Folic Acid in Axenic Cultures of Neoaplectana

Abstract

Neoaplectana glaseri, a nematode parasite of insects, needs folic acid for reproduction. This has been shown in axenic cultures by omitting the vitamin from chemically defined medium or including antimetabolites such as aminopterin and amethopterin in a meat infusion broth. Bacterial assays for folic and folinic acids show quantitative changes in various media inoculated with N. glaseri and two other parasitic species which do not thrive as well in liquids, N. dutkii and N. carpocapsae. Folic acid is included in a chemically defined medium for axenic cultures of the nematode Neoaplectana glaseri Steiner, 1929, in nature a parasite of certain insects (Glaser and Fox, 1930). But this roundworm's actual requirement for the vitamin has not been studied quantitatively either in chemically defined solutions or in media from natural sources. While detailed data on nutrition are not of tremendous interest by themselves, they may be crucial in context of our total knowledge about both parasite and host, and in comparison with other species. Consequently, liquid media, inoculated with N. glaseri or one of two related species, were titrated for amounts of folic acid and a biologically active derivative, folinic acid. Effects of antimetabolites and absence of folic acid were also