Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 40
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
J Agric Food Chem ; 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39436683

RESUMO

Akkermansia muciniphila (A. muciniphila) possesses health-promoting properties. Nevertheless, A. muciniphila enrichment remains a challenging endeavor. Quercetin-3-O-rutinose-7-O-α-l-rhamnoside (QRR), a flavonoid found in lychee pulp, has a unique double-substituted glycosylated structure, requiring a specific intestinal microbiota for effective metabolism. Here, QRR was fermented using a coculture of Bacteroides uniformis and A. muciniphila, and the interactions between the two were elucidated in terms of QRR regulation of microbial growth changes and metabolic properties. The results demonstrated that QRR effectively promoted the proliferation of A. muciniphila based on the metabolic action of B. uniformis in vitro, which was evidenced by a notable increase in the number of viable bacteria. Furthermore, the coculture sample exhibited a significant increase in SCFAs. Qualitative analysis of metabolites by UPLC-ESI-Triple-TOF-MS/MS showed that B. uniformis could release sugars on QRR to produce quercetin-3-O-glucoside-7-O-α-rhamnoside and further quercetin. In the coculture and B. uniformis culture, quercetin was converted to taxifolin, which was identified as a crucial intermediate in the metabolism of QRR. Notably, the metabolite kaempferol was only detected in the coculture. The present study reveals the interaction between QRR and the coculture of A. muciniphila and B. uniformis, providing a practical basis for the potential prebiotic value of QRR.

2.
Heliyon ; 10(19): e38283, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39386795

RESUMO

Corosolic acid (CA), a pentacyclic triterpenoid, exhibits remarkably low hydrophilicity, restricting its application in aqueous systems. To enhance its hydrophilicity, we optimised nanoemulsion preparation conditions, resulting in a stable corosolic acid nanoemulsion system. By screening the oil phase, surfactant, and cosurfactant, along with investigating the mass ratio of surfactant and cosurfactant and the preparation temperature, we achieved an optimal corosolic acid nanoemulsion. We measured the particle size, polydispersity coefficient, and Zeta potential of the optimised formulation. The nanoemulsion's sustained-release effect, stability, and antibacterial activity were subsequently examined. The optimised formulation comprised ethyl oleate, cremophor EL, and Tween 80 (1.5:1), combined with ethanol in a ratio of 1:9:2.25 (w/w/w), and was prepared at 30 °C. This optimised corosolic acid nanoemulsion exhibited uniform particle size distribution, favourable dispersion, and notable slow-release capabilities. Importantly, the nanoemulsion demonstrated exceptional stability. In comparison to the positive control's bacteriostatic zone diameter, it was evident that the CA nanoemulsion (1.06 ± 0.11 mm) and blank nanoemulsion (1.03 ± 0.05 mm) both displayed notable inhibitory activity against S. aureus. Our findings established a solid foundation for the potential application of CA nanoemulsion in the food, cosmetics, and pharmaceutical industries. However, the application of CA nanoemulsion in real food or drug systems has not been explored yet.

3.
Molecules ; 29(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38611855

RESUMO

Quinoa, known as the "golden grain" for its high nutritional value, has polysaccharides as one of its sources of important nutrients. However, the biological functions of quinoa polysaccharides remain understudied. In this study, two crude polysaccharide extracts of quinoa (Q-40 and Q-60) were obtained through sequential precipitation with 40% and 60% ethanol, with purities of 58.29% (HPLC) and 62.15% (HPLC) and a protein content of 8.27% and 9.60%, respectively. Monosaccharide analysis revealed that Q-40 contained glucose (Glc), galacturonic acid (GalA), and arabinose (Ara) in a molar ratio of 0.967:0.027:0.006. Q-60 was composed of xylose (xyl), arabinose (Ara), galactose, and galacturonic acid (GalA) with a molar ratio of 0.889:0.036:0.034:0.020. The average molecular weight of Q-40 ranged from 47,484 to 626,488 Da, while Q-60 showed a range of 10,025 to 47,990 Da. Rheological experiments showed that Q-40 exhibited higher viscosity, while Q-60 demonstrated more elastic properties. Remarkably, Q-60 showed potent antioxidant abilities, with scavenging rates of 98.49% for DPPH and 57.5% for ABTS. Antibacterial experiments using the microdilution method revealed that Q-40 inhibited the growth of methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli), while Q-60 specifically inhibited MRSA. At lower concentrations, both polysaccharides inhibited MDA (MD Anderson Cancer Center) cell proliferation, but at higher concentrations, they promoted proliferation. Similar proliferation-promoting effects were observed in HepG2 cells. The research provides important information in the application of quinoa in the food and functional food industries.


