Chemometric methods were applied for analyzing the relationship between the classification of coffee cultivars and their volatile components. Six typical cultivars were selected from Coffea arabica L., and their headspace profiles were analyzed by GC and GC/MS. A canonical discriminant analysis, with GC peaks as the variables, suggested the existence of a relationship between the sensory characteristics and canonical variables. The six coffee cultivars were divided into three groups, respectively having a roasted note, sweet aroma and fermented odor. It is suggested that Brazil and Mandheling varieties had a roasted note derived from methylpyrazine, while Mocha coffee had a fermented odor derived from 2, 3-butanedione.

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Shredded cabbage (Brassica oleracea L., Capitata group) was stored under a dynamically controlled atmosphere (DCA) and modified atmosphere (MA) at 5°C. Quality factors were measured every 2 days. Browning was suppressed as the CO₂ concentration was increased (0% to 15%), with no influence from O₂ concentration (2. 5% to 10%). The development of an off-odor was markedly delayed with an increase in O₂ concentration, such an odor being detected after 6 days at 2. 5% O₂, 8 to 10 days at 5% to 7. 5% O₂, and not at all above 10 days at 10% O₂, while the off-odor development was little affected by CO₂ concentration (5% to 15%). Total sugar, polyphenolics, total ascorbate, and total microbial count were little influenced by O₂ and CO₂. These results show that shredded cabbage can be kept in good condition with a combined high O₂ and high CO₂ atmosphere. These findings are largely different from those for MA storage.

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Sulfated N-myristoyl chitosan (S-M-chitosan), which is strongly electrolytic and water soluble as well as partly hydrophobic due to long alkyl chains, was synthesized to be used as a liposome-surface modifier. The effects of the treatment with an aqueous S-M-chitosan solution on the stability of the liposome suspension prepared from hydrogenated egg yolk lecithin were examined on several points. A suspension of large liposomes prepared by the Bangham method was precipitated by standing for a day, but the precipitation was restrained when the sample was treated with S-M-chitosan solution. The turbidity of a small liposome suspension Was changed greatly after the suspension was freeze-thawed, but the change was small in the treated sample. A similar result was obtained when the suspension was freeze-dried following the addition of water. These results come from the facts that the surface of the liposome was coated with S-M-chitosan and negatively charged as ascertained by the measurement of zeta potential and the electron microscopic observation. The repulsive force between charges was considered to be the origin of the stabilization. It was also shown from an ESR experiment that the treatment suppressed the elution rate of the material incorporated into the liposomes.

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D-Glucosaminate (D-GlcNA) dehydratase from Pseudomonas fluorescens was inhibited stoichiometrically by metal-chelating agents (EDTA, 8-hydroxyquinoline-5-sulfonic acid, α, α'-dipyridyl and o-phenan-throline). The activity of EDTA-treated enzyme was restored by incubation with Mn²⁺ (0.4 mM) or Ca²⁺(2 mM) in the presence of pyridoxal 5'-phosphate (PLP, 0.2 mM) in veronal buffer (VB, 40 mM, pH 8) at 37°C for 30 min. The atomic absorption spectrum of the native enzyme showed that the enzyme contained 1 mol of Mn²⁺ per mole of enzyme. Although the EDTA-treated enzyme was unstable at 4°C, addition of Mn²⁺ and PLP to the solution of the EDTA-treated enzyme prevented the inactivation. The K_m of the restored enzyme for D-GlcNA was somewhat lower than that of the original enzyme. However, the K_m for PLP increased 14-fold. These results suggest that D-GlcNA dehydratase contains Mn²⁺ near the PLP-binding site, and the metal ion appears to stabilize the structure of the active site.

