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Navindra P. Seeram - One of the best experts on this subject based on the ideXlab platform.
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cosmetic applications of glucitol core containing gallotannins from a proprietary phenolic enriched red maple Acer Rubrum leaves extract inhibition of melanogenesis via down regulation of tyrosinase and melanogenic gene expression in b16f10 melanoma cells
Archives of Dermatological Research, 2017Co-Authors: Nicholas A Dasilva, Ling Wang, Zhengxi Wei, Liangran Guo, Shelby L Johnson, Navindra P. SeeramAbstract:The red maple (Acer Rubrum) is a rich source of phenolic compounds which possess galloyl groups attached to different positions of a 1,5-anhydro-d-glucitol core. While these glucitol-core containing gallotannins (GCGs) have reported anti-oxidant and anti-glycative effects, they have not yet been evaluated for their cosmetic applications. Herein, the anti-tyrosinase and anti-melanogenic effects of a proprietary phenolic-enriched red maple leaves extract [Maplifa™; contains ca. 45% ginnalin A (GA) along with other GCGs] were investigated using enzyme and cellular assays. The GCGs showed anti-tyrosinase activity with IC50 values ranging from 101.4 to 1047.3 μM and their mechanism of tyrosinase inhibition (using GA as a representative GCG) was evaluated by chelating and computational/modeling studies. GA reduced melanin content in murine melanoma B16F10 cells by 79.1 and 56.7% (at non-toxic concentrations of 25 and 50 μM, respectively), and its mechanisms of anti-melanogenic effects were evaluated by using methods including fluorescent probe (DCF-DA), real-time PCR, and western blot experiments. These data indicated that GA was able to: (1) reduce the levels of reactive oxygen species, (2) down-regulate the expression of MITF, TYR, TRP-1, and TRP-2 gene levels in a time-dependent manner, and (3) significantly reduce protein expression of the TRP-2 gene. Therefore, the anti-melanogenic effects of red maple GCGs warrant further investigation of this proprietary natural product extract for potential cosmetic applications.
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Anticancer studies of gallotannins from Maple (Acer) Spp
Planta Medica, 2012Co-Authors: Antonio González-sarrías, Tao Yuan, Navindra P. SeeramAbstract:Gallotannins are hydrolyzable tannins found in higher plants. Here we conducted anticancer and structure activity related studies of twelve gallotannins isolated from sugar (Acer saccharum) and red (Acer Rubrum) maple species. The gallotannins, ginnalins A-C and maplexins A-I, differ in the number of galloyl groups connected to a 1,5-anhydro-D-glucitol core. The gallotannins were evaluated for antiproliferative effects against human colon (HCT-116) and breast (MCF-7) cancer cells. While the gallotannins with one galloyl group were not active, those with two galloyls were more active than those with three galloyls (IC50=28–50 vs. 64–112µg/mL). Also, maplexins C-D, which contained two galloyls, induced apoptosis and arrested cell cycle (in S-phase) of the cancer cell lines. Thus, the anticancer effects of maple gallotannins are influenced by the number of galloyl groups and are mediated by apoptosis and cell cycle arrest.
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Cytotoxicity and structure activity relationship studies of maplexins A-I, gallotannins from red maple (Acer Rubrum).
Food and Chemical Toxicology, 2012Co-Authors: Antonio González-sarrías, Tao Yuan, Navindra P. SeeramAbstract:Abstract Maplexins A–I are a series of structurally related gallotannins recently isolated from the red maple ( Acer Rubrum ) species. They differ in number and location of galloyl derivatives attached to 1,5-anhydro-glucitol. Here, maplexins A–I were evaluated for anticancer effects against human tumorigenic (colon, HCT-116; breast, MCF-7) and non-tumorigenic (colon, CCD-18Co) cell lines. The maplexins which contained two (maplexins C–D) or three (maplexins E–I) galloyl derivatives each, inhibited cancer cell growth while those with only one galloyl group (maplexins A-B) did not. Moreover, maplexins C–D showed greater antiproliferative effects than maplexins E–I (IC 50 = 59.8–67.9 and 95.5–108.5 μM vs. 73.7–165.2 and 115.5–182.5 μM against HCT-116 and MCF-7 cells, respectively). Notably, the cancer cells were up to 2.5-fold more sensitive to the maplexins than the normal cells. In further mechanistic studies, maplexins C–D (at 75 μM concentrations) induced apoptosis and arrested cell cycle (in the S-phase) of the cancer cells. These results suggest that the number of galloyl groups attached to the 1,5-anhydro-glucitol moiety in these gallotannins are important for antiproliferative activity. Also, this is the first in vitro anticancer study of maplexins.
