardship (AFS) focuses on optimizing the treatment for invasive fungal diseases. The objective of the present study was to evaluate the utility of a post-prescription audit plus beta-D-glucan (BDG) assessment on reducing echinocandin use in persons with suspected invasive candidiasis. Materials and Methods: This is a prospective, pre-post quasi-experimental study of people starting echinocandins for suspected invasive candidiasis. The intervention of the study included review of each echinocandin prescription and discontinuation of treatment if a very low probability of fungal disease or a negative BDG value were found. Pre-intervention data were compared with the intervention phase. The primary outcome of the study was the duration of echinocandin therapy. Secondary outcomes were length of hospital stay and mortality. Results: Ninety-two echinocandin prescriptions were reviewed, 49 (53.3%) in the pre-intervention phase and 43 (46.7%) in the intervention phase. Discontinuation of antifungal therapy was possible in 21 of the 43 patients in the intervention phase (48.8%). The duration of echinocandin therapy was 7.4 (SD 4.7) in the pre-intervention phase, 4.1 days (SD 2.9) in persons undergoing the intervention, and 8.6 (SD 7.3) in persons in whom the intervention was not feasible (p at ANOVA = 0.016). Length of stay and mortality did not differ between pre-intervention and intervention phases. Conclusions: An intervention based on pre-prescription restriction and post-prescription audit when combined with BDG measurement is effective in optimizing antifungal therapy by significantly reducing excessive treatment duration.


Assuntos
Candidíase Invasiva , Equinocandinas , Antifúngicos/uso terapêutico , Candidíase Invasiva/diagnóstico , Candidíase Invasiva/tratamento farmacológico , Equinocandinas/uso terapêutico , Glucanos , Humanos , Prescrições , Estudos Prospectivos
6.
Int J Biol Macromol ; 186: 544-553, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34273338

RESUMO

In this study, cost-effective substrates such as cassava starch, corn steep liquor (CSL) and soybean meal hydrolysate (SMH) were used for pullulan production by Aureobasidium pullulans CCTCC M 2012259. The medium was optimized using response surface methodology (RSM) and artificial neural network (ANN) approaches, and analysis of variance indicated that the ANN model achieved higher prediction accuracy. The optimal medium predicted by ANN was used to produce high molecular weight pullulan in high yield. SMH substrates increased both biomass and pullulan titer, while CSL substrates maintained higher pullulan molecular weight. Results of kinetic parameters, key enzyme activities and intracellular uridine diphosphate glucose contents revealed the physiological mechanism of changes in pullulan titer and molecular weight using different substrates. Economic analysis of batch pullulan production using different substrates was performed, and the cost of nutrimental materials for CSL and SMH substrates was decreased by 46.1% and 49.9%, respectively, compared to the control using glucose and yeast extract as substrates, which could improve the competitiveness of pullulan against other polysaccharides in industrial applications.


Assuntos
Aureobasidium/enzimologia , Glucanos/metabolismo , Glycine max/metabolismo , Microbiologia Industrial , Manihot/metabolismo , Amido/metabolismo , Zea mays/metabolismo , Análise Custo-Benefício , Glucanos/economia , Microbiologia Industrial/economia , Cinética , Manihot/economia , Peso Molecular , Redes Neurais de Computação , Amido/economia
7.
Carbohydr Polym ; 260: 117505, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33712177

RESUMO

Exopolysaccharide (EPS) secretion by Sclerotium rolfsii ATCC 201126 in submerged cultures, already identified as high-osmolarity responsive, was assessed by reducing C-source without compromising EPS yields. A designed medium with 80 g sucrose L-1 (MOPT80) was tested at 3 L-bioreactor scale at different temperature, agitation, aeration and pH (uncontrolled vs. controlled) values. Optimal operative conditions (200 rpm, 28 °C, 0.5 vvm and initial pH -pHi- 4.5) were validated, as well as the possibility to work at pHi 5.5 to reduce biomass production. Purified EPSs produced in MOPT80 at optimal and other valid operative conditions exhibited refined grade (<1 % proteins and ash, 3-4 % reducing sugars, 87-99 % total sugars). EPS purity, MW and rheological parameters led to discourage pH controlled at 4.5. Relatively constant MW (6-8 × 106 Da) and outstanding viscosifying ability were found. Polyphasic EPS analysis (titre, purity, macromolecular features and rheological fitness) would support to properly select production conditions.


