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Clinical Applications of Epidermal Stem Cells

Epidermal stem cells (EpiSCs) are mainly located at the basal layer of the epidermis. These cells repair minor injuries of the skin and replace dead skin cells. However, EpiSCs’ cannot heal severe wounds such as major burns or those from diabetes or hereditary disorders. In such cases, culturing the epidermal stem cells from the patient is possible and has yielded successful treatment options, such as laboratory-grown skin grafts. These grafts are synthesized using a patient’s own EpiSCs...
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Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
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Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of peroxy acids to...
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Structure and Nomenclature of Epoxides

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Two new epoxysteroids from Helianthus tuberosus.

Xiao-Dong Li1, Feng-Ping Miao, Nai-Yun Ji

  • 1Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China.

Molecules (Basel, Switzerland)
|October 15, 2011
PubMed
Summary

Two novel epoxy steroids were identified in Helianthus tuberosus from China

Area of Science:

  • Natural Product Chemistry
  • Phytochemistry
  • Marine Biotechnology

Background:

  • Helianthus tuberosus (sunflower) is a plant source for bioactive compounds.
  • Salinized coastal environments can influence plant secondary metabolite production.
  • Steroids are a class of organic compounds with diverse biological activities.

Purpose of the Study:

  • To isolate and characterize steroid compounds from Helianthus tuberosus.
  • To investigate the chemical diversity of steroids in plants grown in salinized land.
  • To evaluate the bioactivity of isolated new compounds.

Main Methods:

  • Extraction and isolation of compounds using chromatographic techniques.
  • Structure elucidation using Nuclear Magnetic Resonance (NMR) spectroscopy (1D and 2D) and Mass Spectrometry (MS).

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  • Bioactivity screening for antibacterial and antifungal properties.

    • Main Results:

    • Isolation of two new epoxy steroids (1 and 2) and ten known steroids.
    • Unambiguous structural determination of all isolated compounds.
    • Compounds 1 and 2 demonstrated weak antibacterial activity but no antifungal activity.

    Conclusions:

    • Helianthus tuberosus from salinized land is a source of diverse epoxy steroids.
    • The identified steroids represent novel chemical entities with potential biological applications.
    • Further research is warranted to explore the pharmacological potential of these compounds.