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1.
Pediatr Res ; 95(1): 227-232, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37580551

RESUMO

BACKGROUND: children who undergo CPB operations are at an elevated risk of infection due to immunosuppression. This study aims to investigate the association between lymphopenia following CPB and early postoperative infection in children. METHODS: A retrospective analysis including 41 children under 2 years old underwent CPB. Among them, 9 subjects had an early postoperative infection, and 32 subjects were period-matched without infection. Inflammatory cytokines, serum CRP and PCT values were measured in plasma, additionally, circulating total leucocyte and lymphocyte subpopulations were counted. RESULTS: Infected subjects exhibited significantly higher levels of inflammatory cytokines, including IL-6, IL-8, IL-10, IL-1ß and TNF-α, than non-infected subjects after CPB. Additionally, lower absolute number of lymphocyte and their subpopulations CD3+ T cells, CD4+ T-helper cells and CD8+cytotoxic T-cells, were observed in infected subjects. The impairment of T-cells Immune was found to be associated with higher levels of inflammatory cytokines IL-10. The ROC demonstrated that the absolute number of CD3+ T-cells <1934/ul, CD4+ T helper cells <1203/ul and CD8+cytotoxic T-cells <327/ul were associated with early postoperative infection. CONCLUSION: Higher levels of inflammatory cytokines resulted in T-cells lymphopenia after CPB, which significantly increasing the risk of postoperative infection in infants and young children. IMPACT: Infection complications after cardiopulmonary bypass (CPB) in pediatric CHD patients are serious issues, identifing the infection from after CPB remains a challenging. CPB can release numerous inflammatory cytokines associated with T cells lymphopenia, which increases the risk of postoperative infection after surgery. Monitoring T cells lymphopenia maybe more beneficial to predict early postoperative infection than C-reactive protein and procalcitonin.


Assuntos
Ponte Cardiopulmonar , Linfopenia , Lactente , Humanos , Criança , Pré-Escolar , Ponte Cardiopulmonar/efeitos adversos , Interleucina-10 , Estudos Retrospectivos , Citocinas , Linfócitos T , Linfopenia/etiologia
2.
Front Nutr ; 10: 1241580, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37693241

RESUMO

In this paper, we study the effect of microbial fermentation on the nutrient composition and flavor of sweet potato slurry, different strains of Aspergillus niger, Saccharomyces cerevisiae, Lactobacillus plantarum, Bacillus coagulans, Bacillus subtilis, Lactobacillus acidophilus, and Bifidobacterium brevis were employed to ferment sweet potato slurry. After 48 h of fermentation with different strains (10% inoculation amount), we compared the effects of several strains on the nutritional and functional constituents (protein, soluble dietary fiber, organic acid, soluble sugar, total polyphenol, free amino acid, and sensory characteristics). The results demonstrated that the total sugar level of sweet potato slurry fell significantly after fermentation by various strains, indicating that these strains can utilize the nutritious components of sweet potato slurry for fermentation. The slurry's total protein and phenol concentrations increased significantly, and many strains demonstrated excellent fermentation performance. The pH of the slurry dropped from 6.78 to 3.28 to 5.95 after fermentation. The fermentation broth contained 17 free amino acids, and the change in free amino acid content is closely correlated with the flavor of the sweet potato fermentation slurry. The gas chromatography-mass spectrometry results reveal that microbial fermentation can effectively increase the kinds and concentration of flavor components in sweet potato slurry, enhancing its flavor and flavor profile. The results demonstrated that Aspergillus niger fermentation of sweet potato slurry might greatly enhance protein and total phenolic content, which is crucial in enhancing nutrition. However, Bacillus coagulans fermentation can enhance the concentration of free amino acids in sweet potato slurry by 64.83%, with a significant rise in fresh and sweet amino acids. After fermentation by Bacillus coagulans, the concentration of lactic acid and volatile flavor substances also achieved its highest level, which can considerably enhance its flavor. The above results showed that Aspergillus niger and Bacillus coagulans could be the ideal strains for sweet potato slurry fermentation.

