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1.
J Food Sci Technol ; 53(1): 391-400, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26787958

RESUMEN

In this study, protein-rich waste of tomato processing industries was fermented by Bacillus subtilis A14h to produce hydrolysates with antioxidant and antibacterial activities. The effects of different levels of initial pH, incubation temperature, fermentation time, protein concentration and inoculum size on proteolytic activity, release of amino acids and peptides, antioxidant and antibacterial activities of hydrolysates were evaluated and optimized by using response surface methodology (RSM). Results showed that all the evaluated variables significantly influenced the hydrolysis and bioactivities of hydrolysates in polynomial models. Hydrolysates showed remarkable 2, 2'-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity (up to 70 %), ferric ion reducing power, and inhibitory activity against B. cereus (up to 69.8 %) and E. coli (up to 29.8 %). Overall, good correlation between the concentration of amino acids and peptides, and antioxidant as well as antibacterial activities (in particular for B. cereus inhibition activity) was observed. Finally, optimum conditions for fermentative conversion of tomato waste proteins to antioxidant and antibacterial hydrolysates were established. Results of this study showed that tomato waste protein can be valorized to produce antioxidant and antibacterial hydrolysates in a fermentative system using B. subtilis A14h.

2.
J Food Sci Technol ; 52(4): 2428-33, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25829629

RESUMEN

In this study, the effects of fat (0.5 %, 3.2 % and 5.0 %), inulin (0.0 and 1.0 %) and starter culture (0.0 %, 0.5 %, 1.0 % and 1.5 %) on the angiotensin converting enzyme (ACE)-inhibitory activity of probiotic yogurt containing non-viable bacteria were assessed. Proteolytic activities of bacteria were also investigated. Yogurts were prepared either using a sole yogurt commercial culture including Streptococcus thermophilus and Lactobacillus delbrueckii subs. bulgaricus or bifidobacterium animalis BB-12 and Lactobacillus acidophilus La5 in addition to yogurt culture. Relative degrees of proteolysis were found to be considerably higher in yogurt samples than UHT milk as the control. Both regular and probiotic yogurts showed considerable ACE-inhibitory activities. Results showed that degree of proteolysis was not influenced by different fat contents, while was increased by high concentration of starter culture (1.5 % w/w) and reduced by inulin (1 % w/w). ACE-inhibitory activities of yogurt were also negatively affected by the presence of inulin and high levels of fat (5 % w/w). Moreover, yogurt containing probiotic bacteria showed higher inhibitory against ACE in comparison to the yogurt prepared with non-probiotic strains.

3.
Food Sci Technol Int ; 29(4): 395-405, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35502832

RESUMEN

Emulsion is a colloidal dispersion for delivering natural antimicrobial, antioxidant, and bioactive compounds to improve the product's quality. The present study aimed to develop the active emulsion film based on whey protein isolate (WPI) by adding oleic acid (OA) (0, 10, and 20% w/w) and green tea extract (GTE) (0 and 0.5% w/v) for cheese packaging. Results showed that the opacity, flexibility, and water barrier properties of WPI hydrogel-based film were significantly increased by adding 10% OA. Active release from emulsion-based films was governed by pH and the nature of food model systems. The minimum release occurred in the acidic food model system. After 5 h exposure in the acid food model system, the obtained release from the active film containing OA 0, 10, and 20% was 52.39, 48.97, and 57.24% of incorporated GTE, respectively. The log reduction value (LRV) of active emulsion film against bacteria was significantly affected by the food model system. Moreover, packed lactic coagulated cheese delivered more phenolic compound of GTE than processed spread cheese. Korsmeyer-Peppas model and Weibull with lag were suggested as appropriate models to forecast the release kinetic of GTE.


Asunto(s)
Queso , Ácido Oléico , Proteína de Suero de Leche/química , Embalaje de Alimentos/métodos , Emulsiones , Antioxidantes/química
4.
Food Chem X ; 17: 100547, 2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-36845478

RESUMEN

In this study, optimization of fermentation conditions, and applying endogenous walnut lipase were investigated for the manufacture of a fermented, whey-based beverage containing conjugated linoleic acid (CLA). Among different commercial starter and probiotic cultures, the culture containing Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus showed high potency for CLA synthesis. The fermentation time and the type of walnut oil (lipolyzed or non-lipolyzed) had significant effects on CLA production, as the highest CLA content (36 mg/g fat) was synthesized in the sample containing 1 % lipolyzed walnut oil fermented at 42 °C for 24 h. Moreover, fermentation time had the highest contribution on viable cell counts, proteolysis, DPPH scavenging activity, and final pH. A significant and positive correlation between cell counts and CLA content was also observed (r = +0.823, p < 0.05). This study establishes a cost effective approach for converting cheese whey to a value added beverage enriched with CLA.

