The adsorption behaviour and reaction mechanism of oxamyl with acid and base saturated montmorillonites were investigated with the help of adsorption isotherms, Freundlich constants, thermodynamic parameters, IR and X-ray spectroscopy. Adsorption data were analysed, applying the linear form of the Freundlich equation. A qualitative assessment of the nature of the reaction was made with the help of these measures. Effect of temperature and different cations was also studied. The values of the equilibrium constant and standard free energy change pointed to the higher affinity of oxamyl for montmorillonite surface, and that the adsorption was in the order Na->H->Ca-montmorillonite. The exothermic nature of interaction indicates that the adsorption phenomenon of oxamyl on the montmorillonite surface occurred through a bonding mechanism. The data indicate the existence of protonation and/or coordination between the exchangeable cation of the montmorillonite and oxygen of the amide group of oxamyl molecule.

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Glucosyltransferase produced by Streptococcus salivarius HHT was purified from the culture filtrate, and its enzymic properties were examined. The enzyme was specific to sucrose (Km 7.2mM), and formed a water-insoluble α-D-glucan consisting of a high proportion of (1 → 3)-α-D-glucosidic linkage (90%) together with small proportions of (1 → 6)- and (1 → 4)-α-D-glucosidic linkages. The optimum pH and temperature of the enzyme activity were 5.8 and 40°C, respectively. The enzyme activity and yield of the water-insoluble glucan were stimulated in the presence of dextran. The addition of low molecular weight oligosaccharides, such as maltose and isomaltose, inhibited the production of the water-insoluble glucan with the concomitant formation of several oligosaccharides, i.e., O-α-D-glucopyranosyl-(1 → 6)-O-α-D-glucopyranosyl-(1 → 4)-D-glucopyranose (panose), O-α-D-glucopyranosyl-(1 → 3)-O-α-D-glucopyranosyl-(1 → 4)-D-glucopyranose, maltotriose, and O-α-D-glucopyranosyl-(1 → 6)-O-α-D-glucopyranosyl-(1 → 6)-O-α-D-glucopyranosyl-(1 → 4)-D-glucopyranose.

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A Bacillus subtilis strain, 207-SV1, producing thermostable α-amylase was constructed by transformation as reported previously using a nonhomologous DNA prepared from an unidentified and Gram negative thermophilic bacterium, Thermophile V2. In the study here, enzymatic characterization of an extracellular thermostable α-amylase was conducted in comparison with B. subtilis α-amylase. Both α-amylases were found to be equally insensitive to 5mM EDTA but differed from each other in thermostability, optimum temperature, electrophoretic mobility on polyacrylamide gel, and immunological specificity. These results suggest that the structure of the thermostable α-amylase was different from that of the B. subtilis α-amylase. The structural gene for the thermostable α-amylase was named amyV2⁺. PBS1 phage mediated transduction and DNA mediated transformation studies with 207-SV1 and its derivative strains suggested that the chromosomal order around amyV2⁺ was recA-pyrA-cysC-amyV2-metC. Since the amyV2⁺ locus differs from that of amyE⁺, DNA from B. subtilis strain B7, which has a tunicamycin-resistant mutation (tmr7) located close to amyE, was transferred into strain 207-SV1, and transformants producing both thermostable α-amylase and B. subtilis α-amylase were isolated.

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A β-cyanoalanine (β-(-CNAla)-forming enzyme, which catalyzed the formation of β-CNAla from O-acetyl-L-serine and sodium cyanide, was isolated in crystalline form from Enterobacter sp. 10-1, a cyanide-resistant strain. The purification procedure involved protamine treatment, ammonium sulfate fractionation, column chromatography on DEAE-cellulose, DEAE-Sephadex A50, Sephadex G-100 and hydroxyapatite, and crystallization with ammonium sulfate. The crystalline enzyme was homogeneous by criteria of the ultracentrifugation and polyacrylamide gel electrophoresis.
The enzyme was determined to have a molecular weight of about 68, 000, and consisted of two apparently identical subunits, each having a molecular weight of about 34, 000. The enzyme also catalyzed the formation of cysteine from O-acetyl-L-serine and sodium sulfide, and the cysteine-forming activity was 245 times greater than that of the β-CNAla-forming activity.

