Thirty-nine coffee samples (32 arabica and 7 robusta coffees) were classified objectively by two kinds of multivariate analysis (quantification theory 3 and cluster analysis) of sensory data. A cup test was done with respect to seven terms: acidic, sweetish, grassy aroma; earthy odor; robusta odor; off-flavor; and total amount of aroma. Robusta coffees were separated from arabica coffees by quantification theory 3 and cluster analysis of the 39 coffee samples. The aroma profiles of the 32 arabica coffee samples were also characterized by quantification theory 3. By cluster analysis of the scores of the first, second, third, and fourth axes obtained by quantification theory 3, the 32 arabica coffee samples were divided into seven clusters. Consequently, 39 coffee samples were classified into eight groups reflecting the information from the cup test.

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The aroma profiles of 39 coffee samples (32 arabica and 7 robusta coffees) were evaluated objectively by the coupling of gas chromatographic analysis and two kinds of multivariate analysis (principal component analysis and cluster analysis) and compared with the classification on the basis of a cup test of brewed coffee by cup testers. Robusta coffees were separated from arabica coffees by principal component analysis (PCA) and cluster analysis. Using PCA of only 32 arabica coffee samples, their aroma profiles could be characterized on the first and second principal components. The components responsible for grassy aroma and earthy odor, respectively, were clarified from the factor loadings obtained by PCA. Furthermore, 32 arabica coffees were divided into seven clusters by cluster analysis of the first and second principal components obtained by PCA. Consequently, 39 coffee samples were classified into eight groups and the result was consistent with the classification on the basis of sensory evaluation except for two samples.

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An ice-nucleating bacterium, strain KUIN-1, was isolated from the leaves of field beans (Phaseolus vulgaris L.). Strain KUIN-1 was identified as Pseudomonas fluorescens from its taxonomical characteristics. Ice-nucleating activity was obtained when strain KUIN-1 was cultured aerobically in a medium containing Koser citrate broth (pH 7.0) for 24 hr at 18°C. The icenucleating activity did not appear until the bacterial cell concentration reached 10⁷ to 10⁸/ml. Nucleation at - 3.0°C was detected in suspensions (1.8 × 10⁹ cells/ml) of cells that had been grown on the medium containing Koser citrate broth. Strain KUIN-1 produced a lower nucleation frequency (i.e. the number of ice nuclei/cell) than did ice-nucleating Pseudomonas syringae No. 31 suspensions, particularly at temperatures above - 5°C. The nucleation frequency of strain KUIN-suspensions was similar to that obtained for an ice-nucleating Erwinia herbicola No. 26 at - 5°C.

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The oxidation of black tea components such as theaflavin, theaflavin monogallates, and theaflavin digallate by partially purified polyphenol oxidase from tea leaves in the presence and absence of equimolar concentrations of (-)-epicatechin was studied in model fermentation experiments under aerobic conditions. The oxidation of theaflavin monogallates was more rapid than that of theaflavin digallate, which was very slow. (-)-Epigallocatechin was not effective in oxidizing theaflavin components, instead it prevented their oxidation.

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Extraction of oil from rice bran with supercritical carbon dioxide (SC-CO₂) at pressures of 150 to 350 kg/cm² G at 40°C was demonstrated. The constituents of the selective fractions obtained at different pressures differed. Fractions obtained at higher pressures contained less free fatty acid and waxes or unsaponifiables. The phosphorus and iron contents were very low in the SC-CO₂ extracted oil, while the color of the oil was significantly lighter than that of hexane-extracted oil. The yield of low acid value oil was comparable to that for hexane extraction. One problem of the SC-CO₂ oil is its poor oxidation stability. This method of extraction may be effective in simplifying the processing of edible rice bran oil. Grinding the raw material was found to be effective in decreasing the CO₂ required and shortening the extraction period.

