The interaction between subtilisin (Sbt) and Streptomyces subtilisin inhibitor (SSI) was examined by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE). When a mixture of Sbt and SSI was incubated together and then mixed with SDS-PAGE sample buffer at room temperature, it had abnormal behavior on SDS-PAGE; a single band corresponding to the complex migrated only to the top of the gel. Sequence analysis of the band electroblotted from the gel showed two major N-terminal sequences corresponding to Sbt and SSI. When the same Sbt/SSI mixture was analyzed by reverse phase-high performance liquid chromatography, protein eluted in positions corresponding to the intact forms of Sbt and SSI. Thus, it was concluded that the Sbt/SSI complex is stable upon exposure to SDS and migrates abnormally as a complex during SDS-PAGE; the abnormal migration stems from the inherent resistance of Sbt to SDS.
The denaturation of the Sbt/SSI complex was examined by heating it at different temperatures, rapid cooling, and SDS-PAGE. The band corresponding to the complex gradually disappeared as the temperature of the complex was increased from 70°C to 85°C; from this, the transition temperature was about 78°C. This temperature is higher than the known transition temperature of the Sbt alone (60°C to 65°C), indicating stabilization of the Sbt by SSI. This transition was accompanied by the appearance of low molecular weight species, none of which corresponded to the intact sizes of Sbt or SSI, indicating that autolysis occurred following denaturation.

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The composition of "group B saponin" in soybean seed was analyzed by HPLC, and six kinds of "group B saponin, " named Ba, Bb, Bb', Be, Bd and Be according to elution order from HPLC, were detected. Of these saponins, Ba, Bb, Bb' and Be were identified with soyasaponin V, I, III and II, respectively. Bd and Be were novel saponins possessing soyasapogenol E as the aglycone and the same sugar chain as Ba and Bb, respectively. These saponins were very unstable in the isolated state and had a tendency to form Ba and Bb, respectively. From these results, Bd and Be are presumed to be the precursors of Ba and Bb in soybean seed.

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Isoamyl acetate, one of the major components of flavor in a Japanese brewing product, sake, contributes to the fruity flavor of sake. We cloned Saccharomyces cerevisiae genes that cause overproduction of isoamyl alcohol, the precursor of isoamyl acetate, by increased gene-dosage effect. Three plasmids, pScFlr1, pScFlr2, and pScFlr3, were obtained by selection from the yeast genomic DNA which, on a multicopy plasmid, confer a phenotype resistant to 5, 5, 5-trifluoro-DL-leucine, an analogue of leucine. The cloned DNA fragments in the three plasmids had different restriction maps. Transformed cells with each of the plasmids produced large amounts of both isoamyl alcohol and isoamyl acetate. The gene cloned in the plasmid pScFlr1 was identified as the LEU4 gene encoding α-isopropylmalate synthase.

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For producing peptides with definite characteristics from a casein hydrolysate treated consecutively with thermolysin and papain, the hydrolysate was separated through two chromatographic steps into four peptide groups with high or low contents of aromatic amino acids (AAA) and branched chain amino acids (BCAA). The hydrolysate was first separated into AAA-poor and -rich peptide groups (one-half and 3 to 4 times as high as the AAA content of the hydrolysate) by both a conventional batch chromatography with Sephadex G-15 and a continuous one, with the same resin, of a simulated moving-bed type. The AAA-poor peptide group was further separated into a BCAA-rich (about 1.5-fold) peptide group and another one with an increased content of hydrophilic amino acids by batch chromatography with Toyopearl HW-40S.

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A pectate lyase gene III (pel III) of Erwinia carotovora Er was cloned. The gene was expressed independently of a vector promoter in both E. carotovora Er and Escherichia coli. The pel III product was largely excreted in the culture medium of E. carotovora Er, while the product was only exported to the periplasmic space and was not excreted in the medium of E. coli. Nucleotide sequence analysis of pel III disclosed an open reading frame of 1, 122 bp encoding a protein of 374 amino acids. The deduced amino acid sequence contained the N-terminal 30 amino acid sequence from the purified pectate lyase III (PL III) indicating the presence of a 22-amino-acid signal peptide. A putative ribosome-binding site was found to be 9 bp upstream of the start codon. The location of pel III was about 5.6 kb downstream of pel I. The PL III showed 80% homology in the amino acid sequence with the PL I of E. carotovora Er.9)

