Chinese people have exploited traditional foods through their long history, and developed an abundant food culture. Especially, preserving health by dieting has been an important part of the traditional food culture in China, which is based on the theory of Chinese medicine. Some of the traditional foods are on the verge of being lost, but improvements in traditional foods will benefit agricultural industries, especially those in poor regions. The theories of traditional Chinese healthy food need more systematic study based on modern science and technology. Some of the fermented soybean foods such as sufu and douchi were reported to contain functional materials. We found that isoflavones composition in the fermented food changed during fermentation, which was closely related to ß-glucosidase activity. Through these researches, we can use the wisdom of healthy eating habits accumulated over the centuries as beneficial knowledge for the health of people.

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Respiration rate is the necessary parameter for designing the storage conditions. In the present investigation, the effects of storage temperatures (5, 10, 15, 20, 25ºC) and gas composition on the O₂ consumption and the CO₂ production have been studied by using the flow through system. The ratio of the respiration rate under controlled atmosphere (CA) conditions (1.6 to 20.7% O₂, 0.2 to 10.2% CO₂, balanced with N₂) were calculated against the values under normal air condition. As a result, it was found that a decrease in O₂ concentration suppressed O₂ uptake at each temperature involving an increase of the respiratory quotient. On the other hand, an increase in CO₂ concentration up to 10% suppressed both O₂ uptake and CO₂ output at 5-15ºC with almost a constant respiratory quotient. Thus, low temperature combined with CA having 5-10% CO₂ will be effective to suppress the respiration rate of tree-ripe ‘Irwin' mango fruit, and O₂ should be higher than 5% to avoid anaerobic respiration.

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In this paper, the effects of wind speed, side ventilators and span numbers on gothic type multi-span greenhouse natural ventilation were studied by numerical simulation using the Computational Fluid Dynamics (CFD) approach. The realizable k-ε model was used for the turbulence model in the simulations. The results showed that the maximum greenhouse ventilation rate was achieved when both side and roof vents were used for ventilation. Without the existence of buoyancy effect in the computations, it was found that the ventilation rate increased linearly with the external wind speed in all the cases studied. The ratio of the opening of the ventilator area to the greenhouse floor area, 9.6%, was found to be small compared to the recommended ratios of 15-25%. The results showed that a significant reduction in ventilation rate was determined as the number of spans was increased and an exponential decay explained the relationship between the ventilation rate and the number of spans.

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To establish an insect factory for mass production of useful substances using silkworms, the author developed a silkworm hemolymph collection system to efficiently collect hemolymph from 5th-instar larvae of silkworms, Bombyx mori. The system automatically performs the serial processes of feeding silkworm larvae to the system, incision, collection of hemolymph, and removal of silkworms after hemolymph collection. This system consists primarily of a silkworm feeder, a conveyer chain with holders for the transport of silkworms, a CO₂ laser for infrared laser beam incision of silkworms, a container for hemolymph collection, and two coolers. The hemolymph collection from 4 and 5-day 5th-instar silkworm larvae anesthetized at low temperature could be collected continuously in less than 2.5 min per larva, giving a good prospect for a one-man operation. The amount of hemolymph was 12-13% of the silkworm larva body weight.

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We studied damage to wool fabrics dyed with different natural and chemical dyestuffs by the larvae of varied carpet beetle, Anthrenus verbasci, as part of a study on the functions of natural dyestuffs. Eight of ten natural dyestuffs showed an antifeeding effect against A. verbasci. Strength of the antifeeding effect of natural dyestuffs in a feeding preference test was in the order lac dye, gallnut, catechu, red cabbage, Cricula cocoon extract > cochineal, indigo, Amur cork tree extract > chemical dye. Lithospermi radix and turmeric were less effective against A. verbasci. The damage to dyed fabrics by the insect was not related to the extent of color depth or shade of the dyed fabric. Water-soluble substances having absorption peaks at around 280 nm, commonly were present in the natural dyestuffs except for turmeric. The polyphenols, tannic acid and catechin having absorption peaks at around 280 nm, seemed to be not related with the antifeeding effect. An alkali degummed Cricula cocoon sample that had almost all of the cocoon filament sericin removed showed almost the same level of damage by insect feeding as that of natural Cricula cocoons.