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new maplexins f i and phenolic glycosides from red maple Acer Rubrum bark
Tetrahedron, 2012Co-Authors: Tao Yuan, Navindra P. SeeramAbstract:Abstract Four new gallotannins, maplexins F–I (1–4), two new phenolic glycosides, Rubrumosides A–B (5,6), and eleven known compounds were isolated from red maple (Acer Rubrum) bark. Their structures were elucidated based on spectroscopic analysis. The maplexins contained three galloylated derivatives attached to different positions of 1,5-anhydro-glucitol and were 10–20 fold more potent α-glucosidase inhibitors than the clinical drug, Acarbose (IC50=7–16 vs 161 μM), in vitro. These results support previous data suggesting that gallotannins are the main contributors to the α-glucosidase inhibitory activities of maple plant part extracts and that three substituents on the 1,5-anhydro-glucitol moiety are important for activity.
Tatjana Stevanovic - One of the best experts on this subject based on the ideXlab platform.
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Nutrients, Antioxidant Capacity and Safety of Hot Water Extract from Sugar Maple (Acer saccharum M.) and Red Maple (Acer Rubrum L.) Bark
Plant Foods for Human Nutrition, 2018Co-Authors: Sagar Bhatta, Cristina Ratti, Patrice E. Poubelle, Tatjana StevanovicAbstract:Sugar maple ( Acer saccharum M.) and red maple ( Acer Rubrum L.) barks were treated with hot water to extract nutrients in order to explore, for the first time, its potential as safe dietary antioxidants. The organic and inorganic nutrients of these extracts, as well as their safety on human PLB-985 cells differentiated into neutrophils-like cells, were determined. Proximate analysis showed that both bark extracts were low in moisture and fat. Sugar maple bark extract (SM-BX) showed crude protein and ash content higher than those found in red maple bark extract (RM-BX). In addition, SM-BX had total sugars higher than those evaluated in RM-BX, while complex sugars (oligo- and/or poly-saccharides) were similarly abundant in both bark extracts. Furthermore, SM-BX demonstrated a wide array of vital minerals (K, Ca, Mg, P, Na, Fe and Cu) in quantity larger than that evaluated in RM-BX, whereas RM-BX have Zn and Mn levels higher than those found in SM-BX. Phytochemical analyses showed that RM-BX exhibited total phenolic and flavonoid contents higher than those measured in SM-BX. Consequently, RM-BX presented an antioxidant activity higher than that of SM-BX: 2.85-fold ABTS radical cation scavenging capacity and 1.9-fold oxygen radical absorbance capacity. Finally, RM-BX and SM-BX were greatly safe since, at concentration up to 100 μg/ml, they did not modify the viability of neutrophils as determined by flow-cytometry assay using Annexin V-FITC/Propidum Iodide as markers. In conclusion, our in vitro studies indicate that both red and sugar maple bark extracts have a real potential as food additives.
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hot water extraction optimization of sugar maple Acer saccharum marsh and red maple Acer Rubrum l bark applying principal component analysis
Journal of Wood Chemistry and Technology, 2017Co-Authors: Thibaud R Geoffroy, Yves Fortin, Tatjana StevanovicAbstract:In the forest industry, bark is an abundant residue, predominantly converted into calorific energy. As the antioxidant potential of phenolic compounds from sugar maple (Acer saccharum Marsh.) and red maple (Acer Rubrum L.) bark has previously been established, the present study focused on the hot-water extraction optimization of these barks. Several process parameters (maple species, temperature, duration, ratio bark/water, particle size) were thus studied and large disparities were found between the two species. Extraction yield, phenolic content, and antioxidant capacity of red maple extracts were several times higher than those of sugar maple extracts. Principal component analysis, applied to the selected best extraction conditions, identified 3–4 clusters depending on the maple species. These groups were sorted from the highest extraction yield and energy consumption combined with the lowest phenolic content and antioxidant capacity, to moderate extraction yield and energy consumption with the highest...
