Jae Hak Sohn

Wonkwang University, Riri, North Jeolla, South Korea

Are you Jae Hak Sohn?

Claim your profile

Publications (38)60.11 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The new tanzawaic acid derivative, 2E,4Z-tanzawaic acid D (I), is isolated along with four known analogues from the marine-derived fungus Penicillium sp.
    ChemInform 05/2015; 46(19). DOI:10.1002/chin.201519277
  • [Show abstract] [Hide abstract]
    ABSTRACT: Chemical investigation of a marine-derived fungus Penicillium sp. SF-6013 resulted in the discovery of a new tanzawaic acid derivative, 2E,4Z-tanzawaic acid D (1), together with four known analogues, tanzawaic acids A (2) and D (3), a salt form of tanzawaic acid E (4), and tanzawaic acid B (5). Their structures were mainly determined by analysis of NMR and MS data, along with chemical methods. Preliminary screening for anti-inflammatory effects in lipopolysaccharide (LPS)-activated microglial BV-2 cells showed that compounds 1, 2, and 5 inhibited the production of nitric oxide (NO) with IC50 values of 37.8, 7.1, and 42.5μM, respectively. Compound 2 also inhibited NO production in LPS-stimulated RAW264.7 murine macrophages with an IC50 value of 27.0μM. Moreover, these inhibitory effects correlated with the suppressive effect of compound 2 on inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression in LPS-stimulated RAW264.7 and BV2 cells. In addition, compounds 2 and 5 significantly inhibited the activity of protein tyrosine phosphatase 1B (PTP1B) with the same IC50 value (8.2μM). Copyright © 2014 Elsevier Ltd. All rights reserved.
    Bioorganic & Medicinal Chemistry Letters 12/2014; 24(24). DOI:10.1016/j.bmcl.2014.10.035 · 2.33 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Constipation is a common problem in males and females. The aim of the present study was to evaluate the laxative effects of fermented rice extract (FRe) on rats with loperamide-induced constipation. FRe (100, 200 and 300 mg/kg) was administered orally once per day for six days following 1 h loperamide treatment. The laxative effects of FRe were compared with those of sodium picosulfate (S. picosulfate). Following the induction of constipation in the rats, a marked decrease was observed in the fecal pellet number and water content discharged over 24 h, the surface mucus thickness in the colonic lumen, intestinal charcoal transit ratio, thickness of the colonic mucosa and the number of mucus-producing cells, while an increase was observed in the number of fecal pellets remaining in the colonic lumen and their mean diameter, as compared with the normal vehicle control rats. These conditions were significantly alleviated following the administration of the three doses of FRe when compared with the loperamide control group. However, the alleviating effects were lower than those of S. picosulfate, with the exception of the intestinal charcoal transit ratio. Similar effects on the intestinal charcoal transit ratio were detected for the three doses of FRe when compared with the S. picosulfate-treated rats. In conclusion, the results indicated that FRe exhibits a laxative effect without causing diarrhea, as compared with sodium picosulfate; thus, FRe may be effective as a complementary medicine in patients suffering from lifestyle-induced constipation.
    Experimental and therapeutic medicine 12/2014; 8(6):1847-1854. DOI:10.3892/etm.2014.2030 · 0.94 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In the course of a search for anti-neuroinflammatory metabolites from marine fungi, aurantiamide acetate (1) was isolated from marine-derived Aspergillus sp. as an anti-neuroinflammatory component. Compound 1 dose-dependently inhibited the production of nitric oxide (NO) and prostaglandin E2 (PGE2) in BV2 microglial cells. It also attenuated inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), and other pro-inflammatory cytokines, such as interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α). In a further study designed to elucidate the mechanism of its anti-neuroinflammatory effect, compound 1 was shown to block the activation of nuclear factor-kappa B (NF-κB) in lipopolysaccharide (LPS)-induced BV2 microglial cells by inhibiting the phosphorylation of the inhibitor kappa B-α (IκB)-α. In addition, compound 1 decreased the phosphorylation levels of c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinases (MAPKs). These results suggest that compound 1 has an anti-neuroinflammatory effect on LPS stimulation through its inhibition of the NF-κB, JNK and p38 pathways. Copyright © 2014 Elsevier B.V. All rights reserved.
