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Authors: Ariene A. Leme , Cristina M.P. Vidal , A.B.S. Sousa , Rasika Phansalkar , Joo-Won Nam ORCID , Jonathan Bisson ORCID , Shao-Nong Chen ORCID , Guido F. Pauli ORCID , Ana Bedran-Russo
Journal: Dental Materials (RoMEO status: Green)
Subjects:
NMR
Plant derived proanthocyanidins are well-established compounds exhibiting high dentin biomodification potency. Among the effects, enhanced tissue biomechanics and biostability are of relevance to restorative dentistry. This study evaluated the adhesive properties of an enriched proanthocyanidin primer on the bond strength of experimental resin-based adhesives containing variable concentrations of HEMA.

categories publications science
Authors: Joo-Won Nam ORCID , Rasika Phansalkar , David C. Lankin ORCID , Jonathan Bisson ORCID , James McAlpine , Ariene A. Leme , Cristina M.P. Vidal , Benjamin Ramirez , Matthias Niemitz ORCID , Ana Bedran-Russo , Shao-Nong Chen ORCID , Guido F. Pauli ORCID
Journal: Journal of Organic Chemistry (RoMEO status: White)
Subjects:
NMR
The ability of certain oligomeric proanthocyanidins (OPACs) to enhance the biomechanical properties of dentin involves collagen cross-linking of the 1.3–4.5 nm wide space via protein–polyphenol interactions. A systematic interdisciplinary search for the bioactive principles of pine bark has yielded the trimeric PAC, ent-epicatechin-(4β→8)-epicatechin-(2β→O→7,4β→8)-catechin (3), representing the hitherto most potent single chemical entity capable of enhancing dentin stiffness. Building the case from two congeneric PAC dimers, a detailed structural analysis decoded the stereochemistry, spatial arrangement, and chemical properties of three dentin biomodifiers.
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categories publications science

# Posters/

Chemical nano shifts explain the NMR fingerprints of dentin-enhancing oligomeric proanthocyanidins

1D NMR spectra contain a wealth of vital structural information that can enhance the description of bioactive molecules. The present study demonstrates how quantum-mechanics driven 1H iterative Full Spin Analysis (QM-HiFSA) is capable of distinguishing spectral detail that cannot be interpreted manually or visually, but provides important information of the 3D structure and bonding (re-)activity of the molecules. This approach is established by analyzing 1D NMR spectra of oligomeric proanthocyanidins (OPACs), which exhibit high dentin bioactivity, and were isolated from the inner bark of pine.
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# Posters/

K-targeted isolation of C-glycosylflavones from Vitex agnus-castus by countercurrent methodology

C-glycosylated flavones, including orientin, isoorientin, vitexin, and isovitexin, are minor but biologically significant constituents of fruit extracts of the chaste-tree (Vitex agnus-castus L.), a botanical supplement used to treat PMS and postmenopausal symptoms. The partition coefficient, or K-value, is the ratio of the concentration of a compound in each phase of a biphasic solvent mixture and is a physicochemical property of a particular compound in a particular solvent system. This value can be used to predict retention volume (V ret) in a countercurrent separation procedure.
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category posters
Authors: Ariene A. Leme , Cristina M.P. Vidal , Thaiane R. Aguiar , A.B.S. Sousa , Rasika Phansalkar , Joo-Won Nam ORCID , Jonathan Bisson ORCID , Shao-Nong Chen ORCID , Guido F. Pauli ORCID , Ana Bedran-Russo
Journal: Dental Materials (RoMEO status: Green)
Subjects:
NMR
The polyphenol source and molecular structure complexity affects interactions of proanthocyanidins (PACs) with dentin matrix. Therefore, this study evaluated the dentin bioactivity of compounds from a non-galloylated PACs-rich extract.

categories publications science