In an earlier report1), the isolation and properties of tylosin were described. In the fermentation which produces tylosin, other antibiotics are synthesized and can be detected on bioautograph plates after paper chromatography of the broth filtrate. This paper decribes the fermentation, isolation, physicochemical properties, and biological activities of macrocin, a second antibiotic found in the culture broth which produces tylosin. Lactenocin, a microbiologically active substance, can be prepared by the degradation of macrocin.
In our search for new antibiotics from microscopic fungi several hundred strains of fungi were isolated from soil and other natural sources in Slovakia1), in Bulgaria2) and in China3). All strains were tested for their antibiotic activity and some “ecological factors” were observed in relation to their antibiotic properties.
Recently we have published results of our studies on the antibiotic activity of 213 strains of fungi of the genus Penicillium, Aspergillus, Fusarium and other genera, which had been isolated from soil samples from Indonesia4). In this paper we are presenting results of more detailed studies of the biological activity of 75 strains from the same collection. Thirty strains belong to the genus Penicillium, 26 to the genus Aspergillus and 19 to others.
Antibacterial, antifungal, antiprotozoal and antinematodal activity of the crude concentrates prepared from cultivation media and from mycelia of these strains were studied.
In a previous peper1) we have published data about antibacterial, antifungal, antiprotozoal and antinematodal activities of crude concentrates obtained from the cultivation media and from the mycelia of 75 strains of fungi isolated from soils in Indonesia2). The crude concentrates containing antibacterial and antifungal antibiotics were further studied by paper chromatography elaborated by Betina3). for a systematic analysis of antibiotics.
Results of these studies are described in this paper. Data on the paper chromatographic classification of antinematodal antibiotics from the same collection of strains of fungi will be published later.
In the course of our search for new antibiotics, a Streptomyces species indexed Z-452 in our culture collection has been found to produce a mixture of antibiotics. When grown in a suitable medium, at least four different antibiotics are produced. When the mycelium is separated from the broth by filtration, one of the antibiotics, which belongs to the actinomycin-type judging from the summarized paper-bioautography6) and electrophoretic paper-bioautography,7) is present primarily in the mycelium mat whereas the other three antibiotics, one of which belongs to the macrolide-type and two belong to the unknowntype junging from the avove mentioned paper-bioautographys, are present principally in the filtrate.
The antibiotic with which this invention is one of the unknown-type that is extracted from the filtrate, which has been obtained in a white needle crystalline form.
Streptomyces Z-452 has been isolated from a soil sample obtained Shōdo Island, Kagawa Prefecture. The crystalline antibiotic, which we have named showdomycin, exhibits particularly high reactivity in vitro against Streptococcus hemolyticus and, moreover, it shows a remarkable inhibitory effect on Ehrlich ascites tumor in mice.
The purpose of the present paper is to describe the antibiotic-producing organism and to report preliminary studies on production, isolation, antimicrobial spectrum, anti-tumor activity and properties of showdomycin.
In the course of searching for new anti-viral antibiotics from actinomycetes using mouse-poliovirus system, a new antibiotic designated as julimycin B-II was isolated from Streptomyces shiodaensis nov. sp.1)
The isolation method, the physical and chemical properties, and some of the biological properties of this antibiotic are described in this paper.
In a screening of biguanide derivatives for antiviral activity, we found several compounds to inhibit the multiplication of poliovirus in tissue culture. We are reporting here the effect of one of the compounds, N1,N1-anhydrobis (β-hydroxyethyl)-N5-(p-toluenesulfonyl) biguanide (SB-184)1) on poliovirus infection in mice.
Many reports dealing with the activity of antibacterial antibiotics which induce the morphological changes of bacteria were published. Among them, it was well known that penicillin inhibited cell division and induced morphological changes such as elongation, filament formation, diplococcus-like linking and enlargement of the cells of Escherichia coli and Staphylococcus. However, regarding with such activities of antitumor substances, the experiments with mitomycin3), azaserine2) and phleomycin4) were only issued. At the 16th General Meeting of Japan Medical Society, in April 1963, we reported that iyomycin1), a new antitumor substance isolated from a soil-streptomyces caused a remarkable elongation of growing cells of Escherichia coli strain B.
In connection with the interesting activity of iyomycin, we performed similar experiments with other available substances comprising chemicals and antibiotics. And we found that many chemotherapeutic agents might be classified into 3 major groups and 6 types based upon the induced morphological changes of E. coli B. The present paper will deal with a classification of the chemotherapeutic agents based on the morphological change of E. coli B.