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The properties of a purified β-cyanoalanine (β-CNAla)-forming enzyme isolated from Enterobacter sp. 10-1 were studied.
It has been found previously that this enzyme catalyzed the formation of cysteine from O-acetyl-L-serine and soldium sulfide, as well as the formation of β-CNAla from O-acetyl-L-serine and sodium cyanide.
The affinity of the enzyme for sodium sulfide in the formation of cysteine was one order of magnitude greater than that for sodium cyanide in the β-CNAla formation. In addition, the optimum pH, pH- and thermal stability of β-CNAla-forming activity were similar to those of cysteine-forming activity. The results of the studies indicated that the β-CNAla-forming enzyme of Enterobacter sp. 10-1 was an O-acetylserine sulfhydrylase catalyzing the formation of cysteine from O-acetyl-L-serine and sulfide. The solution of the enzyme was yellow and exhibited an absorption peak at 420 nm. The enzyme itself contained approximately 1 mol of pyridoxal phosphate per 34, 000 g of protein.

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N-Carbobenzoxy-L-phenylalanyl-aminohexyl-Sepharose (Z-Phe-AH-Sepharose) was found to be an effective affinity adsorbent for neutral proteinase from Streptomyces naraensis. This enzyme was adsorbed on this affinity column at pH 7.0 or higher, and eluted with 0.3 M NaCl in starting buffer. The resulting enzyme appeared homogeneous on disc electrophoresis and showed considerably higher specific activity and recovery than by previous method.

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Ethoxyformic anhydride and photooxidation were used to study the function of histidine residues in neutral proteinase from Streptomyces naraensis. Ethoxyformic anhydride completely inactivated the enzyme. However, NH₂OH reactivated the ethoxyformic derivative to 100% of the value of the enzyme treated with only 40mM NH₂OH. Since NH₂OH specifically deacylates Nethoxyformylimidazole, it was shown that at least some of the histidine residues were essential for the activity. In addition, photooxidation experiments in the presence of 0.001% rose bengal confirmed that only histidine residues of the enzyme were destroyed under the designated experimental conditions. About two histidine residues per 37, 000g of protein were destroyed during the photooxidation experiments. In the presence of the competitive inhibitor carbobenzoxy-L-phenylalanine, ∗ only one histidine residue was destroyed, which inhibitor, that one histidine residue per 37, 000g of protein was essential for the enzyme activity.

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A thermophilic strain, No. 1023, of Acetobacter aceti was isolated, by which it became possible to carry out submerged vinegar production at 35°C. The thermophilic property of the strain correlated closely with its acetic acid resistance. Strain No. 1023 lost acetic acid resistance at high frequency (more than 55% in isolated strains) and lost ethanol oxidizing ability at lower frequency (about 40%) compared to the above in the stationary growth phase in a liquid medium containing ethanol. The loss of these properties during the stationary phase was confirmed using a genetically marked strain (pro^-) of No. 1023. Such frequent loss of acetic acid resistance and ethanol oxidizing ability suggested a relationship between these properties and a plasmid. A plasmid, pTA 5001, was found in strain No. 1023, and its molecular weight was determined to be 17 × 106 daltons by electron microscopy. The plasmid, however, seemed to have no direct connection with acetic acid resistance or ethanol oxidizing ability, because the same plasmid was found in all strains which had no these properties.

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6-Phospho-D-gluconate dehydrogenase (EC 1.1.1.44) was purified and crystallized from a cell free extract of Gluconobacter suboxydans IFO 12528. Affinity chromatography on a blue-dextran Sepharose 4B column was effective through the purification steps, and a 280-fold purification was achieved with a 56% yield. The crystalline enzyme was homogeneous, as judged by polyacrylamide gel electrophoresis and analytical ultracentrifugation. Although the enzyme from G. suboxydans catalyzed the oxidative decarboxylation of 6-phospho-D-gluconate to D-ribulose-5-phosphate, it differed from enzymes derived from other sources in respect to substrate specificity and molecular properties. Unlike the others, this Gluconobacter enzyme has a requirement for similar amounts of NAD and NADP as coenzymes and the pH optimum of this protein with two coenzymes was samely 6.5, while other enzyme preparations have the optimum pH at 8.0. The molecular weight of this enzyme was 175, 000, and the enzyme was composed of four identical subunits of molecular weight 43, 000. The enzyme activity was inhibited competitively by ATP, D-fructose-1, 6-diphosphate and NAD(P)H. It was shown that the NADPH formed by the action of the enzyme was reoxidized by the old yellow enzyme of the organism.