Assuntos
Chenopodium quinoa , Ácidos Hexurônicos , Staphylococcus aureus Resistente à Meticilina , Arabinose , Escherichia coli , Grão Comestível
4.
Int J Biol Macromol ; 258(Pt 2): 128833, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38128806

RESUMO

Natural polysaccharides exhibit numerous beneficial properties, such as antioxidant, antitumor, hypoglycemic, and hypolipidemic activities. Moringa oleifera seeds are of high dietary and therapeutic value which drew a lot of attention. However, the regulation effect on anti-inflammatory activity of polysaccharides remains to be studied. Herein, novel bioactive polysaccharides (MOSP-1) were extracted from Moringa oleifera seeds, and the anti-inflammatory properties of MOSP-1 were uncovered. Ultrasound-assisted extraction (UAE) was used to prepare the polysaccharides with optimized conditions (70 °C, 43 min, and liquid-solid-ratio 15 mL/g). Then, DEAE-Sepharose Fast Flow columns were applied to isolate and purify MOSP-1. Rhamnose, arabinose, galactose, and glucose were identified as the monosaccharide constituents of MOSP-1, with a molecular weight of 5.697 kDa. Their proportion in molarity was 1:0.183:0.108:0.860 and 8 types of glycosidic linkages were discovered. Bioactive assays showed that MOSP-1 possessed scavenging activities against DPPH and ABTS radicals, confirming its potential antioxidation efficacy. In vitro experiments revealed that MOSP-1 could reduce the expression of inflammation-related cytokines, inhibit the activation of ERK, JNK, and p38 (the MAPK signaling pathway), and enhance phagocytic functions. This study indicates that polysaccharides (MOSP-1) from Moringa oleifera seeds with anti-inflammatory properties may be used for functional food and pharmaceutical product development.


Assuntos
Moringa oleifera , Moringa oleifera/química , Ultrassom , Polissacarídeos/química , Antioxidantes/química , Anti-Inflamatórios , Sementes/química
5.
Front Nutr ; 10: 1158158, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37090775

RESUMO

Cyclocarya paliurus (C. paliurus), a nutritional and nutraceutical resource for human and animal diets, has been constantly explored. The available biological components of C. paliurus were triterpenoids, polysaccharides, and flavonoids. Recent studies in phytochemical-phytochemistry; pharmacological-pharmacology has shown that C. paliurus performed medicinal value, such as antihypertensive, antioxidant, anticancer, antimicrobial, anti-inflammatory and immunological activities. Furthermore, C. paliurus and its extracts added to drinks would help to prevent and mitigate chronic diseases. This review provides an overview of the nutritional composition and functional applications of C. paliurus, summarizing the research progress on the extraction methods, structural characteristics, and biological activities. Therefore, it may be a promising candidate for developing functional ingredients in traditional Chinese medicine. However, a more profound understanding of its active compounds and active mechanisms through which they perform biological activities is required. As a result, the plant needs further investigation in vitro and in vivo.

6.
J Agric Food Chem ; 71(12): 4817-4824, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36935587

RESUMO

The goal of this study was to expand the applications of bamboo leaf flavonoids (BLFs) by improving their lipophilicity through enzymatic acylation with vinyl cinnamate. Characterization of the acylated BLFs using Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, high-resolution electrospray ionization mass spectrometry, electrospray ionization with tandem mass spectrometry, and 1H nuclear magnetic resonance spectroscopy indicated that acylation occurred at the C6-OH position of glucoside moieties. The highest degree of acylation (18.61%) was obtained by reacting BLFs with vinyl cinnamate (1:5, w/w) at 60 °C for 48 h. Acylation significantly improved the lipophilicity of BLFs and their capacity to inhibit lipid peroxidation, as evidenced by the reduced production of lipid hydroperoxides and malondialdehyde in rapeseed oil and rapeseed oil-in-water emulsions during storage at 37 °C for 15 days. The study findings provide important data that will enable the use of BLFs in lipid or lipophilic matrices, such as oil-based foods.


