Structural characteristics of resistant starch (RS) were investigated. Tuber starches, hydrolyzed with 1N HCl at 35°C for 8 hr followed by autoclaving-cooling treatment, were heated at 100°C for 16 hr after adjusting the moisture content to 20 or 30%. RS content of the tuber starches ranged from 5.4 to 22.7% depending on the source and type of treatment. Gelatinization parameters of RS isolated from partially acid-hydrolyzed starch with autoclaving-cooling followed by heat-moisture treatment (HMT) showed higher enthalpy (∆H) values and lower peak temperature (T p ) compared with non-acid-hydrolyzed RS. R values, the difference between completion and initial temperatures, and ∆H of RS increased by HMT. The X-ray diffraction patterns of potato and sweet potato RS isolated from partially acid-hydrolyzed starch with autoclaving-cooling showed distinct sharp peaks at 15, 25, 27, and 28°, which decreased by HMT.

A geometric-selective synthesis of (E)-beta-iodo Morita-Baylis-Hillman esters has been developed through a three-component aldol-type reaction using BF3.Et2O and TMS-I. The synthetic utility of the (E)-beta-iodo Morita-Baylis-Hillman esters was demonstrated in the first reported short synthesis of secokotomolide A.

The objective of this study was to investigate technical methods for extraction of mucopolysachharide-protein containing chondroitin sulfate from keel cartilage of chickens. The chemical composition of chicken keel cartilage was determined. For the preparation of mucopolysaccharide-protein from lyophilized chicken keel cartilage, hot water extraction and alcalase hydrolysis methods were examined. Results showed that the optimum condition of hot water extraction was incubation for 120 min with a yield of 40.09% and chondroitin sulfate content of 28.46%. For alcalase hydrolysis, the most effective condition was 2% alcalase in 10 volumes of distilled water for 120 min. The yield of hydrolysate was 75.87%, and chondroitin sulfate content was 26.61%. For further separation of chondroitin sulfate from the alcalase hydrolysate, which has a higher yield than that of hot water, 60% ethanol precipitation was performed. The yield of the ethanol precipitate was 21.41% and its chondroitin sulfate content was 46.31%. The hot water extract, alcalase hydrolysate and ethanol precipitate showed similar electrophoretic migration with standard chondroitin sulfate (chondroitin sulfate A), using cellulose acetate membrane electrophoresis. These results indicated that a significant amount of mucopolysaccharideprotein containing chondroitin sulfate could be acquired form chicken keel cartilage. Therefore, keel cartilage in chicken may provide an inexpensive source of chondroitin sulfate for commercial purposes.

Fermented vegetable juices have gained attention due to their various beneficial effects on human health. In this study, we employed gas chromatography–mass spectrometry, direct infusion-mass spectrometry, and liquid chromatography–mass spectrometry to identify useful metabolites, lipids, and carotenoids in vegetable juice (VJ) fermented with Lactobacillus plantarum HY7712, Lactobacillus plantarum HY7715, Lactobacillus helveticus HY7801, and Bifidobacterium animalis ssp. lactis HY8002. A total of 41 metabolites, 24 lipids, and 4 carotenoids were detected in the fermented and non-fermented VJ (control). The lycopene, α-carotene, and β-carotene levels were higher in VJ fermented with L. plantarum strains (HY7712 and HY7715) than in the control. Proline content was also elevated in VJ fermented with HY7715. Uracil, succinic acid, and α-carotene concentration was increased in VJ fermented with HY7801, while glycine and lycopene levels were raised in VJ fermented with HY8002. This study confirmed that each probiotic strain has distinctive characteristics and produces unique changes to metabolic profiles of VJ during fermentation. Our results suggest that probiotic-fermented VJ is a promising functional beverage that contains more beneficial metabolites and carotenoids than commercial non-fermented VJ.

