• Korean Journal of Clinical Laboratory Science
• /
• v.49 no.4
• /
• pp.359-365
• /
• 2017

There is greater standardization of quality control for microscopic examination of urine than for physicochemical test. In this study, we investigated whether it is possible to control the sediment accuracy by microscopic examination through the real thing by preserving the essential sediment with glutaraldehyde, which is required for the rationality of sediment quality control. A urine specimen was prepared using 2.5% glutaraldehyde as a preservation solution. Samples treated with urine preservatives confirmed the morphological deformation of the cells for four weeks at intervals of one week and confirmed whether they should be preserved for 4 weeks thereafter. After preparing the required sediment slide, two more slides were produced; one was stored in a refrigerator for, and the other was stored at room temperature. The morphological deformation of the specimen was confirmed. Glutaraldehyde has the effect of preserving the refrigerated essential sediments and storing them for up to 8 weeks, refrigerated storage after slide production, stabilized by 3 days. Moreover, after treatment with preservatives, the production of the slide and comparison between the measured values between the laboratories and examiners showed a low consistency. In conclusion, we showed that the urine sediment components can be preserved, and it can be used for quality control and education through real objects.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.6 no.1_2
• /
• pp.37-43
• /
• 1973

In this paper, non-enzymatic browning reactions as a factor of self stability of boiled and dried anchovy were studied to discuss the effect of water activity to the discoloring reaction and the preservative moisture content. The development of rancidity of the fish meat was also mentioned since the fish is fatty and the lipid oxidation is a functional deteriorative reaction. Fresh anchovies were boiled in $10\%$ salt solution immediately after the catch, sun dried, and stored at room temperature ($20^{\circ}C$) for two months in humidistat chambers maintaining different levels of water activity as described in Table 1. The pigments formed by non-enzymatic browning reations were extracted in two fractions, those were chloroform-methanol soluble and water dialyzed fraction, and analyzed spectrophotometrically at the wavelength of 460 nm. These two fractions were considered, respectively to be the brown pigments formed by lipid oxidation reactions for the formler and for the latter, to be the pigments developed by sugar-amino or Maillard reaction. The oxidation of lipid in anchovy meat during the storage was measured as the changes in Peroxide value and the color development of thiobarbituric acid reaction. It is summarized from the results that the rate of both reactions, lipid oxidation and browning, was affected by water activity levels. In regard to the changes in peroxide and TBA value during the storage, the propagation of lipid oxidation was obviously accelerated at lower humidities whereas the development of browning progressed at the higher. These two reactions occurring simultaneously and contrary in activity resulted in that the rate of deterioration occurring oxidatively or by browning, was the minimum at the water activity of 0.32-0.45 which were $7-9\%$ as moisture content and slightly higher value than that of monolayer (Aw=0.21, $5.11\%$ as moisture content). It is also noted that the lipid oxidative browning was presumed to dominate sugar-amino reactions so that the rate of browning of the meat was ultimately depended on the development of rancidity although sugar-amino reactions initiated earlier than the other at the first ten days of storage, particulary at higher humidity. At the lower humidity sugar-amino reactions were occurred gradually but lower levels in color development in contrast to the consistent increase in lipid oxidative browning.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.20 no.2
• /
• pp.139-147
• /
• 1991

The preservative effect of cellophane film packing on the quality of semi-salted and dried mackerel was studied. The product(P) of semi-salted and dried mackerel was prepared from raw mackerel by filleting, cleaning, soaking in 15%9v/w) salt solution for 30min, draining, packing with cellophane film (PT# 300, thickness:$20{\mu}{\textrm}{m}$) and drying for 4 hrs at $40^{\circ}C$ in hot air dryer. The product (C) was also prepared without cellophane film packing after draining. The product (C) and (P) were stored at $5.0{\pm}0.5^{\circ}C$. After processing and during storage, moisture content of product (P) was higher than that of product (C), but contents of VBN(volatile basic nitrogen), amino nitrogen and TMA of product (P) on dry basis were lower than those of product (C). Viable cell count, TBA value, peroxide value and decreasing rate of polyenoic acid of product (P) were also lower than those of product (C). In sensory evaluation, the shelf life of product (C) was about 9 days and that of product (P) was about 14 days. From the results of chemical and sensory evaluation, it was concluded that cellophane film packing was a good condition for preserving the quality of semi-salted and dried mackerel.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.2
• /
• pp.681-693
• /
• 2019

