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1.
J Tissue Viability ; 33(3): 362-375, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38906753

RESUMO

OBJECTIVE: Moisture-associated skin damage (MASD) is an inflammatory skin condition caused by long-term exposure to a moist environment, which can compromise the integrity of the barrier and increase pain. This scoping review aimed to systematically analyze the research status of prevention and care for MASD. METHODS: We conducted a scoping review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. PubMed, MEDLINE, Scopus, Web of Science, CINAHL, and the Cochrane Database of Systematic Reviews were searched for relevant articles until March 2023. RESULTS: Based on eligibility criteria, 34 research studies and review articles were included. The prevalence of MASD varies greatly in different medical environments and patient groups. The high-risk factors included prolonged exposure to excessive water, chemical irritation such as urine or feces, mechanical factors such as friction or improper removal of medical adhesives and local bacterial colonization. Prevention measures mainly include avoiding skin exposure to moisture, skin cleansing, moisturizing and the treatment of secondary bacterial infection. CONCLUSION: A variety of factors have an impact on MASD. Nurses should select suitable tools to screen high-risk patients and take targeted preventive measures according to the related types of skin injury to reduce the incidence of MASD.


Assuntos
Pele , Humanos , Pele/lesões
2.
Chem Biodivers ; 20(7): e202300169, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37382028

RESUMO

Natural antioxidants play an important role in promoting good health because of their prevention for oxidative damage. The work aimed to explore the antioxidant mechanism and activity of cannabidiol (CBD) at the cellular level. The human umbilical vein endothelial cell (HUVEC) with oxidative damage was employed as the model to study the protective capability of CBD. The results showed that CBD pre-treatment before the cells were exposed to hydrogen peroxide (H2 O2 ) resulted in an obvious increase of cell viability (about 100 %) and antioxidant related enzymes activity, and a decline of malondialdehyde (MDA) level. Besides, CBD could alleviate the increase of intracellular reactive oxygen species (ROS) content, the contraction of nucleus, and condensation of chromatin. The changes showed a dose-dependent effect. Additionally, the free radicals scavenging capacity of CBD was comparable to that of typical natural antioxidant, anthocyanidins. In summary, CBD could be employed as a potent antioxidant source for avoiding the oxidative damage. These results could provide the foundation for the development of CBD antioxidant products.


Assuntos
Antioxidantes , Canabidiol , Humanos , Células Endoteliais da Veia Umbilical Humana , Antioxidantes/farmacologia , Peróxido de Hidrogênio/toxicidade , Canabidiol/farmacologia , Superóxido Dismutase/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio , Apoptose
3.
J Org Chem ; 87(22): 15301-15311, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36321357

RESUMO

A novel protocol for the construction of highly functionalized indolizine derivatives, that is, 1H-pyrrolo[3,4-b]indolizine-1,3-diones (PIZDOs, 3) from 2-(pyridine-2-yl)acetates and maleimides via a regioselective oxidative [3 + 2] annulation was developed. The cascade oxidative reaction was enabled by heating a mixture of the two substrates in the presence of Ag2CO3 as an oxidant and Cu(OAc)·H2O as a catalyst in chlorobenzene. Consequently, a series of PIZDOs 3 were synthesized with high regioselectivity in moderate yields. This protocol can be used in the synthesis of functionalized PIZDOs via the one-pot oxidative annulation reaction rather than through multistep reactions, which is suitable for both combinatorial and parallel syntheses of PIZDOs.

