Pedobacter panacis sp. nov., isolated from Panax ginseng soil

Singh, P.,Singh, H.,Kim, Y. J.,Yang, D. C. Kluwer Academic Publishers [etc.] 2017 Antonie van Leeuwenhoek Vol.110 No.2

<P>A novel strain, DCY108(T) was isolated from soil of a Panax ginseng field, Yeoncheon province (38A degrees 04'N 126A degrees 57'E), Republic of Korea. Strain DCY108(T) is Gram-negative, non-motile, non-flagellate, rod-shaped, and aerobic. The bacterium grows optimally at 25-30 A degrees C, pH 6.5-7.0 and 1 % NaCl. Phylogenetically, strain DCY108(T) is closely related to Pedobacter jejuensis JCM 18824(T), Pedobacter aquatilis JCM 13454(T), Pedobacter kyungheensis LMG 26577(T) and the type strain of the genus Pedobacter heparinus DSM 2366(T). The DNA-DNA relatedness values between strain DCY108(T) and its close phylogenetic neighbors were below 30.0 %. The DNA G+C content of strain DCY108(T) was determined to be 45.1 mol%. The predominant quinone was menaquinone 7 (MK-7). The major polar lipids were identified as phosphatidylethanolamine and three unidentified aminolipids AL1, AL13 and AL17. Iso-C-15:00, iso-C(17:0)3OH and summed feature 3 (C-16:1 omega 7c/C-16:1 omega 6c) were identified as the major fatty acids present in strain DCY108(T). The results of physiological and biochemical tests allowed strain DCY108(T) to be differentiated phenotypically from other recognized species belonging to the genus Pedobacter. Therefore, it is suggested that the newly isolated organism represents a novel species, for which the name Pedobacter panacis sp. nov is proposed with the type strain designated as DCY108(T) (=CCTCCAB 2015196(T) = KCTC 42748(T)).</P>

Structural and optical properties of TiO₂ thin films derived by sol-gel dip coating process

Saini, K.K.,Sharma, S.D.,Chanderkant,Kar, M.,Singh, D.,Sharma, C.P. North-Holland 2007 Journal of non-crystalline solids Vol.353 No.24

Nanocrystalline thin films of titanium dioxide have been fabricated on glass and silica substrates from partially hydrolyzed precursor solution. These films were subjected to heat treatment for 1h at temperatures 100, 200, 300, 400, 500, 600, 700, 800 and 900<SUP>o</SUP>C and characterized by XRD, SEM, XPS and optical techniques. As deposited films are found to be amorphous and also contain hydroxyl and organic functional groups. Films heat treated above 100<SUP>o</SUP>C do not contain hydroxyl and organic functional groups. Microcrystalline behavior is observed in the films heat treated above 300<SUP>o</SUP>C. Crystallite size increases from ∼5 to 50nm as sintering temperature is increased from 300 to 700<SUP>o</SUP>C. Formation of anatase phase with c-axis length 7.03A is observed in the films annealed up to 700<SUP>o</SUP>C. These films peel off from the substrate beyond 700<SUP>o</SUP>C annealing temperature. Density as well as refractive index of the films increases with increase in annealing temperature up to 700<SUP>o</SUP>C. Refractive index is found to show Cauchys behavior. Transmission better than 70% is observed in the visible range. There is a strong absorption around 370nm, which is attributed to band gap absorption of the material.

Achromobacter panacis sp. nov., isolated from rhizosphere of Panax ginseng

Singh, P.,Kim, Y. J.,Singh, H.,Farh, M. E.,Yang, D. C. MICROBIOLOGICAL SOCIETY OF KOREA 2017 JOURNAL OF MICROBIOLOGY -SEOUL- Vol. No.

<P>A novel strain DCY105(T) was isolated from soil collected from the rhizosphere of ginseng (Panax ginseng), in Gochang, Republic of Korea. Strain DCY105(T) is Gram-reaction-negative, white, non-motile, non-flagellate, rod-shaped and aerobic. The bacteria grow optimally at 30 degrees C, pH 6.5-7.0 and in the absence of NaCl. Phylogenetically, strain DCY105(T) is most closely related to Achromobacter marplatensis LMG 26219(T) (96.81%). The DNA G+C content of strain DCY105(T) was 64.4 mol%. Ubiquinone 8 was the major respiratory quinone, and phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol were amongst the major polar lipids. C-16:00, C(8:0)3OH and iso-C(17:0)3OH were identified as the major fatty acids present in DCY105(T). The results of physiological and biochemical tests allowed strain DCY105(T) to be differentiated phenotypically from other recognized species belonging to the genus Achromobacter. Therefore, it is suggested that the newly isolated organism represents a novel species, for which the name Achromobacter panacis sp. nov. is proposed with the type strain designated as DCY105(T) (=CCTCCAB 2015193(T) =KCTC 42751(T)).</P>