Multi-use ophthalmic solutions are used many times after opening; therefore, there is a high possibility of decreased quality during use. This study was conducted to determine the recommended use period of multi-use ophthalmic solutions based on evaluation of the stability by comparing stability evaluation regulations of the USA, EU and Korea We selected four types of multi-use ophthalmic solutions (Olopatadine (Olo), Fluorometholone (Flu), Dorzolamide (Dor), Timolol (Timol)) that are frequently marketed in Korea and evaluated their stability during storage according to the actual usage method after opening. The Olo had a decrease in assay and preservative content at 2 months after opening, while Flu showed a significant difference from day 28 after opening. For Dor, significant differences were observed from day 14 after opening in the assay and impurity test item and Timol showed a significant difference from day 28 after opening. Based on the results of the stability test Olo and Flu should only be used within 28 days of opening, while Dor and Timol should be used within 14 days of opening. Therefore, we suggest that regulations system related use periods of multi-use ophthalmic solutions designed as aseptic preparations should be improved based on the results of stability tests after opening.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.47 no.4
• /
• pp.281-287
• /
• 2021

In this study, we analyzed the cosmetic applicability of extract from snow tea, native to Lijiang, Yunnan-province, China. After confirming the species as N. grossedentata through DNA analysis of Lijiang snow tea, experiments were conducted using representative tea, green tea, and a representative control group for each efficacy analysis. Both teas were extracted using 70% (v/v) ethanol aqueous solution. The polyphenol content in the Lijiang snow tea extract (gallic acid equivalent, 23.9 ± 3.2 mg/mL) was higher than that in green tea extract (16.4 ± 2.3 mg/mL). In contrast, the antioxidant (Radical scavenging, IC₅₀ 104 ㎍/mL), tyrosinase enzyme inhibitory (whitening agent, IC₅₀ 40.7 ㎍/mL), and Escherichia coli growth inhibitory (preservative) activities (IC₅₀ 2.85 mg/mL) were analyzed based on the solid content in the extract, and it was confirmed that the activities of Lijiang snow tea extract were superior to those of green tea extract (radical scavenging, IC₅₀ 234 ㎍/mL. It also showed similar efficacy to previously used active substances such as antioxidants (vitamin C, IC₅₀ 108 ㎍/mL), whitening agents (vitamin C, IC₅₀ 80㎍/mL), and preservatives (methylparaben, IC₅₀ 4.35 mg/mL). However, green tea was found to be better in collagenase inhibition activity (anti-wrinkle). Through this study, the cosmetic application potential of Lijiang snow tea is high.

• Applied Chemistry for Engineering
• /
• v.33 no.4
• /
• pp.394-401
• /
• 2022

The synthesis of 1,2-alkylaminopropanediols (1,2-AAPs) was designed to improve the hydrophilicity of linear 1,2-alkanediols having 10, 12, 14, and 16 carbon atoms in the alkyl chain. 1,2-AAPs were synthesized by reacting 3-monochloro-1,2-propanediol (3-MCPD) with linear alkylamines having 10, 12, 14 or 16 carbon atoms in an ethanol solvent at 40℃ for 2 h. The yield and purity of four types of 1,2-AAPs synthesized were found to be in the range of 51-58% and 85-99%, respectively. The amine salts of four types of 1,2-AAPs were prepared from a purified paste or solid compound by adding an acidic solution (HCl) to pH 7, and then their solubilities and antibacterial effects were tested. 1,2-decylaminopropanediol, 1,2-dodecylaminopropanediol, and 1,2-tetradecylaminopropanediol were all dissolved in water at concentrations of 100%, 50%, and 0.1%, respectively, however 1,2-hexadecylaminopropanediol was not. The antibacterial effect was improved as the length of the alkyl chain increased. As a result of confirming the preservative effect of the lotion (cosmetic formulation) applied with 1,2-AAP for application, it showed very strong antibacterial activity at low concentrations ranging from 0.005% to 0.2%.

