• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.37 no.1
• /
• pp.1-21
• /
• 2011

This review describes several kinds of emulsification methods for nanoemulsions and the application of nanoemulsions. Nanoemulsion droplet sizes fall typically in the range of 20 ~200 nm and show narrow size distributions. Although most of the publications on either oil-in-water (O/W) or water-in-oil (W/O) nanoemulsions have reported their formation by dispersion or high-energy emulsification methods, an increased interest is observed in the study of nano-emulsion formation by condensation or low-energy emulsification methods based on the phase transitions that take place during the emulsification process. Phase behaviour studies have shown that the size of the droplets is governed by the surfactant phase structure (bicontinuous microemulsion or lamellar) at the inversion point induced by either temperature or composition. Studies on nanoemulsion formation by the phase inversion temperature (PIT) method have shown a relation between minimum droplet size and complete solubilization of the oil in a microemulsion bicontinuous phase independently of whether the initial phase equilibrium is single or multiphase. Due to their small droplet size nanoemulsions possess stability against sedimentation or creaming with Ostwald ripening forming the main mechanism of nanoemulsion breakdown. An application of nanoemulsions is the preparation of nanoparticles using a polymerizable monomer as the disperse phase where nanoemulsion droplets act as nanoreactors, cosmetics and controlled drug delivery. In this review, we mainly focus on the cosmetics.

• Journal of the Korean Applied Science and Technology
• /
• v.31 no.4
• /
• pp.642-652
• /
• 2014

The synthesis of octenyl succinyl ${\beta}$-gucan (OSA-${\beta}$-glucan) was carried out and its interfacial properties at the oil-water interface and in emulsion systems were investigated. An aqueous ethanol system as a reaction media was used to facilitate the synthesis process; 10% (w/w) ethanol found to be the best as it showed a maximum degree of substitution (DS: 0.0132). FT-IR showed a characteristic absorption spectrum at $1736cm^{-1}$, indicating the esterification of octenyl succinyl groups to ${\beta}$-glucan backbone. As for interfacial tension measurements, it was decreased with increasing concentration of OSA-${\beta}$-glucan in the aqueous phase and when NaCl was added to aqueous OSA-${\beta}$-glucan solution in the range of 0.01 M to 0.1 M and also when pH was raised (pH 3 ~ pH 9). In systems of emulsion stabilized with OSA-${\beta}$-glucan, fat globule size found to decrease with increasing concentration of OSA-${\beta}$-glucan, showing a critical value of about $0.32{\mu}m$ at 0.5 wt%. When the OSA-${\beta}$-glucan emulsions were stored, it was found that fat globule size was increased with storage time and particularly pronounced increase was observed in emulsion with 1% OSA-${\beta}$-glucan, possibly due to depletion flocculation. Results of creaming stability evaluated by light scattering technique showed that it was more stable in emulsions containing smaller fat globule size. Surface load of OSA-${\beta}$-glucan in emulsions increased with increasing concentration of OSA-${\beta}$-glucan, suggesting a multilayer adsorption.

• Korean Journal of Food Science and Technology
• /
• v.47 no.2
• /
• pp.217-223
• /
• 2015

We investigated the emulsifying properties of barley octenyl succinic anhydride (OSA)-${\beta}$-glucan, such as changes in the fat globule size and zeta-potential as influenced by pH or the addition of NaCl. Additional experiments to fabricate a suitable co-surfactant system were also performed. We found that the fat globule size in OSA-${\beta}$-glucan emulsions increased upon lowering the pH (i.e., under acidic conditions) or increasing the NaCl concentration. These results were confirmed through microscopic observation. Co-surfactant hydrophilic Tween 20 was found to be suitable for the OSA-${\beta}$-glucan emulsion, which facilitated the formation of smaller fat globules and enhanced the creaming stability when it was added in >0.2 wt% concentration. From the results of the surface load of OSA-${\beta}$-glucan in emulsions, Tween 20 addition enhanced the stability probably by the co-adsorption of the two surfactants at the droplet surface.

• Journal of the Korean Applied Science and Technology
• /
• v.29 no.2
• /
• pp.205-213
• /
• 2012

In this study, the stability of cream containing the ethyl acetate fraction of C. obtusa leaf extract was evaluated. The pH, viscosity, and absorbance were measured under the 4 different temperatures (4, 25, 37 and $45^{\circ}C$) and under the sun light during the 12 weeks. The control cream without containing the extract did not show pH change under the different temperatures mentioned above. However, the pH of the cream with the extract was decreased 0.11 at $4^{\circ}C$ and $25^{\circ}C$. Under the $37^{\circ}C$, $45^{\circ}C$ and sun light condition, the pH was decreased 0.55, 0.84 and 0.59, respectively. After treating the cream for 12 weeks under the different temperatures, the viscosity was measured for the cream containing the extract and control cream. The values were decreased by 2,404 cPs in average compared to the initial value for the former and control cream were decreased by 1,296 cPs in average for the latter. On the other hand, the viscosity of control cream treated under the $45^{\circ}C$ for 12 weeks was decreased (1,915 cPs) relative to the cream containing the extract, which showed 3,810 cPs decrease in viscosity. The cream containing the extract did not show absorbance change at $4^{\circ}C{\sim}37^{\circ}C$ for 12 weeks. Instead, the absorbance of the cream treated under $45^{\circ}C$ and sun light condition was decreased 32.5 % and 35.2 %, respectively. This decrease in absorbance is relatively small compared to the 54.8 % decrease of the extract sampled from the cream using ethanol solution. This indicates that the extract is stabilized in the cream. In addition, any change in color or smell was not observed through 12 weeks of the experimental time period. Also physical changes as creaming and cohesion were not shown. The results show that the cream containing C. obtusa leaf extract was relatively stable. However, it is concluded that it is still not clear in the stability of the cream containing the extract when it is stored for a long time. Accordingly, it is suggested that further study is needed for the application of the extract to cosmetics.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.35 no.4
• /
• pp.301-307
• /
• 2009