Comparative Dielectric and Ferroelectric Characteristics of Bi0.5Na0.5TiO3, CaCu3Ti4O12, and 0.5Bi0.5Na0.5TiO3–0.5CaCu3Ti4O12 Electroceramics

Singh, L.,Yadava, S. S.,Sin, B. C.,Rai, U. S.,Mandal, K. D.,Lee, Y. Springer Science + Business Media 2016 Journal of electronic materials Vol.45 No.6

<P>The dielectric and ferroelectric characteristics of Bi0.5Na0.5TiO3 (BNT), CaCu3Ti4O12 (CCTO), and 0.5Bi(0.5)Na(0.5)TiO(3)-0.5CaCu(3)Ti(4)O(12) (BNT/CCTO) ceramics are compared. X-ray diffraction patterns confirmed the formation of single phase of all the ceramics after sintering at 950A degrees C for 15 h. Scanning electron microscopy images of the sintered ceramics reveal average grain sizes in the range from 200 nm to 2.5 mu m. Energy-dispersive x-ray mapping and x-ray photoelectron spectroscopy show the presence of the elements Bi, Na, Ca, Cu, Ti, and O with uniform distribution in the ceramics. BNT/CCTO exhibits high dielectric constant (epsilon (r) similar to 6.9 x 10(4)) compared with BNT (epsilon (r) similar to 0.13 x 10(4)) and CCTO (epsilon (r) similar to 1.68 x 10(4)) ceramics at 1 kHz and 503 K. The high dielectric constant of BNT/CCTO compared with BNT and CCTO is associated with a major contribution from grain boundaries, as confirmed by impedance and modulus analyses. The P-E hysteresis loop of all the ceramics measured at room temperature and 50A degrees C exhibited typical ferroelectric nature. The remanent polarization (P (r)) of BNT (1.58 mu C/cm(2)) and CCTO (0.654 mu C/cm(2)) ceramics are higher than that of BNT/CCTO (0.267 mu C/cm(2)) ceramic.</P>

Aluminium resistant, plant growth promoting bacteria induce overexpression of Aluminium stress related genes in Arabidopsis thaliana and increase the ginseng tolerance against Aluminium stress

Farh, M.E.A.,Kim, Y.J.,Sukweenadhi, J.,Singh, P.,Yang, D.C. G. Fischer 2017 Microbiological research Vol.200 No.-

<P>Panax ginseng is an important cash crop in the Asian countries due to its pharmaceutical effects, however the plant is exposed to various abiotic stresses, lead to reduction of its quality. One of them is the Aluminum (Al) accumulation. Plant growth promoting bacteria which able to tolerate heavy metals has been considered as a new trend for supporting the growth of many crops in heavy metal occupied areas. In this study, twelve bacteria strains were isolated from rhizosphere of diseased Korean ginseng roots located in Gochang province, Republic of Korea and tested for their ability to grow in Al-embedded broth media. Out of them, four strains (Pseudomonas simiae N3, Pseudomonas fragi N8, Chryseobacterium polytrichastri N10, and Burkholderia ginsengiterrae N11-2) were able to grow. The strains could also show other plant growth promoting activities e.g. auxins and siderophores production and phosphate solubilization. P. simiae N3, C. polytrichastri N10, and B. ginsengiterrae N11-2 strains were able to support the growth of Arabidopsis thaliana stressed by Al while P. fragi N8 could not. Plants inoculated with P. simiae N3, C. polytrichastri N10, and B. ginsengiterrae N11-2 showed higher expression level of Al-stress related genes, AtAIP, AtALS3 and AtALMT1, compared to non-bacterized plants. Expression profiles of the genes reveal the induction of external mechanism of Al resistance by P. simiae N3 and B. ginsengiterrae N11-2 and internal mechanism by C. polytrichastri N10. Korean ginseng seedlings treated with these strains showed higher biomass, particularly the foliar part, higher chlorophyll content than non-bacterized Al-stressed seedlings. According to the present results, these strains can be used in the future for the cultivation of ginseng in Al persisted locations.</P>

