• Journal of Microbiology and Biotechnology
• /
• v.20 no.1
• /
• pp.202-207
• /
• 2010

Plant growth promoting fungi (PGPF) are well known for the production of useful secondary metabolites. However, limited information is available on the gibberellin (GA) production capacity of PGPF of endophytic origin. In the current study, 15 fungal endophytes were isolated from the roots of Crown daisy, and then screened on Waito-c rice, in order to identify plant growth promoting fungi. The fungal isolate MH7 significantly increased the shoot length (12.1 cm) of Waito-c in comparison with control treatment (7.9 cm). In a separate experiment, the culture filtrate (CF) of MH7 significantly promoted the growth attributes of Crown daisy. The MH7 CF was analyzed for gibberellins and it contained all physiologically active gibberellins ($GA_1$, 1.37 ng/ml; $GA_3$, 5.88 ng/ml; $GA_4$, 8.62 ng/ml; and $GA_7$, 2.05 ng/ml) in conjunction with physiologically inactive $GA_9$ (0.83 ng/ml), $GA_{12}$ (0.44 ng/ml), $GA_{15}$ (0.74 ng/ml), $GA_{19}$ (1.16 ng/ml), and $GA_{20}$ (0.98 ng/ml). The CF of MH7 produced higher amounts of $GA_3$, $GA_4$, $GA_7$, $GA_9$, and $GA_{12}$ than wild-type Fusarium fujikuroi, which was used as a control for GA production. The fungal isolate MH7 was later identified as a new strain of Penicillium on the basis of its morphological characteristics and phylogenetic analysis of the 188 rDNA sequence.

• Journal of Microbiology and Biotechnology
• /
• v.23 no.8
• /
• pp.1047-1054
• /
• 2013

Witches' broom of lime is a disease caused by Candidatus Phytoplasma aurantifolia, which represents the most significant global threat to the production of lime trees (Citrus aurantifolia). Conventional disease management strategies have shown little success, and new approaches based on genetic engineering need to be considered. The expression of recombinant antibodies and fragments thereof in plant cells is a powerful approach that can be used to suppress plant pathogens. We have developed a single-chain variable fragment antibody (scFvIMP6) against the immunodominant membrane protein (IMP) of witches' broom phytoplasma and expressed it in different plant cell compartments. We isolated scFvIMP6 from a naïve scFv phage display library and expressed it in bacteria to demonstrate its binding activity against both recombinant IMP and intact phytoplasma cells. The expression of scFvIMP6 in plants was evaluated by transferring the scFvIMP6 cDNA to plant expression vectors featuring constitutive or phloem specific promoters in cassettes with or without secretion signals, therefore causing the protein to accumulate either in the cytosol or apoplast. All constructs were transiently expressed in Nicotiana benthamiana by agroinfiltration, and antibodies of the anticipated size were detected by immunoblotting. Plant-derived scFvIMP6 was purified by affinity chromatography, and specific binding to recombinant IMP was demonstrated by enzyme-linked immunosorbent assay. Our results indicate that scFvIMP6 binds with high activity and can be used for the detection of Ca. Phytoplasma aurantifolia and is also a suitable candidate for stable expression in lime trees to suppress witches' broom of lime.

• Journal of Microbiology and Biotechnology
• /
• v.28 no.9
• /
• pp.1517-1526
• /
• 2018

