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A Gram-stain-negative, non-motile and facultative anaerobic bacterium, designated CAM-8T, was isolated from an artificial fountain at Chonbuk National University, South Korea. The novel strain grew at 20–37 °C (optimum 25 °C), pH 5.5–7.0 (optimum 6.0) and with 0–2 % NaCl (optimum 0 %). Oxidase and catalase activities were positive. The cell morphology of strain CAM-8T was atypical rods 0.6–0.8 µm in width and 4.5–6.5 µm in length, with a peaked tip and sometimes a bulb shape. CAM-8T existed as single cells, and as pairs or chains of cells. The phylogenetic analysis of 16S rRNA gene sequences indicated that strain CAM-8T clustered with Gemmobacter nectariphilus JCM 11959T and Gemmobacter megaterium JCM 18498T within the genus Gemmobacter . The DNA G+C content of strain CAM-8T was 65.9 mol%. The respiratory quinone was ubiquinone Q-10. The major fatty acids were C18 : 1 ω7c and/or C18 : 1 ω6c. The polar lipids of strain CAM-8T consisted of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, two uncharacterized phospholipids, an uncharacterized aminolipid, an uncharacterized glycolipid, an uncharacterized aminophospholipid and four uncharacterized lipids. On the basis of phenotypic, phylogenetic and chemotaxonomic data, strain CAM-8T (=KACC 19224T=JCM 31905T) is considered to represent a novel species of the genus Gemmobacter , for which the name Gemmobacter straminiformis sp. nov. is proposed.

A Gram-negative, facultative anaerobic, rod-shaped, motile by means of a polar flagellum, greenish-yellow-pigmented bacterial strain (designated strain JJ3220T) was isolated from an artificial lake in South Korea and characterized using a polyphasic approach. The 16S rRNA gene sequence of strain JJ3220T indicated that the isolate belongs to the family Rhodocyclaceae, and that it exhibits 96.4% similarity to Uliginosibacterium paludis KBP-13T. The major cellular fatty acids of the novel strain were C14:0, C16:0, and summed feature 3 (C16:1 ω6c and/or C16:1 ω7c). Strain JJ3220T had flexirubin-type pigments. The DNA G+C content of the strain was 62.8%. The major respiratory quinone and major polar lipid of strain JJ3220T were ubiquinone-8 and phosphatidylethanolamine, respectively. Based on the morphological and physiological properties and biochemical evidence presented, it can be concluded that strain JJ3220T represents a novel species of the genus Uliginosibacterium. The type strain Uliginosibacterium flavum is JJ3220T (=KACC 17644T =JCM 19465T).

A taxonomic study was carried out on a novel bacterial strain, designated MIC2059T, which was isolated from Ungok Wetland of Gochang in Korea. Cells of the isolate were found to be Gram-stain-negative, rod-shaped and motile. Comparison of the 16S rRNA gene sequences indicated that the isolate belonged to the family Rhodocyclaceae, with Uliginosibacterium gangwonense as its closest relative, with a similarity of 94.8 %. It contained summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c), C16 : 0, summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c) and C12 : 0 3-OH as the major fatty acids and Q8 as the respiratory ubiquinone. The polar lipid profile of strain MIC2059T revealed the presence of phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol as major polar lipids. In addition, phosphatidylserine, an unidentified aminophospholipid and unidentified lipids were present in small amounts. The DNA G+C content of the strain was 65.1 mol%. On the basis of the evidence presented, it is concluded that strain MIC2059T represents a novel species of a novel genus within the family Rhodocyclaceae, for which the name Niveibacterium umoris gen. nov., sp. nov. is proposed. The type strain is MIC2059T ( = KACC 17062T = JCM 18716T).

