Abstract: The seed embryos of Isatis indigotica Fort were exposed to He-Ne laser (5.23 mW/mm2, radiated for 5 min) and microwave (1.26 mW/mm2, radiated for 8 s) irradiation to determine the effects of microwave and He-Ne laser pretreatment on enzyme activities, and biophoton emission of cotyledon. Then: (i) changes in the activities of enzymes in I. indigotica cotyledon (such as amylase, transaminase, and proteinase) were measured to investigate the effects of He-Ne laser and microwave pretreatment; and (ii) biophoton emission was measured to determine the speed of cell division and metabolism. Results from these experiments indicated that: (i) the activities of amylase, transaminase, and proteinase of the cotyledon pretreated by He-Ne laser and microwave were significantly increased; and (ii) the intensity of biophoton emission was enhanced significantly by He-Ne laser and microwave irradiation. These changes suggest that He-Ne laser and microwave pretreatment can improve the inner energy of seeds, lead to an enhancement of cotyledon enzymes, and speed up the metabolism of the cell, resulting in significantly increased biophoton emission. Moreover, the mechanism of action of the effects of laser and microwave radiation on the microcalorimetric parameters, enzyme activities, and biophoton emission of seeds is discussed on the basis of the results obtained.

Key words: biophoton emission, enzymes activities, Isatis indigotica, laser, microcalorimetric effect, microwave.