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A cDNA for Aspergillus oryzae glucoamylase was cloned, using oligodeoxyribonucleotide probes derived from amino sequences of peptide fragments of the enzyme. The glucoamylase cDNA, when introduced into Saccharomyces cerevisiae, directed the secretion of active glucoamylase into the culture medium. The complete nucleotide sequence of the cDNA contained an open reading frame encoding 612 amino acid residues. Comparative studies with other fungal glucoamylases showed homologies of 67% with A. niger and 30% with Rhizopus or yzae of the deduced amino acid sequences. In the five conserved regions reported in other fungal glucoamylases, the levels of homologies between those regions of A. oryzae and A. niger enzymes were much higher (78-94%). A. oryzae glucoamylase contained no peptide region abundant in threonine and serine residue (TS-region), like that proposed to adsorb onto raw starch in A. awamori var. kawachii glucoamylase.

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Culture medium containing 200μM o-dinitrobenzene suppressed cell growth of Issatchenkia orientalis for about 24 hr and after a lag phase, the cells began to increase with concomitant metabolism of o-dinitrobenzene by glutathione conjugation. The resulting glutathione conjugate, S-(2-nitrophenyl)glutathione, was further enzymatically metabolized and released into the growth medium. The final metabolite was identified as S-(2-nitrophenyl)cysteine by comparison with the authentic compound on HPLC. In the presence of o-dinitrobenzene, intracellular glutathione was not detected in the early log phase, but it began to accumulate after o-dinitrobenzene was metabolized. S-(2-nitrophenyl)glutathione and S-(2-nitrophenyl)cysteine, both chemically synthesized, did not suppress cell growth. These results suggest that there is a glutathione-related detoxification system in the yeast I. orientalis.

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The enzymes which metabolize 2-oxoaldehyde compounds in a crude extract of chicken liver were examined using 3-deoxyglucosone (3-DG) and methylglyoxal (MG). NADH- and NADPH-dependent reductase activities were observed and the latter was more than the former.
NADPH-dependent 2-oxoaldehyde reductase was purified from chicken liver by ammonium sulfate fractionation, and DEAE-cellulose, CM-celluIose, hydroxylapatite, and Sephadex G-100 column chromatographies. The molecular weight of the enzyme was estimated to be 38, 000 and 32, 000 by SDS-PAGE and gel filtration, respectively. The optimum pH was 6.5-7.0 and this enzyme was stable at pH 7.0-8.0. The Km for 3-DG and MG were 3.75 mM and 1.52 mM, respectively. This enzyme had high activities towards 2-oxoaldehyde compounds, such as 3-DG, MG, and phenylglyoxal. This enzyme converted 3-deoxyglucosone (3-DG) to 3-deoxyfructose, and methylglyoxal (MG) to acetol.

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The moles of monolayer adsorption of defatted rice flour, wheat flour, and corn fiber, and of active carbon as a reference, were measured using argon, nitrogen, krypton, ethane, propane, and butane. The relation between the moles of monolayer adsorption and the cross-sectional area of adsorbent molecules was not as expected for the smooth surface, but showed a fractal surface structure. A fractal dimension, D^σ, was calculated from the logarithmic relation between the moles of monolayer adsorption and the cross-sectional area of adsorbent molecules. The values of D^σ were not equal in general to the values of another fractal dimension, D^σ, calculated in our preceding paper from the logarithmic relation between the specific surface area and the particle diameter.

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Pneumococcal E-amidase (36.5 kDa, inactive form of the amidase) incubated with choline aggregates to form a high molecular mass (> 500 kDa), active C-amidase upon the removal of choline by dialysis at neutral pH. When choline was removed at alkaline pH (pH 8-9), aggregation of the enzyme was severely inhibited. The non-aggregated enzyme obtained at alkaline pH easily aggregated in the absence of choline and was active when the pH was shifted to neutral (pH 7). Furthermore, the high molecular mass amidase formed at neutral pH was dissociated at pH 9 to a low molecular mass (about 36.5 kDa). The dissociated amidase also reaggregated and was active when it was simply exposed to neutral pH. Since the original E-amidase itself neither aggregated nor was active by such a pH shift, these amidases obtained after the removal of choline at alkaline pH were suggested to be the intermediate molecules of the choline-mediated conversion of inactive E-amidase to the active form.

