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1.
J Food Sci Technol ; 61(6): 1105-1116, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38562603

RESUMO

Nowadays, finding natural and inexpensive resources that can be easily used to make food films has been considered. Despite the widespread use of synthetic resins, natural resins are rarely used. Opopanax resin (OR) was used in this study as a new biosource to prepare the hydrophobic edible film. Ethylcellulose (EC) was blended well with the resin, allowing the formation of a composite film. Film preparation was possible using different amounts of OR and EC. It was interesting that OR had a plasticizing effect on EC film. While using up to 33% w/w glycerol could not produce an elastic EC film, using only 8.5% w/w OR produced a stiff and flexible EC film with lower water sensitivity. Fourier transform infrared (FTIR) spectroscopy analysis showed that the strength of C-O-C and CH bonds in OR + EC film was higher than in EC film. Despite the higher water sensitivity of OR-based composite films than EC-based composite films, they had lower water vapor permeability (WVP) and higher contact angle due to their smoother and more homogeneous film structures with lower porosity, confirmed by scanning electron microscopy (SEM) images. The mechanical properties showed that the film with the highest resin content had the lowest tensile strength (~ 0.4 MPa) and the higher elongation at break (~ 67%) and, therefore, the highest flexibility. The use of natural resins as a biosource is a promising approach in food packaging to prepare hydrophobic films with desirable mechanical properties.

2.
Heliyon ; 10(2): e24917, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38304846

RESUMO

Considering mitigating oxidative degradation and inhibiting microbial proliferation in meat products, incorporating antioxidant and antimicrobial materials is critical to enhance shelf life, maintain quality, and ensure food safety. So, this study aimed to investigate the antimicrobial and antioxidant effects of encapsulated gallic acid on the quality of hamburgers during 30 days of storage. Gallic acid was microencapsulated in tragacanth gum/gelatin complex coacervate, and its encapsulation efficiency was optimized by the response surface method. The optimized encapsulation conditions were 1:4 polymer ratio (tragacanth to gelatin ratio); total polymer content, 0.9 %; pH, 3.5; and gallic acid content, 0.88 %, resulting in a 98 % encapsulation efficiency. The microcapsules were characterized using various techniques, including scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry. 400 ppm encapsulated gallic acid was added to the hamburger formulation, and various microbial properties, chemical analysis (peroxide value (POV) and thiobarbituric acid (TBA)), and sensory properties of the hamburgers were evaluated during storage. Results showed that gallic acid in the hamburgers decreased lipid oxidation from 0.126 to 0.103 mg MAD/kg in the TBA test and 12.73 to 11.03 meq/kg in the POV test during one month of storage. Also, phenolic compounds could prevent the growth and proliferation of spoilage microorganisms by damaging the microorganism cell walls and changing the metabolic processes. So, the amounts of total count and yeast and mold in the treated sample were lower than in the control sample. Significantly, adding encapsulated gallic acid did not negatively affect the flavor or overall evaluation of the samples. Overall, these findings suggested that encapsulated gallic acid is a suitable candidate to maintain chemical, microbial, and sensory characteristics of hamburgers over time.

3.
Curr Res Food Sci ; 7: 100613, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37860146

RESUMO

This study focuses on designing an active bilayer food package film based on polylactic acid (PLA) and bitter vetch seed protein incorporated with Pistacia terebinthus extract (PTE). The effect of PTE on the physicochemical, barrier, structural, mechanical, and antioxidant properties of the active film was determined. Moisture content, water solubility, and water vapor permeability (WVP) of the active films indicated that the addition of PTE increased its suitability for food packaging. FE-SEM micrographs illustrated that the resulting films had a smooth and dense surface, describing a continuous network of protein molecules within the film structure. FTIR analysis displayed the physical interaction between PTE and the film polymer. XRD revealed an increase in the crystallinity of the active films. The resulting active film had a low migration rate (<7%) of phenolic compounds into fatty food simulant. Notably, the addition of PTE significantly (P ≤ 0.05) decreased the tensile strength and Young's modulus (from 15.13 and 315.98 MPa to 14.07 and 254.07 MPa, respectively). Concurrently, there was an increase in the elongation at break of the active films (from 23.19 to 75.60%), indicating higher flexibility compared to control films. Additionally, the incorporation of PTE improved the thermal properties of active films. The antioxidant capacity of the designed films was measured based on their DPPH radical scavenging activity, revealing that the antioxidant capacity of the control film increased from 44.65% to 59.72% in the active film containing 15% PTE. In conclusion, the prepared bilayer film can effectively be used as an active food package for sensitive foods to oxidation.

