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1.
Food Chem ; 306: 125615, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31622833

RESUMO

Phycocyanin (PC), a plant-based protein with interesting biological activity, is rarely directly applied in the food industry because it has structural and functional limitations. This study combined ultra-high-pressure (UHP) treatment with glycation to improve PC functionality and explored resulting structural changes using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, scanning electron microscopy, Fourier-transform infrared spectroscopy, circular dichroism, and UV-visible spectroscopy. The UHP treatment obviously improved the speed and degree of glycation and the composite-modified PC (CM-PC) showed high solubility and good emulsifying and foaming performance. Scanning electron microscopy images showed the CM-PC surface was loose and fluffy. Gel electrophoresis, Fourier-transform infrared spectroscopy, and circular dichroism results demonstrated that the content of α-helix decreased from 78.1% in PC to 26.6% in CM-PC, and hydroxyl groups were introduced. UV-visible spectroscopy showed that the mechanism of composite modification involved stretching of the PC and promotion of binding with sugars.


Assuntos
Ficocianina/química , Spirulina/química , Dicroísmo Circular , Eletroforese em Gel de Poliacrilamida , Emulsões/metabolismo , Glicosilação , Pressão , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier
2.
J Food Sci ; 83(10): 2586-2592, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30229911

RESUMO

This study evaluated transepithelial transport mechanisms of Ile-Gln-Pro (IQP) and Val-Glu-Pro (VEP), two ACE-inhibitory peptides derived from Spirulina platensis, using human intestinal Caco-2 cell monolayers. IQP and VEP were absorbed intact through Caco-2 cell monolayers with Papp values of 7.48 ± 0.58 × 10-6 and 5.05 ± 0.74 × 10-6 cm/s, respectively. The transport of IQP and VEP were affected neither by Gly-Pro nor by wortmannin, indicating that they were not PepT1-mediated and did not involve endocytosis. However, transport of IQP and VEP were increased significantly by sodium deoxycholate, suggesting that the major transport mechanism was paracellular. In addition, the increased transport of VEP and IQP were followed with the addition of sodium azide, suggesting influence of energy to the process. The transport of VEP was also increased by verapamil, indicating an apical-to-basolateral flux mediated by P-gp. PRACTICAL APPLICATION: Bioactive peptides derived from food proteins have been considered as potentially ideal products to reduce hypertension because of their safety and positive impacts on health. IQP and VEP are the 2 ACE inhibitory peptides derived from Spirulina platensis, a kind of edible cyanobacteria with rich nutrition and multiple physiological functions, and were demonstrated to inhibit ACE and lower blood pressure in spontaneously hypertensive rats. However, it is prerequisite that such bioactive peptides must be absorbed intact across the intestinal epithelium, so as to exert antihypertensive effects in vivo. This study evaluated transepithelial transport mechanisms of IQP and VEP. It contributes to the study of Spirulina in lowering blood pressure and supports the development of bioactive peptide products.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/metabolismo , Peptídeos/metabolismo , Spirulina/metabolismo , Anti-Hipertensivos/metabolismo , Transporte Biológico , Células CACO-2 , Dipeptídeos/metabolismo , Humanos , Hipertensão/fisiopatologia , Mucosa Intestinal/metabolismo
3.
Food Chem ; 264: 64-72, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29853406

RESUMO

Spirulina platensis is a high-nutrient blue-green alga with a long history as a food supplement. In this study, the mixed fermentation of Spirulina with Lactobacillus plantarum and Bacillus subtilis was investigated using random-centroid optimization to improve deodorization of off-flavor and hydrolysis of protein. Fermented Spirulina with the maximum total viable counts of both organisms achieved best sensory characteristics and degree of proteolysis among those with different maximum biomass. The mixed fermentation noticeably reduced the volatile compounds of Spirulina, and yielded the highest relative contents (>85%) of acetoin and other odorants collectively producing a creamy aroma. Approximately one-third of the Spirulina proteins were hydrolyzed, yielding over 16% polypeptides and increasing the ratio of essential amino acids to total free amino acids to 1.5-fold compared with unfermented Spirulina. Fermentation with B. subtilis and L. plantarum effectively improved the odor and protein availability of Spirulina.


