• Preventive Nutrition and Food Science
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• v.20 no.1
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• pp.78-81
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• 2015

1,4-Dihydroxy-2-naphthoic acid (DHNA) is a bifidogenic growth stimulator (BGS) and could be a functional food ingredient since bifidobacteria are beneficial for human health. For that reason, lactic acid bacteria producing DHNA have been screened. A lactic acid bacterium LP1 strain isolated from a natural cheese was confirmed to produce DHNA, analyzed by a HPLC method. The strain was identified as Lactobacillus casei by 16S rRNA gene sequence analysis. The cell-free supernatant of fermented whey produced by L. casei LP1 presented the BGS activity for three bifidobacterial strains such as Bifidobacterium longum subsp. infantis KCTC 3127, Bifidobacterium bifidum KCTC 3202, and Bifidobacterium breve KCTC 3220 which were human-originated. To the best of our knowledge, a L. casei strain which can produce DHNA was firstly identified in this study.

• Applied Chemistry for Engineering
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• v.10 no.6
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• pp.863-870
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• 1999

The catalytic performance of Co-Mn-Br system was performed in the 2,6-dimethylnaphthalene(DMN) oxidation at relatively mild reaction conditions such as $160^{\circ}C$ and $6kg/cm^2$. Experiments were conducted using a $2{\ell}$ batch reactor with varying the concentrations of catalysts. The reaction route of DMN oxidation was considered by measuring the concentration of intermediate species. As the intermediate species, 2-formyl-6-naphthoic acid, 2-methyl-6-naphthoic acid and 2-hydroxymethyl-6-methylnaphthalene are found. It was found that the yield of 2,6-naphthalene dicarboxylic acid(NDA) is largely dependent on the Co and Br concentrations. In addition, it was observed that color-b was closely related with Mn concentration in this experimental range. The burning loss of solvent could be reduced by controlling the concentration of Mn and Br. Addition of small amount of Ce and Cu compounds led to increase the NDA yields and decrease the burning amount of solvent.

• Preventive Nutrition and Food Science
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• v.17 no.1
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• pp.83-86
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• 2012

To support beneficial effects of makgeolli for human health, we investigated for the presence of 1,4-dihydroxy-2-naphthoic acid (DHNA), a bifidogenic growth stimulator (BGS), from commercial makgeolli products. Among eleven makgeolli products (A~K), four showed positive peaks for DHNA in high performance liquid chromatography analysis. Makgeolli product A in particular contained the highest concentration of DHNA (0.44 ppm), as confirmed by liquid chromatography-mass spectrometry. Furthermore, BGS activity of the makgeolli product A was higher than those of products in which DHNA was not detected. These results indicate that makgeolli can be a good source for DHNA and that DHNA-enriched makgeolli could be developed by modifying manufacturing procedures and controlling its microbiota.

• Journal of Food Hygiene and Safety
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• v.30 no.4
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• pp.372-375
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• 2015

A lactic acid bacterium LP2 strain, which was previously isolated from a natural cheese, was confirmed to produce 1,4-dihydroxy-2-naphthoic acid (DHNA), a bifidogenic growth factor. The strain was identified as Lactobacillus plantarum (99% identity) by a homology search of the 16S rRNA gene sequence and named Lactobacillus plantarum LP2. The culture supernatant of the strain presented an antimicrobial activity against Helicobacter pylori KCTC 12083, where the DHNA might have influenced on the activity.

• Bulletin of the Korean Chemical Society
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• v.26 no.4
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• pp.655-657
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• 2005

• Rapid Communication in Photoscience
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• v.2 no.1
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• pp.34-37
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• 2013

Two novel antenna complexes of $Eu^{III}$ with 1-naphthoic acid (NA) as primary ligand and two aromatic N-donor ligands namely N-hexyl-N-(pyridin-2-yl) pyridin-2-amine (1) and 4-((dipyridin-2-ylamino)methyl)benzoic acid (2) have been synthesized and characterized by various spectroscopic techniques. The room-temperature (298 K) photoluminescence spectrum of $Eu^{III}$ complexes composed of typical line like emissions, assigned to transitions between the first excited state $^5D_0$ to the $^7F_J$ (J = 0-4), resulting in red emission along with the residual emission from the 1-naphthoic acid moiety in the blue region. The determined CIE color coordinate value for the complex 2 is (x = 0.36, y = 0.34), which is in white region.

• Food Science of Animal Resources
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• v.35 no.6
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• pp.867-873
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• 2015

1,4-Dihydroxy-2-naphthoic acid (DHNA), a precursor of menaquinone (vitamin K2), has an effect on growth stimulation of bifidobacteria and prevention of osteoporosis, making it a promising functional food material. Therefore, we tried to clone the menB gene encoding DHNA synthase from Leuconostoc mesenteroides CJNU 0147. Based on the genome sequence of Leu. mesenteroides ATCC 8293 (GenBank accession no., CP000414), a primer set (Leu_menBfull_F and Leu_menBfull_R) was designed for the PCR amplification of menB gene of CJNU 0147. A DNA fragment (1,190 bp), including the menB gene, was amplified, cloned into pGEM-T Easy vector, and sequenced. The deduced amino acid sequence of MenB (DHNA synthase) protein of CJNU 0147 had a 98% similarity to the corresponding protein of ATCC 8293. The menB gene was subcloned into pCW4, a lactic acid bacteria - E. coli shuttle vector, and transferred to CJNU 0147. The transcription of menB gene of CJNU 0147 (pCW4::menB) was increased, when compared with those of CJNU 0147 (pCW4) and CJNU 0147 (−). The DHNA was produced from it at a detectable level, indicating that the cloned menB gene of CJNU 0147 encoded a DHNA synthase which is responsible for the production of DHNA, resulting in an increase of bifidogenic growth stimulation activity.

• Archives of Pharmacal Research
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• v.25 no.3
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• pp.240-249
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• 2002

Dibenzyl-g-butyrolactone and 1,2,3,4-tetrahydro-2-naphthoic acid $\gamma$-lactone (TNL) derivatives were synthesized and evaluated for cytotoxic activity against some cancer cell lines. It was found that TNL derivatives with a shorter distance between C-4 in ring A and C'-2 in ring C were more cytotoxic, while dibenzyl-${\gamma}$-butyrolactones with a longer one were nearly inactive. In TNL series, presence of 3,4-dioxy group in ring A and 2-methoxy group in ring C was essential for the enhancement of the activity.

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2179-2182
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• 2014

• Bulletin of the Korean Chemical Society
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• v.28 no.10
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• pp.1863-1866
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• 2007