3.
Front Nutr ; 10: 1116982, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36908923

RESUMO

Bacillus subtilis has been extensively studied for its ability to inhibit the growth of harmful microorganisms and its high protease activity. In this study, Bacillus subtilis was used to ferment gluten and assess the effects of the fermentation process on the physicochemical, microstructure and antioxidant properties of gluten. The results of Fourier infrared spectroscopy (FT-IR) and circular chromatography (CD) showed a significant decrease in the content of α-helix structures and a significant increase in the content of ß-sheet structures in gluten after fermentation (p < 0.05). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that glutenin was degraded into small molecular peptides with a molecular weight of less than 26 kDa after 24 h of fermentation; meanwhile, the fermentation process significantly increased the free amino acid content of the samples (p < 0.05), reaching 1923.38 µg/mL at 120 h of fermentation, which was 39.46 times higher than that at 24 h of fermentation (p < 0.05). In addition, the fermented back gluten has higher free radical scavenging activity and iron reduction capacity. Therefore, fermented gluten may be used as a functional food to alleviate oxidative stress. This study provides a reference for the high-value application of gluten.

4.
Appl Biochem Biotechnol ; 195(7): 4399-4413, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36696038

RESUMO

Fructose, which is produced by the isomerization of glucose isomerase, is a crucial precursor for the biosynthesis of rare sugars. In this study, thermophilic glucose isomerases (GI) from Caldicellulosiruptor acetigenus (CAGI), Thermoanaerobacter thermocopriae (TTGI), and Thermotoga petrophila (TPGI) were screened from GenBank database by a virtual probe and were successfully expressed in Escherichia coli BL21(DE3). The results of characterization demonstrated that the optimal pH for CAGI and TTGI were 8.0 and were maintained at 80% in a slightly acidic environment. The relative residual activities of CAGI and TTGI were found to be 40.6% and 52.6%, respectively, following an incubation period of 24 h at 90 ℃. Furthermore, CAGI and TTGI exhibited superior catalytic performance that their reaction equilibrium both reached only after an hour at 85 ℃ with 200 g/L glucose, and the highest conversion rates were 54.2% and 54.1%, respectively. This study identifies competitive enzyme candidates for fructose production in the industry with appreciable cost reduction.


Assuntos
Aldose-Cetose Isomerases , Glucose , Glucose/química , Frutose/química , Aldose-Cetose Isomerases/genética , Aldose-Cetose Isomerases/química , Clostridiales , Clostridium , Tecnologia , Concentração de Íons de Hidrogênio , Proteínas Recombinantes
5.
Food Funct ; 13(19): 9856-9867, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36047913

RESUMO

Neuroinflammation and intestinal microbiota cause pathological progression of Alzheimer's disease (AD), leading to neurodegeneration and cognitive decline. This study investigates the effects of wheat embryo globulin nutrient (WEGN) on depression, neuroinflammation, and intestinal microbial disorder caused by AD and its protective mechanism on cognitive impairment. Results demonstrated that rats in the WEGN group have lower feed intake but higher body weight than those in the control group. Notably, rats in the WEGN group have a higher number of cross grids and uprights and a smaller amount of fecal particles than those in the control group. Biochemical examinations revealed that rats in the WEGN group had lower expression of interleukin-1ß, interleukin-6, and tumor necrosis factor α in hippocampus tissue and the expression of genes and proteins related to the TLR4/MyD88/NF-κB signaling pathway in AD rats was down-regulated compared to those in the control group. The 16S rRNA gene sequencing results demonstrated that WEGN treatment inhibits the increase of Erysipelotrichaceae, Erysipelatoclostridium, Erysipelotrichaceae, Corynebacterium, and Frisingicoccus, and the reduction of Lactobacillus in AD rats. WEGN has potential value as a practical food in alleviating neuroinflammation-related diseases such as AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Globulinas , Animais , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Nutrientes , RNA Ribossômico 16S , Ratos , Ratos Sprague-Dawley , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Triticum/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
6.
Front Nutr ; 9: 803440, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35600826