    International Immunopharmacology 12/2014; 23(2):568-74. DOI:10.1016/j.intimp.2014.10.006 · 2.71 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Two benzaldehyde derivatives, flavoglaucin (1) and isotetrahydro-auroglaucin (2), were isolated from the marine fungus Eurotium sp. SF-5989 through bioassay- and 1H NMR-guided investigation. In this study, we evaluated the anti-inflammatory effects of these compounds in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. We demonstrated that compounds 1 and 2 markedly inhibited LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production by suppressing inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression without affecting cell viability. We also demonstrated that the compounds reduced the secretion of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). Furthermore, compounds 1 and 2 inhibited LPS-induced nuclear factor-κB (NF-κB) activation by suppressing phosphorylation of IkappaB (IκB). These results indicated that the anti-inflammatory effects of these benzaldehyde derivatives in LPS-stimulated RAW264.7 macrophages were due to the inactivation of the NF-κB pathway. In addition, compounds 1 and 2 induced heme oxygenase-1 (HO-1) expression through the nuclear transcription factor-E2-related factor 2 (Nrf2) translocation. The inhibitory effects of compounds 1 and 2 on the production of pro-inflammatory mediators and on NF-κB binding activity were reversed by HO-1 inhibitor tin protoporphyrin (SnPP). Thus, the anti-inflammatory effects of compounds 1 and 2 also correlated with their ability of inducing HO-1 expression.
    International Journal of Molecular Sciences 12/2014; 15(12):23749-65. DOI:10.3390/ijms151223749 · 2.46 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In the course of a search for anti-inflammatory metabolites from marine-derived fungi, methylpenicinoline (1) was isolated from a marine isolate of Penicillin sp. Compound 1 inhibited lipopolysaccharide (LPS)-stimulated nitric oxide (NO) production by suppressing the expression of inducible NO synthase (iNOS) in RAW264.7 macrophages and BV2 microglia. It also attenuated prostaglandin E2 (PGE2) production by suppressing cyclooxygenase-2 (COX-2) expression in a concentration-dependent manner (from 10 μM to 80 μM) without affecting cell viability. In addition, compound 1 reduced the production of the pro-inflammatory cytokine interleukin-1β (IL-1β). In a further study designed to elucidate the mechanism of its anti-inflammatory effects, compound 1 was shown to block nuclear factor-kappa B (NF-κB) activation in LPS-induced RAW264.7 macrophages and BV2 microglia by inhibiting the phosphorylation of inhibitor kappa B-α (IκB-α), thereby suppressing the nuclear translocation of NF-κB dimers, namely p50 and p65, that are known to be crucial molecules associated with iNOS and COX-2 expression. In addition, compound 1 inhibited the activation of mitogen-activated protein kinase (MAPK) pathways. Taken together, the results suggest that compound 1 might be a valuable therapeutic agent for the treatment of anti-inflammatory and anti-neuroinflammatory diseases.
    Molecules 11/2014; 19(11):18073-18089. DOI:10.3390/molecules191118073 · 2.10 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Three strains of an unidentified Penicillium species were isolated during a fungal diversity survey of marine environments in Korea. These strains are described here as a new species following a multigene phylogenetic analyses of nuc rDNA internal transcribed spacer barcodes (ITS1-5.8S-ITS2), genes for β-tubulin, calmodulin and RNA polymerase II second largest subunit, and observation of macro- and micromorphological characters. Phylogenetic analyses revealed that the three strains formed a strongly supported monophyletic group distinct from previously reported species of section Aspergilloides. Morphologically this species can be distinguished from its sister species, P. crocicola, by the reverse color on Czapek yeast autolysate agar, abundant production of sclerotia on malt extract agar and colony characters on yeast extract sucrose agar. We name this new species P. jejuense, after the locality where it was discovered. At 25 C for 7 d, P. jejuense colonies grew to 55-60 mm on CYA, 45-48 mm on MEA, 48-52 mm on YES and 23-26 mm on CREA. Conidia (2.2-3.4 × 2.0-2.6 μm) and sclerotia (160-340 × 125-210 μm) were globose to ellipsoidal.
