Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Plants (Basel) ; 13(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38674528

RESUMO

An investigation of the ultrasound-assisted extraction (UAE) of polyphenol-rich aqueous extracts from blackberry, chokeberry and raspberry pomaces was carried out. The aim of the study was to choose optimal conditions for UAE in order to obtain extracts rich in phenolic compounds. The optimization was carried out based on response surface methodology. The variable conditions were amplitude of ultrasound wave and extraction time, whereas responses were total polyphenol content and antioxidant capacity. Based on the ANOVA analysis, mathematical models were fitted and verified. The most effective conditions of amplitude and time were 98% and 5.00 min, 78% and 10.32 min and 90% and 11.56 min for blackberry pomace, chokeberry pomace and raspberry pomace, respectively. The actual results obtained in optimized conditions were comparable to the results predicted by the models. Additionally, the anthocyanin content in extracts was determined in the high-performance liquid chromatography assay. It was proven that response surface methodology could be a useful tool in the optimization of UAE processes for obtaining polyphenol-rich extracts from berry fruit pomaces.

2.
Artigo em Inglês | MEDLINE | ID: mdl-37646889

RESUMO

Due to the growing demand for natural carotenoids, researchers have been searching for strains that are capable of efficient synthesis of these compounds. This study tested 114 red yeast strains collected from various natural environments and food specimens in Poland. The strains were isolated by their ability to produce red or yellow pigments in rich nutrient media. According to potential industrial significance of the carotenoids, both their total production and share of individual carotenoids (ß-carotene, γ-carotene, torulene, and torularhodin) were analyzed. The total content of carotenoid pigments in the yeast dry matter ranged from 13.88 to 406.50 µg/g, and the percentages of individual carotenoids highly varied among the strains. Most of the yeast isolates synthesized torulene at the highest amount. Among the studied strains, isolates with a total carotenoid content in biomass greater than 200 µg/g and those containing more than 60% torularhodin were selected for identification (48 strains). The identified strains belonged to six genera: Rhodotorula, Sporidiobolus, Sporobolomyces, Buckleyzyma, Cystofilobasidium, and Erythrobasidium. The largest number of isolates belonged to Rhodotorula babjevae (18), Rhodotorula mucilaginosa (7), Sporidiobolus pararoseus (4), and Rhodotorula glutinis (4).

3.
Foods ; 12(12)2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37372603

RESUMO

The aim of the study was to analyze the influence of mullein flower extract addition on the oxidative stability and antioxidant activity of cold-pressed oils with a high content of unsaturated fatty acids. The conducted research has shown that the addition of mullein flower extract increases the oxidative stability of oils, but its addition depends on the type of oil and should be selected experimentally. In rapeseed and linseed oil, the best stability was found for samples with 60 mg of extract/kg of oil, while in chia seed oil and hemp oil, it was found with 20 and 15 mg of extract/kg of oil, respectively. The hemp oil exhibited the highest antioxidant properties, as evidenced by an increase in the induction time at 90 °C from 12.11 h to 14.05 h. Additionally, the extract demonstrated a protective factor of 1.16. Oils (rapeseed, chia seed, linseed, and hempseed) without and with the addition of mullein extract (2-200 mg of extract/kg of oil) were analyzed for oxidative stability, phenolic compounds content, and antioxidant activity using DPPH• and ABTS•+ radicals. After the addition of the extract, the oils had from 363.25 to 401.24 mg GAE/100 g for rapeseed oil and chia seed oil, respectively. The antioxidant activity of the oils after the addition of the extract ranged from 102.8 to 221.7 and from 324.9 to 888.8 µM Trolox/kg for the DPPH and ABTS methods, respectively. The kinetics parameters were calculated based on the oils' oxidative stability results. The extract increased the activation energy (Ea) and decreased the constant oxidation rate (k).

4.
Foods ; 11(11)2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35681345

RESUMO

The aim of the study was to analyse the chemical composition and oxidation stability of selected cold-pressed oils and oil mixtures. The oils were tested for their initial quality, fatty acid composition, total phenolic compounds, DPPH, and ABTS free radical scavenging activity. The Rancimat method was used to assess oxidative stability. The obtained results were subjected to principal component analysis (PCA) to determine the influence of selected chemical properties on the oxidative stability of the oil. It has been found that different factors of oil quality influence the stability of cold-pressed oils. The highest correlation coefficient was noted between the induction time, peroxide value, and TOTOX indicator (r = 0.89). Fatty acid composition, including the percentage of SFA, MUFA, PUFA, and the ability to scavenge ABTS captions radicals, did not significantly affect the oxidative stability of the oils. Black cumin seed oil was the most resistant to the oxidation processes in the Rancimat apparatus, mainly due to the high content of phenolic compounds (384.66 mg GAE/100 g). On the other hand, linseed oil and its mixtures were the least stable. Their fatty acid composition was dominated by a polyunsaturated α-linolenic fatty acid, significantly reducing the antioxidant resistance.

