Mild oxidative cleavage of β,β-carotene by dioxygen induced by a ruthenium porphyrin catalyst: characterization of products and of some possible intermediates

2001 ◽  
Vol 25 (2) ◽  
pp. 203-206 ◽  
Author(s):  
Catherine Caris-Veyrat ◽  
Marie-Josèphe Amiot ◽  
Rene´ Ramasseul ◽  
Jean-Claude Marchon
Keyword(s):  
Oxidative Cleavage ◽  
Catalyst Characterization ◽  
Ruthenium Porphyrin ◽  
Β Carotene

Quantitative nano-characterization of heterogeneous catalysts

1995 ◽  
Vol 53 ◽  
pp. 398-399
Author(s):  
P.A. Crozier ◽  
M. Pan
Keyword(s):  
Heterogeneous Catalysts ◽  
Low Dose ◽  
Imaging Techniques ◽  
Structural Features ◽  
Catalyst Characterization ◽  
New Developments ◽  
Double Phase ◽  
Phase Systems ◽  
Dose Imaging

Heterogeneous catalysts can be of varying complexity ranging from single or double phase systems to complicated mixtures of metals and oxides with additives to help promote chemical reactions, extend the life of the catalysts, prevent poisoning etc. Although catalysis occurs on the surface of most systems, detailed descriptions of the microstructure and chemistry of catalysts can be helpful for developing an understanding of the mechanism by which a catalyst facilitates a reaction. Recent years have seen continued development and improvement of various TEM, STEM and AEM techniques for yielding information on the structure and chemistry of catalysts on the nanometer scale. Here we review some quantitative approaches to catalyst characterization that have resulted from new developments in instrumentation.HREM has been used to examine structural features of catalysts often by employing profile imaging techniques to study atomic details on the surface. Digital recording techniques employing slow-scan CCD cameras have facilitated the use of low-dose imaging in zeolite structure analysis and electron crystallography. Fig. la shows a low-dose image from SSZ-33 zeolite revealing the presence of a stacking fault.

scholarly journals Modulation of Gut Microbiota and Oxidative Status by β-Carotene in Late Pregnant Sows

2020 ◽  
Vol 7 ◽  
Author(s):  
Xupeng Yuan ◽  
Jiahao Yan ◽  
Ruizhi Hu ◽  
Yanli Li ◽  
Ying Wang ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Dietary Supplementation ◽  
Basal Diet ◽  
Fecal Microbiota ◽  
Control Group ◽  
Metabolic Activities ◽  
The Impact ◽  
Positive Effect ◽  
Β Carotene

Recent evidences suggest that gut microbiota plays an important role in regulating physiological and metabolic activities of pregnant sows, and β-carotene has a potentially positive effect on reproduction, but the impact of β-carotene on gut microbiota in pregnant sows remains unknown. This study aimed to explore the effect and mechanisms of β-carotene on the reproductive performance of sows from the aspect of gut microbiota. A total of 48 hybrid pregnant sows (Landrace × Yorkshire) with similar parity were randomly allocated into three groups (n = 16) and fed with a basal diet or a diet containing 30 or 90 mg/kg of β-carotene from day 90 of gestation until parturition. Dietary supplementation of 30 or 90 mg/kg β-carotene increased the number of live birth to 11.82 ± 1.54 and 12.29 ± 2.09, respectively, while the control group was 11.00 ± 1.41 (P = 0.201). Moreover, β-carotene increased significantly the serum nitric oxide (NO) level and glutathione peroxidase (GSH-Px) activity (P < 0.05). Characterization of fecal microbiota revealed that 90 mg/kg β-carotene increased the diversity of the gut flora (P < 0.05). In particular, β-carotene decreased the relative abundance of Firmicutes including Lachnospiraceae AC2044 group, Lachnospiraceae NK4B4 group and Ruminococcaceae UCG-008, but enriched Proteobacteria including Bilophila and Sutterella, and Actinobacteria including Corynebacterium and Corynebacterium 1 which are related to NO synthesis. These data demonstrated that dietary supplementation of β-carotene may increase antioxidant enzyme activity and NO, an important vasodilator to promote the neonatal blood circulation, through regulating gut microbiota in sows.

THE CHARGE TRANSFER COMPLEX BETWEEN β-CAROTENE AND IODINE. II. CHARACTERIZATION OF COMPLEX1

1963 ◽  
Vol 67 (12) ◽  
pp. 2725-2728 ◽  
Author(s):  
J. H. Lupinski
Keyword(s):  
Charge Transfer ◽  
Charge Transfer Complex ◽  
Β Carotene

Isolation and characterization of cDNAs encoding β-carotene hydroxylase in Citrus

Plant Science ◽  
2001 ◽  
Vol 161 (5) ◽  
pp. 1005-1010 ◽  
Author(s):  
In-Jung Kim ◽  
Kyong-Cheol Ko ◽  
Chan-Shick Kim ◽  
Won-Il Chung
Keyword(s):  
Isolation And Characterization ◽  
Β Carotene

scholarly journals Characterization of Striga-Resistant Yellow-Orange Maize Hybrids for Bioactive, Carbohydrate, and Pasting Properties