    Mycologia 10/2014; 107(1). DOI:10.3852/14-180 · 2.13 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Aim. The objective was to evaluate the synergistic effects of fermented rice extracts (FRe) on the laxative and probiotic properties of yoghurt in rats with loperamide-induced constipation. Methods. After constipation induction, yoghurt containing FRe (BFRe; 0.05%, 0.1%, or 1%) was administered orally once per day for 6 days. Results. Loperamide treatment caused marked decreases in fecal pellet numbers and water content discharged, as well as in the surface mucosal thickness of the colonic lumen, intestinal charcoal transit ratio, thickness, and number of mucous-producing goblet cells in the colonic mucosa, whereas it increased the remnant fecal pellet number and the mean diameter of the colonic lumen. However, this loperamide-induced constipation was ameliorated by treatment with FRe, yoghurt single formula, or 0.05%, 0.1%, or 1% BFRe (10 mL/kg). Additionally, the viable numbers of Lactobacillus in the cecal contents and feces were markedly higher than those in constipated rats. Moreover, greater probiotic and laxative effects were detected in BFRe-treated rats than in rats treated with equivalent doses of yoghurt or FRe single formula. Conclusion. The results suggest that addition of FRe to liquid yoghurt will enhance the probiotic and beneficial laxative effects of yoghurt in the digestive tract, without causing side effects.
    Evidence-based Complementary and Alternative Medicine 08/2014; 2014:878503. DOI:10.1155/2014/878503 · 2.18 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The diversity of marine-derived Penicillium from Korea was investigated using morphological and multigene phylogenetic approaches, analyzing sequences of the internal transcribed spacer region, β-tubulin gene, and RNA polymerase subunit II gene. In addition, the biological activity of all isolated strains was evaluated. We tested for the extracellular enzyme activity of alginase, endoglucanase, and β-glucosidase, and antifungal activity against two plant pathogens (Colletotrichum acutatum and Fusarium oxysporum). A total of 184 strains of 36 Penicillium species were isolated, with 27 species being identified. The most common species were Penicillium polonicum (19.6 %), P. rubens (11.4 %), P. chrysogenum (11.4 %), and P. crustosum (10.9 %). The diversity of Penicillium strains isolated from soil (foreshore soil and sand) and marine macroorganisms was higher than the diversity of strains isolated from seawater. While many of the isolated strains showed alginase and β-glucosidase activity, no endoglucanase activity was found. More than half the strains (50.5 %) showed antifungal activity against at least one of the plant pathogens tested. Compared with other strains in this study, P. citrinum (strain SFC20140101-M662) showed high antifungal activity against both plant pathogens. The results reported here expand our knowledge of marine-derived Penicillium diversity. The relatively high proportion of strains that showed antifungal and enzyme activity demonstrates that marine-derived Penicillium have great potential to be used in the production of natural bioactive products for pharmaceutical and/or industrial use.
    Antonie van Leeuwenhoek 08/2014; 106:331-345. DOI:10.1007/s10482-014-0205-5 · 2.14 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: New in vitro anti-diabetes makgeolli was produced from rice by adding various quantities of Laminaria japonica, and the fermentation characteristics of the L. japonica makgeolli during the fermentation process were investigated. The contents of alcohol and reducing sugar, and viable count of yeast, of L. japonica makgeolli were not significantly changed when the proportion of L. japonica was increased. The total acid content decreased with an increase in L. japonica concentration; the pH and total bacterial cell count increased in proportion with the increase in L. japonica concentration. The L. japonica makgeolli contents of free sugars, such as fructose, glucose, and sucrose, and of organic acids, such as acetic acid, citric acid, succinic acid, and lactic acid, were altered during fermentation and showed various patterns. The effects of the quantity of L. japonica added on the acceptability and anti-diabetes activities of L. japonica makgeolli were also investigated. In a sensory evaluation, L. japonica makgeolli brewed by adding 2.5 or 5% L. japonica to the mash showed the best overall acceptability; the 12.5% L. japonica sample was least favored due to its seaweed flavor. L. japonica addition did not increase the peroxynitrite-scavenging activity of makgeolli. L. japonica makgeolli showed potent anti-diabetes activity, particularly that containing >7.5% L. japonica. Therefore, L. japonica makgeolli may represent a new functional makgeolli with anti-diabetes properties.
    06/2014; 19(2):98-107. DOI:10.3746/pnf.2014.19.2.098
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: During a survey of marine fungi from the waters surrounding Jeju Island, Korea, several Penicillium strains were isolated from seawater and marine sponges. Based on morphological characteristics and phylogenetic analyses of the internal transcribed spacer and RNA polymerase subunit II, four strains were identified as Penicillium antarcticum, a fungus that, to the best of our knowledge, had not been previously reported in Korea. Here, we provide detailed descriptions of the morphological characteristics and extracellular enzyme activities of the four strains.