RESUMO

Insoluble dietary fiber (IDF) were isolated from wheat bran (WB) after microbial fermentation with single or mixed strain [Lactobacillus plantarum, Lactobacillus acidophilus, Bacillus subtilis or mixed lactic acid bacteria (L. plantarum and L. acidophilus with ration of 1:1)]. Structure, physicochemical, functional properties, and antioxidant activity of the wheat bran insoluble dietary fiber (W-IDF) modified by fermentation were studied. Fourier transformed infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM) analysis suggested the successful modification of W-IDF. After fermentation with L. plantarum and mixed lactic acid bacteria, the water retention capacity (WRC), oil retention capacity (ORC), and water swelling capacity (WSC) of W-IDF were improved. The sodium cholate adsorption capacity (SCAC), and cation exchange capacity (CEC) of W-IDF modified with L. acidophilus fermentation were significantly increased. Although the cholesterol adsorption capacity (CAC) of W-IDF decreased after modification with probiotic fermentation, nitrite ion adsorption capacity (NIAC), and total phenolic content (TPC) were enhanced. Additionally, W-IDF modified by fermentation with B. subtilis or mixed lactic acid bacteria exhibited superior antioxidant capacity verified by DPPH, ABTS and total reducing power assays. Results manifested that microbial fermentation is a promising methods to modify the W-IDF to provide high-quality functional IDF for food processing and human health management.

7.
J Food Sci ; 87(6): 2549-2562, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35607810

RESUMO

Wheat embryo albumin (WEA) extracted from wheat embryo possesses multiple effects including antioxidant, anti-inflammatory, and immunoregulatory effects. In this study, a single factor experiment was conducted to determine the optimal enzymolysis conditions of WEA. Five components (F1-F5) were obtained via ultrafiltration, among which F3 (molecular weight 3-5 kDa) displayed the best antioxidant activity. WEA and F3 were characterized by transmission electron microscopy, scanning electron microscopy, circular dichroism spectrum analysis, and amino acid composition tests. Results revealed that F3 significantly increased the contents of ß-tablets, aromatic amino acids, and hydrophobic amino acids compared to WEA. LC-MS/MS analysis demonstrated that F3 had more tyrosine and histidine moieties than WEA. Moreover, analysis of the Maillard reaction products (MRPs) showed that F3-MRPs had strong browning strength, ultraviolet absorption, higher number of free amino acids, and umami amino acid ratio compared with WEA. In conclusion, enzymolysis can improve the functional properties of WEA, which broadens the application spectrum of WEA in food and pharmaceutical fields. PRACTICAL APPLICATION: This study provides a new approach for identifying potential antioxidants and developing functional foods from WEA, and broadens the application spectrum of wheat germ resources.


Assuntos
Antioxidantes , Produtos Finais de Glicação Avançada , Albuminas , Aminoácidos/química , Antioxidantes/química , Cromatografia Líquida , Produtos Finais de Glicação Avançada/química , Reação de Maillard , Peptídeos , Espectrometria de Massas em Tandem , Triticum
8.
Food Funct ; 13(5): 2559-2569, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35166271

RESUMO

Wheat germ protein including wheat embryo albumin (WEA) demonstrates extensive biological activity. In vitro dynamic digestion of WEA was carried out under simulated gastrointestinal conditions. Anti-fatigue effects of WEA were evaluated using mice forced to swim. Results indicated that the digestibility of WEA decreased, antioxidant activity and the contents of aromatic amino acids (AAA) and hydrophobic amino acids (HAA) were significantly increased, and the ratio of essential amino acid (EAA) and non-essential amino acid (NEAA) were also changed during digestion. WEA significantly prolonged swimming time, reduced the accumulation of lactate dehydrogenase (LDH), blood urea nitrogen (BUN), and creatine kinase (CK). WEA also increased glycogen storage in liver and muscle. Meanwhile, WEA revealed antioxidant activity through enhancing the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) while decreasing the level of malondialdehyde (MDA). Notably, WEA enhanced the mRNA expression of mitochondrial biogenesis factors in the skeletal muscles of the mice. Therefore, WEA is suitable for preparation of energy foods with attractive anti-fatigue and health benefits.


Assuntos
Albuminas/farmacologia , Antioxidantes/farmacologia , Músculo Esquelético/efeitos dos fármacos , Triticum , Albuminas/química , Animais , Antioxidantes/química , Compostos de Bifenilo , Digestão/efeitos dos fármacos , Masculino , Camundongos , Picratos , Distribuição Aleatória , Natação
9.
Brain Res ; 1773: 147672, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34606748