5.
Molecules ; 26(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34443362

RESUMO

The polyphenol content of tea depends on the growing region, harvest date, the production process used, and the brewing parameters. In this study, research was undertaken that included an analysis of the influence of the brewing process parameters on the content of total polyphenols (Folin-Ciocalteu), epigallocatechin gallate (HPLC), and antioxidant activity (against DPPH radicals) of fresh tea shrub leaves grown from Taiwan and of teas obtained from them (oolong, green in bags, and green loose from the spring and autumn harvest). The antioxidant potential was determined in the methanol and aqueous extracts, as well as in infusions that were obtained by using water at 65 or 100 °C and infusing the tea for 5 or 10 min. The highest content of total polyphenols and epigallocatechin gallate was found in green tea extracts from the spring harvest. However, in the case of infusions, the highest content of these compounds was found in green tea in bags. Steaming at 100 °C for 10 min, turned out to be the most favourable condition for the extraction. Oolong tea, brewed at 100 °C for 5 min was characterised by the highest antioxidant activity against stable DPPH radicals.


Assuntos
Antioxidantes/análise , Camellia sinensis/química , Manipulação de Alimentos/métodos , Folhas de Planta/química , Temperatura , Fatores de Tempo , Água/química
6.
Acta Vet Scand ; 63(1): 24, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112211

RESUMO

BACKGROUND: Captive European bison (Bison bonasus) play an active role in conservation measures for this species; this includes education, which may conflict with these animals' welfare. The effect of the presence of visitors on the welfare of captive animals can be negative, positive or neutral. However, the response of a given species to visitors is difficult to predict, since even closely related species display varying levels of tolerance to captivity. The aim of the study was to compare immunoreactive fecal cortisol levels (regarded as an indicator of the level of physiological stress) in groups of captive European bison that differed in terms of their social structure and the level of visitor pressure. The second aim was to determine if there was a correlation between intestinal parasitic burden and immunoreactive fecal cortisol levels. RESULTS: Immunoreactive fecal cortisol levels were not influenced by sex or age. However, study site and the interaction between study site and visitor pressure were statistically significant. European bison in one enclosure presented higher levels of immunoreactive fecal cortisol on weekdays than at weekends. In the other two study sites, the levels did not differ between weekdays and weekends. No correlation was found between parasitological infestation and immunoreactive fecal cortisol levels. CONCLUSIONS: Measurement of fecal cortisol metabolites could be a valuable method for further research into the welfare of European bison in captivity. More subtle factors such as individual animal characteristics, feeding systems, and the arrangement of enclosures can be of great importance in terms of the effect of visitors on animals. The results of this study can be used in guidelines for the management of European bison populations.


Assuntos
Bison , Bem-Estar do Animal , Animais , Fezes , Hidrocortisona
7.
Acta Sci Pol Technol Aliment ; 20(2): 127-133, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33884851

RESUMO

BACKGROUND: Cold-pressed berry seed oils are used for consumption and other applications including skin and hair care. They are natural products which gain the attention of customers. In this study, strawberry, raspberry and blackberry seed oils used for cosmetic purposes, purchased from three different European producers, were analyzed. The aim of the study was to assess the quality and oxidative stability of the berry fruit oils, thus they were analyzed after purchase and after 4 and 8 weeks of storage at room temperature. METHODS: Acid and peroxide values were determined in the tested oils, as was oxidative stability, which was measured using pressure differential scanning calorimetry (PDSC). Additionally, fatty acid profiles and thei. RESULTS: nd. Cold-pressed berry seed oils are used for consumption and other applications including skin and hair care. They are natural products which gain the attention of customers. In this study, strawberry, raspberry and blackberry seed oils used for cosmetic purposes, purchased from three different European producers, were analyzed. The aim of the study was to assess the quality and oxidative stability of the berry fruit oils, thus they were analyzed after purchase and after 4 and 8 weeks of storage at room temperature. Materials and methods. Acid and peroxide values were determined in the tested oils, as was oxidative stability, which was measured using pressure differential scanning calorimetry (PDSC). Additionally, fatty acid profiles and their distribution at sn-1,3 and sn-2 positions of triacylglycerols were characterized. Results, principal. Most of the fatty acids of the tested berry seed oils are polyunsaturated fatty acids (67.04-74.95%). The results show the low quality of the tested oils in terms of oxidative stability (high peroxide values: 21.9-249.6 mEq O2/kg oil). CONCLUSIONS: Based on this study, it is necessary to evaluate the effects of these products on the body. Moreover, standards clarifying the oxidation of cosmetic oils should be set internationally.