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The circular dichroism (CD) and absorption spectra of the ternary system, lutein-ovalbuminlipid, were studied in relation to the previously reported novel optical activity acquired when lutein formed a complex with some proteins [Agric. Biol. Chem., 44, 2111 (1980); 45, 1159 (1981)]. The CD spectrum of the system varied markedly with the amount of lipid added. On molar basis, the effect of the lipids tested decreased in the order of oleate and elaidate-linoleate-lecithin, while laurate has no effect. The observed phenomena may be interpreted in six ways, (a) the primary action of the added lipid is to remove lutein from the lutein-ovalbumin complex, (b) the complex between lutein and the lipid thus formed shows a CD qualitatively similar to but quantitatively different from that of the lutein-ovalbumin complex, (c) such CD can be observed with a lutein-lipid complex in which the latter is achiral, and thus can be ascribed to the presence of oligomeric aggregates of lutein with a chiral nature in mutual orientation, (d) the lipids act only as solubilizing agents of the aggregates, (e) the presence of two or more kinds of different optically active species in the ternary system produces the apparently complicated CD spectra, (f) the optical activity disappears completely and once the absorption spectrum of lutein is blue-shifted, it returns to the normal pattern when all lutein molecules are solubilized monomerically into micelles of lipid now abundant from the excess addition.

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Resting cells and acetone-dried cells of Corynebacterium sp. S-401 catalyzed the fatty acid ester synthesis of various alcohols and fatty acids. These reactions were carried out in phosphate buffer and/or organic solvents. In some cases synthetic reactions of esters in nonpolar solvents, such as n-hexane and benzene, gave better results compared with those obtained in phosphate buffer.

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Bicyclic phosphates (BPs), GABA antagonists, were prepared by reaction of the corresponding triols with phosphoryl chloride. The triols were obtained by one of the following methods: (a) the Tollens condensation of an aldehyde possessing α-hydrogen atoms with formaldehyde; (b) the basecatalyzed hydroxymethylation of alkylmalonates or α-alkylacetoacetates with paraformaldehyde, followed by reduction; (c) the reduction of diethyl pivaloylmalonate; or (d) the halogenation of pentaerythritol. Some BPs were also derived by modification of the functional groups of BP homologs. The ¹H-NMR spectra of 4-substituted BPs showed a characteristic doublet peak due to the endocyclic methylene protons, the shift position of which was affected by the electronic nature of the bridgehead substituent. The mass spectra of the PBs were characterized by peaks due to the loss of CH₂O from the ring.

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The necessary factors for making the characteristic aroma of Katsuobushi were investigated. The aromas, obtained from various heat treatments of several materials, were compared with the aroma of Katsuobushi using a sensory test, pattern similarity analysis of GC profiles and GC-MS data. The oil and meat of bonito and the smoking process were considered significant among several factors in the Katsuobushi manufacturing process. However extracted residue and oil of Katsuobushi, i.e. the protein-rich and oil fractions, contained only a trace of Katsuobushi aroma, the mixture of these two materials had a Katsuobushi-like aroma after heating with smoke oil as a substitute for the smoking process. The similarity in the aroma qualities between the obtained Katsuobushi-like and genuine Katsuobushi aromas was confirmed by comparing the aroma components and GC profiles of both aromas.

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Steam-volatile components of roasted and air-dried chicory root were investigated. Thirty-two compounds were identified in the roasted root, 23 of which were new as chicory root constituents. The major components of the air-dried root were fatty acids (palmitic, 60.2% and linoleic, 31.5%). The same acids and the corresponding methyl esters were found in large quantities in the roasted root. In addition, the following compounds were identified as major components in the roasted root: vanillin, 5-hydroxymethyl-2-furfural, 2-acetylpyrrole, furfural, phenylacetic acid, 2-(5-hydroxymethyl-2-formylpyrrol-1-yl)-3-methylpentanoic acid lactone and phenylacetaldehyde.

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The relationships between dietary levels of the essential amino acids and hepatic polysome profiles of rats were investigated with special attention to the amino acid requirement pattern for the maximum rat growth as determined by other investigators. The basal diet contained a 7% essential amino acid mixture and a 3% non-essential amino acid mixture, with appropriate amounts of other nutrients. Rats were fed test diet for 5 hours and then the polysome profile was determined. The amounts of essential amino acids needed for maximum aggregation of polysome were low for methionine-cystine, leucine and tryptophan as compared with requirements for maximum growth. But in other essential amino acids, the amounts were in almost the same range as those reported for maximum growth by others. The differences between the amino acid requirement patterns for maximum aggregation of hepatic ribosomes and for maximum growth of rats might be due to a difference in amino acid requirements of the liver and whole body. Therefore, the hepatic polysome profile might be used to measure the effect of amino acid supplementation on dietary proteins. The requirement pattern of essential amino acids in other organs may be studied by polysome profile determination.