Assuntos
Basidiomycota/crescimento & desenvolvimento , Reatores Biológicos , Glucanos/metabolismo , Basidiomycota/metabolismo , Biomassa , Reatores Biológicos/economia , Meios de Cultura/química , Concentração de Íons de Hidrogênio , Reologia , Temperatura
8.
Clin Infect Dis ; 72(Suppl 2): S102-S108, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33709130

RESUMO

Detection of 1,3-ß-d-glucan (BDG) in serum has been evaluated for its inclusion as a mycological criterion of invasive fungal infections (IFI) according to EORTC and Mycoses Study Group (MSG) definitions. BDG testing may be useful for the diagnosis of both invasive aspergillosis and invasive candidiasis, when interpreted in conjunction with other clinical/radiological signs and microbiological markers of IFI. However, its performance and utility vary according to patient population (hematologic cancer patients, solid-organ transplant recipients, intensive care unit patients) and pretest likelihood of IFI. The objectives of this article are to provide a systematic review of the performance of BDG testing and to assess recommendations for its use and interpretation in different clinical settings.


Assuntos
Candidíase Invasiva , Infecções Fúngicas Invasivas , beta-Glucanas , Adulto , Candidíase Invasiva/diagnóstico , Glucanos , Humanos , Infecções Fúngicas Invasivas/diagnóstico , Sensibilidade e Especificidade
9.
Carbohydr Polym ; 256: 117559, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483061

RESUMO

Water-extracted polysaccharides from Russula vinosa Lindblad (WRP) were separated into three fractions (WRP-1, WRP-2 and WRP-3) by gradient ethanol precipitation and gel chromatography. Structural characterization indicated that WRP-1 was a branched ß-(1→3)-glucan and exhibited rigid helical conformation in aqueous solution with Mw of 2,180 kDa and radius of gyration (Rg) of 123.4 nm. The galactoglucan of WRP-2 and WRP-3 were mainly composed of →6)-Galp-(1→ and →4)-Glcp-(1→ terminated by glucose and mannose, presenting much lower Mw (392 and 93.6 kDa) and Rg (57.6 and 42.6 nm), and more incompact flexible conformation than WRP-1. All fractions showed potential immunostimulatory activity by promoting macrophage proliferation, phagocytosis, as well as the release of nitric oxide and cytokines (TNF-α and IL-1ß). WRP-1 with unique structure and conformation showed the best immunostimulatory effects among them. This study suggests that WRP could be explored as natural immunostimulator used in the food and pharmaceutical industry.


Assuntos
Basidiomycota/química , Galactanos/química , Glucanos/química , Polissacarídeos Bacterianos/química , beta-Glucanas/química , Animais , Técnicas de Cultura de Células , Proliferação de Células , Sobrevivência Celular , Fracionamento Químico , Cromatografia em Gel , Vermelho Congo/química , Citocinas/metabolismo , Indústria Farmacêutica , Etanol , Indústria Alimentícia , Glucose/química , Macrófagos/metabolismo , Espectroscopia de Ressonância Magnética , Manose/química , Camundongos , Fagocitose , Polissacarídeos/química , Células RAW 264.7 , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Methods Mol Biol ; 2149: 315-325, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32617942

RESUMO

The deposition and modulation of constituent polymers of plant cell walls are profoundly important events during plant development. Identification of specific polymers within assembled walls during morphogenesis and in response to stress conditions represents a major goal of plant cell biologists. Arabidopsis thaliana is a model organism that has become central to research focused on fundamental plant processes including those related to plant wall dynamics. Its fast life cycle and easy access to a variety of mutants and ecotypes of Arabidopsis have stimulated the need for rapid assessment tools to probe its wall organization at the cellular and subcellular levels. We describe two rapid assessment techniques that allow for elucidation of the cell wall polymers of root hairs and high-resolution analysis of surface features of various vegetative organs. Live organism immunolabeling of cell wall polymers employing light microscopy and confocal laser scanning microscopy can be effectively performed using a large microplate-based screening strategy (see Figs. 1 and 2). Rapid cryofixation and imaging of variable pressure scanning electron microscopy also allows for imaging of surface features of all portions of the plant as clearly seen in Fig. 3.