5.
J Neuromuscul Dis ; 10(2): 211-225, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36776076

RESUMEN

BACKGROUND: Insufficient amounts of survival motor neuron protein is leading to one of the most disabling neuromuscular diseases, spinal muscular atrophy (SMA). Before the current study, the detailed characteristics of Iranian patients with SMA had not been determined. OBJECTIVE: To describe the key demographic, clinical, and genetic characteristics of patients with SMA registered in the Iranian Registry of SMA (IRSMA). METHODS: IRSMA has been established since 2018, and the demographic, clinical, and genetic characteristics of patients with SMA were recorded according to the methods of treat neuromuscular disease (TREAT-NMD) project. RESULTS: By October 1, 2022, 781 patients with 5q SMA were registered. Of them, 164 patients died, the majority of them had SMA type 1 and died during the first 20 months of life. The median survival of patients with type 1 SMA was 23 months. The consanguinity rate in 617 alive patients was 52.4%, while merely 24.8% of them had a positive family history. The most common type of SMA in live patients was type 3. Morbidities were defined as having scoliosis (44.1%), wheelchair dependency (36.8%), tube feeding (8.1%), and requiring mechanical ventilation (9.9%). Most of the registered patients had a homozygous deletion of SMN1, while the frequency of patients with higher copy numbers of SMN2, was less in more severe types of the disease. Earlier onset of the disease was significantly seen in patients with lower copy numbers of SMN2. The neuronal apoptosis inhibitory protein (NAIP) gene deletion was associated with a higher incidence of more severe types of SMA, higher dependency on ventilators, tube feeding, and earlier onset of the disease. CONCLUSIONS: The IRSMA is the first established Iranian nationwide registry of patients with SMA. Using this registry, decision-makers, researchers, and practitioners can precisely understand the epidemiology, characteristics, and genetics of patients with SMA in Iran.


Asunto(s)
Atrofia Muscular Espinal , Atrofias Musculares Espinales de la Infancia , Humanos , Irán , Homocigoto , Eliminación de Secuencia , Atrofia Muscular Espinal/genética , Atrofias Musculares Espinales de la Infancia/genética , Sistema de Registros
6.
Food Chem ; 250: 180-187, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29412909

RESUMEN

In this study, tomato seeds were obtained as by-products and submitted to fermentation with the proteolytic strain Bacillus subtilis A14h. The resulting peptide mixture was fractionated and purified through different chromatographic steps. Fractions were assayed for antioxidant and angiotensin converting enzyme (ACE)-inhibitory activities and peptides were identified by using nano-liquid chromatography coupled to mass spectrometry in tandem (nLC-MS/MS). Most of the identified peptides were smaller than 1000 Da and had different aromatic and hydrophobic amino acid residues. Their sequences were novel but some of them showed active domains previously reported in other bioactive peptides. The hexapeptide DGVVYY showed an IC50 value of 2 µM in angiotensin-I converting enzyme (ACE-I) inhibitory activity, whereas the pentapeptide GQVPP displayed a 97% of DPPH activity at 0.4 mM. The results revealed that B. subtilis fermentation of tomato by-products could be a good strategy for obtaining added-value peptides that might be used as an ingredient in functional foods and nutraceuticals.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/química , Antioxidantes/química , Bacillus subtilis/metabolismo , Péptidos/química , Solanum lycopersicum/química , Residuos/análisis , Inhibidores de la Enzima Convertidora de Angiotensina/metabolismo , Animales , Antioxidantes/metabolismo , Cromatografía Liquida , Fermentación , Solanum lycopersicum/metabolismo , Solanum lycopersicum/microbiología , Péptidos/metabolismo , Peptidil-Dipeptidasa A/química , Peptidil-Dipeptidasa A/metabolismo , Proteolisis , Conejos , Semillas/química , Espectrometría de Masas en Tándem
7.
Appl Biochem Biotechnol ; 181(1): 48-64, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27461540

RESUMEN

The effects of amino acid composition and peptide molecular mass on ACE-inhibitory and antioxidant activities of protein fragments obtained from tomato waste fermented using Bacillus subtilis were evaluated. The addition of B. subtilis increased the relative amounts of aromatic and positively-charged amino acids which have been described to influence the biological activities of peptide fragments. IC50 values of hydrolysates for ACE-inhibitory and 2, 2'-diphenyl-1-picrylhydrazyl (DPPH) scavenging activities were found to be 1.5 and 8.2 mg/mL, respectively. Size-exclusion chromatography (SEC) pattern of the hydrolysate indicated the breakdown of parent proteins to smaller peptides with molecular weights mainly below 1400 Da. MALDI-TOF mass spectrometry analysis revealed that the highest ACE-inhibitory activity was due to peptides showing molecular mass range 500-800 Da, while the most active antioxidant peptides were found to be mainly at the two different peptide weight ranges 500-800 Da and 1200-1500 Da.