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Streptomyces sp. No. 35, taxonomically closed to S. thermodiastaticm, was isolated from domestic soil. It showed δ-glucosidase activity only in the cells. The enzyme synthesis was induced by cellobiose. Repeated DEAE-Toyopearl chromatography of a sonic extract of the cells showed three activity peaks, F₁, F₂, and F₃, which were eluted in the relative amount of 50:50:1 in this order by an NaCl concentration gradient. The enzymes were purified to homogeneity. Molecular weights of F₁, F₂, and F₃ were 100, 000, 105, 000, and 130, 000 by gel filtration, and 52, 000, 50, 000, and 52, 000, respectively, by sodium dodecyl sulfate-polyacrylamide-gel electrophesis. F₁ and F₂ hydrolyzed PNP-δ-glucoside and cellobiose nearly at the same rate, while F₃ hydrolyzed the former slightly. F₁ and F₂ were inhibited by glucose, giving Kis of 56 and 40 mM, respectively. On the other hand, F₃ was activated twofold by 0.1 M glucose and inhibited 50% by 1 M glucose. Xylose also similarly activated F₃. All the enzymes had δ-galactosidase activities. The δ-galactosidase activity of F₃ was not activated by any compounds tested, but rather inhibited by glucose and D-arabinose.

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Rhodopseudomonas addophila M402 grown under aerobic-dark condition shows two bands of dye-linked aldehyde dehydrogenase activity by polyacrylamide gel electrophoresis. The slowermigrating band coincided with the dye-linked aromatic alcohol dehydrogenase that was active on aromatic and aliphatic alcohols and aldehydes. The faster-migrating band was a new dye-linked aldehyde dehydrogenase. The latter enzyme was purified 125-fold by ultracentrifugation and column chromatographies on DEAE-cellulose, Bio-Gel HTP, and Sepharose CL-6B. The enzyme has a relative molecular mass of 70, 000 daltons, and a subunit size of 35, 000 dalton indicates the dehydrogenase has a dimeric structure. The isoelectric point was pH 4.74. NAD⁺and NADP⁺ do not act as electron acceptors. The enzyme was active specifically on straight chain aldehydes (C3-C10) rather than on benzaldehyde and its substitutes. Aromatic and aliphatic alcohols were inert for this enzyme. The Michaelis constant (HIM) were 1.6, 0.6, 0.9, 3.6, 0.5, 0.3, 0.1, 0.9, 0.6, 0.3, and 0.1 for benzaldehyde, m-hydroxybenzaldehyde, m-anisaldehyde, vanillin, propionaldehyde, butyraldehyde, hexaldehyde, heptaldehyde, octaldehyde, nonaldehyde, and decaldehyde, respectively.

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Neuraminidase was purified from the culture filtrate of Micromonospora viridifaciens in 4 steps. After the last step the enzyme appeared to be homogeneous on polyacrylamide gel electrophoresis, and the enzyme was crystallized by the addition of ammonium sulfate. The enzyme did not require Ca²⁺ ions for the activity and was not inhibited by EDTA. The enzyme was active on various sialocompounds such as N-acetylneuraminosyl-lactose (Km = 2.1 mm) and colominic acid (Km = 0.3 HIM). The activity was strongly inhibited by a sulfhydryl reagent, p-chloromercuribenzoate, and by oxidizing reagents such as N-bromosuccinimide and iodine. Its catalytic properties were compared with those of various microbial neuraminidases. M. viridifaciens neuraminidase was similar in many respects to Clostridium perfringens enzyme.

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The lipid distribution and function in the thylakoid membranes from a thermophilic cyanobacterium, Mastigocladm laminosus, were investigated. The thylakoid membranes were treated with digitonin and separated on a DEAE-cellulose column into fractions enriched in photosystem I or II complex. Lipid analyses showed a specific distribution of anionic lipids among the fractions. A mild delipidation of the membranes with cholate indicates that monogalactosyl diacylglycerol (MGDG) and sulfoquinovosyl diacylglycerol (SQDG) are released rapidly, while the major parts of digalactosyl diacylglycerol (DGDG) and phosphatidylglycerol (PG) are tightly associated with membranes, suggesting a different distribution between the two groups of lipids. Measurements of fluorescence of delipidated and reconstituted thylakoids showed the contribution of lipids to energy transfer. MGDG enhanced all the original fluorescence of thylakoids, while acidic PG and SQDG stimulated fluorescence of photosystem I and antena chlorophyll-protein complexes. DGDG was less effective under the conditions tested.

