• Journal of Plant Biotechnology
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• v.33 no.2
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• pp.85-91
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• 2006

Flavanone 3$\beta$-hydroxylase (FHT) is an enzyme acting in the central part of the flavonoid biosynthesis pathway. FHT catalyses the hydroxylation of flavanone to dihydroflavonols in the anthocyanin pathway. In this paper we describe the cloning and expression of the genes encoding the flavonoid-biosynthetic enzyme FHT in Gypsophila paniculata L. A heterologous cDHA probe from Dianthus cavophyllus was used to isolate FHT-encoding cDHA clones from Gypsophila paniculata L.. Inspection of the 1471 bp long sequence revealed an open reading frame 1047 bp, including a 190 bp 5' leader region and 288 bp 3' untranslated region. Comparison of the coding region of this FHT cDHA sequence including the sequences of Arabidopsis thaliana, Citrus sinensis, Dianthus caryophyllus, Ipomoea batatas, Matthiola incana, Nierembergia sp, Petunia hybrida, Solanum tuberosum, Vitis vinifera reveals a identity higher than 69% at the nucleotide level. The function of this nucleotide sequences were verified by comparison with amino acid sequences of the amino-terminus and tryptic peptides from purified plant enzyme, by northern blotting with mRHA from wild type and mutant plants, by in vitro expression yielding and enzymatically active hydroxylase, as indicated by the small dihydrokaempferol peak. Genomic southern blot analysis showed the presence of only one gene for FHT in Gypsophila paniculata.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2528-2530
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• 2013

• BMB Reports
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• v.40 no.6
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• pp.870-874
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• 2007

We cloned a uridine-diphosphate dependent glycosyl-transferase RUGT-10 from Oryza sativa. The recombinant enzyme was expressed by glutathione-S transferase gene fusion system in Escherichia coli. RUGT10 showed different regioselectivity depending on the structures of substrates (e.g. flavanone, flavonol, and flavone). Apparently, flavanone such as naringenin and eriodictyol gave one 7-O-glucoside while flavone and flavonol gave more than two products with preferential glucosylation position of hydroxyl group at C-3 position.

• Archives of Pharmacal Research
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• v.29 no.5
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• pp.343-347
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• 2006

A new flavanone Persinol (1) and the new flavanone glucosides persinosides A (2) and B (3), along with known flavonoids (4 and 5) have been isolated from the ethyl acetate soluble fraction of the whole plants of Aerva persica. Their structures were elucidated on the basis of extensive analysis of nuclear magnetic resonance (1D & 2D-NMR) spectral data. All of them showed profound antioxidative activities by DPPH and cytochrome-c-reduction assays using the HL-60 cell culture system.

• Journal of Korean Society of Forest Science
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• v.86 no.3
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• pp.378-390
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• 1997

Ten total populations of Korean fir (Abies koreana Wilson) and Manshurian fir [A. nephrolepis (Traut.) Maxim.] were sampled from south Korea to investigate patterns of intraspecific variation in these species and to evaluate a recognition of the two species. Principal components analysis and cluster analysis were performed both on seed-cone data and on needle morphology data. The characters that contributed most to the separation between A. koreana and A. nephrolepis along three principal components axis were leaf width, length of seed, width of seed wing, length of seed wing, cone width, width of scale, and length of bract tip, but these characters were not diagnostic because of overlap in reality. Therefore, all these characters were not reliable in distinguishing these two taxa including bract position (exerted and recurved vs. exerted and straight). The individuals of A. koreana from Mt. Chi-ri appeared quite unique probably on account of its larger cone size and longer scale tip, while those from Mt. Hal-la of A. koreana were generally distinct from others in terms of their larger seed and seed wing and longer scale width. The Mt. Duk-yu specimens of A. korecana appeared somewhat smaller but more data were needed due to the small sampling size. Generally, the gradual clinal geographic trends made evident by the position of resin ducts in leaves of A. koreana can be detected. The southern populations, Mt. Hal-la (an insular population) were generally distinct from the northern populations (Mt. Chi-ri, Mt. Ga-ya and Mt. Duk-yu) in terms of their position of resin duct (medial, within mesophyll vs marginal, close to epidermis : 100% vs 75 or 50%). Although no sharp boundary separating these two species could be detected based on cone and needle morphology, the observed clinal pattern was distinct in northern populations of A. koreana and southern population of A. nephrnlepis. In a preceding study of the flavonoids variation of 20 species in eastern Asia, flavanone (5-deoxyflavanone) was found to be characteristic of A. faxoniana Rehder et Wilson, A. georgei Orr of China and A. koreana of Korea. A. faxoniana, which is assumed to be primitive species, has position of resin duct relative to both the medial and the marginal, while A. georgei and A. koreana are identified by marginal position of resin duct. With respect of foliar flavonoids chemistry, A. koreana was distinct from A. nephrolepis : the southmost samples (Mt. Hal-la and Mt. Chi-ri) contained additional flavonoids derivatives (mainly flavanone) that were not found in the northmost samples of A. nephrolepis except a few individuals from Mts. Seo-rak and Tae-bak populations of Kwang-won province. The presence of A. koreana type flavonoids in two Chinese species suggested that position of resin duct may be a phyletic character. Abies koreana including two Chinese taxa, exhibited the most elaborate and specialized flavonoids profile within the Abies in eastern Asia. Contrary to our initial expectations, the apparent intermediates between A. nephrolepis and A. koreana in Duk-yu and Ga-ya mountains were found. The pattern of variation on position of resin duct and flavonoids chemistry in these populations of A. kareana suggested that genetic interchange or natural hybridization had occurred between these two species. The evidence needed to resolve the status of this taxon is still inconclusive in our opinion until intermediate individuals from Mts. Duk-yu and Ga-ya show indication of hybridization between the two species.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.975-975
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• 2005

