Biological Effects Of Wheat Processed By High Pressure Treatment

The research aim to find out and analysis the wheat's physiological activities after high pressure(HP)treatment. Select different varieties of wheat according to different gluten strength, analysis the wheat'protein and starchs micro-structure in using SEM. Build a Pressure-Time model to treat wheat seeds and test the germinating ability through germination experiment. On this basis, get the HP treatment parameters. And then test the amylase activities in using 3,5-dinitrosalicylic acid colorimetry, test the peroxidase activity in using guaiacol method and peroxidase isozyme electrophoresis, test the catalase activity in using permanganate titration and test the wheat seed's membrane permeability under Pressure-Time model in using conductivity method and evaluate the wheat's stress resistance, try to find the liner relationship of wheat's germination rate and membrane permeability. The wheat's physiological activities and protein and starch's micro-structure was obviously changed by high pressure treatment. We get conclusions as follows.(1) HP treatment can destroy the protein's reticular formation which in the endosperm and can also strength the systematization of protein. HP treatment can separate the starch grain which encapsulated in protein and make the amount of free starch grains increase.The protein present pore structure. Big starch grains can be crushed and volume reduced by HP treatment, the starch grains long and minor axis were shorten by HP treatment in varying degrees.(2) The Pressure-time model was significant to different varieties of wheat's germination power and germination rate, the pressure leading to the loss of the ability of wheat germination, the higher the pressure, the germination energy and germination rate is lower. The wheat seeds which can also germinate after HP treatment shows a weak growth vigor compare with CG.(3) The amylase activity of wheat which treated by HP is lower than CG on the first 1-3 days and began to increase to flat or even beyond on the follow 4-6 days. Peroxidase activity of HP treated wheat was increased compared with CG, after drought stress, Peroxidase activity of HP treated wheat also higher than CG. The effect of HP treatment on wheat catalase activity was not obvious.(4) Cell membrane permeability tests showed that HP treated wheat seed cell membrane is damaged, the permeability increased. The Pressure-time model on the different varieties of wheat cell membrane permeability were all highly significant, reflecting the higher the pressure, the greater the membrane permeability. Membrane permeability and germination rate of wheat was negatively correlated.(5) Continuous heating conductivity in testing the wheat's drought resistance show that, after high pressure treated wheat seeds, the inflection point temperature was no change compared with CG, that means HP treatment did not cause the drought resistance of wheat significantly affected.