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Dennis M Reinecke - One of the best experts on this subject based on the ideXlab platform.
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developmental profile of anthocyanin flavonol and proanthocyanidin type content and localization in saskatoon fruits Amelanchier alnifolia nutt
Journal of Agricultural and Food Chemistry, 2015Co-Authors: Alena L Jin, Jocelyn A Ozga, James A Kennedy, Jayma L Koernersmith, Gabor Botar, Dennis M ReineckeAbstract:Saskatoons (Amelanchier alnifolia Nutt.) are small fruits that contain substantial quantities of flavonoids. To further characterize and understand the role of these flavonoids during fruit development, anthocyanins, flavonols, and proanthocyanidins were identified, quantified, and localized over development in cultivars that produce blue-purple or white fruit at maturity. Anthocyanin content was low in young fruit and then dramatically increased as the fruit transitioned into ripening only in the pigmented-fruit (blue-purple) cultivars. Proanthocyanidins with both A-type and B-type linkages were detected in fruit, with (-)-epicatechin as the most abundant proanthocyanidin subunit. Flavonol and proanthocyanidin content was high in, and localized throughout, the tissues of young fruit and in the developing seed coats, with levels decreasing as the fruit expanded. Our data show that flavonoid type, content, and tissue localization vary throughout development in saskatoon fruit. These data can be used to target specific fruit developmental stages and flavonoid classes for optimization of health-beneficial flavonoid content.
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characterization of cyanidin and quercetin derived flavonoids and other phenolics in mature saskatoon fruits Amelanchier alnifolia nutt
Journal of Agricultural and Food Chemistry, 2007Co-Authors: Jocelyn A Ozga, Asma Saeed, Wendy Wismer, Dennis M ReineckeAbstract:In order to further characterize the anthocyanins, flavonols, and other phenolics present in mature saskatoon (Amelanchier alnifolia Nutt.) fruit, extracts were characterized using high-performance liquid chromatography, gas chromatography, and liquid chromatography–mass spectrometry. Cyanidin 3-O-galactoside, cyanidin 3-O-glucoside, cyanidin 3-O-arabinoside, and cyanidin 3-O-xyloside were identified as the four major anthocyanins in the mature fruit. The quercetin-derived flavonols, quercetin 3-O-glucoside, quercetin 3-O-galactoside, quercetin 3-O-arabinoside, quercetin 3-O-xyloside, quercetin 3-O-arabinoglucoside, quercetin 3-O-robinobioside, and quercetin 3-O-rutinoside were also identified in mature fruit extracts. In addition, two chlorogenic acid isomers (hydroxycinnamates), 3-O-caffeoylquinic acid and 5-O-caffeoylquinic acid were detected. The total content of the anthocyanin-, flavonol-, and hydroxycinnamate-type phenolics detected in mature ‘Smoky’ saskatoon fruit was 140, 25, and 96 mg/100 g fre...
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anthocyanins and nutrient components of saskatoon fruits Amelanchier alnifolia nutt
Canadian Journal of Plant Science, 2006Co-Authors: Jocelyn A Ozga, Asma Saeed, Dennis M ReineckeAbstract:The benefits of fruits and vegetables in human health have long been recognized. Part of the beneficial effects of these foods on human health has been purported to be due to various polyphenolic compounds that have radical scavenging and antioxidant activity. Saskatoon fruits (Amelanchier alnifolia Nutt.) are native to Western Canada and are an emerging North American fruit crop. The blue-purple coloration of mature saskatoon fruit, an important quality characteristic, is due to the presence of anthocyanins, which are a class of polyphenolic compounds that contribute to protection against human diseases. The objective o f this review is to summarize the research on anthocyanins, a potential nutraceutical, and other nutrient components in saskatoon fruits. In addition, management practices to increase anthocyanin content in the mature fruit are discussed. Key words: Amelanchier alnifolia, saskatoon, fruit quality, chemical composition, anthocyanins
David D. Kitts - One of the best experts on this subject based on the ideXlab platform.
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Dehydration Techniques Affect Phytochemical Contents and Free Radical Scavenging Activities of Saskatoon berries (Amelanchier alnifolia Nutt.)
Journal of Food Science, 2006Co-Authors: B.h.l. Kwok, Chun Hu, Timothy D. Durance, David D. KittsAbstract:ABSTRACT: Saskatoon berries (Amelanchier alnifolia Nutt., cv. Thiessen and Smoky) were dehydrated using freeze-drying (FD), vacuum microwave drying (VMD), air-drying (AD), and a combination of air-drying and vacuum microwave drying (CD) methods. All processed berries had significantly reduced (P < 0.05) total phenolics and anthocyanin contents in addition to reduced antioxidant activities, as compared with fresh frozen (FF) berries. FD berries rendered the highest amount (P < 0.05) of anthocyanin and antioxidant activities, followed by VMD berries. The CD dehydration resulted in intermediate results between VMD and AD. The substantial decrease in both total phenolics and anthocyanin content in berries was corresponded to significant (P < 0.05) losses in antioxidant capacities measure in different model systems.
