During an organ culture of lactating bovine mammary explants in the presence of lactogenic hormones, the radioactivity from D-[1-¹⁴C]mannose (Man) and N-acetyl-D-[1-¹⁴C]glucosamine (GlcNAc) was incorporated rapidly into the lipid-saccharide (C/M), lipid-oligosaccharide (C/M/W) and protein fractions, which were endogenous acceptors in the N-linked glycoprotein fromation. The distribution of radioactivity in the C/M, C/M/W and protein fractions at 6 hr incubation was 5, 2 and 93% for [¹⁴C]GlcNAc, but 34, 1 and 65% for [¹⁴C]Man, respectively. The labelled sugars in the C/M and C/M/W fractions were identified to be Man and GlcNAc. Man in the C/M fraction was mannosyl phosphoryl dolichol, and both Man and GlcNAc in the C/M/W fraction were incorporated into lipid-linked oligosaccharide, which was composed of trisaccharide through dodecasaccharide. Polyacrylamide gel electrophoretic analysis of the protein fraction indicated that six polypeptides were labelled. Of the major peaks, one was caseins and the other was glycoproteins corresponding to the glycoproteins of the plasma membrane. The results suggest that the molecular size of lipid-linked oligosaccharide and the acceptor proteins differed from those of the bovine mammary membranes and rabbit mammary explants.

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To study whether the phosphoserine residue is associated with the antigenicity of bovine α_s1-casein, we examined the antigenic reactivity of dephosphorylated α_s1-casein, peptide 1-25 from bovine β-casein and three chemical reagents with IgG antibody specific to native α_s1-casein by an enzyme-linked immunosorbent assay.
The reaction between native α_s1-casein and its IgG antibody was inhibited more strongly by native α_s1-casein than by dephosphorylated α_s1-casein. Peptide 1-25, having a phosphoserine residue-concentrated region from bovine β-casein, noticeably inhibited the reaction between native α_s1-casein and its antibody. Furthermore, the O-phospho-L-serine residue inhibited the reaction of peptide 61-123 with anti-native α_s1-casein antibody, although L-serine and sodium phosphate showed no measurable inhibition.
These results suggest that the phosphoserine residue associated with part of an antigenic site in bovine α_s1-casein.

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(+)-Phomalactone, (+)-acetylphomalactone, (+)-asperlin and their isomers were synthesized from 3-triethylsiloxypropyne and (S, E)-1-formyl-2-butenyl benzoate, which was easily prepared from (2R, 3S, E)-1, 2-cyclohexylidenedioxy-4-hexene-3-ol.

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Mutants of Saccharomyces cerevisiae that produce sufficient isoamyl acetate were isolated from sake yeast. 5, 5, 5-Trifluoro-DL-leucine, an analogue of L-leucine, was used for the isolation to eliminate the feedback inhibition by accumulated L-leucine. The concentration of isoamyl alcohol increased about three or four times with these mutants and a sufficient concentration of isoamyl acetate, one of the key components of the sake flavor, was obtained consequently. Mutants producing sufficient isoamyl acetate were also isolated from wine, shochu and beer yeasts by the same method.

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Defatted-dried rice flour and untreated rice flour were extruded with a twin-screw extruder, and the characteristics of the extrudates were compared with each other. The defatting and drying treatment was effective for improving the expansion ratio and the degree of gelatinization of the rice-flour extrudate. Microscopic observation showed that the extrudate of the defatted-dried flour had a large number of minute cavities, while that of the untreated flour had a small number of larger cavities. Before extrusion-cooking, both the specific surface area and the micropore volume of the defatted-dried rice flour particles were larger than those of the untreated rice flour particles. After extrusion-cooking, both the specific surface area and the micropore volume of the defatted-dried flour extrudate were smaller than those of the untreated flour extrudate.