4.
Molecules ; 27(20)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36296648

RESUMO

In this study, a green process of ß-cyclodextrin (ß-CD)-assisted extraction of active ingredients from Forsythia suspensa leaves was developed. Firstly, the optimal process of extraction was as follows: the ratio between Forsythia suspensa leaves and ß-CD was 3.61:5, the solid-liquid ratio was 1:36.3, the temperature was 75.25 °C and the pH was 3.94. The yields of forsythoside A, phillyrin and phillygenol were 11.80 ± 0.141%, 5.49 ± 0.078% and 0.319 ± 0.004%, respectively. Then, the structure characteristics of the ß-CD-assisted extract of Forsythia suspensa leaves (FSE-ß-CD) were analyzed using powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and molecular docking to demonstrate that the natural active products from Forsythia suspensa leaves had significant interactions with the ß-CD. Additionally, the loss of forsythoside A from aqueous FSE-CD at 80 °C was only 12%, compared with Forsythia suspensa leaf extract (FSE) which decreased by 13%. In addition, the aqueous solubility of FSE-CD was significantly increased to 70.2 g/L. The EC50 for scavenging DPPH and ABTS radicals decreased to 28.98 ug/mL and 25.54 ug/mL, respectively. The results showed that the ß-CD-assisted extraction process would be a promising technology for bioactive compounds extracted from plants.


Assuntos
Ciclodextrinas , Forsythia , beta-Ciclodextrinas , Forsythia/química , Espectroscopia de Infravermelho com Transformada de Fourier , Simulação de Acoplamento Molecular , Pós , Extratos Vegetais/química
5.
Molecules ; 27(18)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36144481

RESUMO

A large amount of hemp polysaccharides remain in industrial hemp residues (IHR) after cannabidiol extraction, resulting in the waste of resources. Therefore, the systematic study of hemp polysaccharides is beneficial to the development of IHR in the future. In this study, the extraction of industrial hemp residues polysaccharide (IHRPs) was optimized by single-factor experiment and orthogonal experimental design. The optimum heating extraction conditions were extraction temperature 98 °C, solid-liquid ratio 1:10, extraction time 1 h, number of successive extractions 2, and pH at 4. The extraction ratio and the polysaccharide content were 20.12 ± 0.55% and 12.35 ± 0.26% at the conditions, respectively. Besides, the best alcohol precipitation conditions were pumping with 2 L/h, stirring continuously, and ice-water bath for 4 h. The crude IHRPs was further purified by column chromatography and the polysaccharide/protein contents of purified IHRPs were 34.44% and 1.61%. IHRPs was mainly made up of ten monosaccharides and some non-sugar components including organic acids, flavonoids, steroids, and glycoside. The FT-IR demonstrated the polysaccharide skeleton of IHRPs. Moreover, the DPPH and ABTS scavenging rate of IHRPs were 76.00% and 99.05% at the concentrations of 1 mg/mL. IHRPs could promote the epidermal cells proliferation and healing of cell scratches. Meanwhile, IHRPs could promoted the expression of anti-aging-related genes. Overall, IHRPs could be a desirable natural source of antioxidants and anti-aging products in many aspects.


Assuntos
Canabidiol , Cannabis , Antioxidantes/química , Flavonoides , Glicosídeos , Gelo/análise , Monossacarídeos/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Molecules ; 25(17)2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32847017

RESUMO

Quinoa is known for its rich nutrients and bioactive compounds. In order to elucidate the preliminary structural characteristics and biological activity of polysaccharides from quinoa (QPs), five crude polysaccharides (QPE50, QPE60, QPE70, QPE80 and QPE90) were successively fractionated by gradient ethanol, and their physicochemical properties, antioxidant and antidiabetic activities were analyzed. The results implied that their total sugar contents were 52.82%, 63.69%, 67.15%, 44.56%, and 41.01%, and their weight-average molecular weights were 13,785 Da, 6489 Da, 4732 Da, 3318 Da, and 1960 Da, respectively. Glucose was a predominantly monosaccharide in these QPs, which together in QPE50, QPE60, QPE70, QPE80, and QPE90, respectively, made up 94.37%, 87.92%, 92.21%, 100%, and 100% of the total polysaccharide. Congo red test showed that all five QPs contained triple-helix structure. The Fourier transform-infrared spectroscopy (FT-IR) and X-ray diffractometry (XRD) results suggest that the QPs form a semi-crystalline polymer constituted typical functional groups of polysaccharide including CO, CH and OH. The thermogravimetric analysis (TGA) of QPs showed that weight loss was at about 200 °C and 320 °C. The observation from scanning electron microscope (SEM) and atomic force microscope (AFM) image indicated that the morphology of QPs exhibited spherical shape. Antioxidant and antidiabetic assay exhibited that all five QPs samples had certain antioxidant and antidiabetic activities, and QPE90 showed the best antioxidant and antidiabetic activity. Overall, QPs present a promising natural source of food antioxidants and antidiabetic agents.


