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1.
Crit Rev Food Sci Nutr ; 58(14): 2416-2431, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28609145

RESUMO

In recent years, a big trend has been the development of rapid, green, efficient, economical, and scalable approaches for the separation and purification of bioactive molecules from natural sources, which can be used in food, cosmetics, and medicine. As a new nonchromatographic bioseparation technology, three-phase partitioning (TPP) is attracting the attention of a growing number of scientists and engineers. Although a number of studies have been published in the last 40 years regarding the extraction, separation, and purification of numerous bioactive molecules using TPP systems, a background review on TPP partitioning fundamentals and its applications is much needed. Therefore, the present review focuses in detail on the TPP separation process, including the definition of TPP, partitioning mechanisms, parameters for establishing the suitable condition to form precipitate such as concentration of ammonium sulfate, content of tert-butanol, pH and temperature, and the application for separation and purification of protein, enzyme, plant oil, polysaccharide, and other small molecule organic compounds. In addition, the possible directions of future developments in TPP technology are discussed. The review presents a good opportunity, as well as a challenge for scientists, to understand the detailed partitioning rule and to take better use of TPP for the production and separation of various bioactive molecules, which have been intensively applied in the food and medical fields.


Assuntos
Fracionamento Químico/métodos , Alimento Funcional/análise , Concentração de Íons de Hidrogênio , Micro-Ondas , Temperatura , Ultrassom
2.
Crit Rev Food Sci Nutr ; 57(6): 1256-1269, 2017 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-26506312

RESUMO

Edible and medicinal fungi (mushrooms) are widely applied to functional foods and nutraceutical products because of their proven nutritive and medicinal properties. Phellinus sensu lato is a well-known medicinal mushroom that has long been used in preventing ailments, including gastroenteric dysfunction, diarrhea, hemorrhage, and cancers, in oriental countries, particularly in China, Japan, and Korea. Polysaccharides represent a major class of bioactive molecules in Phellinus s. l., which have notable antitumor, immunomodulatory, and medicinal properties. Polysaccharides that were isolated from fruiting bodies, cultured mycelia, and filtrates of Phellinus s. l. have not only activated different immune responses of the host organism but have also directly suppressed tumor growth and metastasis. Studies suggest that polysaccharides from Phellinus s. l. are promising alternative anticancer agents or synergizers for existing antitumor drugs. This review summarizes the recent development of polysaccharides from Phellinus s. l., including polysaccharide production, extraction and isolation methods, chemical structure, antitumor activities, and mechanisms of action.


Assuntos
Antineoplásicos/química , Basidiomycota/química , Polissacarídeos/química , Agaricales/química , Animais , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Fenômenos Químicos , China , Modelos Animais de Doenças , Humanos , Imunomodulação , Japão , Neoplasias/tratamento farmacológico , Polissacarídeos/isolamento & purificação , República da Coreia
3.
Huan Jing Ke Xue ; 41(2): 620-629, 2020 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608720

RESUMO

Temporal evolution of black carbon (BC) in Nanjing was studied along with its main influencing factors. The multi-wavelength aethalometer (AE-33) was used to select the typical month of each season to observe BC mass concentration, combined with atmospheric pollutant data, meteorological elements, and boundary layer detection data. Seasonal, daily, weekly trends, and source characteristics of BC were analyzed. The results showed that the BC concentration in Nanjing had obvious seasonal changes, which were higher in spring and winter, in the decreasing order:spring[(3351±919) ng·m-3] > winter[(3234±2102) ng·m-3] > in autumn[(3064±967) ng·m-3] > summer[(2632±1705) ng·m-3]. The diurnal changes in BC during the four seasons are bimodal, with peaks at 06:00-08:00 and 21:00-23:00. The morning and evening peak distribution characteristics of BC in different seasons are different. The peak concentration of BC was highest in the early morning peak spring and the highest in the late peak winter. The morning peak timing of winter is 2 h behind other seasons, while the summer peak timing is 2 h ahead of other seasons. The effect of the wind speed on the seasonal distribution of BC diurnal variation is significantly larger than that on RH. The mechanism of the influence of the inversion layer on the concentration of atmospheric pollutants is complicated. The effects of height, thickness, and temperature of the inversion layer on the pollutants are different in different seasons. Weekly BC effects vary seasonally. The effect of RH and wind speed on the weekly BC effect is small, and the difference in the inversion layer is the main reason behind it. Liquid fuel combustion in Nanjing has a greater contribution to BC, whereas solid combustion contributes by a lesser extent.

