Hsian-tsao polysaccharide (HTP) partially purified from Mesona procumbens Hems. promotes gel formation in the presence of added starch. We studied the resulting gel properties when ultrafiltered HTP was used as a new gel-inducing agent. By investigating changes in gel strength and viscoelasticity, we found that gel hardness and viscosity were enhanced by repeated ultrafiltration. Scanning electromicroscopy also revealed that the hard gel displayed dense structures formed within the gel network.

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Menadione-catalyzed luminol chemiluminescence assay was evaluated for rapid detection of coliform bacteria in milk. The assay was evaluated using raw milk (non-pasteurized) samples and pasteurized milk samples spiked with Escherichia coli, Enterobacter aerogenes, Klebsiella oxytoca, Citrobacter freundii. The detection limit in this assay was 10⁵-10⁴CFU/ml using a 96-well plate with BGLB broth. Our study revealed that coliform contamination of 10¹-10⁰CFU/ml of milk could be detected after 18 h of incubation at 35°C in BGLB medium. Moreover, this assay detected gas production in samples of BGLB after only 18h of a 48-h incubation. As this assay is convenient, quick and inexpensive compared to the conventional method, it should be useful for the rapid detection of coliform contamination in pasteurized milk.

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To utilize foliage of sweet potato (Ipomoea batatas L.) as a food material, the functional components of folic acid and polyphenol in foliage (leaf, petiole and stem) of 16 species of Okinawan sweet potato were determined. The amounts of folic acid and polyphenol in eligible parts (leaf and petiole), except in Okinawa 100 species, contained higher amounts than stems and were similar to amounts of spinach. Miyanou 36 had the highest amounts of folic acid. Folic acid in Bise harvested in summer was higher than that of the spring sample. Harukogane contained the highest amounts of polyphenol, while Okihikari and Ayamurasaki had comparatively less polyphenol than other species. Polyphenol content of Bise and Okiyumemurasaki harvested in summer increased 2-3 times compared to spring. The sweet potatoes were cultivated on main Okinawan soils (Jaagaru, shimajiri maaji and kunigami maaji) ; cultivation on shimajiri maaji soil tends to increase the amounts of folic acid and polyphenol in sweet potato foliage in all but a few species. In Okinawa, vegetable shortages occur during summer ; thus, foliage of sweet potatoes such as Bise and Okiyumemurasaki could be used as summer vegetables or processed food materials. These basic data also would provide useful information for the selection and cultivation of suitable sweet potato species.

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Cross-linked starch suspensions sheared at various shear stresses showed two types of flow behavior. One type indicates a behavior of increasing fluidity, which is observed in concentrated suspensions of weakly cross-linked starch. Although sheared granules are smaller than non-sheared granules, the increasing fluidity of cross-linked starch suspensions is explained by the rupture of fully swollen starch granules. As the swollen granules rupture, the flocculation network of the granules decreases, resulting in a decrease in the viscosity and an increase in the fluidity of starch suspensions. Another flow behavior is decreasing fluidity, which is observed in highly cross-linked starch. The decreasing fluidity of cross-linked starch suspensions results from the re-swelling of granules from the application of unheated shear stress. The re-swollen granules enlarge with strong flocculation, resulting in a decrease of fluidity. Hence, the disruption or the re-swelling of sheared granules explains the two types of fluidity observed in cross-linked starch suspensions. A combination of cross-linking level and starch concentration determines the fluidity type of gelatinized suspensions.

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Hepatic disorders were absent in female mice given both a high-fat diet and a drink containing adzuki polyphenol (APP) for seven weeks, with no significant difference observed in the amount of feces between the experimental and control (high-fat diet only) mice. However, the average weight of mice given the APP drink was significantly lower than that of control mice, and the difference in the weight of ovary circumference fat was particularly marked. Additionally, the fat content of the feces of the mice given the APP drink was significantly higher than that of control mice, indicating greater fat elimination via the feces. An in vivo experiment found an inhibitory effect on pancreatic-lipase-activity dependent on an APP concentration with an IC₅₀ of 38.0ppm. Based on these results, it was suggested that in female mice given both a high-fat diet and the APP drink for a long period of time, APP inhibits pancreatic lipase activity, thus blocking the digestion and absorption of dietary fat and promoting fat elimination in the feces, thereby controlling weight gain.

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Samples of sake were lyophilized and pulverized to powder, and DNA extracted by the “enzyme method”. Starch was decomposed by heat-stable alpha-amylase. Protein was successively hydrolyzed by proteinase K with SDS and the resulting solution was centrifuged. As the precipitates were contaminated with color compounds, they were dissolved in cold 70% ethanol to extract DNA for separation as polyphenol and melanoidin. The extracted DNA was purified with neutral phenol solution. Although template DNA preparation from fermented foods has been reported to be difficult, it was possible to extract and purify template DNA that could be amplified by PCR to differentiate material rice cultivars.The STS primers A7, B43 and NG4 were developed to differentiate cultivars of material rice by PCR method using sake as a sample.

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The metal binding ability of proteoglycan (PG) extracted from salmon nasal cartilage was investigated for various metals using a dialysis method. It was suggested that PG could increase the solubility of insoluble FePO₄ and have stronger interactions with Fe³⁺ than xyloglucan and pectin. Although Fe³⁺ formed an insoluble complex with PG at pH 5.5 and 7.4, Fe²⁺ did not bind with PG. Pb²⁺, Zn²⁺ and Cd²⁺ also did not bind with PG. The amounts of Mg²⁺, Ca²⁺ and Fe³⁺ binding with PG per mole of glucuronic acid in PG were 0.13, 0.08 and 1.22 moles, respectively.

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The effect of low-molecular-weight fraction of water-soluble extract (WS-LMF) of an edible algae, Susabi-nori (Porphyra yezoensis), on cell proliferation was examined using various cancer cell lines. WS-LMF was found to inhibit proliferation of human HL-60 leukemia cells and mouse B16 melanoma cells. WS-LMF also inhibited proliferation of HL-60 cells in a dose-dependent manner and was cytotoxic at higher concentration (1000μg/mL). WS-LMF was further fractionated to methanol-soluble and -insoluble fractions. Each fraction inhibited proliferation of HL-60 cells at a different UV spectra, suggesting that multiple anti-proliferation factors toward HL-60 cells are present in WS-LMF.

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