Recently, it was suggested that lignan glycosides would exist in an oil cake of sesame seed. However, until now, the amount or composition of lignan glycosides were not reported exactly. We analyzed lignan glycosides in sesame seed by high-pressure liquid chromatography. A mixture of glycosides was extracted with aqueous methanol from the oil cake. The aglycons of each glycoside were identified by GC-MS and the number of sugar residues was estimated by LC-MS. Eight lignan glycosides were found, and they were eluted during reversed-phase HPLC in the expected order. Lignan glycosides could be hydrolyzed with a combination of cellulase and β-glucosidase.

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The enzymatic hydrolysis of lignan glycosides in sesame seed was examined. β-Glucosidase only hydrolyzed sesamolinol glycoside sufficiently. However, all lignan glycosides tested could be hydrolyzed by a combination of cellulase and β-glucosidase. The optimum condition for this reaction was incubation at 50°C for 20 h with a buffer (pH 4.5-5.0). When cellulase was used with β-glucosidase, the amount of lignans obtained was 3 to 10 times the amount obtained without cellulase. The most abundant aglycon of lignan glycosides in sesame seed was sesaminol.

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Hydrostatic pressure of 200-600 MPa was applied to tomato juice in an investigation of the effect of such pressure on sterilization with different antimicrobial substances. Bacillus coagulans was used as the test microorganism added to the tomato juice. Polylysine, protamine, and an extract of etiolated seedlings of adlay (tears) were the antimicrobial substances used. The logarithm of the time of pressure treatment and the logarithm of the bactericidal effect were directly proportional in this range of pressures. Changes with time were examined next. The number of viable bacteria did not change for a few minutes when the pressure was 400 MPa or less. The time before this number began to decrease was inversely proportional to the pressure, but not to the initial number of viable bacteria. When the pressure was 500 MPa or more, the number began to decrease while the maximum pressure had not yet been reached.
When tomato juice containing polylysine or protamine was treated with pressure, the time before the number of bacteria decreased was prolonged, so these substances seemed not to be effective. The effects of hydrostatic sterilization improved when the extract of etiolated seedlings of adlay was present.

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Cyclodextrin inclusion complexes of volatile materials and unstable compounds are in commercial use in the food industry and elsewhere. Their inclusion properties are usually examined by HPLC and GC, for which samples must first be prepared by dissolution and extraction by solvents. We evaluated the use of high-resolution ¹H-NMR for the measurement of guest/host ratios of the inclusion complexes. This method made it possible to estimate the volatility of the compounds incorporated in the complexes and the thermal stability of the complexes. These properties of α- and β- cyclodextrin complexes of pyridine and benzaldehyde were estimated on the basis of changes in the guest/host ratio with storage time and temperature. The relationship between the stability constant of the inclusion complexes and the release properties was not a simple one. β-Cyclodextrin, which has a large space in the molecule, tended to allow an excess of the guest compound to be included, and the oxidation resistance depended on the mode of inclusion.

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Methods of preparation for the measurement of the distribution of pore sizes of tobacco were examined. We expected that drying at the critical point of samples before measurement of the N₂ adsorption isotherm would prevent pore contraction. First, the material was soaked in ethanol, which displaced water in the pores, and then the ethanol was replaced with liquid CO₂. However, this procedure resulted in swelling, contraction, or both; the changes depended on the concentration of the ethanol used to start the displacement. Therefore, a suitable concentration of ethanol was searched for. The amount of adsorbed water was calculated from the pore-size distribution to check the reproducibility of the effects of the preparation method. The values calculated for samples that were dehydrated with 40, 60, or 40 and 60% (w/w) of ethanol in water were in good agreement with the experimental data. Scanning electron micrographs showed that the shape of the samples had changed little compared with untreated samples. We concluded that the range of 40 to 60% (w/w) was the optimum concentration at which to start the displacement of water.

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