4.
Huan Jing Ke Xue ; 40(12): 5213-5223, 2019 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854591

RESUMO

To explore the variation in characteristics of atmospheric pollutants at different stages of haze, the monitor for aerosols and gases in ambient air (MARGA) was used to observe the concentrations of precursor pollutants (NH3, HNO3, and SO2) and eight water-soluble ions in a regional haze in the Yangtze River Delta region from November 18 to December 07, 2018. Combined with environmental data (PM2.5, NO2, CO, and O3) and meteorological data, the causes of regional haze formation, diurnal variation characteristics of air pollutants, and distribution characteristics of air pollutants in different stages of haze were analyzed. The results showed that the Yangtze River Delta region was mainly controlled by a ridge of high pressure during the haze process and the weather situation was stable, which was conducive to the accumulation of air pollutants. On hazy days, the concentrations of PM2.5, NO2, NO3-, SO42-, NH4+, Cl-, and Na+ were (118.91±39.23), (61.62±26.34), (45.64±16.01), (18.80±8.02), (20.82±7.16), (3.02±2.25), and (0.23±0.22) µg·m-3, respectively, and these were 2.73, 1.63, 2.64, 1.94, 2.50, 2.05, and 2.56 times the levels found on clean days, respectively. The concentration of CO was (1.34±0.39) mg·m-3 on hazy days, which was 1.86 times that found on clean days. Diurnal variation characteristics of different air pollutants were different, as were the distribution characteristics of air pollutants at different haze stages. The concentrations of SO2 was the highest in the haze occurrence stage. The concentrations of PM2.5, NO2, NH3, CO, and SNA were highest in the haze development stage, and the concentrations of O3, Cl-, Na+, and K+ were highest in the haze dissipation stage. The relative contributions of SNA to PM2.5 in different stages of haze could reach 94%-96%, and their growth rate was largest in the development stage. The order of growth rate was NO3- > NH4+ > SO42-. SNA mainly existed in the form of NH4NO3 on clean days and in the occurrence and development stages, and (NH4)2SO4 in the dissipation stage. This haze process was mainly caused by the growth of NO3-, which was mainly generated by gas-phase homogeneous phase reaction, and NO3-contributes 51.06%, 51.85%, and 48.22%, respectively, to PM2.5 in the occurrence, development, and dissipation stages of haze.

5.
Ultrason Sonochem ; 40(Pt A): 128-134, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28946406

RESUMO

Ultrasound and three-phase partitioning (USTPP) were combined to extract and separate polysaccharides (PS) efficiently from Corbicula fluminea crude extracts. The following optimum experimental conditions were established: 20% (w/v) ammonium sulfate concentration, 1:1 (v/v) t-butanol to crude extract ratio, 180W ultrasonic power, 40kHz frequency, 100% duty cycle, 10min irradiation time, and 35°C. The maximum extraction yield of PS obtained from USTPP was approximately 11.22%, which was higher than the maximum yields from conventional three-phase partitioning (TPP; 9.32%) and ultrasound extraction (USE; 6.05%). The extraction time for USTPP was significantly reduced to 10min from 30 and 60min for TPP and USE methods, respectively. The primary chemical structures of PS collected through the three extraction protocols were basically conserved. The synergistic effects of ultrasound and TPP on PS extraction were also determined. Results revealed that USTPP is an effective technique to extract and separate PS from C. fluminea potentially applied in food, cosmetics, and medicines.


Assuntos
Fracionamento Químico/métodos , Corbicula/química , Polissacarídeos/isolamento & purificação , Ondas Ultrassônicas , Sulfato de Amônio/química , Animais , Polissacarídeos/química , Temperatura , Fatores de Tempo , terc-Butil Álcool/química
6.
Zhongguo Gu Shang ; 31(3): 281-285, 2018 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-29600684

