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Mar 2019 DOI 10.14302/issn.2379-7835.ijn-19-2677
Grootveld MartinCorresponding author
Leicester School of Pharmacy, De Montfort University, The Gateway, Leicester LE1 9BH, United Kingdom
Objectives: Sunflower oil (SFO) is regularly employed for cosmetic, emollient and food frying purposes, the latter representing its foremost use globally. Therefore, full investigations of the molecular composition and quality of SFO products are a major requirement. In this study high-field 1H NMR analysis was employed to explore the molecular composition and authenticities of East African virgin (EAV) SFO products, particularly their acylglycerol fatty acid contents, together with those of selected minor constituents. Results acquired were statistically compared to those obtained on commercially-available, EU-approved refined SFO products via NMR-linked multivariate chemometrics strategies. Methodology: High-field 1H NMR spectra of EAV and refined SFOs (n = 55 and 4 respectively) were acquired at an operating frequency of 400 MHz. Their triacylglycerol fatty acid, triacylglycerol hydrolysis product, and sterol and stanol contents were determined via intelligent frequency bucketing and electronic integration of selected resonances. Univariate analysis-of-variance, and multivariate ROC curve evaluations were conducted to determine the magnitude and statistical significance of analyte concentration differences between these two sample classifications. Further multivariate NMR-linked chemometrics analyses such as principal component, random forest and support vector machine classification analyses were also utilised for this purpose. Key Results: Multicomponent 1H NMR analysis demonstrated that EAV SFOs had significantly higher and lower contents of monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs), respectively, than those of refined SFOs. Furthermore, significantly higher concentrations of ‘health-friendly’, cholesterol-blocking sterols and stanols were also found in these virgin SFO products. Major Conclusions: 1H NMR analysis provides much valuable molecular information regarding the composition and virginal status of SFOs.The high [MUFA]:[PUFA] content ratio of unrefined EAV SFO products renders them more suitable and safer for commercial or domestic deep-frying episodes than refined SFOs (MUFAs are much more resistant to thermally-induced peroxidation than PUFAs). These products also potentially offer valuable health benefits in view of their high natural sterol and stanol contents.
Apr 2017 DOI 10.14302/issn.2377-2549.jndc-17-1488
H.SaleemCorresponding author
Department of Physics, Annamalai University, Annamalainagar 608 002, Tamil Nadu, India
The compound 2-(4-methoxyphenyl)-2, 3-dihydro-1H-perimidine (MPDP) was synthesized. The molecular structure and its functional groups were characterized with the help of Fourier Transform Infrared: FTIR/ Fourier Transform FT-Raman spectra in the regions of 400-4000/50-4000cm-1, respectively. The geometrical parameters, harmonic vibrational wavenumbers, Infrared (IR) & Raman scattering intensities, Nuclear Magnetic Resonance (NMR) chemical shift and Ultraviolet-Visible (UV-Vis) spectra were computed using B3LYP/6-311++G(d,p) level of theory. The complete vibrational analysis were made on the basis of Potential energy distribution (PED) calculation with the help of VEDA4 programme. The Highest occupied molecular orbital (HOMO) – Lowest unoccupied molecular orbital (LUMO) energy gap and intra-molecular charge transfer (ICT) were studied using NBO analysis. The first order hyperpolarizability (β0) and other related properties (β, α0, Δα) of MPDP were computed. The molecular electrostatic potential (MEP), Mulliken atomic charges were calculated using the same level of theory. In addition, the various thermodynamic parameters were also calculated.
Feb 2016 DOI 10.14302/issn.2471-2140.jaa-15-887
Alabdul Magid AbdulmagidCorresponding author
ICMR-UMR CNRS 7312, Groupe Isolement et Structure, Campus Sciences, Bât. 18, BP 1039, 51687 Reims Cedex 2, France
A bioassay-guided fractionation of petroleum ether, EtOAc and n-BuOH soluble parts of the 80% hydromethanol extract was performed to investigate the antioxidant activity of Secamoneafzeliiaerial parts using DPPH free radical scavenging assay. The results revealed that EtOAc and n-BuOH soluble parts have moderate to good DPPH radical scavenging activity (EC50 = 139.3 and 30.5 μg/mL, respectively). Therefore, from the most active fractions of EtOAc and n-BuOH soluble parts were isolated two new flavonoid diglycosides quercetin-3-O-β-d-apiofuranosyl-(1→2)-α-l-rhamnopyranoside and genkwanin-8-C-β-d-apiofuranosyl-(1→2)-β-d-glucopyranoside in addition to nine known compounds (2-10). Their structures were elucidated on the basis of spectroscopic data including 1D- and 2D-NMR and ESI-MS. The ability of the isolated compounds to scavenge the DPPH was evaluated. The new compound 1, quercitrin (3) and rutin (6) have antioxidant potential with EC50 values ranging from 8.4 to 13.6 µg/mL, compared to the standard ascorbic acid (EC50 7.4 µg/mL).