4.
Int J Biol Macromol ; 237: 124250, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36996955

RESUMO

This study aimed to investigate the segregative interaction of gelatin (G) and tragacanth gum (TG) and the stabilization of their water-in-water (W/W) emulsion by G-TG complex coacervate particles. Segregation was studied at different pHs, ionic strengths and biopolymer concentrations. Results showed that incompatibility was affected by increasing the biopolymer concentrations. So, three reigns were demonstrated in the phase diagram of the salt-free samples. NaCl significantly changed the phase behavior via enhancement of self-association of polysaccharide and changing solvent quality due to the charge screening effect of ions. The W/W emulsion prepared from these two biopolymers and stabilized with G-TG complex particles was stable for at least one week. The microgel particles improved emulsion stability by adsorption to the interface and creating a physical barrier. A fibrous and network-like structure of the G-TG microgels was observed by scanning electron microscopy images suggesting the Mickering emulsion stabilization mechanism. It was confirmed that the bridging flocculation between the microgel polymers led to phase separation after the stability period. Biopolymer incompatibility investigation is a useful tool to obtain beneficial knowledge for preparation new food formulation, especially no contain oil emulsions for low- calorie diets.


Assuntos
Microgéis , Tragacanto , Emulsões/química , Gelatina , Tragacanto/química , Água/química
5.
Int J Biol Macromol ; 223(Pt A): 1420-1431, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36395951

RESUMO

In this study, the surface of the polylactic acid/ethyl cellulose (PLA/EC) blend film was modified by dielectric barrier discharge (DBD) plasma treatment to facilitate the spin-coating of chitosan (CH) and wheat germ bioactive peptides (PEP) obtained from enzymatic hydrolysis of defatted wheat germ protein isolate on the surface of the film. The suitable plasma treatment condition was 5 min at 20 kV according to ATR-FTIR, AFM, SEM, water angle contact, and water solubility results. Increasing the surface roughness and oxygen-containing functional groups (CO and -OH) improved coating by PEP and CH. The PEP-coated film had better antioxidant activity than CH-PEP and CH-coated films. The results of antimicrobial activity demonstrated that PEP-coated film could reduce the growth of gram-negative bacteria (Escherichia coli) and gram-positive bacteria (Staphylococcus aureus). The PEP-coated film had competitive antibacterial properties with CH-coated. Hence, the obtained PEP-coated PLA/EC film could be a promising candidate for antioxidant and antibacterial food packaging.


Assuntos
Quitosana , Gases em Plasma , Quitosana/química , Gases em Plasma/química , Triticum , Embalagem de Alimentos/métodos , Antibacterianos/farmacologia , Antibacterianos/química , Escherichia coli , Água/química , Peptídeos
6.
BMC Med Educ ; 22(1): 184, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35296319

RESUMO

BACKGROUND: Given the importance of spiritual health, resilience and happiness to encounter challenges facing dental students, we aimed to examine these variables, their relationship and the mediating role of resilience between spiritual health and happiness among a group of Iranian dental students in Islamic Azad University of Isfahan. METHODS: In this cross-sectional study, utilizing a stratified sampling method, 150 volunteer dental students in different academic years filled in the Persian version of Spiritual Well-Being scale, the Persian version of Connor-Davidson Resilience Scale, and Isfahan-Fordyce Happiness Inventory. Independent t-test, Kruskal-Wallis test, and Pearson correlation coefficient served for statistical analysis. In addition, we conducted a Structural Equation Modeling analysis. RESULTS: The mean age of the students was 23.43 ± 3.11, and 56% were women. The mean score of spiritual health, resilience, and happiness was 89.27 ± 16.69, 90.19 ± 15.03, and 295.17 ± 65.82, respectively. Spiritual health of a great majority of dental students was upper medium or high (87.3%), most of them had high level of resilience (69.3%), and 55.3% reported medium level of happiness. Spiritual health was directly associated with both happiness and resilience (p <  0.001). Resilience acted as an intermediary variable between spiritual health and happiness (p <  0.001). CONCLUSIONS: Spiritual health was associated with increased happiness, and this relationship was mediated by resilience. Thus, it is recommended to address the issue of spiritual health to those students with lower scores in order to increase their resilience and their level of happiness.