Assuntos
Cosméticos/química , Ácidos Graxos Insaturados/análise , Fragaria/química , Óleos de Plantas/química , Rubus/química , Sementes/química , Ácidos/análise , Temperatura Baixa , Europa (Continente) , Peroxidação de Lipídeos , Oxirredução , Peróxidos/análise , Óleos de Plantas/normas , Triglicerídeos/química
8.
Thyroid ; 18(10): 1125-30, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18844477

RESUMO

Ectopic intrathyroidal thymic tissue is a rare occurrence; parathyroid glands sometimes occur in an intrathyroidal location, but this is uncommon. We report a 6-year-old boy who was noted to have a solitary thyroid nodule on ultrasound. A hemithyroidectomy was performed, and histological investigation revealed that the nodule consisted of ectopic intrathyroidal thymus tissue surrounding a well-defined parathyroidal gland. This condition is an exceedingly rare cause of a thyroid nodule, but intrathyroidal thymic tissue should probably be included in the differential diagnosis of solitary thyroid nodules.


Assuntos
Coristoma/diagnóstico , Glândulas Paratireoides , Timo , Doenças da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/diagnóstico , Criança , Diagnóstico Diferencial , Humanos , Masculino , Doenças da Glândula Tireoide/diagnóstico por imagem , Doenças da Glândula Tireoide/cirurgia , Tireoidectomia , Ultrassonografia
9.
Pediatr Radiol ; 38(5): 543-50, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18299822

RESUMO

BACKGROUND: Ophthalmological complications in patients with mucopolysaccharidosis (MPS) are clouding of the cornea, glaucoma, optic neuropathy, and degeneration of the retina. These changes may impair visual function to the point of total loss of vision. OBJECTIVE: To document the ophthalmological changes demonstrated by grey-scale US in patients with MPS. MATERIALS AND METHODS: A total of 65 patients with MPS (18 type I, 12 type II, 35 type VI) including a subgroup of 30 undergoing enzyme replacement therapy (ERT) were studied by US of the globe and optic nerve. RESULTS: Average scleral thickness at the posterior pole of the globe measured 2.02-2.58 mm (normal range 1.4-1.7 mm), the average diameter of the optic nerve and its sheath measured 5.35-6.71 mm (normal <4.5 mm). All medians were statistically significantly different from those of healthy volunteers. Concomitantly there was hypermetropia of up to 7.5 dioptres. During a mean follow-up of 3.1 years there was no distinct progression in scleral or optic nerve complex thickness. CONCLUSION: The optic nerve sheath and sclera were clearly thickened in comparison to normal values. Many morphological changes in the eye and optic nerve were already present at the time of the initial clinical diagnosis, and thus seem to develop very early in the course of the disease. ERT in our patients did not seem to alter the US characteristics of the globe or optic nerve.


Assuntos
Oftalmopatias/diagnóstico , Oftalmopatias/etiologia , Olho/diagnóstico por imagem , Mucopolissacaridoses/complicações , Adolescente , Adulto , Criança , Pré-Escolar , Seguimentos , Humanos , Pessoa de Meia-Idade , Mucopolissacaridoses/tratamento farmacológico , Mucopolissacaridose I/complicações , Mucopolissacaridose II/complicações , Mucopolissacaridose VI/complicações , Nervo Óptico/diagnóstico por imagem , Papiledema/diagnóstico , Papiledema/etiologia , Esclera/diagnóstico por imagem , Ultrassonografia
10.
Clin Endocrinol (Oxf) ; 64(5): 514-8, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16649969