Assuntos
Antioxidantes , Chenopodium quinoa/química , Hipoglicemiantes , Polissacarídeos , Sementes/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Polissacarídeos/química , Polissacarídeos/isolamento & purificação
7.
J Sep Sci ; 38(7): 1194-203, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25604674

RESUMO

An efficient ultrasound-assisted aqueous two-phase extraction and enrichment process for phenylethanoid glycosides from Cistanche deserticola Y. C. Ma stems was developed in this work. An ethanol/ammonium sulfate system was chosen for the aqueous two-phase system due to its fine partitioning and recycling behaviors. Single-factor experiments and response surface methodology were used to optimize the process parameters of the ultrasound-assisted aqueous two-phase extraction. The optimal conditions were as follows: a salt concentration of 23.5%, an ethanol concentration of 20%, an extraction time of 37 min, an extraction temperature of 30°C, a liquid/solid ratio of 30:1 w/w, and an ultrasound power of 300 W. Under the above conditions, the extraction yields of echinacoside and acteoside (the main components of phenylethanoid glycosides) reached 5.35 and 6.22 mg/g dry material weight, respectively. The contents of echinacoside and acteoside in the extracts reached 27.56 and 30.23 mg/g, respectively, which were 2.46- and 2.58-fold higher than the amounts obtained in ultrasound-assisted extraction. In conclusion, ultrasound-assisted aqueous two-phase extraction was an efficient, ecofriendly, and economical method, and it may be a promising technique for extracting and enriching bioactive components from plants.


Assuntos
Cistanche/química , Glicosídeos/isolamento & purificação , Extratos Vegetais/química , Caules de Planta/química , Ultrassom , Cromatografia Líquida de Alta Pressão , Temperatura , Água
8.
Int J Biol Macromol ; 263(Pt 1): 130294, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382790

RESUMO

Herein, three pretreated grapevine lignins were incorporated into carboxymethyl cellulose films. The effects of traditional NaOH pretreated lignin and DES (ChCl-LA, ChCl-LA & K2CO3-EG) pretreated lignin on film properties were compared. Modern analytical techniques were employed to systematically characterize the pretreated lignin and the different CMC-lignin films. The results showed that DES lignin was of high purity, low molecular weight, and homogeneous structure. It outperformed traditional NaOH lignin in terms of compatibility with CMC, enabling it to perform its bioactivity and physicochemical functions in films. This feature effectively enhanced the hydrophobicity, UV shielding ability, water vapor barrier, thermal stability, mechanical properties, and biological activity of CMC-DES lignin film. NMR (2D HSQC) showed that the excellent antioxidant and antibacterial capabilities of CMC-DES lignin film are due to the retention of butyl (S) and p-hydroxyphenyl (H) units in DES lignin, resulting in its rich phenolic hydroxyl content. The detailed structural elucidation of DES lignin's chemical interactions with CMC provided valuable insights into the advantageous properties observed in the films, presenting innovative solutions for applications in the food packaging and preservation industries.


Assuntos
Anti-Infecciosos , Lignina , Lignina/química , Carboximetilcelulose Sódica/química , Antioxidantes/farmacologia , Antioxidantes/química , Hidróxido de Sódio , Permeabilidade , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Embalagem de Alimentos
9.
Int J Biol Macromol ; 269(Pt 2): 132144, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729476