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saskatoon berries Amelanchier alnifolia nutt scavenge free radicals and inhibit intracellular oxidation
Food Research International, 2005Co-Authors: B.h.l. Kwok, David D. KittsAbstract:Two cultivars (Thiessen and Smoky) of Saskatoon berries (Amelanchier alnifolia Nutt.) possess free radical scavenging activities in a concentration-dependent manner, whereas Thiessen presented higher (p < 0.05) activity compared to Smoky due to its relatively abundant anthocyanin content. Total anthocyanin content significantly corresponded to free radical scavenging activities (p < 0.05). Solvent fractionation revealed that the free radical scavenging components, i.e., anthocyanin, predominantly occurred in the ethyl acetate and n-butanol extracted fractions, suggesting that active components are more likely to occur in glycoside forms. HPLC further confirmed the existence of cyanidin-3-O-galactoside and cyanidin-3-O-glucoside as leading anthocyanins in the Saskatoon berries. Furthermore, Saskatoon berries extracts from both cultivars suppressed peroxy-radical induced intracellular oxidation in a concentration-dependent manner without affecting cell viability. The obtained results provided useful information for the future application of Saskatoon berries in the nutraceutical industry.
Christopher S Campbell - One of the best experts on this subject based on the ideXlab platform.
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phylogenetic relationships and chloroplast capture in the Amelanchier malacomeles peraphyllum clade maleae rosaceae evidence from chloroplast genome and nuclear ribosomal dna data using genome skimming
Molecular Phylogenetics and Evolution, 2020Co-Authors: Binbin Liu, Christopher S Campbell, Deyuan Hong, Jun WenAbstract:The Amelanchier-Malacomeles-Peraphyllum (AMP) clade consists of ca. 26 species distributed in North and Central America, Europe, Asia, and northwestern Africa. While molecular and morphological data strongly support this clade, relationships of its genera are uncertain. Support for the monophyly of Amelanchier and for the phylogenetic positions of Malacomeles and Peraphyllum has varied between studies. Our goals were to reconstruct a robust phylogeny of the AMP clade in the framework of Maleae and clarify the phylogenetic placements of Malacomeles and Peraphyllum. This study employs sequences of the whole plastome and nuclear ribosomal DNA (nrDNA) repeats assembled using genome skimming with 131 samples representing 115 species in 31 genera of Rosaceae, especially Maleae. Maximum likelihood (ML) and Bayesian analysis (BI) of whole plastome datasets strongly supported Amelanchier as not monophyletic, with Peraphyllum sister to eastern North American Amelanchier and Malacomeles sister to the western North American-Eurasian Amelanchier. In contrast, nrDNA recovered the monophyly of Amelanchier, with Peraphyllum sister to Amelanchier and Malacomeles sister to the Amelanchier-Peraphyllum clade. The strong topological conflicts between plastome and nrDNA phylogenies of Peraphyllum and of Malacomeles are best explained by ancient chloroplast capture that occurred in SW North America.
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species delimitation in tetraploid apomictic Amelanchier rosaceae
Systematic Botany, 2017Co-Authors: Kevin R. Cushman, Michael B. Burgess, Eric T. Doucette, Gretchen A Nelson, Christopher S CampbellAbstract:Diversification in Amelanchier tetraploid apomicts differs from that of diploid sexuals and produces groups that are taxonomically difficult. Apomixis facilitates expansion of ecologically successful genotypes into numerous, narrowly distributed, and often minimally distinct microspecies. Residual sexuality in tetraploids creates hybrid swarms and intergradation of taxa. This gene flow is evident in DNA sequences from nuclear and chloroplast regions that record mostly allotetraploid, convoluted histories. Ongoing apomixis in successful tetraploid genotypes fosters their expansion into geographically widespread phenotypic clusters.We delimit such clusters as species and deny species status to microspecies.We demonstrate polyploid complexity and our approach to species delimitation in three taxa of Amelanchier. The tetraploid microspecies A. “rubra” of southeastern Maine, while morphologically distinct, hybridizes with sympatric congeners. Eastern North American A. bartramiana contains diploids and polyploids (tetraploids and a few triploids) that are sometimes morphologically semi-cryptic. We group all ploidy levels in the A. bartramiana agamic complex and recognize as a species the diploid (A. bartramiana). The tetraploid is not given species status because it intergrades extensively with tetraploid congeners, as exemplified by the nothospecies named here, A. ×neglecta. Western North American A. cusickii is tetraploid, mostly distinct morphologically and ecologically, distinct genetically, and merits species status.