A novel bacterial strain, designated GCR0105T, was isolated from a water sample of the Mangyung estuary enclosed by the Saemangeum Embankment, located in JEOLlabuk-do, South Korea. Cells of strain GCR0105T were Gram-stain-negative, non-motile and rod-shaped. Colonies of strain GCR0105T were pale yellow-pigmented on R2A agar and nutrient agar media, and were able to grow at 15–30 °C (optimum 25 °C) and pH 6.5–8.5 (optimum pH 7.5). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain GCR0105T was related most closely to Flavisolibacter ginsengisoli Gsoil 643T (93.14 % similarity). The polar lipid profile of strain GCR0105T comprised phosphatidylethanolamine, two unknown aminolipids, an unknown aminophospholipid and four unknown lipids. The DNA G+C content of strain GCR0105T was 42.9 mol% and the respiratory quinone was MK-7.On the basis of phenotypic, chemotaxonomic and phylogenetic properties, strain GCR0105T represents a novel species in a new genus within the family Chitinophagaceae, for which the name Flaviaesturariibacter amylovorans gen. nov., sp. nov. is proposed. The type strain of Flaviaesturariibacter amylovorans is GCR0105T ( = KACC 16454T = JCM 17919T).

Mycotoxins are potentially dangerous contaminants of livestock feeds. In this study, we measured the levels of fumonisin B1 and glycated fumonisin B1 in feedstuffs and then investigated the ability of the extrusion heating regimen to convert the most prevalent mycotoxin contaminant, fumonisin B1, to a less toxic glycated form. All feed samples were analyzed with fully validated methods. All measured concentrations of fumonisin B1 were below harmful thresholds, including European Union-recommended levels or US Food and Drug Administration action levels. Because fumonisin B1 was highly contaminated mycotoxin in our present investigation and fumonisin B1 has been shown to be less toxic following Maillard type reaction with reducing sugar, we examined the formation of fumonisin B1 derivatives by Maillard reaction under extrusion process conditions. We employed a variety of tandem mass spectrometric methodologies to selectively detect fumonisin B1 derivatives and to elucidate their structures partially. We found that compounds of m/z 736 were more likely artifacts or side reaction products rather than glycation products. N-(carboxymethyl) fumonisin B1 of m/z 780 and other major glycation products of m/z 794 and 810 were not detected, and only negligible amounts of methylene fumonisin B1 was found in 10 extruded feed samples. Therefore, either the tested extrusion conditions did not induce fumonisin B1 glycation or the glycation products simply could not be detected by the method employed in this study.

A taxonomic study was carried out on a novel bacterial strain, designated MIC1008T, which was isolated from the Gomso salt pan, located in Buan County, Korea. Cells were Gram-stain-negative, aerobic, non-motile and moderately halophilic rods, 0.2–0.4 µm wide and 0.7–1.2 µm long. The optimum temperature and pH for growth were 25 °C and pH 6.5–8.5, respectively. Catalase and oxidase activities were positive. Carotenoid pigments were produced. Comparison of 16S rRNA gene sequences indicated that the isolate belonged to the genus Psychroflexus , with Psychroflexus halocasei WCC 4520T as its closest relative, with a 16S rRNA gene sequence similarity of 95.4 %. The isolate contained iso-C15 : 0, iso-C15 : 1 G, iso-C17 : 0 3-OH, anteiso-C15 : 0 and iso-C15 : 0 3-OH as the major fatty acids and menaquinone MK-6 as the isoprenoid quinone. The major polar lipid profile of strain MIC1008T revealed the presence of phosphatidylethanolamine, an unidentified aminolipid and two unidentified lipids. The DNA G+C content of the isolate was 32.9 mol%. On the basis of the evidences presented, it is concluded that strain MIC1008T represents a novel species of the genus Psychroflexus within the family Flavobacteriaceae , for which the name Psychroflexus http://dx.doi.org/10.1601/nm.8182 salarius sp. nov. is proposed. The type strain is MIC1008T ( = KACC 17063T = DSM 25661T).

