Three mature wethers fitted with rumen fistulas were used to investigate the effects on nitrogen kinetics of sodium propionate and sodium acetate added to their diet. The wethers were fed at 12 equal intervals daily in sequence on (1) crushed lucern hay cubes (basal diet) with sodium propionate, (2) basal diet only and (3) basal diet with sodium acetate. Supplemented energy as sodium propionate and sodium acetate were both 5.1% of gross energy in the basal diet. The isotope dilution method, with a single injection of [¹⁵N] urea into blood and [¹⁵N] ammonium chloride into the rumen, was used to determine the metabolic rates of nitrogen in plasma urea and ruminal ammonia. When wethers were fed the diet with sodium propionate, the concentration and irreversible loss rate of ruminal ammonia significantly decreased relative to when they were fed the basal diet. The production rate of ruminal ammonia from dietary and endogeneous sources, except for urea, and nitrogen transfer rates from ruminal ammonia to plasma urea also decreased. The effect of supplementing sodium acetate to the diet on these kinetics of ruminal ammonia was smaller than that of sodium propionate. The concentration of plasma urea and urinary urea excretion significantly decreased when wethers were fed the diet with both VFA salts, though no clear change was observed in the transfer rate of plasma urea N into the digestive tract. The nitrogen excretion in urine was significantly reduced by the supplementation of both VFA salts, but nitrogen retention tended to increase only when wethers were fed the diet with sodium propionate. It is concluded that the supplementation of sodium propionate at the level used in this experiment decreased urinary urea excretion but did not affect urea recycling via the rumen. The smaller response of nitrogen kinetics to sodium acetate compared with sodium propionate would be associated with sodium acetate's weaker effect on ruminal ammonia production.

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Sheep were fed a diet (2.0% body weight of alfalfa hay cube and 0.5% body weight of mixed concentrate) either with or without salinomycin supplementation (20mg/day) for 2 weeks in order to clarify the effect of dietary salinomycin on postprandial changes in plasma insulin and glucagon concentrations, insulin secretory response to glucose and tissue responsiveness to insulin (insulin action). Insulin secretory response to glucose and tissue responsiveness to insulin were measured by the hyperglycemic clamp and the hyperinsulinemic euglycemic clamp techniques, respectively. In the experiment of the response to feeding, plasma insulin and glucagon concentrations and the molar concentration ratio of insulin and glucagon increased (P <0.05) after the initiation of feeding in both treatments. Their response areas tended to be smaller for the diet with salinomycin than for the diet without salinomycin. The ratio of plasma insulin increments to glucose infusion rate in the hyperglycemic clamp experiment and the glucose infusion rate in the hyperinsulinemic euglycemic clamp experiment did not differ between the dietary treatments. It is suggested in sheep that the dietary salinomycin supplementation for 2 weeks gives no significant effects on postprandial plasma insulin and glucagon concentrations, and insulin secretory response and action.

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Hinai-dori, (Hinai-dori×Rhode Island Red), one of the Japanese native chickens, had been appreciated to be palatable and delicious for traditional local dishes. In order to confirm whether Hinai-dori meat is actually tasteful as widely accepted and to identify the taste components of Hinai-dori, sensory evaluation and chemical analysis of Hinai-dori meat were conducted. First, the palatability of Hinai-dori meat was compared with that of broilers by sensory evaluation. Hinai-dori meat was judged to be more palatable. Therefore, out of possible taste components, free amino acids and 5'-inosinic acid (IMP) in meat extracts from 3 strains, Hinai-dori, broilers and layer pullets, were chosen for analyses. No significant differences were detected in glutamic acid and other amino acids among 3 strains. However, the IMP content in Hinai-dori meat, 3.25μmol/g, was 50% and 60% higher than that in broiler and layer pullet meat, respectvely. Finally, simplified chemical solutions of IMP and/or glutamic acid were employed for sensory evaluation. The solutions simulated to Hinai-dori extracts had more palatability than those of broiler extracts. These results indicate that preference of Hinai-dori to broilers could be accounted for in part by the difference of composition of IMP together with glutamic acid.

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Laying Japanese quail were given diets containing varying levels of betacyclodextrin (0, 10 and 20%) ad libitum for 4 weeks. Body weight decreased with increasing dietary beta-cyclodextrin levels, though feed intake was hardly affected by the dietary treatment. Hen-day egg production rate was rapidly decreased with the dietary beta-cyclodextrin levels in a dose dependent fashion. Egg yolk cholesterol concentration was significantly higher in the 10% dextrin group than in the control group and which may be reflected by decreased egg production rate in the 10% dextrin group.

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The specific and rapid fractionation of glycopeptides containing N-acetyl-neuraminic acids (NANA) and/or ester sulfates (-SO₄) was performed by affinity chromatography using a column immobilized egg white lysozyme (Lz) as a ligand. The two model samples used were as follows: caseinoglycopeptide (CGP, κ-Cn: f106-169), which was prepared from bovine κ-casein (non-sulfated sialoglycoprotein) by chymosin digestion, and ovomucin glycopeptide (OGP), which was obtained from hen ovomucin (OM, sulfated sialoglycoprotein) by actinase E digestion. Stepwise elution with NaCl (0 -0.5M) was superior for mutual separation of the sample components. When CGP was applied on the column, asialo-CGP was eluted in the non-adsorbed fraction and the effective separation of pure sialyl-CGP (eluted with 0.1M NaCl) was attained. OGP was separated into a neutral (non-adsorbed) and two acidic (eluted with 0.1-0.3M NaCl) glycopeptide fractions. In particular, the acidic fractions were completely separated into glycopeptides binding NANA (0.1-0.2M NaCl) and co-binding NANA Plus -SO4 (0.3M NaCl) at the biological pH range of around 7.0 without the cleavage of labile NANA bonds. Moreover, under the condition of 0.2M NaCl, sulfated sialoglycopeptides could only be directly isolated from protease digested whole egg white without through the preparation step of OM.

