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Peter Sporns - One of the best experts on this subject based on the ideXlab platform.
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identification and quantification of Flavonol glycosides in almond seedcoats using maldi tof ms
Journal of Agricultural and Food Chemistry, 2002Co-Authors: Suzanne Frisonnorrie, Peter SpornsAbstract:Interest in the molecular composition of almonds is growing, due to their popularity in a wide variety of food formulations. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a powerful new technique that can be used to rapidly identify and quantify possible bioactive compounds in these popular tree nuts. Four Flavonol glycosides were identified in almond seedcoats for the first time: isorhamnetin rutinoside, isorhamnetin glucoside, kaempferol rutinoside, and kaempferol glucoside. A MALDI-TOF MS methodology was developed using rutin (quercetin-3-rutinoside) as an internal standard to quantitatively determine each of the four Flavonol glycosides. Results of MALDI-TOF MS analysis were verified by high performance liquid chromatography.
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MALDI-TOF MS analysis of food Flavonol glycosides.
Journal of agricultural and food chemistry, 2000Co-Authors: Jian Wang And, Peter SpornsAbstract:Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a new technique that is having a great impact on food analysis. This study is the first to demonstrate the use of MALDI-TOF MS to identify Flavonol glycosides in food samples. 2‘,4‘,6‘-Trihydroxyacetophenone was chosen as the best matrix because it worked for crude sample extracts and ionized Flavonol glycosides in both positive and negative MALDI-TOF MS modes. In the positive mode, multiple ion forms were observed for Flavonol glycosides, including [M + H]+, [M + Na]+, [M + K]+, and [M − H + Na + K]+, with further fragmentation through loss of glycosidic residues. The negative mode for all Flavonol glycosides resulted in [M − H]- ion formation without detectable fragmentation. The multiple ions in the positive mode gave more information on individual Flavonol glycoside structures than the negative mode. Flavonol glycosides showed similar intensities or responses in the positive mode, while kaempferol glycosides...
Baoru Yang - One of the best experts on this subject based on the ideXlab platform.
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Flavonol glycosides in berries of two major subspecies of sea buckthorn hippophae rhamnoides l and influence of growth sites
Food Chemistry, 2016Co-Authors: Oskar Laaksonen, Jie Zheng, Wei Yang, Martin Trepanier, Heikki Kallio, Baoru YangAbstract:Flavonol glycosides of wild sea buckthorn (Hippophae rhamnoides ssp. sinensis) berries from China and cultivated berries (H. rhamnoides ssp. mongolica) from Finland and Canada were identified and quantified. Twenty-six Flavonol glycosides were found with isorhamnetin and quercetin as the major aglycones. The contents of Flavonol glycosides ranged 23-250 mg/100 g fresh berries and were significantly higher in the berries of ssp. sinensis than in those of ssp. mongolica. Among the cultivars of ssp. mongolica, the berries of 'Oranzhevaya' had the lowest (23 mg/100 g) content, and those of 'Prevoshodnaya' the highest content of Flavonol glycosides (80 mg/100 g). Within the ssp. mongolica, the samples from Kittila (Northern Finland) had higher levels of most Flavonol glycosides than those from Turku (Southern Finland) and Quebec. Among the ssp. sinensis berries of different growth sites, increasing trends were detected in the contents of most of the compounds as the altitude increased and as the latitude decreased. The wild berries (ssp. sinensis) from Sichuan had remarkably high contents and unique profiles of Flavonol glycosides.