RESUMO

Herein, we investigated the synergistic effects of jet milling (JM) and deep eutectic solvent (DES) pretreatment on the fractionation of grapevine lignin and the consequent enhancement of enzymatic hydrolysis. Grapevine, a substantial byproduct of the wine industry, was subjected to JM pretreatment to produce finely powdered particles (median diameter D50 = 98.90), which were then further treated with acidic ChCl-LA and alkaline K2CO3-EG DESs. The results revealed that the combined JM + ChCl-LA pretreatment significantly increased the cellulose preservation under optimal conditions (110 °C, 4 h, and 20 % water content), achieving removal rates of 74.18 % xylan and 66.05 % lignin, respectively. The pretreatment temperature and inhibitor production were reduced, resulting in a remarkable threefold increase in glucose yield compared to untreated samples. Moreover, the structural analysis of the pretreated lignin indicated an enrichment of phenolic units, leading to enhanced antioxidant and antibacterial activities, particularly in the JM pretreated samples. These findings underscore the promising potential of the synergistic JM and DES pretreatment in facilitating the efficient utilization of grapevine lignocellulosic biomass for sustainable biorefinery technologies.


Assuntos
Solventes Eutéticos Profundos , Lignina , Vitis , Lignina/química , Vitis/química , Hidrólise , Solventes Eutéticos Profundos/química , Fracionamento Químico/métodos , Antioxidantes/química , Antioxidantes/farmacologia , Biomassa , Celulose/química , Celulase/química , Celulase/metabolismo , Solventes/química , Temperatura
10.
Int J Biol Macromol ; : 133525, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945317

RESUMO

To reduce environmental pollution and improve human health, developing green active food packaging materials is very necessary. In this study, a novel antioxidant and antibacterial composite film was produced by incorporating inclusion complex (CDIC) of cannabidiol (CBD) with 2,6-di-O-methyl-ß-cyclodextrin (DM-ß-CD) into pectin. The pectin films loaded with CBD and hemp leaf water extract (HLE) were prepared for comparison. Comprehensive characterizations showed CBD was encapsulated by DM-ß-CD and CDIC was evenly dispersed into pectin matrix, forming the compact and intact film. The composite films showed good mechanical properties and biodegradability. CDIC film showed the highest transparency and smoothness (Rrms/Rmax: 2.6/16.8 nm). The addition of bioactives reduced the water-binding capacity and CDIC film had the strongest hydrophobicity. Besides, DM-ß-CD encapsulation improved the thermal stability of CBD in CDIC film. Benefiting from encapsulation and excellent bioactivities of CBD, CDIC film showed excellent antioxidant capacity and antibacterial activity, effectively inhibiting colony growth and maintaining the strawberry color in strawberry preservation. This work could provide a novel eco-friendly candidate for food packaging material and expand the use of CBD in food industry.

11.
Int J Biol Macromol ; 236: 123977, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36906200

RESUMO

Deep eutectic solvents (DESs) have been extensively applied to pretreat lignocellulose; however, comparative research on acidic and alkaline DES pretreatment is relatively lacking. Herein, pretreatment of grapevine agricultural by-products with seven DESs were compared in terms of removal of lignin and hemicellulose and component analysis of the pretreated residues. Among the tested DESs, both acidic choline chloride-lactic (CHCl-LA), and alkaline potassium carbonate-ethylene glycol (K2CO3-EG) were effective in delignification. Thereafter, the CHCl-LA and K2CO3-EG extracted lignin was compared by analyzing their physicochemical structure changes and antioxidant properties. The results showed that the thermal stability, molecular weight, and phenol hydroxyl percentage of CHCl-LA lignin were inferior to K2CO3-EG lignin. It was found that the high antioxidant activity of K2CO3-EG lignin was mainly attributed to the abundant phenol hydroxyl, guaiacyl (G), and para-hydroxy-phenyl (H). By comparing acidic and alkaline DES pretreatments and their lignin nuances in biorefining, novel insights are derived for the scheduling and selection of DES for lignocellulosic pretreatment.