Investigating bacterial diversity and its metabolic capabilities is crucial for interpreting the ecological patterns in a desert environment and assessing the presence of exploitable microbial resources. In this study, we evaluated the spatial heterogeneity of physicochemical parameters, soil bacterial diversity and metabolic adaptation at meter scale. Soil samples were collected from two quadrats of a desert (Thar Desert, India) with a hot, arid climate, very little rainfall and extreme temperatures. Analysis of physico-chemical parameters and subsequent variance analysis (p-values < 0.05) revealed that sulfate, potassium and magnesium ions were the most variable between the quadrats. Microbial diversity of the two quadrats was studied using Illumina bar-coded sequencing by targeting V3-V4 regions of 16S rDNA. As for the results, 702504 high-quality sequence reads, assigned to 173 operational taxonomic units (OTUs) at species level, were examined. The most abundant phyla in both quadrats were Actinobacteria (38.72%), Proteobacteria (32.94%), and Acidobacteria (9.24%). At genus level, Gaiella represented highest prevalence, followed by Streptomyces, Solirubrobacter, Aciditerrimonas, Geminicoccus, Geodermatophilus, Microvirga, and Rubrobacter. Between the quadrats, significant difference (p-values < 0.05) was found in the abundance of Aciditerrimonas, Geodermatophilus, Geminicoccus, Ilumatobacter, Marmoricola, Nakamurella, and Solirubrobacter. Metabolic functional mapping revealed diverse biological activities, and was significantly correlated with physicochemical parameters. The results revealed spatial variation of ions, microbial abundance and functional attributes in the studied quadrats, and patchy nature in local scale. Interestingly, abundance of the biotechnologically important phylum Actinobacteria, with large proposition of unclassified species in the desert, suggested that this arid environment is a promising site for bioprospection.

• Journal of Microbiology and Biotechnology
• /
• v.30 no.10
• /
• pp.1543-1551
• /
• 2020

Panax ginseng has a wide range of activities including a neuroprotective effect, skin protective effects, enhanced DNA repairing, anti-diabetic activity, and protective effects against vascular inflammation. In the present study, we sought to discover the inhibitory effects of a mixture of natural products containing Panax ginseng, Ziziphus jujube, Rubi fructus, Artemisiae asiaticae and Scutellaria baicalensis (PZRAS) on osteoclastogenesis and bone remodeling, as neither the effects of a mixture containing Panax ginseng extract, nor its molecular mechanism on bone inflammation, have been clarified yet. PZRAS upregulated the levels of catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GSH-R) and glutathione peroxidase (GSH-Px) and reduced malondialdehyde (MDA) in LPS-treated RAW264.7 cells. Moreover, treatment with PZRAS decreased the production of IL-1β and TNF-α. PZRAS also inhibited osteoclast differentiation through inhibiting osteoclastspecific genes like MMP-2, 9, cathepsin K, and TRAP in RANKL-treated RAW264.7 cells. Additionally, PZRAS has inhibitory functions on the RANKL-stimulated activation of ERK and JNK, which lead to a decrease in the expression of NFATc1 and c-Fos. In an in vivo study, bone resorption induced by LPS was recovered by treatment with PZRAS in bone volume per tissue volume (BV/TV) compared to control. Furthermore, the ratio of eroded bone surface of femurs was significantly increased in LPS-treated mice compared to vehicle group, but this ratio was significantly reversed in PZRAS-treated mice. These results suggest that PZRAS could prevent or treat disorders with abnormal bone loss.

• The Korean Journal of Mycology
• /
• v.46 no.3
• /
• pp.315-323
• /
• 2018

The goal of this study was to isolate wild yeasts from the fields of medicinal plants and investigate its tyrosinase inhibitory activities. Wild yeasts isolated from soil in the ginseng and Korean angelica fields of Geumsan, Chungcheongnam-do, Korea were identified by comparing the nucleotide sequences of the D1/D2 domain of 26S rDNA. In total, 43 yeast strains belonging to 21 species were isolated from 50 soil samples obtained from two medicinal plant fields. From the ginseng field, six strains of Rhodotorula glutinis and four strains of Sampaiozyma ingeniosa were isolated, out of which Rhodotorula glutinis strains were dominant. In the Korean angelica field, six strains of Cyberlindnera saturnus, three strains of Piskurozyma taiwanensis, and three strains of Saitozyma podzolica were isolated, out of which Cyberlindnera saturnus strains were dominant. We prepared cell-free extracts of the isolated wild yeasts and their tyrosinase inhibitory activities were investigated. Among 43 yeast strains, cell-free extracts of Naganishia globosa G1-7 showed the highest tyrosinase inhibitory activity (28.0%).

