| Pollen is extraordinary nutritious and survival of honeybee colony is totally linked to its ability to collect sufficient quantities of pollen from plants'flower. As well different research findings indicated that pollen is the richest source of different nutrients that are important to human health. However, its nutrient absorption is highly limited due to the hard outer wall of pollen grain. Therefore, in order to maximize the nutritional release of pollen, it is necessary to break its hard outer wall.In this study, rape pollen was treated with papain, cellulose, hemicellulase, pectinase in different temperature and pH. Furthermore, enzyme assisted with ultrasonic were also studied. Permeability of germ pores was evaluated with several parameters, such as protein dispersion and dissolution index, soluble sugar, microscopic examination, scanning electron microscope, grading analysis.Even if the pollen was not completely broken, it was possible to improve the germ pores permeability with enzymatic hydrolysis. Among those enzymes, papain exhibited best effect of enzymatic hydrolysis at the temperature of 60℃, pH6.0, and 20 hours. Under this condition, protein dispersion index 0.7753, dissolution index 0.5587, and the content of soluble sugar 25.48% was obtained. After 4 hours enzymolysis, the surface of pollen became smooth, and the structure of extine was easily visibleand the germ pores were open to 1.11μm. The germ pores size were found positively correlated to the time of enzymolysis. After 20 hours of enzymolysis, the contents of pollen cell dissolved from three germ pores whose size increased to 5.28μm. However, germ pores size increased to 8.75μm after 32 hours enzymolysis and presented trivalve dehiscence. We can clear visualize the outer surface of extine.Interestingly, the intine was still intact film post the extine shed and the pollen cell was tuft after pollen was treated just with ultrasonic. As a result, the nutrition was not dissolved. The treatment with papain assisted with ultrasonic registered best result. The pollen grains split along the germ pores, all the contents dissolved. The optimal parameters were ultrasound power 800W, ultrasound time 270min, pH6.0,ultrasound temperature 60℃. Under this condition, the protein dispersion index 0.9893, the protein dissolution index 0.5725, the content of soluble sugar 22.57%, and the ratio of wall-broken 66.36% was obtained.Wall-broken pollen is a process in which pollen cell was crushed into fragments by some treatment on the pollen, the contents were all dissolved. And it is not really wall-broken pollen when only the germ pores opened. Pollen wall-broken is in the regulation that breaking along the germ pore. The rape pollen was treated by the method of enzyme hydrolysis assisted with ultrasonic wave, the pollen cell wall splited absolutely due to cavitation, emulsification, agitation, enzyme specifity. The ratio of wall-broken was the percentage of obtrite pollen number in the total number. The fragments number was 3 times of that of obtrite pollen.The effect of wall-broken could be directly reflected by microscope, environmental scanning electron microscope, and scanning electron microscope. It was easy to visualize the figure of extine through scanning electron microscope. According to wall-broken through the wall-broken ratio and grading analysis, the effect of wall-broken can be displayed use figures. The protein solubility index, the dispersed index, and the contents of soluble sugar could indicate nutrition dissolution from the point of nutrient. Combined with multiple parameters, the effect of wall-broken was evaluated from macroscopic to microscopic perspective, and was proved to be a scientific evaluation method.
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