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Pyruvate dehydrogenase multienzyme complex was purified from Bacillus caldolyticus. The complex was composed of four polypeptides with molecular masses of 39.8, 41.7, 53.7, and 57.5kDa estimated by SDS-PAGE and they were presumed to be pyruvate decarboxylase (E1, dimeric), lipoate acetyltransferase (E2), and lipoamide dehydrogenase (E3) on the analogy of those from Bacillus stearothermophilus. E1 and E3 were stable at pH 5.7-10.2 and 4.5-11.3, respectively. Halves of E1 and E3 activity were abolished by incubation for 30 min at 65°C and 85°C, respectively. Loss of overall activity was principally due to inactivation of E1. Structural changes in the complex incubated at high temperature were studied by fluorescence spectroscopy. The results suggested that the thermal denaturation of the complex proceeded through at least two different steps : inactivations of E1 and E3, and the former process is accompanied by a reduction of the complex size.

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Chymotrypsin inhibitors were purified from larval hemolymph of Bombyx mori. The purification steps involved ammonium sulfate fractionation (30-70%) and liquid chromatography on Butyl-Toyopearl 650M, Sephadex G-75, concanavalin A-Sepharose, Mono-Q, and Mono-S columns. Fourteen isoforms of chymotrypsin inhibitor were resolved in hybrid crosses : ten isoforms from c60 × n511, eight from k03 × FJ1, and nine from i10 × p50. Chromatographic and electrophoretic studies on the inhibitors suggested that they were expressed co-dominantly and could be classified into three molecular-size groups : 8-13 kDa, 40 kDa, and 42kDa. CI-b4, CI-13a, CI-13b, and CI-13c in the first group, CI-3 in the second group, and CI-8 in the third group were present in all of the hybrids. Inhibitors in the third size group had an affinity for concanavalin A-Sepharose. It was found that CI-13 was composed of three different inhibitors.

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Coaxial dual-cylinder apparatus was used to measure the effective thermal conductivity of aqueous solutions of glucose, sucrose, gelatin and egg albumin over a temperature range from -20° to 20°C by the steady state method. The accuracy of the apparatus was confirmed by testing with water and ice. The effective thermal conductivity decreased with an increase in the total solid content in both the frozen and unfrozen states. In the unfrozen state, the effective thermal conductivity was slightly dependent on temperature. In the frozen state, however, the effective thermal conductivity was strongly dependent on temperature; lower temperatures gave higher effective thermal conductivity, reflecting the increase in the ice fration. For the unfrozen samples, the intrinsic thermal conductivity of each solid component was calculated by heat transfer models. All the models tested, series, parallel and Maxwell-Eucken, were equally applicable to describe the heat conduction in the unfrozen state. In the frozen state, however, the strong temperature dependency of the effective thermal conductivity suggests that the effect of the temperature dependency of the ice fraction should be incorporated into theoretical models.

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The neutralization titer of anti-human rotavirus (HRV) IgY was completely inactivated by pepsin at pH 2.0. However, it was not significantly affected by trypsin or chymotrypsin under certain conditions. The immunological activity of the IgY was observed in the intestine of suckling mice for 2h after oral administration and the activity rapidly decreased thereafter. The effects of oral supply of IgY were thus estimated for HRV-induced diarrhea in suckling mice and it was found that a previous supply of the IgY (1h before HRV infection) completely prevented the HRV-induced diarrhea. The preventive effect was decreased as the time gap between IgY administration and HRV infection was longer. However, the oral supply of the IgY within 24h after HRV infection was still effective and decreased the incidence of HRV diarrhea in suckling mice.

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A nitrate-reducing bacterium was isolated from a hot spring and identified as Bacillus licheniformis. This strain was found to accumulate NO^-₂ in the medium even in the presence of NH⁺₄ by shaking culture when FeSO₄ was added to the medium. The NO^-₂ accumulation was due to nitrate reductase activity, and the same accumulation was also recognized in some other bacteria. Since the nitrate reduction had no marked effect on the cell growth, it is possible that this nitrate reduction may not be involved in either an assimilatory or a dissimilatory one like those hitherto reported.

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The effects of NaCl and heating temperature on the gel-forming ability of legumin were studied. The addition of NaCl progressively increased the denaturation temperature of legumin. Heating to around the denaturation point, i.e., below the onset temperature (zone 1), between the onset and maximal temperatures (zone 2), between the maximal and final temperatures (zone 3), and above the final temperature (zone 4), affected both the gel-forming ability and gel properties. No gel was formed in zone 1, while the gel was harder in zone 3 than in zones 2 and 4. The gel hardness gradually decreased with increasing temperature in zone 4. Differences in the viscoelastic and microstructural properties between gels heated at various temperatures around the denaturation point were observed.