• Advances in Traditional Medicine
• /
• v.4 no.3
• /
• pp.171-178
• /
• 2004

Ginseng radix, the root of Panax ginseng C. A. Meyer (Araliaceae), is a medicinal plant used world-widely and has been reported to have various biological effects. To investigate the effects of Ginseng radix on HL-60 cell apoptosis, MTT assay, DNA fragmentation assay and flow cytometry were performed on HL-60 cells. Cells were treated with Ginseng radix at different concentrations $(10^{-4},\;10^{-3}\;and\;10^{-2};\;dilution\;rate)$. Ginseng radix significantly induced cells apoptosis with a time- and dose-dependent manner. To determine whether Ginseng radix-induced apoptosis is due to increase of tumor necrosis factor $(TNF-{\alpha})$ secretion, enzyme-linked immunosorbent assay was performed on HL-60 cells. Unexpectedly, Ginseng radix $(96\;{\pm}\;5\;pg/ml)$ significantly decreased the $TNF-{\alpha}$ secretion compared with control $(174\;{\pm}\;14\;pg/ml)$. Furthermore, Ginseng radix with $rIFN-{\gamma}$ synergistically increased nitric oxide production in mouse peritoneal macrophages. Taken together, our data indicate that Ginseng radix induce apoptosis on HL-60 cells without increase of $TNF-{\alpha}$ secretion and could be used for a supplementary remedy of cancer.

• KSBB Journal
• /
• v.26 no.1
• /
• pp.41-48
• /
• 2011

To enhance cyclo-His-Pro (CHP) content, soybean hydrolysate was obtained using the strains isolated from Chungkukjang and further purified by various purification steps. First, twenty two strains were screened from Chungkukjang containing high level of CHP. Among them, the strain No. 12, which showed higher productivity of CHP from soybean ferment and have homologous sequence with 16S rDNA of Bacillus amyloliquefaciens, was named B. amyloliquefaciens CHP-12. Through various purification processes, CHP was concentrated from soybean ferment using ultrafiltration, which showed the best efficiency of CHP production, with the yield (71.3%) and CHP content (2.14 mg/g). Moreover, when glucose tolerance test was performed in Type I Sprague-Dawley rat induced by streptozotocin using the soybean ferments [0.5 g soybean ferment/kg body weight (CHP-0.5 group)] and 1.0 g soybean ferment/kg body weight (CHP-1.0 group), there were significant differences in glucose levels between diabetes-control group (265.3 mg/dL) and soybean ferment-treated groups (CHP-0.5 group: 84.3 mg/dL and CHP-1.0 group: 85.3 mg/dL) 120 min after glucose injection (2 g/kg body weight) (p < 0.05). Accordingly, it is suggested that the soybean ferment containing high level of CHP might be a candidate material as an anti-diabetic supplement for manufacturing functional healthy foods.

• 한국생물공학회:학술대회논문집
• /
• 2005.10a
• /
• pp.450-455
• /
• 2005

To treat wastewater efficiently by a one-step process of nitrogen removal, a new strain of $N_2-producing$ bacteria from $NH{_4}{^+}$ under an aerobic condition was isolated and identified. By 16S-rDNA analysis, the isolate was identified as Enterobacter asburiae with 96% similarity. The isolate shows that the capacity of $N_2$ production under an oxic condition was approximately three times higher than that under an anoxic condition. The optimal conditions (pH, temperature and C/N ratio) of the immobilized isolate for $N_2$ production were found to be 7.0, $30^{\circ}C$ and 5, respectively. Under all the optimum reaction conditions, the removal efficiency of $COD_{Cr}$ and TN reached 56.1 and 60.9%, respectively. The removal rates of $COD_{Cr}$ and TN were highest for the first 2.5 hrs (with the removal $COD_{Cr}$ ratios of 32.1), and afterwards the rates decreased as reaction proceeded. For application of the immobilized isolate to a practical process of ammonium removal, a continuous bioreactor system exhibited a satisfactory performance at HRT of 12.1 hr, in which the effluent concentrations of $NH{_4}{^+}-N$ was measured to be 15.4 mg/L with its removal efficiency of 56.0%. The maximum removal rate of $NH{_4}{^+}-N$ reached 1.6 mg $NH{_4}{^+}-N/L/hr$ at HRT of 12.1 hr (with N loading rate of 0.08 $Kg-N/m^3-carrier/d)$. As a result, the application of the immobilized isolate appears a viable alternative to the nitrification-denitrification processes.

