Mukherjee P, Sarkar D, Sharma A
Department of Botany, University of Calcutta, India.
Food Chem Toxicol. 1997 Jul;35(7):657-61. doi: 10.1016/s0278-6915(97)00044-6.
Black tea infusion in water, in concentrations simulating human consumption, was administered by gavage daily to male Swiss mice for 7 days. One set was given tea once daily and the other twice daily. The mice were then exposed to two known clastogens: chromium (VI) as potassium dichromate and mitomycin C on day 7, and killed after 24 hr. Chromosome damage was studied in preparations made from bone marrow following colchine injection of all mice, and examination of the cells after pretreatment in hypotonic solution, fixation, air drying one and staining with Giemsa solution. No effect was observed in mice given tea once daily. In mice administered tea twice daily, the frequencies of chromosomal aberrations and damaged cells were increased as compared with those of the control in distilled water. Administration of tea twice daily for 7 days could not reduce the clastogenic effects of mitomycin C significantly. The damage due to potassium dichromate was reduced significantly, almost to the level of distilled water. Dietary administration of black tea infusion could therefore significantly protect against clastogenic activity of chromium compounds though it was itself mildly clastogenic.
将模拟人类饮用浓度的红茶水溶液，每天经口灌胃给予雄性瑞士小鼠，持续7天。一组小鼠每天给予一次茶，另一组每天给予两次茶。然后在第7天，让小鼠接触两种已知的致染色体断裂剂：重铬酸钾形式的铬（VI）和丝裂霉素C，24小时后处死小鼠。对所有小鼠注射秋水仙碱后，取骨髓制成涂片，经低渗溶液预处理、固定、空气干燥、吉姆萨溶液染色后，研究染色体损伤情况。每天给予一次茶的小鼠未观察到影响。与饮用蒸馏水的对照组相比，每天给予两次茶的小鼠，染色体畸变和受损细胞的频率增加。连续7天每天给予两次茶，不能显著降低丝裂霉素C的致染色体断裂作用。重铬酸钾造成的损伤显著降低，几乎降至蒸馏水对照组的水平。因此，通过饮食给予红茶水溶液虽然其本身有轻度致染色体断裂作用，但能显著保护机体免受铬化合物的致染色体断裂活性影响。
