1. Using house flies to detect pesticide residues in vegetables

In the late 1960s, the Taiwan Agricultural Experimental Institute used bioassay methods to test pesticide residues. The principle was to release highly sensitive house flies into vegetable juices. , if the housefly mortality rate is less than 10 after 4 to 5 hours, it is considered qualified. This method is simple and does not require complex instrument testing. The disadvantage is that the detection time is long, it only reacts to some pesticides, and it is impossible to distinguish the type of residual pesticides and is accurate. Lower sex.

2． Using Daphnia magna as the test material to monitor pesticide residues in vegetables

The principle of this method is to dilute vegetable juice according to ISO standards, 10 Daphnia per dose, and measure the experimental results at 24h, 48h, and 96h , using the heart of the experimental water flea to stop beating as the final death indicator, to determine the 50% lethal concentration. Yuan Zhenhua et al. have conducted exploratory research on this type of determination method. The research shows that the Daphnia magna testing technology is fully suitable for the determination of pesticide residues in vegetables. They believe that this method is fast, sensitive, simple, economical, etc., but this method is also It is impossible to tell the type of residual pesticide.

3. Use luminescent bacteria to detect pesticide residues

Luminescent bacteria are a type of non-pathogenic common bacteria that can emit blue-green visible light with a wavelength of 490nm under normal physiological conditions. This luminescence phenomenon is the result of bacterial metabolism and is a side branch of the respiratory chain. When luminescent bacteria come into contact with substances that interfere with and damage metabolism, especially toxic and harmful substances, the luminous intensity of the bacteria can be reduced or extinguished, and the concentration of poisons and the luminous intensity of bacteria change in a negative linear relationship. This feature can be used to measure pesticide residue samples. Yuan Dongxing and others used luminous bacteria to detect pesticide residues, and the minimum detection concentration was 3mg/L. This method has been used to detect commonly used organophosphorus pesticides such as methamidophos and dichlorvos.

Luminous bacteria can produce luminescence-inhibited reactions to multiple poisons at the same time, but the linear relationship between pesticide concentration and luminous intensity is not accurate enough. After the luminous bacteria are activated, their luminous intensity will change with time. . It is fast, simple, sensitive and cheap, and has gradually shown its advantages in qualitative and semi-quantitative on-site rapid detection. With the development of the food industry, the use of luminescent bacteria to detect food safety has gradually attracted widespread attention as a rapid primary screening method.