Assuntos
Antioxidantes , Lignina , Lignina/química , Antioxidantes/farmacologia , Solventes Eutéticos Profundos , Solventes/química , Biomassa , Colina/química , Fenóis , Hidrólise
12.
Food Res Int ; 168: 112783, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37120229

RESUMO

Jet milling is a common technique in ultrafine powder preparation field. It has never been used to design delivery systems. Cannabidiol (CBD) is an important cannabinoid of hemp but poor aqueous solubility limited its applications. In this study, solid dispersion (SD) technique was combined with cyclodextrin complexation technique, and jet milling was used for the first time to prepare SDs for improving CBD solubility. Different characterizations demonstrated that the dispersion effect and complexation structure of CBD SD3 prepared by jet milling were comparable to that of CBD SD2 prepared by spray drying (a common solution-based method), and were better than that of CBD SD1 prepared by cogrinding. The water solubility of CBD was increased to 20.902 µg/mL (909-fold) in CBD SD3. Besides, the antioxidant activity and cytotoxicity to tumor cells of CBD were enhanced by dispersion. This work indicated that jet milling, as a new technique with low cost and excellent applicability, could be further developed for the delivery of food functional factors or bioactive molecules.


Assuntos
Canabidiol , Canabidiol/química , Solubilidade , Água/química , Pós/química
13.
Int J Biol Macromol ; 247: 125761, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37429341

RESUMO

Herein, DES lignin was obtained by pretreatment of grapevine with a deep eutectic solvent (ChCl-LA). A novel chitosan-DES lignin composite aerogel material (CS-LIG aerogel) was prepared to adsorb methylene blue (MB), Congo red (CR), catechin (C), and epicatechin (EC). The CS-LIG aerogel was systematically characterized by modern technological instruments. It was demonstrated that the DES lignin was successfully incorporated and had an important effect on the morphological structure and adsorption of dyes and natural products in the aerogel. The adsorption kinetic models for both adsorbed CR and MB are pseudo-second-order models. Adsorption isotherms followed Langmuir for the adsorption of CR and Freundlich for the adsorption of MB. The π-π interaction and hydrogen bonding of DES lignin aromatic groups in CS-LIG aerogels were responsible for the adsorption of C and EC with 86.42 % and 90.85 % removal rates, respectively. This study opens a new avenue for the high-value utilization of DES lignin and the preparation of chitosan-based composites for the adsorption of dyes and purification of natural products.


Assuntos
Catequina , Quitosana , Poluentes Químicos da Água , Corantes/química , Lignina/química , Quitosana/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Vermelho Congo , Azul de Metileno/química , Poluentes Químicos da Água/química
14.
Int J Biol Macromol ; 245: 125507, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37355072

RESUMO

In this study, five polysaccharides were extracted from processed Cistanche deserticola. The processing included crude product, enzymatic hydrolysis, hot air drying, stir-baking with wine and high-pressure steaming, and these polysaccharides were named as CP-CDPs, EH-CDPs, HAD-CDPs, SBW-CDPs and HPS-CDPs, respectively. The structural characteristics and biological activities were explored. The results showed that processing changed properties of C. deserticola polysaccharides. CP-CDPs had the highest brightness value L*(93.84) and carbohydrate content (61.27 %). EH-CDPs had minimum Mw (1531.50 kDa), while SBW-CDPs had maximum Mw (2526.0 kDa). Glucose was major predominant monosaccharide in CP-CDPs (89.82 %), HAD-CDPs (79.3 %), SBW-CDPs (59.41 %) and HPS-CDPs (63.86 %), while galactose was major monosaccharide in EH-CDPs (29.44 %). According to SEM, SBW-CDPs showed compact structures, while HPS-CDPs and HAD-CDPs had similar looser structure than SBW-CDPs; meanwhile, CP-CDPs showed irregular agglomeration shape and EH-CDPs was dense blocky shape. The AFM showed SBW-CDPs had the largest molecular chain than other polysaccharides. When scavenging activity reaching 50 %, the concentrations of CP-CDPs, EH-CDPs, HAD-CDPs, SBW-CDPs, HPS-CDPs are 2.25, 0.25, 0.75, 1.8 and 1.5 mg/mL, respectively. This study sheds light on the effects of traditional Chinese medicine processing on characteristics, bioactivities of C. deserticola polysaccharides, and provides the basis for applications in food and pharmaceutical industries.