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The tension values were determined for milk curds formed by six protéases using a curd tension meter. In curds with relatively high tension values, which were prepared by rennet, Mucor rennin and pepsin (acid proteases), α_s- and β-casein were negligibly hydrolyzed during incubation after clotting, whereas both casein fractions in the fragile curds prepared by Alkaline-protease from Bacillus subtilis, trypsin and thermolysin (alkaline proteases) were electrophoretically degraded during further incubation after clotting. This phenomenon was more prominent in the β-casein fraction. However, when alkaline proteases were employed in an immobilized form and removed from the test-milk at the initiation of clotting, the degradation of β-casein was decreased, and curd tension values were increased. Inhibition of the enzymatic degradation of β-casein by addition of sodium chloride (5%) led to an increase in curd tension. When the test-milk treated by each immobilized alkaline protease was fortified with β-casein, curd tension value increased significantly. These results suggest that β-casein might be essential for the hardening of curd.

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The protoplast fusion of Mucor pusillus and M. miehei was studied to develop a breeding system for the microbial rennin-producing Mucorales fungi. High yeilds of protoplasts from young germlings of these fungi were obtained by using an enzyme system containing Streptomyces No. 6 chitosanase, a commercial chitinase and sulfatase. Approximately 1 - 10% of these protoplasts regenerated on a solid medium with a soft agar overlay. Intraspecific hybridization between M. pusillus strains, as well as interspecific hybridization between M. pusillus and M. miehei was brought about by protoplast fusion, in the presence of polyethylene glycol in rather high frequencies (5-40%). Several hybrid strains between (+) and (-) strains of M. pusillus showed stable homothallic properties.

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The glycoprotein nature of soluble peroxidase isolated from the tomato fruit was established using Schiff's reagent after periodic oxidation. This enzyme retained on a concanavalin A Sepharose column was eluted using an α-methyl-D-mannoside gradient. On including this step in the purification scheme, the tomato peroxidase was purified 263-fold with a yield of 63%. The enzyme so obtained was homogeneous on polyacrylamide gel electrophoresis and its RZ value was 2.8.

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The in vitro digestibility of rice glutelin and wheat glutenin was investigated with a view to assessing their nutritional qualities, using casein and bovine serum albumin (BSA) as references. The following hydrolytic processes were adopted: pepsin-pancreation digestion (a model system before intestinal absorption) and aminopeptidase-prolidase hydrolysis [a model system for the intestinal mucosa (membrane digestion) and after intestinal absorption (intracellular hydrolysis)]. The pepsin-pancreatin digests were first examined. The degree of amino acid released from the proteins was 30% (glutelin), 23% (glutenin), 24% (casein) and 30% (BSA). A similar release pattern of individual amino acids was observed for all the proteins. The amounts of large peptide fractions increased in the order: glutelin < glutenin < casein < BSA. Glutelin was highly digestible. Apart from containing high amounts of glutamic acid (glutamine), cystine and proline, the large peptide fractions of glutelin were also rich in threonine, glycine and isoleucine while those of glutenin were only rich in glycine. The aminopeptidase-prolidase digests were examined next. Glutelin was almost completely hydrolyzed to amino acid, except for a low release of cystine, suggesting that the amino acid residues constituting glutelin could be easily utilized as nutrients in the living tissues. The degree of amino acid released from the proteins was 97% (glutelin), 93% (glutenin), 90% (casein) and 79% (BSA).
The convenient application of these model systems for the assessment of the in vitro digestibility of food proteins have been discussed.

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Washed cells of facultative methylotrophs which have the serine pathway showed high activities for L-methionine formation from DL-homocysteine, in the presence of methanol as methyl donor. Strain FM 518, isolated from soil and identified as a bacterium belonging to the genus Pseudomonas, showed the highest activity for L-methionine formation and was used as the parental strain for breeding the L-methionine-producing mutants. An ethionine-resistant mutant, FE 244, derived from strain FM 518, accumulated 0.8 mg/ml L-methionine in a methanol-medium under optimum conditions.