Assuntos
Bacillus subtilis/fisiologia , Lactobacillus plantarum/fisiologia , Spirulina/fisiologia , Acetoína/análise , Acetoína/metabolismo , Aminoácidos/metabolismo , Suplementos Nutricionais , Fermentação , Humanos , Hidrólise , Microbiologia Industrial/métodos , Odorantes/análise , Spirulina/química , Paladar , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo
4.
Mol Med Rep ; 18(2): 1858-1866, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29845248

RESUMO

The aim of the present study was to evaluate the protective effect and mechanism of Letinous edodes foot peptides on ethanol­induced L02 cells. A cell model of ethanol­induced damage was established in vitro to study the effects of the Letinous edodes foot peptides on human L02 hepatocytes. The expression and activity of superoxide dismutase (SOD), malondialdehyde (MDA), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH), following treatment were examined to determine the anti­alcoholism and hepatoprotective functions of Letinous edodes foot peptides. Taking Letinous edodes foot peptides prior to ethanol exposure was more beneficial, which significantly increased SOD activity and the mRNA expression of ADH and ALDH suppressed by ethanol. In addition, the intracellular MDA content, and AST and ALT activity decreased in ethanol­induced L02 cells pretreated with the peptides, when compared with the control. Furthermore, Letinous edodes foot peptides inhibited the ethanol­induced activation of the proinflammatory cytokines, interleukin­6 and tumor necrosis factor­α, and promoted the metabolic regulation factors, AMP­activated protein kinase­α2 and peroxisome proliferator­activated receptor­α.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Fígado/efeitos dos fármacos , Peptídeos/farmacologia , Cogumelos Shiitake/química , Alanina Transaminase/metabolismo , Aspartato Aminotransferases/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Medicamentos de Ervas Chinesas/farmacologia , Etanol/toxicidade , Glutationa Peroxidase/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Fígado/lesões , Fígado/patologia , Malondialdeído/metabolismo , Substâncias Protetoras/química , Substâncias Protetoras/farmacologia , Superóxido Dismutase/metabolismo
5.
J Biosci Bioeng ; 125(6): 682-687, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29395958

RESUMO

Diospyros lotus, a member of the Ebenaceae family, has long been used as a traditional sedative in China. In this study, the antioxidant and hypoglycemic effects of non-fermented and microorganism-fermented D. lotus were explored. The total phenolic and vitamin C contents of microorganism-fermented D. lotus for 24-72 h were less than those of non-fermented. High-performance liquid chromatography showed that the tannic, catechinic, and ellagic acid contents increased significantly upon fermentation for 24 h. D. lotus fermented with Microbacterium flavum for 24 h exhibited the highest DPPH radical scavenging activity (IC50 = 4.18 µg mL-1), and the highest ABTS radical scavenging activity was exhibited at 72 h of fermentation (IC50 = 29.18 µg mL-1). The anti-α-glucosidase activity of fermented D. lotus was higher (2.06-4.73-fold) than that of non-fermented one. Thus, fermented D. lotus is a useful source of natural antioxidants, and a valuable food, exhibiting antioxidant and hypoglycemic properties.


Assuntos
Actinomycetales/metabolismo , Antioxidantes/farmacologia , Diospyros , Hipoglicemiantes/farmacologia , Lactobacillus plantarum/metabolismo , Extratos Vegetais/farmacologia , Diospyros/química , Diospyros/metabolismo , Endófitos/metabolismo , Fermentação , Frutas/química , Frutas/metabolismo , Fenóis/metabolismo , Extratos Vegetais/química , Extratos Vegetais/metabolismo
6.
Molecules ; 22(8)2017 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-28769023

RESUMO

Anredera cordifolia, a climber and member of the Basellaceae family, has long been a traditional medicine used for the treatment of hyperglycemia in China. Two water-soluble polysaccharides, ACP1-1 and ACP2-1, were isolated from A. cordifolia seeds by hot water extraction. The two fractions, ACP1-1 and ACP2-1 with molecular weights of 46.78 kDa ± 0.03 and 586.8 kDa ± 0.05, respectively, were purified by chromatography. ACP1-1 contained mannose, glucose, galactose in a molar ratio of 1.08:4.65:1.75, whereas ACP2-1 contained arabinose, ribose, galactose, glucose, mannose in a molar ratio of 0.9:0.4:0.5:1.2:0.9. Based on methylation analysis, ultraviolet and Fourier transform-infrared spectroscopy, and periodate oxidation the main backbone chain of ACP1-1 contained (1→3,6)-galacturonopyranosyl residues interspersed with (1→4)-residues and (1→3)-mannopyranosyl residues. The main backbone chain of ACP2-1 contained (1→3)-galacturonopyranosyl residues interspersed with (1→4)-glucopyranosyl residues.