Comparative genomic analysis was performed on eight species of lactic acid bacteria (LAB)-Lactococcus (L.) lactis, Lactobacillus (Lb.) plantarum, Lb. casei, Lb. brevis, Leuconostoc (Leu.) mesenteroides, Lb. fermentum, Lb. buchneri, and Lb. curvatus-to assess their glutamic acid production pathways. Glutamic acid is important for umami taste in foods. The only genes for glutamic acid production identified in the eight LAB were for conversion from glutamine in L. lactis and Leu. mesenteroides, and from glucose via citrate in L. lactis. Thus, L. lactis was considered to be potentially the best of the species for glutamic acid production. By biochemical analyses, L. lactis HY7803 was selected for glutamic acid production from among 17 L. lactis strains. Strain HY7803 produced 83.16 pmol/μl glutamic acid from glucose, and exogenous supplementation of citrate increased this to 108.42 pmol/μl. Including glutamic acid, strain HY7803 produced more of 10 free amino acids than L. lactis reference strains IL1403 and ATCC 7962 in the presence of exogenous citrate. The differences in the amino acid profiles of the strains were illuminated by principal component analysis. Our results indicate that L. lactis HY7803 may be a good starter strain for glutamic acid production.

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Assessing human exposure to food-borne hazards requires standardized assessment tools. The objective of this study was to validate a newly developed dietary assessment questionnaire to assess human exposure to food-borne hazards, which include dietary behavior and food consumption patterns such as eating frequency, types of food containers and cooking methods. A total of 216 adults were recruited for two questionnaire surveys (questionnaire 1 and 2) about 1 week apart with a 3 day diet record. Reproducibility was evaluated by comparing responses from questionnaires 1 and 2, and validity was checked by comparing responses from questionnaire 2 and the 3 day diet record. Comparisons were based on the percent agreement and Spearman's rank correlation coefficient. The mean exact agreement of food containers at purchase between questionnaires 1 and 2 was 73.5%, for storing containers it was 71.9%, and for cooking methods it was 83.0%. The mean correlation coefficient for food intake frequency between questionnaires 1 and 2 was 0.71 (range, 0.50?0.83). The mean correlation coefficient of the food intake frequency between questionnaire 2 and the 3 day diet record was 0.21 (range, 0.04-0.48). The exact and adjacent agreement of food intake frequency quartile assessed by questionnaire 2 and the 3 day diet record was 65.4% (range, 51.0-82.1%). Although the correlation coefficient for food intake frequency between questionnaire 2 and the 3 day diet record was low, the exact and adjacent food intake frequency agreement was higher than 50% and reproducibility of the dietary behaviors exceeded 70%. Therefore, the questionnaire developed in this study could be applied to assess diets for the human exposure to food-borne hazards as a qualitative assessment in a large population. (Korean J Nutr 2011; 44(2): 171 ~ 180) KEY WORDS: dietary questionnaire, food-borne hazard, exposure assessment, validation.

The aim of this study was to develop a reliable dietary questionnaire to assess human exposure to food-borne hazards. Eleven food-borne hazards were chosen as a priority control list through a literature review and advisory committees. The 11 food-borne hazards were phthalate, aflatoxin, bisphenol A, polycyclic aromatic hydrocarbons, dioxin, polychlorinated biphenyls, mercury, lead, cadmium, arsenic, and acrylamide. The characteristics, exposure level, and paths of these hazards were reviewed, and questionnaire items were identified to assess human exposure from the literature. A questionnaire was developed for each selected food based on its characteristics. Based on the items in the individual questionnaires, a comprehensive questionnaire, which contained demographic characteristics, job information, socioeconomic factors, health related lifestyles, and dietary behaviors, was developed. A 99-item food frequency questionnaire (FFQ) to assess food-borne hazard exposure was also developed. The FFQ included frequency of food intake during the previous year, container type for purchasing and storing food, and cooking method. The questionnaire developed in this study could be applied to assess dietary factors during an exposure assessment of food-borne hazards in a large population. A validation study for the questionnaire is needed before applying it to surveys. (