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1.
Nanomaterials (Basel) ; 13(14)2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37513139

RESUMO

Full and partial restorations in dentistry must replicate the characteristics of the patient's natural teeth. Materials must have good mechanical properties and be non-toxic and biocompatible. Microbes, which can form biofilms, are constantly in contact with restorations. In this study, we investigate how well Candida albicans adheres to a polymethyl methacrylate (PMMA) resin base with gold (Au) nanoparticles. We synthesized Au nanoparticles and characterized them. The average size of Au nanoparticles embedded in PMMA was 11 nm. The color difference ΔE between PMMA and PMMA/Au composites was 2.7 and was still esthetically acceptable to patients. PMMA/Au surfaces are smoother and more hydrophilic than pure PMMA surfaces, and the isoelectric point of both types of surfaces was 4.3. Above the isoelectric point, PMMA/Au surfaces are more negatively charged than PMMA surfaces. The added Au nanoparticles decreased the tensile strength, while the hardness did not change significantly. Adhesion measurements showed that PMMA surfaces modified with Au nanoparticles reduced the extent of microbial adhesion of Candida albicans.

2.
Materials (Basel) ; 14(22)2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34832279

RESUMO

Orthotic and prosthetic materials should have good mechanical and antibacterial properties. Therefore, in our study, we consider four common foamed closed-cells and two solid polymeric materials regarding their mechanical behaviour and tendency for bacterial adhesion. For all materials, the surface roughness, hydrophobicity, zeta potential, tensile properties, hardness and CIE color parameters were measured. We found that foamed polymeric materials have higher roughness, higher hydrophobicity, lower Young's modulus, lower maximum tensile strength and lower hardness than solid materials. Bacterial adhesion test measurements based on observation by scanning electron microscopy show much a lower adhesion extent of S. aureus on solid materials than on foamed materials. The measured biophysical properties could be the key data for users to select the optimal materials.

3.
Foods ; 10(8)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34441510

RESUMO

In this study, Pelvetia canaliculata L. macroalga, collected from the Atlantic Portuguese coast, was used as a source of bioactive compounds, mostly antioxidants, to incorporate them in sunflower oil with the aim of increasing its biological value and oxidative stability. The lyophilized alga was added to the oil, and ultrasound-assisted extraction (UAE) was performed. Algae concentration and UAE time varied following a central composite rotatable design (CCRD) to optimize extraction conditions. The following parameters were analyzed in the oils: oxidation products, acidity, color, chlorophyll pigments, carotenoids, flavonoids, total phenolic content, antioxidant activity by DPPH (2,2-diphenyl-1-picrylhydrazyl) and FRAP (ferric reducing antioxidant power) assays, and sensory analysis. Extraction conditions did not affect the acidity and the amount of oxidation products in the oil. Chlorophylls and carotenoid contents increased with algae concentration, while flavonoid extraction did not depend on algae content or UAE time. Total phenolics in the oil were highly related only to FRAP antioxidant activity. Storage experiments of supplemented oil (12.5% algae; 20 min UAE) were carried out under accelerated oxidation conditions at 60 °C/12 days. Antioxidant activity (FRAP) of supplemented oil was 6-fold higher than the value of non-supplemented oil. Final samples retained 40% of their initial antioxidant activity. The presence of algae extracts contributed to the increased oxidative stability of sunflower oil.

4.
Plants (Basel) ; 10(2)2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33562107

RESUMO

The response of grafted bell pepper plants (Capsicum annuum L. var. grossum (L.) Sendtn.) to salt stress was investigated by analyzing the photosynthetic traits and mineral content of the plants and the metabolic composition of the fruit. The bell pepper variety "Vedrana" was grafted onto the salt-tolerant rootstock "Rocal F1" and grown at two salinities (20 mM and 40 mM NaCl) and control (0 mM NaCl) during the spring-summer period. On a physiological level, similar stomatal restriction of photosynthesis in grafted and ungrafted plants indicated that grafting did not alleviate water balance disturbances under increased salt exposure. Measurements of midday water potential did not show improved water status of grafted plants. The similar metabolic changes in grafted and ungrafted plants were also reflected in similarly reduced fruit yields. Thus, this grafting did not reduce the risk of ionic and osmotic imbalance in pepper plants grown under moderate salt treatment. Changes in the biochemical profiles of the pepper fruit were seen for both added-salt treatments. The fruit phenolic compounds were affected by rootstock mediation, although only for the July harvest, where total phenolics content increased with 40 mM NaCl treatment. Fruit ascorbic acid content increased with the duration of salt stress, without the mediation of the rootstock. The high salt dependence of this quality trait in pepper fruit appears to lead to more limited rootstock mediation effects.