Assuntos
Felicidade , Estudantes de Odontologia , Estudos Transversais , Feminino , Humanos , Irã (Geográfico) , Análise de Classes Latentes
7.
J Food Sci Technol ; 59(3): 1131-1139, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35185212

RESUMO

Gum tragacanth nanoparticles were prepared using a combination of intense ultrasound energy and anti-solvent precipitation methods in this research. Results showed that smaller particles were produced by increasing sonication time. As well, increasing the sonication power led to smaller particles, however, increased aggregation. Accordingly, tragacanth solutions with 0.5 and 1% (w/v) concentrations were prepared and mixed with ethanol (ratio 1:10 v/v) after ultrasound treatment with two different drop-wise and direct methods to investigate the effect of anti-solvent addition method on the precipitation of tragacanth particles. The nanoparticle images showed that the concentration of the 0.5% tragacanth solution and the direct mixing method was suitable for particle production with desirable size (72 ± 10 nm) and uniformity. FTIR, XRD, and STA studies showed that the tragacanth chemical composition did not change, and only its particle size decreased. Investigation of wettability showed a contact angle of 88.9 ± 1.7 degrees for nanoparticles providing partial wetting of the particles at the interface. Investigation of the solution viscosities of 0.5% tragacanth gum and tragacanth nanoparticles showed that the viscosity of the nanoparticles solution was significantly lower than that of the tragacanth (p < 0.05) indicating the intense effect of ultrasonication on this property. It can be concluded that the high viscosity of tragacanth gum is not due to its chemical composition but is due to its complex structure.

8.
Food Chem ; 373(Pt B): 131584, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34799129

RESUMO

The influence of total concentration, biopolymer mixing ratio, and ionic strength on the association of tragacanth gum (TG) and gelatin (G) in the aqueous system during acidification was investigated. The onset of soluble complex formation appeared at pHc, where both biopolymers carried a negative charge. Insoluble complexes were formed at pHφ1 by a further pH decrease, owing to increased interactions between the polymers. The complexes formed at pHφ1 still had partly high negative surface charge. Complex coacervation was observed at pHopt due to the growing size and number of insoluble complexes. The ζ value of the G- TG significantly decreased at pHopt, which was subjected to phase separation. Turbidity decreased at pHφ2 as a result of complex decomposition. The maximum efficiency of complex formation was at the salt-free samples. NaCl reduced critical pHs and complex formation efficiency by screening the ionized groups on the biopolymers.


Assuntos
Gelatina , Tragacanto , Biopolímeros , Concentração de Íons de Hidrogênio , Termodinâmica
9.
J Sci Food Agric ; 102(4): 1353-1362, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34378201

RESUMO

BACKGROUND: Because of the high surface/volume ratio in nanometric size particles, they exhibit novel functional properties in many industries, such as emulsion stabilization. Tragacanth nanoparticles (TNPs) were prepared in this research, applying intense ultrasound energy followed by anti-solvent precipitation in ethanol. RESULTS: Investigation of wettability showed a contact angle of 88.9 ± 1.7° for TNPs, providing partial wetting of the nanoparticles at the oil-water interface. Pickering emulsions were prepared using TNPs at different oil contents. Also, emulsions containing tragacanth gum solution were prepared as control emulsions. Results showed that the viscosity of the emulsions prepared by the TNPs was significantly lower than those of the control emulsions. Microscopic images showed that the size of the emulsion droplets decreased by increasing the nanoparticle concentrations. Evaluation of the stability of the emulsions showed that changes in the average diameter of the emulsion droplets stabilized by nanoparticles were not significant after 1 month of storage at room temperature. In contrast, the size of the droplet of control emulsions increased over the 30 days of storage. Thermal and mechanical stresses confirmed the effect of the concentration of TNPs and the oil ratio on the stability of the emulsions. CONCLUSION: The use of TNPs as a natural biopolymer is a promising approach in emulsion systems to prevent coalescence and increase the stability of the Pickering emulsions. © 2021 Society of Chemical Industry.


