• Journal of Microbiology and Biotechnology
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• v.24 no.2
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• pp.177-187
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• 2014

Microbial phytases are enzymes with biotechnological interest for the feed industry. In this article, the effect of spray-drying conditions on the stability and activity of extracellular phytase produced by R. microsporus var. microsporus biofilm is described. The phytase was spray-dried in the presence of starch, corn meal (> $150{\mu}m$), soy bean meal (SB), corn meal (< $150{\mu}m$) (CM), and maltodextrin as drying adjuvants. The residual enzyme activity after drying ranged from 10.7% to 60.4%, with SB and CM standing out as stabilizing agents. Water concentration and residual enzyme activity were determined in obtained powders as a function of the drying condition. When exposed to different pH values, the SB and CM products were stable, with residual activity above 50% in the pH range from 4.5 to 8.5 for 60 min. The use of CM as drying adjuvant promoted the best retention of enzymatic activity compared with SB. Spray drying of the R. microsporus var. microsporus phytase using different drying adjuvants showed interesting results, being quite feasible with regards their biotechnological applications, especially for poultry diets.

• Microbiology and Biotechnology Letters
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• v.27 no.4
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• pp.304-310
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• 1999

We have developed a new process for the production of new structure oligosaccharides using the mixed-culture fementation of Lipomyces starkeyi KSM22 and leuconostoc mesenteroides B-512FMCM.L.starkeyi KSM22 produces a novel DXAMase(an enzyme containing both dextranase and amylase activities). It hydrolyzes the soluble starch and dextran. The hydrolyzates were used as acceptors for dextransucrase of L.mesenteroides to synthesize the new oligosaccharides(NOS). In fermentation, as the concentration of sucrose was increased from 9%(w/v) to 15%(w/v), the yields of dextran(sum of dextran I, MW=66kD, and dextran II, MW=21kD) was increased from 12.7% to 42.5%, and NOS was increased from 3.9% to 5.2% of the theoretical, respectively. The NOS of dp(degree of polymerization) 5 and over was increased from 33.1% to 58.3% of the total NOS. The NOS showed heat resistant up to 12$0^{\circ}C$ and was stable at pHs ranged from 2 to 6. The NOS decreased the pH changes in the culture of S. mutans, and also showed inhibitory effects on the growth of S. aureus or S. typhimurium.

• Korean Journal of Agricultural Science
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• v.37 no.3
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• pp.387-392
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• 2010

This studies were carried out to assess fermentation properties of amylase activity and added rice yogurt of Enterococcus faecium KHM-11 isolated from Korean human milk. The amylase activity of Enterococcus faecium KHM-11 was above 23 units. Characterization of carbohydrate fermentation of Enterococcus faecium KHM-11 has D-ribose, D-lactose, L-arabinose and starch. Titratable acidity and viable count of lactic acid bacteria of 4% rice yogurt was higher compared to the 0%. Therefore we were discussed Enterococcus faecium KHM-11 is suitable microorganism for fermented milk added rice powder. Hydrolysates of sugars of fermented milk with 4% rice powder cultured Enterococcus faecium KHM-11 were analyzed by TLC and HPLC. Hydrolysates of lactose and galactose were revealed and hydrolysates of glucose was not revealed in results of TLC and HPLC.

• Journal of Environmental Science International
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• v.22 no.10
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• pp.1353-1361
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• 2013

The objectives of this paper are the characterization of the pretreatment of wastewater by microfiltration (MF) membranes for river maintenance and water recycling. This is done by investigation of the proper coagulation conditions, such as the types and doses of coagulants, mixing conditions (velocity gradients and mixing periods), pH, etc., using jar tests. The effluent water from a pore control fiber (PCF) filter located after the secondary clarifier at Kang-byeon Sewage Treatment Plant (K-STP) was used in these experiments. Two established coagulants, aluminum sulfate (Alum) and poly aluminum chloride (PAC), which are commonly used in sewage treatment plants to treat drinking water, were used in this research. The results indicate that the optimal coagulation velocity gradients (G) and agitation period (T) for both Alum and PAC were 200-250 $s^{-1}$ and 5 min respectively, but the coagulation efficiencies for both Alum and PAC were lower at low values of G and T. For a 60 min filtration period on the MF, the flux efficiencies ($J/J_0$ (%)) at the K-STP effluent that were coagulated by PAC and Alum were 92.9 % and 79.9 %, respectively, under the same coagulation conditions. It is concluded that an enhanced membrane process is possible by effective filtration of effluent at the K-STP using the coagulation-membrane separation process.

• YAKHAK HOEJI
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• v.40 no.6
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• pp.713-719
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• 1996

Identification of soil microorganism strain B-6. a producer of acyl CoA synthetase inhibitor, based on its morphological, physiological, biochemical and chemotaxonomical charact eristics was performed. The strain B-6 was identified as Bacillus subtilis. Ihe acyl CoA synthetase inhibitor produced by this strain was highly achieved in fermentation medium that contained glucose 1.0%, soluble starch 1.0%, NH$_4$Cl 0.3%, oatmeal 1.0%, pharmamedia 1.0%, basic magnesium carbonate 0.5%. pH 7.5 at 30$^{\circ}$C for 7 days. The optimal pH and temperature for growth were 9.0 and 30$^{\circ}$C, respectively. Butanol extract of culture filterate of strain B-6 in acyl CoA synthetase inhibitor production medium containing corn steep liquor exhibited high acyl CoA synthetase inhibitor activity and antimicrobial activity against C. albicans. But chloroform extract of culture filterate of strain B-6 in medium containing NH$_4$Cl, ($NH_4)_2SO_4$ or urea instead of corn steep liquor exhibited higher antimicrobial activity against C. albicans than that of butanol extract.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.1
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• pp.1-13
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• 2015

Feed is single most expensive input in commercial pork production representing more than 50% of the total cost of production. The greatest proportion of this cost is associated with the energy component, thus making energy the most important dietary in terms of cost. For efficient pork production, it is imperative that diets are formulated to accurately match dietary energy supply to requirements for maintenance and productive functions. To achieve this goal, it is critical that the energy value of feeds is precisely determined and that the energy system that best meets the energy needs of a pig is used. Therefore, the present review focuses on dietary supply and needs for pigs and the available energy systems for formulating swine diets with particular emphasis on the net energy system. In addition to providing a more accurate estimate of the energy available to the animal in an ingredient and the subsequent diet, diets formulated using the this system are typically lower in crude protein, which leads to additional benefits in terms of reduced nitrogen excretion and consequent environmental pollution. Furthermore, using the net energy system may reduce diet cost as it allows for increased use of feedstuffs containing fibre in place of feedstuffs containing starch. A brief review of the use of distiller dried grains with solubles in swine diets as an energy source is included.

• Journal of Microbiology and Biotechnology
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• v.9 no.3
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• pp.260-264
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• 1999

The combined activities of dextranase and amylase(DXAMase) from Lipomyces starkeyi KSM 22 produced from starch fermentation inhibited or prevented dental plaque formation. The activities were stable in commercial mouthwash products; DXAMase activity retained over 93％ of original activity after 6 months at 23℃. We examined the effects of enzyme inhibitors and active ingredients in mouthwash on DXAMase activity. The DXAMase was stable with 0.29％(w/v) EDTA, 20％ (v/v) ethanol, 0.05％ (w/v) fluoride, and 0.05％ (w/v) SDS. Among the active ingredients of mouthwash, sodium benzoate (up to 1 ％, w/v) had no inhibitory effect on either dextranase or amylase activity. In the case of cetylpyridinium chloride, the addition of 0.05％ (w/v) inhibited 6％ of dextranase activity and 13％ of amylase activity. Propylene glycol (up to 1％, w/v) showed no inhibitory effect on either enzyme activity. DXAMase (5 IU/㎖) in mouthwash could remove pre-formed films of glucan-bound S. mutans cells. The addition of 0.1 IU/㎖ DXAMase in mouthwash prevented the formation of insoluble-glucan. These in vitro properties of L. starkeyi KSM 22 DXAMase are desirable for its application as a dental plaque control agent.

• Journal of Life Science
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• v.8 no.4
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• pp.387-394
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• 1998

A thermophilic bacterium (strain DG0303) producing a thermostable $\alpha$-glucosidase was isolated from manure and identified as Bacillus sp. Strain DG0303 produced high level of $\alpha$-glucosidase compared with other thermophilic Bacillus strains. The cellular protein patterns were also compared with other Bacillus strains by sodium dodecyl sulfatepolyacrylamide gel electrophoresis(SDS-PAGE). On the basis of 16S rDNA analysis the Bacillus sp. DG0303 was found to be a member of Bacillus rDNA group 5. The optimum temperature for growth was 65$\circ$C and no growth was obtained at 40$\circ$C or 75$\circ$C. The optimum pH for growth was 5.5 to 8.5. $\alpha$-glucosidase activity was produced during growth and most activity was detected in the culture supernatant. The $\alpha$-glucosidase production was constitutive in the absence of carbohydrates. High level of enzyme activity was detected when the culture was grown on medium containing starch. Addition of glucose resulted in the repression of the $\alpha$-glucosidase production. The optimum pH and tempoerature for enzyme activity were pH 5.0 and 65$\circ$C, respectively. When analyzed by zymogram, the culture supernatant showed a single $\alpha$-glucosidase band with a molecular weight of approximately 60,000.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.70-75
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• 2008

Two extracellular amylase isozymes were purified and characterized from alkalophilic Pseudomonas sp. KFCC 10818 for the production of maltooligosaccharides. The molecular weights of the homogeneous proteins were 50 kDa and 75 kDa, respectively. The 50 and 75 kDa amylases showed optimum temperatures at 35 and $40^{\circ}C$, respectively. The optimum pH of the enzymes ranged from pH 6-8, and the enzymes were resistant to an alkaline condition of pH 12. Via the enzyme's actions, the final products from maltooligosaccharides or soluble starch were maltose and maltotriose. Calcium was a potent activator of the 50 kDa amylase. Finally, the N-terminal amino acid sequences of the 50 and 75 kDa amylases were QTVPKTTFV and DTVPGNAFQ, respectively.

• Journal of Applied Biological Chemistry
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• v.42 no.3
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• pp.107-112
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• 1999

A carboxymethyl-cellulase (CMCase) was purified from the culture supernatant of Bacillus sp. KD1014 by ultrafiltration, ammonium sulfate precipitation, and a series of chromatography on QAE-Sephadex A-50, hydroxylapatite and Sephadex G-75. The purified CMCase was a single protein of 32 kDa, showed an optimum activity at $60^{\circ}C$ and pH 6.0, and had a half-life of 23 min at $70^{\circ}C$. The enzyme activity was not influenced by metal ions such as $Mg^{2+},\;Fe^{3+},\;K^+,\;Zn^{2+}$, and $Cu^{2+}$ at a concentration of 1.0 mM, partially inhibited by $Mn^{2+}$ and $Ag^+$, and significantly inhibited by pentachlorophenol (PCP). The purified enzyme showed a 3.9-times higher activity on lichenan than on CMC, but hardly cleaved xylan, starch, avicel, laminarin, filter paper and levan. The results of activity staining of the purified enzyme separated by native and denaturing gel electrophoresis suggested that the CMCase might exist in dimeric, oligomeric or aggregated form as well as in monomeric form. The enzymatic cleavage products from cellotetraose indicated that the CMCase possessed transglycosylation activity.