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Xanthomonas campestris INXC-1 is able to freeze water at a subzero temperature higher than -5°C. High-pressure treatment at 300 MPa and 5°C for 5 min killed the cells without affecting their ice-nucleation activity. Egg white containing the pressurized cells began to freeze with a slight degree of supercooling. Ice crystals with a dendritic structure were formed when the egg white froze in the presence of the killed bacterial cells. The frozen egg white thawed more quickly than egg white frozen without the cells.

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We have cloned a genomic DNA sequence encoding the acid protease (PEPA) from Aspergillus oryzae using a 0.6-kb fragment as a probe. This fragment was amplified by the polymerase chain reaction (PCR)using oligonucleotide primers designed from the partial amino acid sequences of peptide fragments of the purified protein. Nucleotide sequencing analysis has shown that the cloned gene (designated pepA) encodes 404 amino acid residues and contains 3 putative introns ranging in length from 50 to 61 nucleotides. The deduced amino acid sequence of the A. oryzae PEPA has a high degree of homology (67%) to the A. awamori PEPA. Comparison with the amino acid sequence of A. awamori PEPA suggests that the A. oryzae PEPA may consist of a 78 amino acid prepro-peptide and 326 amino acid mature protein. The amino acid composition of the mature protein was almost consistent with that of the acid protease purified from A. oryzae reported previosuly. Southern hybridization analyses showed that the pepA gene exists as a single copy in the A. oryzae chromosome. The cloned gene was found to be functional, since transformants of A. oryzae containing multiple copies of the pepA gene showed a 2-6 fold increase in acid protease activity compared with the recipient strain.

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Flower fragrance compounds were found to be produced from the precursor solution obtained from flower buds by crude enzyme prepared from the flowers at the opening stage. GC and GC-MS analyses showed the formation of volatile aroma constituents from the precursor solution of Jasminum polyanthum F, Jasminum sambac Ait, and Gardenia jasminoides E, but none in the case of Osmanthus fragrans L. The aroma-producing enzyme activity of G. jasminoides rapidly increased to reach the maximum at flower opening stage (stage 4) and decreased within 24h after flower opening (stage 5). Fragrance precursors of G. jasminoides were suggested not to be mainly β-glucosides of linalool, eugenol, borneol, and isoeugenol based on the results after β-glucosidase and naringinase treatment of the precursor solution. The activity of hydrolytic enzyme(s) such as glycosidase was found to elevate during flower opening to result in the aroma formation.

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The inhibitory activity of an angiotensin I-converting enzyme (ACE) detected in soy sauce was fractionated into two major fractions of high molecular weight (Hw) and low molecular weight (Lw) by gel filtration chromatography on Bio-gel P-2 after treating with ethanol. The Hw fraction reduced the blood pressure in hypertensive rats after orally administering, while the Lw fraction did not. The ACE inhibitor in the Hw fraction was further purified by Dowex 50W ion-exchange chromatography and four subsequent steps of HPLC. On the basis of the SIMS-mass spectrum, NMR spectrum and other characteristics, the purified ACE inhibitor was identified as nicotianamine (N-[N-(3-amino-3-carboxypropyl)-3-amino-3-carboxypropyl]azetidine-2-carboxylic acid). The IC₅₀ value for this ACE was 0.26μM.