Assuntos
Antioxidantes , Flavonoides , Antioxidantes/química , Flavonoides/química , Óleo de Brassica napus , Acilação , Folhas de Planta/química
7.
J Control Release ; 357: 274-286, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36958401

RESUMO

The application of numerous chemotherapeutic drugs has been limited due to poor solubility, adverse side effects, and even multidrug resistance in patients. Polymeric micelles with reversibly cross-linked structures provide a promising solution to these issues. Herein, we optimized and synthesized programable-released disulfide cross-linked micelle (PDCM) based on our previous well-defined dendrimers to deliver the antitumor drug betulinic acid (BA) and paclitaxel (PDCM@PTX) and evaluated the therapeutic efficacy of multidrug-resistant (MDR) simulative orthotopic intraperitoneal ovarian cancer mice models. Comprehensive results demonstrated that PDCM@PTX formed stable nanoparticles able to improve the pharmacokinetic profile and circulation time of PTX, allowing for increased tumor penetration. Furthermore, in the tumor microenvironment, the programable-switches (ester bonds and disulfide cross-linking) of PDCM@PTX were cleaved by the high concentration of glutathione (tumor microenvironment) and esterase (intracellular) present in the tumor, allowing for in situ release of PTX and BA, resulting in intensive therapeutic efficacy in MDR ovarian cancer.


Assuntos
Antineoplásicos , Neoplasias Ovarianas , Humanos , Feminino , Animais , Camundongos , Sistemas de Liberação de Medicamentos/métodos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Paclitaxel/química , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Micelas , Dissulfetos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Microambiente Tumoral
8.
Food Chem ; 410: 135384, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36610094

RESUMO

Magnetic nanometer combined with microwave thawing (MN-MT) could become a novel solution to challenges uneven and overheating of microwave thawing (MT), while retaining high thawing efficiency, compared to conventional water immersion thawing (WT). In this study, MN-MT was applied to thaw fruit (lychee as an example) for the first time, and was evaluated by comparison with WT, MT and water immersion combined with microwave thawing (WI-MT). Results showed that MN-MT could significantly shorten the thawing time of frozen lychee by 80.67%, 25.86% and 18.83% compared to WT, MT and WI-MT, respectively. Compared to WT, MN-MT was the only thawing treatment which significantly enhanced the release of quercetin-3-O-rutinose-7-O-α-l-rhamnoside, according to HPLC-DAD. Meanwhile, thermal-sensitive procyanidin B2, phenylpropionic acid and protocatechuic acid were found to be protected from degradations only by MN-MT based on UPLC-ESI-QTOF-MS/MS results. In summary, MN-MT is a potential novel treatment for rapid thawing and quality maintenance of frozen fruits.


Assuntos
Frutas , Litchi , Micro-Ondas , Espectrometria de Massas em Tandem , Fenóis , Água
9.
Crit Rev Food Sci Nutr ; 63(29): 9816-9842, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35587161

RESUMO

Advanced glycation end products (AGEs) are formed in non-enzymatic reaction, oxidation, rearrangement and cross-linking between the active carbonyl groups of reducing sugars and the free amines of amino acids. The Maillard reaction is related to sensory characteristics in thermal processed food, while AGEs are formed in food matrix in this process. AGEs are a key link between carbonyl stress and neurodegenerative disease. AGEs can interact with receptors for AGEs (RAGE), causing oxidative stress, inflammation response and signal pathways activation related to neurodegenerative diseases. Neurodegenerative diseases are closely related to gut microbiota imbalance and intestinal inflammation. Polyphenols with multiple hydroxyl groups showed a powerful ability to scavenge ROS and capture α-dicarbonyl species, which led to the formation of mono- and di- adducts, thereby inhibiting AGEs formation. Neurodegenerative diseases can be effectively prevented by inhibiting AGEs production, and interaction with RAGEs, or regulating the microbiota-gut-brain axis. These strategies include polyphenols multifunctional effects on AGEs inhibition, RAGE-ligand interactions blocking, and regulating the abundance and diversity of gut microbiota, and intestinal inflammation alleviation to delay or prevent neurodegenerative diseases progress. It is a wise and promising strategy to supplement dietary polyphenols for preventing neurodegenerative diseases via AGEs-RAGE axis and microbiota-gut-brain axis regulation.