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The regulatory mechanism for L-tryptophan (L-Trp) synthesis was compared between the wild type strain and L-Trp producing mutants of B. subtilis K. In the wild type strain, indolmycin (IM) repressed the synthesis of anthranilate synthetase (AS) more strongly than 5-fluorotryptophan (5FT), which repressed AS to the same extent as L-Trp did. 5FT inhibited the activity of AS as strongly as L-Trp did, while IM had no inhibitory effect. In the 5FT resistant strains, the syntheses of AS and tryptophan synthetase (TS-B) were markedly increased by genetic derepression, while AS remained still sensitive to the feedback inhibition by L-Trp. The facts that IM repressed the syntheses of AS and TS-B in the strain which was 5FT^r and IM^s, and did not repress those in the IM-resistant mutant suggested that IM acts as a co-repressor in a different way from 5FT.

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The regulatory properties of 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase (DS) and chorismate mutase (CM) were compared between L-Trp-producing mutants and the wild-type strain of Bacillus subtilis K. The synthesis of DS in the L-Trp producers was elevated 6- to 13-fold compared to that in the wild-type strain, however, its synthesis was still repressed when the mutants were cultured in the presence of L-Phe and/or L-Tyr. The DS from the L-Trp-producers was still sensitive to inhibition by chorismate and prephenate. The specific activity of the CM in the L-Trpproducers was only 3% of that in the case of the wild-type strain, which was due to the loss of activity of the CM 1-type enzyme and which contributed to the derepression of DS and the higher L-Trp accumulation.

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Azaserine (AzaSer) and 6-diazo-5-oxo-L-norleucine (DON), which are glutamine antagonists, strongly inhibited the activity of anthranilate synthetase of Bacillus subtilis K. Mutant strains AJ 11980 (AzaSer^r) and AJ 11981 (AzaSer^r, DON^r) showed increased accumulation of L-Trp compared with the parent strain, AJ 11979 (5FT^r, IM^r). Furthermore, we obtained from AJ 11981 mutant, AJ 11982, resistant to cinnamate, which was shown to block the common pathway of aromatic amino acid biosynthesis. AJ 11982 accumulated 13.6 g/1 of L-Trp from 130 g/1 of glucose in a flask culture. We optimized the conditions for large-scale cultivation of this mutant and L-Trp accumulation of 21.5 g/1 was attained using ajar fermentor.

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Structure breaking anions, triehloroacetate (-TCA^-) and thiocyanate (-SCN^-), significantly increased the interaction between <κ>K-casein (K-C) and β-actoglobulin (B-Lg) to give the covalently stabilized K-C/B-Lg tetrameric (A4) complex, whereas "structure making" anions, chloride (-Cl^-) and especially sulfate (-SO₄^-), reduced it. The reactivity of K-C with B-Lg in the presence of these anions followed the order, -TCA^->-SCN^->-Cl^->-SO₄^- (100 mM). The percentile distribution of the covalent bonded K-C/B-Lg A4 complex after 720 s of heating at 70°C in -TCA^- (100 HIM) was one order greater than it was in -SO₄^-. During storage of the heated K-C/B-Lg mixture, the B-Lg A3/K-C interaction in -TCA^- was rapid and uneffected by the holding temperature, whereas in -SO₄^-, the reaction rate was inversely related to the temperature, being apparently controlled by the relative concentration of monomeric K-C.

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As new kairomone components, 2-palmitoyl- (I) and 2-stearoylcyclohexane-1, 3-dione (II) were identified for the parasitic wasp Venturia canescens from feces of the Indian meal moth larva, Plodia interpunctella. One more component, 2-arachidoylcyclohexane-1, 3-dione (III), together with the afore mentioned two compounds were newly obtained from feces of the almond moth larva Cadra cautella.
Purified kairomone fractions from both species indicated similar activity to synthetic 2-oleoylcyclohexane-1, 3-dione (active at 0.1mg/ml). 2-Palmitoylcyclohexane-1, 3-dione (I) was the most active (at 1 mg/ml) among the synthetic homologues with saturated 2-acyl groups.
No traces of 2-acylcyclohexane-1, 3-dione were found in the rearing medium of the host; therefore, the kairomone was suggested to have been biosynthesized.