5.
Nutrients ; 13(1)2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33445809

RESUMO

Consumption of trans fatty acids (TFAs) has been unequivocally linked to several adverse health effects, with the increased risk of cardiovascular disease being one of the most well understood. To reduce TFA-related morbidity and mortality, several countries have imposed voluntary or mandatory measures to minimize the content of industrial TFAs (iTFAs) in the food supply. In 2018, Slovenia introduced a ban on iTFAs on top of preceding voluntary calls to industry to reduce its use of partially hydrogenated oils (PHOs) as the main source of iTFAs. To investigate the consumption of TFAs, data available from the nationally representative dietary survey SI.Menu were analyzed. The survey consisted of two 24-h non-consecutive day recalls from 1248 study participants from three age groups (10-17, 18-64, 65-74 years old), combined with socio-demographic, socio-economic, and lifestyle parameters. The analyses demonstrated that, on average, TFAs accounted for 0.38-0.50% of total energy intake (TEI). However, 13% of adolescents, 29.4% of adults, and 41.8% of the elderly population still consumed more than 0.50% TEI with TFAs. The main sources of TFAs in the diet were naturally present TFAs from butter, meat dishes, and meat products, regardless of the age group. Results indicate that following the reformulation activities, the major sources of TFAs in the diets of the Slovenian population now represent foods which are natural sources of TFAs.


Assuntos
Doenças Cardiovasculares , Gorduras na Dieta/efeitos adversos , Ingestão de Energia , Ácidos Graxos trans/efeitos adversos , Adolescente , Adulto , Idoso , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Eslovênia/epidemiologia
6.
Public Health Nutr ; 24(1): 12-21, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32718382

RESUMO

OBJECTIVE: Consumption of trans-fatty acids (TFA) is a well-established risk factor for CVD morbidity and mortality. Our objective was to investigate TFA levels in Slovenian food supply. DESIGN: Cross-sectional study. SETTING: Selected foods (n 282) were purchased in Slovenia (2016), and the TFA content was determined. The sample included pre-packed foods with/without declared partially hydrogenated vegetable oils (PHO), as well as non-pre-packed foods. A sales-weighting approach was used to ponder different market shares of the products. RESULTS: While the majority of the investigated samples had low levels of TFA, up to 6·8 g of TFA per 100 g of food was observed in certain foods. Within pre-packed foods (n 207), the highest proportion of samples with high TFA levels was found among cookies with labelled PHO: 69 % (n 18) would exceed European Union regulatory TFA limit (2 g industrial TFA per 100 g of fats), which will be implemented in April 2021. Among the investigated non-pre-packed foods (n 75), only croissants contained notable TFA levels (mean 0·90 (sd 0·97); maximum 3·3 g/100 g), with about half of the samples exceeding 2 g TFA per 100 g of fats. CONCLUSIONS: In 2016, some foods in Slovenian food supply still contained notable amounts of TFA. Foods with listed PHO as an ingredient were usually higher in TFA as compared with foods not labelled to contain PHO. Biscuits were identified as the most concerning category of pre-packed foods, while croissants contained highest levels of TFA within non-pre-packed foods.


Assuntos
Análise de Alimentos , Ácidos Graxos trans , Comércio , Estudos Transversais , Gorduras na Dieta/análise , Abastecimento de Alimentos , Humanos , Eslovênia , Ácidos Graxos trans/análise
7.
Sensors (Basel) ; 20(20)2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33076361

RESUMO

Due to the presence of bioactive compounds, fruits are an essential part of people's healthy diet. However, endogenous ethylene produced by climacteric fruits and exogenous ethylene in the microenvironment could play a pivotal role in the physiological and metabolic activities, leading to quality losses during storage or shelf life. Moreover, due to the variety of fruits and complex scenarios, different ethylene control strategies need to be adapted to improve the marketability of fruits and maintain their high quality. Therefore, this study proposed an ethylene dynamic monitoring based on multi-strategies control to reduce the post-harvest quality loss of fruits, which was evaluated here for blueberries, sweet cherries, and apples. The results showed that the ethylene dynamic monitoring had rapid static/dynamic response speed (2 ppm/s) and accurately monitoring of ethylene content (99% accuracy). In addition, the quality parameters evolution (firmness, soluble solids contents, weight loss rate, and chromatic aberration) showed that the ethylene multi-strategies control could effectively reduce the quality loss of fruits studied, which showed great potential in improving the quality management of fruits in the supply chain.

