Definition of dehydrocholesterol in English:
dehydrocholesterol
noundiːˌhʌɪdrə(ʊ)kəˈlɛstərɒldēˌhīdrōkəˈləstərôl
mass nounBiochemistry A derivative of cholesterol present in the skin. It can be converted to cholecalciferol (vitamin D₃) by the action of ultraviolet radiation.
Chemical formula: C₂₇H₄₄O
Example sentencesExamples
- The most important source of vitamin D for all individuals is the sunlight-driven conversion in skin of 7 - dehydrocholesterol to cholecalciferol.
- Since 7 - dehydrocholesterol is present in the skin in large quantities and only needs sunlight to be activated, vitamin D is often called the ‘sunshine vitamin.’
- High energy ultraviolet light enters the skin and causes the photochemical conversion of 7 - dehydrocholesterol to previtamin D 3, which at body temperature undergoes isomerization to vitamin D 3.
- In the skin 7 - dehydrocholesterol is converted to cholecalciferol following UV irradiation.
- Other types of UV dosimeters are based on the photodamage of DNA in spores, bacteria or bacteriophages or the conversion of 7 - dehydrocholesterol to previtamin D.
Origin
1930s: from dehydro- 'that has lost hydrogen' + cholesterol.