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Understanding diploid diversity: A first step in unraveling polyploid, apomictic complexity in Amelanchier
American journal of botany, 2015Co-Authors: Michael B. Burgess, Kevin R. Cushman, Eric T. Doucette, Christopher T. Frye, Christopher S CampbellAbstract:PREMISE OF THE STUDY Delimitation of Amelanchier species is difficult because of polyploidy and gametophytic apomixis. A first step in unraveling this species problem is understanding the diversity of the diploids that contributed genomes to polyploid apomicts. This research helps clarify challenging species-delimitation problems attending polyploid, apomictic complexity. METHODS We sampled 431 diploid accessions from 13 species, of which 10 are North American and three are Old World. Quantitative morphological analyses tested the null hypothesis of no discrete groups. Using three to nine diploid accessions per species, we constructed phylogenies with DNA sequences from ETS, ITS, the second intron of LEAFY, and chloroplast regions rpoB-trnC, rpl16, trnD-trnT, and ycf6-psbM. KEY RESULTS Most Amelanchier diploid taxa are morphologically and ecogeographically distinct and genetically exclusive lineages. They rarely hybridize with one another. Nuclear and chloroplast DNA sequences almost completely resolve the Amelanchier phylogeny. The backbone is the mostly western North American clade A, eastern North American clade B, and Old World clade O. DNA sequences and morphology support clades A and O as sister taxa. Despite extensive paralogy, our LEAFY data are phylogenetically informative and identify a clade (T) of three arborescent taxa within clade B. CONCLUSIONS Amelanchier diploids differ strikingly from polyploid apomicts, in that hybridization among them is rare, and they form taxa that would qualify as species by most species concepts. Knowledge of diploid morphology, phylogeny, and ecogeography provides a foundation for understanding the evolutionary history of polyploid apomicts, their patterns of diversification, and their species status.
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effects of apomixis and polyploidy on diversification and geographic distribution in Amelanchier rosaceae
American Journal of Botany, 2014Co-Authors: Michael B. Burgess, Kevin R. Cushman, Eric T. Doucette, Christopher T. Frye, Nadia Talent, Christopher S CampbellAbstract:UNLABELLED • PREMISE OF THE STUDY Amelanchier polyploid apomicts differ from sexual diploids in their more complex diversification, greater species problems, and geographic distribution. To understand these differences, we investigated the occurrence of polyploidy and frequency of apomixis. This research helps clarify species delimitation in an evolutionarily complex genus.• METHODS We used flow cytometry to estimate genome size of 1355 plants. We estimated the frequency of apomixis from flow-cytometrically determined ploidy levels of embryo and endosperm and from a progeny study using RAPD markers. We explored relationships of triploids to other ploidy levels and of ploidy levels to latitude plus elevation.• KEY RESULTS Diploids (32% of sample) and tetraploids (62%) were widespread. Triploids (6%) mostly occurred in small numbers with diploids from two or more species or with diploids and tetraploids. Seeds from diploids were 2% apomictic, the first report of apomixis in Amelanchier diploids. Seeds from triploids were 75% apomictic. We documented potential triploid bridge and triploid block from unbalanced endosperm and low pollen viability. Seeds from tetraploids were 97% apomictic, and tetraploids often formed microspecies. We did not find strong evidence for geographical parthenogenesis in North American Amelanchier. Most currently recognized species contained multiple ploidy levels that were morphologically semicryptic.• CONCLUSIONS Documentation of numerous transitions from diploidy to polyploidy helps clarify diversification, geographic distribution, and the species problem in Amelanchier. Despite the infrequent occurrence of triploids, their retention of 25% sexuality and capacity for triploid bridge may be important steps between sexual diploids and predominantly apomictic tetraploids.
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quantitative morphology of the Amelanchier agamic complex rosaceae at a maine site
Systematic Botany, 1998Co-Authors: Alison C Dibble, Christopher S Campbell, Wesley A Wright, Craig W GreeneAbstract:We tested the power of quantitative morphology to distinguish Amelanchier taxa at a Maine site where most individuals come from polyploid agamospermous species and taxonomic boundaries are poten- tially obscured by hybridization. We sampled 92 individuals from seven species and one putative hybrid, 13 from a microspecies we call A. "rubra," and 15 that fit no published description (unknowns). We performed principal coordinates analysis on 20 quantitative and qualitative characters, six recognized taxa, and the unknowns. Three groups are suggested: 1) A. intermedia, A. laevis, A. "rubra," four A. stolonifera, and four unknowns; 2) A. nantucketensis and three A. stolonifera, and 3) A. canadensis and 11 unknowns. In the scat- terplot of the first two principal coordinates axes, the only two species that overlap are A. intermedia and A. laevis. Discriminant function analyses indicate that A. "rubra" could be a hybrid of A. laevis and either A. nan- tucketensis or A. stolonifera and do not support the hypothesis that A. intermedia is A. canadensis X laevis. The unknowns group with A. canadensis, A. laevis, or A. "rubra" and mostly do not appear to be F1s. Agamospermy and/or insufficient time for hybrids to establish after disturbance may explain the absence of an extensive hybrid swarm.
