• Korean Journal of Food Science and Technology
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• v.53 no.3
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• pp.334-343
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• 2021

Various vegetables, including cucumbers, have a high probability of foodborne illness because they are usually eaten raw. In this study, we analyzed the 16S rRNA gene sequences of the cucumber (Cucumis sativus L.) microbiota. The diversity indices of cucumber cultivated in May were higher than in cucumber cultivated in November. At the phylum level, Proteobacteria, Firmicutes, and Actinobacteria were predominant. The classes generally comprised Gammaproteobacteria, Bacilli, Alphaproteobacteria, and Actinobacteria. At the genus level, the proportions of Aureimonas, Escherichia, and Microbacterium in samples from May were relatively high, whereas Enterococcus, Pseudomonas, and Rhizobium accounted for a higher proportion in samples from November. Moreover, it is noteworthy that potential pathogenic genera such as Acinetobacter, Aerococcus, Aureimonas, Enterobacter, Enterococcus, Escherichia, Pantoea, Pseudomonas, and Staphylococcus were detected. Although further studies on the characteristics of potential pathogens are required, our results can be used to improve the food safety of vegetables.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.480-490
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• 2003

An innovative biopolymer known as the Rhizobian gum has been developed in France, which shows some dramatic refreshing effect on the skin. The origin of this innovative project takes its source in the natural environment, and in particular the natural environment of the roots of sunflowers and wheat, where a symbiotic bacterium has been discovered. It is a Rhizobium bacterium, which is hosted by the roots, and which is able to synthesize a specific polymer showing a dramatic water binding capacity. This polymer is in particular synthesized in period of drought, and its biological role is to concentrate the small amount water present in the soil in order to take it available for the root, which becomes then able to absorb it. This vital mechanism allows the plant to survive despite a severe climatic environment. This basic research has been conducted in collaboration whit the French National centre of scientific Research (CNRS), and has lead to the isolation of the Rhizobium bacteria. Rhizobian gum is a branched biopolymer consisting in the repetition of a polysaccharide unit of 3 molecules of glucose, 3 molecules of galactose and 1 molecule of glucuronic acid, whit one pyruvate group an average 1.6 acetyl groups. The fresh effect of Rhizobian gum is a strong sensorial impact that 100 ％ of the consumers are able to perceive, and which is judged very pleasant by most of them. In addition to this, a large majority of consumers are perceived, and which is judge very pleasant by most of them. In addition to this, a large majority of consumers also feel a very pleasant relaxing sensation. Smoothness and softness are also felt by most consumers and qualified positively by most of them. These qualities guarantee a strong impact on today's consumers.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.50-60
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• 2003

An innovative biopolymer known as the Rhizobian gum has been developed in France, which shows some dramatic refreshing effect on the skin. The origin of this innovative project takes its source in the natural environment, and in particular the natural environment of the roots of sunflowers and wheat, where a symbiotic bacterium has been discovered. It is a Rhizobium bacterium, which is hosted by the roots, and which is able to synthesize a specific polymer showing a dramatic water binding capacity. This polymer is in particular synthesized in period of drought, and its biological role is to concentrate the small amount water present in the soil in order to take it available for the root, which becomes then able to absorb it. This vital mechanism allows the plant to survive despite a severe climatic environment. This basic research has been conducted in collaboration whit the French National centre of scientific Research (CNRS), and has lead to the isolation of the Rhizobium bacteria. Rhizobian gum is a branched biopolymer consisting in the repetition of a polysaccharide unit of 3 molecules of glucose, 3 molecules of galactose and 1 molecule of glucuronic acid, whit one pyruvate group an average 1.6 acetyl groups. The fresh effect of Rhizobian gum is a strong sensorial impact that 100 ％ of the consumers are able to perceive, and which is judged very pleasant by most of them. In addition to this, a large majority of consumers are perceived, and which is judge very pleasant by most of them. In addition to this, a large majority of consumers also feel a very pleasant relaxing sensation. Smoothness and softness are also felt by most consumers and qualified positively by most of them. These qualities guarantee a strong impact on today's consumers.