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The aggregation between lysozyme and heat-denatured ovalbumin was investigated by measuring the development of turbidity. The obtained aggregates were found to consist of lysozyme and ovalbumin at the molar ratio of 1.5, from the result of electrophoretic analysis.
The aggregation was inhibited by the addition of NaCl or the acylation of lysozyme. This result suggests that the lysine residues in lysozyme were directly involved in the aggregation process. It is suggested that the cysteine residues in ovalbumin did not participate in the aggregation with lysozyme. The degree of aggregation reached its maximum when the ovalbumin solution was heated to 75°C, and was suppressed by the association of ovalbumin molecules during heat denaturation. From these results, it was found that lysozyme interacted electrostatically with the monomeric molecule of fully unfolded ovalbumin during aggregation.

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Water-soluble wine-colored pigments, rhodonocardins A and B (RN-A and -B), were isolated along with antibiotic sakyomicins from the culture broth of Nocardia sp. Mild acidic hydrolysis of RN-A gave (+)-rhodinose and RN-B. The CMR data suggested RN-A and -B to be glycosides of the same aglycone as that of sakyomicin A, except for the presence of a hydroxy group on C(5). The structures of RN-A and -B were determined as Ia and Ib, respectively, both of which contain a 1-α-deoxy-2-mercaptoglucosyl moiety on C(5).

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The cells of Hydrogenobacter thermophilus strain TK-6 contain only a membrane-bound hydrogenase. The membrane-bound hydrogenase was partially purified from the cells of H. thermophilus after solubilization by alkaline treatment. The hydrogenase activity was increased up to 10-fold by the addition of anionic detergents. The hydrogenase reacted with cytochrome c₅₅₂ obtained from the same strain in the presence of an anionic detergent. Our experiments show cytochrome c₅₅₂ is a natural electron acceptor for the membrane-bound hydrogenase, and an electron transport system in H. thermophilus strain TK-6 is proposed.

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Methylotrophic bacteria, isolated from soil samples or from sewage sludge, proved to be useful sources of esterases for catalyzing the enantioselective hydrolysis of racemic N-acetyl-indoline-2-carboxylic acid methyl ester (7) to the corresponding (2S) or (2R)-N-acetyl amino acid (6) with high optical yields. From the DMF-utilizer Pseudomonas DMF 5/8 and the methanol-utilizer Isolate EE 210, the corresponding esterases were isolated. Reactions with whole cells as well as with the purified enzymes are described.

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When an aqueous alkaline solution of curdlan in the stationary state was neutralized with carbon dioxide, it became a firm gel with slight syneresis, the resultant gel showing high syneresis when freeze-thawed. This gel behavior differed from that of the gels obtained by heating an aqueous suspension of curdlan at high temperatures. The dried matter obtained by pressing the unheated gel to remove the water could be regenerated into a gel by soaking it in water. Curdlan powder, which was obtained by crushing the dried matter, was found to be a good material to form a gel. However, curdlan powder obtained from gels that were formed by heating an aqueous suspension of curdlan could not produce a good gel. An electron microscopic study showed no significant difference between the preparations of original curdlan and the gels formed by neutralizing its alkaline solution.

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The conversion of (-)-cis-carveol and (+)-cis-carveol by Streptomyces bottropensis SY-2-1 and S. ikutamanensis Ya-2-1 was investigated.
S. bottropensis SY-2-1 transformed (-)-cis-carveol mainly to (+)-bottrospicatol [(4R, 6R, 8R)-(+)-6, 8-oxidomenth-1-en-9-ol] (1), with (+)-isobottrospicatol [(4R, 6R, 8S)-(+)-6, 8-oxidomenth-1-en-9-ol] (2) as one of the minor products. On the other hand, strain SY-2-1 transformed (+)-cis-carveol mainly to (-)-isobottrospicatol (4), with (-)-bottrospicatol (3) as one of the minor products. S. ikutamanensis Ya-2-1 metabolized the cis-carveols in the same way into bottrospicatols.
The metabolic pathways for (-)-cis-carveol and (+)-cis-carveol in S. bottropensis SY-2-1 and S. ikutamanensis Ya-2-1, and the biological activities of bottrospicatols are described in this paper.

