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Homoalanosine having a herbicidal activity was isolated from the culture filtrate of a soil isolate SC-1688 which was classified as Streptomyces galilaeus. The chemical structure of homoalanosine was determined to be L-2-amino-4-nitrosohydroxyaminobutyric acid by analyses of spectral and biological data. The antibiotic has high herbicidal activity at low concentrations against especially commoncocklebur and ladysthumb amongthe tested weeds and crops. Foliar application of this antibiotic inhibited the growth of roots and buds. This result indicated that homoalanosine had a systemic herbicidal activity.In the course of our screening for new herbicidal antibiotics, we found that a soil isolate SC-1688 collected at Gonohe, Aomori Prefecture, produced an active material, homoalanosine.Physicochemical, NMRand biological studies of homoalanosine revealed that its chemical structure was L-2-amino-4-nitrosohydroxyaminobutyric acid. Although the racemate of this antibiotic had already been chemically synthesized0 as a homolog of alanosine2) and its insecticidal activity had been also reported50, its isolation from natural sources and herbicidal activity have not been reported. This paper deals with the taxonomy of the producing strain and fermentation, purification procedures, structure determination, herbicidal activity and mechanism of action of homoalanosine. Materials and MethodsInstruments IR, NMRand secondary ion (SI)-MS spectra were recorded on a Hitachi IR spectrophotometer Model 270-30, a Varian NMRspectrometer XL-200 and a Hitachi M-80B mass spectrometer, respectively. Heteronuclear multiple bond correlation spectroscopy (HMBC) spectrum was recorded on a Jeol JNM-GX-500 spectrometer. A scanning electron micrograph was obtained with an electron microscope Hitachi S-430. Screening ProceduresActinomycetes isolated from soil samples were inoculated in Erlenmeyer flasks (200 ml) containing 60 ml of the screening medium consisting of soluble starch 3.0%, yeast extract 1.0%, NaCl 0.3 % and CaCO30.3% (pH 7.2). After cultivating for 4 days at 28°C on a rotary shaker (150rpm), broth filtrates were sprayed onto leaves of 1-week old radishes. The treated radishes were kept at 202 8°C for 2 weeks. Herbicidal activity was examined through a visual observation of the damaged area.Homoalanosine has been reported in Jpn. Kokai 259593 ('87), Nov. ll, 1987.

ABSTRACT. This study was designed to develop a novel culture method for the efficient proliferation of canine peripheral blood lymphocytes (cPBL) for adoptive immunotherapy. When cPBL were cultured in the presence of concanavalin A (Con A), proliferation of cPBL was induced and expression of interleukin-2 receptor (IL-2R) which enables to respond to exogenously added IL-2 was upregulated. And then, when cPBL were cultured with recombinant human interleukin-2 (rhIL-2) in addition to Con A, proliferation was accelerated and increased to about 10-fold after 1 week. The phenotypic analysis showed that the main population of the cultured cPBL was consisted of CD8+ positive lymphocytes. Among them, CD4+CD8+ double positive (DP) lymphocytes had significantly increased, and the ratio of CD4+ single positive (SP) lymphocytes to CD8+ SP lymphocytes (CD4+SP/CD8+SP) was decreased as compared to before culturing. To evaluate the cytotoxic activity of cPBL cultured with Con A and rhIL-2, furthermore, cytotoxic assay was carried out against xenogeneic melanoma cell line (MeWo), which resulted in MHC-unrestricted cytokilling. These results suggest that the culture method of cPBL by the use of Con A and rhIL-2 may be useful for generating lymphokine activated killer cells, and also this may be beneficial for adoptive immunotherapy of tumor-bearing dogs.