RESUMO

Chondral injuries are short of self-healing ability and need to surgical repair after articular cartilage injury. Conventional treatment includes debridement and drainage under arthroscope, micro-fracture, osteochondral autograft transplantation (OATS), mosaiplasty and osteochondral allografts (OCA), autologous chondrocyte implantation (ACI). Debridement and drainage could remove pain factor, and has advantages of simple operation, wide clinical application and early clinical effect. Micro-fracture and osteochondral autograft transplantation is suitable for small area of cartilage repair, while the further effect showed that fibrous cartilage permeated by drill could decrease postoperative clinical effect. Osteochondral autograft transplantation has better advantages for reconstruction complete of wear-bearing joint. Autologous chondrocyte implantation and allogeneic cartilage transplantation are suitable for large area of cartilage defect, postoperative survival of allogeneic cartilage transplantation is effected by local rejection reaction and decrease further clinical effect. Cartilage tissue engineering technology could improve repair quality of autologous chondrocyte implantation, and make repair tissue close to transparent cartilage, but has limit to combined subchondral bone plate, reactive bone edema, bone loss and bad axis of lower limb. New technology is applied to cartilage injury, and has advantages of less trauma, simple operation, rapid recover, good clinical effect and less cost;and could be main method for treat cartilage injury with surgical repair technology. How to improve repair quality with compression resistance and abrasive resistance are expected to be solved.


Assuntos
Cartilagem Articular/lesões , Cartilagem Articular/cirurgia , Condrócitos/transplante , Traumatismos do Joelho/cirurgia , Articulação do Joelho/cirurgia , Humanos , Transplante Autólogo
7.
Medicine (Baltimore) ; 97(41): e12535, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30313040

RESUMO

BACKGROUND: To assess the safety and efficacy of percutaneous short-segment pedicle instrumentation compared with conventionally open short-segment pedicle instrumentation and provide recommendations for using these procedures to treat thoracolumbar fractures. METHODS: The Medline database, Cochrane database of Systematic Reviews, Cochrane Clinical Trial Register, and Embase were searched for articles published. The randomized controlled trials (RCTs) and non-RCTs that compared percutaneous short-segment pedicle instrumentation to open short-segment pedicle instrumentation and provided data on safety and clinical effects were included. Demographic characteristics, clinical outcomes, radiological outcomes, and adverse events were manually extracted from all of the selected studies. Methodological quality of included studies using Methodological Index for Non-Randomized Studies scale and Cochrane collaboration's tool for assessing the risk of bias by 2 reviewers independently. RESULTS: Nine studies encompassing 433 patients met the inclusion criteria. Subgroup meta-analyses were performed according to the study design. The pooled results showed there were significant differences between the 2 techniques in short- and long-term visual analog scale, intraoperative blood loss, operative time, postoperative draining loss, hospital stay, and incision size, although there were no significant differences in postoperative radiological outcomes, Oswestry Disability Index, hospitalization cost, intraoperative fluoroscopy time, and adverse events. CONCLUSION: Percutaneous short-segment pedicle instrumentation in cases with achieve satisfactory results, could replace in many cases extensive open surgery and not increased related complications. However, further high-quality RCTs are needed to assess the long-term outcome of patients between 2 techniques.


Assuntos
Fixação Interna de Fraturas/métodos , Vértebras Lombares/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Parafusos Pediculares , Fraturas da Coluna Vertebral/cirurgia , Vértebras Torácicas/cirurgia , Perda Sanguínea Cirúrgica , Ensaios Clínicos como Assunto , Humanos , Tempo de Internação , Duração da Cirurgia , Medição da Dor
8.
Ultrason Sonochem ; 29: 251-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26585005

RESUMO

In this study, a high-molecular-weight polysaccharide PL-N isolated from the alkaline extract of Phellinus linteus mycelia was degraded by ultrasound. Results showed that ultrasound treatment at different ultrasonic intensities decreased the intrinsic viscosity and molecular weight of PL-N, as well as narrowed the molecular weight distribution. A larger reduction in intrinsic viscosity and molecular weight was caused by a higher ultrasonic intensity. The degradation kinetics model was fitted to (1/Mt-1/M0)=k·t, and the reaction rate constant (k) increased with increasing ultrasonic intensity. Ultrasound degradation did not change the primary structure of PL-N, and scanning electron microscopy analysis indicated that the morphology of the original PL-N was different from that of degraded PL-N fractions. Antioxidant activity assays in vitro indicated that the degraded PL-N fraction with low molecular weight had stronger hydroxyl radical scavenging capacity and higher TEAC and FRAP values.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Basidiomycota/química , Micélio/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Ondas Ultrassônicas , Antioxidantes/isolamento & purificação , Cinética , Peso Molecular , Polimerização , Polissacarídeos/isolamento & purificação , Viscosidade
9.
Int J Biol Macromol ; 91: 92-9, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27212213