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Methyl epijasmonate (1) was stereoselectively synthesized from 3-hydroxymethylcyclopentanone (7). The intramolecular alkylation of bromoketone (8) or (9) was the key step to exclusively afford thermodynamically more stable oxahydrindanone (10) or (11). Synthesis was achieved in a 6% overall yield in 12 steps from (7).

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Over 20 'hairy root' clones of Ajuga reptans var. atropurpurea (Labiatae) were obtained from transformation with Agrobacterium rhizogenes MAFF 03-01724. Growth, opine synthesis and production of phytoecdysteroids in the clones have been examined. Mikimopine, a specific opine synthesized in the tissue transformed with strain MAFF 03-01724, was detected in most of the clones, and four phytoecdysteroids, 20-hydroxyecdysone, norcyasterone B, cyasterone and isocyasterone, were detected in all of the clones.
It was found that the production of phytoecdysteroids was closely related to the growth of hairy roots, by monitoring the changes in the culture. One of the rapidly growing and well branching hairy root lines, Ar-4, was selected and used for fermenter experiments. On an air-lift type culture of Ar-4 for 45 days, the weight of the root tissue was increased by 230 times and the content of 20-hydroxyecdysone reached 0.12% on a dry weight basis. This content is 4 times higher than those of the original roots.

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Ovomucin-protein conjugates were prepared to develop a new kind of functional glycoprotein-protein conjugates. Soluble reduced ovomucin was self-associated by transglutaminase and the reactant had better foaming and emulsifying properties than untreated ovomucin. The conjugation of ovomucin with casein or soy protein was also attempted by transglutaminase. Ovomucin-11S globulin and ovomucin-α_s1-casein conjugates were formed by cross-Unking between ovomucin and US globulin or α_s1-casein. The molecular weight of these conjugates were larger than that of ovomucin self-associated with transglutaminase. Ovomucin-11S globulin conjugate showed marked increases in the foaming properties, because of the high molecular weight of the conjugate. On the other hand, ovomucin-α_s1-casein conjugate had significant increases in the emulsifying properties, probably due to the increase in the hydrophobic(α_s1-casein)-hydrophilic(ovomucin) balance.

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We have reported that the trypsinized product of glycinin acidic subunit A_1a(A_1a/Tr) modulates insulin action on fat decomposition in vitro [Minami et al., Agric. Biol. Chem., 54, 511 (1990)]. This study was undertaken to get additional information on the modulation of insulin action by A_la/Tr. A_1a/Tr shifted the insulin-response curve of isoproterenol-stimulated lipolysis in isolated rat adipocytes to a lower insulin concentration and increased the maximal response elicited by the hormone. However, A_1a/Tr had neither an effect on the ability of insulin to stimulate glucose transport nor on the insulin binding to its receptor. Thus, A_1a/Tr potentiated some level(s) of insulin actions in vitro. A characteristic feature was that A_1a/Tr suppressed degradation of insulin that was internalized in a receptor-mediated manner. This protective effect alone, however, could not explain the total effects of A_1a/Tr. A possible explanation is offered for the mechanism of A_1a/Tr action. Apart from the action of A_1a/Tr on insulin, our results indicate a dissociation of the effect of insulin on glucose transport from that on lipolysis.

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13-Hydroperoxides (ROOM) and 13-hydroxides (ROH) of both linoleic and linolenic acids rapidly increased after inoculating press-injured spots of rice leaves with Pyricularia oryzae. The highest concentrations of ROOH and ROH were reached within 24 hr after inoculating with P. oryzae. On the contrary, the production of momilactone A, a terpenoid rice phytoalexin, began 24 hr after inoculating with P. oryzae, while the momilactone A level peaked at 96 hr after the inoculation. The 13-hydroperoxides and 13-hydroxides of linoleic and linolenic acids can thus induce phytoalexins production. Quinacrine, an inhibitor of phospholipase A₂, and the lipoxygenase inhibitor, nordihydroguaiaretic acid (NDGA), inhibited not only the production of ROOH and ROH, but also any phytoalexin accumulation following invasion by P. oryzae. Chlorogenic acid, by inhibiting the peroxidase of rice plants, inhibited the production of ROH and the rice phytoalexins accompanying an accumulation of ROOH. These data suggest that the oxygenated fatty acids, especially the hydroxides of linoleic and linolenic acids, in blast-infected rice leaves possibly act as endogenous elicitors of phytoalexin production.