8.
Foods ; 9(4)2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32283874

RESUMO

This study presents the results of conventional aqueous (CE) and non-conventional ultrasound-assisted (UAE) extractions of polyphenolic compounds from lees extracts of red wine varieties (Merlot and Vranac). The effect of ultrasound extraction time (t, s), and amplitude (A,%) from a 400 W ultrasound processor with different ultrasonic probes diameters (Ds, mm) on the amount and profile of polyphenolic compounds in the obtained extracts was investigated and compared to CE. The optimal conditions resulting in maximum extraction of phenolic compounds were: Probe diameter of 22 mm, amplitude 90% and extraction time for Vranac wine lees 1500 s and for Merlot wine lees extraction time of 1361 s. UAE proved to be significantly more effective in enhancing the extraction capacity of trans-resveratrol glucoside (30.57% to 300%), trans-resveratrol (36.36% to 45.75%), quercetin (39.94% to 43.83%), kaempferol (65.13% to 72.73%), petunidin-3-glucoside (41.53% to 64.95%), malvidin-3-glucoside (47.63% to 89.17%), malvidin-3-(6-O-acetyl) glucoside (23.84% to 49.74%), and malvidin-3-(6-O-p-coumaroyl) glucoside (26.77% to 34.93%) as compared to CE. Ultrasound reduced the extraction time (2.5-fold) and showed an increase of antioxidant potential by 76.39% (DPPH) and 125.83% (FRAP) compared to CE.

9.
Food Chem Toxicol ; 136: 111109, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31904471

RESUMO

Organic crop production has become a highly attractive way of production over the world and thus the need for robust analytical techniques for their authentication. The main aim of this study is to identify appropriate biomarkers to discriminate between organic and conventionally grown chicory. Chicory is an appreciated leafy vegetable among producers and consumers, especially due to its undemanding cultivation and content of bioactive substances. Six different fertility management practices (control, two organic, two mineral, and a combination of organic and mineral fertilizers) were used to produce five chicory cultivars in a glasshouse pot experiment. Analysis of bioactive compounds, nitrogen assimilation, multi-elemental profiling and stable isotope ratio determination of carbon (C), nitrogen (N) and sulphur (S) were performed to differentiate between organic and conventional production. In this study, nitrogen isotopes are found to be an excellent way of identifying organically produced chicory of a different variety with the highest δ15N values. Conversely, the same samples had the lowest δ34S values indicating that also stable isotopes of S could be used as a marker for the authentication of organic production.


Assuntos
Cichorium intybus/química , Cichorium intybus/crescimento & desenvolvimento , Agricultura , Isótopos de Carbono/análise , Análise Discriminante , Alimentos Orgânicos/análise , Isótopos de Nitrogênio/análise , Agricultura Orgânica , Folhas de Planta/química , Folhas de Planta/crescimento & desenvolvimento , Isótopos de Enxofre/análise , Verduras/química , Verduras/crescimento & desenvolvimento
10.
BMC Plant Biol ; 20(1): 36, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959114

RESUMO

BACKGROUND: Chicory (Cichorium intybus L.) is a traditional European crop that is highly appreciated for its contents of bioactive compounds, especially phenolics, which have high antioxidant activities. Among other factors, agricultural practice might affect the contents of these bioactive compounds, which are also important from a nutritional point of view, and affect the shelf-life. RESULTS: The antioxidant potential (AOP) of chicory plants treated with different fertilisers was investigated in vitro using DPPH radical scavenging and in vivo using the yeast Saccharomyces cerevisiae. Additionally, total phenolics content (TPC) was evaluated using Folin-Ciocalteu reagent, and total flavonoids content (TFC) using the aluminium chloride method. Four different chicory cultivars were included: 'Treviso', 'Verona' and 'Anivip' as red cultivars; and 'Castelfranco' as a red-spotted cultivar. These were grown in pots under controlled glasshouse conditions using organic and/or mineral fertilisers. The combination of organic and mineral fertilisers during red chicory growth resulted in significantly higher in-vitro and in-vivo AOPs compared to the control. For the red-spotted cultivar 'Castelfranco', this combined organic and mineral fertilisation decreased AOPs in vitro and increased AOPs in vivo. Among the cultivars examined, 'Castelfranco' treated with combined organic plus mineral fertilisers showed the highest AOP in vivo, accompanied by the lowest TPC and TFC. CONCLUSIONS: These data show that application of different fertilisers has different impacts on red and red-spotted chicory cultivars in terms of TFC and TPC, which for red-spotted chicory resulted in different AOPs in vitro and in vivo. The in-vitro AOP is well reflected in the in-vivo AOP for the red chicory cultivars, but less so for the red-spotted cultivar 'Castelfranco'. Based on the in-vivo AOPs for these chicory cultivars analysed, the combined organic plus mineral fertiliser treatment is recommended.


