Abstract: A method of combating arthropods, comprising applying to the arthropods, or to a habitat infested therewith an arthropodicidally effective amount of an antibiotic which (a) is colorless, very readily soluble in water and in pyridine but insoluble in other customary organic solvents, gives a positive reaction with ninhydrin, sodium metaperiodate/benzidine and potassium permanganate and gives a yellow coloration with iron (III) chloride, (b) has the UV and IR spectra substantially as shown in FIGS. 1 and 2, (c) on chemical degradation yields uracil, an amino-hexuronic acid and an amino-acid containing a pyridine ring, (d) on paper electrophoresis proves to be an amphoteric substance and has an isoelectric point at about pH 6 and (e) consists of the elements carbon, hydrogen, oxygen and nitrogen, or one or more active components of the antibiotic mixture, the active agent being applied alone or in admixture with a diluent or carrier.

Abstract: Bafilomycins of the formula ##STR1## in which R.sup.1 is hydrogen or CH.sub.3, andR.sup.2 is hydrogen, or the group ##STR2## are produced by culturing certain streptomyces, e.g. Tu 1922, Tu 2437 and Tu 2599. Those wherein at least one of the OH groups is acylated are new. The compounds are pesticidally active.

Abstract: Pesticidally active substantially pure nikkomicin fractions obtained from Streptomyces tendae Ettlinger et al Tu 901, the fractions being selected from the group consisting of ##STR1## a mixture of nikkomicin I and J, and a mixture of nikkomicin M and N.

Abstract: A method of combating arthropods, comprising applying to the arthropods, or to a habitat infested therewith an arthropodicidally effective amount of an antibiotic which (a) is colorless, very readily soluble in water and in pyridine but insoluble in other customary organic solvents, gives a positive reaction with ninhydrin, sodium metaperiodate/benzidine and potassium permanganate and gives a yellow coloration with iron (III) chloride, (b) has the UV and IR spectra substantially as shown in FIGS. 1 and 2, (c) on chemical degradation yields uracil, an amino-hexuronic acid and an amino-acid containing a pyridine ring, (d) on paper electrophoresis proves to be an amphoteric substance and has an isolectric point at about pH 6 and (e) consists of the elements carbon, hydrogen, oxygen and nitrogen, or one or more active components of the antibiotic mixture, the active agent being applied alone or in admixture with a diluent or carrier.