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The substrate specificity and the affinity of rat purified lecithin-cholesterol acyltransferase towards the molecular species of phosphatidylcholine (PC) were studied in comparison with the human enzyme. The substrate vesicles were prepared with 40% of a test PC, 60% of egg yolk PC, and tritium cholesterol. Both human and rat enzymes showed similar high reactivity to the substrates containing three major PCs (16 : 0-18 : 1 PC, 16 : 0-18 : 2 PC, and 18 : 0-18 : 1 PC) of egg yolk compared with the vesicles of egg yolk PC alone. In the case of 18 : 0-20 : 4 PC, the rat enzyme had the highest activity among all the test PCs, but the human enzyme only had a moderate activity. Even when the substrate consisted of 18 : 0-20 : 4 PC alone, the rat enzyme had a high activity, but the activity of the human enzyme was not detected. Symmetrical diacyl-PCs (18 : 2-18 : 2 PC, 18 : 1-18 : 1 PC, 18 : 0-18 : 0 PC) were not a preferable substrate for either enzyme. The transfer of both the human and rat enzymes from the vesicles containing 18 : 0-20 : 4 PC to the egg yolk PC vesicles was on a higher level than that from the vesicles containing 18 : 2-18 : 2 PC. This suggests that the activity of the LCAT can be easily influenced by the kinds of PC molecular species and its relative content in the substrate and that the substrate may provide the extent of the enzyme transfer between the substrate particles.

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A calcium chelating fluorescence indicator, fura-2, was used to measure intracellular ionized calcium in Caenorhabditis elegans. The indicator loading process was harmless to the nematode, and completed within 2-3 h. Fura-2 was loaded mainly at its intestinal tract. The effects of DOPA on locomotion and the level of intracellular calcium were investigated and measured by using a microfluorometer. The addition of DOPA temporarily increased [Ca²⁺]_i for several minutes.

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A glycinin-digesting protease was purified from 4-h-imbibed soybean seeds to apparent homogeneity by a combination of DEAE-cellulose, gel filtration and Shodex IEC QA-824 chromatography. The purified soybean protease showed a single band on SDS-PAGE and degraded the carboxymethylated glycinin molecule at neutral or alkaline pH. The glycinin-digesting protease has an apparent molecular mass of 98 kilodaltons as estimated by SDS-PAGE under both reduced and non-reduced conditions. A peptidic substrate for the soybean protease was detected and purified from a tryptic digest of glycinin A₅A₄B₃ complex ; it corresponded to Ala(375)-Lys(381) of the B₃ subunit. It was found that the protease could hydrolyze the peptide bond between Tyr(378) and Asn(389) of that peptide. The soybean protease was significantly inhibited by PMSF, indicating the endopeptidase is a serine protease. Moreover, the glycinin-digesting activity is also susceptible to EDTA and the inactivated enzyme could be restored by the addition of MnCl₂, suggesting that Mn²⁺ is an important factor for the endopeptidase activity. To our knowledge, this is the first report of purification and characterization of a glycinin-digesting protease from soybean seeds.

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Poly(α-L-guluronate)lyase, which depolymerizes polyguluronate of alginate, was purified from the culture medium of a marine bacterium isolated from the intestine contents of a red sea bream, Pagrus major. The enzyme was homogeneous as judged by polyacrylamide gel electrophoresis in the presence and absence of SDS and the molecular weight of 42, 000 and 40, 000 on SDS gel electrophoresis and on a Sephacryl S200HR column chromatography, respectively. The activity of the enzyme was higher at around pH 8.5 and stable from pH 6-10. The active form of the enzyme, which has been thought to be once lost upon incubation of the enzyme at higher temperatures up to 80°C could be restored on cooling the enzyme. The residual activity was 45% even at 100°C. By treatment with other denaturants, the activity was maintained in 3% SDS and was 70% in 6M GHCl and 60% in 4M urea on incubation at 25°C for 30 min. In addition, several chemical reagents were tested for the relationship between the functional amino acid residue and the active form of the enzyme.

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Geranylgeranyl diphosphate (GGPP) synthase [EC 2.5.1.29] was purified to homogeneity from Methanobacterium thermoformicicum SF-4. The enzyme was a dimeric protein consisting of two identical subunits (M_r=39, 000) and catalyzed prenyl transfer reactions using isopentenyl diphosphate (K_m=30.8μM)and either dimethylallyl diphosphate (K_m=16.8μM), geranyl diphosphate (K_m=12.6μM), or farnesyl diphosphate (K_m=14.7μM) as allylic partners. During a sequential elongation, C₅→C₁₀→C₁₅→C₂₀, intermediates were accumulated with various ratios to the final product GGPP. In the presence of 0.8M KCl, GGPP synthease activity was greatly enhanced, stabilized to heat treatment at 65°C for 30min, and protected from inhibition by p-chloromercuribenzoic acid. No other prenyltransferase synthesizing C₂₀ or shorter prenyl diphosphate was observed in M. thermoformicicum SF-4. These suggest that GGPP synthease alone is important in the biosynthetic pathways to squalene and membrane polar lipids at a chain elongation stage in this strain.