Multifunctional Hybrid Nanocarrier: Magnetic CNTs Ensheathed with Mesoporous Silica for Drug Delivery and Imaging System

Singh, Rajendra K.,Patel, Kapil D.,Kim, Jung-Ju,Kim, Tae-Hyun,Kim, Joong-Hyun,Shin, Ueon Sang,Lee, Eun-Jung,Knowles, Jonathan C.,Kim, Hae-Won American Chemical Society 2014 ACS APPLIED MATERIALS & INTERFACES Vol.6 No.4

<P>Here we communicate the development of a novel multifunctional hybrid nanomaterial, magnetic carbon nanotubes (CNTs) ensheathed with mesoporous silica, for the simultaneous applications of drug delivery and imaging. Magnetic nanoparticles (MNPs) were first decorated onto the multiwalled CNTs, which was then layered with mesoporous silica (<I>m</I>SiO<SUB>2</SUB>) to facilitate the loading of bioactive molecules to a large quantity while exerting magnetic properties. The hybrid nanomaterial showed a high mesoporosity due to the surface-layered <I>m</I>SiO<SUB>2</SUB>, and excellent magnetic properties, including magnetic resonance imaging in vitro and in vivo. The mesoporous and magnetic hybrid nanocarriers showed high loading capacity for therapeutic molecules including drug gentamicin and protein cytochrome C. In particular, genetic molecule siRNA was effectively loaded and then released over a period of days to a week. Furthermore, the hybrid nanocarriers exhibited a high cell uptake rate through magnetism, while eliciting favorable biological efficacy within the cells. This novel hybrid multifunctional nanocarrier may be potentially applicable as drug delivery and imaging systems.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2014/aamick.2014.6.issue-4/am4056936/production/images/medium/am-2013-056936_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/am4056936'>ACS Electronic Supporting Info</A></P>

Flavobacterium panacis sp. nov., isolated from rhizosphere of Panax ginseng

Kim, D. H.,Singh, P.,Farh, M. E.,Kim, Y. J.,Nguyen, N. L.,Lee, H. A.,Yang, D. C. Springer Science + Business Media 2016 Antonie van Leeuwenhoek Vol.109 No.9

<P>A novel bacterial strain, designated DCY106(T), was isolated from soil collected from the rhizosphere of ginseng (Panax ginseng), in Gochang, Republic of Korea. Strain DCY106(T) is Gram-negative, yellow-pigmented, non-flagellate, motile, non-spore-forming, rod-shaped, and strictly aerobic. The strain grows optimally at 25-30 degrees C and pH 6.5-7.5. Phylogenetically, strain DCY106(T) is closely related to Flavobacterium arsenitoxidans KCTC 22507(T) (98.41 %), followed by Flavobacterium cutihirudini LMG 26922(T) (97.67 %), Flavobacterium nitrogenifigens LMG 28694(T) (97.59 %), Flexibacter auranticus LMG 3987(T) (97.38 %), Flavobacterium defluvi KCTC 12612(T) (97.21 %) and Flavobacterium chilense LMG 26360(T) (97.05 %). The 16S rRNA gene sequence similarities to all other Flavobacterium species were below97 %. The DNAG+C content of strain DCY106(T) is 34.2 mol% and the DNA-DNA relatedness between strain DCY106(T) and F. cutihirudini LMG 26922(T), F. auranticus LMG 3987(T), F. defluvi KCTC 12612(T) and F. chilense LMG 26360(T) were below 40.0 %. The menaquinone of the type MK-6 was found to be the predominant respiratory quinone. The major polar lipids were identified as phosphatidylethanolamine, phosphatidylserine, two unidentified aminolipids (APL1, APL6) and one unidentified lipid L2.C-15:0, iso-C-15:0 and summed feature 3 (iso-C-15:0 2OH/C-16:1 omega 7c) were identified as the major fatty acids present in DCY106(T). The results of physiological and biochemical tests allowed strain DCY106(T) to be differentiated phenotypically from other recognized species belonging to the genus Flavobacterium. Therefore, it is suggested that the newly isolated organism represents a novel species, for which the name Flavobacterium panacis sp. nov. is proposed with the type strain designated as DCY106(T) (= JCM 31468(T) = KCTC 42747(T)).</P>

