Kaempferol glycosides from the flowers of Alcea nudiflora

1970 ◽  
Vol 6 (5) ◽  
pp. 643-644
Author(s):  
Z. P. Pakudina ◽  
A. S. Sadykov ◽  
A. Zuparov

Molecules ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 494
Author(s):  
Susanne Neugart ◽  
Christiane Bumke-Vogt

Recently, there have been efforts to use ultraviolet-B radiation (UV-B) as a biotechnological tool in greenhouses. Leafy Brassica species are mainly considered for their ability to synthesize glucosinolates and are valued as baby salads. They also have a remarkable concentration of chemically diverse flavonoid glycosides. In this study, the effect of short-term UV-B radiation at the end of the production cycle was investigated without affecting plant growth. The aim was to verify which exposure and adaptation time was suitable and needs to be further investigated to use UV as a biotechnological tool in greenhouse production of Brassica species. It is possible to modify the flavonoid glycoside profile of leafy Brassica species by increasing compounds that appear to have potentially high antioxidant activity. Exemplarily, the present experiment shows that kaempferol glycosides may be preferred over quercetin glycosides in response to UV-B in Brassica rapa ssp. chinensis, for example, whereas other species appear to prefer quercetin glycosides over kaempferol glycosides, such as Brassica oleracea var. sabellica or Brassica carinata. However, the response to short-term UV-B treatment is species-specific and conclusions on exposure and adaptation time cannot be unified but must be drawn separately for each species.



2001 ◽  
Vol 56 (9-10) ◽  
pp. 745-754 ◽  
Author(s):  
Ken G Ryan ◽  
Ewald E Swinny ◽  
Chris Winefield ◽  
Kenneth R Markham

AbstractWild-type Arabidopsis L. leaves exposed to low ultraviolet-B (U V B ) conditions contained predominantly kaempferol glycosides, with low levels of quercetin glycosides. The flavonoid level doubled on treatment with UVB and an increase in the ratio of quercetin: kaempferol was observed. These results suggest that flavonols protect Arabidopsis plants from UVB damage, and indicate that the flavonoid 3’-hydroxylase (F3’H) enzyme, which converts dihydrokaempferol to dihydroquercetin, may play a crucial role. The tt7 mutant lacks this gene and, after treatment with sub-ambient UVB, contained kaempferol glycosides exclusively, to a level of total flavonols similar to that in wild-type Arabidopsis. Total flavonols after enhanced UVB treatment were higher in tt7 than in similarly treated wild-type plants, and only kaempferol glycosides were detected. Despite this high level, tt7 plants were less tolerant of UVB radiation than wild-type plants. These observations suggests that kaempferol is a less effective photoprotectant than quercetin. The chalcone isomerase (CHI) mutant (tt5) surprisingly did not accumulate naringenin chalcone, and this suggests that the mutation may not be restricted to the CHI gene alone. The concentration of hydroxycinnamic acid derivatives did not change with UVB treatment in most varieties indicating that their role in UV photoprotection may be subordinate to that of the flavonoids.



2006 ◽  
Vol 70 (1) ◽  
pp. 279-281 ◽  
Author(s):  
Takashi HASHIMOTO ◽  
Yuko UEDA ◽  
Naomi OI ◽  
Hiroyuki SAKAKIBARA ◽  
Chengyuan PIAO ◽  
...  


2021 ◽  
Author(s):  
Xiaobai Li ◽  
Jian Sun ◽  
Jingyong Jiang ◽  
Zhen Chen ◽  
Aaron Jackson

Abstract Rubus chingii, is a red-fruited species of Rubus native to China, which is a popular and nutritious fruit in China. However, change in flavonoid composition and content during fruit maturation is poorly understood. This study examined flavonoids and the genes/proteins during four fruit ripening phases using LC-MS/MS. As a result, six major kinds of anthocyanins were first identified in R. chingii, which primarily consisted of flavanol-anthocyanins, are new to Rubus. Apart from anthocyanins, concentrations of fruit flavonoids were much higher than most berries including raspberries, and it is this that contributes to their high phenolic concentrations and antioxidant capabilities. In contrast to other known raspberries, R. chingii had a decline in flavonoids during fruit maturation, which was due to down-regulation of genes/proteins involved in phenylpropanoid and flavonoid biosynthesis. Surprisingly, anthocyanin continuously decreased during fruit coloration. This suggests that anthocyanins are not responsible for the fruit’s reddish coloration. The biosynthesis of these flavanol-anthocyanins consumed two flavonoid units both produced through the same upstream pathway. Their presence indicates a reduction in the potential biosynthesis of anthocyanin production. Also, the constantly low expression of RcANS gene down-regulated overall anthocyanin biosynthesis. The lack of RcF3’5’H gene/protein hindered the production of delphinidin glycosides. Flavonoids primarily comprising of quercetin/kaempferol-glycosides were predominately located at fruit epidermal-hair and placentae. The profile and biosynthesis of R. chingii flavonoids are unique to Rubus. It could be used to broaden the genetic base of raspberry cultivars and to improve their fruit quality.