RESUMO

Wheat embryo globulin nutrient (WEGN), with wheat embryo globulin (WEG) as the main functional component, is a nutritional combination that specifically targets memory impairment. In this study, we explored the protective role of WEGN on Alzheimer's disease (AD)-triggered cognitive impairment, neuronal injury, oxidative stress, and acetylcholine system disorder. Specifically, we established an AD model via administration of d-galactose (d-gal) and Aluminum chloride (AlCl3) for 70 days, then on the 36th day, administered animals in the donepezil and WEGN (300, 600, and 900 mg/kg) groups with drugs by gavage for 35 days. Learning and memory ability of the treated rats was tested using the Morris water maze (MWM) and novel object recognition (NOR) test, while pathological changes and neuronal death in their hippocampus CA1 were detected via HE staining and Nissl staining. Moreover, we determined antioxidant enzymes by measuring levels of superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) in serum, cortex, and hippocampus, whereas changes in the acetylcholine system were determined by evaluating choline acetyltransferase (ChAT), and acetylcholinesterase (AChE) activities, as well as choline acetylcholine (Ach) content. Results revealed that rats in the WEGN group exhibited significantly lower escape latency, as well as a significantly higher number of targeted crossings and longer residence times in the target quadrant, relative to those in the model group. Notably, rats in the WEGN group spent more time exploring new objects and exhibited lower damage to their hippocampus neuron, had improved learning and memory activity, as well as reversed histological alterations, relative to those in the model group. Meanwhile, biochemical examinations revealed that rats in the WEGN group had significantly lower MDA levels and AChE activities, but significantly higher GSH, SOD, and ChAT activities, as well as Ach content, relative to those in the model group. Overall, these findings indicate that WEGN exerts protective effects on cognitive impairment, neuronal damage, oxidative stress, and choline function in AD rats treated by d-gal/AlCl3.


Assuntos
Disfunção Cognitiva/tratamento farmacológico , Hipocampo/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Triticum , Cloreto de Alumínio , Animais , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/metabolismo , Modelos Animais de Doenças , Donepezila/farmacologia , Donepezila/uso terapêutico , Galactose , Glutationa Peroxidase/metabolismo , Hipocampo/metabolismo , Masculino , Malondialdeído/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
10.
Food Chem Toxicol ; 151: 112101, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33684518

RESUMO

Diosgenin (DG) isolated from yam roots revealed various bioactivities and applications as drug carrier. In the present study, a conjugate of DG with cytarabine (Ara-C) was used to prepare the self-assembled nanoparticles (NPs) of DG-Ara-C by a nanoprecipitation method. Dynamic light scattering (DLS) as well as transmission electron microscopy (TEM) were employed to analyze the size and the morphology of NPs, respectively. The stability and absorption of DG-Ara-C NPs were measured. Additionally, the cytotoxicity of the NPs was determined via MTT assay. The results indicated that the average particle size of DG-Ara-C NPs was around 190 nm with a narrow size distribution (PDI = 0.1). TEM showed that DG-Ara-C NPs had a spherical morphology. Compared to free DG or Ara-C, the self-assembled DG-Ara-C NPs exhibited a better anti-tumor activity against solid tumor cells as well as leukemia cells. In conclusion, DG possesses dual role in the self-assembled NPs of DG-Ara-C conjugate, being as a promising anticancer drug and drug carrier.


Assuntos
Antimetabólitos Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos , Citarabina/química , Diosgenina/química , Nanopartículas/química , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Citarabina/administração & dosagem , Citarabina/farmacologia , Diosgenina/administração & dosagem , Diosgenina/farmacologia , Portadores de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos
11.
Food Chem Toxicol ; 148: 111920, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33346046

RESUMO

Diosgenin (DG), a steroidal saponin, is mainly found in yam tubers. DG and its derivatives displayed significant pharmacological activities against inflammatory, hyperlipidemia, and various cancers. DG was selected to modify the cancer chemotherapeutic agent cytarabine (Ara-C) due to its anti-tumor activities as well as lipophilicity. After characterization, the biomembrane affinity and the kinetic thermal processes of the obtained DG-Ara-C conjugate were evaluated by differential scanning calorimetry (DSC). Thin hydration method with sonication was applied to prepare the DG-Ara-C liposomes without cholesterol since the DG moiety has the similar basic structure with cholesterol with more advantages. Dynamic Light Scattering (DLS) analysis and cytotoxic analysis were employed to characterize the DG-Ara-C liposomes and investigate their biological activities, respectively. The results indicated that DG changed the biomembrane affinity of Ara-C and successfully replaced the cholesterol during the liposome preparation. The DG-Ara-C liposomes have an average particle size of around 116 nm with a narrow size distribution and revealed better anti-cancer activity against leukemia cells and solid tumor cells than that of free DG or Ara-C. Therefore, it can be concluded that DG displayed the potential application as an anti-cancer drug carrier to improve the bio-activities, since DG counted for a critical component in modulating the biomembrane affinity, preparation of liposome, and release of hydrophilic Ara-C from lipid vesicles.