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polyphenol contents and radical scavenging capacities of red maple Acer Rubrum l extracts
Food and Chemical Toxicology, 2011Co-Authors: Mariana Royer, Papa Niokhor Diouf, Tatjana StevanovicAbstract:The crude ethanol and water extracts of different red maple (Acer Rubrum L.) tissues: whole branches (WB), wood of branches (BW), bark of branches (BB), stem bark (SB) and whole twigs (T), were examined in order to determine their phenolic contents as well as their radical scavenging capacities. The total phenols (TP), total extractable tanins (TET) and non-precipitable phenols (NPP), were determined by combination of spectrophotometric and precipitation methods, while total flavonoids, hydroxy cinanmic acids and proanthocyanidins were determined spectrophotometrically. The radical scavenging activities of the extracts were determined against five reactive oxygen species (ROS): superoxide anion (O2·-), hydroxyl radical (HO), peroxyl radical (ROO), hypochlorite ion (ClO−), and hydrogen peroxide (H2O2) and one reactive nitrogen species (RNS): nitric oxide (NO). The extracts of stem bark were significantly more efficient (exhibiting the highest antioxidant efficiencies, AE) than the other studied extracts against all ROS (at p < 0.05, Duncan statistical tests), except against NO. The correlation coefficients determined between total phenolic (TP) content and antiradical efficiencies were R2 = 0.12 for O2·-; R2 = 0.29 for HO; R2 = 0.40 for H2O2; R2 = 0.86 for ROO; R2 = 0.03 for NO and R2 = 0.73 for ClO−. Our results indicate potential utilisation of extracts as natural antioxidants.
J T Arnason - One of the best experts on this subject based on the ideXlab platform.
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ethyl m digallate from red maple Acer Rubrum l as the major resistance factor to forest tent caterpillar malacosoma disstria hbn
Journal of Chemical Ecology, 2001Co-Authors: Mamdouh M Abouzaid, B V Helson, Constance Nozzolillo, J T ArnasonAbstract:An ethanolic extract of red maple (Acer Rubrum L.) leaves (RME) applied to trembling aspen (Populus tremuloides Michx.) leaves reduced feeding in choice test assays with forest tent caterpillar larvae (Malacosoma disstria Hbn.) (FTC), whereas a trembling aspen foliage extract, similarly applied, stimulated feeding. Compounds isolated from the RME were gallic acid, methyl gallate, ethyl gallate, m-digallate, ethyl m-digallate, 1-O-galloyl-β-D-glucose, 1-O-galloyl-α-L-rhamnose, kaempferol 3-O-β-D-glucoside, kaempferol 3-O-β-D-galactoside, kaempferol 3-O-β-L-rhamnoside, kaempferol-3-O-rhamnoglucoside, quercetin 3-O-β-D-glucoside, quercetin 3-O-β-L-rhamnoside and quercetin 3-O-rhamnoglucoside, (−)-epicatechin, (+)-catechin and ellagic acid. All of the gallates, (−)-epicatechin, and kaempferol 3-O-β-L-rhamnoside deterred feeding on trembling aspen leaf disks when applied at 0.28 mg/cm2. The two digallates deterred feeding by 90% and were the most effective. HPLC analysis indicated that ethyl m-digallate is present in amounts 10–100 × higher in RME (∼2.5–250 mg/g) than any other compound. Thus, ethyl m-digallate appears to be the major compound protecting red maple from feeding by FTC, with a minor contribution from other gallates.