A Gram-stain-negative, rod-shaped, non-motile and yellow-pigmented bacterial strain, designated strain JJ013T, was isolated from an artificial lake in Jeollabuk-do, South Korea, and characterized using a polyphasic approach. The 16S rRNA gene sequence of strain JJ013T indicated that the isolate belonged to the family Flavobacteriaceae and exhibited similarity levels of 96.6 % to the type strains of Flavobacterium cheonanense and Flavobacterium koreense and 96.5 % to the type strain of Flavobacterium chungnamense . Growth was observed at 20–30 °C and pH 5.0–7.0. The major cellular fatty acids of the novel strain were iso-C15 : 0 (27.5 %), iso-C15 : 1 G (17.8 %), iso-C17 : 0 3-OH (9.4 %) and iso-C15 : 0 3-OH (9.2 %). Flexirubin-type pigments were present. The DNA G+C content of strain JJ013T was 33.9 mol%, the major respiratory quinone was menaquinone-6 (MK-6) and the major polyamine was sym-homospermidine. The polar lipid profile of the strain JJ013T consisted of a phosphatidylethanolamine (PE), two unknown aminolipids (AL1–2), three unidentified lipid (L1–3) and an unknown glycolipid (GL). On the basis of the morphological and physiological properties and biochemical evidence presented, it is concluded that strain JJ013T represents a novel species of the genus Flavobacterium , for which the name Flavobacterium aciduliphilum sp. nov. is proposed; the type strain is JJ013T ( = KACC 16594T = JCM 18211T). Since C15 : 0, which is known as a predominant fatty acid of the genus Flavobacterium was not detected in the novel strain and other reference strains, we propose an emended description of the genus Flavobacterium .

Gochujang, a savory and pungent fermented sauce, is a Korean ethnic food composed primarily of fermented soybean cake, red pepper powder, glutinous rice, and salt. Industrial gochujang is fermented following inoculation with Aspergillus oryzae and Bacillus subtilis as starter microorganisms. In contrast, a wide variety of natural fungi and bacteria are used in fermentation and aging of artisanal gochujang, the aging period of which is longer than 6 months. We monitored ochratoxin A (OTA) contamination of red pepper and gochujang available in the Korean retail market and explored the possibility that microorganisms in gochujang might degrade OTA present in contaminated red pepper during soybean fermentation and aging. We report here that OTA can be easily biotransformed serially to several products by B. Subtilis (KTCT 1021) under the conditions of our experiments. The dynamic microbial activity in gochujang might contribute to the low occurrence of ochratoxin A in this product despite the use of highly contaminated pepper powder, one of the main ingredients of gochujang. At the same time, however, an inappropriate fermentation process and the long aging period are assumed to be sources of contamination. Studies to identify critical control points and to prevent fungal spoilage by the development of high quality starters should be followed up to enable the artisan to produce OTAfree gochujang.

The hydrophobic and hydrophilic properties of the surface of poly-ether sulfone (PES) films were controlled by an atmospheric pressure plasma (AP) treatment using reactive gases (Ar/H(2) and Ar/O(2)). The surface properties of the Ar/H(2) and Ar/O(2) in series AP-treated PES films showed higher surface roughness (approximately 120%), surface energy (approximately 30%) and hydrophilic properties (oxygen content approximately 10%) than the Ar/O(2) AP-treated PES film. The protein staining results confirmed that an activated region on the patterned PES film with high selectivity and sensitivity was well-defined and formed. This method is suitable for fabricating flexible protein adhesive chips with uniform biomolecular adhesive properties.

In examining the production of valuable compounds by marine microorganisms, we isolated a novel yeast strain that produces a large amount of squalene and several polyunsaturated fatty acids. Molecular and phylogenetic analyses of the ribosomal DNA suggest that the isolate belongs to the genus Pseudozyma, which comprises ustilaginomycetous anamorphic yeasts. The nucleotide sequence of an internally transcribed spacer region from isolate Pseudozyma sp. JCC207 showed 98% similarity with those of Pseudozyma rugulosa and Pseudozyma aphidis, which are close relatives of the isolate. In considering use of Pseudozyma sp. JCC207 for squalene production, the efficiency of squalene production was investigated under different conditions. Glucose was the best carbon source for the production of squalene. In the presence of yeast extract, squalene production was activated and an optimum ratio of glucose to yeast extract was 4.5. For the optimal squalene production, the concentration of glucose was 40 g l(-1) and the best nitrogen source was sodium nitrogen. Pseudozyma sp. JCC207 was shown to produce up to 5.20 g/L of biomass and 340.52 mg/L of squalene. In an optimal condition, the content and yield of squalene produced by Pseudozyma sp. JCC207 were much greater than those obtained from microorganisms previously reported as squalene producers. We identified, classified, and characterized Pseudozyma sp. JCC207 as a novel squalene producer. The squalene production rate of Pseudozyma sp. JCC207 makes it an ideal candidate for the commercialization of microbial squalene.