Assuntos
Antineoplásicos/farmacologia , Citarabina/análogos & derivados , Citarabina/farmacologia , Diosgenina/análogos & derivados , Diosgenina/farmacologia , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citarabina/síntese química , Diosgenina/síntese química , Portadores de Fármacos/síntese química , Portadores de Fármacos/farmacologia , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lipossomos/síntese química , Lipossomos/farmacologia
12.
Ying Yong Sheng Tai Xue Bao ; 31(6): 1909-1915, 2020 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34494743

RESUMO

The numerical classification and ordination of plant communities can reveal the relationship between plant distribution and environment, with implications on vegetation restoration and forest management. Community types were classified using a clustering method based on 45 forest dynamic plots with each area of 0.04 hm2 in Wuchaoshan, Hangzhou, Zhejiang Province, China. The ordination of plant community and the relationship between communities and edaphic variables (soil nutrient availability and topography) were explored using redundancy analysis. Results showed there were three community types in the study area, including Schima superba community type, Quercus fabri-Symplocos anomala community type, and Cyclobalanopsis glauca community type. Stem density and basal area of trees were not significantly different among those community types. Species richness in the C. glauca community was higher than that in S. superba community, but not significantly different from the Q. fabri-S. anomala community. Results from the redundancy analysis showed that community distribution was significantly related to edaphic factors. Topographic and soil factors accounted for 46.4% of the total variation in community distribution while total soil phosphorus, available phosphorus, available potassium, elevation, slope, aspect, and canopy openness had significant effects on community composition. Total soil phosphorus, available potassium, and altitude were the main factors influencing community distribution in Wuchaoshan. 53.6% of the total variation in community distribution were not explained, perhaps due to anthropogenic disturbance.


Assuntos
Florestas , Theaceae , China , Solo , Árvores
13.
Int J Biol Macromol ; 146: 887-896, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31669658

RESUMO

In this study, four sequentially extracted polysaccharides (AEPs) from Amana edulis were modified by sulphation, phosphorylation, and carboxylation modifications (S-AEPs, P-AEPs, C-AEPs), and compared for their anti-oxidant activities. After modification, sugar and protein contents were decreased and uronic acid content was increased in comparison to native AEPs. UV absorption showed similar maximum absorption peaks of modified derivatives which indicated their homogeneous nature. FTIR spectra confirmed the conversion of hydroxyl groups to OS, COO, and POH bonds, respectively. The phosphorylated derivatives (P-AEPs) displayed the highest DPPH, hydroxyl radical, and ferrous ions radical scavenging abilities. Sulfated polysaccharides (S-AEPs) were observed with high reducing ability. The C-AEPs maintained the stable antioxidant properties after carboxylation modification. Our results indicated that the chemical modification of different polysaccharide components has significantly affected their antioxidant potential for their use in food industry and human health.


Assuntos
Antioxidantes/farmacologia , Liliaceae/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Sulfatos/química , Benzotiazóis/química , Compostos de Bifenilo/química , Sequestradores de Radicais Livres/farmacologia , Quelantes de Ferro/farmacologia , Oxirredução , Fosforilação , Picratos/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Ácidos Sulfônicos/química
14.
Food Chem ; 306: 125560, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31590002

RESUMO

To control the oxidation in chicken fat by immobilized lipoxygenase (LOX), Maillard reaction products (MRPs) with chicken flavor were prepared and analyzed for flavor mechanism. >50% activity of immobilized LOX was retained after repeated use for five times or five weeks. The oxidized chicken fats were prepared by thermal, free LOX, and immobilized LOX treatments. After addition of chicken fats, Maillard reaction produced more aliphatic aldehydes and alcohols (126.0-839.5 ng/g and 493.5-2332.4 ng/g, respectively) which resulted in noticeable enhanced reaction, but the content of sulfur compounds such as thiols and thiophenes decreased significantly (870.8-1233.9 ng/g and 1125.0-2880.3 ng/g, respectively), and the structure of sulfur compounds could easily form alkyl side chains. However, there was no significant difference in sensory and flavors between oxidized chicken after treatments, which may be related to oxidized degree. The mechanism was proposed or aromatic effects of oxidized chicken fat on flaxseed derived MRPs.