Metabolomics for empirical delineation of the traditional Korean fermented foods and beverages

Singh, D.,Lee, S.,Lee, C.H. Elsevier Trends Journals 2017 Trends in food science & technology Vol.61 No.-

<P>Key findings and conclusions: This review outlines the metabolomic perspectives for the traditional Korean fermented foods and beverages. We discuss the current trends towards the application of metabolomics and related methodologies to probe their metabolite contents and functionality. Moreover, the crucial bottlenecks associated with fermentative bioprocess and microbial transformations are also addressed in the context of artisanal and industrial manufacturing processes. Further, the article proposes a rational metabolomic approach towards the discernment of palatability and insalubrities associated with fermented foods. (C) 2017 Elsevier Ltd. All rights reserved.</P>

Extracellular synthesis of silver and gold nanoparticles by Sporosarcina koreensis DC4 and their biological applications

Singh, P.,Singh, H.,Kim, Y.J.,Mathiyalagan, R.,Wang, C.,Yang, D.C. IPC Science and Technology Press ; Elsevier Scienc 2016 Enzyme and microbial technology Vol.86 No.-

<P>The present-study highlights the microbial synthesis of silver and gold nanoparticles by Sporosarcina koreensis DC4 strain, in an efficient way. The synthesized nanoparticles were characterized by ultraviolet visible spectrophotometry, which displayed maximum absorbance at 424 nm and 531 nm for silver and gold nanoparticles, respectively. The spherical shape of nanoparticles was characterized by field emission transmission electron microscopy. The energy dispersive X-ray spectroscopy and elemental mapping were displayed the purity and maximum elemental distribution of silver and gold elements in the respective nanoproducts. The X-ray diffraction spectroscopy results demonstrate the crystalline nature of synthesized nanoparticles. The particle size analysis demonstrate the nanoparticles distribution with respect to intensity, volume and number of nanoparticles. For biological applications, the silver nanoparticles have been explored in terms of MIC and MBC against pathogenic microorganisms such as Vibrio parahaemolyticus, Escherichia coli, Salmonella enterica, Bacillus anthracis, Bacillus cereus and Staphylococcus aureus. Moreover, the silver nanoparticles in combination with commercial antibiotics, such as vancomycin, rifampicin, oleandomycin, penicillin G, novobiocin, and lincomycin have been explored for the enhancement of antibacterial activity and the obtained results showed that 3 mu g concentration of silver nanoparticles sufficiently enhance the antimicrobial efficacy of commercial antibiotics against pathogenic microorganism. Furthermore, the silver nanoparticles potential has been reconnoitered for the biofilm inhibition by S. aureus, Pseudomonas aeruginosa and E. coli and the results revealed sufficient activity at 6 mu g concentration. In addition, gold nanoparticles have been applied for catalytic activity, for the reduction of 4-nitrophenol to 4-aminophenol using sodium borohydride and positive results were attained. (C) 2016 Elsevier Inc. All rights reserved.</P>

Detection of the mycotoxin citrinin using silver substrates and Raman spectroscopy

Singh, D.K.,Ganbold, E.O.,Cho, E.M.,Cho, K.H.,Kim, D.,Choo, J.,Kim, S.,Lee, C.M.,Yang, S.I.,Joo, S.W. Elsevier Scientific Pub. Co 2014 Journal of hazardous materials Vol.265 No.-

We detected a trace amount of the mycotoxin citrinin using surface-enhanced Raman scattering (SERS) on silver nanoparticle (Ag NP) surfaces. The SERS substrate on hydrophobic Teflon films was also introduced to observe the citrinin peaks. A broad band at ~1382cm<SUP>-1</SUP>, which was ascribed to the symmetric carboxylate stretching mode, was observed in addition to an antisymmetric carboxylate stretching mode at ~1568cm<SUP>-1</SUP> in the Raman spectra. The spectral feature indicated that citrinin would adsorb on Ag NPs via its carboxylate form. Based on density functional theory (DFT) calculations, vibrational mode analysis was performed to compare the Raman spectra of citrinin. DFT calculations also predicted that a bidentate bridge configuration through O15 and O16 atoms in citrinin would be the most stable on three Ag atoms. After treating with Ag NPs, observation of citrinin peaks was attempted in fungal cells of Penicillium citrinum. This work may provide useful insights into the direct observation of the hazardous citrinin mycotoxin using SERS by understanding its adsorption behaviors on Ag surfaces.