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The glutathione (GSH)-dependent degradation of salithion, which is one of the effective insecticides against Organophosphate (OP)-resistant housefly (Musca domestica L.), and that of the ineffective insecticides, fenitrothion and malathion, was studied. The most degradable insecticide was malathion (22% and 97% with susceptible SRS and OP-resistant 3-Y homogenates, respectively), then fenitrothion (9% and 26%), and the least was salithion (3% and 9%). Ethacrynic acid inhibited the in vitro degradation of all three OP-insecticides by both SRS and 3-Y homogenates, and lowered the degradation level to the same as that existing under conditions without the addition of GSH. 2-Methylthio-l, 3, 2-benzodioxaphosphorin 2-oxide, a thiolo-isomer of salithion, and O, O-diisopropyl S-ring-hydroxy-benzyl phosphorothiolates (hydroxy IBPs) inhibited the degradation of fenitrothion. The former also inhibited the carboxylesterase-dependent degradation of malathion.

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Transglucosylation of an α-glucosidase (I) from honeybee was investigated. The honeybee α-glucosidase catalyzed the predominant formation of α-1, 4-glucosidic linkage from sucrose, phenyl α-glucoside, or maltose. The major product from sucrose was 4^G-α-glucosyl-sucrose (erlose), which differs from the report by Huber and Thompson that 3^F-α-glucosyl-sucrose (melezitose) is mainly synthesized from sucrose by the transglucosylation of the same α-glucosidase: Biochemistry, 12, 4011 (1973). Melezitose was not detected as the transglucosylation product of this enzyme.

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When a galactanase from Penicillium citrinum was incubated with HgCl₂ in the presence of KCl, mercury bound to the enzyme at one g atom per mol. The modified enzyme had increased activity on o-nitrophenyl-β-D-galactopyranoside (ONPG) compared to the native enzyme and there was no more increase in the activity with further treatment with HgCl₂. The activity of the modified enzyme on soybean arabinogalactan and o-nitrophenol-substituted galactooligosaccharides, on the other hand, decreased to 70-80% of that of the native one. The modified enzyme had the same UV spectrum, molecular weight, isoelectric point, and CD spectrum as those of the native enzyme.
Mercury bound to the modified enzyme could be removed by dialysis against a reduced glutathione solution and the activity on ONPG of the enzyme reverted to that of the native one, indicating the reversibility of the modification.

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The production of prochymosin directed by a cloned cDNA under the control of a trp promoter was examined in E. coli C600 and HB101. The latter host exhibited a higher degree of expression as to the production of prochymosin in the form of inclusion bodies, which accounted for more than 15-20% of the total cellular protein. The conditions for the processing of prochymosin in the inclusion bodies to active chymosin were determined. Several enzymatic properties of the processed bacterial chymosin, such as its specific activities as to milk-clotting and proteolysis, heat stability and Ca²⁺ dependence of the clotting activity, were almost identical to those of authentic chymosin. However, a slight difference was observed with regard to the immunological reactivity with anti-prochymosin antibody.

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A Carboxylesterase that hydrolyzes ML-236B (compactin) to ML-236A (ML-236B esterase) has been extracted from mycelia of Emericella unguis and purified to homogeneity by successive ammonium sulfate fractionation, chromatography on DEAE-cellulose, gel filtration on Sephadex G-75 and preparative gel electrophoresis. The molecular weight of the purified enzyme was found to be -40, 000 and its optimum pH to be around 8. Of the p-nitrophenylesters with different C-chain lengths tested, p-nitrophenylbutyrate (C₄) was the best substrate for the enzyme. Since ML-236B is an α-methylbutyryl ester of M1-236A, the data suggest that the E. unguis esterase is highly specific for the C₄-chain length. β-Naphthylacetate, tributyrin, olive oil and casein were not hydrolyzed. The ML-236B esterase was sensitive to N-ethylmaleimide and the organophosphate, DDVP, but resistant to eserine (carbamate), NaF and EDTA.

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The "stopped-flow time difference analysis" technique (a novel and sensitive technique, involving a sort of end-point assay using the stopped-flow method) was applied to the modified biuret method (micro-biuret method) for protein determination. Protein concentration was easily determined from a reaction curve recorded for only 2 sec. The calibration curve for bovine serum albumin was linear from zero to 1000 μg/ml. The detection limit for bovine serum albumin was 4 μg/ml and is comparable to that of the widely used Lowry method. The important advantage of the present method, compared with the conventional spectrophotometric methods, is that it was much less affected by the variation of protein species, and was almost free from interference by coexisting materials, including widely used tris(hydroxymethyl)aminomethane and peptides. The method is thus useful for a sensitive and accurate determination of either an unknown individual protein or total proteins in an aqueous solution.