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ethyl m digallate from red maple Acer Rubrum l as the major resistance factor to forest tent caterpillar malacosoma disstria hbn
Journal of Chemical Ecology, 2001Co-Authors: Mamdouh M Abouzaid, B V Helson, Constance Nozzolillo, J T ArnasonAbstract:An ethanolic extract of red maple (Acer Rubrum L.) leaves (RME) applied to trembling aspen (Populus tremuloides Michx.) leaves reduced feeding in choice test assays with forest tent caterpillar larvae (Malacosoma disstria Hbn.) (FTC), whereas a trembling aspen foliage extract, similarly applied, stimulated feeding. Compounds isolated from the RME were gallic acid, methyl gallate, ethyl gallate, m-digallate, ethyl m-digallate, 1-O-galloyl-beta-D-glucose, 1-O-galloyl-alpha-L-rhamnose, kaempferol 3-O-beta-D-glucoside, kaempferol 3-O-beta-D-galactoside, kaempferol 3-O-beta-L-rhamnoside, kaempferol-3-O-rhamnoglucoside, quercetin 3-O-beta-D-glucoside, quercetin 3-O-beta-L-rhamnoside and quercetin 3-O-rhamnoglucoside, (-)-epicatechin. (+)-catechin and ellagic acid. All of the gallates, (-)-epicatechin, and kaempferol 3-O-beta-L-rhamnoside deterred feeding on trembling aspen leaf disks when applied at 0.28 mg/cm2. The two digallates deterred feeding by 90% and were the most effective. HPLC analysis indicated that ethyl m-digallate is present in amounts 10-100 x higher in RME (approximately 2.5-250 mg/g) than any other compound. Thus, ethyl m-digallate appears to be the major compound protecting red maple from feeding by FTC, with a minor contribution from other gallates.
Noriaki Murakami - One of the best experts on this subject based on the ideXlab platform.
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Ecology and Evolutionary Biology and
2016Co-Authors: Ikuyo Saeki, Burton V Barnes, Christopher W Dick, Noriaki MurakamiAbstract:Comparative phylogeography of red maple (Acer Rubrum L.) and silver maple (Acer saccharinum L.): impacts of habitat specialization, hybridization and glacial histor
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comparative phylogeography of red maple Acer Rubrum l and silver maple Acer saccharinum l impacts of habitat specialization hybridization and glacial history
Journal of Biogeography, 2011Co-Authors: Ikuyo Saeki, Burton V Barnes, Christopher W Dick, Noriaki MurakamiAbstract:Aim We analysed variation in chloroplast DNA (cpDNA) in red maple (Acer Rubrum L.) and silver maple (Acer saccharinum L.) across a large part of their geographic ranges. Acer Rubrum is one of the most common and morphologically variable deciduous trees of eastern North America, while its sister species A. saccharinum has a more restricted habitat distribution and displays markedly less morphological variation. Our objective was to infer the impact of biogeographic history on cpDNA diversity and phylogeographic structure in both species. Location Deciduous forests of eastern North America. Methods We sequenced 1289 to 1645 bp of non-coding cpDNA from A. Rubrum (n = 258) and A. saccharinum (n = 83). Maximum parsimony networks and spatial analysis of molecular variance (SAMOVA) were used to analyse phylogeographic structure. Rarefaction analyses were used to compare genetic diversity. Results A total of 40 cpDNA haplotypes were recovered from A. Rubrum (38 haplotypes) and A. saccharinum (7 haplotypes). Five of the seven A. saccharinum haplotypes were shared with nearby samples of A. Rubrum. SAMOVA recovered four phylogeographic groups for A. Rubrum in: (1) south-eastern USA, (2) the Gulf and south-eastern Coastal Plain, (3) the lower Mississippi River Valley, and (4) the central and northern regions of eastern North America. Acer saccharinum had significantly lower haplotype diversity than A. Rubrum, and novel haplotypes in post-glaciated northern limits of its range were shared with A. Rubrum. Main conclusions This is the first study of A. Rubrum to report a distinct phylogeographic group centred on the lower Mississippi River, and the first to examine data comparatively with A. saccharinum. We hypothesized that A. Rubrum would display stronger phylogeographic structure and greater haplotype diversity than A. saccharinum because of its greater geographic range, and ecological and morphological variation. This hypothesis was supported by the cpDNA analysis. The sharing of cpDNA and chloroplast simple sequence repeat (cpSSR) haplotypes in areas of geographic overlap provides evidence of introgression, which led to an increase in haplotype diversity in both species, and to novel phylogeographic structure in A. Rubrum. We recommend that introgression be considered, along with other potential causes, as an explanation for the phylogeographic structure of cpDNA in plants.
