Resveratrol (RT) has been suggested to have a protective effect against cardiovascular diseases. We analyzed the concentration of RT in red wine samples at early stages of aging and old vintage wines, by a combination of normal and reverse phase HPLC. Although we have previously reported that RT contents in red wine samples, made from eight grapevines grown in Hokkaido, Japan, after malolactic fermentation were generally higher than those measured at the end of alcoholic fermentation, the increasing level of RT in the wines was shown to continue until 8 months after malolactic fermentation accompanied by a decrease in piceid (RT glucoside) probably due to β-glucosidase produced by lactic acid bacteria. During further storage period the RT level was presumed to little change. In analysis of red vintages (from 1982 to 1992) made from the same grapevine, considerable amounts of RT (1.8-3.5mg/l) were present. Although there was a decrease of cis-RT content with aging years, there was no correlation between trans-RT content and aging years, suggesting that trans-RT level in wines would be stable during aging period. The relationship between trans-RT levels in the vintages and weather conditions at the vineyard from June to September of harvest years showed trend where the concentrations of trans-RT decreased when the temperature was high. Thus, it was found that much of the variation in RT content in red wines, reported in the literature, could be partially explained by weather conditions during the grape berry development as well as by intrinsic properties of grapevines from which wines were vinted.

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Kombu (edible Japanese kelp) is a well-known dietary source of iodine and minerals. This is the first report to our knowledge on the identification of the volatile iodine compounds of kombu. Thematerials for this experiment were three kinds of dried kelp: 'Ma kombu' (Laminaria japonica Areschoug), 'Rishiri kombu' (Laminaria ochotensis Miyabe) and 'Mitsuishi kombu' (Laminaria angustata Kjellman). Each kombu was wild and harvested in Hokkaido in 1999, dried in the sun on the ground. Volatiles of kombu were collected using dynamic headspace sampling (DHS) method. In addition, volatiles were isolated by the method of simultaneous distillation and extraction under reduced pressure (SDE). Volatiles were identified by a capillary GC-MS. Four iodides (2-iodopropane, 1-iodopropane, 1-iodopentane and 1-iodooctane) were isolated from each sample by DHS. In DHS, the total number of identified volatile compounds of 'Ma kombu', 'Rishiri kombu' and 'Mitsuishi kombu' were 49, 47 and 41, respectively. The odor description of volatile compounds was investigated using GC equipped with a headspace sampler and a sniffing port. Only 1-iodooctane had the odor in the four kinds of iodides. The odor description of 1-iodooctane was 'like dried kombu with laver' by GC- sniffing. The odor description of some compounds of dried 'Ma kombu' were (E)-2-heptenal (almond-like), nonanal (like dried outer peel of Citrus Unshiu), (E)-2-octenal (like dried kombu with soy sauce), (E)-2-nonenal (like kombu with sour), (E)-2-decenal (like stock made from kombu), 1-octen-3-ol (like dried kombu), (E)-2-octen-1-ol (like mushroom with citrus), (E)-2-nonen-1-ol (like salt-sweet preserve made of kombu). On the other hand, both of 1-iodopropane and 2-iodopropane of all samples were not isolated by SDE. In the SDE extracts, the total number of identified volatile compounds of 'Ma kombu', 'Rishiri kombu' and 'Mitsuishi kombu' were 53, 53 and 48, respectively. The Log odor unit value was calculated from the concentration and the odor threshold value. The following volatile compounds showed the Log odor unit larger than 2 in the 'Ma kombu': 1-iodooctane, nonanal, (E)-2-nonenal, (E, Z)-2, 6-nonadienal, 1-octen-3-ol, (E)-2-nonen-1-ol, (E, Z)-2, 6-nonadien-1-ol, diacetyl and β-ionone. It is supposed that the aroma of 1-iodooctane is one of the most important components of kombu aroma.

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The red pigment from the roots of table beet (Beta vulgaris L.) is commercially used as a food colorant. We established the efficient cell culture system of table beet. The properties and application of the red pigment obtained from the cultured cells as a food colorant were investigated. When the cells of table beet was cultured in the revised Linsmaier-Skoog medium in a 30l jar fermentor under a dark condition for 13 days, the cell yield was 25g dry wt./l and betacyanin content was 0.92%. Heat and light stability of the red pigment from cultured cells were similar to those of the pigment from table beet roots. Fish and pork meat sausages colored with the pigment from cultured cells revealed the similar properties of coloring to those with the pigment from the roots. This study suggested that the red pigment from cultured cells can be used as a food colorant, and this cell culture system of table beet can be available for the stable pigment production on a practical level.