Assuntos
Nanopartículas , Tragacanto , Emulsões , Tamanho da Partícula , Solventes , Ultrassom , Água
10.
Anal Chim Acta ; 1186: 339122, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34756273

RESUMO

Developing a rapid and accurate method for tannic acid (TA) detection and measurement is necessary due to its extensive applications in the food industry. In this work, a fluorescence sensor with a low limit of detection was synthesized for TA for the first time. First, amine-modified carbon quantum dots (a-CQDs) with high-quantum yield were synthesized by the hydrothermal method. A layer of molecularly imprinted polymer (MIP) was then placed on a-CQDs by the surface printing method to increase the sensor selectivity. The mechanism of TA detection by the prepared a-CQDs/MIPs was quenching the fluorescence intensity of a-CQDs in the presence of TA due to the transfer of electrons from the TA to the a-CQDs. The linear range of the sensor response was at the TA concentration of 1-200 nmol L-1 and its detection limit was 0.6 nmol L-1 under optimal conditions. Finally, the sensor was used to measure TA in grape juice, green tea, and black tea samples using the recovery method. Recovery values between 97.4 and 103.6% and RSDs less than 3.8% indicated the high potential of the prepared sensor for TA analysis in complex food samples.


Assuntos
Impressão Molecular , Pontos Quânticos , Aminas , Carbono , Limite de Detecção , Polímeros Molecularmente Impressos , Taninos
11.
BMC Oral Health ; 21(1): 409, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34412608

RESUMO

BACKGROUND: Little is known about the effect of illicit drugs on oral health-related quality of life. Our aim was to investigate oral health-related quality among patients with substance use disorders, and its association with dental caries experience and drug use profile. METHODS: Applying a stratified cluster random sampling method, we conducted a cross-sectional study on 267 in-treatment patients with substance use disorders in Isfahan, Iran in 2016. Self-administered questionnaires requested participants' demographics and drug use profile. A trained dental student carried out personal interviews utilizing Oral Impact on Daily Performance (OIDP) instrument. Clinical examinations were conducted to record dental caries experience. T test, ANOVA, pearson and spearman correlation coefficient, and linear regression model served for statistical analysis (p < 0.05). RESULTS: A great majority of the participants reported past use of opium (85%) followed by heroin (42.7%) and amphetamines (20.2%). The most common routes of drug administration were combined routes (44.6%) followed by smoking (36.7%). The mean score of OIDP was 22.4 ± 8.6. As high as 74.1% of the participants reported at least one OIDP impact. The most prevalent OIDP impact was "difficulty eating" (64.8%). The most prevalent cause of the impacts were "dental decay" and "tooth loss". No significant association revealed between OIDP and patients' demographics and drug use profile (p > 0.05). Participants with higher caries experience, reported greater OIDP (p < 0.05). CONCLUSIONS: There is an oral impact on the daily performance of patients with substance use disorders. Patients with higher caries experience reported greater OIDP. Thus, in addition to normative assessment of oral health, clinicians should consider the patients' self-reported oral problems, and the social and mental aspects of oral conditions.


Assuntos
Cárie Dentária , Transtornos Relacionados ao Uso de Substâncias , Atividades Cotidianas , Estudos Transversais , Cárie Dentária/epidemiologia , Humanos , Saúde Bucal , Qualidade de Vida , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Inquéritos e Questionários
12.
Foods ; 10(3)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33804582

RESUMO

Secalin (SCL), the prolamin fraction of rye protein, was chemically lipophilized using acylation reaction by treatment with different amounts of capric acid chloride (0, 2, 4, and 6 mmol/g) to enhance its functional properties. It was shown that SCL lipophilization increased the surface hydrophobicity and the hydrophobic interactions, leading to a reduction in protein solubility and water absorption capacity and to a greater oil absorption. In addition, SCL both emulsifying capacity and stability were improved when the protein was treated with low amount of capric acid chloride. Finally, the foaming capacity of SCL markedly increased after its treatment with increasing concentrations of the acylating agent, even though the foam of the modified protein was found to be more stable at the lower level of protein acylation. Technological application of lipophilized SCL as a protein additive in food preparations is suggested.