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Flavonol glycosides in wild and cultivated berries of three major subspecies of hippophae rhamnoides and changes during harvesting period
Food Chemistry, 2009Co-Authors: Baoru Yang, Teemu Halttunen, Olli Raimo, Keith R Price, Heikki KallioAbstract:Abstract Flavonol glycosides are an important group of bioactive components of sea buckthorn ( Hippophae rhamnoides ). The content and profile of Flavonol glycosides of some major subspecies and most cultivars as well as the variation amongst the harvesting years and dates are largely unknown. This study investigated Flavonol glycosides in wild berries of two major subspecies H. rhamnoides ssp. rhamnoides and ssp. sinensis and berries of eight cultivars of ssp. rhamnoides and mongolica by reverse phase high performance liquid chromatography combined with diode array detection. The major Flavonol glycosides were isorhamnetin-3-O-glucoside-7-O-rhamnoside, isorhamnetin-3-O-rutinoside, isorhamnetin-3-O-glucoside, isorhamnetin-3-O-sophoroside-7-O-rhamnoside, quercetin-3-O-rutinoside, quercetin-3-O-glucoside and quecertin-3-O-sophoroside-7-O-rhamnoside. The total content of Flavonol glycosides fell in the range of 27–130 mg per 100 g fresh berries with considerable variation amongst the origins and the harvesting years. Compared with the berries of ssp. sinensis and ssp. mongolica , the berries of ssp. rhamnoides contained high levels of isorhamnetin-3-O-glucoside-7-O-rhamnoside and isorhamnetin-3-O-glucoside and lower levels of quercetin-3-O-rutinoside and quercetin-3-O-glucoside. In the wild berries of ssp. sinensis , the contents of Flavonol glycosides reached maxima around late September to early October and decreased thereafter, whereas a general decreasing trend was seen in the cultivated berries of ssp. rhamnoides from the end of August to the end of October.
Lothar W Kroh - One of the best experts on this subject based on the ideXlab platform.
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the effect of temperature and radiation on Flavonol aglycones and Flavonol glycosides of kale brassica oleracea var sabellica
Food Chemistry, 2012Co-Authors: Susanne Neugart, Lothar W Kroh, Hanspeter Klaring, Michaela Zietz, Monika Schreiner, Sascha Rohn, Angelika KrumbeinAbstract:a b s t r a c t The winter crop kale has a complex profile of different glycosylated and acylated Flavonol glycosides which may be affected by global warming. To the best of our knowledge, compound-climate relation- ships for Flavonol aglycones and Flavonol glycosides were established for the first time. The investigated 10 major Flavonol glycosides responded structure-dependent in the investigated temperature range between 0 and 12 °C and the photosynthetic active radiation range between 4 and 20 mol m y 2 d y 1 , e.g. the decrease in temperature led to an increase in sinapic acid monoacylated and diacylated quercetin gly- cosides, while the sinapic acid monoacylated kaempferol glycosides showed a maximum at 4.5 °C. Fur- thermore, the hydroxycinnamic acid residues and the different number of glucose moieties in the 7- O position affected the response of kaempferol triglucosides. Consequently, global warming would result in lower concentrations of antioxidant-relevant quercetin glycosides in winter crops, suggesting a pro- duction at e.g. higher altitudes due to lower temperature.
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structural investigations of Flavonol glycosides from sea buckthorn hippophae rhamnoides pomace by nmr spectroscopy and hplc esi ms n
Journal of Agricultural and Food Chemistry, 2004Co-Authors: Daniel Rosch, Angelika Krumbein, Clemens Mugge, Lothar W KrohAbstract:Four Flavonol glycosides were isolated from an extract of sea buckthorn pomace (Hippophae rhamnoides) by Sephadex LH-20 gel chromatography and semipreparative HPLC. Their structures were elucidated by hydrolysis studies, ESI-MS(n), UV, and (1)H and (13)C NMR spectroscopy. The occurrence of the major Flavonol glycoside kaempferol 3-O-beta-sophoroside-7-O-alpha-rhamnoside in sea buckthorn is described here for the first time. A further 21 Flavonol glycosides of Sephadex LH-20 fractions of sea buckthorn pomace were characterized by HPLC-DAD-ESI-MS. The characteristic MS-MS and MS(3) fragmentation pattern of Flavonol glycosides previously identified in sea buckthorn juice and of Flavonol glycosides identified by NMR spectroscopy gave valuable indications for their identification. The results demonstrate that loss of the sugar moiety from C-7 of the aglycon is more favored than fission of the glycosidic linkage at the C-3 position. Thus, most of the compounds identified were 7-rhamnosides of isorhamnetin, kaempferol, and quercetin, which exhibit different substitution patterns at the C-3 position, mainly glucosides, rutinosides, and sophorosides. In addition, numerous Flavonol glycosides were detected lacking a sugar moiety at C-7. Finally, eight Flavonol derivatives were identified that are acylated by hydroxybenzoic or hydoxycinnamic acids.
Heikki Kallio - One of the best experts on this subject based on the ideXlab platform.