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From the leaves of Rosa mgosa Thunb., four novel carotanoids which can be chemically derived from rugosic acid A (2) were isolated and their structures elucidated by spectroscopic and chemical methods. These naturally occurring carotane sesquiterpenes are implicated in the biogenesis of the R. rugosa carotane peroxides.

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A glycerol sensor, in which glycerol dehydrogenase was immobilized on Amino-Cellulofine, was developed for the continuous determination of glycerol in wine. NADH produced by the enzyme reaction was monitored amperometrically with a platinum electrode. A sandwich method was used for sample injection as an effective mixing mode of NAD and sample. A typical calibration curve showed a slightly convex curve between response and glycerol concentration (0.1-2 HIM; 1.8 × 10^-8 -3.6× 10^-7mol). The relative standard deviation for ten measurements of 9×10^-8 mol glycerol was 0.5%. The proposed method was used for wine analysis and was compared with an F-kit (enzymatic, spectrophotometric) method.

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To investigate the structure-activity relationships of host-specific HMT- and PM-toxins, 8 mimics of PM-toxin A, a component of the host-specific corn pathotoxin produced by Phyllosticta maydis, were synthesized as stereoisomeric mixtures. All the mimics, except for PM-7137, had four β-ketol groups spaced by tri- and tetra-methylenes, which is shorter than the penta-methylenes involved in native PM-toxins. A comparison of their biological activity clearly demonstrated the general structural features necessary for potent activity: four β-ketol groups were necessary with a spacing of chains equal to or longer than penta-methylene.

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In the presence of xanthine oxidase, 5-methyluridine was synthesized from inosine and thymine by the ribosyl transfer reaction using purine nucleoside phosphorylase and pyrimidine nucleoside phosphorylase. The hypoxanthine formed was converted into urate via xanthine by xanthine oxidase. After inosine was completely consumed, an equilibrium state, in which 5-methyluridine, thymine, ribose-1-phosphate, and phosphate were involved, was achieved. At the equilibrium state, maximum yield of 5-methyluridine was obtained. The equilibrium constant of the reaction (K= [thymine] [ribose1-phosphate]/[5-methyluridine][phosphate]) was 0.062. Based on the equilibrium constant, the yield of 5-methyluridine depended on a ratio of initial concentrations of inosine and phosphate, on condition that the initial concentrations of inosine and thymine were the same. The yields of 5-methyluridine in the presence and absence of xanthine oxidase were 76 and 33%, respectively, when the initial concentrations of inosine, thymine, and phosphate were 5 mM each.

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We have fused full length and the carboxyl-half of human MDR1 cDNA with the E. coli lacZ gene via a collagen linker and allowed their expression in yeast Saccharomyces cerevisiae. Using antibodies against β-galactosidase we partially purified the fusion proteins by immunoprecipitation and show here that the full length fusion protein has ATPase activity. By contrast, the fusion protein containing the carboxyl-half of P-glycoprotein did not show ATPase activity, indicating that both domains of P-glycoprotein are necessary. By treatment of the immunoprecipitated fusion protein with collagenase, P-glycoprotein was released from the β-galactosidase moiety. The results shown here open the possibility for a large scale purification of P-glycoprotein using this site specifically cleavable fusion protein.

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As a part of the study of bubble expansion in wheat flour dough under temperature rise, the critical radius for expansion, and the time course of expansion of an isolated bubble were investigated. As the required physical properties for the calculation of the critical bubble radius for expansion and the time course of bubble expansion, the authors measured the surface tension of the liquid phase of wheat flour batter as a function of concentration and temperature, and the apparent diffusion coefficients of air in wheat flour dough as a function of temperature. The critical radius for expansion and the time course of expansion of the isolated bubble under temperature rise were compared with the theoretical values calculated from the diffusion theory. At constant temperature, the time course of bubble shrinkage in wheat flour dough was described well by diffusion theory with the surface tension and the apparent diffusion coefficient, indicating that the bubble shrinkage would be rate-limited by the diffusion in the liquid phase of wheat flour dough of air out of the bubble. Under temperature rise from 3°C to 43°C, every bubble larger than the critical radius expanded. This result is physically admissible. On the other hand, the calculated time course of the bubble radius under temperature rise was not in agreement with the experimental data.