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Starting from (S)-2, 2-dimethyl-l, 3-dioxolane-4-ethanal, all four Stereoisomers of 16-heptadecene-1, 2, 4-triol were synthesized. In comparison with synthetic products, the naturally occurring antibacterial triol in the avocado fruit was determined as (2R, 4R)-16-heptadecene-1, 2, 4-triol.

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Mutants resistant to growth inhibition by DL-3, 4-dehydroproline, an analog of L-proline, were derived from the wild type L-glutamate producing bacteria, Brevibacterium flavum, Brevibacterium lactofermentum, Corynebacterium glutamicum and Microbacterium ammoniaphilum. Among these mutants, potent L-proline producers were obtained.
The production of L-proline by Brevibacterium flavum No. 199, which was obtained as an isoleucine auxotrophic and sulfaguanidine resistant mutant from the wild strain, was improved by deriving DL-3, 4-dehydroproline resistant mutants under the condition, in which the overproduction of L-proline was reduced by adding excess L-isoleucine, i.e. more than necessary for growth. Among mutants thus obtained, strain P-390 produced 40 g of L-proline per liter, which was 30% more than that of parental strain No. 199, in medium containing 10% glucose, 6% ammonium sulfate, inorganic salts and other components. This yield was the highest among yields so far reported.

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Brevibacterium flavum No. 2247 was found to grow with L-glutamate as the sole carbon and nitrogen source on an agar-plate medium when high concentrations of L-glutamate, FeSO₄ and biotin were added to the medium. It grew on L-glutamate in liquid medium only when yeast extract or high concentrations of FeSO₄ and glucose or organic acids of the tricarboxylic acid cycle were added to the medium. The growth on L-glutamate in liquid medium was also stimulated by high concentrations of L-glutamate, biotin and MgSO₄, and inhibited by a high concentration of (NH₄)₂SO₄.
Aspartate aminotransferase (TA)- and α-ketoglutarate dehydrogenase (KD)-defective mutants did not grow on L-glutamate, and glutamate-utilizing revertants derived from these mutants recovered TA and KD activity, respectively, whereas glutamate dehydrogenase (GD)-defective mutants grew on L-glutamate. Washed cells of strain No. 2247 grown on glutamate decomposed the amino acid, whereas those grown on glucose did not. The degradation was observed only under aerobic conditions. The former cells showed higher KD, succinate dehydrogenase and fumarase activities than the latter cells. Of 75 mutants which did not grow on glutamate but grew on succinate, three strains lacked KD but showed the same glutamate productivity as the parent strain. Four other strains with normal KD levels showed higher glutamate productivity than the parent.

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The specific activities of three B₁₂-dependent enzymes in Rhizobium meliloti were compared in relation to morphological changes in the bacterium. The critical levels of ribonucleotide reductase and methylmalonyl-CoA mutase seemed to be maintained, while the level of methionine synthase was probably insufficient for cell multiplication. A close relationship was observed between the methionine synthase level and morphological changes in the bacterium. The addition of folate with methionine to the cobalt-deficient medium did not have a positive effect on bacterial growth. A sufficient amount of tetrahydrofolate was detected in the cobalt-deficient elongated cells. These findings might suggest the important role of methionine synthase in cell multiplication, which was unpredictable from the methylfolate trap hypothesis.

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A variety of long-chain fatty acylamino analogs of N-acetylmuramoyl-L-alanyl-D-isoglutamine (MDP), such as N-(acyl)muramoyl-dipeptides (1) and N-acetyl-6-(acylamino)-6-deoxymuramoyl-dipeptides (2), were synthesized to examine their immunological activities. All the N-(acyl)muramoyl-L-alanyl-D-isoglutamines (1) were active as adjuvant on the induction of delayed-type hypersensitivity to azobenzenearsonate-N-acetyl-L-tyrosine in guinea pigs. N-(3-Hydroxy-2-tetradecyloctadecanoylamino)muramoyl-L-alanyl-D-isoglutamine (1d) and N-acetyl-6-deoxy-6-(3-hydroxy-2-docosylhexacosanoylamino)murarnoyl-L-alanyl-, -L-valyl-, and -L-seryl-D-isoglutamines (2) showed antitumor activity by suppressing tumor (Meth-A fibrosarcoma) growth in syngeneic BALB/c mice.

