Karotinoidok és karotinoid-izomerek növénybiokémiai jelentősége = Significance of carotenoids and carotenoid-isomers in plant biochemistry

A karotinoidokból és karotinoid-izomerekből különböző kísérleti körülmények között történt besugárzás (? > 350 nm) hatására képződő karotinoid-gyökök, gyök-kationok (Car•, Car•+) és gyök-anionok (Car•?) tulajdonságait ENDOR- és HYSCORE-spektroszkópiával, valamint különböző tömegspektrometriai módszerekkel vizsgálva értékes adatokat nyertünk a karotinoidok fotoszintézisben betöltött szerepére. Vizsgáltuk különböző növényekből, növényi részekből nyert fitoxantin-keverékek Helicobacter pylori elleni, citotoxikus, multidrog-rezisztencia-gátló és szabadgyök-fogó (scavanger) hatását; két fontos paprika-karotinoid (kapszantin, kapszorubin) és különböző karbonsavakkal képzett észtereik antikarcinogén hatását. Vizsgáltuk a karotinoidoknak a lipid kettősrétegek biofizikai tulajdonságaira gyakorolt hatását. Tanulmányoztuk egy új, (9Z)-karotinoid-5,6-epoxidokat hasító enzim aktivitását. Elvégeztük az enzim 4 génjének klónozását és funkcionális jellemzését. Vizsgáltuk két őszibarack-fajta karotinoid-tartalmának változását a gyümölcsök érése során. Vizsgáltuk a lutein, a likopin és a ?-karotin ciklodextrinekkel képzett vízoldható zárvány-komplexeinek gyulladáscsökkentő hatását in vitro állatkísérleti modellekben. Kromatográfiás módszerekkel (CC, HPLC) meghatároztuk számos gyógynövény virágzatának és termésének pontos karotinoid-összetételét; izoláltuk a fő komponenseket, igazoltuk szerkezetüket. | Valuable data were gained about the role of carotenoids in photosynthesis by examining the features of carotenoid radicals, radical cations (Car•, Car•+) and radical anions (Car•?), which were formed from carotenoids and carotenoid isomers on the effect of irradiation (? > 350 nm) under various experimental conditions, with ENDOR- and HYSCORE-spectroscopy, as well as different mass spectrometry techniques. The activity of phytoxanthin mixtures obtained from different plants was tested against Helicobacter pylori, and their cytotoxic, multidrug-resistance-inhibitory and scavenger effect was investigated, as well as the anticarcinogenic effect of two paprika carotenoids (capsanthin, capsorubin) and their esters formed with various carboxylic acids. The effect of carotenoids on the biophysical properties of lipid double layers was evaluated as well. The activity of a new enzyme cleaving (9Z)-carotenoid-5,6-epoxids was investigated. Four genes of the enzyme were cloned and their functional analysis was provided. The carotenoid content of two peach cultivars was monitored throughout the ripening process of the fruits. The anti-inflammatory effect of water-soluble lutein-, lycopene- and ?-carotene-cylclodextrine complexes was investigated in in vitro animal models. The exact carotenoid composition of the inflorescence and fruit was determined in several medicinal plants with chromatographic techniques (CC, HPLC); the main components were isolated and their structure was verified

Study of 'Redhaven' peach and its white-fleshed mutant suggests a key role of CCD4 carotenoid dioxygenase in carotenoid and norisoprenoid volatile metabolism

<p>Abstract</p> <p>Background</p> <p>Carotenoids are plant metabolites which are not only essential in photosynthesis but also important quality factors in determining the pigmentation and aroma of flowers and fruits. To investigate the regulation of carotenoid metabolism, as related to norisoprenoids and other volatile compounds in peach (<it>Prunus persica </it>L. Batsch.), and the role of carotenoid dioxygenases in determining differences in flesh color phenotype and volatile composition, the expression patterns of relevant carotenoid genes and metabolites were studied during fruit development along with volatile compound content. Two contrasted cultivars, the yellow-fleshed 'Redhaven' (RH) and its white-fleshed mutant 'Redhaven Bianca' (RHB) were examined.</p> <p>Results</p> <p>The two genotypes displayed marked differences in the accumulation of carotenoid pigments in mesocarp tissues. Lower carotenoid levels and higher levels of norisoprenoid volatiles were observed in RHB, which might be explained by differential activity of carotenoid cleavage dioxygenase (CCD) enzymes. In fact, the <it>ccd4 </it>transcript levels were dramatically higher at late ripening stages in RHB with respect to RH. The two genotypes also showed differences in the expression patterns of several carotenoid and isoprenoid transcripts, compatible with a feed-back regulation of these transcripts. Abamine SG - an inhibitor of CCD enzymes - decreased the levels of both isoprenoid and non-isoprenoid volatiles in RHB fruits, indicating a complex regulation of volatile production.</p> <p>Conclusions</p> <p>Differential expression of <it>ccd4 </it>is likely to be the major determinant in the accumulation of carotenoids and carotenoid-derived volatiles in peach fruit flesh. More in general, dioxygenases appear to be key factors controlling volatile composition in peach fruit, since abamine SG-treated 'Redhaven Bianca' fruits had strongly reduced levels of norisoprenoids and other volatile classes. Comparative functional studies of peach carotenoid cleavage enzymes are required to fully elucidate their role in peach fruit pigmentation and aroma.</p