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A rapid and simple assay procedure of high-molecular-weight polysaccharides is required for the activity measurement of polysaccharide-synthesizing or -hydrolyzing enzymes. When an aqueous solution of dextran was assayed fluorospectrometrically at a fixed wavelength of 340 nm for both excitation and emission, a strong response based on Rayleigh's light scattering was observed. There was a linear correlation between the spectral intensity and concentration of the native dextran, and the intensity was proportional to the molecular weight of the dextran. Two model experiments verified the applicability of fluorospectrometric analysis. That is, a kinetic measurement of dextran synthesis by this method corresponded well with the results evaluated by the reducing end group analysis. Differences between endo-type and exo-type dextranases were clearly demonstrated. Moreover, the endodextranase action on the dextran could be followed by the changes in spectral intensity of the incubation mixture placed in the cuvette. Although fluorospectrometric analysis is applicable to polysaccharides other than dextran, its use is restricted to homogeneous substrates or enzymes. High-performance liquid chromatography with a gelfiltration column indicated that the spectral intensity was specific for the high-molecular-weight dextran, while a differential refractometer gave responses to all sugars including those with low-molecular-weights.

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Six strains of actinomycetes (strains A, C, E, F, I, and J) isolated from the water and sediments in Lake Kasumigaura were found to produce musty odorous compounds. These strains were identified as Streptomyces species by their morphological and physiological characteristics. Musty odor substances were isolated from the isolate culture broth and identified as 2-methylisoborneol and geosmin by GC/MS analysis. Four strains (A, C, E, and I) of the isolates produced both geosmin and 2-methylisoborneol, while the other 2 strains (F and J) produced only 2-methylisoborneol.
The courses of 2-methylisoborneol and geosmin production were observed using strains A and I on BS medium. The maximum amounts of 2-methylisoborneol and geosmin for strain A were 156μg/l and 56μg/l, and for strain I they were 32μg/l and 20μg/l.
Physical and chemical factors influencing the musty odor production were studied using strains A and I. The optimum temperature and pH for the odor production of both strains were 25°C and pH 9.0. Moreover, the amounts of nutrients such as nitrogen, phosphorus, magnesium, iron, and starch favorable for the musty odor production were investigated.

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Excellent L-glutamine producers were screened for among sulfaguanidine resistant mutants derived from the wild type L-glutamic acid-producing bacteria, Brevibacterium flavum, Brevibacterium lactofermentum, Corynebacterium glutamicum and Microbacterium ammoniaphilum.
The best strain, No. 1-60, was a sulfaguanidine resistant mutant derived from B. flavum 2247 by mutation. Strain No. 1-60 accumulated 41.0mg/ml of L-glutamine after 48 hr of cultivation from 10% glucose as a carbon source. This yield was the highest among those so far reported.
The addition of Mn²⁺ (2ppm) to the standard medium for B. flavum 2241 decreased the L-glutamine production and increased the L-glutamic acid excretion markedly. On the contrary, strain 1-60 was not affected the Mn²⁺ (2ppm) addition at all.
Glutamate kinase activity and the intracellular content of ATP in sulfaguanidine resistant mutant No. 1-60 were higher than those in the parent strain, B. flavum 2247.
It was confirmed that the increase in glutamate kinase and the increase in internal ATP, which were important for the L-glutamine synthesis, were very effective for the improvement of L-glutamine-producing mutants.

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Excellent L-phenylalanine producers were screened from among tyrosine, methionine doubly auxotrophic and antimetabolite resistant mutants derived from a L-glutamic acid-producing bacterium; Brevibacterium lactofermentum 2256.
A selected mutant, Brevibacterium lactofermentum No. 123, produced 21.7mg/ml of L-phenylalanine in 72 hr when 13% glucose was supplied as a carbon source. The accumulation of L-phenylalanine by strain No. 123 became 5.17-fold higher than that by parental strain No. 808.
This yield was the highest among those so far reported.
The addition of fumaric acid to the culture medium promoted the L-phenylalanine production.
Accumulation of other amino acids in the culture broth was negligible compared with that of the main product, L-phenylalanine.