2020 ◽  
Vol 4 ◽  
Author(s):  
Abdulazeez Olamilekan Elemosho ◽  
Emmanuel Anyachukwu Irondi ◽  
Emmanuel Oladeji Alamu ◽  
Emmanuel Oladipipo Ajani ◽  
Busie Maziya-Dixon ◽  
...  
Keyword(s):  
Pasting Properties ◽  
Free Sugar ◽  
Bioactive Constituents ◽  
Potential Health ◽  
Maize Hybrids ◽  
Yellow Orange ◽  
Food Applications ◽  
Pasting Temperature ◽  
Β Carotene

Understanding the bioactive constituents and physicochemical components in cereals can provide insights into their potential health benefits and food applications. This study evaluated some bioactive constituents, carbohydrate profiles and pasting properties of 16 Striga-resistant hybrids, with yellow-orange kernel color and semi-flint to flint kernel texture, grown in two replications at two field locations in Nigeria. Carotenoids were quantified using HPLC, while other analyses were carried out using standard laboratory methods. The ranges of major carotenoids (μg/g) across the two locations varied from 2.6 to 9.6 for lutein, from 2.1 to 9.7 for zeaxanthin, from 0.8 to 2.9 for β-cryptoxanthin, from 1.4 to 4.1 for β-carotene; with total xanthophylls and provitamin A carotenoids (pVAC) ranging from 5.4 to 17.1 and 1.4 to 4.1 μg/g, respectively. Tannins content ranged from 2.1 to 7.3 mg/g, while phytate ranged from 0.4 to 7.1%. Starch, free sugar, amylose and amylopectin ranged from 40.1 to 88.9%, 1.09 to 6.5%, 15.0 to 34.1%, and 65.9 to 85.0%, respectively. Peak and final viscosities ranged from 57.8 to 114.9 and 120.3 to 261.6 Rapid Visco Units (RVU), respectively. Total xanthophylls, β-carotene, tannins, phytate, sugar, amylose and amylopectin levels, as well as peak and final viscosities, varied significantly (p < 0.05) across the hybrids. Amylose was significantly correlated (p < 0.05) with total xanthophylls, β-carotene, pVAC, phytate and pasting temperature (r = 0.3, 0.3, 0.4, 0.3, 0.3, respectively), but starch significantly correlated with tannins (r = 0.3). Hence, the Striga-resistant yellow-orange maize hybrids have a good combination of bioactive constituents, carbohydrate profile and pasting properties, which are partly influenced by hybrid.

scholarly journals Characterization of crtRB1 Gene Polymorphism and β-Carotene Content in Maize Landraces Originated From North Eastern Himalayan Region (NEHR) of India

2020 ◽  
Vol 4 ◽  
Author(s):  
Senthil Natesan ◽  
Thangjam Surchandra Singh ◽  
Thirusenduraselvi Duraisamy ◽  
Neelima Chandrasekharan ◽  
Sarankumar Chandran ◽  
...  
Keyword(s):  
Gene Polymorphism ◽  
Himalayan Region ◽  
Carotene Content ◽  
North Eastern ◽  
Maize Landraces ◽  
Eastern Himalayan Region ◽  
Β Carotene

scholarly journals Biflavonoids from the Unripe Fruits of Clusia Paralicola and their Antioxidant Activity

2012 ◽  
Vol 7 (12) ◽  
pp. 1934578X1200701 ◽  
Author(s):  
Rafaela Ferreira Oliveira ◽  
Celso Amorim Camara ◽  
Maria de Fátima Agra ◽  
Tania Maria Sarmento Silva
Keyword(s):  
Antioxidant Activity ◽  
Linoleic Acid ◽  
Spectral Data ◽  
2D Nmr ◽  
Cd Spectra ◽  
Total Extract ◽  
Isolation And Characterization ◽  
Β Carotene ◽  
Unripe Fruits

Investigation of the green fruits of Clusia paralicola (Clusiaceae) led to the isolation and characterization of two 3,8″-biflavonoids, 2R, 3S, 2″R, 3″R-GB1-7″- O-β-glucoside (1) and 2R, 3S, 2″R, 3,8″-binaringenin-7″-O-β-glucoside (2), together with four known compounds: β-sitosterol, stigmasterol, β-amyrin, and epicatechin. The structures were established from the IR, LC-ESI-MS and NMR spectral data, including 2D-NMR experiments. The absolute configurations of 1 and 2 were determined by CD spectra. The total extract and the biflavonoids demonstrated significant antioxidant activity in DPPH, ABTS, and β-carotene/linoleic acid tests.

ChemInform Abstract: SEPARATION AND CHARACTERIZATION OF β-CAROTENE ISOMERS

1982 ◽  
Vol 13 (14) ◽  
Author(s):  
M. VECCHI ◽  
G. ENGLERT ◽  
R. MAURER ◽  
V. MEDUNA
Keyword(s):  
Β Carotene
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