Assuntos
Galinhas , Gorduras/metabolismo , Aromatizantes/química , Linho/química , Lipoxigenase/metabolismo , Animais , Enzimas Imobilizadas/metabolismo , Gorduras/química , Produtos Finais de Glicação Avançada/análise , Reação de Maillard , Oxirredução , Glycine max/enzimologia , Paladar
15.
Proc Natl Acad Sci U S A ; 116(52): 26674-26681, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31843905

RESUMO

Human activities have shaped large-scale distributions of many species, driving both range contractions and expansions. Species differ naturally in range size, with small-range species concentrated in particular geographic areas and potentially deviating ecologically from widespread species. Hence, species' responses to human activities may be influenced by their geographic range sizes, but if and how this happens are poorly understood. Here, we use a comprehensive distribution database and species distribution modeling to examine if and how human activities have affected the extent to which 9,701 vascular plants fill their climatic potential ranges in China. We find that narrow-ranged species have lower range filling and widespread species have higher range filling in the human-dominated southeastern part of China, compared with their counterparts distributed in the less human-influenced northwestern part. Variations in range filling across species and space are strongly associated with indicators of human activities (human population density, human footprint, and proportion of cropland) even after controlling for alternative drivers. Importantly, narrow-ranged and widespread species show negative and positive range-filling relationships to these human indicators, respectively. Our results illustrate that floras risk biotic homogenization as a consequence of anthropogenic activities, with narrow-ranged species becoming replaced by widespread species. Because narrow-ranged species are more numerous than widespread species in nature, negative impacts of human activities will be prevalent. Our findings highlight the importance of establishing more protected areas and zones of reduced human activities to safeguard the rich flora of China.

16.
Foods ; 8(10)2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31640121

RESUMO

Herein, feasibility of supplementing wheat flour with Chinese yam powder (CYP) for noodle preparation was assessed. After supplementation with CYP, the alterations in chemical, texture, cooking, rheological, and microstructure attributes of noodles were observed. Due to higher protein and lower gluten, 20% of CYP promoted the stable network of gluten and starch particles. However, the excessive addition reduced the flexibility and the chewiness. The adverse changes were observed at 40% substitution level in texture profile analysis (TPA) and rheological parameters due to disrupted gluten-protein network which accelerated the exposure of starch particles. The CYP incorporation up to 20% showed better mouthfeel but further addition lowered the total sensory scores. Scanning Electronic Microscopy (SEM) analysis confirmed the modifications in noodles microstructure as CYP addition affected starch granule structure. In general, 30% substitution significantly improved the textural and rheological properties of noodles, indicating the potential of Chinese yam powder for industrial application.

17.
Int J Biol Macromol ; 137: 160-168, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31255623

RESUMO

The rheological properties and emulsifying behavior of four polysaccharides (HBSS, CHSS, DASS, and CASS) sequentially extracted from Amana edulis (AEPs) were investigated under various concentrations, temperatures, pH levels, and ionic strengths. The apparent viscosity of the four AEPs solutions at 1% (w/w) concentration were found to be CHSS > DASS > HBSS > CASS. When the AEPs were heated to 100 οC, they showed lower colloidal viscosity, whereas after refrigeration and chilling, higher apparent viscosities were observed. The apparent viscosity of four AEPs at pH 10 or pH 4 was lower than that at pH 7. The apparent viscosity increased at a lower sodium ion concentration and then declined with an increase in ion concentration. The storage modulus (G') and loss modulus (G″) increased with an increase in oscillation frequency. The emulsifying activity and stability were enhanced as the concentration of the four AEPs increased. The emulsifying activity and stability of the AEPs were steady within the pH range of 2-10 and NaCl concentration range of 0-0.4 mol/L. Our results implied that these polysaccharides can be utilized as a novel hydrocolloid source for natural thickeners in the food industry.