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Percolation of water from a pond may cause a landslide in a hilled rural area. Before measures to prevent such landslides can be planned, it is essential to identify reservoir-water influent from the pond. We describe an analytical method that uses ²²²Rn- and water-balance equations to quantify groundwater effluent and reservoir-water influent simultaneously, which is impossible using the conventional method that measures only surface-water inflow and outflow. We selected F pond, Nagano Prefecture, as the study site. We estimated the rate of ²²²Rn dispersion to the atmosphere by assuming a stagnant film between water and air with thickness inversely proportional to the rate of dispersion. By a laboratory experiment, we estimated the film to be about 830 µm thick and found that the film thickness was not influenced by wind velocities less than 1.5 m s^-1. A preliminary investigation suggested that reservoir-water was mixed very well. The groundwater effluent and the reservoir-water influent during the investigation were calculated to be 0.67 × 10^-3 m³ s^-1 and 0.41 × 10^-3 m³ s^-1 respectively, by making ²²²Rn- and water-balance equations and solving them. This analytical method is expected to be useful for not only prevention of a landslide but also for effective use of water and prediction of water quality.

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Aiming to select suitable strains of lactic acid bacteria for producing yogurt-like functional food from soybean milk, the fermentation properties of 14 lactic acid bacterial strains belonging to genera Bifidobacterium, Lactobacillus, Lactococcus and Streptococcus were evaluated using soybean milk as the culture medium. All 14 strains examined were able to grow in soybean milk. Twelve out of the 14 strains lowered the pH of the medium and produced lactic acid. Tested strains showed a variety of consumption patterns of oligosaccharides and hydrolyzing capacity of isoflavone glucosides. Three strains, Bifidobacterium breve JCM 1192, B. bifidum JCM 1255 and Lb. casei subsp. rhamnosus IFO 3425 exhibited the most promising results. These strains could hydrolyze both daidzin and genistin to corresponding aglycones, and consume raffinose and stachyose in addition to lowering the pH and producing lactic acid.

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It was proved that tea-seed saponins (TSS) showed the growth inhibitory activity to the weed seedlings, early watergrass (Panicum Crus-galli L.), green foxtail (Setaria viridis Beauv. L.) and white clover (Trifolium repens L.) at concentrations more than 10 mg/L. However, this activity was lower than agricultural chemicals. The additive growth inhibitory effect of TSS and glyphosate (isopropylammonium N-(phosphonomethyl)glycinate), which is one of the most popular weed killers in Japan, was investigated to prove that TSS additively increased the growth inhibitory effect of glyphosate to early watergrass seedlings. This result suggests that TSS could be utilized as growth inhibitory agents of weed seedlings in combination with other agricultural chemicals.

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Volatile constituents of the new Japanese tea (Camellia sinensis) clonal cultivar ‘Sofu’, which has a characteristic aroma, were extracted by means of a simultaneous distillation extraction method and analyzed by means of gas chromatography. A peak found in ‘Sofu’, and not in any other tea cultivar that we analyzed, was identified as methyl anthranilate. ‘Sofu’ is a hybrid of ‘Yabukita’ (var. sinensis) and ‘Shizu-Inzatsu 131’, which is derived from a cross between var. assamica and var. sinensis. ‘Shizu-Inzatsu 131’, the pollen parent of ‘Sofu’, also contained methyl anthranilate. Furthermore, ‘Fujikaori’, the hybrid of ‘Shizu-Inzatsu 131’ crossed with ‘Yabukita’ as the pollen parent, contained methyl anthranilate. ‘Shizu-Inzatsu 131’ was selected from a natural cross population of the clonal strain introduced from Assam. These suggest that the origin of tea which contains methyl anthranilate is in var. assamica. This is the first report of methyl anthranilate in Japanese cultivars or native varieties.

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Chlorine-free bleaching was carried out on kraft pulp from oil palm empty fruit bunches (EFB) with an oxygen (O₂) - acid (H₂SO₄) - ozone (O₃) - hydrogen peroxide (H₂O₂) bleaching sequence. The κ-number (= an indicator of lignin content) of the pulp was reduced considerably after these processes indicating that most of the lignin present in the pulp can be removed using this chlorine-free sequence. Handsheets of both bleached and unbleached EFB pulp were prepared and their paper properties were determined. Brightness, a measure of the whiteness of paper, was achieved to ca. 75% for the bleached EFB pulp, showing a possibility of achieving 80% of brightness by chlorine-free bleaching. Paper strengths as indicated by tensile, tear and burst indices as well as stretch did not show significant differences between before and after bleaching. It is notable that these results were obtained despite a large decrease in viscosity by the bleaching process. Moreover, the EFB bleached pulp showed comparable strengths to hardwood pulps, indicating that EFB has the potential as a raw material for chemical pulp production using chlorine-free bleaching sequences.

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