Assuntos
Antioxidantes/administração & dosagem , Cichorium intybus/metabolismo , Fertilizantes/análise , Antioxidantes/metabolismo , Cichorium intybus/genética , Cichorium intybus/crescimento & desenvolvimento , Fertilizantes/classificação
11.
Food Chem ; 230: 241-249, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28407907

RESUMO

To enhance storage life and post-storage quality of fresh goji berries, three treatments with lecithin (1, 5, 10g·L-1) and two storage times (8, 16days) were evaluated. The significant effects on the physiological and biochemical parameters were varied. 1g·L-1 lecithin showed its main effects after 8days of storage by reduction in total weight loss and decay, SSC/TA ratio (also at 16days), and chlorophyll content and with highest scores of sensory attributes (also at 16days). 5g·L-1 lecithin showed its main effects after 16days of storage: highest SSC, highest TA (also at 8days), highest TPC, only significant reduction in DPPH antioxidant activity, and highest total flavonoid content. 10g·L-1 lecithin showed its main effects after 8days of storage with highest SSC, chlorophyll content, total flavonoid, DPPH, and ABTS antioxidant activity (also at 16days), but with least scores of sensory attributes.


Assuntos
Antioxidantes/química , Frutas/química , Lecitinas/química , Lycium/química , Antioxidantes/análise , Armazenamento de Alimentos , Lecitinas/análise , Oxirredução
12.
Food Sci Nutr ; 5(1): 160-170, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28070327

RESUMO

Celtis australis is a deciduous tree commonly known as Mediterranean hackberry or the European nettle tree. The fruit of hackberry are seldom used for nutritional purposes. The nutritional and physicochemical properties of ripe hackberry fruit from Istria (Marasi village near Vrsar, Croatia) were determined, including water, total fiber, protein, vitamin, mineral, and phenolic contents. This analysis demonstrates that the hackberry fruit is a valuable source of dietary fiber, protein, and vitamins, and of pigments such as lutein, ß-carotene, zeaxanthin, and tocopherols. The seasonal differences associated with the different growth stages for the element composition, total phenolic content, and phenolic profile were also determined for hackberry mesocarp and leaves. Water and ethanol extracts were prepared from mesocarp and leaves harvested at different growth stages and their phenolic profiles and antioxidant and antimicrobial activities were investigated. This study demonstrates that water and ethanol extracts of hackberry fruit and leaves collected at different growth stages contain epicatechin, gallic acid, vanillic acid, 3,4-dihydroxybenzaldehyde, delphinidin-3,5-di-O-glucoside, cyanidin-3,5-di-O-glucoside, and pelargonidin-3,5-di-O-glucoside. They also show some antimicrobial and antifungal activities. Further studies are needed to identify and define the active ingredients of these hackberry leaf ethanol extracts.

13.
Food Technol Biotechnol ; 54(2): 228-235, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27904413

RESUMO

The objective of this study is to investigate the effects of irradiation from light-emitting diodes (LEDs) on several fruits during storage. To improve storage and increase the contents of some bioactive compounds, apple, tomato and red bell pepper fruits were exposed to yellow light emitted from the diodes at 590 nm. The contents of ascorbic acid, total phenolics, total flavonoids and several pigments were investigated, along with the antioxidant potential. The colour parameters (L*, a* and b*) and firmness of the fruit were also determined. After 7 days of LED light irradiation, there was significantly higher total phenolic content and antioxidant potential in apple peel extracts. The irradiated fruit of tomato had significantly higher levels of total phenolic compounds, and the fruit of red bell pepper had significantly higher antioxidant potential. LED light had no effects on the colour parameters, although there was a tendency to accelerate colour development. Apple fruit irradiated with LED light was significantly less firm. Among twelve analysed pigments, significantly more ß-carotene was detected in LED light-irradiated apple and bell pepper fruit, more α-tocopherol and γ-tocopherol in bell pepper fruit, and more lutein in apple peel and bell pepper fruit. The applied LED light slightly accelerated the ripening of the studied fruit, and affected the synthesis of some of the secondary metabolites.