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The activities of 2-oxoaldehyde-metabolizing enzymes (glyoxalase I, glyoxalase II, methylglyoxal reductase, methylgjyoxal dehydrogenase and lactaldehyde dehydrogenase) were found to be widely distributed among microorganisms. One of the enzymes, methylglyoxal reductase, which catalyzes the reductive conversion of methylglyoxal into lactaldehyde, was purified from Escherichia coli cells. The enzyme was judged to be homogeneous on polyacrylamide gel electrophoresis and was a monomer with a molecular weight of 43000. The enzyme was most active at pH 6.5 and 45°C. The enzyme utilized both NADPH and NADH for the reduction of 2-oxoaldehydes (glyoxal, methylglyoxal, phenylglyoxal and 4, 5-dioxovalerate) and some aldehydes (glycolaldehyde, D, L-glyceraldehyde, propionaldehyde and acetaldehyde). The Km values of the enzyme for methylglyoxal, NADPH and NADH were 4.0mM, 1.7μM and 2.8 μM, respectively. The product of methylglyoxal reduction was identified as lactaldehyde. The enzyme from E. coli cells was different from the yeast and goat liver enzymes in both molecular structure and substrate specificity.

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Glutathione thiol esterase activity in cell extracts of a yeast: Saccharomyces cerevisiae was separated into three peaks when filtered on a Sephadex G-150 gel column. One of the enzymes in these peaks was purified. The enzyme was a single polypeptide chain with a molecular weight of 28, 000 and catalyzed the complete hydrolysis of S-acetylglutathione and S-lactoylglutathione. S-Methyl-, S-hexyl-, S-glyceryl-, S-succinylglutathiones, and acetyl CoA were not hydrolyzed. In addition to the hydrolytic activity, the purified enzyme showed a group transfer activity and catalyzed the formation of acetyl CoA from S-acetylglutathione and CoA. The purified enzyme was not identical with glyoxalase II in molecular weight, substrate specificity, or behaviors toward inhibitors.

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(22R, 23R, 24S)-3α, 5-Cyclo-22, 23-diacetoxy-5α-ergostan-6-one (2b) is a new key intermediate of some naturally occurring brassinosteroids such as brassinolide (1a), castasterone (1b), teasterone (1c) and typhasterol (1d). The cycloketone 2b was prepared in 10 steps via (22R, 23R, 24S)-6β-benzyloxy-3a, 5-cyclo-22, 23-dihydroxy-5α-ergostane (5) from stigmasterol. 2b was treated with a catalytic amount of p-toluenesulfonic acid and sodium bromide to give an enone (7b), which was oxidized with osmium tetroxide and derived to give a 2α, 3α-acetonide (8b). 8b was easily separated from its isomer by the use of silica gel column chromatography. 8b was oxidized with trifluoroperacetic acid and deacetylated to give 1a. 8b was deacetylated and deacetonized to give 1b. 2b was treated with dilute sulfuric acid in acetic acid to give a 3β-acetate (10). 10 was treated with sodium hydroxide to give 1c. 2b was treated with hydrobromic acid to give a 3β-bromide (12), which was treated with silver acetate to give a 3α-acetate (13). 13 was treated with sodium hydroxide to give 1d.

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4-Chloro-2-butynyl N-(3-chlorophenyl)carbamate (Barban) is a herbicide whose alkaline hydrolysis leads quantitatively to 3-chloroaniline, after releasing the chlorine atom from the ester group. The dechlorination step proceeds via a nucleophilic substitution reaction of the type S_N2-S_N2', corresponding to an attack by hydroxide ion at the carbon atoms that are α and γ to the chlorine atom. The 4-hydroxy-2-butynyl and 2-oxo-3-butenyl N-(3-chlorophenyl)carbamates thus formed are hydrolysed to the N-(3-chlorophenyl)carbamic acid which, on decarboxylation, gives 3-chloroaniline.

