• 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.

• 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.

• 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.28 no.10
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• pp.1863-1866
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• 2007

• Bulletin of the Korean Chemical Society
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• v.22 no.8
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• pp.821-826
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• 2001

Solvent sublation has been studied for the separation and determination of trace Zn(Ⅱ) and Pb(Ⅱ) in water samples. A synergy producing method was utilized to improve the efficiency of extraction in the sublation using an ion-pair of metal-naphth oate {M-(Nph)3- } complexes and tetra-n-butylammonium (TBA+ ) ion. After the M-(Nph)3- complexes were formed by adding 1-naphthoic acid to the sample solution, tetra-n-butylammonium bromide was added in the solution to form the ion-pair. And sodium lauryl sulfate (SLS) was added to make the ion-pair hydrophobic. The ion-pairs of the metal complexes were floated and extracted into methylisobutyl ketone (MIBK) from the aqueous solution by bubbling with nitrogen gas in a flotation cell. Metal ions in MIBK solution were measured by graphite furnace-AAS. Experimental conditions were optimized as follow so. After the pH of a 1.0 L water sample was adjusted to 5.0, 6.0 mL of 0.1 M 1-HNph and 10 mL of 0.03 M TBA-bromide were added to the sample to form ion-pairs, and 2.0 mL of 0.2%(w/v) SLS was added to make the ion-pairs hydrophobic. The solution was bubbled with 30 mL/min N2 gas for 5 minutes in a flotation cell. Linear calibration curves were obtained for the determination of Zn(Ⅱ) and Pb(Ⅱ) in several water samples. Reproducible results of showing a relative standard deviation of < 10% and recoveries of 80-100% could be obtained.

• Journal of Microbiology
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• v.37 no.2
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• pp.73-79
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• 1999

Pseudomonas sp. NGK1, isolated by naphthalene enrichment culture technique, is capable of degrading anthracene as a sole source of carbon and energy. The organism degraded anthracene through the intermediate formation of 1,2-dihydroxyanthracene, 2-hydroxy-3-naphthoic acid, salicylate, and catechol. The intermediates were isolated and characterized by TLC, spectrophotometry, and HPLC analysis. The cell free extract of anthracene-grown cells showed activities of anthracene dioxygenase, 2-hydroxy-3-naphthylaldehyde dehydrogenae, 2-hydroxy-3-naphthoate hydroxylase, salicylate hydroxylase and catechol 2,3-dioxygenase. The formed catechol as a metabolite is degraded through meta-cleavage with the formation of ${\alpha}$-hydroxymuconic semi-aldehyde.

• Journal of Microbiology
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• v.37 no.4
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• pp.185-192
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• 1999

A phenanthrene-degrading bacterium was isolated from an oil-spilled intertidal sediment sample and identified as Sphingomonas sp. KH3-2. The strain degraded polycyclic aromatic compounds such naphthalene, fluorene, biphenyl, and dibenzothiophene. When strain KH3-2 was cultured for 28 days at 25C, a total of 500 ppm of phenanthrene was degrated with a concomitant production of biomass and Folin-Ciocalteau reactive aromatic intermediates. Analysis of intermediates during phenanthrene degradation using high-performance liquid chromatography and gas chromatography/mass spectrometry indicated that Sphingomonas sp. KH3-2 primarily degrades phenanthrene to 1-hydroxy-2-naphthoic acid (1H2NA) and further metabolizes 1H2NA through the degradation pathway of naphthalene.