Assuntos
Antioxidantes , Cistanche , Antioxidantes/farmacologia , Antioxidantes/química , Cistanche/química , Extratos Vegetais/química , Vapor , Polissacarídeos/farmacologia , Polissacarídeos/química
15.
Food Chem ; 389: 132931, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-35500405

RESUMO

The purity of soy lecithin exerts significant impact on nanoliposome (NL) properties for food applications. In this study, three soy lecithin of different purity were used to prepare NL. LC-MS analysis confirmed soy lecithin of relatively low purify (50% and 70%) contains multiple natural phospholipids. NL produced by soy lecithin of middle purity (70%) is smaller and more stable than other counterparts. Ultimately, soy lecithin of 70% purity was selected to develop NL encapsulated crocetin (CR) as model payload and further coated by chitosan (CS). The structure characteristic, physicochemical properties, antioxidant activity and anti-inflammatory activity of crocetin nanoliposome (CR-NL) and chitosan coated crocetin nanoliposome (CS-CR-NL) were evaluated. NL encapsulation and CS coating significantly improve antioxidant and anti-inflammatory ability of CR, and prolong storage period of CR (p < 0.05). For food applications, soy lecithin of middle purity (70%) is cheaper and more appropriate than soy lecithin of high purity.


Assuntos
Quitosana , Lecitinas , Alérgenos , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Quitosana/química , Lecitinas/química
17.
Int J Biol Macromol ; 193(Pt B): 1635-1644, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34743027

RESUMO

In this paper, membrane separation technology was employed to separate polysaccharide fractions from the water extract of quinoa seeds. The chemical composition, structure characteristic and morphology were analyzed by chemical methods and instrumental analysis including HPLC-DAD, UV, FT-IR, Congo red test, SEM, AFM, XRD, TGA and NMR. Results indicated that three polysaccharide fractions named as QPs-I, QPs-II and QPs-III were successfully separated using microfiltration and ultrafiltration membrane with MWCO of 300 and 10 kDa in sequence. The Mw and polysaccharide content of three fractions were QPs-I (4609 Da, 33.75%), QPs-II (15,932 Da, 45.31%) and QPs-III (960,895 Da, 34.65%), respectively. The polysaccharide in three fractions was heteropolysaccharide that mainly consisted of glucose, galactose and arabinose, with their combined monosaccharide percentage being 91.17% in QPs-I, 87.81% in QPs-II, and 91.72% in QPs-III, respectively. All three polysaccharide fractions contained triple-helix structure. Biological experiment showed that antioxidant and antidiabetic activities in dose-dependent manners and also revealed immunoregulatory activity on RAW264.7 cells. These results indicated that QPs has the potential to be used in a natural agent in antioxidant, antidiabetic and immunoregulation functional food.


Assuntos
Chenopodium quinoa/química , Polissacarídeos/química , Sementes/química , Animais , Antioxidantes/química , Linhagem Celular , Glucose/química , Hipoglicemiantes/química , Camundongos , Monossacarídeos/química , Células RAW 264.7
18.
J Agric Food Chem ; 68(4): 1101-1109, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31904947

RESUMO

ε-Poly-l-lysine (ε-PL) consists of 25-35 lysine residues which are linked by an isopeptide bond formed by dehydration condensation of α-carboxyl and ε-amino groups and has good antibacterial activity and broad-spectrum inhibition range. However, there is no clear conclusion about the structure and antibacterial mechanism of ε-PL in aqueous solution. Herein, a high purity of ε-PL was prepared using Amberlite IRC-50 ion-exchange resin. Membrane filtration and dynamic light scattering were used to study the variations of ε-PL aggregation in aqueous solution with pH value. The conformational changes and antibacterial activities of ε-PL and carbamoylated ε-PL in different water environments were studied with circular dichroism (CD) and inhibition zone. The structural changes during the spray-drying process were determined by Fourier transform infrared spectroscopy. The results indicated that the side chain amino charge played a decisive role in the ε-PL conformation and aggregation. ε-PL exhibited the properties of a ß-sheet during spray drying from acidic liquids to solids. The cation enhanced the antibacterial activity of ε-PL but did not play a key role. Instead, the backbone of ε-PL might determine the mechanism of ε-PL antibacterial.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Polilisina/química , Polilisina/farmacologia , Antibacterianos/metabolismo , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Transição de Fase , Polilisina/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Streptomyces/química , Streptomyces/metabolismo
19.
J Food Sci ; 83(4): 966-974, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29524221

