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1.
Molecules ; 27(4)2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35209139

RESUMO

Extra virgin olive oil (EVOO) is a key component of the Mediterranean diet, with several health benefits derived from its consumption. Moreover, due to its eminent market position, EVOO has been thoroughly studied over the last several years, aiming at its authentication, but also to reveal the chemical profile inherent to its beneficial properties. In the present work, a comparative study was conducted to assess Greek EVOOs' quality and authentication utilizing different analytical approaches, both targeted and untargeted. 173 monovarietal EVOOs from three emblematic Greek cultivars (Koroneiki, Kolovi and Adramytiani), obtained during the harvesting years of 2018-2020, were analyzed and quantified as per their fatty acids methyl esters (FAMEs) composition via the official method (EEC) No 2568/91, as well as their bioactive content through liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS) methodology. In addition to FAMEs analysis, EVOO samples were also analyzed via HRMS-untargeted metabolomics and optical spectroscopy techniques (visible absorption, fluorescence and Raman). The data retrieved from all applied techniques were analyzed with Machine Learning methods for the authentication of the EVOOs' variety. The models' predictive performance was calculated through test samples, while for further evaluation 30 commercially available EVOO samples were also examined in terms of variety. To the best of our knowledge, this is the first study where different techniques from the fields of standard analysis, spectrometry and optical spectroscopy are applied to the same EVOO samples, providing strong insight into EVOOs chemical profile and a comparative evaluation through the different platforms.


Assuntos
Análise de Alimentos , Qualidade dos Alimentos , Azeite de Oliva/química , Azeite de Oliva/normas , Ácidos Graxos/análise , Análise de Alimentos/métodos , Ingredientes de Alimentos/análise , Grécia , Metabolômica/métodos , Análise Espectral
2.
Molecules ; 25(17)2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32839421

RESUMO

Extra virgin olive oil (EVOO) is an important component of the Mediterranean diet and a highly priced product. Despite the strict legislation to protect it from fraudulent practices, there is an increasing demand to characterize EVOOs and evaluate their authenticity. For this purpose, 68 monovarietal EVOOs, originating from three regions of Greece (Peloponnese, Crete, and Lesvos) and two local cultivars (Koroneiki and Kolovi), were obtained during the harvesting period of 2018-2019. Fatty acids, squalene, and tocopherols were determined chromatographically according to official methods in order to study the effect of cultivar and geographical origin. Squalene and γ-tocopherol differed significantly amongst the cultivars tested. Koroneiki samples exhibited higher squalene content than Kolovi samples, whereas the opposite was observed for γ-tocopherol. The tocopherol level was highly geographical dependent, with EVOOs from Peloponnese displaying the highest concentration of α-tocopherol, whereas the content of γ-tocopherol was significantly higher in samples from Lesvos. Unsupervised and supervised multivariate analysis resulted in a satisfactory grouping of EVOOs according to cultivar. γ-Tocopherol, squalene, and the majority of fatty acids were the most discriminant variables, with γ-tocopherol, linoleic, linolenic, and gadoleic acid being present at higher levels in samples from the Kolovi cultivar. Koroneiki samples were characterized with higher levels of squalene, palmitic, palmitoleic, and arachidic acid.


Assuntos
Ácidos Graxos/análise , Análise de Alimentos , Azeite de Oliva/análise , Esqualeno/análise , Tocoferóis/análise
3.
Beilstein J Org Chem ; 14: 838-848, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29719578

RESUMO

The role of beta-cyclodextrin (ß-CD) in cholesterol removal primarily from mammalian cells and secondly from dairy products has been studied thoroughly in recent years. Although the physicochemical characterization of the inclusion compound of cholesterol in ß-CD has been achieved by various methods, no crystal structure has been determined so far. We report here the crystal structure of the inclusion compound of cholesterol in ß-CD. The inclusion complex crystallizes in the triclinic space group P1 forming head-to-head dimers which are stacked along the c-axis. One well-defined cholesterol molecule 'axially' encapsulated inside the ß-CD dimer and 22 water molecules that stabilize the complexes in the crystalline state comprise the asymmetric unit of the structure. The dimers are arranged in an intermediate (IM) channel packing mode in the crystal. Moreover, MD simulations, at 300 and 340 K, based on the crystallographically determined coordinates of the complex show that the formed cholesterol/ß-CD inclusion compound remains very stable in aqueous solution at both temperatures.

4.
Am J Clin Nutr ; 118(5): 1010-1019, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37640108

RESUMO

BACKGROUND: In Greece, nearly a third of savory baked goods (SBGs) exceeded the limit of 2 g of nonruminant or industrial trans fatty acids (i-TFA) per 100 g fat in 2015. The impact of the Commission Regulation (European Union) 2019/649 on exposure to trans fatty acids (TFA), i-TFA, and saturated fatty acid (SFA) from SBGs has not been previously evaluated. OBJECTIVES: The study aimed to explore fatty acid reformulation of SBG products and assess differences in TFA, i-TFA, and SFA intakes using a sample of Greek SBG consumers from a nationally representative survey. METHODS: In 2021, 140 samples of SBGs were collected in the greater metropolitan area of Athens, and their fat profile and content were compared to those from 2015. Based on these measurements, food consumption substitution models were employed to examine TFA and SFA intake differences, and the percent contribution from SBG among consumers was calculated (N = 1008). Nutrient densities were calculated by adjusting all fat intakes by individual mean energy intake (percentage of daily total energy intake). RESULTS: The 2% i-TFA legislative limit/100 g of fat in measured SBGs was exceeded by 11.4% in 2021 compared to 31.1% in 2015 (19.7% increase in compliance). Median i-TFA and TFA intakes from SBGs were reduced from 0.05 (0.01, 0.12)% and 0.13 (0.03, 0.27)% in 2015 to 0.03 (0.01, 0.09) and 0.06 (0.03, 0.13)% in 2021, respectively. In terms of SFA, a mean increase/100 g was calculated, resulting in an increased intake in 2021 compared to 2015 [5.18% (2.78, 8.37) and 3.55 (1.99, 5.73), respectively]. CONCLUSIONS: Despite the reductions seen in i-TFA content of SBGs, food product reformulation efforts in Greece should focus not only on TFA content but also on SFA reduction to improve public health.


Assuntos
Ácidos Graxos , Ácidos Graxos trans , Humanos , Grécia , Gorduras na Dieta , Ingestão de Energia
5.
Biomolecules ; 12(12)2022 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-36551190

RESUMO

Piperine (PN), the primary pungent alkaloid in black pepper shows several biological activities such as antioxidant, antimicrobial and anti-cancerogenic effects. Similar to other alkaloids, PN is characterized by poor water solubility. One way to improve its solubility and thus its biological activities is by forming inclusion complexes with suitable cyclodextrins. In this work PN inclusion complexes in native ß-cyclodextrin (ß-CD), its methylated (randomly methylated (RM-ß-CD), heptakis-(2,6-di-O-methyl)-ß-CD (DM-ß-CD) and heptakis-(2,3,6-tri-O-methyl)-ß-CD (TM-ß-CD)) and 2-hydroxypropylated (HP-ß-CD) derivatives are investigated using physicochemical methods, such as phase solubility study and X-ray crystallography complemented by theoretical (molecular dynamics simulations) studies. The determination of the crystal structure of the PN inclusion complexes in ß-CD, DM-ß-CD and TM-ß-CD, reveals the formation of 1:2 guest:host inclusion complexes in the crystalline state. The guest PN molecule threads the hydrophobic cavities of the hosts which are arranged as couples in a tail-to-tail mode in the case of PN/ß-CD and in a head-to-tail mode in the cases of PN/DM-ß-CD and PN/TM-ß-CD. MD studies based on the crystallographically determined structures and docked models show the stability of the examined complexes in an aqueous environment whereas the binding affinity of PN for the host molecules is calculated by the MM/GBSA method. Finally, phase-solubility studies of PN with ß-CD, RM-ß-CD and HP-ß-CD are presented, indicating a Bs-type for the PN/ß-CD complex and an AL-type for the PN/RM-ß-CD and PN/HP-ß-CD complexes with 1:1 guest:host stoichiometry.


Assuntos
Alcaloides , Ciclodextrinas , beta-Ciclodextrinas , 2-Hidroxipropil-beta-Ciclodextrina , beta-Ciclodextrinas/química , Ciclodextrinas/química , Solubilidade
6.
Clin Chem Lab Med ; 45(11): 1488-94, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17924845

RESUMO

BACKGROUND: The clinical relevance of positive molecular staging as defined by reverse transcriptase-polymerase chain reaction (RT-PCR) detections of both prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA) transcripts in the peripheral blood (PB) of patients with prostate cancer is still debatable. METHODS: We analyzed the biochemical failure-free survival (bFFS) of prostate cancer patients with positive molecular staging who underwent immediate curative therapy (Group I, n=39) compared to prostate cancer patients who did convert their positive molecular staging by the administration of combined androgen blockade (CAB) for 12 months prior to curative treatment (Group II, n=15). RESULTS: The median bFFS for Group I was 9 months (95% CI 5-13 months) and was significantly lower compared to Group II (>36 months, p<0.001). In Group I, the median time for PSA values of >2.0 ng/mL was 18 months (95% CI 12-21 months, range 12-36 months). Notably, only one patient from Group II reached PSA values>2.0 ng/mL at 36 months post-curative treatment. CONCLUSIONS: In patients with clinically localized prostate cancer and positive RT-PCR detection of PSA and PSMA transcripts in PB, CAB can convert positive molecular staging status to negative and by doing so it modifies the post-curative therapy bFFS of patients with clinically localized prostate cancer.


Assuntos
Antagonistas de Androgênios/farmacologia , Antígeno Prostático Específico/genética , Neoplasias da Próstata/sangue , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Idoso , Antígenos de Superfície , Intervalo Livre de Doença , Glutamato Carboxipeptidase II , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Neoplasias da Próstata/terapia , RNA Mensageiro/sangue
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