Assuntos
Produtos Finais de Glicação Avançada , Doenças Neurodegenerativas , Humanos , Produtos Finais de Glicação Avançada/metabolismo , Eixo Encéfalo-Intestino , Doenças Neurodegenerativas/prevenção & controle , Suplementos Nutricionais , Polifenóis/farmacologia , Inflamação/prevenção & controle
10.
Front Nutr ; 9: 1053422, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438772

RESUMO

Clanis Bilineata Tingtauica Mell Protein (CBTMP) was a kind of natural full-price protein which has a bright application prospect in the food industry. Since the functional properties of protein can be significantly affected by drying method, this study aims to explore the effect of different drying methods, namely freeze drying (FD), vacuum drying (VD),and hot-air drying (HD) on the structure and functional properties of CBTMP. The results showed that the degree of oxidation of CBTMP was found to be in the following order: HD > VD > FD. Functional characteristics revealed that the CBTMP prepared by VD had relatively high foaming ability (150.24 ± 5.34°C) among three drying methods. However, the stability of emulsion and rheological properties prepared by FD was superior to other samples. Differential scanning calorimeter (DSC) showed CBTMP made by HD had the relatively good thermal stability (Tp = 91.49 ± 0.19 °C), followed by VD and FD. Digestive properties reflected that heating treatment could significantly increase its degree of hydrolysis in vitro. To sum up, the research could provide experimental guidance and theoretical support for the preparation method and utilization of CBTMP.

11.
Int J Biol Macromol ; 211: 150-158, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35568148

RESUMO

This study explored the mechanism underlying the interactions between polysaccharides and ovalbumin-ferulic acid (OVA-FA) and the effect of polysaccharides on OVA-FA-stabilized emulsions. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) were used to study the polysaccharide OVA-FA interactions mechanism and to resolve the changes in the protein secondary structure and crystal structure. OVA-FA-polysaccharide-stabilized emulsions were studied using confocal laser scanning microscopy (CLSM), and their rheological properties and stability were determined. The results showed that the non-covalent interactions between polysaccharides and OVA-FA led to an increase in the ß-sheet content of OVA and a decrease in the α-helix and random coil contents. The stability of the OVA-FA-polysaccharide-stabilized emulsions was better compared with that of the OVA-FA-stabilized emulsions. By comparing the different OVA-FA-polysaccharide-stabilized emulsions, we observed that OVA-FA-agar did not stabilize the emulsion well, while the OVA-FA-SA- and OVA-FA-KC-stabilized emulsions had good elasticity, and the microstructure and storage stability of the OVA-FA-KC-stabilized emulsion were better. Our findings provide a new perspective for the application of OVA-FA-KC in complex food emulsions.


Assuntos
Ácidos Cumáricos , Polissacarídeos , Emulsões/química , Ovalbumina/química
12.
Toxins (Basel) ; 14(4)2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35448884

RESUMO

Deoxynivalenol (DON), a mycotoxin that contaminates crops such as wheat and corn, can cause severe acute or chronic injury when ingested by animals or humans. This study investigated the protective effect of ferulic acid (FA), a polyphenolic substance, on alleviating the toxicity induced by DON (40 µM) in IPEC-J2 cells. The experiments results showed that FA not only alleviated the decrease in cell viability caused by DON (p < 0.05), but increased the level of superoxide dismutase (SOD) (p < 0.01), glutathione peroxidase (GSH-Px), (catalase) CAT and glutathione (GSH) (p < 0.05) through the nuclear factor erythroid 2-related factor 2 (Nrf2)-epoxy chloropropane Kelch sample related protein-1 (keap1) pathway, and then decreased the levels of intracellular oxidative stress. Additionally, FA could alleviate DON-induced inflammation through mitogen-activated protein kinases (MAPKs) and nuclear factor kappa-B (NF-κB) pathways, down-regulated the secretion of interleukin-6 (IL-6) (p < 0.0001), interleukin-8 (IL-8) (p < 0.05), interleukin-1ß (IL-1ß), interferon-γ (IFN-γ) and further attenuated the DON-induced intracellular apoptosis (10.7% to 6.84%) by regulating the expression of Bcl2-associated X protein (Bax) (p < 0.0001), B-cell lymphoma-2 (Bcl-2) (p < 0.0001), and caspase-3 (p < 0.0001). All these results indicate that FA exhibits a significantly protective effect against DON-induced toxicity.