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We observed the presence of acid and neutral α-glucosidases with optimum pHs of 4.5 and 6.5, respectively, and their multiple forms in banana pulp. By chromatofocusing analysis, each α-glucosidase from preclimacteric bananas was found to be of pI > 7.4, which disappeared upon ripening, although another form with pI 5 as a major component appeared instead. It is unknown whether this phenomenon is due to protein de novo synthesis and/or post-translational modifications of the enzyme. A large amount of acid α-glucosidase from preclimacteric bananas was shown to be a glycoprotein that bound to a Con A-Sepharose column. While this type of enzyme decreased during ripening, it remained a possibility that sugar components of the enzyme might be processed during ripening. The neutral α-glucosidase had no affinity to the column through ripening. These results provide preliminary information on the mechanism of appearance of α-glucosidase multiforms as well as on a useful strategy for purification of acid and neutral α-glucosidases from banana pulp at various stages of ripening.

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Eleven strains of Aspergillus species isolated from Katsuobushi (dried bonito) were grown in a liquid medium containing 3-tert-butyl-4-hydroxyanisole (BHA), to examine the possibility of degradation of BHA by molding of Niboshi.
In the liquid medium, BHA was degraded by 11 strains of Aspergillus species. BHA in Niboshi was also degraded by the molding.

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The hydroxylation of 2-phenylpropionic acid (PPH) to 2-(p-hydroxyphenyl)propionic acid (HPPH) was investigated using various microorganisms. The highest hydroxylating activity was found in Streptomyces rimosus ATCC 10907. The reaction product was isolated and identified as 2-(p-hydroxyphenyl)propionic acid, which had no specific rotation, indicating that the reaction was not stereoselective at the benzylic position. In a 5-l jar fermentor containing a medium consisting of 2% sorbitol, 2% soybean meal, and 1% malt extract (pH 7.2), the conversion rate from 0.2% of PPH reached 60% using a PPH-resistant mutant, KY-661-18.

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Syntheses of 2α-, 3- and 4-deoxy and 3, 4-dideoxy derivatives of (+)-hydantocidin were accomplished by a single-electron-transfer reduction or by hydrogenation as the key step. The lack of herbicidal activity exhibited by these derivatives indicates the importance of the hydroxy groups on the furanose ring in (+)-hydantocidin.

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An ¹H and DSC study was done on the phase transition of a cetyl glucoside-water system. The system containing 23% water shows an exothermic peak at 45°C in the course of cooling due to the phase transition from liquid crystal to gel state. Above the transition temperature T_c, the NMR spectra consist of two peaks attributable to the water and the mobile alkyl chain. The latter disappeared when the temperature was lowered below T_c as the result of crystalization of the chains, and a weak peak emerged in the position between them. It was attributed to the water hydrated strongly on the glucosyl group in the inner part of the surface layer and not exchanging position with free water. After the temperature of the sample was kept at 3°C for four days, this signal disappeared, suggesting that the strongly hydrated water was expelled from the inner part and the surface structure was changed into a more riqid one. This change caused the elevation of T_c in the course of heating. The structures of the bilayer and the hydration are discussed and compared with those of phospholipids.

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A method was proposed to produce a peptide fraction from zein by enzymatic hydrolysis to improve the Fischer ratio, i.e., the molar ratio of the branched chain amino acids, leucine, isoleucine and valine, vs. the aromatic amino acids, phenylalanine and tyrosine. Zein was hydrolyzed first with alkalophilic proteinase and then with actinase to liberate aromatic amino acids. The hydrolysate, however, tasted bitter and it was modified with transglutaminase to decrease the bitterness. Sephadex G-15 adsorption chromatography was used on the debittered product to remove the aromatic amino acids liberated. A series of these enzymatic modifications and the chromatography afforded a final product with a Fischer ratio of 20.0 at a yield of 56% on a nitrogen basis. Such a very high Fischer ratio and a reasonable yield would warrant economic feasibility for producing this formula on an industrial scale.

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