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We previously reported that Gly-Gly-Arg-Pro and Arg-Pro-Gly-Gly, the derivatives of a bitter peptide Arg-Pro, had no bitterness although Gly-Arg-Pro and Arg-Pro-Gly had a bitter taste at the same level as that of Arg-Pro. To elucidate the mechanism of elimination of bitterness by the introduction of the Gly-Gly residues, we synthesized Gly-Gly derivatives of other bitter peptides such as Phe-Phe, Val-Val-Val, and Arg-Pro-Phe-Phe, and examined the effectiveness of Gly-Gly residues in eliminating bitterness. We suggest that, for Arg-Pro and Val-Val-Val, the Gly-Gly residue might prevent a hydrophobic group from binding to a taste receptor.

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Candida catenulata CBS 1904, the previous type strain of C. ravautii, was selected as the best strain for the production of threo-D_s-isocitric acid from water-insoluble carbon sources, noncarbohydrates. The addition of surfactants, lipophilic polyoxyethylene nonyl phenyl ethers, was essential for the acid production, because the cell surface of the strain was less lipophilic. n-Alkanes, ranging from C₁₁ to C₁₄, gave the acid in high yields. The acid was produced in a jar fermentor in an about 90% yield on a weight basis as to n-tetradecane supplied. The acid was easily recovered, as crystals of its monopotassium salt, from the concentrated culture broth filtrate.

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Microbial reduction of (±)-2, 4-dimethylcyclohex-2-en-1-one by Beauveria sulfurescens led mainly to two isomers of 2, 4-dimethylcyclohexanols. By oxidation of these alcohols, chiral building blocks for cycloheximide synthesis were obtained, namely (-)-(2R, 4R)-2, 4-dimethylcyclohexan-1-one and (-)-(2R, 4S)-2, 4-dimethylcyclohexan-1-one.

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Mitogenic substances on human peripheral blood mononuclear leukocytes were screened from culture filtrates of microorganisms newly isolated from soil and sea water by measuring [³H]-thymidine incorporation into the cells. Strong mitogenic activity was found in marine bacteria, particularly in marine vibrios. These mitogen samples exhibited neither hemagglutinating activity nor leukoagglutinating activity. They could scarcely stimulate murine lymphocytes.
Cell-cell interaction among leukocyte subsets in response to a bacterial mitogen was investigated using the most powerfully mitogenic sample (culture filtrate of strain H 52-2). A slight decrease in the mitogen response was observed on depletion of plastic surface adherent cells. Separation of T and non-T cells from each other by erythrocyte-rosette sedimentation resulted in a markedly diminished mitogen response. Considerable restoration of the mitogen response was obtained when T cells were mixed with mitomycin C-treated adherent cells or mitomycin C-treated non-T lymphocytes, or when non-T lymphocytes were mixed with mitomycin C-treated T cells.

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Paraquat inhibited the acetylcholinesterase activity of human erythrocytes and electric organs of Electrophorus electricus. The inhibition of acetylcholinesterase activity was reversible, as shown from the following two experimental results: [I] The degree of inhibition was not affected by changing the preincubation time of the enzyme and paraquat before the addition of the substrate. [II] The enzyme, preincubated with paraquat and subsequently freed from inhibitor by gel filtration on Sephadex G-25, showed the same activity as the untreated enzyme. Paraquat gave effective protection against the inhibition by an irreversible anionic site inhibitor, dibenamine, but not by irreversible esteratic site inhibitors, dichlorvos and methanesulfonyl chloride. These results indicate that paraquat functions as a reversible inhibitor for the anionic site. The inhibitory powers and Hill coefficients of paraquat and diquat were compared with the other quaternary ammonium compounds. Although secondary to edrophonium, paraquat strongly inhibited acetylcholinesterases of human erythrocytes and electric eel, and showed higher inhibition selectivity for both acetylcholinesterases than for human plasma butyrylcholinesterase. The Hill coefficients concerning the interaction of paraquat with acetylcholinesterases of human erythrocytes and electric eel were given as 0.83 and 0.73, respectively. This indicates negative cooperativity between these enzymes and paraquat, which is similar to the case with d-tubocurarine. On the other hand, diquat showed weak inhibitory power and low inhibition selectivity, and its Hill coefficients were almost 1.0, indicating a competitive inhibition mode.

