Stereochemistry of Astaxanthin Biosynthesis in the Marine Harpacticoid Copepod Tigriopus Californicus

The harpacticoid copepod Tigriopus californicus has been recognized as a model organism for the study of marine pollutants. Furthermore, the nutritional profile of this copepod is of interest to the aquafeed industry. Part of this interest lies in the fact that Tigriopus produces astaxanthin, an essential carotenoid in salmonid aquaculture. Here, we study for the first time the stereochemistry of the astaxanthin produced by this copepod. We cultured T. californicus with different feeding sources and used chiral high-performance liquid chromatography with diode array detection (HPLC-DAD) to determine that T. californicus synthesizes pure 3S,3’S-astaxanthin. Using meso-zeaxanthin as feed, we found that the putative ketolase enzyme from T. californicus can work with β-rings with either 3R- or 3S-oriented hydroxyl groups. Despite this ability, experiments in the presence of hydroxylated and non-hydroxylated carotenoids suggest that T. californicus prefers to use the latter to produce 3S,3’S-astaxanthin. We suggest that the biochemical tools described in this work can be used to study the mechanistic aspects of the recently identified avian ketolase.

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ECDYSTEROIDS OF SILENE ITALICA: GLYCOSIDIC AND NONGLYCOSIDIC COMPONENTS AND HPLC-DAD-ESI-MS PROFILE

chemistry of plant raw material ◽

10.14258/jcprm.2019045109 ◽

2019 ◽

pp. 135-147

Author(s):

Daniil Nikolayevich Olennikov ◽

Nina Igorevna Kashchenko

Keyword(s):

High Performance ◽

Diode Array ◽

Ionization Mass ◽

Diode Array Detection ◽

Mass Spectrometry Detection ◽

Plant Weight ◽

Esi Ms ◽

Array Detection ◽

First Time ◽

Derivatives Of

Silene italica (L.) Pers. is a species of Caryophyllaceae family which introduced samples contain ecdysteroids that was previously shown (Meng et al., 2001). In this paper, the composition of ecdysteroids of wild-growing S. italica was shown. Using high performance chromatography with diode-array detection and electrospray ionization mass-spectrometry detection (HPLC-DAD-ESI-MS) twenty-two compounds assigned to the ecdysteroid group. The non-glycoside components of S. italica were included twelve compounds and integristerone A, 26-hydroxyintegristerone A, 22-deoxyintegristerone A, 2-deoxyintegristerone A, and 2-deoxypolypodine B were identified for the first time. Ten compounds were characterized as ecdysteroid monoglycosides containing hexose fragment as a carbohydrate part. Trer were derivatives of 20-hydroxyecdysone, polypodine B, ecdysone and 2-deoxypolypodine B. For the first time, the presence of 22-deoxyintegristerone A hexoside non-detected in plant objects was found. Comparative analysis of the ecdysteroids composition of S. italica and well studied species S. italica spp. nemoralis (Báthori et al., 2000, 2002, 2004; Pongrácz et al., 2003; Simon et al., 2002) indicates their proximity. Quantitative analysis of five ecdysteroid content in the organs of S. italica showed that they were unevenly distributed in the plant. The concentration of 20-hydroxyecdysone was 0.10–32.12 mg/g and the total ecdysteroids content was 0.10–40.92 mg/g of dry plant weight. In general, it should be noted that the ability to produce and accumulate ecdysteroids was also observed for the wild samples of S. italica, which cultural samples was noted as ecdysteroid concentrator.

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C-/O-GLYCOSYL FLAVONES OF SILENE ITALICA

chemistry of plant raw material ◽

10.14258/jcprm.2019035110 ◽

2019 ◽

pp. 119-127

Author(s):

Daniil Nikolayevich Olennikov ◽

Nina Igorevna Kashchenko ◽

Nadezhda Konstantinovna Chirikova

Keyword(s):