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2002.04b
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• pp.162-162
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• 2002

• Bulletin of the Korean Chemical Society
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• v.22 no.1
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• pp.97-99
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• 2001

• Journal of Radiation Industry
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• v.2 no.3
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• pp.121-128
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• 2008

Flavanone-3-hydroxylase (F3H) is one of the key enzymes for the biosynthesis of flavonals, anthocyanins, catechins and proanthocyanins. F3H catalyzes the $3{\beta}$-hydroxylation of (2S)-flavonones to form (2R, 3R)-dihydroflavonols. In this report, we isolated a full-length cDNA of RocF3H from black raspberry (Rubus occidentalis L.) using a reverse transcriptase-PCR and rapid amplification of the cDNA ends (RACE)-PCR. The full-length cDNA of RocF3H contains a 1,098 bp open reading frame (ORF) encoding a 365 amino acid protein with a calculated molecular weight of about 41.1 kDa and isoelectric point (pI) of 5.45. The genomic DNA analysis revealed that the RocF3H gene had three exons and two introns. Comparison of the deduced amino acid sequence of the RocF3H with other F3Hs revealed that the protein is highly homologous with various plant species. The conserved amino acids ligating the ferrous iron and the residues participating in the 2-oxoglutarate binding (R-X-S) were found in RocF3H at the similar positions to other F3Hs. Southern blot analysis indicated that RocF3H exist a multi-gene family. The isolation of RocF3H gene will be helpful to further study the role of F3H gene in the biosynthesis of flavonoids in R. occidnetalis.

• Korean Journal of Pharmacognosy
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• v.40 no.4
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• pp.370-375
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• 2009

Overproduction of peroxynitrite ($ONOO^-$) causes a variety of disease such as atherosclerosis, hypercholesterolemia, diabetes mellitus or obesity. Peroxynitrite scavenging activities and HPLC analysis on the five Oriental medicinal drugs belonging to the genus Citrus, Aurantium or Poncirus (Rutaceae family) and HPLC analysis were taken to evaluate flavanone glycosides with peroxynitrite scavenging activity. The $IC_{50}s$ of the five crude drugs were shown as follows: Aurantii nobilis Pericarpium (Jinpi, 18.3 ${\mu}g$/ml), Citrii unshiu Pericarpium (Chungpi, 7.50${\mu}g$/ml), Citrii unshiu Semen (Gyulhaek, >50.0${\mu}g$/ml), Aurantii Fructus (Jigak, 18.3${\mu}g$/ml), and Poncirii Fructus (Jisil, >50.0${\mu}g$/ml) where Korean crude drug's names are noted in the parenthesis. Peroxynitrite scavenging effect of flavanones or their glycosides usually contained in Citrus species were observed as follows: hesperetin (1.89 ${\mu}g$/ml), naringenin (7.77 ${\mu}g$/ml), hesperidin (8.44 ${\mu}g$/ml), poncirin (>50.0 ${\mu}g$/ml)and ponciretin(>50.0 ${\mu}g$/ml). The activities of naringin and poncirin with ${\alpha}$-L-rhamnopyranosyl($1{\rightarrow}2$)-${\beta}$-D-glucopyranosyl moiety were weak. HPLC analytical data revealed that Jinpi (the peels of mature fruits of Citrus unshiu) and Chungpi (the peels of immature fruits of C. unshiu) had high quantities of hesperidin as the value of 142.1${\pm}$0.21 and 104.51${\pm}$1.10 mg/g dried weight, respectively. Poncirin was clearly detected in only Jisil and naringenin and naringin were not observed on the HPLC chromatogram of the five crude drugs.