Assuntos
Arabidopsis/metabolismo , Biopolímeros/metabolismo , Parede Celular/química , Plântula/metabolismo , Arabidopsis/ultraestrutura , Parede Celular/ultraestrutura , Glucanos/metabolismo , Raízes de Plantas/metabolismo , Plântula/ultraestrutura
11.
Int J Biol Macromol ; 163: 1196-1207, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32622769

RESUMO

Athelia rolfsii TEMG (MH 236106) an exopolysaccharide (EPS) producing fungal strain was isolated and identified. Extraction, purification, characterization, antimicrobial, antioxidant, antiviral and antitumor activities of the polysaccharide were investigated. It characterized as a homopolysaccharide of glucose with a molecular weight of 345.622 kDa. The identification of the polysaccharide was conducted using scanning electron microscopy, energy dispersive X-ray analysis, 1H and 13C NMR spectra. The existence of ß-1,3 and ß-1,6 linkages suggests that EPS could be scleroglucan. The purified scleroglucan showed considerable antibacterial and antioxidant activities. The results indicated that, there was no cytotoxicity on normal cell (W138) and no effect on tumor cell lines including HepG2 and PC3 showing IC50 of 5096.83, 5885.80 and 4803.90 µg/mL, respectively. The results showed also that Sclg could reduce the cytopathic effect by 50% (EC50) at 15 and 50 µg/mL of herpes simplex virus type-1 (HSV-1) and influenza virus (H5N1), respectively.


Assuntos
Basidiomycota/química , Glucanos/química , Glucanos/farmacologia , Basidiomycota/classificação , Basidiomycota/genética , Sobrevivência Celular/efeitos dos fármacos , Fenômenos Químicos , Humanos , Estrutura Molecular , Peso Molecular , Monossacarídeos/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Reologia , Relação Estrutura-Atividade
12.
Bioresour Technol ; 304: 122990, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32078901

RESUMO

In this study, a novel Aureobasidium pullulans GXL-1 strain without melanin secretion was isolated for efficient polymalic acid (PMA) production. The PMA produced by GXL-1 was characterized, and its molecular mass was determined to be 1.621 kDa by gel permeation chromatography. Liquefied corn starch was shown to replace glucose for PMA production by GXL-1 through simultaneous saccharification and fermentation. The PMA titer obtained from batch fermentation was up to 49.0 ± 1.6 g/L in a 10 L fermentor, and the PMA yield and productivity obtained from repeated-batch fermentation were up to 0.50 g/g and 0.34 g/L·h, respectively. Furthermore, process design and techno-economic analysis were performed at an annual output level of 5000 metric tons by SuperPro Designer. Results showed that the production cost of $2.046/kg and payback period of 6.9 years were achieved by repeated-batch fermentation; this provides an economically feasible strategy for industrial-scale production of PMA.


Assuntos
Amido , Zea mays , Fermentação , Glucanos , Malatos , Polímeros
13.
Int J Biol Macromol ; 156: 1104-1111, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31756470

RESUMO

Chitin-glucan complex (CGC) was used for the first time for the preparation of hydrogels. Alkali solvent systems, NaOH and KOH solutions, either at 1 or 5 mol/L, were used for CGC dissolution using a freeze-thaw procedure (freezing at -20 °C and thawing at room temperature; four cycles). The CGC solutions thus obtained were subjected to dialysis that induced the spontaneous gelation of the biopolymer, yielding translucid hydrogels with a yellowish coloration. Although all CGC hydrogels exhibited porous microstructures, high water content (above 97%) and good mechanical properties, their morphology, viscoelastic properties and texture were influenced by the type of solvent system used for CGC dissolution, as well as by their ionic strength. The K-based hydrogels presented a less compact network with larger pores and exhibited lower elastic properties. The Na-based hydrogels, on the other hand, exhibited a denser structure with smaller pores and a stiffer gel structure. These results show that it is possible to prepare CGC hydrogels with differing characteristics that can be suitable for different applications. Furthermore, all hydrogels were non-cytotoxic towards L929 fibroblasts and HaCaT keratinocytes. This study demonstrates CGC can be used to prepare biocompatible hydrogels with properties render them promising biomaterials.