Assuntos
Fator 2 Relacionado a NF-E2 , Tricotecenos , Animais , Apoptose , Ácidos Cumáricos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Tricotecenos/metabolismo
13.
Molecules ; 27(8)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35458651

RESUMO

Chenopodium quinoa Willd. is recognized to be an excellent nutrient with high nutritional content. However, few genotypes of quinoa were analyzed, so we found a knowledge gap in the comparison of quinoa seeds of different genotypes. This study aims to compare the physicochemical, antioxidant, and anticancer properties of seed oil from three C. quinoa genotypes. Seeds of three genotypes (white, red, and black) were extracted with hexane and compared in this study. The oil yields of these quinoa seeds were 5.68-6.19% which contained predominantly polyunsaturated fatty acids (82.78-85.52%). The total tocopherol content ranged from 117.29 to 156.67 mg/kg and mainly consisted of γ-tocopherol. Total phytosterols in the three oils ranged from 9.4 to 12.2 g/kg. Black quinoa seed oil had the highest phytosterols followed by red and white quinoas. The chemical profile of quinoa seed oils paralleled by their antioxidant and anticancer activities in vitro was positively correlated with the seed coat color. Black quinoa seed oil had the best antioxidant and anti-proliferation effect on HCT 116 cells by the induction of apoptosis in a dose-dependent manner, which may play more significant roles in the chemoprevention of cancer and other diseases related to oxidative stress as a source of functional foods.


Assuntos
Chenopodium quinoa , Fitosteróis , Antioxidantes/análise , Antioxidantes/farmacologia , Chenopodium quinoa/química , Genótipo , Fitosteróis/análise , Fitosteróis/farmacologia , Óleos de Plantas/química , Sementes/química
14.
Ultrason Sonochem ; 80: 105823, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34749046

RESUMO

Clanis Bilineata Tingtauica Mell Protein (CBTMP) is a naturally high-quality insect protein resource, while its poor emulsification has limited its application in food industry. In order to change the present situation, in this research, the ultrasonic pretreatment (0 W, 200 W, 400 W, 600 W, and 800 W) method was used to improve the emulsification properties of CBTMP. Results indicated that ultrasound treatment especially at 400 W could significantly change the particle sizes, further increase the content of sulfhydryl group and surface hydrophobicity. The emulsification properties of emulsions were enhanced (from 4.16 ± 1.07 m2/g to 27.62 ± 2.20 m2/g) by sonicated CBTMP solution. Moreover, the physical stability of the emulsions to salt stress and centrifugation treatment was also promoted. Additionally, rheology revealed that a stronger network was formed at 400 W and all samples exhibited frequency-dependent and amplitude-dependent properties. The experiment demonstrated that ultrasound pretreatment was an effective means to improve the emulsification properties of CBTMP and it could provide a promising perspective for the application of CBTMP in food industry.


Assuntos
Ultrassom , Animais , Emulsões , Interações Hidrofóbicas e Hidrofílicas , Mariposas , Tamanho da Partícula , Reologia
15.
Food Sci Nutr ; 9(5): 2349-2363, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34026054

RESUMO

The health benefits and promising medical treatment potential of total flavonoids from Eupatorium lindleyanum DC. (TFELDC) have been recognized. The process parameters of extracting total flavonoids from Eupatorium lindleyanum DC. by ultrasonic-microwave synergistic extraction (UMSE) were optimized, and they were purified by AB-8 macroporous resin in the current study. In addition, the antioxidant and enzyme inhibitory activities of the purified TFELDC (PTFELDC) were evaluated. The results showed that the optimal parameters of UMSE were as follows: ethanol volume fraction 71.5%, L/S ratio 12.2 ml/g, microwave power 318 W, and extraction time 143 s. After TFELDC were purified by AB-8 macroporous resin, the total flavonoid contents of PTFELDC increased from 208.18 ± 1.60 to 511.19 ± 3.21 mg RE/g FDS. Compared with TFELDC, the content of total flavonoids in PTFELDC was increased by 2.46 times. The antioxidant activities of PTFELDC were assessed using DPPH radical, superoxide anion radical, reducing power, and ferric reducing antioxidant power assays, and the IC50 values were found to be 37.13, 19.62, 81.22, and 24.72 µg/ml, respectively. The enzyme inhibitory activities of PTFELDC were measured using lipase, α-amylase, α-glucosidase, and acetylcholinesterase assays with the IC50 values 1.38, 2.08, 1.63, and 0.58 mg/ml, respectively. By comparing with their positive controls, it was found that PTFELDC had good antioxidant activities, and lipase, α-amylase, and α-glucosidase inhibitory activities, However, the acetylcholinesterase inhibitory activity was relatively weaker. These results suggested that PTFELDC have a promising potential as natural antioxidant, antilipidemic, and hypoglycemic drugs used in functional foods or pharmaceuticals.