13.
J Sci Food Agric ; 100(14): 5260-5268, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32520419

RESUMO

BACKGROUND: Consumption of Spirulina-based functionalized food is usually unpleasant due to its specific sensorial properties. Therefore, Spirulina was encapsulated using alginate and whey protein concentrate (WPC) by emulsification method, and the effect of adding free and microencapsulated Spirulina (MS) to non-fat stirred yogurt was investigated during storage. RESULTS: Scanning electron microscope investigated microcapsules morphology and their mean particle size that was 52 µm, and electrostatic interaction between wall materials was illustrated by Fourier- transform infrared spectroscopy. The microspheres had appropriate encapsulation efficiency (44.54 ± 0.06%). Complete release of Spirulina from the microcapsules was observed in simulated intestinal fluid, which is favorable for Lactobacillus growth in human intestinal tract. Encapsulation caused meaningful differences in colorimetric factors, markedly in L*. Moreover, free and MS were added to yogurt samples, and the results showed that the physicochemical properties (pH, color, viscosity, water holding capacity and susceptibility to syneresis) and sensorial assessment of MS yogurt were positively affected. During the storage, MS yogurt had higher pH value than the others; furthermore, it showed the lowest syneresis and a constant increase in viscosity. Finally, the sensory evaluation results of MS yogurt, in comparison with the free form of Spirulina utilization, indicated improved acceptance of the produced functional food. CONCLUSION: Results showed an obvious impact of encapsulation on the physicochemical properties of yogurt containing MS. The sensory evaluation showed that encapsulation could generally enhance the customer's satisfaction. It can be stated that masking microalgae color and flavor by microencapsulation could be used for dairy products fortification by microalgae. © 2020 Society of Chemical Industry.


Assuntos
Alginatos/química , Aditivos Alimentares/análise , Spirulina/química , Proteínas do Soro do Leite/química , Iogurte/análise , Animais , Bovinos , Manipulação de Alimentos , Armazenamento de Alimentos , Alimento Funcional/análise , Humanos , Sensação , Viscosidade
14.
Int J Biol Macromol ; 159: 1031-1047, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32439450

RESUMO

The present research was concerned with preparation of mesoporous starch (MPS) as a carrier for genistein, a model of poorly water-soluble phytoestrogen isoflavone; and exploration of the impact of different fabrication parameters on structural and loading properties. MPS is considered as a highly porous biomaterial which typically possesses nanometer-sized porous microstructure and low density, providing a large effective specific surface area (SSA) and hydrophilic surface to improve solubility, stability and bioavailability of poorly water-soluble active agents. To fabricate MPS, various concentrations (8-14% w/v) of starch from different sources (corn, potato and tapioca) was used for gel formation and the successive solvent exchange process was performed with use of various ethanol concentrations (40-70% v/v), which were then dried by different techniques (rotary vacuum evaporation, microwave and freeze drying). MPS quality attributes such as SSA, total porous volume, BJH pore diameter and swelling ratio were determined and effects of the fabrication parameters were investigated using L9-Taguchi orthogonal array design. The results indicate that second order polynomial regression models were well fitted for all response variables. Interestingly, the starch components greatly influenced physical properties of MPS. Also, the drying type and ethanol concentration altered significantly the model equations. The overall best fabrication condition (14% corn starch, 100% ethanol concentration in aging step and rotary vacuum drying) resulted in favorable MPS preparation with mean size of 105.4 nm and unimodal distribution. In the next step, genistein was encapsulated in MPS microstructure at different ratios, resulting in high loading capacity and efficiency (44.71% and 79.9%, respectively) at 1:1 weight ratio. Equilibrium adsorption isotherm of genistein was evaluated also by four different kinetics models including Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin isotherms. The experimental data were found to be fitted well to the Langmuir model (R2 = 0.989). According to the electron microscopy and XRD analysis, the degree of genistein crystallinity lowered remarkably after the impregnation in to MPS, indicating improved solubility. In-vitro release profile of genistein from MPS in the simulated gastrointestinal buffer solutions (pH 1.2 and 6.8) demonstrated that incorporating genistein into the MPS enhanced the dissolution rate compared with genistein powder. Release kinetic data were fitted to the Higuchi model (R2 = 0.98), indicating diffusion-controlled release mechanism. Altogether, well-tuned MPS fabrication method can be utilized for an efficient encapsulation and dissolution enhancement of poorly soluble phytochemicals, such as genistein.


Assuntos
Genisteína/administração & dosagem , Nanocápsulas/química , Fitoestrógenos/administração & dosagem , Amido/química , Liberação Controlada de Fármacos , Genisteína/química , Fitoestrógenos/química , Porosidade , /química
15.
BMC Oral Health ; 19(1): 5, 2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30616605