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Glycinin was dialyzed against low ionic strength buffer (μ=0.01) and centrifuged in sucrose density gradient. Two major components with the sizes of 7S and 11S were obtained. When each component was separately recentrifuged, the intrinsic peak of each was predominantly given. This indicates that there were two molecular species in the glycinin, one being dissociable and the other undissociable at low ionic strength. The dissociable species reversibly associated to the size of 1 IS at high ionic strength. The conformation of each species was different, the dissociable species being more random and unstable than the undissociable species at low ionic strength. The dissociable species contained more ASIV and less ASIII than the undissociable species.

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For thermostable lipase production by Humicola lanuginosa No. 3, a simple optimized medium consisting of (%, w/v): sorbitol, 1.0; corn steep liquor, 1.0; NaCl, 0.5; CaCl₂•2H₂O, 0.01; Silicone Km-70 (antifoamer), 0.2; and whale oil or castor oil as a lipase inducer, 0.3, was used. The yield of the lipase was about 80-120U/ml after 25 hr aerobic cultivation at 45°C when the pH was maintained at 7 to 8. The acetone powder preparation of the enzyme was most active at pH 7.0 and 45°C. The enzyme retained 100% activity on incubation for 20 hr at 60°C. The enzyme was able to hydrolyze almost all forms of natural fats tested (14 kinds), coconut oil being the most rapidly hydrolyzed.

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The hydrolysis and esterification by a thermostable lipase from Humicola lanuginosa No. 3 were investigated. Both reactions occurred readily at temperatures between 45-50°C. Esterification by the enzyme with glycerol was observed to be specific towards fatty acids with carbon numbers of C12-C18. Laurie acid esters with different alcohols such as primary alcohols, terpene alcohols, etc., were also synthesized readily. Esterification by the enzyme was adversely affected by the water content (optimum, ca. 7%), however, the hydrolysis rate increased rapidly with increasing water content (optimum, ca. 60%). The enzyme showed increased activity in organic solvent-aqueous reaction systems. Nevertheless, hydrolysis in complete organic phase reactions was found not to be feasible. Hydrolysis at a higher temperature (50 or 55°C) in a solvent free phase was almost the same as that in organic solvent-aqueous phase reactions. The components of glycerides varied considerably during hydrolysis, whereby esterification resulted in a higher quantity of mono-and diglycerides (about 40%), compared to in the case of hydrolysis, for which the value was about 10-20%.

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All four Stereoisomers of pyriculol were synthesized to assist in forming a correlation between their chemical structure and biological activity. The (R, E)-2-hydroxy-3-pentenal derivative was coupled with a lithium acetylide derivative to give a diastereomeric mixture of the acetylenic alcohol, which led to the antipode of pyriculol and its 3'-epimer. Similarly obtained were the natural pyriculol and its 3'-epimer from the (S)-isomer of this aldehyde.

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In the course of screening for anti-platelet principles produced by micro-organisms, strong anti-platelet activity was detected in the culture broth of Aspergillus fumigatus Fres. The purified active compound was identified as gliotoxin. Gliotoxin inhibited ADP-induced aggregation as well as collagen- or arachidonate-induced aggregation of rabbit platelets (IC₅₀ = about 27 μM) and also accelerated the dissociation of aggregates. Gliotoxin also inhibited the heat hemolysis of rabbit erythrocytes, suggesting that this agent is a membrane-stabilizing anti-aggregant. The disulfide structure in the gliotoxin molecule was responsible for the inhibitory activity, because desthiogliotoxin had effects on neither platelet aggregation nor heat hemolysis of erythrocytes.