Cryptocapsinepoxide-type Carotenoids from Red Mamey, Pouteria sapota

Three new carotenoids, cryptocapsin-5,6-epoxide, 3ʹ-deoxycapsanthin-5,6-epoxide, and cryptocapsin-5,8-epoxides, have been isolated from the ripe fruits of red mamey (Pouteria sapota). Cryptocapsin-5,6-epoxide was prepared by partial synthesis via epoxidation of cryptocapsin and the (5R,6S)- and (5S,6R)-stereoisomers were identified by HPLC-ECD analysis. Spectroscopic data of the natural (anti) and semisynthetic (syn) derivatives obtained by acid-catalyzed rearrangement of cryptocapsin-5,8-epoxide stereoisomers were compared for structural elucidation. Chiral HPLC separation of natural and semisynthetic samples of cryptocapsin-5,8-epoxides was performed and HPLC-ECD analysis allowed configurational assignment of the separated stereoisomers

Study on the elution order of carotenoids on endcapped C18 and C30 reverse silica stationary phases. A review of the database

We provide a database which presents the separation characteristics of C18 and C30 stationary phases using carotenoids with diverse structures, including isomers, from the apolar carotenes to the very polar tetrahydroxy xantophylls. The retention behavior of more than 90 carotenoids on a C18 and C30 stationary phase were studied. The influence of structural differences of the carotenoids on the elution order for the two columns is discussed. Octadecyl bonded silica phase produces good separation for the whole polarity range of carotenoids. On this phase carotenoids are eluted in the order of their polarity. The examined polar compounds, including optical isomers, could be well separated on a C18 phase. However, the separation of regio- and geometrical isomers of carotenoids, as well as non-polar carotenes, is better achieved using a C30 phase

Isolation and Analysis of Carotenoids in Hungary from Zechmeister until Today

L&aacute;szl&oacute; Zechmeister, one of the most important pioneers of carotenoid chemistry, died 50 years ago. He founded a carotenoid research group in P&eacute;cs (Hungary), which is the only place in the world where carotenoid research has been conducted continuously over the past 95 years. This review presents the life of Zechmeister and gives a summary about the evolution of the methods of analysis, isolation, and structure elucidation of carotenoids from the 1930s until today, based on the results of the research group founded by Zechmeister

Carotenoid Composition of the Fruit of Red Mamey (Pouteria sapota)

The detailed carotenoid analysis of red mamey (Pouteria sapota) was achieved by HPLC-DAD-MS, chemical tests, and cochromatography with authentic samples. Altogether 47 components were detected and 34 identified from the total extract or after fractionation with column chromatography. The main carotenoids were cryptocapsin, sapotexanthin, and capsanthin 5,6-epoxide. Some further minor components containing the κ-end group with or without a hydroxy group and their 5,6-epoxy precursors were identified. Some comments are made about the biosynthesis of κ-carotenoids in red mamey

Carotenoid composition and in vitro pharmacological activity of rose hips

The aim of the present study was to compare carotenoid extracts of Rose hips (Rosa canina L.) with regard to their phytochemical profiles and their in vitro anti-Helicobacter pylori (H. pylori), cytotoxic, multidrug resistance (MDR) reversal and radical scavenging activity. Carotenoid composition was investigated in the different fractionation of rose hips, using extraction methods. Six main carotenoids - epimers of neochrome, lutein, zeaxanthin, rubixanthin, lycopene, β,β-carotene - were identified from Rose hips by their chromatographic behavior and UV-visible spectra, which is in accordance with other studies on carotenoids in this plant material. The active principles in the carotenoid extract might differ, depending upon the extraction procedures.on-line at: www.actabp.pl (Open Access Journal

Lutein Isomers: Preparation, Separation, Structure Elucidation, and Occurrence in 20 Medicinal Plants

Lutein and its cis-isomers occur in a lot of plants, including a variety of flowers. In this study, lutein isomers were produced via iodine-catalyzed isomerization, and four cis-isomers (9Z-, 9′Z-, 13Z-, and 13Z′) were isolated by means of column chromatography and semipreparative HPLC. The structures of the 9′Z- and 13′Z-isomers were elucidated via NMR measurements. These compounds were used as standards for the HPLC-DAD-MS determination of the carotenoid composition of the flowers of 20 plant species, in which lutein and its geometrical isomers are the main components. The flowers showed great variation in their cis- and trans-lutein content, and also in the presence or absence of other carotenoids, such as violaxanthin, neoxanthin, β-cryptoxanthin, and β-carotene. Some of the investigated flowers were found to be rich sources of lutein without zeaxanthin

Isolation of β-Cryptoxanthin-epoxides, Precursors of Cryptocapsin and 3·-Deoxycapsanthin, from Red Mamey (Pouteria sapota)

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