RESUMO

BACKGROUND: In addition to numerous general health problems, drug dependents manifest various oral health disorders. Our aim was to investigate the oral health status and its determinants among in-treatment opiate dependents. METHODS: As part of a comprehensive cross-sectional survey on opiate dependents admitted to methadone maintenance centers in Tehran, Iran, we conducted a clinical study in two centers from different socioeconomic areas. A trained dentist conducted face to face interviews and clinical oral examinations based on World Health Organization (WHO) criteria for Decayed, Missing, Filled Teeth (DMFT) index and Community Periodontal Index (CPI) on volunteer patients. Student's t-test, Mann-Whitney U, Kruskal Wallis, and Chi2 tests, in addition to linear and logistic regression models served for statistical analysis (p < 0.05). RESULTS: A total of 217 patients (98% men), with a mean age of 43.6 years (SD 12.3) participated in the study. Opium was the main drug of abuse reported by 70% of the participants followed by crystalline heroin (22%). Of the participants, 24.4% were totally edentulous. The mean DMFT score of participants was 20.3 (SD 7.8). Missing teeth comprised the main part of the index followed by decayed and filled teeth. Older patients (p < 0.001) and the patients with a lower socioeconomic status (p = 0.01) had higher DMFT scores. None of the dentate patients had a healthy periodontium. Maximum CPI mostly consisted of shallow pockets (66%) followed by calculus in 15%, deep pockets in 11%, and bleeding in 8% of the participants. Older participants (p = 0.02) and those who started drug abuse at a younger age (p = 0.01) were more likely to develop periodontal pockets. CONCLUSIONS: Opiate dependents had a poor oral health status in terms of the dentition status and periodontal health. Missing teeth comprised the main part of their dental caries history and none had a healthy periodontium. Oral health care should be integrated into the package of general health services available in treatment centers.


Assuntos
Cárie Dentária/epidemiologia , Transtornos Relacionados ao Uso de Opioides/complicações , Saúde Bucal , Adolescente , Adulto , Estudos Transversais , Índice CPO , Cárie Dentária/etiologia , Feminino , Nível de Saúde , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Índice Periodontal , Bolsa Periodontal/epidemiologia , Bolsa Periodontal/etiologia , Prevalência , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
16.
Int J Biol Macromol ; 124: 946-954, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30521891

RESUMO

This research aimed to optimize the polysaccharides extraction of oleaster fruit and then to investigate the physicochemical and functional properties of extracted polysaccharides. Temperature, water to dry matter ratio, time, and alcohol ratio were considered as variables. Purity of extracted polysaccharides was considered as the response. Optimization of polysaccharides extraction from full grain oleaster showed that all variables had effects on the purity of extracted polysaccharides alone or by interacting with other variables. The results showed that the temperature, 60 °C; water to dry matter ratio, 53:1 (V/W); time, 5 h; and alcohol ratio of 2.9 (V/V) were the best conditions for achieving the highest purity in extracted polysaccharides. The extracted polysaccharides had the potential of emulsion formation with high stability; however, foamability was not observed in this polysaccharide. In addition, the solubility of polysaccharide powder was high, and it increased with an increase in temperature, which resulted in a decrease in water absorption indicating the effect of heat on the structure and the amount of water absorption of extracted polysaccharides. The results obtained from FTIR confirmed the polysaccharide nature of extracted powder, and the X-ray diffraction pattern of extracted polysaccharides showed its semi-crystalline structure.


Assuntos
Elaeagnaceae/química , Frutas/química , Extração Líquido-Líquido/métodos , Polissacarídeos/química , Emulsões , Etanol/química , Análise Fatorial , Extratos Vegetais/química , Polissacarídeos/isolamento & purificação , Pós , Solubilidade , Solventes/química , Temperatura , Viscosidade , Água/química
17.
Ultrason Sonochem ; 42: 585-593, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29429707

RESUMO

Inulin, rice bran oil and rosemary essential oil were used to produce high quality emulsion filled gel (EFG) using ultrasonic radiation. Response surface methodology was used to investigate the effects of oil content, inulin content and power of ultrasound on the stability and consistency of prepared EFG. The process conditions were optimized by conducting experiments at five different levels. Second order polynomial response surface equations were developed indicating the effect of variables on EFG stability and consistency. The oil content of 18%; inulin content of 44.6%; and power of ultrasound of 256 W were found to be the optimum conditions to achieve the best EFG stability and consistency. Microstructure and rheological properties of prepared EFG were investigated. Oil oxidation as a result of using ultrasonic radiation was also investigated. The increase of oxidation products and the decrease of total phenolic compounds as well as radical scavenging activity of antioxidant compounds showed the damaging effect of ultrasound on the oil quality of EFG.