Assuntos
Liliaceae/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Reologia , Cálcio/química , Emulsões , Indústria Alimentícia , Concentração de Íons de Hidrogênio , Temperatura , Viscosidade
18.
Int J Biol Macromol ; 137: 1-7, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31252008

RESUMO

The effects of concentration, temperature, pH, and salt ion concentration on the apparent viscosity of potato peel (PP) polysaccharide solutions were studied. The results showed that the PP polysaccharides exhibited the characteristics of "non-Newtonian fluid". The apparent viscosity of the PP polysaccharides decreased under acidic, alkaline conditions, and with the increasing temperature. At the increasing concentration of PAC with the addition of four ion concentrations, the apparent viscosity was decreased gradually. The apparent viscosity of PAL increased with four ion concentrations, while that of PW increased initially with the rising concentration of Na+, Mg2+, and K+ and then decreased. Addition of Ca2+ lowered the apparent viscosity initially which was followed by further increase. The results of dynamic rheological experiment showed that the loss modulus G″ of PP polysaccharide was higher than the storage modulus G' at lower frequencies, and vice versa at higher frequencies. With the increasing concentration of PP polysaccharides, the values of the intersection of G' and G″ were lowered. The results showed that the rheological properties of PP polysaccharide solutions were affected by concentration, temperature, pH, and salt ions.


Assuntos
Polissacarídeos/química , Reologia , Solanum tuberosum/química , Armazenamento de Alimentos , Concentração de Íons de Hidrogênio , Polissacarídeos/isolamento & purificação , Resistência ao Cisalhamento , Temperatura , Viscosidade
19.
Food Chem Toxicol ; 131: 110580, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31202938

RESUMO

In present study, the acute, genetic, and sub-chronic toxicities of flaxseed derived Maillard reaction products (MRPs) were investigated. Acute toxicity results showed that the 50% lethal dose (LD50) of MRPs in rats was >15.0 g/kg body weight (BW); whereas, the 50% effective dose (ED50) of MRPs was 12.3 g/kg BW. Ames test demonstrated that the back-mutation colonies for MRPs addition of 5,000 µg/dish was positive, which displayed certain mutagenicity. There were no significant differences in micronucleus rate and sperm deformity rate among different dose groups. The sub-chronic toxicity confirmed that less than 0.75 gMRPs/kg BW intake did not affect weight, food intake, mortality, gross pathology, histology, hematology, and serum biochemistry. The obtained results can provide an imperative reference on the safety of a meat flavoring agents.


Assuntos
Linho/química , Produtos Finais de Glicação Avançada/toxicidade , Sementes/química , Alanina Transaminase/metabolismo , Animais , Medula Óssea/patologia , Feminino , Rim/patologia , Fígado/patologia , Masculino , Camundongos , Testes de Mutagenicidade , Mutagênicos/toxicidade , Ratos Sprague-Dawley , Testes de Toxicidade Aguda , Testes de Toxicidade Subcrônica
20.
Food Chem ; 297: 124983, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253271

RESUMO

To improve the industrial application of wheat bran insoluble dietary fiber (W-IDF), three modification methods (carboxymethylation, complex enzymatic hydrolysis, and ultrafine comminution) were compared on the basis of structural, physicochemical, functional, and antioxidant properties of W-IDF. FT-IR, DSC and SEM analysis showed that modifications contributed to alteration in morphology and arrangement of chemical bonds in W-IDF. Carboxymethylation effectively improved the water retention (WRC), water swelling (WSC), and glucose adsorption capacities (GAC); complex enzymatic hydrolysis greatly improved the oil retention (ORC), GAC, and nitrite ion adsorption capacities (NIAC). Although ultrafine comminution reduced the WRC and ORC, while positively influenced the GAC and NIAC. Moreover, total phenol content, total antioxidant capacity, DPPH radical scavenging capacity, Fe2+ chelating capacity and total reducing power were improved in modified W-IDF. Our results confirmed that carboxymethylation can improve the nutritive quality and sensory properties of W-IDF (nutritive ingredient) in food products.


Assuntos
Antioxidantes/análise , Fibras na Dieta/análise , Complexos Multienzimáticos/metabolismo , Triticum/química , Adsorção , Antioxidantes/metabolismo , Fenômenos Químicos , Fibras na Dieta/metabolismo , Glucose/metabolismo , Hidrólise , Metilação , Valor Nutritivo , Material Particulado , Silicones
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