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- Jo, Ji Song, et al.
(författare)
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Anti-wrinkle activity of beta-carotene extracted & purified from recombinant Escherichia coli
- 2008
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Ingår i: KSBB Journal. - 1225-7117 .- 2288-8268. ; 23:6, s. 513-518
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Tidskriftsartikel (refereegranskat)abstract
- This paper described the extraction/purification of β-carotene from recombinant E.coli and evaluation of anti-wrinkle activity of purified β-carotene. No significant differences in extraction yields were observed when hexane or isobutyl acetate was used. However, extraction from wet-cell cake resulted in 2-fold higher amount of β-carotene than that from dry cells. Disruption of 5 g-wet cells by ultrasonic homogenizer, acetone dehydration, extraction with isobutyl acetate resulted in 36 mg of β-carotene corresponding to 61.2% of recovery. The formation and separation of ββ-carotene crystal improved the purity. 633 mg of β-carotene crystal with 93% purity was obtained from 223 g/L of wet-cell cake harvested from 2.5-L fed-batch culture broth. The cultures of normal human primary fibroblast were performed to investigate the effect of β-carotene on cytotoxicity as MTT assay and anti-wrinkle activity as collagen synthesis assays. 1.7μM of β-carotene was found to be optimal concentration at which 1.4-fold higher amount of collagen was synthesized than that in absence of β-carotene. This indicates that highly purified β-carotene can be obtained from recombinant E.coli by applying simple method with less toxic solvent and can be used in functional cosmetics as anti-wrinkle agent.
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| 2. |
- Kim, Woo Sik, et al.
(författare)
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Film Structure-Induced Resonant Oscillation Changes in a Poly Acrylic Acid Modified Quartz Crystal Sensor
- 2008
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Ingår i: Molecular Crystals and Liquid Crystals. - : Informa UK Limited. - 1542-1406 .- 1563-5287. ; 492, s. 221-228
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Tidskriftsartikel (refereegranskat)abstract
- A poly acrylic acid (PAA) film has been fabricated on a quartz crystal microbalance to study the dynamic property changes induced by different pH values. The experiment has been performed by a two-step. First, using the self-assembly procedure, the gold surface of quartz crystal was chemically modified to allow the graft copolymerization with PAA. Secondly, the resonant frequency response of the PAA-modified QCM was investigated by varying the pH values. The result shows an interesting oscillation property change nearby pH 5.5, and a possible mechanism for the change is proposed considering the oscillation properties of quartz crystal and the physical properties of PAA. Finally, a polymer film complex of PAA/collagen was also used to confirm the proposed mechanism.
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