Gamma irradiation of Sennae Folium. Microbiological and phytochemical studies.

The effect of different doses of gamma irradiation on senna leaves was studied. No changes in sennoside content and composition were observed after irradiation with 25 kGy. It was demonstrated that a minimum dose of 10 kGy was necessary to obtain a product of good microbiological quality. Cold maceration of senna leaves has to be discouraged, because of unavoidable microbial growth. Hot extraction is the method of choice for tea preparation. The rationale of gamma irradiation is discussed.