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The induction of NADPH-generating enzymes by polychlorinated biphenyls (PCB) in rats was investigated. The administration of PCB to rats for 3 and 14 days increased the activities of malic enzyme (ME, EC 1.1.1.40), glucose-6-phosphate dehydrogenase (G6PD, EC 1.1.1.49), and 6-phosphogluconate dehydrogenase (6PGD, EC 1.1.1.44) about 2-fold above the control level in the liver. Hepatic mRNA levels of ME, G6PD, and 6PGD, except for G6PD mRNA of the 14-day group, were also elevated to the same degree as the enzyme activities in PCB-treated rats. In rats fed a PCB-containing diet for 1 day, the hepatic mRNA levels of ME and G6PD were elevated prior to the induction of enzyme activity. In the kidney, lung, spleen, heart, and testis, the mRNA levels of ME, G6PD, and 6PGD were not affected by PCB. The induction of hepatic NADPH-generating enzymes would imply an increased demand of NADPH in the liver of rats fed with a PCB-containing diet.

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Syntheses of optically pure turmeronol A and turmerone were achieved in a simple manner starting from ethyl (R)-3-hydroxybutanoate (4) of 100% e. e. The key step was the displacement of the chiral tosylate (6) with an organocopper reagent.

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The complete amino acid sequence of momordin-a, a ribosome-inactivating protein from the seeds of bitter gourd, has been analyzed. Twenty-two peptides were isolated from the tryptic digest of momordin-a and sequenced by the DABITC/PITC double coupling method. The alignment of these tryptic peptides was done by analyzing the amino acid sequences of the peptides derived from chymotryptic digestion and cyanogen bromide cleavage of momordin-a as well as V8 protease-digestion of the CNBr fragment. Momordin-a consisted of 250 amino acid residues and carbohydrate residues attached to Asn227, and its molecular mass was calculated to be 28, 690Da. The sequence comparison with ricin A-chain shows that 33% of the residues of momordin-a are identical to those of ricin A-chain and that the residues involved in the catalytic site of the ricin A-chain are conserved in momordin-a.

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Alcaligenes xylosoxydans subsp. xylosoxydans A-6 (Alcaligenes A-6) produced N-acyl-D-aspartate amidohydrolase (D-AAase) in the presence of N-acetyl-D-aspartate as an inducer. The enzyme was purified to homogeneity. The enzyme had a molecular mass of 56 kDa and was shown by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) to be a monomer. The isoelectric point was 4.8. The enzyme had maximal activity at pH 7.5 to 8.0 and 50°C, and was stable at pH 8.0 and up to 45°C. N-Formyl (K_m=12.5mM), N-acetyl (K_m=2.52mM), N-propionyl (K_m=0.194mM), N-butyryl (K_m=0.033mM), and N-glycyl (K_m=1.11mM) derivatives of D-aspartate were hydrolyzed, but N-carbobenzoyl-D-aspartate, N-acetyl-L-aspartate, and N-acetyl-D-glutamate were not substrates. The enzyme was inhibited by both divalent cations (Hg²⁺, Ni²⁺, Cu²⁺) and thiol reagents (N-ethylmaleimide, iodoacetic acid, dithiothreitol, and p-chloromercuribenzoic acid). The N-terminal amino acid sequence and amino acid composition were analyzed.

