RADIOLYSIS OF HERBS

Radiolysis of 124 types of herbs was studied. The majority were stable under gamma-irradiation with absorbed dose up to 10 kGy. Radiolytic d ecomposition was detected at 10 kGy for 16 types of herbs (12.9%) and at 5 kGy for 6 types (4.8%). No detectable radiolytic decomposition wa s found at <2 kGy. The model system study showed: 1, gamma-radiolysis is different from thermohydrolysis and photolysis; 2, water adsorbed o n herbs evidently affects the radiolytic decomposition of herbs. Pulse and gamma-radiolysis of baicalin, 1,8-dihydroxyanthraquinone-beta-D-g lycoside, glycyrrhizin and corydalic-B showed that some new compounds were formed due to the attack of OH radical. The addition of fructose and glucose can inhibit the gamma-radiolytic decomposition of herbs. C hemical clearance displays fruitful and hopeful prospect to disinfect herbs by gamma-ray, but important measure and step should be adopted. That is: 1, the herbs must exist in dry state; 2, it is preferred to m ake bolus by mixing powdered Chinese medicine and honey, as the latter can inhibit the radiolysis of herbs; 3, the producer must pay attenti on to executing strictly manufacture procedure to reduce the microbiol ogical contamination, thus subsequently lower the applied dose.