The enzymatic oxygenation of linoleic acid leads to the production of 13-hydroxyoctadecadienoic acid (13-HODE). Subsequent dehydrogenation of 13-HODE by the NAD(+)-dependent 13-HODE dehydrogenase results in the formation of the 2,4-dienone 13-oxooctadecadienoic acid (13-OXO). These oxidized derivatives of linoleic acid have been shown to be involved in several cellular regulatory processes. In the present study, we have examined the enzymatic and nonenzymatic reaction of 13-OXO with glutathione (GSH) and N-acetylcysteine (N-AcCySH). Nonenzymatic reaction rates were determined spectrophotometrically and exhibited a pH optimum of 9.0 which is consistent with attack of a thiolate anion. Product formation was evaluated by reverse-phase HPLC which showed formation of one major product upon reaction with either GSH or N-AcCySH. The HPLC-purified products were examined by FAB MS as well as one- and two-dimensional NMR. The products, with either GSH or N-AcCySH, were found to consist of an equal mixture of two diastereomers arising from addition of a thiolate to the 9 position of 13-OXO. Using GSH as the thiol, the reaction was also shown to be catalyzed by rat glutathione transferase 8-8. In the case of the enzymatic reaction there is stereoselective product formation. Furthermore, submicromolar concentrations of the 13-OXO-GSH conjugate were shown to significantly inhibit glutathione transferase activity in HT-29 homogenates. These investigations provide insight into the potential metabolic disposition of linoleate oxygenation products.

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We developed a short food behavior checklist (FBC) to evaluate the impact of nutrition education on fruit and vegetable intake among ethnically diverse women in the Food Stamp Nutrition Education Program (FSNEP) and the Expanded Food and Nutrition Education Program (EFNEP). To validate the FBC, interviewers collected three 24-hour dietary recalls as well as responses to 11 FBC behavioral questions about fruits and vegetables from 100 English-speaking, low-income women at baseline. A randomly selected subgroup (n = 59) provided a blood sample for analysis of total serum carotenoids at baseline and follow-up. After 6 hours of nutrition education, the treatment group reported significant improvements in three of the seven FBC questions related to fruit and vegetable intake, while no significant changes occurred in the control group. All seven FBC questions were significantly correlated with total serum carotenoids. This short, culturally neutral FBC is a valid and reliable indicator of fruit and vegetable consumption. Compared with the 24-hour dietary recall, it is also less time-consuming to administer, code and analyze, with a reduced respondent burden. UCCE nutrition educator lan Nguyen addresses a class at Fremont Adult school. In California two such programs, EFNEP and FsNEP, together evaluate the nutrition education received by 21,000 low-income families each year.

Although the importance of diet quality was identified more than 120 years ago, it was nearly 60 years before the specific quantitative nutrient needs for humans were determined. Dr Doris Howes Calloway, a nutrition professor at the University of California in Berkeley, established a metabolic unit for studying human nutrient requirements. This article reviews the early origins of human nutrition research and the unique contributions of Dr Calloway worldwide. Nutr Today 2022;57(3):159-165 ORIGINS OF HUMAN NUTRITION RESEARCHHuman nutrition research in the United States has its roots in the US Department of Agriculture where W.O. Atwater 1 developed the bomb calorimeter to measure energy expenditure in humans. He described the need for a calorim-eter over 120 years ago as necessary because many are addicted to the habit of overeating. Thus, concerns about overeating formed the basis for human nutrition research in the late 1890s. Atwater was the first to develop nutritional sciences in the United States. All of the previous work had been conducted in Europe where Atwater trained with Voit (1831Voit ( -1908, who recognized that the oxidation of protein, carbohydrate, and fat provided the energy needed to support metabolism as well as physical activity. After returning to the United States in 1888, Atwater became the chief of the newly formed Office of Experiment Stations within the United States Department of Agriculture (USDA). Atwater also was a professor of chemistry at Wesleyan University. This dual appointment with the USDA and the university became the basis for nutrition research within experiment stations at land-grant universities that still continues today. With assistance from others who were physicists, including E.B. Rosa and J.F. Snell, Atwater constructed the first calorimeter in the United States that was used to determine the energy requirements of humans. 2 The initial calorimeter was built at the Cornell Medical College to determine the energy needs of babies and small animals. A second larger calorimeter to study adults was built at The Pennsylvania State University. 3 These early scientists described the basic laws for deriving energy from food that are still valid today. For example, the primary law is "the nutrients of the food combine within the body with oxygen of the air and undergo combustion, thus liberating energy for the body."Human nutrition research had its roots in the late 1890s to address concerns about overeating.After initially recognizing the dietary need for energy, scientists quickly identified the dietary need for vitamins and minerals. 2 At the beginning of the 20th century, only 3