14.
Food Technol Biotechnol ; 53(3): 298-306, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27904361

RESUMO

Today, obesity is one of the major health problems, a so-called epidemic of the developed world. Obesity arises through an imbalance between energy intake and energy expenditure, so it is important for products to have a balanced nutritional composition. The aim of this study is to prepare high-protein pasta with high nutritional quality, with emphasis on its amino acid composition, as ordinary durum pasta lacks lysine and threonine. Ordinary durum wheat pasta contains, on average, 77% carbohydrate, and can have even less than 10% protein. It is therefore often excluded from normal energy-restricted diets, and especially from low-carbohydrate diets. In this study pasta that can satisfy the nutritional requirements of a low-carbohydrate diet and is suitable for daily use was developed and evaluated. Protein-enhanced pasta was produced by adding high amounts of plant protein extract (40% dry matter) without (plain high-protein pasta) or with 3% dried spinach powder (high-protein spinach pasta) to durum wheat semolina. According to the sensory analysis data, the addition of 40% of plant protein extract satisfied sensory and nutritional requirements, allowing further development and evaluation for possible marketing. This analysis shows that these high-protein neutral and spinach pasta contain 36.4 and 39.6 g of protein per 100 g of dry mass, 12.07 and 14.70 g of total essential amino acids per 100 g of dry mass, and a high content of branched-chain amino acids, i.e. 5.54 and 6.65 g per 100 g of dry mass, respectively. This therefore represents a true alternative to durum wheat pasta for low-carbohydrate diets.

15.
Food Chem ; 166: 507-513, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25053087

RESUMO

Chicory (Cichorium intybus L.) is a typical Mediterranean vegetable, and it shows great morphological diversity, including different leaf colours. Five cultivars commonly produced in Slovenia ('Treviso', 'Verona', 'Anivip', 'Castelfranco', 'Monivip') were grown in pots under controlled conditions in a glasshouse, with organic and/or mineral fertilizers administered to meet nitrogen requirements. HPLC analysis was carried out to study the phenolic compositions of the leaves. A total of 33 phenolic compounds were extracted from these chicory leaves and were quantitatively evaluated in an HPLC-DAD-based metabolomics study. Among the cultivars, the highest TPC was seen for 'Treviso' (300.1 mg/100 g FW), and the lowest, for 'Castelfranco' (124.9 mg/100g FW). Across the different treatments, the highest TPC was in the control samples (254.3 mg/100 g FW), and the lowest for the organic (128.6 mg/100 g FW) and mineral fertilizer (125.5 mg/100 g FW) treatments. The predominant phenolic compounds in all of the samples were hydroxycinnamic acids, including chlorogenic and cichoric acid. Fertilizer administration provides a discriminant classification of the chicory cultivars according to their phenolic compounds.


Assuntos
Cichorium intybus/química , Fertilizantes/análise , Fenóis/análise , Cichorium intybus/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/análise , Análise Discriminante , Minerais , Folhas de Planta/química , Análise de Componente Principal
16.
J Agric Food Chem ; 61(47): 11355-62, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24191675

RESUMO

Model vegetable oil mixtures with significantly different basic oil quality indices (free fatty acid, iodine, and Totox values) were prepared by adding oleic acids, synthetic saturated triglycerides, or oxidized safflower oil ( Carthamus tinctorius ) to the oleic type of sunflower oil. Dielectric constants, dielectric loss factors, quality factors, and electrical conductivities of model lipids were determined at frequencies from 50 Hz to 2 MHz and at temperatures from 293.15 to 323.15 K. The dependence of these dielectric parameters on basic oil quality indices was investigated. Adding oleic acids to sunflower oil resulted in lower dielectric constants and conductivities and higher quality factors. Reduced iodine values resulted in increased dielectric constants and quality factors and decreased conductivities. Higher Totox values resulted in higher dielectric constants and conductivities at high frequencies and lower quality factors. Dielectric constants decreased linearly with temperature, whereas conductivities followed the Arrhenius law.


Assuntos
Óleos de Plantas/química , Verduras , Compostos de Anilina/análise , Condutividade Elétrica , Eletricidade , Ácidos Graxos não Esterificados/análise , Qualidade dos Alimentos , Iodo/análise , Ácido Oleico/química , Óleos de Plantas/análise , Óleo de Girassol , Triglicerídeos/química
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