Effect of GaAlAs laser irradiation on enzyme activity.
OBJECTIVE
The aim of this study was to determine the influence of laser irradiation on enzyme activity.


BACKGROUND
Enzymes are catalysts of extraordinary efficiency, able to accelerate reactions by manifold. Enzyme laser light activation is currently a fast-growing field and a large number of studies have been produced.


METHODS
Liquid CNPG amylase and control serum (Qualitrol 1H) were used in the experiments. Laboratory analysis of alpha-amylase was performed on two sample groups: (i) E + S and (ii) E + S + L, in six repetitions per irradiation dose. Group 2 was irradiated with gallium-aluminum-arsenide (GaAlAs) 904 nm at doses of 0.01, 0.1, 0.5, and 1 J/cm(2). Enzyme activity was read using a spectrophotometer equipped with a thermostatic chamber capable of precise absorbance measurement at 405 nm.


RESULTS
The results were analyzed with the Student's t-test, and the percentage of enzyme activity was determined. Photomodulation of alpha-amylase activity by GaAlAs laser was analyzed following irradiation with different doses. Irradiation doses from 0.01 to 1 J/cm(2) led to differences in enzyme activity: 0.01 J/cm(2) (0.10%), 0.1 J/cm(2) (13.44%), 0.5 J/cm(2) (12.57%), and 1 J/cm(2) (-6.10%).


CONCLUSIONS
Irradiation doses of 0.1 J/cm(2) and 0.5 J/cm(2) led to statistically significant increases in enzyme activity in comparison to the control. The similar curves of the effects of temperature and pH on enzymatic activity observed in this study suggest that laser irradiation also possess an optimum dose to modulate the enzymatic activity. That is, enzymes have an optimum laser dose (or range) at which their activity is maximal, whereas at higher or lower doses activity decreases.
Laboratório de Biologia Celular & Tecidual, Instituto de Pesquisa & Desenvolvimento, UNIVAP, São José dos Campos, Brazil. nsoares@univap.br
Newton Soares
NS
Da Silva
Juliana W
JW
Potrich
D004307:Dose-Response Relationship, Radiation; D004789:Enzyme Activation / Q000528:radiation effects; D057075:Enzyme Assays; D006801:Humans; D054023:Lasers, Semiconductor; D009596:Nitrophenols / Q000378:metabolism; D013054:Spectrophotometry, Atomic; D000516:alpha-Amylases / Q000032:analysis / Q000528:radiation effects*
D009596:Nitrophenols; D000516:alpha-Amylases; C548837:2-chloro-4-nitrophenol