Ikuyo Saeki - One of the best experts on this subject based on the ideXlab platform.
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Ecology and Evolutionary Biology and
2016Co-Authors: Ikuyo Saeki, Burton V Barnes, Christopher W Dick, Noriaki MurakamiAbstract:Comparative phylogeography of red maple (Acer Rubrum L.) and silver maple (Acer saccharinum L.): impacts of habitat specialization, hybridization and glacial histor
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comparative phylogeography of red maple Acer Rubrum l and silver maple Acer saccharinum l impacts of habitat specialization hybridization and glacial history
Journal of Biogeography, 2011Co-Authors: Ikuyo Saeki, Burton V Barnes, Christopher W Dick, Noriaki MurakamiAbstract:Aim We analysed variation in chloroplast DNA (cpDNA) in red maple (Acer Rubrum L.) and silver maple (Acer saccharinum L.) across a large part of their geographic ranges. Acer Rubrum is one of the most common and morphologically variable deciduous trees of eastern North America, while its sister species A. saccharinum has a more restricted habitat distribution and displays markedly less morphological variation. Our objective was to infer the impact of biogeographic history on cpDNA diversity and phylogeographic structure in both species. Location Deciduous forests of eastern North America. Methods We sequenced 1289 to 1645 bp of non-coding cpDNA from A. Rubrum (n = 258) and A. saccharinum (n = 83). Maximum parsimony networks and spatial analysis of molecular variance (SAMOVA) were used to analyse phylogeographic structure. Rarefaction analyses were used to compare genetic diversity. Results A total of 40 cpDNA haplotypes were recovered from A. Rubrum (38 haplotypes) and A. saccharinum (7 haplotypes). Five of the seven A. saccharinum haplotypes were shared with nearby samples of A. Rubrum. SAMOVA recovered four phylogeographic groups for A. Rubrum in: (1) south-eastern USA, (2) the Gulf and south-eastern Coastal Plain, (3) the lower Mississippi River Valley, and (4) the central and northern regions of eastern North America. Acer saccharinum had significantly lower haplotype diversity than A. Rubrum, and novel haplotypes in post-glaciated northern limits of its range were shared with A. Rubrum. Main conclusions This is the first study of A. Rubrum to report a distinct phylogeographic group centred on the lower Mississippi River, and the first to examine data comparatively with A. saccharinum. We hypothesized that A. Rubrum would display stronger phylogeographic structure and greater haplotype diversity than A. saccharinum because of its greater geographic range, and ecological and morphological variation. This hypothesis was supported by the cpDNA analysis. The sharing of cpDNA and chloroplast simple sequence repeat (cpSSR) haplotypes in areas of geographic overlap provides evidence of introgression, which led to an increase in haplotype diversity in both species, and to novel phylogeographic structure in A. Rubrum. We recommend that introgression be considered, along with other potential causes, as an explanation for the phylogeographic structure of cpDNA in plants.
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occurrence and landscape ecology of a rare disjunct maple species Acer pycnanthum and comparison with Acer Rubrum
Environmental Reviews, 2004Co-Authors: Burton V Barnes, Ikuyo Saeki, Asako KitazawaAbstract:Japanese red maple, Acer pycnanthum K. Koch, is the disjunct sister species of the red maple, Acer Rubrum L. Whereas A. Rubrum is one of the most widely distributed and abundant species in eastern North America, A. pycnanthum is rare in central Honshu, Japan. Although its morphological similarity to A. Rubrum is well known, little is known about the sites and communities where it occurs, its natural history characteristics, sexual and asexual regeneration, and the reasons for its restricted occurrence. We located and described all known sites, totaling <18 ha, which supported populations of three or more clones. Twenty-seven of the 30 ecosystems described are remnant natural populations, which are confined to lower slopes of three river basins where wetlands have persisted and recurrently formed for millions of years due to unique geological, topographic, and soil properties. Acer pycnanthum, an obligate species of forested wetlands, occurs on diverse seepage and floodplain ecosystems that are characteriz...