Assuntos
Quitina/química , Glucanos/química , Hidrogéis/química , Leveduras/química , Materiais Biocompatíveis/química , Reologia
14.
Br J Community Nurs ; 24(Sup9): S33-S37, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31479338

RESUMO

One of the biggest challenges faced by healthcare providers is the treatment of chronic, non-healing wounds. This paper reports for the first time in the UK the results of five case studies in which a novel regenerating matrix-based therapy, CACIPLIQ20, was used. CACIPLIQ20 is a heparan sulphate mimetic designed to replace the destroyed heparan sulphate in the extracellular matrix of wound cells. All five patients in this case series had chronic, non-healing ulcers that had not improved with conventional care. Treatment included two applications of CACIPLIQ20 per week, for a maximum of 12 weeks. Three of the five wounds healed completely, and the remaining two showed significant improvements in size and quality. The treatment was well tolerated by the patients and also led to a significant reduction in pain. Moreover, CACIPLIQ20 treatment was found to be highly cost-effective when compared to conventional care, with the potential to save healthcare systems significant resources. Further studies are needed to build a strong evidence base on the use of this product, but these preliminary findings are certainly promising.


Assuntos
Bandagens , Glucanos/uso terapêutico , Heparitina Sulfato/análogos & derivados , Inflamação , Úlcera por Pressão/enfermagem , Ferida Cirúrgica/enfermagem , Úlcera Varicosa/enfermagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Amputação Cirúrgica , Doença Crônica , Análise Custo-Benefício , Matriz Extracelular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Vasculares Periféricas , Regeneração , Ferimentos e Lesões/enfermagem
15.
Plant Physiol Biochem ; 133: 134-141, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30408676

RESUMO

Elicitor-induced resistance against diseases is an attractive strategy that could contribute to reduce the use of fungicides for plant protection. However, activation of defenses has an energetic cost that plants have to fuel by a mobilization of their primary metabolism with possible adverse effect on their physiology. In this context, this study was performed to determine whether elicitor-induced resistance of grapevine leaves against downy mildew impacted its development and metabolism. The elicitor PS3 (sulfated ß-glucan laminarin) was sprayed on grapevine herbaceous cuttings grown in greenhouses once or three times, and its impact was studied on young and older grapevine leaves, prior to, and after Plasmopara viticola inoculation. PS3 did not affect grapevine development during the time course of the experiment. A metabolomic analysis, mainly focused on primary metabolites, highlighted a leaf age dependent effect of PS3 treatment. Nitrogen compounds, and sugars to a lesser extent, were impacted. The results obtained complete the current knowledge of the impact of elicitor-induced resistance on plant physiology. They will be helpful to guide further experiments required to better determine the costs and benefits of elicitor-induced resistance in plants.


Assuntos
Resistência à Doença/efeitos dos fármacos , Glucanos/farmacologia , Oomicetos/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Folhas de Planta , Vitis , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Vitis/metabolismo , Vitis/microbiologia
16.
Cell Mol Biol (Noisy-le-grand) ; 64(8): 22-26, 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-29981680

RESUMO

Pullulan is an important polysaccharide with several potential applications in food science, pharmaceutical and cosmetic industries, but high costs of pullulan production are the main limitation for commercial utilization. Therefore, a cost-effective process for pullulan production was developed using fig syrup as an exclusive nutrient source. In particular, the feasibility of using low quality fig syrup as a supplemental substrate for pullulan gum production by Aureobasidium pullulans was investigated. Fermentation was carried out over a range of fig syrup and sucrose degrees Brix (5-15%). Maximum pullulan gum production was observed after 96h using 12.5% fig syrup, yielding approximately14.06 g/L. This value of pullulan production (14.06 g/L) was higher than the amount of pullulan produced using sucrose as substrate (5.01 g/L). In conclusion, fig syrup was an effective substrate for pullulan production by Aureobasidium pullulans, and, therefore, this byproduct deserves attention for the cost-effective and environmentally friendly pullulan production.