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β-Galactosidase was highly purified from the cytosol of Lactobacillus acidophilus JCM 1229 to homogeneity about 490-fold with 1.3% recovery by salting-out, ion-exchange, hydrophobic, affinity, and hydroxyapatite chromatographies. The molecular weight of the native enzyme was estimated to be 290kDa by gel permeation HPLC. The optimum pH was found to be 5.5 and the stable pH range was 5.5-6.5. The optimum temperature was found to be 50°C.The Km values for o-nitrophenyl-β-D-galactopyranoside (ONPG) and lactose as substrates were 0.59mM and 5.13mM, respectively. Both a reductant (2-mercaptoethanol) and metal ions (Mn²⁺ and Mg²⁺)strongly activated β-galactosidase activity.

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Proteinases contained in 4 types of cheese imported from Denmark and Germany (Samsoe and Maribo cheese from Denmark and Tilsit and Trapist cheese from Germany) were separated by using CM-Sephadex. As a result, 3 proteinases were eluted from each cheese sample at salt concentrations of 0.3, 0.6, and 0.8-0.9M. Regarding each proteinase, the optimum pH, effects of various reagents and action on casein were examined. Consequently, proteinases eluted at the same salt concentration showed the same properties. Thus they were refferred to as the same enzyme. The proteinase eluted at 0.3M showed the maximum activity at pH 3.8 to 4.0 and was completely inactivated with pepstatin. It quickly decomposedκ-casein to thereby give a para κ-casein-like decomposition product. The proteinase eluted at 0.6M showed the maximum activity at pH 4.0 and was completely inactivated by pepstatin. It quickly decomposed κ-casein to thereby give a substance being the same asαs1-I casein, β-I and para κ-casein in mobility.The properties of these enzymes suggest that they are milk coagulating enzymes employed at the early stage of cheese making. The properties of the latter enzyme are identical with those of chymosin which is a milk coagulating enzyme. The proteinase eluted at 0.8-0.9M had the optimum pH of around 8.0 and was strongly inhibited by soybean trypsin inhibitor and diisopropyl fluorophosphate. It formed a γ-casein-like decomposition product. These properties agree with those of milk alkaline proteinase.

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The kinetics of thermal denaturation of porcine hemoglobin (Hb) at pH 7.2 was investigated in order to elucidate the difference in thermal stability of the heme protein derivatives. The denaturation of oxyhemoglobin (O₂Hb), reduced hemoglobin (RHb) and methemoglobin (MHb) were compared. Hb was denatured above 60°C.The denaturation was faster in the order, RHb, O2Hb and MHb. In particular RHb was very stable to heat. The half-life times of MHb, O2Hb and RHb at 70°C, calculated from thermal denaturation rate constant k, were 22 sec, 2min and 161 min, respectively. The denaturation of RHb was slow in the presence of sodium hydrosulfite (Na₂S₂O₄) as reductant, but the denaturation of MHb was independent of the concentration of potassium ferricyanide (K3Fe(CN)₆) as oxidant. The relationship between denaturation rate of Hb derivatives and temperature obeyed the Arrhenius plot. Activation energy of Hb derivatives were 80-85kcal/mol. However, RHb had a transition temperature at 77°C, with the energy being 151.1 kcal/mol above this temperature. It is suggested that MHb is denatured directly, while O2Hb and RHb are denatured via MHb. Freezing or freeze-drying sample is considered not to be desirable for the examination of biochemical aspects, since this treatment decreased the thermal stability. These results might relate to the color changes that occur in cooked meat.

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A total of 47 strains of lactic acid bacteria were isolated from 14 kinds of yogurts and 15 kinds
of starter cultures for commercial use. Twenty-eight strains were identified as Lactobacillus
species, which were composed of 18 strains of Lactobacillus delbrueckii subsp. bulgaricus, 5 strains
of L. helveticus, 2 strains of L. acidophilus, 2 strains of L. casei and 1 strain of L. delbrueckii subsp.
lactis. The remaining 19 strains were Streptococcus salivarius subsp. thermophilus.. These strains
of Lactobacillus and Streptococcus species were tested for mutual inhibitory activity. Sixteen
strains of S.salivarius subsp. thermophilus inhibited the growth of Lactobacillus species. Among
Lactobacillus species, a broad inhibitory spectrum was shown in some strains of L. helveticus, L.
acidophilus, L. casei and L. delbrueckii subsp. lactis. Particularly, L. delbrueckii subsp. lactis 5001
inhibited all strains of lactobacilli examined. Inhibitory effect of MRS broth culture filtrates
from L. delbrueckii subsp. lactis 5001 seemed to be due to both hydrogen peroxide and low
molecular weight antimicrobial substance (_??_1, 000Da).This antagonistic compound was insensi-
tive to 7 kinds of protease and amylase, and stable at heat (12•C, 15min) and pH(2-10).

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