    Mycobiology 06/2014; 42(2):109-13. DOI:10.5941/MYCO.2014.42.2.109 · 0.51 Impact Factor
  • 06/2014; 6(2):87-98. DOI:10.1007/s13530-014-0192-y
  • [Show abstract] [Hide abstract]
    ABSTRACT: To develop a new preservation method, the antimicrobial activity of grapefruit seed extract (GSE) against Makgeolli-brewing microorganisms and food-borne pathogens was assessed, and a general analysis and sensory evaluation of fresh Makgeolli with added GSE was made. The minimum inhibitory concentration (MIC) values of GSE against 10 strains of Makgeolli-brewing microorganism were 0.0122 to 1.5625 μL/mL. The MIC values against 6 strains of food-borne pathogens were 0.0061 to 0.7813 μL/mL. On addition of 0.1% (v/v) and 0.2% GSE in bottled fresh Makgeolli, no significant difference in the pH, or the contents of total acids, ethanol, or methanol in the Makgeolli, were observed compared with control Makgeolli (with no GSE), during the preservation period (8 weeks) at 10 °C. In the Makgeolli with 0.1% and 0.2% GSE, the total bacterial counts decreased significantly by 4.9% (P < 0.01) and 11.2% (P < 0.001), respectively, versus the control. The decreases in yeast count were significantly lessened by 15.33% and 15.24% (both P < 0.001), respectively, after 8 weeks of storage, compared with the control. In the sensory evaluation of Makgeolli with 0.1% and 0.2% GSE, the refreshment and overall acceptability received significantly better scores than the control (P < 0.01), with no change in sweetness, bitterness, sourness, turbidity, color, or odor. These results suggest that GSE controls the growth of Makgeolli-brewing microorganisms and extends the shelf life (ca. 2 wk), without decreasing overall acceptance.Practical ApplicationA new preservation method for fresh Makgeolli by adding grapefruit seed extract (GSE) was developed. As fresh Makgeolli contains live microorganisms, the preservation period is ∼1 wk, which is relatively short. GSE controls the growth of Makgeolli-brewing and Makgeolli-spoiling microorganisms. 0.1% to 0.2% GSE is optimum for prolonging the shelf life (2 wk) of bottled fresh Makgeolli, and has no adverse effect on overall acceptability. We demonstrated that GSE is an effective natural additive that prolongs the shelf life of fresh Makgeolli with no significant loss in quality.
    Journal of Food Science 04/2014; 79(6). DOI:10.1111/1750-3841.12469 · 1.79 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To determine whether fermented rice extract (FRe) has bifidogenic growth-stimulating effects in vitro, the effects of FRe on the growth of lactic acid bacteria and bifidobacteria were evaluated. Treatment with 0.2% FRe stimulated the growth of three strains of lactic acid bacteria (Lactobacillus acidophilus, Streptococcus thermophilus, and Bifidobacterium lactis), significantly increasing the number of cells by 11 - 53 fold after 12 - 18-h incubation compared with the control (p < 0.05). HPLC analysis indicated that the panose content of the FRe powder was 6.7%. The growth-stimulating effects of FRe on bifidobacteria and lactic acid bacteria were likely due to panose, and additional unknown and/or known substances in the FRe. Based on these results, we propose that FRe could be used as a growth stimulator for bifidogenic and lactic acid bacteria in pharmaceutical and food applications.
    Food Science and Technology Research 03/2014; 20(2):479-483. DOI:10.3136/fstr.20.479 · 0.36 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: One new diketopiperazine alkaloid, deoxydihydroisoaustamide (I), and a new metabolite (II) are isolated together with the already known and structurally related deoxyisoaustamide.
    ChemInform 02/2014; 45(8). DOI:10.1002/chin.201408221
  • [Show abstract] [Hide abstract]
    ABSTRACT: The aim of present research was to determine the acute oral toxicity of fermented rice extracts (FREs), in female and male ICR mice. To investigate the toxicity and identify target organs, FREs were orally administered once to male and female ICR mice at doses of 0 (vehicle control), 500, 1000, or 2000 mg/kg body weight (BW). Effects on mortality, BW, and clinical signs were monitored over 14 days, including changes in the weights and histopathological characteristics of 14 organs, as described in the Korea Food and Drug Administration (KFDA) Guidelines (2009-116, 2009). No treatment-related mortality was observed during the 14-day observation period in either gender. In addition, no FRE-related change was observed in BW or organ weight (OW), clinical indicators, or histopathological findings in this study. Our results suggest that the FRE is non-toxic in mice and is therefore likely to be safe for clinical use. The approximate LD and LD50 in mice after single oral dose of FRE are greater than 2000 mg/kg in female and male ICR mice. Additionally, no specific target organ or negative clinical indicator was detected in this study.