• Proceedings of the Korean Aquaculture Society Conference
• /
• 2004.05a
• /
• pp.513-513
• /
• 2004

Manila clam, Ruditapes philippinarum, is commercially and ecologically important marine bivalve in Korea and japan. However, clam landings in the two countries have dramatically declined since the 1980-1990's. In the present study, the protozoan parasite, Perkinsus sp., lectin (host's defense-related glycoprotein) and histopathological features were investigated in Manila clams collected from Gomso Bay in Korea and Ariake Bay in japan (one of the largest clam beds in each country) during summer and fall, 2002-2003. DNA sequences of non-transcribe spacer (NTS), internal transcribed space. (ITS) and 5.85 rRNA of Perkinsus sp. were identical to those of P. atlanticus that was reported in Europe and Korea. For diagnosis of Perkinsus, the fluid thioglycollate medium (FTM) and the 2 M NaOH lysis methods were used. Prevalence of the parasite varied from 92.5-98.7% in Gomso Bay and 35.5-37.9% in Ariake Bay. Infection intensity, in terms of the number of Perkinsuscells per gram tissue wet weight, in the clams of Gomso Bay in fall 2002 averaged 1,010,077-470,937 recording approximately100 times higher than that of Ariake Bay, and these were twice higher than those of summer samples in each location. Mean hemagglutination titer of the clams from Gomso Bay was approximately 60-folds higher than that of clams from Ariake Bay in 2002. In histological preparation of the clams from Gomso Bay in 2002, trophozoites of P. atlanticus were in groups and resulted in severe inflammatory response of host clam. Prevalence of the trematod, Cercaria tapes-like in the clams of Gomso Bay and Ariake Bay were 8.8 % and 10.5% respectively. In conclusion, the clams from Gomso Bay showed more severe pathologic symptoms and higher immune response than those of the clams from Ariake Bay.

• BMB Reports
• /
• v.35 no.4
• /
• pp.389-394
• /
• 2002

$[Ru(bpy)_2(dppz)]^2+$ (bpy=2,2'-bipyfidine, dppz=dipyrido[3,2-a:2',3'-c]phenazine) (RuBD), a long-lifetime metal-ligand complex, displays favorable photophysical properties. These include long lifetime, polarized emission, but no significant fluorescence from the complex that is not bound to DNA. To show the usefulness of this luminophore (RuBD) for probing the bending and torsional dynamics of nucleic acids, its intensity and anisotropy decays when intercalated into supercoiled and relaxed pTZ18U plasmids were examined using frequency-domain fluorometry with a blue light-emitting diode (LED) as the modulated light source. The mean lifetimes for the supercoiled plasmids (< $\tau$ >=148 ns) were somewhat shorter than those for the relaxed plasmids (< $\tau$ >=160 ns). This suggests that the relaxed plasmids were shielded more efficiently from water. The anisotropy decay data also showed somewhat shorter slow rotational correlation times for supercoiled plasmids (288 ns) than for the relaxed plasmids (355 ns). The presence of two rotational correlation times suggests that RuBD reveals both the bending and torsional motions of the plasmids. These results indicate that RuBD can be useful for studying both the bending and torsional dynamics of mucleic acids.