RESUMO

In this paper, the novel polysaccharide PL-A11 was purified from an ammonium oxalate extract of Phellinus linteus mycelia. Its physicochemical properties, structural characteristics, and antioxidant activities were investigated. Results showed that PL-A11 had a weight-average molecular weight (Mw) of 13.8kDa and was mainly composed of arabinose, xylose, mannose, and glucose in a molar ratio of 1.1:1.3:1.0:6.6. The backbone of PL-A11 was composed of (1→4)-α-d-glucopyranosyl, (1→2)-α-d-xylopyranosyl, and (1→3)-α-d-arabinofuranosyl residues, whereas the (1→6)-α-d-mannopyranosyl residues formed branches at the O-2 position with 1-linked-α-d-glucopyranosyl terminal residues. From the antioxidative activity tests in vivo, the administration of PL-A11 obviously enhanced the activity of antioxidant enzymes and significantly reduced the level of malondiadehyde (MDA) in the serum and liver of d-galactose-treated aging mice in a dose-dependent manner, as well as effectively stimulated the immune system of aging mice. These findings implied that PL-A11 could be developed as a potential antioxidant for applications in the functional food, pharmaceutical, cosmetic or nutraceutical industries.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Ácido Oxálico/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Envelhecimento/metabolismo , Animais , Antioxidantes/isolamento & purificação , Feminino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Peso Molecular , Monossacarídeos/análise , Phellinus , Extratos Vegetais/isolamento & purificação , Polissacarídeos/isolamento & purificação , Relação Estrutura-Atividade , Vísceras/efeitos dos fármacos , Vísceras/metabolismo
10.
Zhongguo Zhong Yao Za Zhi ; 30(18): 1443-7, 2005 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-16381468

RESUMO

OBJECTIVE: To optimize Supper Critical CO2 extracting technical (SFE-CO2) methods for extraction of anti-cancer active components of Fig Residues and to investigate the anti-cancer effect of the extract in vitro and in vivo. METHOD: The anti-cancer activity of extracted compound was measured on U937,95D and AGS cancer cells in vitro by MTT method. The anti-cancer effect of the extraction of Fig Residues was studied on mice transplant liver cancer in vivo. RESULT: The SFE-CO2 condition for extraction of the anti-cancer components of Fig Residues was optimized as follows: granularity was 100, the extraction pressure was 30 MPa, the extraction temperature was 45 degrees C, the extraction time was 6 h and the CO2 flux was 12 L x h(-1); The IC50 of anti-cancer active components of Fig Residues on U937, 95D and AGS cells were 70.125 microg x mL(-1), 127.957 microg x mL(-1), 116.000 microg x mL(-1); The anti-cancer active components of Fig Residues inhibited 49.3% of the transplanted liver cancer in the mice. CONCLUSION: The method for extracting the anticancer active components of Fig Residues is stable and reasonable, and the extract from Fig Residues is of the anticancer effect.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Ficus , Neoplasias Hepáticas/patologia , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cromatografia com Fluido Supercrítico/métodos , Medicamentos de Ervas Chinesas/isolamento & purificação , Feminino , Ficus/química , Frutas/química , Humanos , Concentração Inibidora 50 , Masculino , Camundongos , Transplante de Neoplasias , Plantas Medicinais/química , Neoplasias Gástricas/patologia , Células U937/efeitos dos fármacos
11.
Carbohydr Polym ; 115: 472-7, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25439921

RESUMO

A novel high molecular weight polysaccharide (PL-N1) was isolated from alkaline extract of the cultured Phellinus linteus mycelia. The weight average molecular weight (Mw) of PL-N1 was estimated at 343,000kDa. PL-N1 comprised arabinose, xylose, glucose, and galactose in the molar ratio of 4.0:6.7:1.3:1.0. The chemical structure of PL-N1 was investigated by FTIR and NMR spectroscopies and methylation analysis. The results showed that the backbone of PL-N1 comprised (1→4)-linked ß-D-xylopyranosyl residues, (1→2)-linked α-D-xylopyranosyl residues, (1→4)-linked α-D-glucopyranosyl residues, (1→5)-linked ß-D-arabinofuranosyl residues, (1→4)-linked ß-D-xylopyranosyl residues which branched at O-2, and (1→4)-linked ß-D-galactopyranosyl residues which branched at O-6. The branches consisted of (1→)-linked α-D-arabinofuranosyl residues. Antitumor activity assay in vitro showed that PL-N1 could inhibit the growth of HepG2 cells to a certain extent in a dose-dependent manner. Thus, PL-N1 may be developed as a potential, natural antitumor agent and functional food.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Linhagem Celular Tumoral , Humanos , Concentração de Íons de Hidrogênio , Peso Molecular , Phellinus , Extratos Vegetais , Relação Estrutura-Atividade
12.
Carbohydr Polym ; 121: 64-70, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25659672