Assuntos
Ficus/química , Aditivos Alimentares/química , Glucanos/química , Polissacarídeos/química , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Carbono/química , Análise Custo-Benefício , Fermentação , Aditivos Alimentares/metabolismo , Glucanos/economia , Humanos , Nitrogênio/química
17.
J Phycol ; 54(4): 529-538, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29889303

RESUMO

Euglena gracilis Z and a "sugar loving" variant strain E. gracilis var. saccharophila were investigated as producers of paramylon, a ß-1,3-glucan polysaccharide with potential medicinal and industrial applications. The strains were grown under diurnal or dark growth conditions on a glucose-yeast extract medium supporting high-level paramylon production. Both strains produced the highest paramylon yields (7.4-8 g · L-1 , respectively) while grown in the dark, but the maximum yield was achieved faster by E. gracilis var. saccharophila (48 h vs. 72 h). The glucose-to-paramylon yield coefficient Ypar/glu  = 0.46 ± 0.03 in the E. gracilis var. saccharophila cultivation, obtained in this study, is the highest reported to date. Proteomic analysis of the metabolic pathways provided molecular clues for the strain behavior observed during cultivation. For example, overexpression of enzymes in the gluconeogenesis/glycolysis pathways including fructokinase-1 and chloroplastic fructose-1,6-bisphosphatase (FBP) may have contributed to the faster rate of paramylon accumulation in E. gracilis var. saccharophila. Differentially expressed proteins in the early steps of chloroplastogenesis pathway including plastid uroporphyrinogen decarboxylases, photoreceptors, and a highly abundant (68-fold increase) plastid transketolase may have provided the E. gracilis var. saccharophila strain an advantage in paramylon production during diurnal cultivations. In conclusion, the variant strain E. gracilis var. saccharophila seems to be well suited for producing large amounts of paramylon. This work has also resulted in the identification of molecular targets for future improvement of paramylon production in E. gracilis, including the FBP and phosophofructokinase 1, the latter being a key regulator of glycolysis.


Assuntos
Euglena gracilis/metabolismo , Glucanos/metabolismo , Luz , beta-Glucanas/metabolismo , Proteínas de Algas/análise , Proteoma/análise , Proteínas de Protozoários/análise
18.
Curr Drug Deliv ; 15(2): 235-246, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-28571542

RESUMO

BACKGROUND: Chemotherapy still encounters a serious drawback, the lack of selectivity of anticancer drugs toward neoplastic cells, thus, the normal cells are affected by the cytotoxic action of the drugs. This causes a narrow therapeutic index in most anticancer drugs. OBJECTIVE: We describe the preparation of pullulan-tocopherol succinate-folic acid (Pu-TS-FA) micelles for the first time to targeted delivery of Epirubicin (EPI) to Hela and MCF-7 cell lines. METHODS: We confirmed the structure of conjugate using spectroscopic methods. The degree of substitution for both folic acid and tocopherol succinate was calculated using 1HNMR. We prepared the micelles via direct dissolution method. All the physicochemical properties of micelles including size, zeta potential, polydispersity index (PDI), critical micelle concentration (CMC), entrapment efficiency (EE %) and release efficiency (RE24%) were determined. The morphology of particles was studied using transmission electron microscopy (TEM), and the in-vitro cell cytotoxicity of EPI loaded micelles was studied using MTT assay on MCF-7 and Hela cell lines. RESULTS: The optimized micelles showed the particle size of 149.5 nm, the zeta potential of -6.49 mV, a polydispersity index of 0.259 ± 0.07, LE% of 88 %, and RE24% of 63 ± 2.45 % with a relatively low CMC 194.87 µg/ml. TEM showed the relatively uniform spherical structure for particles and in vitro MTT assay showed that EPI loaded micelles were more toxic on Hela cell line than MCF7 as expected. CONCLUSION: Since the Pu-TS-FA micelle could improve the anticancer activity of epirubicin and would be a promising candidate for EPI treatment of cancers.


