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Natsuki Ganeko Nana Kato Saki Watanabe Februadi Bastian Masateru Miyake 《Bioscience, biotechnology, and biochemistry》2019,83(4):605-608
In the current study, we isolated a proanthocyanidin oligomer from the hulls of red-kerneled rice. The structure of the oligomer was characterized based on spectral data and chemical reaction. Furthermore, two anthocyanins were isolated from the beards of the same source. The proanthocyanidins and beard extract showed more potent inhibitory and cleaving activities than those of positive controls, respectively. 相似文献
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Yumi Nakamura Takatsugu Tsuchiya Mariko Hara-Chikuma Masato Yasui Yuko Fukui 《Biochemistry and Biophysics Reports》2020
In a previous clinical study, the moisture content in the stratum corneum of healthy Japanese women who consumed a beverage rich in oligomeric proanthocyanidins (OPCs) made from red wine extract was found to be higher than that in the control group. This finding suggested that OPCs can increase skin moisture content. In this study, we determined the expression level of aquaporin-3 (AQP3) in keratinocytes to elucidate the mechanism by which compounds in red wine grape increase moisture content in stratum corneum. Through in vitro studies, we confirmed that normal human epidermal keratinocytes (NHEK) incubated with red wine induced AQP3 expression. Furthermore, the supplementation of red wine fractions enriched in OPC was shown to increase AQP3 expression. Besides, the component of OPC-rich fractions that upregulated AQP3 expression was found to be a gallic acid (GA)-binding flavan-3-ol, particularly oligomeric compounds. We found that GA-binding OPC were able to upregulate AQP3 expression and that these compounds were enriched in red wine. Our findings might suggest that the mechanism of enhancement of moisture content in stratum corneum by red wine might be via the upregulation of AQP3 expression in the epidermal keratinocytes. 相似文献
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Bengt F. Nyman 《Phytochemistry》1985,24(12):2939-2944
Successful protein extractions from Scots pine needles in different buffers (pH 5–9)with PVP-10 and Tween 80 suggest that both hydrogen bonds and hydrophobic interactions are responsible for the formation of insoluble protein-tannin complexes. Gel filtrations did not permit a separation of tannins from solubilized proteins. Contamination of the protein fractions was attributed to proanthocyanidins, both as such and when attached to the proteins. The ability of the soluble protein-proanthocyanidin complexes to adsorb on both Polyclar AT through hydrogen bonding and on Phenyl-Sepharose CL-4B through hydrophobic interactions suggests an amphiphilic capacity on the part of the proanthocyanidin. The factors causing persistent binding between proteins and proanthocyanidins through hydrophobic interactions are discussed. Although the vanillin test confirmed the presence of high molecular weight tannins, they occurred independently of the proteins. 相似文献
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F. E. Kandil L. Song J. M. Pezzuto K. Marley D. S. Seigler M. A. L. Smith 《In vitro cellular & developmental biology. Plant》2000,36(6):492-500
Summary The extraction, fractionation, and chromatographic separation of a series of proanthocyanidin monomers and oligomers were
facilitated using a flavonoid-rich cell culture of Vaccinium pahalae Skottsberg as the donor tissue. The cell cultures, after exposure to light, readily accumulated anthocyanin pigments and
other flavonoids in relatively large amounts, with minimal concurrent production of pectins, enzymes, and complex sugars produced
in field-grown Vaccinium berries. The absence of these interfering compounds greatly simplified the isolation and purification of proanthocyanidins
and other phenolic compounds from cell cultures, primarily using vacuum chromatography. Subsequently, the structures and molecular
weights of several individual compounds and the general composition of unresolved fractions were established with 1H- and 13C-NMR and MS. The initial extract of V. pahalae cell cultures was readily fractionated on silica gel to yield a series of fractions containing proanthocyanidin B-2, a series
of increasingly polar proanthocyanidin oligomers ranging from dimers to heptamers largely based on (−)-epicatechin structures
(some with A-type linkages), a mixture of E- and Z-p-coumaric acid, the corresponding 4-O-glucoside, and other compounds containing E- and Z-p-coumaric acid moieties. Cell culture extracts demonstrated broad antioxidant capacity and significant ability to inhibit
tumor promotion in vitro, as indicated in an ornithine decarboxylase assay. 相似文献