RESUMO

A novel technique of ultrasound-assisted freeze-thaw pretreatment (UFP) was developed to improve the drying efficiency of maca and bioactive amide synthesis in maca. The optimal UFP conditions are ultrasonic processing 90 min at 30 °C with 6 freeze-thaw cycles. Samples with freeze-thaw pretreatment (FP), ultrasound pretreatment (UP), and UFP were prepared for further comparative study. A no pretreatment (NP) sample was included as a control. The results showed that UFP improved the drying efficiency of maca slices, showing the highest effective moisture diffusivity (1.75 × 10-9 m2 /s). This result was further supported by low-field nuclear magnetic resonance (LF-NMR) analysis and scanning electron microscopy (SEM). The rehydration capacity and protein content of maca slices were improved by UFP. More importantly, contents of bioactive macamides and their biosynthetic precursors were increased in 2.5- and 10-fold, respectively. In conclusion, UFP is an efficient technique to improve drying efficiency, physicochemical properties, and bioactive macamides of maca, which can be applied in the industrial manufacture of maca products.


Assuntos
Manipulação de Alimentos/métodos , Lepidium/química , Preparações de Plantas/química , Proteínas Alimentares/análise , Congelamento , Humanos , Extratos Vegetais/biossíntese , Ondas Ultrassônicas , Água
20.
J Ethnopharmacol ; 208: 1-7, 2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28647510

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Gan Kang Yuan (GKY) is a compound medicine formulated on the basis of traditional Chinese medicine (TCM). It was composed of Herba Cistanchis (Roucongrong), Radix Puerariae (Gegen), Radix Astragali (Huangqi), Fructus Schisandrae (Wuweizi) and Radix Glycyrrhizae (Gancao). AIM: The purpose of this study is to research the hepatoprotective effect of GKY against liver injury induced by alcohol, and to elucidate the mechanism of hepatopretective effect. MATERIALS AND METHODS: Hepatoprotective activity of GKY was researched both in vivo and vitro. In vitro, effect of GKY on the survival rates of HepG2 cells were assessed. In vivo research, ICR mice were oral administrated with alcohol (Er Guo-tou white spirit, 56%, 6mL/kg, once per day) for 31 days to establish liver injury model. Meanwhile, positive group or experimental groups were treated with bicyclol (300mg/kg) or GKY (200, 600, 1800mg/kg). Serological indexes including aspartate and alanine transaminases (AST, ALT), γ-glutamyl transpeptidase (γ-GTP), total bilirubin (TBil), total cholesterol (TCHO) and serum triglyceride (STG) were estimated. Hepatic indicators including superoxide dismutase (SOD), glutathione S-transferase (GST), glutathione (GSH), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), and liver triglyceride (LTG) were analyzed. Histopathologic changes of liver tissue were observed. RESULTS: The survival rates of HepG2 cell were observably promoted by GKY. Alcoholic treatment drastically altered the serum indexes and liver indicators of model animals, while these alteration were significantly ameliorated by GKY (p < 0.05, 0.01 or 0.001) in experimental group. The microvesicular steatosis and necrosis in hepatic histopathology induced by alcoholic treatment also were notably attenuated by GKY administration. CONCLUSIONS: These findings indicated that GKY possessed hepatoprotective property against liver injury induced by ethanol. GKY significantly promoted activities of relative enzymes and suppressed the contents of MDA and LTG, which might be the mechanism of hepatoprotective effect of GKY.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Etanol/efeitos adversos , Substâncias Protetoras/uso terapêutico , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Sobrevivência Celular/efeitos dos fármacos , Doença Hepática Crônica Induzida por Substâncias e Drogas/patologia , Colesterol/sangue , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Células Hep G2 , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Malondialdeído/metabolismo , Camundongos Endogâmicos ICR , Fitoterapia , Substâncias Protetoras/farmacologia , Superóxido Dismutase/metabolismo , Triglicerídeos/sangue , gama-Glutamiltransferase/sangue
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