RESUMO

OBJECTIVE: Congenital primary hypothyroidism occurs in 1 of 4000 births. Whereas the majority of the cases are due to developmental defects of the thyroid gland, 20% carry a defect in thyroid hormonogenesis. We report a Turkish boy who had goitrous hypothyroidism due to a mutation in the thyroid peroxidase (TPO) gene. DESIGN: The TPO gene was sequenced directly from genomic DNA and cDNA which was transcribed from three RNA samples harvested from different parts of the patient's excised thyroid gland. Patient The boy was thyroidectomized because of continuing growth of his thyroid gland and development of multiple nodes suspected of malignancy by ultrasound examination. Histopathological examination verified a dyshormonogenetic goiter with multiple follicular adenomas. RESULTS: The patient had a novel homozygous 10-bp deletion of the TPO gene at position 2812 in exon 16. This frame shift mutation results in a severely altered intracellular part of the protein. The deletion identified in leucocyte DNA was also found in thyroid tissue cDNA - so that instability of the transcript or a splicing defect was excluded. Both unaffected parents were heterozygous carriers of the mutation whereas 50 healthy individuals of the same ethnic background did not harbour the mutation. CONCLUSIONS: The identified TPO gene deletion is the first mutation coding for an inactive TPO molecule, which has a severely altered intracellular segment. Because the most likely reason for the enlarging goiter was poor compliance of the patient, this report underlines the importance of a careful and regular follow-up of patients with dyshormonogenesis.


Assuntos
Adenoma/genética , Hipotireoidismo Congênito/genética , Bócio Nodular/genética , Iodeto Peroxidase/genética , Adenoma/diagnóstico , Adenoma/cirurgia , Adolescente , Hipotireoidismo Congênito/tratamento farmacológico , Hipotireoidismo Congênito/cirurgia , Consanguinidade , Deleção de Genes , Bócio Nodular/diagnóstico , Bócio Nodular/cirurgia , Homozigoto , Humanos , Masculino , Linhagem , Testes de Função Tireóidea , Hormônios Tireóideos/sangue , Tireoidectomia , Tiroxina/sangue , Tiroxina/uso terapêutico , Turquia
11.
Pediatr Nephrol ; 19(3): 357-60, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14685844

RESUMO

Perirenal extravasation of urine is a rare event in congenital uropathies, mostly observed perinatally in the case of infravesical obstruction. We describe a male infant with a primary non-refluxing obstructive left megaureter who developed an acute perirenal extravasation and ascites at the age of 4 weeks. After temporary upper urinary diversion, ureterocystoneostomy was successfully performed. Intraoperatively, the distal ureter showed an extremely narrow lumen over a distance of 3 cm. In the current literature, postnatal management of primary megaureters is preferably conservative. Our patient demonstrates an extremely rare complication demanding early surgical intervention.


Assuntos
Ascite/etiologia , Ureter/anormalidades , Obstrução Ureteral/complicações , Obstrução Ureteral/diagnóstico por imagem , Doença Aguda , Ascite/diagnóstico por imagem , Humanos , Recém-Nascido , Masculino , Ultrassonografia , Ureter/diagnóstico por imagem , Obstrução Ureteral/cirurgia , Urina
12.
Pediatr Radiol ; 32(12): 839-43, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12447586

RESUMO

BACKGROUND: It has been suggested that tungsten coils (TCs) may corrode 30 months after transcatheter embolisation (TCE). The aim of this study was to follow up children after TCE of aorto-pulmonary collaterals (APCs) with TCs. MATERIALS AND METHODS: Successful TCE of 99 APCs was performed in children using 152 TCs. Chest radiographs were obtained on the day after the procedure, after 3-6 months and 9-12 months, and yearly thereafter. RESULTS: Mean follow-up was 39.3 months. After 9-12 months, radiographs revealed a decrease in radio-opacity and reduction of coil width in 29 (37.6%) of 77 APCs. After a mean of 25 months (range 13-51 months), there was loss of visibility in 44 (57.2%) of 77 TCs and a reduction in 29 (37.6%) of 77. After a mean of 39.3 months, all TCs showed decrease or loss of radio-opacity. Exponential function predicts complete biodegradation of 95% of TCs within 10 years after TCE (r2= 0.923). After a mean of 28.4 months, repeat catheterisation was performed in 24 APCs with TCs with decreased or lost radio-opacity. Recanalisation had occurred in 58.3%. CONCLUSIONS: Dissolution occurred in 57.2% of TCs within a mean of 25 months, and within 39.3 months all TCs showed decrease or loss of radio-opacity. Recanalisation of closed APCs occurred in 58.3%.


Assuntos
Embolização Terapêutica/instrumentação , Compostos de Tungstênio/química , Biodegradação Ambiental , Criança , Pré-Escolar , Circulação Colateral , Falha de Equipamento , Seguimentos , Humanos , Lactente , Recém-Nascido , Radiografia Torácica , Análise de Regressão
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...