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A9145is a new adenine-containing antifungal antibiotic. A9145showedweakin vitro activity against Candida albicans in Sabouraud's medium, but was strongly inhibitory in a chemically defined medium. Viability counts of C. albicans following extended exposure to A9145 indicated a fungistatic action. Following a lOOmg/kg dose, a peak of64^g/ml of A9145 activity was detected in mouse blood. Administration of 10 mg/kg for 3 days extended the survival time of mice infected with C. albicans 128 % ; equivalent doses of amphotericin B extended survival time \\2%. A total dose of 31.25mg/kg administered over a 5-day period reduced by 400-fold the number of Candida recovered from kidney homogenates of infected mice. A combination of amphotericin B and A9145 caused a possible synergistic effect against C. albicans in vitro and an additive effect in vivo.

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The dry-heat resistance of Bacillus subtilis var. niger spores located in or on various materials was determined as D and z values in the range of 105 through 160 C. The systems tested included spores located on steel and paper strips, spores located between stainless-steel washers mated together under 150 inch-lb and 12 inch-lb of torque, and spores encapsulated in methylmethacrylate and epoxy plastics. D values for a given temperature varied with the test system. High D values were observed for the systems in which spores were encapsulated or under heavy torque, whereas lower D values were observed for the steel and paper strip systems and the lightly torqued system. Similar z values were obtained for the plastic and steel strip systems (ZD = 21 C), but an unusually low z for spores on paper (ZD = 12.9 C) and an unusually high z for spores on steel washers mated at 150 inch-lb of torque (ZD = 32 C) were observed. The effect of spore moisture content on the D value of spores encapsulated in water-impermeable plastic was determined, and maximal resistance was observed for spores with a water activity (a,) of 0.2 to 0.4. Significantly decreased D values were observed for spores with moisture contents below a, 0.2 or above a, 0.4. The data indicate that the important factors to be considered when measuring the dry heat resistance of spores are (i) the initial moisture content of the spore, (ii) the rate of spore desiccation during heating, (iii) the water retention capacity of the material in or on which spores are located, and (iv) the relative humidity of the system at the test temperature.