Assuntos
Portadores de Fármacos/química , Epirubicina/química , Epirubicina/farmacologia , Ácido Fólico/química , Glucanos/química , Polímeros/química , alfa-Tocoferol/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Células HeLa , Humanos , Células MCF-7 , Micelas , Tamanho da Partícula
19.
Plant J ; 93(2): 211-226, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29160933

RESUMO

Xyloglucan has been hypothesized to bind extensively to cellulose microfibril surfaces and to tether microfibrils into a load-bearing network, thereby playing a central role in wall mechanics and growth, but this view is challenged by newer results. Here we combined high-resolution imaging by field emission scanning electron microscopy (FESEM) with nanogold affinity tags and selective endoglucanase treatments to assess the spatial location and conformation of xyloglucan in onion cell walls. FESEM imaging of xyloglucanase-digested cell walls revealed an altered microfibril organization but did not yield clear evidence of xyloglucan conformations. Backscattered electron detection provided excellent detection of nanogold affinity tags in the context of wall fibrillar organization. Labelling with xyloglucan-specific CBM76 conjugated with nanogold showed that xyloglucans were associated with fibril surfaces in both extended and coiled conformations, but tethered configurations were not observed. Labelling with nanogold-conjugated CBM3, which binds the hydrophobic surface of crystalline cellulose, was infrequent until the wall was predigested with xyloglucanase, whereupon microfibril labelling was extensive. When tamarind xyloglucan was allowed to bind to xyloglucan-depleted onion walls, CBM76 labelling gave positive evidence for xyloglucans in both extended and coiled conformations, yet xyloglucan chains were not directly visible by FESEM. These results indicate that an appreciable, but still small, surface of cellulose microfibrils in the onion wall is tightly bound with extended xyloglucan chains and that some of the xyloglucan has a coiled conformation.


Assuntos
Parede Celular/ultraestrutura , Glucanos/ultraestrutura , Microscopia Eletrônica de Varredura/métodos , Plantas/ultraestrutura , Xilanos/ultraestrutura , Parede Celular/metabolismo , Celulose/metabolismo , Celulose/ultraestrutura , Glucanos/metabolismo , Glicosídeo Hidrolases/metabolismo , Microfibrilas/metabolismo , Microfibrilas/ultraestrutura , Plantas/metabolismo , Xilanos/metabolismo
20.
Biomacromolecules ; 19(1): 150-157, 2018 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-29182312

RESUMO

Knowledge gaps in the biosafety data of the nanocellulose (NC) for biomedical use through various routes of administration call for closer look at health and exposure evaluation. This work evaluated the potentially immunogenic contaminants levels, for example, endotoxin and (1,3)-ß-d-glucan, in four representative NCs, that is, wood-based NCs and bacterial cellulose (BC). The hot-water extracts were analyzed with ELISA assays, HPSEC-MALLS, GC, and NMR analysis. Varying levels of endotoxin and (1,3)-ß-d-glucan contaminats were found in these widely used NCs. Although the ß-(1,3)-d-glucan was not detected from the NMR spectra due to the small extract samples amount (2-7 mg), the anomerics and highly diastereotopic 6-CH2 signals may suggest the presence of ß-(1,4)-linkages with ß-(1,6) branching in the polysaccharides of NCs' hot-water extracts, which were otherwise not detectable in the enzymatic assay. In all, the article highlights the importance of monitoring various water-soluble potentially immunogenic contaminants in NC for biomedical use.


Assuntos
Bactérias/metabolismo , Celulose/química , Endotoxinas/metabolismo , Glucanos/metabolismo , Nanotecnologia , Madeira/química , Cromatografia Gasosa , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Ensaio de Imunoadsorção Enzimática , Espectroscopia de Ressonância Magnética
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