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Fungal species belonging to the genus Penicillium are indigenous to a wide range of natural environments. Since the first published reports detailing the discovery of Penicillium, new species have been identified in various countries, including Korea. We present here a full characterization of five species of Penicillium that were previously unreported in Korea. Based on the morphologic characteristics and sequences of genes encoding fungal β–tubulin and calmodulin, we identified five Penicillium species, including P. hetheringtonii, P. sublectaticum, and P. jacksonii, which have been unrecorded in Korea, and confirming P. maximae and P. cremeogriseum, as the endophytic fungi isolated in Gyeongsang province, Korea. In this article, we provide detailed morphological descriptions of these fungal species.

Adlay seed samples were collected from three adlay growing regions (Yeoncheon, Hwasun, and Eumseong region) in Korea during 2012. Among all the samples collected, 400 seeds were tested for fungal occurrence by standard blotter and test tube agar methods and different taxonomic groups of fungal genera were detected. The most predominant fungal genera encountered were Fusarium, Phoma, Alternaria, Cladosporium, Curvularia, Cochliobolus and Leptosphaerulina. Fusarium species accounted for 45.6% of all species found; and, with phylogenetic analysis based on the combined sequences of two protein coding genes (EF-1α and β-tubulin), 10 Fusarium species were characterized namely, F. incarnatum (11.67%), F. kyushuense (10.33%), F. fujikuroi (8.67%), F. concentricum (6.00%), F. asiaticum (5.67%), F. graminearum (1.67%), F. miscanthi (0.67%), F. polyphialidicum (0.33%), F. armeniacum (0.33%), and F. thapsinum (0.33%). The Fusarium species were then examined for their morphological characteristics to confirm their identity. Morphological observations of the species correlated well with and confirmed their molecular identification. The ability of these isolates to produce the mycotoxins fumonisin (FUM) and zearalenone (ZEN) was tested by the ELISA quantitative analysis method. The result revealed that FUM was produced only by F. fujikuroi and that ZEN was produced by F. asiaticum and F. graminearum.

Organic fertilizers were applied in four different forms: mixed organic matter, fermentation cake, bacterial culture, and rice husks, excluding conventional chemical fertilizer and non-treatment used as control. The results showed that soil pH was acidified after fermentation cake and chemical fertilizer treatment. Specifically, chemical fertilizer treatment showed higher phosphoric-acid content than other treatments, while total N content was higher in fermentation cake, mixed organic matter and chemical fertilizer. Growth of Codonopsis lanceolata showed superior tendency in the treatment of mixed organic matter and fermentation cake. Lancemacides, the major saponin of C. lanceolata, could be identified as foetidissimoside A, lancemaside A, lancemaside B, and lancemaside D. However, among them, quantitative analysis could not be conducted on foetidissimoside A due to its very low content, and lancemaside A was the most abundant saponin in the root from all the treatments. The content of lancemaisde A according to organic fertilizer application showed the highest value of 0.12 mg g-1 in the treatment of mixed organic matter, followed by the fermentation cake, bacterial culture, non-treatment, rice husks and chemical fertilizer, in that order. The content of lancemaside B and D was very low compared to lancemaside A, and there was no difference among treatments. Therefore, it was verified that the growth of C. lanceolata was superior in application of mixed organic matter and fermentation cake, and the major saponin, lancemaside A, was also increased. [ABSTRACT FROM AUTHOR]

The dynamic interaction between the catenary and the pantographs of high-speed trains is a very important factor that affects the stable electric power supply. In order to design a reliable current collection system, a multibody simulation model can provide an efficient and economical method to analyze the dynamic behavior of the catenary and pantograph. In this article, a dynamic analysis method for a pantograph–catenary system for a high-speed train is presented, employing absolute nodal coordinates and rigid body reference coordinates. The highly flexible catenary is modeled using a nonlinear continuous beam element, which is based on an absolute nodal coordinate formulation. The pantograph is modeled as a rigid multibody system. The analysis results are compared with experimental data obtained from a running high-speed train. In addition, using a derived system equation of motion, the calculation method for the dynamic stress in the catenary conductor is presented. This study may have significance in providing an example that a structural and multibody dynamics model can be unified into one numerical system. [ABSTRACT FROM AUTHOR]

Recently matured silkworm powder was developed by RDA. In this study, the effect of pulverizing method on the particle size of matured silkworm powder was examined. FESEM was performed to observe the morphology and to measure the particle size of silkworm powder. Particle morphology of air-jet mill pulverized powder was round and smooth, however, those of roller-mill and hammer-mill pulverized mature silkworm was more harsh and square. Particle size was varied with pulverizing technique as follows; 1.1 μm (air-jet mill), 10 μm (roller mill), and 120 μm (hammer mill), respectively. A proximate analysis results of air-jet mill powder showed that crude protein, crude lipid, crude fiber, and ash was 73%, 12%, 1.95%, and 3.4%, respectively. According to our results, air-jet mell technique might be used to make a tiny matured silkworm powder. [ABSTRACT FROM AUTHOR]

Methicillin-resistant Staphylococcus aureus (MRSA) along with other resistant bacteria have become a significant social and clinical problem. Therefore, there is an urgent need to develop bioactive compounds from natural products as alternatives to the very few antibiotics that remain effective. Recently, the efflux mechanism has been identified as the main contributor to antibiotic resistance in bacteria. This study therefore aimed to evaluate tetrandrine (TET), an efflux pump inhibitor (EPI), as a potential antibiotic against MRSA. We investigated the antimicrobial activity of TET against 17 MRSA strains, of which 3 selected strains were studied in further detail using a time-kill assay. When these bacterial al strains (1 x 106 colony-forming units (cfu)/ml) were incubated with TET in a time-kill assay, log-scale bactericidal activity was observed, which lasted for 24 hr. In addition, TET exhibits a synergistic effect when combined with the multi-drug resistance (MDR)-efflux pump substrate ethidium bromide (EtBr). Structure-function studies of the antibiotic activity of TET in combination with EtBr may lead to the discovery of more effective efflux pump inhibitors. [ABSTRACT FROM AUTHOR]

Sanguinarine is a benzophenanthridine alkaloid derived from the root of Sanguinaria canadensis. It is known to perform a wide spectrum of biological activities. The aim of this study is to examine the antimicrobial actions of sanguinarine against methicillin-resistant Staphylococcus aureus (MRSA). Sanguinarine antimicrobial activity was assessed by broth dilution method; its mechanism of action was investigated by bacteriolysis, detergent or ATPase inhibitors and transmission electron microscopy were used to monitor the survival characteristics and the changes in bacteria morphology. The activity of sanguinarine against MRSA strains ranged from 3.12 to 6.25 μg/ml, while the minimum inhibitory concentrations of the two reference strains are 3.12 μg/ml and 1.56 μg/ml. The treatment of the cells with sanguinarine induced the release of membrane-bound cell wall autolytic enzymes, which eventually resulted in lysis of the cell. The OD600s of the suspensions treated with the combination of Tris-(hydroxymethyl) aminomethane and Triton X-100 with sanguinarine were reduced to 40% and 8%, respectively. Transmission electron microsco py of MRSA treated with sanguinarine showed alterations in septa formation. The predisposition of lysis and the altered morphology seen by transmission electron microscopy suggest that sanguinarine compromises the cytoplasmic membrane. [ABSTRACT FROM AUTHOR]