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Changes of protein components (LA, LB, LC, and X) in mouse serum after administration of an antitumor agent, LC 9018 (lyophilized preparation of Lactobacillus casei, YIT 9018), were investigated. The intraperitoneal injection of LC 9018 caused an increase in these proteins one or two days after administration. The LC component was purified from mouse serum and was identified as haptoglobin. In addition, LA was identified as an intermediate of a haptoglobin-hemoglobin complex [Hp-Hb(α¹β¹)] and X as a haptoglobin-hemoglobin complex [Hp-Hb(α²β²)] because addition of increasing amount of hemoglobin to purified haptoglobin formed X via LA and all of these components were immunoprecipitated with anti-haptoglobin IgG.

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Enzyme activities involved in the initial step of glycerol metabolism were determined in cells of methylotrophic yeasts grown on glycerol, methanol or glucose. In Candida boidinii (Kloeckera sp.) No. 2201, the activities of glycerol kinase and dihydroxyacetone kinase were detected in cells grown on glycerol and methanol, respectively. The activity of NAD⁺-linked glycerol dehydrogenase of Hansenula polymorpha DL-1 was induced by glycerol and methanol, while that of Hansenula ofunaensis was induced by glycerol. The enzymes of both strains were subject to catabolite repression by glucose.
The yeasts tested were divided into three groups as to the glycerol dissimilation patterns. Strains of the genera Candida, Saccharomyces, Pichia and Torulopsis had the phosphorylative pathway, in which glycerol is first phosphorylated. H. ofunaensis had the oxidative pathway, in which glycerol is first oxidized. H. polymorpha DL-1 had both the phosphorylative and oxidative pathways.

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Prior to an analysis of the shrinkage and growth of air bubbles entrained in wheat flour dough, the shrinkage and growth under a temperature rise of a small bubble in water was analysed for comparison. The rates of shrinkage and growth of the bubble were respectively controlled by the diffusion of under- and over-saturated dissolved air from and into the bubble. The diffusion coefficient of the dissolved air in water calculated from the shrinkage of the bubble was 2.10×10^-9m²/sec (17°C), which agrees with the literature value. On the other hand, at below 100°C, the effects on the bubble growth of the expansion of air due to the temperature rise and the increase in the saturation vapor pressure of water were negligibly small. The accompanying air entrained in flour particles suspended in water was much more stable than a free bubble in water. However, the growth under a temperature-rise of a bubble evolved from wheat flour particles was the same as the growth of a bubble in water, if many bubbles did not coexist.

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In order to investigate the relationship between taste-blindness and its chemical structure, sensory tests on thioureas, guanidines, imidazoles and thiazoles, which are widely used as vulcanizing agents for rubber, were carried out. It was found that new compounds, which had an intermediate characteristic between bitter and taste-blind substances, were present in benzimidazole and benzothiazole compounds. When it is considered that these compounds have structural similarities and only slight structural changes were present in them, these results provide an indication of the bitter exhibition mechanism on a taste receptor.

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1-Pyrroline-5-carboxylate dehydrogenase was purified and crystallized from Bacillus sphaericus. The crystalline preparation gave a single band on polyacrylamide slab gel electrophoresis. The molecular weight of the enzyme was determined to be about 100, 000 by gel filtration. The enzyme consists of two subunits which are identical in molecular weight (50, 000), as judged on SDS slab gel electrophoresis. The enzyme shows an optimum pH of 6.5 to 7.0. Its activity was 8.1 times higher with NADP⁺ than with NAD⁺, and the enzyme was stabilized by NADP⁺. The apparent Km values for L-l-pyrroline-5-carboxylate, NADP⁺ and NAD⁺ are 4.2×10^-5M (with NADP⁺), 9.5×10^-6M and 2.5×10^-3M, respectively. The enzyme reaction is irreversible. A simple method for the determination of L-ornithine involving ornithine δ-aminotransferase and 1-pyrroline-5-carboxylate dehydrogenase from B. sphaericus was developed. A linear relationship was found between the absorbance at 340nm and the amount of L-ornithine (50-400nmol), and between the fluorescence and the amount of L-ornithine (0.2-10nmol).