• Applied Biological Chemistry
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• v.35 no.3
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• pp.179-185
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• 1992

Rhizobium meliloti populated in five Korean pasture soils were characterized by symbiotic effectiveness and intrinsic antibiotic resistance using whole-soil inoculum and 11 antibiotics, respectively. Most probable number (MPN) of naturalized rhizobia counted with alfalfa Vernal[Medicago sativa (L.)] as a host ranged $1.7{\times}10^2\;cells/g$. soil(Chunghyo, Kyeongiu)-$1.0{\times}10^5\;cells/g$. soil(Gampo, Kyeongiu) and ended to be positively associated with soil pH. On the whole, the effectiveness of population as compared to TAL mix inoculum (TAL 380+TAL 1372+TAL 1373) was very low. Nevertheless, there were two highly effective strains, YCK 539 and YCK 542, which were not inferior to TAL 1372, from Ogpo, Dalseong among the total of 30 of 6 isolates per each soil. As long as mean $N_2$ fixing ability of each soil isolate, the isolates from Hyeongog, Kyeonju were outstanding and the rest were in order of Ogpo, Dalseong>Chunghyo, Kyeongju>Hwaweon, Dalseong>Gampo, Kyeongiu. Isolates as a whole were resistant to erythromycin(67崙), nalidixic acid(77%), and streptomycin sulfate(8051), which had the concentration of $100\;{\mu}g/ml$, $160\;{\mu}g/ml$, and $10\;{\mu}g/ml$, respectively and divided into 14 patterns of resistance. Association between resistances in each soil was not clear. And there was no relationship of resistance pattern to effectiveness. The best effective strain YCKa 542 exclusively fell into No. X pattern having resistance to erythromycin, nalidixic acid, and neomycin sulfate.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.2
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• pp.217-220
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• 2002

Mulberry being a foliage crop is grown extensively for feeding of silkworms and are also used for cattle feeding. These loaves are highly nutritious, which contain various mineral elements and bio-molecules such as carbohydrates, proteins, lipids and other essential amino acids, etc. In the present study, deproteinized mulberry leaf juice was used for preparation of the medium for cultivation of various types of microbes. Results revealed that deproteinized mulberry leaf juice medium is best for isolation of fungi, bacteria and actinomycetes and this medium can be substituted with synthetic media, which are haying the costly ingredients for isolation and identification of bacteria, fungi and actinomycetes. Further, this deproteinized mulberry juice medium can also be used in mass multiplication of useful/beneficial microbes to enhance soil microflora to improve soil fertility and to avoid root diseases. Perspective enterprises can take up the mass multiplication/large-scale production of useful microbes such as Trichoderma, Rhizobium, Pseudomonas and Bacillus to use in mulberry and in other agricultural crops using deproteinized mulberry leaf juice.

• Journal of Applied Biological Chemistry
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• v.44 no.3
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• pp.125-130
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• 2001

A putative protein encoded by Arabidopsis AtMTN3 gene, a homologue of Medicago truncatula MTN3, consists of 285 amino acid residues, and has a predicted molecular mass of 31.5 kDa and a calculated pI of 9.1. Primary amino acid sequence analyses have revealed that the protein contains seven putative transmembrane regions with N-terminus oriented to the outside of the membrane. The AtMTN3 protein shows overall 16.4% of amino acid identity with the rat GALR3 protein, known to be a G-protein-coupled receptor. The gene is present as a single copy in the Arabidopsis genome, and expressed in aerial parts but not in roots of Arabidopsis. Therefore, AtMTN3 appears not to be specifically involved in Rhizobium-induced nodule development, as was predicted for the MTN3 gene. These proteins possibly mediate signal transmission through G-protein-coupled pathways during general interactions between plants and symbiotic or pathogenic microbes.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.762-766
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• 2001

