Nagao M, Takahashi Y, Yamanaka H, Sugimura T
Mutat Res. 1979 Oct;68(2):101-6. doi: 10.1016/0165-1218(79)90137-x.
Coffee prepared in the usual way for drinking contains a substance(s) that is mutagenic to Salmonella typhimurium TA100 without mammalian microsomal enzymes. One cup of coffee (200 ml) contains mutagen(s) inducing 1.4-4.6 X 10(5) revertants under standard conditions. Instant coffee too is mutagenic to TA100 and one cup of instant coffee prepared from 1 g of coffee powder and 200 ml of water induced 5.6-5.8 X 10(4) revertants of TA100. Caffeine-free instant coffee also has similar mutagenicity. Addition of microsomal enzymes abolished the mutagenicity. Black tea, green tea and Japanese roasted tea were also mutagenic to TA100 without S9 mix and one cup of these teas prepared in the ordinary way produced 1.7-3.8 X 10(4) revertants of TA100. Black tea and green tea were also mutagenic to TA98 in the presence of S9 mix after treatment with a glycosidase from Aspergillus niger, hesperidinase. This type of mutagen in one cup of black tea induced 2.4 X 10(5) revertants of TA98.
以通常饮用方式制备的咖啡含有一种物质，该物质在无哺乳动物微粒体酶的情况下对鼠伤寒沙门氏菌TA100具有致突变性。一杯咖啡（200毫升）中的诱变剂在标准条件下可诱导1.4 - 4.6×10⁵回复突变体。速溶咖啡对TA100也有致突变性，由1克咖啡粉和200毫升水制备的一杯速溶咖啡可诱导TA100产生5.6 - 5.8×10⁴回复突变体。无咖啡因速溶咖啡也具有类似的致突变性。添加微粒体酶可消除致突变性。红茶、绿茶和日本焙茶在无S9混合物时对TA100也有致突变性，以普通方式制备的一杯这些茶可产生TA100的1.7 - 3.8×10⁴回复突变体。红茶和绿茶在用黑曲霉糖苷酶、橙皮苷酶处理后，在有S9混合物存在的情况下对TA98也有致突变性。一杯红茶中的这种诱变剂可诱导TA98产生2.4×10⁵回复突变体。