16.
J Food Sci ; 85(11): 3815-3822, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33063333

RESUMO

Herbaceous peony (HP) seed oil has been consumed in some regions of China, yet little information is available on its bioactive composition and antioxidant activity. This study aimed to evaluate the fatty acid compositions, micronutrients contents, and cellular antioxidant activity (CAA) of HP seed oil from five varieties. Results indicated that this oil had high percentages of monounsaturated (32.15 to 45.92%) and polyunsaturated fatty acids (58.65 to 61.95%), and the α-linolenic acid C18:3 was the highest in Fushao seed oil. Additionally, the high concentrations of tocopherol and phytosterol were found in all seed oils, and 10 individual polyphenols have been evaluated. Fushao seed oil had the highest polyphenols levels and showed higher CAA values. Both hierarchical cluster analysis and principal component analysis have been used to distinguish HP seed oil from different varieties. This information is valuable for the nutritional value and industrial interest of HP seed oil in China. PRACTICAL APPLICATION: This research showed that Herbaceous peony seed oil had higher levels of minor components and polyunsaturated fatty acids, especially, α-linolenic acid, and our results could also provide the theoretical foundation for the health benefits of Herbaceous peony seed oil as the vegetable oils. However, the variety of Herbaceous should be considered when extracting oil from Herbaceous peony seeds in the industry.


Assuntos
Antioxidantes/análise , Paeonia/química , Óleos de Plantas/análise , Sementes/química , China
17.
Int J Biol Macromol ; 160: 446-455, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32479940

RESUMO

In order to exploit an abundant and cheap carbon source for poly(3-hydroxybutyrate) (PHB) production, the rice husk was pretreated with dilute sulfuric acid and steam flash-explosion to enhance the enzymatic saccharification. The yield of reducing sugars of pretreated rice husk hydrolysate came up to 266.5 mg/g rice husk, much higher than that of untreated rice husk hydrolysate (72.67 mg/g rice husk). This result indicated that the pretreatment can significantly enhance the yield of reducing sugars. Then the hydrolysate was used as a sole carbon source for PHB production by using Cupriavidus necator. Response surface method was used to optimize the fermentation conditions. Under optimum fermentation conditions (carbon source, 31.81 gL-1; nitrogen source, 1.8 gL-1; pH-value, 7.0; temperature, 27.1 °C), the PHB yield was 5.0 gL-1, which was in good agreement with the predicted value.


Assuntos
Ácido 3-Hidroxibutírico/metabolismo , Hidroxibutiratos/metabolismo , Oryza/metabolismo , Poliésteres/metabolismo , Carbono/metabolismo , Cupriavidus necator/metabolismo , Explosões , Fermentação/fisiologia , Hidrólise , Vapor , Açúcares/metabolismo , Ácidos Sulfúricos/metabolismo
18.
Biotechnol Prog ; 36(4): e2992, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32185881

RESUMO

Alligator weed (Alternanthera philoxeroides) is a stoloniferous, amphibious and perennial herb which has invaded many parts of the world and led to serious environmental and ecological problems. In order to exploit cheap carbon source for poly(3-hydroxybutyrate) (PHB) production, alligator weed hydrolysates were prepared by acid and enzyme treatment and used for PHB production via Cupriavidus necator. The bacterium utilized alligator weed enzymatic hydrolysate and produced the PHB concentration of 3.8 ± 0.2 g/L at the conditions of pH 7.0, 27.5°C, 1.5 g/L of nitrogen source, and 25 g/L of carbon source, this exceeded the value of 2.1 ± 0.1 g/L from acid hydrolysate media at the same conditions. In order to obtain the optimum conditions of PHB production, response surface methodology was employed which improved PHB content. The optimum conditions for PHB production are as follows: carbon source, 34 g/L; nitrogen source, 2 g/L; pH, 7; temperature, 28°C. After 72 hr of incubation, the bacterium produced 8.5 g/L of dry cell weight and 4.8 g/L of PHB. The PHB was subjected to Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and Molecular weight analysis and found the melting temperature, number average molecular mass, and polydispersity were 168.20°C, 185 kDa, and 2.1, respectively.


