• Title/Summary/Keyword: photodamage

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Diurnal and Seasonal Variation of Chlorophyll Fluorescence from Korean Fir Plants on Mt. Halla (한라산 구상나무 잎의 엽록소형광의 일변화와 계절적 변화)

  • 오순자;고정군;김응식;오문유;고석찬
    • Korean Journal of Environmental Biology
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    • v.19 no.1
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    • pp.43-48
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    • 2001
  • Chlorophyll fluorescence of needles of Korean fir (Abies koreana) plants and environmental factors of their natural habitat were investigated in order to obtain the information for environmental adaptation and conservation of Korean fir plants. The photochemical efficiency of photosystem II, Fv/Fm, of Korean fir needles was significantly low (0.19-0.36) in the winter, whereas it was high (0.8-0.86) in the summer. The Fv/Fm value of the winter was slightly higher at mid-day than at dawn, suggesting that mid-day environmental conditions of the winter were favorable on needles of Korean fir plants. In contrast, the mid-day Fv/Fm value of the summer maintained high (around 0.8). It indicates that mid-day environmental conditions of the summer did not induce photodamage, although it caused a slight decrease in the Fv/Fm values. The non-photochemical fluorescence quenching (NPQ) of Korean fir needles was very low (0-0.01) all through the day in the winter. However, it was high (0.76) at mid-day in the summer. These results suggest that Korean fir plants have a system for the protection of PS II from mid-day environmental stresses of the summer. In the winter, the Fv/Fm values were positively correlated with temperature, light intensity and relative humidity, although NPQ values showed no correlation with any of them. In the summer, the Fv/Fm values were positively correlated with relative humidity but negatively correlated with temperature and light intensity. These results indicate that increase of tempera-ture, light intensity and relative humidity lead to promotion of the photochemical efficiency in the winter and high temperature and light intensity may cause photoinhibition in the summer.

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Beneficial Effect of Collagen Peptide Supplement on Anti-aging Against Photodamage (콜라겐 펩타이드의 피부 광노화 예방 효과)

  • Kim, Jeong-Kee;Lee, Ji-Hae;Yang, Mi-Sook;Seo, Dae-Bang;Lee, Sang-Jun
    • Korean Journal of Food Science and Technology
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    • v.41 no.4
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    • pp.441-445
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    • 2009
  • Recent research has revealed that hydrolyzed collagen peptides have beneficial effects in various diseases such as osteoarthritis and human rheumatoid arthritis and also play a protective role in skin by improving the activity of antioxidants. In this study, we investigated the effects of a novel mixture (AP-CPM01) containing collagen peptides and elastin peptides on photoaged hairless mice skin both in vivo and in vitro. To evaluate the effects of AP-CPM01 on UVBinduced skin wrinkle formation in vivo, the hairless mice were exposed to UVB irradiation and orally administered the AP-CPM01 at 333 mg/kg per day for 10 weeks. The effects on skin appearance and epidermal thickness were measured using bioengineering and histochemical methods. In addition, the influence of AP-CPM01 on collagen metabolism in human skin fibroblasts was also investigated. The skin of mice in the AP-CPM01 treated group had better appearance and less wrinkling than that of mice in the control group. In the human fibroblast cells, the amount of de novo procollagen synthesis was increased after AP-CPM01 treatment, reflecting that AP-CPM01 can induce de novo procollagen synthesis and reduce UVB-induced skin wrinkle formation. These results suggest that AP-CPM01 is a potent candidate for antiphotoaging functions.

The Photoprotective Effects of Gynura Procumbens Against Photoaging: A Comparative Study Based on Extraction Methods (추출방법에 따른 명월초(Gynura Procumbens)의 광노화 완화 효과)

  • So Yeon Han;Da Yoon Lee;Ji Sun Moon;Hye Won Lee;Jae Hun Kim;Jae Ho Park
    • Korean Journal of Plant Resources
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    • v.37 no.2
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    • pp.101-109
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    • 2024
  • In this study, we investigated the antioxidant effects and active ingredients of Gynura Procumbens extracts obtained through various extraction methods for the development of natural-based cosmetics and pharmaceutical materials. The contents of compounds, total flavonoids, chlorogenic acid, and caffeic acid were compared at different concentrations, revealing the highest content of active ingredients in the 100% ethanol extract. Antioxidant activity assessed by DPPH and ABTS radical scavenging assays showed a concentration-dependent increase in antioxidant activity with the ethanol concentration. Additionally, we validated the DNA damage inhibition and anti-inflammatory effects of Gynura Procumbens extracts through UVB irradiation on Hs68 cell models. The 100% ethanol extract demonstrated significant inhibition of the expression of p-p53, γ-H2AX, iNOS, and COX-2 induced by UVB, indicating its potential in alleviating photodamage effects. Consequently, the efficient extraction of Gynura Procumbens for skin functional material development was confirmed, suggesting the suitability of ethanol or alcohol-based solvents.