Assuntos
Inulina/química , Óleo de Farelo de Arroz/química , Sonicação , Compostos de Bifenilo/química , Estabilidade de Medicamentos , Emulsões , Sequestradores de Radicais Livres/química , Lipídeos/química , Oxirredução , Picratos/química , Rosmarinus/química
18.
Int J Biol Macromol ; 103: 640-647, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28528002

RESUMO

In this study iron salt (FeSO4·7H2O) was microencapsulated in gum tragacanth hydrogel using solvent evaporation method. Three significant parameters (ferrous sulfate content, content of gum tragacanth, and alcohol to mixture ratio) were optimized by response surface methodology to obtain maximum encapsulation efficiency. Ferrous sulfate content, 5%, content of gum tragacanth, 22%, and alcohol to mixture ratio, 11:1 was determined to be the optimum condition to reach maximum encapsulation efficiency. Microstructure of iron microcapsules was thoroughly monitored using scanning electron microscopy (SEM). The microphotographs indicated two distinct crystalline and amorphous structures in the microcapsules. This structure was confirmed by X-ray diffraction (XRD) pattern of microcapsules. Fourier transform infrared (FTIR) spectra of iron microcapsules identified the presence of iron in the tragacanth microcapsules. The average size of microcapsules was determined by particle size analyzer. Release assessment of iron in simulated gastric fluid showed its complete release in stomach which is necessary for its absorption in duodenum. However, the use of encapsulated iron in gum tragacanth in watery foods is rather recommended due to the fast release of iron in water.


Assuntos
Composição de Medicamentos/métodos , Ferro/química , Solventes/química , Tragacanto/química , Álcoois/química , Cápsulas , Compostos Ferrosos/química , Tamanho da Partícula , Propriedades de Superfície , Volatilização , Água/química
19.
Int J Biol Macromol ; 95: 689-695, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27919814

RESUMO

In this study nanofibers were prepared via the electrospinning technique by basil seed mucilage (BSM) as a new source of hydrocolloid. Polyvinyl alcohol (PVA) was used as an aiding agent. Viscosity and electrical conductivity of BSM/PVA solutions of different volume ratios (100:0, 80:20, 60:40, 40:60, 20:80 and 0:100) were in the range of 790-1300cP and 745-2140µS/cm, respectively. Morphology of nanofibers were investigated using scanning electron microscopy (SEM) that showed an average diameter range of 179-390nm. Fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) studies were used to analysis chemical composition, crystalline structure and thermal characteristics of nanofibers. The characteristic picks of basis seed mucilage were found in BSM/PVA nanofibers. The crystalline index of BSM, PVA and BSM/PVA nanofibers were 54, 35 and 43%, respectively. The BSM based nanofibers can be used for different applications such as bioactive encapsulation and packaging film production.


Assuntos
Fenômenos Químicos , Eletricidade , Ocimum basilicum/química , Extratos Vegetais/química , Sementes/química , Condutividade Elétrica , Álcool de Polivinil/química , Viscosidade
20.
J Biomater Sci Polym Ed ; 27(16): 1631-44, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27540886

RESUMO

Calcium alginate hydrogel beads were used to encapsulate lemon balm extract. Chitosan layer was used to investigate the effect of hydrogel coating. To determine the interactions of antioxidant compounds of extract with encapsulation materials and its stability, microstructure of hydrogel beads was thoroughly monitored using scanning electron microscopy and Fourier transform infrared (FTIR). Total polyphenols content and antiradical activity of lemon balm extract were also evaluated before and after encapsulation. Three significant parameters (lemon balm extract, sodium alginate, and calcium chloride concentrations) were optimized by response surface methodology to obtain maximum encapsulation efficiency. The FTIR spectra showed no interactions between extract and polymers as there were no new band in spectra of alginate hydrogel after encapsulation of active compounds of lemon balm extract. The antioxidant activity of lemon balm extract did not change after encapsulation. Therefore, it was found that alginate is a suitable material for encapsulation of natural antioxidants. Sodium alginate solution concentration, 1.84%, lemon balm extract concentration, 0.4%, and calcium chloride concentration, 0.2% was determined to be the optimum condition to reach maximum encapsulation efficiency.


Assuntos
Alginatos/química , Antioxidantes/química , Portadores de Fármacos/química , Hidrogéis/química , Melissa/química , Extratos Vegetais/química , Cápsulas , Liberação Controlada de Fármacos , Ácido Glucurônico/química , Ácidos Hexurônicos/química
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