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Microscopic and dynamic mechanical properties for mixed aqueous gels of agar and gelatin have been studied. The microscopic observation showed formation of micro granules in the gels under the phase-contrast visual field. The constituent was recognized as agar by metachromatic staining using a microspectrophotometer. Dynamic moduli of the gels were measured from 0.01 to 200 Hz by phase difference and by resonance. A minimum E' value was obtained for the mixed gel at a volume fraction of agar of 0.6. E' of all gels and E" of mixed gels were frequency dependent above 30 Hz.

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Mutants exhibiting high catalase activity were derived from Candida boidinii S2 strain AOU-1, from among mutants resistant to H₂O₂, NaN₃ or 3-amino-1, 2, 4-triazole (ATA). The catalase activity of an ATA-resistant strain was improved by means of a methanol-limited chemostat culture with H₂O₂ supplementation. The catalase activity increased with increasing H₂O₂ concentration in the feed medium in the range where methanol did not remain. Alcohol oxidase activity increased after adaptation of the cells to H₂O₂. Cells of mutant strain SA051 grown under the optimal culture conditions produced 1200 mM formaldehyde in the reaction mixture.

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During differentiation after auxin withdrawal, the change in the ethylene production of Hiproly barley callus paralleled the change in 1-aminocyclopropane-1-carboxylic acid (ACC) content. The levels of ACC and ethylene production decreased rapidly, and then increased in Hiproly barley callus.
Aminooxyacetic acid (AOA) prevented the ACC and ethylene production of the callus. Moreover, aminoisobutyric acid (AIB) also inhibited the ethylene production, but did not prevent the ACC synthesis of the callus. On the other hand, methylglyoxal-bis(guanylhydrazone) (MGBG) greatly enhanced the ACC and ethylene production. Formation of adventitious roots in Hiproly barley callus was enhanced by the cultivation in the medium containing AIB or AOA. However, differentiation of the callus was strongly inhibited by MGBG.
Thus, prevention of ethylene production may be significant for differentiation of Hiproly barley callus.

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Sex pheromone components of the female Crocidolomia binotalis, an insect pest of cabbages in Indonesia, were identified from the ovipositor tip extract of virgin females by analyzing with chromatographic fractionation and capillary GC/MS. In an EAG response and attractivity test with a wind tunnel system, a mixture of synthetic compounds, (Z)-9-tetradecenyl acetate (Z-9-TDA) and (Z)-11-hexadecenyl acetate (Z-11-HDA), in the ratio of 1:7-1:60 and an amount of 1-50 ng on a filter paper, showed strong activities comparable to the activity of the ovipositor tip extract, which contained the two compounds at a ratio of c. 1:10 (Z-9-TDA:Z-11-HDA). The mixture of these two compounds might be the sex pheromone of C. binotalis.

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A protein exhibiting only enoyl-CoA hydratase (EC 4.2.1.17) activity was purified from an n-alkane-grown yeast, Candida tropicalis. This enzyme had a homotetrameric form composed of subunits with a molecular mass of 36kDa. On the other hand, a bifunctional enzyme exhibiting enoyl-CoA hydratase and 3-hydroxyacyl-CoA dehydrogenase (EC 1.1.1.35) activities was obtained from the same yeast cells when purified in the presence of protease inhibitors, phenylmethylsulfonyl fluoride, antipain and chymostatin. The enzyme had a molecular mass of 105 kDa and was a monomeric form. Limited proteolysis of the bifunctional enzyme with α-chymotrypsin yielded a peptide mixture containing a 36 kDa fragment, the mixture showing about 76% of the original enoyl-CoA hydratase activity but no 3-hydroxyacyl-CoA dehydrogenase activity. Comparison of the peptide maps of the purified enoyl-CoA hydratase and the 36 kDa fragment obtained from the bifunctional enzyme showed the similarity of these proteins. These results strongly suggest that the domain of enoyl-CoA hydratase is separable from the bifunctional enzyme through the action of a certain protease.