The nar promoter of Escherichia coli was known to induce maximally under anaerobic or microaerobic conditions in the presence of nitrate. In this study, the nar promoter was tested to see whether the expression level of a reporter gene which fused lacZ gene at nar promoter's downstream, in the some gram negative host strains(Agrobacterium, Pseudomonas and Rhizobium). A nar promoter system(Combination of nar promoter and gram negative strain) was grown under aerobic conditions to absorbance at 600 nm of nearly 2.0 and then, the nar promoter was induced by lowering DO to 1-2% with alternating microaerobic and aerobic condition in the fermentor cultures, using different gram negative hosts. For a wild type nar promoter (pNW61), it was possible to maintain production of ${\beta}-galactosidase$ activity per cell(specific ${\beta}-galactosidase$ activity) at 14,000, 9600, 45 Miller units in the presence of 1% nitrate. and for a nitrate - independent nar promoter (pNW618) at 12,000, 10,400 and 58 Miller units in the absence of nitrate ion, respectively.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.415-422
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• 1996

A gene coding for a pyruvyl transferase enzyme involved in exopolysaccharide biosynthesis of Zoogloea ramigera 115SLR was isolated and sequenced. A 4.5 kb of BamHI DNA fragment was isolated from chromosomal DNA using a probe derived from ketal pyruvyl transferase gene of Xanthomonas campestris. The nucleotide sequence of 2.66 kb Pst1/HindIII DNA fragment which was homology with a probe revealed the existence of two complete open reading frames (ORF2 and ORF3) and two partial open reading frames (ORFI and ORF4). The deduced amino acid sequence of ORF3 was homologous to the ketalase (GumL product) of X campestris with 49.5% of similarity and 21.6% of identity. ORF2 on the other hand showed the higher identity with the ketalase (ExoV product) of Rhizobium meliloti (36%) as well as the ketalase of X campestris (23%) than that of ORF3. A gene product of ORF2 was determined with a bacteriophage T7 RNA polymerase/promoter system in E. coli. The molecular weight of protein was 33,500 dalton.

• Korean Journal of Environmental Biology
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• v.22 no.4
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• pp.479-486
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• 2004

Phytoestrogens display estrogen-like activity because of their structural similarity to human estrogens and exhibit high affinity binding for the estrogen receptors (ERs). The prevalence of phytoestrogens in our diets and the biological effects that they may cause need to be fully examined. ER is the ancestral receptor from which all other steroid receptors have evolved. Although phytoestrogens serve specific signaling functions between the plants and insects, fungi, and bacteria, many chemical signals are often misinterpreted as estrogenic signals in non-target organisms such as vertebrates. There are no ERs in plants or in their most common partners, insects. However, Rhizobium soil bacteria have NodD proteins which is an intended target of phytoestrogen signaling and share genetic homology with the ER. These two evolutionarily distant receptors both recognize and respond to a shared group of chemical signals and ligands, including both agonists and antagonists. This review briefly summarizes estrogen and estrogen receptors, kinds of important phytoestrogens, their health effects as well as some of the evolutionary aspects of mechanism by which phytoestrogen mimics the endogenous ER signaling in our body.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1338-1342
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• 2004

Cyclosophoraoses (Cys), cyclic ${\beta}-(1{\rightarrow}2)-D-glucans$ produced by Rhizobium meliloti 2011, were used as a novel chiral stationary phase for the enantiomeric separation. A novel Cys stationary phase, chemically immobilized onto porous silica via aminopropyltrimethoxysilane as a molecular linker, showed good separation for each racemate of bupivacain (separation factor, $\alpha$=1.3), propranolol ($\alpha$=1.3), and fenoprofen ($\alpha$=2.9), respectively, under the mobile phase of water: methanol (80:20, v/v) at a constant flow rate of 0.9 ml/min at pH7.