RESUMO

In this study, high-intensity ultrasound (20 kHz), a simple, effective and without any additive method, was used to the degradation of carboxylic curdlan (Cc) produced by 4-acetamido-TEMPO-mediated oxidation. The effects of ultrasound on molecular properties, structure and chain conformations of Cc were investigated by viscometry, size-exclusion chromatography with multiangle laser-light scattering (SEC-MALLS) analysis, as well as FTIR and NMR spectroscopies. The results indicated that the intrinsic viscosity [η] and the weight-average molecular weight (Mw) of Cc decreased obviously after ultrasound, and a uniform and narrow distribution of degradation product was obtained. The z-average radius of gyrations (Rg) firstly increased and then decreased as the sonication time prolonged. Ultrasound destroyed the hydrogen bonds resulting in the transition from compact random coil conformation to more flexible and even shorter extended chains. Ultrasonic treatment could not alter the primary chemical structure of Cc molecules according to the structural analysis by FTIR and NMR spectroscopies. Degradation kinetics based on Schmid model was applied to estimate the degradation rate constant k. It was found that the k value of Cc decreased with increasing the polymer concentration from 0.05 to 0.2% (w/v).


Assuntos
Sonicação , beta-Glucanas/química , Configuração de Carboidratos , Óxidos N-Cíclicos/química , Cinética , Peso Molecular , Oxirredução , Viscosidade
13.
Int J Biol Macromol ; 72: 333-40, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25193095

RESUMO

In this study, a new non-toxic, biodegradable, biocompatible and water-soluble carboxylic curdlan bearing the dissociable COOH group in 100% purity, which was prepared by 4-acetamido-TEMPO-mediated oxidation, was hydrophobically modified by deoxycholic acid (DOCA) to attain novel amphiphilic curdlan derivatives (CCDs) for the preparation of nano-carriers for antitumor drug doxorubicin (DOX). Under the effect of ultrasonication, the carboxylic curdlan derivatives in water were self-aggregated into spherical nanoparticles with diameters ranging from 214 nm to 380 nm. The critical aggregation concentrations decreased from 0.047 mg/mL to 0.016 mg/mL with increasing DS of DOCA. DOX-loaded CCD nanoparticles were prepared in an aqueous medium with dialysis method. The DOX-CCD nanoparticles exhibited pH- and dose-dependent drug release profiles during in vitro release experiments. Moreover, the drug transport mechanism was Fickian diffusion according to the Ritger-Peppas model. The CCD nanoparticles might be explored as potential carriers for hydrophobic drugs with controlled release and delivery functions.


Assuntos
Ácido Desoxicólico/química , Doxorrubicina/administração & dosagem , Neoplasias/tratamento farmacológico , beta-Glucanas/química , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Linhagem Celular Tumoral , Quitosana/química , Ácido Desoxicólico/administração & dosagem , Doxorrubicina/química , Portadores de Fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas/administração & dosagem , Nanopartículas/química , beta-Glucanas/administração & dosagem
14.
Carbohydr Polym ; 109: 49-55, 2014 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-24815400

RESUMO

Three partially purified polysaccharides were extracted from Phellinus linteus mycelia using hot water, 1% (NH4)2C2O4, and 1.25M NaOH/0.05% NaBH4, and the extracts were named PL-W, PL-A, and, PL-N respectively. PL-N mainly comprised xylose and arabinose with a high molecular weight (Mw) and the highest carbohydrate and uronic acid contents. PL-W and PL-A were mainly composed of glucose with high and low Mw fractions in various ratios. All three polysaccharides existed as compact coils in aqueous solutions and exhibited strong scavenging capacity and antioxidant activities in a concentration-dependent manner. The polysaccharides also had high uronic acid and carbohydrate contents and strong antioxidant activities. The Mws, monosaccharide compositions, and chemical structures of the polysaccharides also affected their antioxidant activities. PL-A and PL-N had better antioxidant activities and could thus be developed as potential natural antioxidant agents for applications in food additives and biomedical industries.


Assuntos
Basidiomycota/química , Sequestradores de Radicais Livres/isolamento & purificação , Polissacarídeos Fúngicos/isolamento & purificação , Compostos de Bifenilo/química , Boroidretos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Radicais Livres/química , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/farmacologia , Temperatura Alta , Humanos , Peso Molecular , Picratos/química , Hidróxido de Sódio/química , Solventes/química , Água/química
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