High Performance ◽

Diode Array ◽

Ionization Mass ◽

Mass Spectrometry Detection ◽

Chemical Research ◽

The Family ◽

Array Detection ◽

Genus Silene ◽

First Time

Chemical research of Silene genus focused on the study of terpene compounds including ecdysteroids and triterpenoids, to the detriment of other classes of compounds. One of these poorly estimated group of substances are flavonoids, namely C-/O-glycosyl flavones, widely represented within the family Caryophyllaceae. Early studies revealed the presence of some C-glycosyl flavones (Zemtsova, Dzhumyrko, 1976; Darmogray, 1977), but a detailed study of the flavonoids was not conducted. Application of high performance chromatography with diode-array detection and electrospray ionization mass-spectrometry detection (HPLC-DAD-ESI-MS) allowed to found 14 flavonoids, which are C-, O- and C,O-glycosyl flavones in the aerial part of S. italica of Georgia origin. Ten components were discovered in S. italica for first time. The identified C-glycosides included monoglycosides as isoorientin, isovitexin, isoscoparin (chrysoeryol-6-C-glucoside) and diglycosides as carlinoside (luteolin-6-C-glucoside-8-C-arabinoside), schaftoside (apigenin-6-C-glucoside-8-C-arabinoside), isoschaftoside (luteolin-6-C-arabinoside-8-C-glucoside) and genkwanin-6-C-glucoside-8-C-arabinoside. Two O-glycosides, cosmosiin and cynaroside, and mixed C,O-glycosides as saponarin, isovitexin-2′′-O-arabinoside, isovitexin-6′′-O-arabinoside and O-hexosides od schaftosude and genkwanin-6-C-glucoside- 8-C-arabinoside were not previously identified in Silene genus. The known literature data (Mamadalieva et al., 2014) and the present data demonstrate the useful role of C-/O-glycosyl flavones in the systematics of the genus Silene.

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Three novel species and a new record of Daldinia (Hypoxylaceae) from Thailand

Mycological Progress ◽

10.1007/s11557-020-01621-4 ◽

2020 ◽

Vol 19 (10) ◽

pp. 1113-1132

Author(s):

Sarunyou Wongkanoun ◽

Kevin Becker ◽

Kanthawut Boonmee ◽

Prasert Srikitikulchai ◽

Nattawut Boonyuen ◽

...

Keyword(s):

New Record ◽

High Performance ◽

Sequence Data ◽

Novel Species ◽

Morphological Characters ◽

Diode Array ◽

Metabolite Profiles ◽

Array Detection ◽

Phylogenetic Affinities ◽

First Time

Abstract In an investigation of stromatic Xylariales in Thailand, several specimens of Daldinia were discovered. Three novel species (D. flavogranulata, D. phadaengensis, and D. chiangdaoensis) were recognized from a molecular phylogeny based on concatenated ITS, LSU, RPB2, and TUB2 sequence data, combined with morphological characters and secondary metabolite profiles based on high performance liquid chromatography coupled to diode array detection and mass spectrometry (HPLC-MS). The major components detected were cytochalasins (in D. flavogranulata and D. chiangdaoensis) and daldinin type azaphilones (in D. phadaengensis). In addition, D. brachysperma, which had hitherto only been reported from America, was found for the first time in Asia. Its phylogenetic affinities were studied, confirming previous suspicions from morphological comparisons that the species is closely related to D. eschscholtzii and D. bambusicola, both common in Thailand. Daldinia flavogranulata, one of the new taxa, was found to be closely related to the same taxa. The other two novel species, D. phadaengensis and D. chiangdaoensis, share characters with D. korfii and D. kretzschmarioides, respectively.

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Similarity of Data from Bee Bread with the Same Taxa Collected in India and Romania

Molecules ◽

10.3390/molecules23102491 ◽

2018 ◽

Vol 23 (10) ◽

pp. 2491 ◽

Cited By ~ 14

Author(s):

Adriana Urcan ◽

Adriana Criste ◽

Daniel Dezmirean ◽

Rodica Mărgăoan ◽

André Caeiro ◽

...

Keyword(s):

High Performance ◽

Total Phenolics ◽

Diode Array ◽

Diode Array Detection ◽

Phenolic Profile ◽

Glucose Ratio ◽

Bee Bread ◽

Array Detection ◽

G Ratio ◽

First Time

Bee Bread samples from Romania and India were analysed by microscopy and High Performance Liquid Chromatography with Diode Array Detection (HPLC/DAD) and compared with pollen from the correspondent taxa. The quantification of sugars, fructose/glucose ratio, total phenolics and flavonoids was also carried out. From the results was possible to identify Brassica and Eucalyptus samples that present similar HPLC/DAD profiles with the respective ultraviolet (UV) identification of the main compounds as Kaempferol-3-O-glycosides and Hydrocinnamic acid derivatives. The Fructose/Glucose (F/G) ratio and the total amounts of phenolics and flavonoids was in line with the prevalence of the specie identified. These coincident fingerprints gave the identification of the samples, as was previously proposed for bee pollens. This paper relates for the first time the achievement on the taxon carried out previously only for bee pollens. It was reported for the first time that this phenolic profile remains unchanged in the case of floral pollen (hand collected), bee pollen and bee bread. Despite the biochemical transformation that occurs during the fermentation of bee bread, it seems that these phenolic compounds are not affected and remain unchanged. Also, variables such as soil and climate do not seem to influence these compounds for the kind of samples under study.

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