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In the electroreduction of carbon dioxide, catalytic activities of the tetrasulfonated metal phthalocyanines(MeTSP) homogeneously dissolved in the Clark–Lubs buffer solutions were investigated by the measurements of current- and capacitance-potential curves. It was found that CoTSP and NiTSP were active but not CuTSP and FeTSP.

Under novel conditions of culture, Streptomyces lavendulae No. 314 was found to produce new antibiotics, chlorocarcins and mimosamycin in addition to streptothricin. The antibiotics are extracted from culture filtrate with organic solvents and further purified by silica gel chromatography. Chlorocarcins A, B, and C are closely related basic antibiotics which are active against gram-positive bacteria , EHRLICH carcinoma and L 1210 leukemia of mice. Mimosamycin is a neutral antibiotic which is mainly active against mycobacteria. Production, isolation and physicochemical properties of the antibiotics are described.As the new sources of streptomycetes and streptoverticillia starting to dwindle , the chances to find new antibiotics seem to have become increasingly poor, and a current screening techniques among streptomycetes often lead to known substances. On the other hand, the application of more sensitive and selective detection techniques has continued to provide new and interesting antibiotic substances. A sensitive and rational antitumor cell screening system was developed recently in our laboratory employing suspension culture of L 1210 murine leukemia cell line.') During the course of the antitumor cell screening using this system, the culture filtrate of a strain of streptomyces, designated as No. 314, was found to be cytocidal and antibacterial with activity against Bacillus subtilis and Escherichia coli. The major antibiotic produced by the strain in a submerged state under regular culture conditions proved to be a streptothricin complex') which apparently is devoid of antitumor activity. During the study of the detailed culture conditions for the production of satellite antibiotics of streptothricin, our group have isolated mimosamycin, an antibiotic which is mainly active on mycobacteria including streptomycin-resistant strains of human tubercle bacilli and three antitumor antibiotics, chlorocarcins A, B, and C. This paper describes the production of these antibiotics and their physicochemical characterization. Antibiotic ProductionThe organism used in this investigation was Streptomyces sp. No. 314 which was later identified as a strain of Streptomyces lavendulae.3) The culture was maintained in the lyophilized state. A freshly grown slant on glucose-asparagine agar (KRAINSKY) was used for the inoculum of laboratory-scale antibiotic production. Laboratory fermentation was run in 500-ml shake