Asunto(s)
Aminoácidos/metabolismo , Inhibidores de la Enzima Convertidora de Angiotensina/aislamiento & purificación , Fermentación , Fragmentos de Péptidos/aislamiento & purificación , Aminoácidos/química , Inhibidores de la Enzima Convertidora de Angiotensina/química , Inhibidores de la Enzima Convertidora de Angiotensina/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Bacillus subtilis/metabolismo , Hidrólisis , Solanum lycopersicum/química , Solanum lycopersicum/metabolismo , Eliminación de Residuos Sanitarios , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Hidrolisados de Proteína/química , Hidrolisados de Proteína/aislamiento & purificación , Hidrolisados de Proteína/metabolismo
8.
Carbohydr Polym ; 152: 253-262, 2016 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-27516271

RESUMEN

In this study, ternary potato starch (PS) bionanocomposite films containing two types of nanoparticles, sodium montmorillonite (MMT), one-dimensional (1D) clay platelets, (3 and 5wt%) and TiO2, three-dimensional (3D) nanospheres, (0.5, 1 and 2wt%), are prepared using solvent casting method. X-ray diffraction (XRD) test confirms the completely exfoliated structure formed in the PS-MMT nanocomposites containing 3 and 5% MMT. The success of the formation of new hydrogen bonds between the hydroxyl groups of starch and nanofillers is confirmed by Fourier transform infrared (FTIR) spectroscopy. Tensile strength (TS), elongation at break (EB), glass transition temperature (Tg), and melting point (Tm) of the films are also enhanced after MMT and TiO2 incorporation. The water vapor permeability (WVP) and the visible, UVA, UVB and UVC lights transmittance decreases upon TiO2 and MMT content increasing. Generally, a synergistic effect is observed between MMT and TiO2 at lower concentrations of MMT.


Asunto(s)
Bentonita/farmacología , Embalaje de Alimentos , Membranas Artificiales , Nanocompuestos/química , Solanum tuberosum/química , Almidón/química , Titanio/farmacología , Bentonita/química , Permeabilidad , Vapor/análisis , Temperatura , Resistencia a la Tracción , Termodinámica , Titanio/química
9.
Int J Biol Macromol ; 89: 256-64, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27132884

RESUMEN

In this research, potato starch and TiO2 nanoparticles (0.5, 1 and 2wt%) films were developed. Influences of different concentrations of TiO2 on the functional properties of nanocomposite films (water-related properties, mechanical characteristics, and UV transmittance) were investigated. XRD, FTIR, and DSC analyses were used to characterize the morphology and thermal properties of the films. The results revealed that TiO2 nanoparticles dramatically decreased the values of water-related properties (water vapor permeability: 11-34%; water solubility: 1.88-9.26%; moisture uptake: 2.15-11.18%). Incorporation of TiO2 led to a slight increment of contact angle and tensile strength, and a decrease in elongation at break of the films. TiO2 successfully blocked more than 90% of UV light, while opacity and white index of the films were enhanced. Glass transition temperature and melting point of the films were positively affected by the addition of TiO2 nanoparticles. The result of XRD study exhibited that due to a limited agglomeration of TiO2 nanoparticles, the mean crystal size of TiO2 increased. Formation of new hydrogen bonds between the hydroxyl groups of starch and nanoparticles was confirmed by FTIR spectroscopy. In conclusion, TiO2 nanoparticles improved the functional properties of potato starch film and extended the potential for food packaging applications.


Asunto(s)
Membranas Artificiales , Nanopartículas del Metal/química , Nanocompuestos/química , Almidón/química , Titanio/química , Embalaje de Alimentos , Humanos , Enlace de Hidrógeno , Permeabilidad , Transición de Fase , Solubilidad , Vapor/análisis , Temperatura , Resistencia a la Tracción
10.
Electron Physician ; 7(8): 1609-12, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26816587

RESUMEN

INTRODUCTION: Central nervous system (CNS) infections are life-threatening diseases caused by viral, bacterial, parasitic and fungal microorganisms. The aim of this study was to determine the accuracy of universal polymerase chain reaction (PCR) for the detection of bacterial meningitis among patients who were referred to Koodakan Hospital in Bandar Abbas because they were suspected of having the disease. METHODS: This study was conducted in 2013 on the patients who were admitted to Bandar Abbas' Koodakan Hospital because they were suspected of having meningitis. A questionnaire, including demographic data, was completed for each patient. Universal PCR, Cerebrospinal fluid (CSF) analysis, and gram staining and cultures were done for all the patients. The data were analyzed using SPSS software. RESULTS: Among the 100 patients studied 59 (59%) were male and 41 (41%) were female. No patient in our study had a positive smear and culture for meningitis. Among the patients with negative smears and cultures six (6%) had positive universal PCR, and 94 (94%) had negative universal PCR. Based on these results, PCR had 95% specificity and 100% negative predictive value for the prediction of meningitis. In 30 patients (30%), the biochemical analysis of CSF were in favor of meningitis. Among the 30 patients, six patients (20%) had positive universal PCR and 24 patients (80%) had negative universal PCR. CONCLUSION: Based on our results, the universal PCR test is useful in the diagnosis of bacterial meningitis in children. We recommend using it in combination with other tests, such as CSF analysis, for diagnosis of bacterial meningitis.

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