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To investigate the substrate specificity of β-L-rhamnosidase, the following β-L-rhamnopyranosides were synthesized: 1-(β-L-rhamnopyranosyl)-DL-glycerol (1), methyl β-L-rhamnopyranoside (2), methyl 2-O-(β-L-rhamnopyranosyl)-β-D-glucopyranoside (3) and methyl 2-O-(β-L-rhamnopyranosyl)-α-L-arabinopyranoside (4). The synthesis of 3 was performed using L-quinovose with neighboring group participation, which lead stereoselectively to the β-L-quinovoside. The 2-OH of the L-quinovo-unit was selectively deblocked, oxidized to the keto group, and then stereoselectively reduced, whereby 3 was produced.

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Acylated anthocyanins in the Commelinaceae were distinguished from other substances by high-performance liquid chromatography (HPLC) with concurrent three-dimensional photodiodearray detection (250-700nm), and four new acylated anthocyanins were isolated by preparative HPLC.
According to the fast atom bombardment mass spectral (FABMS) analysis, alkalinehydrolysis and the absorbance ratio between λ_max of around 320 nm and that around 500 nm, the new pigments were characterized as follows: zebrinin [MW (as flavylium ion) 1553, caffeic acid × 4] from Zebrina pendula', monodecaffeylzebrinin [MW 1391, caffeic acid × 3] from Zebrina pendula; rhoeonin [MW 1433, ferulic acid × 3] from Rhoeo spathacea; and setcreasin [MW 1609, ferulic acid × 4] from Setcreasea purpurea.

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Lactobacillus casei ATCC 7469 was successfully converted to protoplasts by treatment with endo-N-acetyl muramidase in sucrose phosphate buffer. For full hydrolysis of cell walls, a high concentration of sucrose and a cold shock were necessary. Mg²⁺ ions enhanced the stability of protoplasting cells. The cell wall regeneration of protoplasts was more effective on gelatin-induced regeneration medium than with the soft overlay method. The optimal concentration of gelatin was 2.5%. The frequency of regeneration was found to be about 6% for the protoplast prepared by enzyme treatment for 20min. The mutants having streptomycin resistance and rifampicin resistance, as selection markers for the detection of fusion, were isolated by UV irradiation and NTG treatment. These mutants were stable for at least several transfers. Protoplast fusion was carried out using PEG (50% solution of polyethyleneglycol, M.W. 6, 000). The frequency of protoplast fusion was found to be about 10^-5.

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An obligate Chemolithoautotroph, Thiobacillus ferrooxidans AP19-3, could utilize amino acids, other than glycine, methionine and phenylalanine, as a sole source of nitrogen. However, both the growth rate and growth yield were lower than those in Fe²⁺-NH₄⁺-salts medium, suggesting that the ammonium ion was a superior nitrogen source for the strain compared to amino acids. Methionine and phenylalanine strongly inhibited the cell growth on Fe²⁺-NH₄⁺-salts medium at 10 mM. [¹⁴C]Glycine could not be taken up into the cells, and this meant the strain could not use glycine as a sole source of nitrogen. The uptake of [¹⁴C]leucine into the cells was dependent on the presence of Fe²⁺. When the strain was cultured on Fe²⁺ - leucine (10 mM)-salts medium lacking an inorganic nitrogen source for 5 days at 30°C, 83.5% and 16.5% of the cellular carbon were derived from carbon dioxide and leucine, respectively, indicating that carbon dioxide was a superior carbon source for the bacterium compared to leucine. The ammonium ion did not inhibit the utilization of leucine for cellular carbon. Leucine uptake was markedly inhibited by inhibitors of protein synthesis, such as chloramphenicol (94.3% at 1 mM), streptomycin (57.2% at 5mM) and rifampin (77.2% at 0.1 mM), respectively. Carbon dioxide uptake was also completely inhibited by chloramphenicol at 4 mM. These results suggest that the transport of both amino acids and carbon dioxide into the cells was dependent on protein synthesis.