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The author had evaluated the digestion of proteins of parched soybeans by trypsin and observed high digestibility after parching of intact whole soybeans but very low digestibility after parching of crushed soybeans, previously this was because the trypsin inhibitor (TI) that is present in intact whole soybeans is readily inactivated by parching, whereas the TI in crushed soybeans has become thermostable and is not inactivated by parching. In this paper, changes in TI activity after tissue destruction and heating of soybeans were evaluated. The TI activity in parched (150°C, 20min.) intact whole soybeans was decreased by heat to about 1/20 of the initial level. On the other hand, TI activity in soybean flour or soybean flakes was less inactivated with a higher degree of tissue destruction. The TI activity in parched soybean flour with a particle diameter less than 1mm was similar to that in raw soybeans. Proteins in raw soybeans, parched intact whole soybeans, and parched soybean flour were digested with tryp in. The digestion rate increased with the added amount of trypsin even when the amount of trypsin was lower than the unit amount of the residual TI. The digestion rate reached about 50% with an amount of trypsin the same as the unit amount of TI and increased thereafter in proportion to the added amount of trypsin, being the maximum with an amount of trypsin twice the unit amount of TI.

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The vegetables produced in Ei-cho were extracted with ethanol and the inhibitory effects of the ethanol extracts on the growth of HL60 human leukemia cells were examined. We extracted 5 vegetabies (carrot, Welsh onion (2 varieties), Chinese radish, bitter gourd and cabbage) and 4 varieties of sweet potato. Among the extracts, the bitter gourd extract was the most effective inhibitor of the HL60 cell growth. The ethanol extract of bitter gourd induced the apoptotic cell bodies and oligonucleosomal DNA fragmentation in HL60 cells. The resuits indicated that the ethanol extract of bitter gourd induced apoptosis in HL60 cells. The ethanol extract also induced apoptosis in B16 mouse melanoma 4A5 cells. The ethanol extract of bitter gourd was dissolved in hot water and partitioned with ethyl acetate. The ethyl acetate fraction that induced apoptosis in HL60 cells was further fractionated by OASIS HLB column chromatography. Both of the fractions that eluted with 20-40% and 60-80% ethanol induced apoptosis in HL60 cells. The results showed that more than 2 components contained in the bitter gourd extract induced apoptosis in HL60 cells.

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To estimate the radical scavenging activity in various agricultural products, the rapid and reliable method is developed. There have been many methods to measure the radical scavenge activities so that it's been difficult to compare the data between different methods. In this study, because the method uses 96-well-plate, it can be carried out by a very small quantity, half-automated. And the radical scavenge activity is estimated by two methods based on different principle, so that the data can be reliable. In this study, about 200 agricultural products were measured. As a result we can gain the data library that is helpful for not only researchers but also farmers and consumers.

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We have proposed a freeze cutting method in which a three point bending load is applied on a frozen fish body to cut in round slices. Lowering the three-point bending load can facilitate the freeze cutting processing. Based on the idea that a notch in the fish body may lower the cutting load, the effect of introducing a notch was examined with respect to cutting stress and smoothness of cut surface in model fish meat and in saury. It was found that the introduced notch effectively lowered the cutting stress in both the model fish and saury, and that the smoothness of cut surface was improved. This study also showed the possibility that a sharper notch could attain lower cutting stress.

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Determination of the melting temperature of fats and oils was attempted by measuring electric capacity (capacitance). Olive oil, soybean oil, rapeseed oil, peanut oil, corn oil, sesame oil and triolein were used as samples. Capacitance change with melting of samples was measured in the temperature range, -160-30°C using a capacitance meter. Differential scanning calorimetry (DSC) was also used to examine the enthalpy change accompanying the melting. The capacitance of the fat and oil samples increased with increasing temperature. The temperature dependency curve of capacitance of each sample had a unique inflection point, though similar in its shape in all samples. The change in capacitance was remarkable around the melting point of each sample. The change in capacitance corresponding to temperature change was differentiated by the temperature increment, and the first derivative curve of capacitance thus obtained was quite similar to the DSC curve. Initial, peak and end temperatures of melting were read from the first derivative curve of capacitance and the DSC curve. These melting temperatures obtained from the capacitance measurement was consistent with those from DSC, thus suggesting that the melting temperatures of fats and oils can be determined accurately by measuring capacitance.

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The pyrolysis of expanded polystyrene (EPS) with 2, 4-diphenyl-4-methyl-1-pentene (MSD) as an additive was studied at a temperature about 200°C. In the time, the scale of EPS was increased in steps from 0.25g to 10g. We found that it was important to control the temperature in the reaction vessel because the temperature gradient of gas-phase and liquid-phase enlarged with an increase in the scale of EPS, and it was also necessary to remove the residual oxygen in the reaction vessel during the pyrolysis. The most efficient molar ratio of MSD to EPS decreased with an increase in the scale of EPS, but the absolute weight of MSD did not change.

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Distribution of strophanthidin glycosides (STRO) and digitoxigenin glycosides (DIGI) in seeds and leaves of Corchorus olitorius, and in its products (powder, drink and noodle) were investigated. Both STRO and DIGI were present in all of the seeds. There was little detectable difference in content of these glycosides in the seeds with regard to the country of their origin. And these glycosides were not detected in all of the leaves and its commercial products. Analysis of STRO and DIGI in the different stages of growth of Corchorus olitorius, and the seeds of the next generation revealed that STRO and DIGI were present not only in the seeds, but also in the seed leaves and the non-maturing pods. A caution has to be exercised in harvesting leaves of Corchorus olitoriuse not to immix its seed leaves and pods in kitchen gardens.

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