    Pakistan journal of pharmaceutical sciences 01/2014; 27(1):129-37. · 0.95 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In the course of a bioassay-guided study of metabolites from the marine fungus Eurotium sp. SF-5989, two diketopiperazine type indole alkaloids, neoechinulins A and B, were isolated. In this study, we investigated the anti-inflammatory effects of neoechinulins A (1) and B (2) on lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Neoechinulin A (1) markedly suppressed the production of nitric oxide (NO) and prostaglandin E2 (PGE2) and the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in a dose dependent manner ranging from 12.5 µM to 100 µM without affecting the cell viability. On the other hand, neoechinulin B (2) affected the cell viability at 25 µM although the compound displayed similar inhibitory effect of NO production to neoechinulin A (1) at lower doses. Furthermore, neoechinulin A (1) decreased the secretion of pro-inflammatory cytokines, such as tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). We also confirmed that neoechinulin A (1) blocked the activation of nuclear factor-kappaB (NF-κB) in LPS-stimulated RAW264.7 macrophages by inhibiting the phosphorylation and degradation of inhibitor kappa B (IκB)-α. Moreover, neoechinulin A (1) decreased p38 mitogen-activated protein kinase (MAPK) phosphorylation. Therefore, these data showed that the anti-inflammatory effects of neoechinulin A (1) in LPS-stimulated RAW264.7 macrophages were due to the inhibition of the NF-κB and p38 MAPK pathways, suggesting that neoechinulin A (1) might be a potential therapeutic agent for the treatment of various inflammatory diseases.
    Molecules 11/2013; 18(11):13245-59. DOI:10.3390/molecules181113245 · 2.10 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the course of studies on bioactive metabolites from marine fungi, a new 10-membered lactone, named penicillinolide A (1) was isolated from the organic extract of Penicillium sp. SF-5292 as a potential anti-inflammatory compound. The structure of penicillinolide A (1) was mainly determined by analysis of NMR and MS data and Mosher's method. Penicillinolide A (1) inhibited the production of NO and PGE2 due to inhibition of the expression of iNOS and COX-2. Penicillinolide A (1) also reduced TNF-α, IL-1β and IL-6 production, and these anti-inflammatory effects were shown to be correlated with the suppression of the phosphorylation and degradation of IκB-α, NF-κB nuclear translocation, and NF-κB DNA binding activity. In addition, using inhibitor tin protoporphyrin (SnPP), a competitive inhibitor of HO activity, it was verified that the inhibitory effects of compound 1 on the production of pro-inflammatory mediators and NF-κB DNA binding activity were partially associated with HO-1 expression through Nrf2 nuclear translocation.
    Marine Drugs 11/2013; 11(11):4510-26. DOI:10.3390/md11114510 · 3.51 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The antibacterial activity of various saturated fatty acids (SFA) and unsaturated fatty acids (USFA) against different oral pathogens which are implicated in the cause of dental caries, stomatitis, gingivitis, and periodontitis was examined. The saturated fatty acids Pa, StA and ArA, and the unsaturated omega-7 fatty acids PLA and omega-9 fatty acids OA showed either none to low antimicrobial activity against all of the 12 oral pathogenic strains used in this study. In contrast, the omega-3 PUFAs, ALA, SDA, EPA and DHA, and the omega-6 PUFAs, LA, GLA, and AA showed considerable antimicrobial activity against 8, 7, 6 and 5 strains, and 6, 10 and 5 strains, respectively. In particular, the omega-3 and omega-6 PUFAs showed strong antimicrobial activity against Porphyromonas gingivalis KCTC 381, the cause of periodontitis, and against Aggregatibacter segnis KCTC 5968, Fusobacterium nucleatum subsp. Polymorphum KCTC 5172 and Prevotella intermedia KCTC 25611, all organisms implicated in the cause of gingivitis. To date, no bacterial resistance to free fatty acids has been encountered and no resistance phenotype has emerged. Therefore, these results suggest that PUFAs may be useful in the development of therapeutic agents for oral diseases, and in particular, in the development of agents that have minimal side effects and against which there is no bacterial resistance.
    Journal of Environmental Biology 07/2013; 34(4):673-6. · 0.55 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Property changes and bacterial characterizations by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) were investigated during the fermentation of Makgeollies by 5 isolated yeast strains. Changes of pH were large between day 0 (pH 6) and day 2 (pH 3) and showed less variation after then. ANOVA analyses revealed that pHs were statistically different with fermentation times (p
    06/2013; 23(6). DOI:10.5352/JLS.2013.23.6.796