The purpose of this study is to clarify the regional differences in biotin contents in foods between Japan, America, Canada, German, and Denmark by comparing the published data. There was a positive correlation in meat group and egg group between Japan and Western countries. But, in vegetable group a positive correlation was not observed. The possible reason might be that biotin biosynthesis in vegetables is different between Japan and Western countries due to differences of cultivation conditions. Then, to study the effect of cultivation conditions on biotin biosynthesis in plants, pea sprouts were hydroponically cultivated under 5 conditions (Control (C) : 22℃, 10-h light/14-h dark, Negative control (NC) : 22℃, 10-h light/14-h dark, addition of acidomycin, Short-time lighting (SL) : 22℃, 5-h light/19-h dark, No lighting (NL) : 22℃, 24-h dark, Low temperature (LT) : 4℃, 10-h light / 22℃, 14-h dark). Biotin contents in NL and LT were remarkably lower than those in C (p < 0.05). Moreover, biotin contents in SL also decreased to approximately 75 % of those in C, although statistical significance was not observed. These results strongly suggest that cultivation conditions of plants affect biotin biosynthesis, leading to the differences of biotin contents in vegetables among the regions for planting.