In the previous study, we evaluated and reported about the anti-oxidative activities of extract/fraction of Castanea crenata leaf. Extract/fraction of Castanea crenata leaf showed excellent free radical scavenging activity, cell protective activity and inhibitory activity on tyrosinase and elastase. In this study, in order to investigate the stability of cream containing 0.2 % Castanea crenata ethyl acetate fraction. pH, viscosity, and absorbance were measured under 4 different temperature ($4^{\circ}C$, $20^{\circ}C$, $37^{\circ}C$, $45^{\circ}C)$ and under the sun light at 2 weeks intervals for the 8 weeks. The variations on pH and viscosity of all experimental creams were similar to control cream. The absorbance variation of extract from experimental cream at 353 nm was in the order: under the sun > $45^{\circ}C$ > $37^{\circ}C$ > $20^{\circ}C$ > $4^{\circ}C$. It shows that ethyl acetate fraction in the cream can be oxidized under the sun. The bad smell and discoloration were not shown. Also, physical changes as creaming and cohesion were not shown. Also, transepidermal water loss (TEWL) and water contents in skin were measured. The cream containing Castanea cranata leaf extract was applied to the right lower arm. After 120 min, TEWL of parts was decreased as 29.7 % (experimental cream) and 5.4 % (control cream) respectively. And the water contents in skin were increased 22.6 % (experimental cream) and 24.7 % (control cream) respectively. It was confirmed that a cream containing ethyl acetate fraction of Castanea crenata leaf shows the superior moisturizing effect. The results showed that Castanea crenata leaf extract could be used as a new active ingredient for anti-aging cosmeceuticals.

• Korean Journal of Food Science and Technology
• /
• v.4 no.3
• /
• pp.187-193
• /
• 1972

In this study, the physical and chemical properties of 7 kinds of Korean domestic margarines and 4 kinds of bakery margarines were analyzed and compared with each other samples. The results are summarized as follows: 1) The average moisture content of domestic margarines was 16.15% and that of bakery margarines was 16.89%. The average oil content of domestic margarines was 80.92% and bakery margarines had average 79.73% of oil content. 2) The acid value of fat and oils seperated from samples were below 1.0. The average melting point of domestic and bakery margarines were $34.9^{\circ}C$ and $36.4^{\circ}C$, respectively. The average saponification value of the domestic margarines was 160.8 and that of bakery was 177.3. The average iodine value were 76.4 and 67.5 each of the domestic and bakery margarines. 3) All the samples contained greater percentage of oleic and palmitic acid than the other fatty acids. Contents of the fatty acids below $C_{12}$ and the unsaturated fatty acids were significantly found in domestic margarines whereas those of more than $C_{20}$ were evident in bakery margarines. 4) At $20^{\circ}C$, domestic margarines showed 150-300 hardness index, while bakery margarines showed less than 200. 5) At $10^{\circ}C$, majority of the domestic margarines showed about $32{\sim}40$ of solid fat index and generally, bakery margarines had higher solid fat index than domestic margarines. 6) At $20^{\circ}C$, $3{\sim}4% of oil-off value was most commonly found (43% of all samples). 7) Creaming value of all the samples showed rapid increase in 10 minutes. After 20 minutes, it showed steady increase in both of the domestic and bakery margarines. After 40 minutes, the steady decrease continued in the case of bakery margarines while this was not evident in the case of domestic margarines.

• Microbiology and Biotechnology Letters
• /
• v.40 no.3
• /
• pp.237-242
• /
• 2012

In this study, the skin moisturing effect and stability of cream containing L. cuneata G. Don extract (ethyl acetate fraction) were evaluated. The skin hydrating effect of the cream containing extract was 1020% higher than the placebo cream, and the TWEL of the cream containing extracts was decreased to $7.7g/m^2h$ compared to the control ($10.2g/m^2$) and placebo cream ($8.9g/m^2$). The pH, viscosity, and absorbance were measured under the 4, 25, 37, $45^{\circ}C$ and the sun light during the 12 weeks. The pH change between cream containing extract and placebo cream did not show the significant difference under the 4, 25, 37, $45^{\circ}C$ except for the sun light. Both creams showed high decrease (about 59%) of viscosity at $45^{\circ}C$. However, there was no significant change under other conditions. The absorbance of the cream containing the extract and the placebo cream was decreased similarly at all conditions. This decrease in absorbance was relatively small compared to the decrease of absorbance of the extract in ethanol solution under the sun light (Fig. 7). In addition, any change in color or smell of the cream was not observed during the 12 weeks. Also physical changes as creaming and cohesion were not shown. These results indicate that the cream containing L. cuneata extract has the skin moisturizing effect and is relatively stable. Therefore, it is suggested that the ethyl acetate fraction of L. cuneata extract could be applicable to cosmetics as a new cosmetic material with its antioxidative and antibacterial activities reported previously.