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The resting cells of a 2-deoxystreptamine idiotrophic mutant of Micromonospora sagamiensis were found to transform sisomicin into gentamicin C_1a and sagamicin. The biotransformation products were isolated by a combination of ion exchange and carbon column chromatographic procedures, and properly identified. Antibiotic G-52 (6'-N-methylsisomicin) was not detected in the transformation products. Gentamicin C_1a was formed at an early stage of the biotransformation, followed by sagamicin formation. The (4', 5')-reduction of sisomicin may occur first, followed by 6'-N-methylation. By use of a similar procedure, it was demonstrated that verdamicin was transformed into gentamicin C_2a (the 6'-C epimer of gentamicin C₂), C₂, and then C₁. Carbon TLC clearly separated gentamicin C_2a, C₂, and verdamicin. In this biotransformation, the (4', 5')-reduction of verdamicin occurred first, followed by 6'-C-epimerization, and then 6'-N-methylation.
In contrast with M. sagamiensis, M. zionensis NRRL5466 and M. inyoensis NRRL3292 did not possess any detectable activity of the (4', 5')-reduction of sisomicin or verdamicin. Alternatively, NRRL5466 transformed sisomicin into antibiotic G-52, and verdamicin into a new antibiotic, VF3-1. The antibiotic VF3-1 was suggested as 6'-N-methylverdamicm by chromatographic and mass spectrum data. The implications of these findings were discussed in relation to sagamicin biosynthesis in M. sagamiensis.

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Five L-fucose-specific lectins which were produced by Streptomyces were compared with a L-fucose-specific lectin, SFL 16-3, which was produced by Streptomyces no. 16-3 [T. Kameyama, K. Oishi and K. Aida, Biochim. Biophys. Acta, 587, 407 (1979)]. Except for SFL 374, their blood group specificity was similar to that of SFL 16-3, which preferentially agglutinates human blood group O erythrocytes. SFL 374 did not distinguish O erythrocytes from B erythrocytes. Except for SFL 194, they were similar in moelcular weight, isoelectric point and amino acid composition, and serologically cross-reactive with each other. SFL 194 had an exceptionally large molecular weight and was not cross-reactive, although it was quite similar in amino acid composition. Taxonomical properties of the Streptomyces strains producing these lectins were correlated with the properties of the lectins.

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The oxygen-resistant hydrogen bacterium, N34, was cultivated in ajar fermentor continuously fed a gas-mixture of various tension of H₂, O₂ and CO₂. Cell growth with a doubling time of 4hr was achieved with a gas-mixture of 70%H₂+20%O₂+10%CO₂ or 50%H₂+40%O₂+10%CO₂ even from the early stage of culture. The distribution of hydrogenase activity in cells grown under 40% O₂ was examined by separating the crude extracts into soluble and particulate fractions, and the hydrogenases seemed to be bound to the membranes. The oxyhydrogen reactions were not particularly stable under high oxygen tension in intact cells, crude extracts and particulate fractions of oxygen-resistant hydrogen bacterium, N34, compared with those of oxygen-sensitive strain.

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The effects of tropomyosin and troponin on the heat-induced gelation of myosin were investigated by SDS-polyacrylamide gel electrophoresis, scanning electron microscopy and gel rigidity assay, in comparisons with natural and desensitized actomyosin. SDS-polyacrylamide gel electrophoretograms revealed that tropomyosin was almost completely removed from each desensitized actomyosin samples while it was retained in natural actomyosin samples. In spite of this, no significant differences were found in rigidity between natural and desensitized actomyosin gels. No differences could be observed in the microstructure of either actomyosin gel. It may, therefore, be concluded that tropomyosin does not affect the gel texture of the actomyosin system.

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Corynebacterium equi IFO 3730, which had previously been demonstrated to be capable of assimilating 1-hexadecene, also showed good growth on 1-hexadecen-11-ol (1a). The corresponding ketone, 1-hexadecen-11-one (2a) was isolated as the product from the broth. This microorganism-mediated oxidation has been revealed to have a wide applicability, and a variety of sec-alcohols were oxidized to the corresponding ketones in good yields on incubation with the bacterium grown on 1-hexadecene as a sole source of carbon.

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Two new metabolites exhibiting an inhibitory activity against the development of sea urchin embryos were isolated from the culture of Aspergillus candidus Link. The structures of the compounds, candidusin A and B, were determined on the basis of chemical and spectroscopic means. Candidusin B inhibited DNA and RNA synthesis but not protein synthesis.

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