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The best inducers for D-aminoacylase from Alcaligenes xylosoxydans subsp. xylosoxydans A-6(Alcaligenes A-6) were a poor substrate, N-acetyl-γ-methyl-D-leucine, and an inhibitor, N-acetyl-D-alloisoleucine. The enzyme has been homogeneously purified. The molecular weight of the native enzyme was estimated to be 58, 000 by gel filtration. A subunit molecular weight of 52, 000 was measured by SDS-PAGE, indicating that the native protein is a monomer. The isoelectric point was 5.2. The enzyme was specific to the D-isomer and hydrolyzed N-acetyl derivatives of D-leucine, D-phenylalanine, D-norleucine, D-methionine, and D-valine, and also N-formyl, N-butyryl, and N-propionyl derivatives of D-leucine. The K_m for N-acetyl-D-leucine was 9.8 mM. The optimum pH and temperature were 7.0 and 50°C, respectively. The stabilities of pH and temperature were 8.1 and 40°C. D-Aminoacylases from three species of the genus Alcaligenes differ in inducer and substrate specificities, but are similar with respect to molecular weight and N-terminal amino acid sequence.

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The monitor peptide receptor in the small intestine was investigated. The receptor is on the intestinal mucosal cells [Biochem. J., in press]. The specific binding of the ¹²⁵I labeled monitor peptide to dispersed rat small intestinal cells was inhibited by treatment with p-toluensulfonyl-L-lysine chloromethyl ketone (TLCK), an affinity labeling reagent for trypsin. Soybean trypsin inhibitor (SBTI) did not inhibit the binding. Analysis with reduced SDS electrophoresis-autoradiography indicated that an affinity-cross-linked complex of the ¹²⁵I labeled monitor peptide and the receptor was abolished by the TLCK treatment but was not affected by the presence of SBTI. Histochemical studies found a predominatnt binding of ¹²⁵I labeled monitor peptide on cholecystokinin (CCK)-immunoreactive cells in tissue sections of the rat upper intestine. The result suggests that the monitor peptide receptor is on the surface of CCK-producing cells.

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Methyl (±)-11-(2-hydroxyethyl)thio-6, 11-dihydrodibenz[b, e]oxepin-2-carboxylate (5) was enantioselectively acylated with acetic anhydride in an organic medium by Lipase Amano P to give methyl (-)-11-(2-acetoxyethyl)thio-6, 11-dihydrodibenz[b, e]oxepin-2-carboxylate (8), and the (+)-enantiomer by Lipase Sigma Type VII. Using Lipase Amano P, (+)- and (-)-(5) could be prepared with high optical purity (84-94% e.e.). These products were respectively converted to (+)- and (-)-KW-4099, which had antiallergic activity with complete retention of the optical purity.

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α-L-Arabinofuranosidase was purified from a cell-free extract of Aspergillus niger 5-16 by chromatographies on DEAE-Toyopearl, SP-Toyopearl, Ultro-gel AcA 44, Mono P, and TSK-GelG3000SW. The final preparation thus obtained showed a single band on SDS-polyacrylamide gel electrophoresis. The molecular weight and isoelectric point were 67, 000 by SDS-polyacrylamide gel electrophoresis and pH 3.5by isoelectric focusing. The α-L-arabinofuranosidase contained amino acids in the order of Asx>Gly>Ala>Thr>Glx=Ser. The enzyme had maximum activity at pH 4.0 and 60°C, and was stable from pH 4 to 7 and at temperatures up to 30°C. The enzyme activity was not affected considerably by either metal ions or chemical reagents. The enzyme released arabinose from p-nitrophenyl-α-L-arabinofuranoside, O-α-L-arabinofuranosyl-(1→3)-O-β-D-xylopyranosyl-(1→4)-D-xylopyranose, and arabinan, but not from O-β-D-xylopyranosyl-(1→4)-O-[α-L-arabinofuranosyl-(1→3)]-O-β-D-xylopyranosyl-(1→4)-D-xylopyranose, O-β-D-xylopyranosyl-(1→2)-O-α-L-arabinofuranosyl-(1→3)-O-β-D-xylopyranosyl-(1→4)-O-β-D-xylopyranosyl-(1→4)-D-xylopyranose, gum arabic, or arabinoxylan. The limit of hydrolysis of arabinan was about 58% even when the enzyme was sufficiently in excess.