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Flavonol glycosides in berries of two major subspecies of sea buckthorn hippophae rhamnoides l and influence of growth sites
Food Chemistry, 2016Co-Authors: Oskar Laaksonen, Jie Zheng, Wei Yang, Martin Trepanier, Heikki Kallio, Baoru YangAbstract:Flavonol glycosides of wild sea buckthorn (Hippophae rhamnoides ssp. sinensis) berries from China and cultivated berries (H. rhamnoides ssp. mongolica) from Finland and Canada were identified and quantified. Twenty-six Flavonol glycosides were found with isorhamnetin and quercetin as the major aglycones. The contents of Flavonol glycosides ranged 23-250 mg/100 g fresh berries and were significantly higher in the berries of ssp. sinensis than in those of ssp. mongolica. Among the cultivars of ssp. mongolica, the berries of 'Oranzhevaya' had the lowest (23 mg/100 g) content, and those of 'Prevoshodnaya' the highest content of Flavonol glycosides (80 mg/100 g). Within the ssp. mongolica, the samples from Kittila (Northern Finland) had higher levels of most Flavonol glycosides than those from Turku (Southern Finland) and Quebec. Among the ssp. sinensis berries of different growth sites, increasing trends were detected in the contents of most of the compounds as the altitude increased and as the latitude decreased. The wild berries (ssp. sinensis) from Sichuan had remarkably high contents and unique profiles of Flavonol glycosides.
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Flavonol glycosides in wild and cultivated berries of three major subspecies of hippophae rhamnoides and changes during harvesting period
Food Chemistry, 2009Co-Authors: Baoru Yang, Teemu Halttunen, Olli Raimo, Keith R Price, Heikki KallioAbstract:Abstract Flavonol glycosides are an important group of bioactive components of sea buckthorn ( Hippophae rhamnoides ). The content and profile of Flavonol glycosides of some major subspecies and most cultivars as well as the variation amongst the harvesting years and dates are largely unknown. This study investigated Flavonol glycosides in wild berries of two major subspecies H. rhamnoides ssp. rhamnoides and ssp. sinensis and berries of eight cultivars of ssp. rhamnoides and mongolica by reverse phase high performance liquid chromatography combined with diode array detection. The major Flavonol glycosides were isorhamnetin-3-O-glucoside-7-O-rhamnoside, isorhamnetin-3-O-rutinoside, isorhamnetin-3-O-glucoside, isorhamnetin-3-O-sophoroside-7-O-rhamnoside, quercetin-3-O-rutinoside, quercetin-3-O-glucoside and quecertin-3-O-sophoroside-7-O-rhamnoside. The total content of Flavonol glycosides fell in the range of 27–130 mg per 100 g fresh berries with considerable variation amongst the origins and the harvesting years. Compared with the berries of ssp. sinensis and ssp. mongolica , the berries of ssp. rhamnoides contained high levels of isorhamnetin-3-O-glucoside-7-O-rhamnoside and isorhamnetin-3-O-glucoside and lower levels of quercetin-3-O-rutinoside and quercetin-3-O-glucoside. In the wild berries of ssp. sinensis , the contents of Flavonol glycosides reached maxima around late September to early October and decreased thereafter, whereas a general decreasing trend was seen in the cultivated berries of ssp. rhamnoides from the end of August to the end of October.
Suzanne Frisonnorrie - One of the best experts on this subject based on the ideXlab platform.
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identification and quantification of Flavonol glycosides in almond seedcoats using maldi tof ms
Journal of Agricultural and Food Chemistry, 2002Co-Authors: Suzanne Frisonnorrie, Peter SpornsAbstract:Interest in the molecular composition of almonds is growing, due to their popularity in a wide variety of food formulations. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a powerful new technique that can be used to rapidly identify and quantify possible bioactive compounds in these popular tree nuts. Four Flavonol glycosides were identified in almond seedcoats for the first time: isorhamnetin rutinoside, isorhamnetin glucoside, kaempferol rutinoside, and kaempferol glucoside. A MALDI-TOF MS methodology was developed using rutin (quercetin-3-rutinoside) as an internal standard to quantitatively determine each of the four Flavonol glycosides. Results of MALDI-TOF MS analysis were verified by high performance liquid chromatography.