• Molecules and Cells
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• v.27 no.1
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• pp.83-88
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• 2009

Amino acid homology analysis predicted that rbmD, a putative glycosyltransferase from Streptomyces ribosidificus ATCC 21294, has the highest homology with neoD in neomycin biosynthesis. S. fradiae BS1, in which the production of neomycin was abolished, was generated by disruption of the neoD gene in the neomycin producer S. fradiae. The restoration of neomycin by self complementation suggested that there was no polar effect in the mutant. In addition, S. fradiae BS6 was created with complementation by rbmD in S. fradiae BS1, and secondary metabolite analysis by ESI/MS, LC/MS and MS/MS showed the restoration of neomycin production in S. fradiae BS6. These gene inactivation and complementation studies suggested that, like neoD, rbmD functions as a 2-N-acetlyglucosaminyltransferase and demonstrated the potential for the generation of novel aminoglycoside antibiotics using glycosyltransferases in vivo.

• Korean Journal of Veterinary Research
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• v.48 no.2
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• pp.175-179
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• 2008

Parallux, a solid-phase fluorescence immunoassay (SPFIA) developed for detection antibiotics residue in milk, was applied for analysis of antibiotics in muscle tissue of olive flounder (Paralichthys olivaceus), rockfish (Sebastes schlegeli), and red sea bream (Pagrus major). Fishes were dipped in neomycin 140 mg/ton water, the recommended therapeutic dose, for 24 h. Muscle samples were obtained on 1st, 2nd, 3rd, 4th and 5th day after drug treatment. The concentration of neomycin in muscle was determined using an internal standard (100 ppb as neomycin). The absorbance ratio of sample to internal standard (S/C) was employed as an index to determine the muscle residues in fishes. To investigate the recovery rate, the standard solutions were added to muscle samples to give final concentrations in muscle of 0.2 and 0.5 mg/ml. The recovery rates of all spiked samples were > 85% of the spiked value. Neomycin was detected in muscles of fishes treated after the 1st day of withdrawal period. On the 2nd day after drug treatment, all muscle samples showed negative reaction (S/C ration ${\leq}$ 1.0). The present study showed that the SPFIA can be applied for predicting residues of neomycin in muscle tissues of farmed fishes.

• KSBB Journal
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• v.6 no.1
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• pp.69-77
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• 1991

When S. fradiae was cultured in S medium, it stavted to produce neomycin in the middle of stationary phase of growth. Antibitoic production is regulated not only by glucose but also by metabolites formed from glucose. A chemically defined minimal salt broth was developen for the study of metabolites activating produition of antibiotic in a neomycin producer. When growth and production or antibiotic in minimal salt broth was examined with a full grown or a vefctativc mycelium, the medium was found not to be good for the growth, but to be good enough for the production of antibiotic with a full grown mycelium. When many carbotlydrates, organic acids, or alcohol were supplmented with instead of glucose in the medium suspcndcn with a full grown mycelium, the amount of antibiotic produced in the medium containing fumaratc was 5 times more than that in the medium with glucose. Further study indicated that the medium is not good also for the growth but good for the production of antibiotic. The antibiotic produced in this medium was identified to be neomycin. The activation of the production of neomycin by fumarate was further confirmed in a complex medium. Fuinarate is suspected to initiate and to activate the biosynthesis of neomycin at the gene level.

• Journal of Veterinary Clinics
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• v.6 no.2
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• pp.319-327
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• 1989

In order to study the effects of neomycin sulfate on the kidney of Korean black goats after dosing at 36mg/kg(A group) or 18mg/kg of body weight (B group) twice a day, serum chemical values(BUN, SCr), urinary enzyme(GGT) excretion and urinary analysis were checked and renal lesions were observed by light microscope. The proteinuria and granular casts were observed on the 5-6th day and 7th day of treatment with neomycin respectively in the A group. While these changes were observed on the 4th day and the 6th day respectively in one goat of the B group. Urinary GGT excretion began to increase from the 9th day and reached to maximum concentration on the 15th day of treatment with neomycin in the A group. Thereafter, GGT excretion began to decrease and reach to normal level on the 21th day. But GGT excretion increased on the 9th day in only one goat of the B group. Concentrations of BUN and SCr increased on the 12th day in the A group and in one goat of B group. The kidneys were swollen gross pathologically and the renal tubular epithelial cell changes were noticed histologically in the A group and in one goat of the B group. These changes were included degeneration with hyaline droplet formation, flattened epithelial cells and necrotic epithelium. Granular casts were showed in many tubular lumens. Prfesent results indicated that nephrotoxicosis would not occured in Korean black goats dosing with neomycin sulfate less that 36mg/kg of body weight a day.

• Journal of Pharmaceutical Investigation
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• v.36 no.6
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• pp.371-375
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• 2006

Neomycin coupled to a polymer matrix via a metal linker was prepared and evaluated for prolonging antibacterial activity. Microcrystallized cellulose was chemically modified to cellulose xanthate(MCX) to afford metal binding sites. MCX was treated with Cu(II), Fe(III) or Zn(II) followed by reaction with neomycin (Ne). The release of Ne from MCX-Zn(II)-Ne was investigated and its activity duration was measured by ditch plate method. The amount of metal bound to MCX was 0.36 mmol/g matrix, 0.26 mmol/g matrix and 0.56 mmol/g matrix for Cu(II), Zn(II) and Fe(III), respectively. Ne bound to MCX-metal chelates was 0.006 mmol, 0.07 mmol and 0.01 mmol per g MCX for Cu(II), Zn(II) and Fe(III), respectively. The Ne release from MCX-Zn(II)-Ne was sustained even after seven washes, whereas Ne from MC/Zn(II)/Ne mixture was almost completely released in two washes. Antibacterial activity was prolonged with MCX-Zn(II)-Ne and MCX-Fe(III)-Ne, but not with MCX-Cu(II)-Ne when compared with that of free Ne. Taken together, these results suggest that neomycin coupled to MCX via a proper metal linker has a potential as a polymeric antibacterial agent with sustained activity.

• Bulletin of the Korean Chemical Society
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• v.15 no.7
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• pp.568-571
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• 1994

Streptmyces fradiae NRRL B1195 and Streptomyces kanamyceticus IFO 13414 are highly resistant to the antibiotics they produce. The ribosomes of these organisms are found to be susceptible to the antibiotics, but the cell free extract of S fradiae is found to contain a phosphotransferase and an acetyltransferase which inactivate kanamycin and neomycin, and that of S. kanamyceticus an acetyltransferse which inactivates kanamycin and neomycin. The resistance of these organisms against streptomycin is found to be due to the resistant ribosomes; actually streptomycin activates their ribosomal systems for the synthesis of polyphenylalanine.

• Bulletin of the Korean Chemical Society
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• v.12 no.5
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• pp.504-509
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• 1991

S. fradiae showed very high activity of isocitrate dehydrogenase compared to other microorganisms. The activity of this enzyme was increased with the growth of the organism. But the increase might not imply its involvement in the growth. Rather its increased activity seemed to have a connection with the biosynthesis of neomycin. The enzyme showed high specificity toward $NADP^+$ and D-isocitrate with Km values of 5.75 and 6.74 uM, respectively, It was activated by $Mn^{2+}$. Its molecular weight was estimated from its gel retardation coefficient to be in the range of 61,000-63,000 daltons and its optimum pH was 8.0. The enzyme was thermally unstable.

• Analytical Science and Technology
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• v.22 no.4
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• pp.319-325
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• 2009

An effective and specific procedure for confirmation of neomycin, aminoglycoside antibiotic in honey was developed and validated. Honey was adjusted to pH 2 with 0.1M HCl and applied to weak cation-exchange SPE cartridge. Neomycin was eluted with basified methanol. Following separation by ion-pairing liquid chromatography, neomycin was analysed with positive electrospray ionization and MRM mode. Quantification was linear over the range of $5.0{\sim}250.0{\mu}g/kg$ ($r^2$ >0.9951). The precision (R.S.D.) and accuracy (as a bias) of quality control samples in honey ranged 11.5~18.7% and 10.9~20.9%, respectively. Established method can be applied to analysis of neomycin in honey.

• Journal of Veterinary Clinics
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• v.6 no.2
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• pp.261-268
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• 1989

In order to study the effects of administration of neomycin on the kidney of Korean black goats, 4.5(group A), 9(group B) or 14(group C) mg/kg, body weight of neomycin was injected intramuscularly turice a day for 84 days. On day 31, unilateral nephreotomy was performed in one animal of each group. The results were as follows: Serum neomycin concentrations were 8.7, 13.8, and 20.2 ${\mu}$g/ml 12 hours after injection. Serum BUN and creatinine concentration in nephreotomized goats, regardless of dosage, rapidly increased and came to peak on 3 days after, and then began to decrease to normal range, gradually, In non-nephrectomized goats, regardless of dosage, there was no notable change. In nephreotomized goats, PSP Tl/2 was delayed to the utmost 1 day after nephrectomy, regard-less of dosage, and then began to decrease to normal range, gradually in non-nephrectomized goats, there was not notable change in PSP T$\frac{1}{2}$. The intact kidney was markedly enlarged compared with the kidney of non-nephrectomized goats, but there was no microscopic change. It is concluded that administration of neomycin up to 14mg/kg body weight twice a day for 84 days was not nephrotoxic to the Korean black goats.

• Korean Journal of Medicinal Crop Science
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• v.14 no.6
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• pp.336-341
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• 2006

The endophytic bacteria were isolated from the rusty-root ginseng. This isolated bacteria were occurred the rusty-root ginseng with artificial inoculation. For the suppressing of rusty-ginseng, disinfectants, antibiotics, kitosan, micro-organisms and metabolites were tested to isolated endophytic bacterium. All of the isolated bacteria strains were sensitive sodium hypochlorite, however, some of isolated bacteria lines were sensitive to other tested materials. For example, D (didecyl dimethyl ammonium bromide), CIO$_2$, ODDA (octyldecyl dimethyl ammonium chloride + diocyul dimethyl ammonium chloride + alkyl diethyl benzyl ammonium chloride), GD (glutaraldehyde + dimethy cocobenzyl ammonium chloride) suppressed some of bacteria strains. Otherwise, some of antibiotics (e.g. ampicillin, chloramphenicol, erythromycin, kanamycin, neomycin, rifampin, streptomycin, tetracycline) were sensitive to the isolated bacteria strains. All of isolated bacteria strainswere inhibitive to the mixed formation with neomycin and streptomycin, and neomycin and tetracycline. Both sodium hypochlorite and antibiotic mixing of neomycin and tetracycline were effective to prevention of rusty-root ginseng of sub-merging ginseng in the ginseng field.