THE BLOCKING EFFECTS OF CHINESE ACTINIDIA SINENSIS PLANCH JUICE ON THE FORMATION OF N-NITROSAMINE
- VernacularTitle:中华猕猴桃汁的防癌作用——(二)在体外模拟胃液中对亚硝胺合成的阻断作用—Ames试验方法检测
- Author:
Puju SONG
;
Lin ZHANG
;
Lan DING
- Publication Type:Journal Article
- From:
Acta Nutrimenta Sinica
1956;0(03):-
- CountryChina
- Language:Chinese
-
Abstract:
The present investigation was undertaken to evaluate the role of the Chinese fruit juice in blocking nitrosamine formation in vitro.A model system simulated the conditions (pH 3.3, 37℃) known, to exist in the stomach, was used in the experiments. Different amount of nitrite and aminopyrine was incubated with Chinese fruit juice or vitamin C solution or buffer solution for 1 hr. 0.1 ml samples were taken and then subjected to the Ames mutagenicity test. The tester strain TA100 of Salmonella typhi-murium was employed for the detection of mutagenicity due to the N-nitro-samine formed from sodium nitrite and aminopyrine. Test samples and bacteria with or without S-9 mixed with molten top agar and poured onto the minimal agar plates. After incubation, the sample, that gave at least a 2-fold increase in induced revertants, compared to spontaneous revertants, was considered to have mutagenic activity.It showed that the concentration of the precursors was at or above 5 mg/ ml with S-9 and without juice. the samples exhibited mutagenic activity. It suggested that the nitrosamine was formed in this system. While the incorporation of Chinese fruit juice was found to inhibit the formation of nitrosamine at 5mg/ml and 8mg/ml. The cultures did not show mutagenic activity. The induced revertant colonies per plate was 252 ? 4.2. The Chin esefruit juice is more effective than that of vitamin C, the induced revertant colonies per plate was 445 ? 81.2, which shows mutagenic. The difference between the cultures of Chinese fruit juice and vitamin C is significant (P
