X-ray-mediated vitamin D synthesis.

Area of Science:

• Biochemistry
• Radiation Chemistry
• Nutritional Science

Background:

• Vitamin D synthesis is primarily associated with ultraviolet B (UVB) light exposure.
• Precursors like 7-dehydrocholesterol and ergosterol are converted to vitamins D2 and D3 via UVB radiation.

Purpose of the Study:

• To investigate the potential of ionizing X-ray irradiation to induce vitamin D formation from its precursors.
• To compare the efficacy of X-ray irradiation with traditional UVB irradiation for vitamin D synthesis.

Main Methods:

• Crystalline and oil-dissolved 7-dehydrocholesterol and ergosterol were subjected to X-ray irradiation at a dose of 25 kGy.
• Vitamin D yields were quantified and compared to those obtained from UVB irradiation at varying doses (20 and 200 mJ/cm²).
• The effect of X-ray irradiation was also assessed in complex matrices like mushrooms, yeast, and rodent feed.

Main Results:

• X-ray irradiation at 25 kGy produced significant amounts of vitamin D3 (94 μg/g) and D2 (74 μg/g) from crystalline precursors.
• When precursors were dissolved in oil, X-ray exposure yielded 70 ng/g vitamin D3 and 45 ng/g vitamin D2.
• Vitamin D yields from X-ray irradiation were comparable to those achieved with 20 mJ/cm² UVB, though high-dose UVB produced substantially more.

Conclusions:

• Ionizing X-ray irradiation represents a novel and unrecognized pathway for generating vitamin D.
• This finding opens new avenues for vitamin D production and fortification, particularly in food and feed applications.