Vitamin contents (mg/100g dry weight)

Organic soil culture

Hydroponic culture

Natural sun light

Artificial sun light

1% collagen water solution

Liquid fertilizer

Total ascorbic acid

367.5

262.5

450.0

434.0

α-tocopherols

12.8

27.5

20.2

12.1

γ-tocopherols

3.4

5.0

4.6

3.0