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A new antibiotic was obtained from the cultured broth of an actinomycete identified as Streptomyces capoamus, and has been named capoamycin. The structure of capoamycin was elucidated by NMR spectral analysis and chemical degradation, which revealed that capoamycin was composed of a modified benz[a]anthraquinone chromophore, a β-C-olivoside and (E, E)-2, 4-decadienoic acid. Capoamycin inhibited the growth of Gram-positive bacteria, yeasts and fungi, induced differentiation of mouse myeloid leukemia cells (Ml) and prolonged the survival periods of mice bearing Ehrlich ascites carcinoma.

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The determination of lower fatty acids is important in environmental and biological studies. In particular, volatile fatty acids with four up to six carbon atoms are strongly malodorous and their odor threshold values are fairly low. Therefore, determination of trace amounts of these acids is necessary. Many investigations on the gas chromatographic (GC) determination of lower fatty acids have already been reported.^1-6) But the methods used are not sufficient for sensitive and selective analysis.
The average detection limits for lower fatty acids on GC using a capillary column have been of nanogram level. Therefore, derivatization of these acids is very necessary for trace analysis because of the sharpness of peaks. However, methylation or trimethylsilylation of lower fatty acids is not so effective because of the high volatility of the products and the lack of diagnostic ions for selected ion monitoring (SIM). In order to overcome these problems, Burke and Halpern⁷⁾ recently performed the butylation of lower fatty acids for mass spectrometry (MS). But the detection limits for five C₄-C₅ acids with their method were 30.4 to 52.1nM.
In this study, lower fatty acids were converted to benzyl esters with benzyl alcohol and the esters formed were analyzed by SIM using a capillary column. The detection limits were around sub-picogram level and the selectivity was very high.

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A facultative anaerobic xylan-using alkalophile has been isolated from an alkalophilic compost fermented for the screening. The strain was gram-positive in the very early stages of growth, and is a sporeforming rod. The strain having anteiso-, iso-branched, and straight-chain cellular fatty acids, lacked cytochrome, quinone, and catalase. It was a facultative anaerobe, whose μ_max of aerobic and anaerobic culture were 0.70 h^-1 and 0.82 h^-1, respectively. Xylanase activity was higher in anaerobic culture than aerobic culture. In static culture, after sharp consumption of oxygen in the medium, xylanase production started. The main fernjentation products from xylan in anaerobic or static culture were formic acid, ethanol, acetic acid, and pyruvic acid, and were acetic and pyruvic acids in aerobic culture.
The strain has new characteristics of production of metabolites and xylanase, and has new intermediate characteristics between the genera Bacillus and Clostridium.

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A new cyclitol derivative, streptol (1), was isolated from a culture filtrate of an unidentified Streptomyces sp., and the structure of 1 was determined as 1D-(1, 2, 4/3)-5-hydroxymethyl-5-cyclohexene-1, 2, 3, 4-tetrol. This structure was elucidated with NMR and MS spectrometry, and the absolute configuration was determined from the CD spectrum of the tetrabenzoate of the hydrogenolized compound of 1. Streptol inhibited the root growth of lettuce seedlings at a concentration above 13ppm.

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Methyl muconate of arylglycerol was identified as a novel product of aromatic ring cleavage of a β-O-4 lignin substructure model dimer by lignin peroxidase of Phanerochaete chrysosporium. The muconate is an immediate aromatic ring cleavage product of the β-O-4 dimer.

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