[Direct selection of Aspergillus terricola variants having different toxicity on a culture of fibroblasts]. / Priamoi otbor variantov Aspergillus terricola s razlichnoi toksichnost'iu na kul'ture fibroblastov.

A direct method is proposed to select less toxic mutants of Aspergillus terricola on a culture of fibroblasts. The conidia are first irradiated with UV, and then are used to grow colonies on the glass surface of tubes or flasks containing medium 199. The cells of fibroblasts are added thereupon and the two cultures are being grown together for 24--48 hours. The colonies which inhibit the growth of fibroblasts to a less extent are selected using microscopy. The method can be used for primarily selection of experimentally produced mutants of Aspergillus which form fibrinolytic enzymes possessing low toxicity.