Background: α-Tocopherol can exist as eight possible stereoisomers due to the presence of three chiral carbons. Regulations and industry guidelines necessitate that dietary vitamin E intakes be based on the vitamin E activity of RRR-α-tocopherol. Food products fortified with synthetic all-rac-α-tocopherol or all-rac-α-tocopheryl acetate during manufacturing will require chiral separation of the α-tocopherol stereoisomers for accurate estimation of vitamin E activity.
Objective: The development of an HPLC method utilizing a chiral column for the chromatographic separation of RRR-α-tocopherol from other α-tocopherol stereoisomers.
Method: Normal phase liquid chromatographic separation using a polysaccharide-based chiral column with fluorescence detection of α-tocopherol stereoisomers.
Results: The described chromatographic method achieves baseline resolution of RRR-α-tocopherol from its stereoisomers. Method selectivity, precision, and robustness were evaluated and acceptable performance was achieved.
Conclusions: The chromatographic method was found to be suitable for application where both RRR-α-tocopherol content and total α-tocopherol content are required for routine compliance testing.
Highlights: A robust and precise chomatographic method for the baseline resolution of RRR-α-tocopherol from its stereoisomers was acheived.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1093/jaoacint/qsaa055 | DOI Listing |
Sleep Breath
January 2025
Department of Pulmonary and Critical Care Medicine, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, No.1 Da Hua Road, Dong Dan, Dongcheng District, Beijing, 100730, PR China.
Purpose: To investigate the relationship between obstructive sleep apnea hypopnea syndrome (OSAHS) severity and fat, bone, and muscle indices.
Methods: This study included 102 patients with OSAHS and retrospectively reviewed their physical examination data. All patients underwent polysomnography, body composition analysis, dual-energy X-ray absorptiometry, computed tomography (CT) and blood test.
J Youth Adolesc
January 2025
Manchester Institute of Education, University of Manchester, Manchester, UK.
Current understanding of the longitudinal relationships between different aspects of peer relationships and mental health problems in early- to mid-adolescence is limited. In particular, the role played by gender in these developmental cascades processes is unclear, little is known about within-person effects between bullying victimization and internalizing symptoms, and the theorized benefits of friendship and social support are largely untested. Addressing these important research gaps, this study tested a number of theory-driven hypotheses (e.
View Article and Find Full Text PDFJ Mol Histol
January 2025
Department of Histology and Embryology, Faculty of Medicine, Trakya University, Edirne, 22030, Turkey.
Genital tract infections are common causes of male infertility, and most of diagnosed men are asymptomatic. This study examined the effect of gallic acid (GA) against lipopolysaccharide (LPS)-induced testicular inflammation. Thirty-two Spraque Dawley, 2.
View Article and Find Full Text PDFLangmuir
January 2025
School of Textile Science and Engineering, Tiangong University, Tianjin 300387, China.
Aerogels hold great potential in thermal insulation, catalytic supports, adsorption, and separation, due to their low density, high porosity, and low thermal conductivity. However, their inherent mechanical fragility and limited control functionality pose substantial challenges that hinder their practical use. In this study, a strategy is developed for the fabrication of cross-linked aramid nanofiber aerogels (cANFAs) by combining internanofiber surface cross-linking with ice-templating techniques.
View Article and Find Full Text PDFPsychol Health Med
January 2025
Gebze Fatih Public Hospital, Cardiovascular Surgery Intensive Care Unit, Gebze, Turkey.
Analyzing the levels of forgiveness and compassion, which may influence patient care and professional attitudes of the nurses, may provide data for nursing education and practices. The purpose of this study was to evaluate the relationship between compassion, forgiveness, and the caring behaviors of the nurses and reveal the role of compassion on forgiveness and nursing care behaviors. This cross-sectional study was conducted at a research and training hospital between July and December 2021 with 515 nurses.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!