Assuntos
Polissacarídeos/isolamento & purificação , Traqueófitas/química , Cromatografia Gasosa , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Estrutura Molecular , Peso Molecular , Extratos Vegetais , Solubilidade , Água
7.
Food Chem ; 231: 25-32, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28450004

RESUMO

This study was to find an effective process to extract bioactive peptides from mushroom foot and determine their effects on activation of alcohol metabolic enzymes in vitro. The optimum extraction assisted by ultra-high-pressure processing of mushroom foot peptides was obtained with a pressure of 400MPa and a processing time of 10min. After ultrafiltration, peptides with molecular weight of 0-3kDa had the highest activity to activate alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) by 70.79% and 71.35%, respectively. Following dextran gel chromatography, two peaks (p-I and p-II) appeared and the activation activities on ADH and ALDH of p-I were 72.00% and 73.43%, both higher than p-II. Nine peptides were found in p-I as determined by LC-MS/MS, and two of them (IPLH and IPIVLL) were synthesized. IPLH activated ADH and ALDH by 42.7% and 29.2% respectively, which were higher than IPIVLL.


Assuntos
Agaricales , Peptídeos , Proteólise , Álcool Desidrogenase , Isoenzimas , Espectrometria de Massas em Tandem
8.
J Sci Food Agric ; 96(5): 1783-9, 2016 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-26037130

RESUMO

BACKGROUND: Spirulina platensis is rich in ß-carotene, which possesses many important biological activities. This study investigated the ultrasound-assisted extraction and purification of ß-carotene from Spirulina platensis by using response surface methodology (RSM), determined its antioxidant capacity in vitro and explored its hypoglycaemic effect in diabetic mice. RESULTS: The raw ß-carotene extract with a concentration of 1942.14 ± 10.03 µg mL(-1) was obtained at the optimised condition by RSM (0.40 of the solid-liquid ratio, 51% of the extraction power, and 17 min of the extraction time), and the purity of evaporated ß-carotene extract reached 816.32 ± 10.57 mg g(-1) after purified by a NKA-9 resin with a sampling and elution rate of 1 mL min(-1) . The ß-carotene extract scavenged 1,1-diphenyl-2-picrylhydrazyl and hydroxyl free radicals with the highest ratios of 44 ± 0.26% and 35 ± 0.45% respectively, and exhibited strong inhibiting capacity on anti-lipid peroxidation. The blood glucose level of streptozotocin-induced diabetic mice was significantly reduced from 15.81 ± 1.71 mmol L(-1) to 8.10 ± 0.88 mmol L(-1) after 10 d administration of the ß-carotene extract [100 mg kg(-1) body weight (BW)], and the increased food and water intakes in the diabetic mice were also significantly relieved after ß-carotene treatment. CONCLUSION: Our results suggested that extraction of ß-carotene from Spirulina platensis had potential prospects in scaled-up industrialisation and healthcare applications.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Spirulina/química , beta Caroteno/uso terapêutico , Animais , Compostos de Bifenilo , Glicemia , Hipoglicemiantes/química , Peroxidação de Lipídeos/efeitos dos fármacos , Picratos , beta Caroteno/química
9.
J Agric Food Chem ; 59(2): 559-63, 2011 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-21182294

RESUMO

The antihypertensive effect of an angiotensin I-converting enzyme (ACE) inhibitory peptide Ile-Gln-Pro (IQP), whose sequence was derived from Spirulina platensis , was investigated in spontaneously hypertensive rats (SHRs) for 1 week. The weighted systolic blood pressure (SBP) and diastolic blood pressure (DBP) of the peptide IQP-treated group were significantly lower than those of the negative control group from the third and fourth days, respectively. Accompanying the blood pressure reduction, a significant regulation of the expression of major components of the renin-angiotensin system (RAS) was found in the treatment group, including downregulation of the mRNA levels of renin, ACE, and the angiotensin II type 1 (AT1) receptor in the kidney, as well as serum angiotensinogen (Ang), ACE, and angiotensin II (Ang II) concentrations. The treatment group also showed upregulation of mRNA expression of the angiotensin II type 2 (AT2) receptor in the kidney. Our findings suggested that IQP might be of potential use in the treatment of hypertension.