The antimicrobial killing activity toward methicillin-resistantStaphylococcus aureus(MRSA) has been a serious emerging global issue. In a continuing search for compounds with antibacterial activity against several microorganisms includingS. aureusand MRSA, ann-hexane extract ofMagnolia officinaliswas found to contain magnolol. This compound exhibited potent activity againstS. aureus, standard methicillin-susceptibleS. aureus(MSSA), and MRSA as well as clinical MRSA isolates. When combined with oxacillin, the antibacterial activities of magnolol and honokiol against the MRSA strain were increased compared to single treatment without antibiotics at 10 µg/mL and 25 µg/mL, respectively. These activities of magnolol and honokiol were dose dependent. Also, magnolol showed synergistic effects with oxacillin against 13 clinical isolates of MRSA. It was determined that magnolol and honokiol had a synergistic effect with oxacillin against MRSA strain. Furthermore, the magnolol inhibited the expression of the resistant genes,mecA, mecI, femA, andfemB, in mRNA. We concluded that the antibacterial activity of magnolol against MRSA strain is more related to themecI’s pathway and components of the cell wall thanmecR1. Therefore, the results obtained in this study suggest that the combination of magnolol and antibiotics could lead to the development of new combination antibiotics against MRSA infection.

The wettability of electrospun poly(epsilon-caprolactone) (PCL) mats was improved by co-electrospinning with poly(vinyl alcohol) (PVA), by double-spinneret electrospinning method. The improved hydrophilicity of the hybrid PCL/PVA mats was confirmed by water contact angle measurement. The in vitro cell attachment on the hydrophobic PCL and hydrophilically modified PCL/PVA mats was compared by culture studies using human prostate epithelial cells (HPECs). The stability of water-soluble PVA component in the electrospun PCL/PVA mats was checked by thermogravimetric analysis and intensity of fluorescence material after immersion in water for 7 days. The images from scanning electron microscopy, field emission scanning electron microscopy, and optical microscopy showed that the attachment and proliferation rate of HPECs were improved by introducing PVA into the electrospun PCL mats.

Biosorption of heavy metals and dyes is a promising technology that involves the removal of toxic metals from industrial wastes. The present study aims to screen the bacterial strains isolated from soils and polluted pond for their potential biosorption of both cationic dye and cadmium. Bacillus catenulatus JB-022 strain removed 58% and 66% of cationic basic blue 3 (BB3) and cadmium (Cd(II)) at the respective concentrations of 2000 mg/L and 150 mg/L. The biosorption equilibrium data were well fitted by the Langmuir adsorption isotherm, and the kinetic studies indicated that the biosorption followed the pseudo-second-order model. The biosorption kinetics showed that the equilibrium was reached within 10 min and 5 min for BB3 and Cd(II), respectively. According to the Langmuir model, the maximum uptakes of BB3 and Cd(II) by the JB-022 biomass were estimated to be 139.74 and 64.28 mg/g, respectively. To confirm the surface morphology and functional groups, field emission scanning electron microscope, energy-dispersive X-ray spectrometer, X-ray diffraction, and Fourier transform infrared spectroscopy analyses were carried out, and the results revealed that the biomass of JB-022 has carboxyl and phosphonate groups as potential surface functional groups capable of binding to cationic pollutants. In conclusion, B. catenulatus JB-022 is proposed as an excellent biosorbent with potentially important applications in removal of cationic pollutants from wastewaters.

In fungi, cell wall plays an important role in growth and development. Major macromolecular constituents of the aspergilli cell wall are glucan, chitin, and protein. We examined the chemical composition and structure of the Aspergillus nidulans hyphal wall surface by an atomic force microscope (AFM). To determine the composition of the cell wall surface, the adhesion forces of commercially available beta-glucan, chitin, and various proteins were compared to those of corresponding fractions prepared from the hyphal wall. In both setups, the adhesion forces of beta-glucan, chitin, and protein were 25-50, 1000-3000, and 125-300 nN, respectively. Adhesion force analysis demonstrated that the cell surface of the apical tip region might contain primarily chitin and beta-glucan and relatively a little protein. This analysis also showed the chemical composition of the hyphal surface of the mid-region would be different from that of the apical region. Morphological images obtained by the tapping mode of AFM revealed that the hyphal tip surface has moderate roughness.