Molecules ◽  
2020 ◽  
Vol 25 (11) ◽  
pp. 2481
Author(s):  
Anita M. Sutedja ◽  
Emiko Yanase ◽  
Irmanida Batubara ◽  
Dedi Fardiaz ◽  
Hanifah N. Lioe

Although the intake of jack bean (Canavalia ensiformis (L.) DC.), an underutilized tropical legume, can potentially decrease the risk of several chronic diseases, not much effort has been directed at profiling the polyphenolics contained therein. Hence, this work aimed to identify and quantify the dominant jack bean polyphenolics, which are believed to have antioxidant and other bioactivities. Four major compounds were detected and identified as kaempferol glycosides with three or four glycoside units. Their structures were established based on UV-visible, 1D, 2D NMR, and HR-ESI-MS analyses. Specifically, kaempferol 3-O-α-l-rhamnopyranosyl (1→6)- β-d-glucopyranosyl (1→2)-β-d-galactopyranosyl-7-O-[3-O-o-anisoyl]-α-l-rhamnopyranoside was detected for the first time, while the other three compounds have already been described in plants other than jack bean. This new compound was found to have a higher α-glucosidase inhibition activity compared to acarbose.



2009 ◽  
Vol 4 (12) ◽  
pp. 1934578X0900401 ◽  
Author(s):  
Bogdan Janda ◽  
Anna Stochmal ◽  
Paula Montoro ◽  
Sonia Piacente ◽  
Wieslaw Oleszek

The nutritional quality of Persian clover (Trifolium resupinatum), an important pasture crop, depends not only on a high protein content but also on the occurrence of animal health and welfare promoting phytochemicals. Nine phenolic constituents present in the aerial parts of this species were isolated and their structures confirmed by NMR and ESI-MS analyses. The compounds included two chlorogenic acids, four quercetin and two kaempferol glycosides, as well as the isoflavone formononetin-7-glucoside. The concentration of isoflavone was low, not exceeding 1.2 mg/g of dry matter. The concentration of flavonols ranged between 5.9 and 11.8 mg/g, depending on the sampling dates, with the highest concentration occurring in the first cut. A similar trend in the concentration was found for chlorogenic acids, which ranged from 2 mg/g in summer to 7.3 mg/g in spring.



1987 ◽  
Vol 23 (3) ◽  
pp. 378-379
Author(s):  
M. S. Luk'yanchikov ◽  
N. N. Guzhva ◽  
D. M. Elisevich


2013 ◽  
Vol 8 (11) ◽  
pp. 1934578X1300801 ◽  
Author(s):  
Keisuke Sakaguchi ◽  
Junichi Kitajima ◽  
Tsukasa Iwashina

Three new acylated delphinidin glycosides, delphinidin 3- O-β-[(2″- trans-caffeoylglucopyranosyl)-(1→2)-(6″-succinylgalactopyranoside)]–7- O-β-glucopyranoside (1), delphinidin 3- O-β-[(2″- trans-caffeoylglucopyranosyl)-(1→2)-(6″- trans-caffeoyl-tartaroyl-malonylgalactopyranoside)]–7- O-β-glucopyranoside (2), and delphinidin 3- O-β-[(2″- trans-caffeoylglucopyranosyl)-(1→2)-(6″- trans-caffeoyl-tartaroyl-malonylgalactopyranoside)]–3′- O-β-glucuronopyranoside (3), were isolated from the violet and violet-blue sepals of Clematis cultivars ‘Jackmanii Superba’ and ‘Fujimusume’. The chemical structures of the isolated anthocyanins were determined by LC-MS, characterization of hydrolyzates, and UV, 1H and 13 C NMR spectroscopy. The visible absorption spectra of these anthocyanins were compared with those of fresh sepals and crude extracts in pH 5.1 buffer solution. In addition, the co-pigment effect with some kaempferol glycosides and caffeoylglucose was examined.



Plants ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 142 ◽  
Author(s):  
Chloé Placines ◽  
Viana Castañeda-Loaiza ◽  
Maria João Rodrigues ◽  
Catarina G. Pereira ◽  
Azzurra Stefanucci ◽  
...  

Cakile maritima Scop. (sea rocket) is an edible halophyte plant with several ethnomedicinal uses. This work reports the chemical profile and bioactivities of food grade extracts from sea rocket organs. Toxicity was determined on mammalian cells, and phenolic profiling and the quantitation of the main metabolites were made by high-performance liquid chromatography coupled to mass spectrometry (HPLC-MS). Enzymatic inhibition was determined towards acetyl- and butyrylcholinesterase (AChE, BuChE), α-glucosidase, α-amylase, and tyrosinase. Docking studies were performed to tyrosinase, on the major metabolites, and samples were tested for antioxidant properties. Extracts were not toxic, were constituted mainly by flavonoids, and some compounds (roseoside and oleuropein) are here described for the first time in the species. The aerial organs’ ethanol extract had relevant activity towards 2,2-diphenyl-1-picrylhydrazyl [DPPH, half maximal inhibitory concentration (IC50) = 0.59 mg/mL], and ferric-reducing activity power (FRAP, IC50 = 0.99 mg/mL). All samples were more active towards AChE than on BuChE. The ethanol fruits’ extract inhibited α-glucosidase [2.19 mmol of equivalent of acarbose (ACAE)/g]. Samples were active against tyrosinase, especially the aerial organs’ ethanol extracts [25.9 mg of equivalent of kojic acid (KAE)/g]. Quercetin and kaempferol glycosides fit well into the enzymatic pocket of tyrosinase. Our results suggest sea rocket as a candidate to be further explored as a source of bioactive products.



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