Assuntos
Anti-Hipertensivos/administração & dosagem , Hipertensão/tratamento farmacológico , Peptídeos/administração & dosagem , Animais , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Expressão Gênica/efeitos dos fármacos , Humanos , Hipertensão/genética , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Masculino , Ratos , Ratos Endogâmicos SHR , Renina/genética , Renina/metabolismo
10.
J Agric Food Chem ; 58(12): 7166-71, 2010 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-20509691

RESUMO

An angiotensin I-converting enzyme (ACE) inhibitory peptide Ile-Gln-Pro with an IC(50) value of 5.77 +/- 0.09 microM was purified from the alcalase digests of Spirulina platensis by gel filtration chromatography and two steps of reverse-phase high-performance liquid chromatography (RP-HPLC). The peptide was synthesized and showed resistance to in vitro digestion by gastrointestinal proteases. Kinetics studies indicated that the peptide was a noncompetitive inhibitor and that the K(i) value was 7.61 +/- 0.16 microM. Oral administration of Ile-Gln-Pro at a dosage of 10 mg/kg showed significant decreases of the weighted systolic blood pressure (SBP) and diastolic blood pressure (DBP) in spontaneously hypertensive rats (SHR) at 4, 6, and 8 h after treatment. The results showed that the ACE inhibitory peptide from Spirulina platensis may have potential for use in the prevention and treatment of hypertension.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Anti-Hipertensivos/isolamento & purificação , Peptídeos/isolamento & purificação , Spirulina/química , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/síntese química , Inibidores da Enzima Conversora de Angiotensina/química , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/síntese química , Anti-Hipertensivos/química , Bacillus/enzimologia , Proteínas de Bactérias/química , Modelos Animais de Doenças , Humanos , Hidrólise , Hipertensão/tratamento farmacológico , Cinética , Masculino , Peptídeos/administração & dosagem , Peptídeos/síntese química , Peptídeos/química , Ratos , Ratos Endogâmicos SHR , Subtilisinas/química
11.
Br J Nutr ; 103(11): 1573-6, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20102673

RESUMO

Increasing attention has been paid to Spirulina for its potential clinical uses. The present study investigated the protection by dietary Spirulina platensis against d-galactosamine (d-GalN)- and acetaminophen (APAP)-induced hepatitis in ICR mice. Mice in each group (n 6) were fed with a standard diet (American Institute of Nutrition (AIN)-93G), a positive control diet containing 0.5 % butylated hydroxytoluene (BHT), or a diet containing 3, 6 or 9 % S. platensis for 1 week. On the last day the mice were treated with d-GalN (300 mg/kg body weight, intraperitoneally) or APAP (150 mg/kg body weight, intraperitoneally) and 24 h later the mice were killed. The doses of both 6 and 9 % S. platensis were found to significantly alleviate the increase of serum glutamate oxaloacetoacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) activities in d-GalN- or APAP-intoxicated mice. The observation was very similar to that of the positive control groups. Two more experiments were carried out to investigate the involvement of thiobarbituric acid-reactive substances (TBARS) and IL-18 in the suppression of 6 % S. platensis on d-GalN- and APAP-induced hepatitis. The significant increase of GOT and GPT activities was found to be accompanied with the elevation of hepatic TBARS level, IL-18 mRNA expression and serum IL-18 concentration, and was significantly alleviated by supplementation with 6 % S. platensis in diets. These results showed that dietary S. platensis could provide a significant protection against d-GalN- and APAP-induced liver injuries, and IL-18 and lipid peroxidation might be involved in the protective influence of S. platensis.


Assuntos
Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Dieta , Galactosamina/toxicidade , Spirulina , Acetaminofen/administração & dosagem , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Doença Hepática Induzida por Substâncias e Drogas/sangue , Galactosamina/administração & dosagem , Interleucina-18/sangue , Interleucina-18/genética , Fígado/química , Masculino , Malondialdeído/análise , Camundongos , Camundongos Endogâmicos ICR , RNA Mensageiro/análise , Substâncias Reativas com Ácido Tiobarbitúrico/análise
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