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The Hill-reaction inhibitory activity of 30 derivatives of 2-difluoromethylthio-1, 3, 5-triazine was determined using chlorella. The structure-activity relationships were analyzed using the hydrophobic parameter (log P), the electronic substituent constant (σ) and the steric substituent constant (Es). The Hill-reaction inhibitory activity showed a parabolic relationship to log P and the steric substituent parameters at 4, 6-dialkylamino' positions in the triazine ring. The equation revealed that optimum hydrophobicity and size of the substituents were necessary for high activity.

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1-(2-Benzyl-3, 3-dimethylbutanoyl)imidazoles and related compounds were prepared and tested for their fungicidal activity against powdery mildew on barley (Erysiphe graminis) and gray mold on cucumber (Botrytis cinerea) by pot tests. The benzyl group at the 2-position of 1-(3, 3-dimethylbutanoyl)imidazoles was necessary for high activity against both fungi. Substitution at the 2- or 3-position of the benzene ring of 1-(2-benzyl-3, 3-dimethylbutanoyl)imidazoles was unfavorable to the activity. The activity of ten 1-(2-benzyl-3, 3-dimethylbutanoyl)imidazoles with various substituents at the 4-position of the benzene ring against both fungi was shown by a regression analysis to be correlated with the electronic property of the 4-substituents, in which the stronger the electron-withdrawing power, the higher the activity. The activity of 1-acyltriazoles was lower than that of 1-acylimidazoles, especially against B. cinerea. The (+)-isomer of 1-[2-(4-substituted benzyl)-3, 3-dimethylbutanoyl]imidazoles was superior to the (-)-isomer in controlling both fungi.

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The effect of oryzalexin D, which has been isolated as a group of novel phytoalexins of rice plant, on DNA, RNA, protein, lipid and chitin biosyntheses, respiration and cell membrane permeability was investigated in Pyricularia oryzae. The concentration for 50% inhibition (ED₅₀) by oryzalexin D of the mycelial growth of P. oryzae was 230 ppm. At this concentration, oryzalexin D inhibited equally the incorporation of [2-¹⁴C]thymidine, [2-¹⁴C]uridine, L-[U-¹⁴C]amino acid mixture, L-[methyl-¹⁴C]methionine and D-[1-¹⁴C]glucosamine into DNA, RNA, protein, lipid and chitin in intact cells, but did not inhibit these systems in a homogenate of the mycelia of P. oryzae. Oryzalexin D scarcely inhibited the respiration of the homogenate and mitochondria at ED₅₀. On the other hand, oryzalexin D at ED₅₀ caused leakage of potassium and inhibited the uptake of glutamate by mycelial cells of P. oryzae. These results suggest that interference with the cell membrane function is responsible for the primary mode of action of oryzalexin D against P. oryzae.

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The Sharpless asymmetric epoxidation was used for the synthesis of both D-erythro-dihydrosphingosine triacetate and (2S, 3S, 5R)-2-acetamino-5, 9-dimethyl-8-decene-1, 3-diol. A ¹³C-NMR study of the latter coupled with biogenetic considerations enabled us to propose (2R^*, 3R^*, 5R^*, 13S^*, 14R^*)-relative stereochemistry for natural aplidiasphingosine. (2R, 3R, 5R, 13R, 14R)-(+)-aplidiasphingosine was synthesised starting from (R)-(+)-citronellic acid.

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An alkalophilic Bacillus No. KX-6 isolated from soil produced a D-xylose isomerase in alkaline media. The striking characteristic of this bacterium was its especially good growth in alkaline media. The D-xylose isomerase of this bacterium was purified by ammonium sulfate fractionation, DEAE-Sepharose ion exchange column chromatography and G-200 gel filteration. The molecular weight and sedimentation constant were approximately 120, 000 and 9.35S, respectively. The enzyme was most active at pH 7-10 and was stable at pH 6.0 to 11.0. Enzyme activity was stimulated by cobalt ion but inhibited by Hg²⁺, Ag²⁺, and Cu²⁺. Substrate specificity studies showed that this enzyme was active on D-xylose, D-glucose, D-ribose, and D-arabinose. The smaller Km value and larger V_max value for D-xylose indicated that this enzyme is essentially D-xylose isomerase.

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