• Journal of Korean Ophthalmic Optics Society
• /
• v.8 no.2
• /
• pp.119-127
• /
• 2003

We measured the effect of wettability of six MPSs for RGP lens. The used MPSs(multipurpose solutions) were OPTI-SOAK(ALCON), SOLO care hard(CIBA Vision), Total care(ALLERGAN), Simplicity(BOSTON). Wetting and Soaking Sol.(Bausch & Lomb) and Aquas-multi(Saehan). These MPSs keeps hydrophilic property of lens surface and increase the effect of cleaning or increase the effect of preservative effect. To compare with the effect of wettability we followed the way of contact angle measurement which was general way to measure wettability and compared lens which was conducted by each MPS made by different companies. As a control, 0.9% NaCl solution and artificial tears were used. The degree of the effect of wettability was decided by contact angle. It is hydrophilic property nearby $0^{\circ}$ of contact angle and it is closed by hydrophobic property as it increases. To compare with the effect of wettability we followed the way of contact angle measurement which was general way to measure wettability and compared lens which was conducted by each MPS made by different companies. As a control, 0.9% NaCl solution and artificial tears were used. The degree of the effect of wettability was decided by contact angle. It is hydrophilic property nearby $0^{\circ}$ of contact angle and it is closed by hydrophobic property as it increases. The results showed that every lens was nearby hydrophilic property within $25^{\circ}{\sim}36^{\circ}$. Also, it was differed by various factors. The surface tension showed various differences between 19.8 and 31.3(mN/m). In the viscosity, MPSs represented the highest viscosity between $4^{\circ}C$ and $20^{\circ}C$. It was much higher than compared with the viscosity of soft lens MPS. This experiment could be used to grasping the interaction between solutions used to MPS and the natural endowments of lens and to considering the relations of different factors effecting the wettability.

• Horticultural Science & Technology
• /
• v.28 no.4
• /
• pp.609-617
• /
• 2010

The effect of vase water temperature and leaf number on water relations and senescence responses was determined in cut roses. Freshly harvested 'Red Sandra' roses were re-trimmed to 50 cm leaving two or four upper leaves and held in one of three solutions: ambient temperature distilled water ($23^{\circ}C$; AT-DW), low temperature distilled water ($7^{\circ}C$; LT-DW) and low temperature preservative solution (LT-PW). Flowers were kept in an environmental controlled room. Treatment effects evaluated were vase life, flower diameter, and changes in fresh weight and water uptake. Differences in water relations were determined by measuring $CO_2$ assimilation, stomatal conductance, and stem water flux rate (SFR). The water uptake rate was significantly increased in roses in LT-DW and decreased in those in LT-PW. While showing lower solution uptake rate during vase period, roses in LT-PW exhibited greatest fresh weight, longest positive water balance duration and largest flower diameter. Flowers with two leaves attached exhibited a higher fresh weight and improved water balance, thereby extending vase life. $CO_2$ assimilation rate and stomatal conductance were significantly decreased by placing flowers in LT-PW, yet increased by reducing leaf number to two leaves on the flower stems. Compared to the upper stem, the SFR of the basal stem of roses in AT-DW was lower, whereas SFR in basal stems of roses in LT-DW was much higher, suggesting that low-temperature water improved the hydraulic conductance in the stems. In contrast, roses in LT-PW had a stable SFR during the experimental period and displayed a similar pattern in SFR between upper and basal portions of the stems. Consequently, the vase life of cut roses in LT-PW and LT-DW was extended by more than eight and four days, respectively, compared to those in AT-DW.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.18 no.5
• /
• pp.401-408
• /
• 1985

