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Microemulsion Development for Enhancing the Stability of Green Tea (Camellia sinesis) Extract |
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| รหัสดีโอไอ | |
| Creator | Aujsharaporn Singhan, Ratana Indranupakorn |
| Title | Microemulsion Development for Enhancing the Stability of Green Tea (Camellia sinesis) Extract |
| Publisher | Faculty of Pharmaceutical Sciences KKU, MSU, UBU |
| Publication Year | 2558 |
| Journal Title | Isan Journal ofPharmaceutical Sciences |
| Journal Vol. | 11 |
| Journal No. | 4 |
| Page no. | 40-56 |
| Keyword | Green tea, Microemulsion, Pseudoternary phase diagram, Stability test |
| ISSN | 19050852 |
| Abstract | The aim of the research study was to develop the microemulsion formulation for enhancing the stability of catechins, the main constituent in green tea extract. Based on the single isotropic region produced in the pseudoternary phase diagram, the effects of the surfactant mixtures (Span80: Cremophor RH40; Span80: Kolliphor EL and Span80: Kolliphor HS15 [1:1]) on the phase behavior and the concentrations of cosurfactant (isopropanol, IPA), oil phase (jojoba oil) and water in the systems were evaluated. The selected microemulsion systems were investigated in terms of characteristics, such as clarity, droplet size, polydispersity index (PI), conductivity, pH and viscosity. The stability tests of microemulsion were also performed for the further optimization of the system. The results indicated that the clear w/o microemulsion containing the mass of 0.5% green tea extract, 49.90% surfactant mixtures consisting of Span80 and Cremophor RH40 at the ratio of 1:1, 24.31% jojoba oil, 25.29% water to IPA ratio 1:1 remained stable during storage and exhibited the droplet size in microemulsion range, low viscosity, acceptable pH and conductivity. Transmission electron microscope (TEM) was used to image the microemulsion droplets and revealed the spherical feature of the particles. Furthermore, the percentages of the remaining active constituents, caffeine, epicatechin and epigallocatechin gallate, in the optimized microemulsions after stability test were analysed by the developed HPLC method in comparison with the prepared green tea extract gel. It was found that the optimized microemulsions contained the contents of these three active compounds significantly higher than the prepared green tea extract gel after storage at room temperature up to 3 months and 6 heating/cooling cycles. It could be concluded that the developed microemulsion system significantly enhances the stability of green tea extract. |