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Cellular responses to intracellular accumulation of UDP-galactose (UDP-Gal) were investigated for D-galactose-induced lysis of an Escherichia coli galE mutant. The mutant, ara-207, showed dramatic lysis in a nutrient broth supplemented with D-galactose after 3h of cultivation when transformation of normal rod cells into bulged- and spheroplast-like cells was clearly observed under electron microscope. UDP-Gal had been already detected with the optimal level at 2h of cultivation, followed by a drastic decrease in its level as well as a significant increase in the level of active (inhibitor-free) UDP-sugar hydrolase (USH)together with the bacterial lysis. Significant loss of UTP, UDP, and UDP-N-acetylglucosamine agreed with the in vivo activity of USH thus produced. Addition of D-sorbitol did not restrict UDP-Gal accumulation but did mostly protect ara-207 against the above morphological changes of the cells in which overproduction of USH was repressed over 3 to 4h of cultivation. These results suggested that accumulation of UDP-Gal could have some growth inhibitory effect on E. coli cells but the compound was not directly involved with the following lytic process via spheroplast formation. A possibility was taken into account, that the accumulation of UDP-Gal caused overproduction of USH, which may provoke inhibition of bacterial peptidoglycan synthesis.

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We isolated 18 cDNA candidates that were expected to encode parts of the self-incompatibility-associated RNase of Lycopersicon peruvianum PI 126441 (S_11a-plant) from a style cDNA library. Polymerase chain reaction was used with oligonucleotides derived from conserved amino acid sequences of RNases from fungi and S-associated RNases in other species of Solanaceae. Two of these clones (both do not have full length sequences) gave 826-bp and 730-bp sequences, and they had the same open reading frame, named ORF-1. Comparison of the deduced amino acid sequence of ORF-1 with S-associated RNase of other Solanaceous plants showed a high degree of similarity. mRNA encoding this ORF-1 was about 1000 bases long and detected only in the style tissue by Northern analysis. Using one of the cDNA clones as a probe, we detected sequence variability among three different S-genotypes of randomly chosen wild-type tomatoes by Southern analysis. From these results, it was concluded that ORF-1 encodes the self-incompatibility associated S-glycoprotein of L. peruvianum PI 126441 (S_11a-plant).

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Okara Tempe (OT), an Indonesian fermented traditional food, which is the fermented okara (insoluble residues of homogenized soybean, OC) by Rhizopus oligosporus, and which is interested in as a new high fiber and low energy soybean foodstuff. In this study, the effects of protein and dietary fiber (DF) of OT on sterol metabolism in rats were investigated. When rats were fed by OT or casein as protein source, the cholesterol and bile acid levels in plasma was significantly lower in OT fed group than in casein fed group. When rats were fed by OT or OC as DF source, in OT fed group, the cholesterol and bile acid levels in plasma was similar to them in OC fed group, but the cholesterol level in liver was lower than it in OC fed group, and the excretion of cholesterol and bile acid in feces was larger than in OC fed group. These results suggest that the cholesterol lowering action of OT in plasma would arise from the complementary action of protein and water soluble DF in OT.

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High performance liquid chromatography (HPLC) analysis of the culture filtrate of an isolated mold, Aspergillus terreus S-4, showed a larger peak of a terrein-like substance than those of gallic acid and protocatechuic acid. The chemical structure of this substance was investigated and identified as terrein, 4, 5-dihydroxy-3-propenyl-2-cyclopenten-1-one. We also examined some culture conditions for the production of terrein using a sake cake medium for strain S-4.

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It was suggested that several trehalose-containing oligosaccharides are present in yeast extract. Among these oligosaccarides a trisaccharides was isolated and identified as β-D-Glcp-(1→6)-α-D- Glcp-(1⟷ 1)-α-D-Glcp.

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Novel antifungal substances, antafumicins A and B, were isolated from a culture of Aspergillus niger NH-401 and determined to be trans- and cis-4-(3-acetyl-2, 6-dihydroxyphenyl)-2-methoxy-4-butanolide, respectively, by spectroscopic and single crystal X-ray analyses.

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