P Kolodziejczyk - One of the best experts on this subject based on the ideXlab platform.
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characterization of saskatoon berry Amelanchier alnifolia nutt seed oil
Journal of Agricultural and Food Chemistry, 2009Co-Authors: Anna M Bakowskabarczak, Andreas Schieber, P KolodziejczykAbstract:The seeds of 17 cultivars of Saskatoon berries ( Amelanchier alnifolia Nutt.) were evaluated for their seed mass, oil content, fatty acid and triacylglycerol (TAG) composition, tocopherol profile, and sterol content. The oil content of the seeds ranged from 9.4% (cv. 'Pasture') to 18.7% (cv. 'Thiessen'). The seed oils contained mainly linoleic acid in the range from 47.3% (cv. 'Success') to 60.1% (cv. 'Lee 3') and oleic acid in the range from 26.3% (cv. 'Lee 3') to 38.1% (cv. 'Success'). The total tocopherol content ranged from 1053 to 1754 mg/kg of oil. alpha-Tocopherol was the major vitamin E compound in all berry seed oils investigated, accounting for 87% of total tocopherols. The predominant sterols were beta-sitosterol, Delta(5)-avenasterol, and campesterol. The sterols content in seed oil ranged from 7357 mg/kg of oil (cv. 'Success') to 15771 mg/kg of oil (cv. 'Lee 3'). Thirteen triacylglycerols (TAG) were identified in seed oils, among which LLL, LLO, LOO, LLP, LOP (L, linoleoyl; O, oleoyl; P, palmitoyl) represented 88% of the total TAG. TAG composition suggests good oxidative stability of the Saskatoon berry seed oil, which could be suitable for food and industrial applications. Moreover, Saskatoon berry seed oil may serve as potential dietary source of tocopherols, sterols, and unsaturated fatty acids.
B.h.l. Kwok - One of the best experts on this subject based on the ideXlab platform.
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Dehydration Techniques Affect Phytochemical Contents and Free Radical Scavenging Activities of Saskatoon berries (Amelanchier alnifolia Nutt.)
Journal of Food Science, 2006Co-Authors: B.h.l. Kwok, Chun Hu, Timothy D. Durance, David D. KittsAbstract:ABSTRACT: Saskatoon berries (Amelanchier alnifolia Nutt., cv. Thiessen and Smoky) were dehydrated using freeze-drying (FD), vacuum microwave drying (VMD), air-drying (AD), and a combination of air-drying and vacuum microwave drying (CD) methods. All processed berries had significantly reduced (P < 0.05) total phenolics and anthocyanin contents in addition to reduced antioxidant activities, as compared with fresh frozen (FF) berries. FD berries rendered the highest amount (P < 0.05) of anthocyanin and antioxidant activities, followed by VMD berries. The CD dehydration resulted in intermediate results between VMD and AD. The substantial decrease in both total phenolics and anthocyanin content in berries was corresponded to significant (P < 0.05) losses in antioxidant capacities measure in different model systems.
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saskatoon berries Amelanchier alnifolia nutt scavenge free radicals and inhibit intracellular oxidation
Food Research International, 2005Co-Authors: B.h.l. Kwok, David D. KittsAbstract:Two cultivars (Thiessen and Smoky) of Saskatoon berries (Amelanchier alnifolia Nutt.) possess free radical scavenging activities in a concentration-dependent manner, whereas Thiessen presented higher (p < 0.05) activity compared to Smoky due to its relatively abundant anthocyanin content. Total anthocyanin content significantly corresponded to free radical scavenging activities (p < 0.05). Solvent fractionation revealed that the free radical scavenging components, i.e., anthocyanin, predominantly occurred in the ethyl acetate and n-butanol extracted fractions, suggesting that active components are more likely to occur in glycoside forms. HPLC further confirmed the existence of cyanidin-3-O-galactoside and cyanidin-3-O-glucoside as leading anthocyanins in the Saskatoon berries. Furthermore, Saskatoon berries extracts from both cultivars suppressed peroxy-radical induced intracellular oxidation in a concentration-dependent manner without affecting cell viability. The obtained results provided useful information for the future application of Saskatoon berries in the nutraceutical industry.