• Asian-Australasian Journal of Animal Sciences
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• v.30 no.9
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• pp.1278-1284
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• 2017

Objective: To assess the potency of calcium propionate (CAP) used as silage additive, an experiment was carried out to evaluate the effect of CAP on the nitrogen transformation, fermentation quality and aerobic stability of alfalfa silages. Methods: Alfalfa was ensiled with four levels of CAP (5, 10, 15, and 20 g/kg of fresh weight [FW]) in laboratory silos for 30 days. After opening, the silages were analyzed for the chemical and microbiological characteristics, and subjected to an aerobic stability test. Results: The increasing proportion of CAP did not affect pH, lactic acid (LA) concentrations and yeast counts, while linearly decreased counts of enterobacteria (p = 0.029), molds (p<0.001) and clostridia (p<0.001), and concentrations of acetic acid (p<0.001), propionic acid (p<0.001), butyric acid (p<0.001), and ethanol (p = 0.007), and quadratically (p = 0.001) increased lactic acid bacteria counts. With increasing the proportion of CAP, the dry matter (DM) loss (p<0.001), free amino acid N (p<0.001), ammonia N (p = 0.004), and non-protein N (p<0.001) contents were linearly reduced, whereas DM (p = 0.048), water soluble carbohydrate (p<0.001) and peptide N (p<0.001) contents were linearly increased. The highest Flieg's point was found in CAP10 (75.9), represented the best fermentation quality. All silages treated with CAP improved aerobic stability as indicated by increased stable hours compared with control. Conclusion: The addition of CAP can suppress the undesirable microorganisms during ensiling and exposure to air, thereby improving the fermentation quality and aerobic stability as well as retarding the proteolysis of alfalfa silage. It is suggested that CAP used as an additive is recommended at a level of 10 g/kg FW.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.3
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• pp.155-161
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• 2021

This study was conducted to estimate the effect of different cutting lengths on fermentation characteristics and aerobic stability of whole crop rice (WCR) silage. The WCR was harvested at the yellow ripe stage (43.7%, DM), and then cut at 5 (R05), 10 (R10), and 20 cm (R20) of the theoretical length of cut with no cut WCR (R60). Each forage was ensiled into 20 L mini bucket silo (5 kg) for 150 days in quadruplicates. The cutting lengths were not affected the chemical compositions of WCR silage (p > 0.05). The pH (p < 0.001) and concentration of ammonia-N (p = 0.022) in WCR silage were increased linearly with the increase of cutting length. The concentration of lactate had quadratic effect (p = 0.007), which was highest in R20 silage (p < 0.05). The concentration of acetate was increased linearly (p = 0.014), but the concentration of butyrate was decreased linearly (p = 0.033). The lactic acid bacteria count was decreased linearly (p = 0.017), and yeast count had quadratic effect (p = 0.009), which was the highest in R20 silage (p < 0.05). Aerobic stability had strong quadratic effect (p < 0.001), which was the highest in R20 silage (p < 0.05). In conclusion, R60 silage had highest pH by a linear increase of ammonia-N concentration and led to low aerobic stability. While R20 silage had the lowest pH by high lactate concentration and led to high aerobic stability.

• Korean Journal of Food Science and Technology
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• v.22 no.3
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• pp.319-324
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• 1990

The effects of pH, protein and fat content, addition of emulsifiers, stabilizer, sugar, salt and calcium salt on the stability of soymilk suspension were investigated by analyzing the cream separated and precipitates of soymilk which is prepared by various conditions. In the alkaline region of pH, soymilk showed a good stability of the suspension and particularly, above pH 10, precipitates were not formed. When 1.5% of palm oil with 0.4% of glycerine monostearate was added to soymilk in the hydrophile-lipophile balance (HLB) value of 4 to 7, resulted maximal emulsion stability occured below H LB 6. The stability was decreased with increasing the fat concentration and soy oil showed better emulsion stability than that of palm oil. Among the commercial stabilizers, 0.03% of carrageenan was most effective. The stability was not decreased by addition of sugar up to 3% while it was decreased by addition of sodium salt and calcium salt at low level.

• Journal of applied mathematics & informatics
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• v.7 no.3
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• pp.1017-1027
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• 2000

On the positive real number, we obtain the Hyers-Ulam stability and a stability in the sense of R. Ger for the generalized beta function g(x+p,y+q) = ${\varphi}(x,y)g(x,y)$ in the following settings: $$\mid$g(x+p,y+q)-{\varphi}(x,y)g(x,y)$\mid${\leq}{\delta}$ and $$\mid$\frac{g(x+p,y+q)}{\varphi(x,y)g(x,y)}-1$\mid${\leq}{\psi}(x,y). As a consequence we obtain stability theorems for the gamma functional equation and the beta functional equation.

• Biomolecules & Therapeutics
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• v.1 no.1
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• pp.31-36
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• 1993

To evaluate the feasibility of transmucosal delivery of methionine enkephalin analog, [$D-Ala^2$]-me-thionine enkephalinamide (YAGFM), the influence of pH, temperature, ionic strength and initial peptide concentration on the physicochemical stability of YAGFM in aqueous buffered solutions were investigated using a stability-indicating HPLC method. The degradation of YAGFM followed the pseudo-first-order kinetics. From the pH-rate profile, the maximum stability of YAGFM was shown to be at the pH of about 5.0. The halflife for the degradation of YAGFM was found to be 181.3 days at pH 5.0 and $37^{\circ}C.$ Arrhenius plots of the data obtained at 25~$45^{\circ}C$ were reasonably linear with a correlation coefficient greater than 0.99, and the activation energy was calculated to be 8.9 kcal/mole. A higher ionic strength and/or a higher peptide concentration in buffered solutions retarded the degradation of YAGFM.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.12
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• pp.1999-2007
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• 2020

Objective: This study was aimed to investigate the muscle-specific beef color stability at normal and high ultimate pHs. Methods: The impact of muscle (Longissimus lumborum [LL] vs psoas major [PM]) and pH (normal ultimate pH [Np] vs high pH dark cutting beef [Hp]) on color stability, indicated by basic color traits, metmyoglobin reducing activity (MRA) and oxygen consumption (OC), as well as the lipid oxidation, were determined over 7 days of display at 4℃. Results: Hp-LL had the highest pH (6.92), followed by Hp-PM (6.01), Np-PM (5.76), and Np-LL (5.52). Hp-LL had increased (p<0.05) a^⋆, chroma and % oxymyoglobin during display. Hp-LL also had the highest metmyoglobin (MMb) reducing activity and OC among all the samples, thus, the greatest color stability, although very dark throughout storage, with lowest values for lightness (L^⋆) and yellowness (b^⋆). Np-LL also exhibited relatively high color stability, as a result of its lower % MMb and OC and higher MRA than psoas muscle samples. The 0.2 unit difference of the pH between Hp and Np psoas muscle, resulted in the difference of the color intensity, not the color stability. Interestingly, high pH psoas muscle (Hp-PM) did not have better color stability than Np-PM, and in fact had lower color stability than even Np-LL. The similar level of OC and lipid oxidation cannot explain the difference in color stability between Hp-PM and Np-LL. Conclusion: The Hp does not always show better color stability compared with Np beef, which depends on the muscle type. The balance of MRA and OC is important to keep the color in great intensity and stability in the meantime.

• Korean journal of food and cookery science
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• v.7 no.2
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• pp.97-104
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• 1991

This study was carried out in order to study the protein functionality such as foaming and emulsifying properties by succinylation of peanut protein isolates. Succinylated and unsuccinylated peanut protein isolate was tested for to find out the effect of pH, heat treatment and sodium chloride concentration on the solubility, foam expansion, foam stability, emulsion capacity and emulsion stability. The results are summarized as follows; 1. Succinylation enhanced the solubility of peanut protein isotate (PPI). The solubility of succinylated PPI markedly increased at pH 4.5. When the protein solutions was heated, the solubility of succinylated PPI greatly increased than PPI at pH 3. With addition of NaCl, solubility of succinylated PPI increased at pH 7 and pH 9. 2. The foam expansion of PPI and succinylated PPI on pH was no difference between both proteins. Addition of NaCl and heat treatment caused steeply increased in foam expansion at pH 3. 3. The foam stability of PPI and succinylated PPI showed the lowest value at pH 4.5. When PPI and succinylated PPI was heated, foam stability of two proteins incensed at pH 3 and showed similar aspects between PPI and succinylated PPI. However, at pH 9 stability of succinylated PPI decreased by heat treatment over $60^{\circ}C$. 4. Emulsion capacity of succinylated PPI on pH was markedly increased and showed the highest value at pH 11. At pH 4.5 which is isoelectric point of PPI, emulsion capacity of PPI by succinylation improved than that of PPI. When succinylated PPI was heated, emulsion capacity was greatly increased at pH 2 and pH 7. With NaCl was added, emulsion capacity of succinylated PPI increased than that of PPI. 5. Emulsion stability of PPI and succinylated PPI was affected by pH and showed its highest value at pH 11. At pH 4.5, emulsion stability of succinylated PPI increased than that of PPI. Addition of NaCl and heat treatment caused slightly increased in emulsion stability of succinylated PPI.

• Journal of Pharmaceutical Investigation
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• v.19 no.4
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• pp.213-217
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• 1989

To formulate the stable preparation of Gingko extract injection and to evaluate the stability of the preparation, Gingko extract aqueous solutions having various pH values were prepared and the stability of ginskoflavonglycoside (GFG) was investlfated by high performance liquid chromatography. The stability of GFG decreased as pH increased, while the water solubility of Gingko extract decreased as pH decreased. The optimal pH of the Gingko extract aqueous solution was found to be pH 6.5. The shelf life $(T_{90%})$ of the Gingko extract aqueous solution of pH 6.5 at $20^{\circ}C$ was extrapolated to be four years.

• Microbiology and Biotechnology Letters
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• v.19 no.5
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• pp.433-438
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• 1991

The plasmid pSY130-14 for the high production of phenylalanine is a temperaturecontrollable expression vector composed of the $P_R$ and the $P_L$ promoter and a temperature sensitive repressor, $cI_{857}$ of bacteriophage lambda. Strain AT2471 harbouring plasmid pSY13O- 14 is induced the phenylalanine production by shifting up the incubation temperaure to $38.5^{\circ}C$. Plasmid stability of E. coli AT2471 harbouring pSY130-14 was very low, it was about 30% after 48 h cultivation at $38.5^{\circ}C$ without kanamycin. The plasmid disappeared immediately at $40^{\circ}C$ without kanamycin, and at $40^{\circ}C$ adding kanamycin, the plasmid stability decreased at the beginning, but rose with the extension of the culture time. For the improvement of plasmid stability, the plasmid obtaind was designated as pSY15O-1 by changing origin region (ori) pACYC 177 of pSY130-14 for ori pSC101. E. coli AT2471 harbouring pSY150-1 was stable at $38.5^{\circ}C$ without tetracycline, and the plasrnid stability was about 40% after 48 h cultivation at $40^{\circ}C$.

• Journal of the Korean Home Economics Association
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• v.28 no.2
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• pp.37-45
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• 1990

The purpose of this study was to determine the foaming properties of two small red bean protein isolates at various conditions. Data concerning the effects of pH, temperature, MaCl concentration, sugar concentration and protein concentration on the properties such as solubility, foam expansion, foam stability were presented. The results were summarized as follows : 1. The crude protein contents of two small red beans were 26.14% and 22.71%. The percentage of nonpolar amino acid group was the highest and that of sulfur containing amino acid group was the lowest. 2. Protein solubility showed the minimum at pH 4.5 which is isoelectric point of small red bean protein isolate adn heat treatment lowered solubility(P<0.05). At pH 4.5, solubility increased sighificantly as 0.4M NaCl was added. However, the effect of sugar concentration in the solubility was not significant. 3. Foam expansion of two small red bean protein isolates was high at pH 4.5 and heat treatment at 10$0^{\circ}C$ lowered foam expansion(P<0.05). While addition of NaCl, sugar did not affect the foma expansion, gradual increment of the protein isolates concentration up to 9% decreased the foma expansion slightly. 4. Foam stability was significantly high at pH 4.5 and heat treatment at 10$0^{\circ}C$ lowered foam stability. Addition of sugar caused slight decrease in foam stability. From 1% to 9% suspension, foma stability increased significantly as protein concentration increased(P<0.05)