"The minimum amount of vernonioside A1 for a bitter taste was determined as 7 μg in a tentative sensory test with a paper disc (1 cm2, 0.2 mm thickness), and the activity was almost equal to that of quinine sulfate. Vernonioside B1, on the other hand, did not show any bitter taste even at 200 μg."
"The minimum amount of vernonioside A1 for a bitter taste was determined as 7 microg in a tentative sensory test with a paper disc (1 cm2, 0.2 mm thickness), and the activity was almost equal to that of quinine sulfate. Vernonioside B1, on the other hand, did not show any bitter taste even at 200 microg." "The structures of 1 and 2 are quite new... Thus, the structure of vernonioside A1 was determined to be 1... Hence, hydroxylation at C(16) may be significant for the bitter taste."
限界: 「may be significant」という著者自身の推測的表現であり、C(16)水酸化とB系全体(B1-B3)の非苦味を直接検証した実験ではない。パネル人数・判定基準の記載なし。