In order to develop new types of product which can offer a sanitary and preservative duality, and convenience to consumers in marketing and cooking particularly in urban area, two processing methods of ready-to-cook food materials with dark fleshed fishes like sardine and mackerel were investigated. A method applied, in this work, is processing of ready-to-cook sardine meat "surimi" in which sardine meat is treated with alkaline solution to stabilize myofibrillar proteins, washed thoroughly with water to remove soluble components, and added with a proper amount of polyphosphate and sorbitol to enforce the functional property of meat such as water holding capasity, elasticity, and gel strength. The textural properties of fish meat paste made from the "surimi" meat were greatly dependent upon the stability of myofibrillar proteins and the elimination of water soluble components. The salt soluble proteins of sardine meat were so unstable in post-mortem stage that the gel forming ability was lost within 3 days at $5^{\circ}C$ storage and 2 to 3 weeks even at $-20^{\circ}C$ although the freshness was well kept for a week at $5^{\circ}C$ and several months of storage at $-20^{\circ}C$. A proper way of treatment to keep the proteins stable was that fish meat must be washed with $0.4\%$ sodium bicarbonate solution followed by 3 to 4 times washing with water. This resulted in removal of $80\%$ water soluble proteins and 50 to $60\%$ lipids. The addition of polyphosphate and sorbitol affected the stability of proteins during the storage of "surimi" meat. When phosphate and sorbitol were added in the ratio of $0.3\%:\;0.3\%,\;0.6\%:\;3\%,\;0.6\%:\;6\%,\;0:\,0.3\%\;and\;0.3\%:\;0$, the gel forming ability terminated in 35 days, 21 days, 14 days, 14 days, and 14 days of storage at $-30^{\circ}C$, respectively, while that of the control was 7 days. And it was also noteworthy that at least 8.0 mg/g of salt soluble protein nitrogen content was required for gel formation.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.19 no.1
• /
• pp.52-59
• /
• 1986

As one of trials to process instant sardine foods which can be preserved at room temperature, three kinds of products were prepared as seasoned-dried product (control, C), liquid smoked seasoned-dried product(S) and antioxidant treated seasoned-dried product(E), and their processing conditions and quality stability during storage were examined. Raw sardines were dressed, steamed and then filleted. The sardine fillets were seasoned with the mixed seasoning solution containing $28.0\%$ of sorbitol, $14.0%$ of sugar, $5.6\%$ of table salt, $1.8\%$ of monosodium glutamate, $0.6\%$ of garlic powder and $50.0\%$ of water at $5^{\circ}C$ for 15 hours, and dipped for 45 seconds in $10\%$ Smoke-EZ solution. After liquid smoking, the seasoned and liquid smoked sardine fillets were dried at $45^{\circ}C$ for 4 hours, vacuum packed in laminated plastic film bag(polyester/casted polypropylene= $12{\mu}m/70{\mu}m,\;15{\times}16cm$), and finally pasteurized in water at $95^{\circ}C$ for 30 minutes. The results obtained from chemical and microbial experiments during storage are as follows : the moisture contents, water activity and pH of the products showed little change, and VBN of them slightly increased during storage. The TBA value and POV of the products (E, S) were lower than those of control product(C) considerably. In color values, L value (linghtness) decreased while a and b value (red and yellow) revealed a tendency to increase during storage. The fatty acid composition of the products were similar to those of raw sardine, the predominant fatty acids were 16:0, 20:5, 18:1 and 22:6. The products (E, S) have a good preservative effect on highly unsturated fatty acids during storage. Viable cell counts of those products were negative and histamine contents were less than 2.0 mg/100 g. Among the texture profiles, hardness, elasticity and cohesiveness of the products slightly decreased during storage. Judging from the sensory evaluations, liquid smoked seasoned-dried product(S) was the most desirable, and the products could be preserved in good condition for 40 days at $25{\pm}3^{\circ}C$.