Assuntos
Carbono/química , Cupriavidus necator/genética , Fermentação/genética , Hidroxibutiratos/química , Poliésteres/química , Amaranthaceae/química , Cupriavidus necator/química , Hidrolisados de Proteína/química
19.
Adv Mater ; 32(14): e1903759, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32078198

RESUMO

The efficacy of therapeutics for brain tumors is seriously hampered by multiple barriers to drug delivery, including severe destabilizing effects in the blood circulation, the blood-brain barrier/blood-brain tumor barrier (BBB/BBTB), and limited tumor uptake. Here, a sequential targeting in crosslinking (STICK) nanodelivery strategy is presented to circumvent these important physiological barriers to improve drug delivery to brain tumors. STICK nanoparticles (STICK-NPs) can sequentially target BBB/BBTB and brain tumor cells with surface maltobionic acid (MA) and 4-carboxyphenylboronic acid (CBA), respectively, and simultaneously enhance nanoparticle stability with pH-responsive crosslinkages formed by MA and CBA in situ. STICK-NPs exhibit prolonged circulation time (17-fold higher area under curve) than the free agent, allowing increased opportunities to transpass the BBB/BBTB via glucose-transporter-mediated transcytosis by MA. The tumor acidic environment then triggers the transformation of the STICK-NPs into smaller nanoparticles and reveals a secondary CBA targeting moiety for deep tumor penetration and enhanced uptake in tumor cells. STICK-NPs significantly inhibit tumor growth and prolong the survival time with limited toxicity in mice with aggressive and chemoresistant diffuse intrinsic pontine glioma. This formulation tackles multiple physiological barriers on-demand with a simple and smart STICK design. Therefore, these features allow STICK-NPs to unleash the potential of brain tumor therapeutics to improve their treatment efficacy.


Assuntos
Antineoplásicos/química , Barreira Hematoencefálica/metabolismo , Portadores de Fármacos/química , Nanopartículas/química , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Barreira Hematoencefálica/efeitos dos fármacos , Ácidos Borônicos/química , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Carbocianinas/química , Linhagem Celular Tumoral , Dissacarídeos/química , Gadolínio DTPA/química , Glioma/tratamento farmacológico , Glioma/mortalidade , Glioma/patologia , Humanos , Concentração de Íons de Hidrogênio , Estimativa de Kaplan-Meier , Camundongos , Camundongos Endogâmicos BALB C , Transcitose , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Food Sci Nutr ; 7(9): 3062-3070, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31572599

RESUMO

Seedpod, the nonedible portion of lotus (Nelumbo nucifera Gaertn.), was reported to be rich in polyphenols. The objective of this study was to investigate the major bioactive polyphenols of the lotus seedpods. The total polyphenol content (TPC) from ethanol extract of lotus seedpod (PELS) was found to be 34.23 µg gallic acid equivalents (GAE)/mg extract. Four polyphenolic compounds were identified in the PELS, comprised of one flavan-3-ol (catechin) and three flavonoids (kaemferol, quercetin and hyperoside). In vitro antioxidant and antiproliferative properties of the PELS were evaluated. PELS exhibited 89.38%, 99.82%, 68.25%, and 95.82% scavenging activities against 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide, hydroxyl, and 2,2'azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radicals, respectively, at 1.6 mg/ml. The Fe3+ reducing power of PELS was 0.605 at 0.32 mg/ml, which is comparable to glutathione (GSH). The PELS showed 31.79% metal chelating capacity and 87.79% inhibition of linoleic acid auto-oxidation at 1.6 mg/ml. PELS showed cytotoxicity toward HepG2 and LNcap cell lines in vitro with IC50 values at 44.59 and 11.50 µg/ml, respectively. The findings of this study provide evidences that the inedible lotus seedpod could be a source for natural antioxidants and anticancer agents.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA