The Structural and Biochemical Basis of Apocarotenoid Processing by β-Carotene Oxygenase-2

2021 ◽  
Author(s):  
Sepalika Bandara ◽  
Linda D. Thomas ◽  
Srinivasagan Ramkumar ◽  
Nimesh Khadka ◽  
Philip D. Kiser ◽  
...  
Keyword(s):  
Biochemical Basis ◽  
Β Carotene

Serum Retinol and β-carotene Levels and Risk Factors for Cardiovascular Disease in Morbid Obesity

2010 ◽  
Vol 80 (3) ◽  
pp. 159-167 ◽  
Author(s):  
Gabriela Villaça Chaves ◽  
Gisele Gonçalves de Souza ◽  
Andréa Cardoso de Matos ◽  
Dra. Wilza Abrantes Peres ◽  
Silvia Elaine Pereira ◽  
...  
Keyword(s):  
Risk Factors ◽  
Cardiovascular Disease ◽  
Metabolic Syndrome ◽  
Morbid Obesity ◽  
Serum Levels ◽  
World Health ◽  
Morbidly Obese ◽  
Serum Retinol ◽  
Significant Difference ◽  
Β Carotene

Objective: To evaluate retinol and β-carotene serum levels and their relationship with risk factors for cardiovascular disease in individuals with morbid obesity, resident in Rio de Janeiro. Methodology: Blood serum concentrations of retinol and β-carotene of 189 morbidly obese individuals were assessed. The metabolic syndrome was identified according to the criteria of the National Cholesterol Education Program (NCEP) and World Health Organization (WHO). Lipid profile, insulin resistance, basal insulin, glycemia, blood pressure, and anthropometry and their correlation with retinol and β-carotene serum levels were evaluated. Results: Metabolic syndrome diagnosis was observed in 49.0% of the sample. Within this percentage the levels of β-carotene were significantly lower when body mass index increased. Serum retinol didn't show this behavior. Serum retinol inadequacy in patients with metabolic syndrome (61.3%), according to WHO criterion, was higher (15.8%) than when the whole sample was considered (12.7%). When metabolic syndrome was diagnosed by NCEP criterion, β-carotene inadequacy was higher (42.8%) when compared to the total sample (37.5%). There was a significant difference between average β-carotene values of patients with and without metabolic syndrome (p=0.048) according to the classification of the NCEP. Lower values were found in patients with metabolic syndrome. Conclusion: Considering the vitamin A contribution in antioxidant protection, especially when risk factors for cardiovascular disease are present, it is suggested that great attention be given to morbidly obese. This could aid in prevention and treatment of cardiovascular disease, which affects a significant part of the population.

Vitamin A Value of Plant Food Provitamin A - Evaluated by the Stable Isotope Technologies

2014 ◽  
Vol 84 (Supplement 1) ◽  
pp. 25-29 ◽  
Author(s):  
Guangwen Tang
Keyword(s):  
Stable Isotope ◽  
Vitamin A ◽  
Provitamin A ◽  
Animal Origin ◽  
Plant Food ◽  
Plant Foods ◽  
A Value ◽  
Provitamin A Carotenoids ◽  
Β Carotene

Humans need vitamin A and obtain essential vitamin A by conversion of plant foods rich in provitamin A and/or absorption of preformed vitamin A from foods of animal origin. The determination of the vitamin A value of plant foods rich in provitamin A is important but has challenges. The aim of this paper is to review the progress over last 80 years following the discovery on the conversion of β-carotene to vitamin A and the various techniques including stable isotope technologies that have been developed to determine vitamin A values of plant provitamin A (mainly β-carotene). These include applications from using radioactive β-carotene and vitamin A, depletion-repletion with vitamin A and β-carotene, and measuring postprandial chylomicron fractions after feeding a β-carotene rich diet, to using stable isotopes as tracers to follow the absorption and conversion of plant food provitamin A carotenoids (mainly β-carotene) in humans. These approaches have greatly promoted our understanding of the absorption and conversion of β-carotene to vitamin A. Stable isotope labeled plant foods are useful for determining the overall bioavailability of provitamin A carotenoids from specific foods. Locally obtained plant foods can provide vitamin A and prevent deficiency of vitamin A, a remaining worldwide concern.

Enhancement of Plasminogen Binding to U937 Cells and Fibrin by Complestatin

1997 ◽  
Vol 77 (01) ◽  
pp. 137-142 ◽  
Author(s):  
Kiyoshi Tachikawa ◽  
Keiji Hasurni ◽  
Akira Endo
Keyword(s):  
Binding Site ◽  
Binding Affinity ◽  
Blood Cells ◽  
Aminocaproic Acid ◽  
U937 Cells ◽  
Biochemical Basis ◽  
Equilibrium Binding ◽  
Pharmacological Stimulation ◽  
Endogenous Fibrinolysis ◽  
Stimulation Of

SummaryPlasminogen binds to endothelial and blood cells as well as to fibrin, where the zymogen is efficiently activated and protected from inhibition by α2-antiplasmin. In the present study we have found that complestatin, a peptide-like metabolite of a streptomyces, enhances binding of plasminogen to cells and fibrin. Complestatin, at concentrations ranging from 1 to 5 μM, doubled 125I-plasminogen binding to U937 cells both in the absence and presence of lipoprotein(a), a putative physiological competitor of plasminogen. The binding of 125I-plasminogen in the presence of complestatin was abolished by e-aminocaproic acid, suggesting that the lysine binding site(s) of the plasminogen molecule are involved in the binding. Equilibrium binding analyses indicated that complestatin increased the maximum binding of 125I-plasminogen to U937 cells without affecting the binding affinity. Complestatin was also effective in increasing 125I-plasminogen binding to fibrin, causing 2-fold elevation of the binding at ~1 μM. Along with the potentiation of plasminogen binding, complestatin enhanced plasmin formation, and thereby increased fibrinolysis. These results would provide a biochemical basis for a pharmacological stimulation of endogenous fibrinolysis through a promotion of plasminogen binding to cells and fibrin.

Biochemical basis of selective disease controlling activity of mepanipyrim

2007 ◽  
Vol 32 (2) ◽  
pp. 77-82 ◽  
Author(s):  
Ichiro Miura ◽  
Shinichiro Maeno
Keyword(s):  
Biochemical Basis

Évaluation de la teneur des composés phénoliques, des proprieties antioxydantes et antimicrobiennes de l’espèce Erica arborea L. (Ericaceae) dans la médecine traditionnelle du Tell sétifien dans l’Est Algérien

2019 ◽  
Author(s):  
K. Yaici ◽  
S. Dahamna ◽  
I. Moualek ◽  
H. Belhadj ◽  
K. Houali
Keyword(s):  
Activité Antioxydante ◽  
Activité Antimicrobienne ◽  
Médecine Traditionnelle ◽  
Composés Phénoliques ◽  
Bacillus Subtilus ◽  
Erica Arborea ◽  
Infections Urinaires ◽  
Flavonoïdes Totaux ◽  
Extraits Aqueux ◽  
Β Carotene

Les sommités florales d’Erica arboea L. sont largement utilisées sous forme d’infusion en médecine traditionnelle et sont recommandées dans le Tell sétifien pour traiter et prévenir les infections urinaires aiguës et chroniques principalement. Nous avons soumis les extraits aqueux des feuilles et des fleurs à un dosage des polyphénols, des flavonoïdes et à la détermination des activités antioxydante et antimicrobienne. Les teneurs en composés phénoliques et flavonoïdes totaux ont montré une corrélation avec les activités antioxydantes évaluées. Les tests antioxydants utilisés (DPPH, FRAP, CAT, blanchiment du β-carotène et piégeage du radical hydroxyle) ont montré que le test du DPPH a donné la meilleure activité radicalaire. En outre, l’extrait des feuilles s’est mieux exprimé dans les tests du DPPH, du FRAP et du β- carotène. Les tests de la CAT et le radical hydroxyle ont par contre révélé une activité antioxydante plus importante pour l’extrait de fleurs. Pour l’activité antimicrobienne, on a utilisé la méthode de diffusion en milieu gélosé en ayant recours à la méthode des puits. Les deux extraits ont montré une activité antimicrobienne contre les bactéries à Gram positif Staphylococcus aureus ATCC25923, Bacillus subtilus CLAM20302, Bacillus cereus CLAMH300. L’extrait des feuilles a été plus actif avec une valeur variant de 15 à 23 mm comparé à celui des fleurs (17–18,5 mm). Les valeurs de la concentration minimale inhibitrice ont été trouvées dans une gamme variant de 6,25 à 25 mg/ml pour les extraits des feuilles et des fleurs respectivement. Les résultats de l’étude peuvent enrichir les données existantes et montrent que les feuilles et les fleurs d’Erica arborea L. constituent une source d’agents antioxydants et antibactériens.

LYCOPENE POWDER PRODUCING FROM GAC FRUIT TOWARDS APPLICATIONS IN NUTRACEUTICAL AND COSMETICS

2016 ◽  
pp. 51-56
Author(s):  
Thi Le Thuy Nguyen ◽  
Thanh Sinh Do ◽  
Thi Hoa Tran
Keyword(s):  
Key Words ◽  
Propylene Glycol ◽  
Mass Production ◽  
Toxic Substances ◽  
High Concentration ◽  
Concentration Determination ◽  
Modified Method ◽  
Β Carotene ◽  
Key Words Carotenoids

Backgroud: Gac is a fruit containing many antioxidants, especially lycopene, with high concentration. However the variety and value of products from gac are limited. We introduce a modified method to produce lycopene and others carotenoids from gac oil towards available and safe applications in nutraceutical and cosmetics. Materials and method: We study the extraction with different parameters and limit at the saponification of gac oil using less toxic substances such as ethanol, propylene glycol, postasium hydroxide and sodium chlorid. Results: Concentrations of lycopene and β-carotene determined silmutaneously by UVVis spectrophotometer present that the efficiency reaches 65.07% as 20 g of gac oil is saponified with 8 g KOH 12 mol/L in 120 mins. The purity of product is 89.02%. Conclusions: This process could minimize toxic residue in the powder after the precipitation, filtration and washing. Besides, the method is stable and applicable to the mass production. Key words: Carotenoids, Lycopene, safe extraction, UV Vis silmutaneous concentration determination

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