Key Nutrients (key + nutrient)

Distribution by Scientific Domains


Selected Abstracts


Taking an Undergraduate Nutrition Course Results in Favorable Attitudes Toward a Healthful Diet and Improved Intake of Several Key Nutrients

FAMILY & CONSUMER SCIENCES RESEARCH JOURNAL, Issue 1 2009
Roman Pawlak
The purpose of this research was to assess the impact of introductory undergraduate nutrition course on students' attitudes toward healthy diet and on students' intake of nutrients. A pre and post-test design was used to assess changes in self-reported nutrient intake. Open-ended questions were asked to elicit responses about how/whether the course had any impact on their attitudes toward foods and dietary behavior. A statistically significant increase in fiber, folate, potassium, and calcium intake were observed, comparing post to pre-test. A decrease in saturated fat intake in terms of energy percentage was observed. Increased awareness of the impact of diet on health was reported by students. A desire to increase intake of fruits, vegetables, and whole grains, and to decrease intake of fat and sugar was also reported. Students reported a willingness to eat less fast food and candies as well as drink fewer sodas. Thus, in this study a college nutrition course did effectively increase awareness of a healthy diet as well as change in attitude and modify dietary behavior. [source]


Complex responses to culture conditions in Pseudomonas syringae pv. tomato DC3000 continuous cultures: The role of iron in cell growth and virulence factor induction

BIOTECHNOLOGY & BIOENGINEERING, Issue 5 2010
Beum Jun Kim
Abstract The growth of a model plant pathogen, Pseudomonas syringae pv. tomato DC3000, was investigated using a chemostat culture system to examine environmentally regulated responses. Using minimal medium with iron as the limiting nutrient, four different types of responses were obtained in a customized continuous culture system: (1) stable steady state, (2) damped oscillation, (3) normal washout due to high dilution rates exceeding the maximum growth rate, and (4) washout at low dilution rates due to negative growth rates. The type of response was determined by a combination of initial cell mass and dilution rate. Stable steady states were obtained with dilution rates ranging from 0.059 to 0.086,h,1 with an initial cell mass of less than 0.6,OD600. Damped oscillations and negative growth rates are unusual observations for bacterial systems. We have observed these responses at values of initial cell mass of 0.9,OD600 or higher, or at low dilution rates (<0.05,h,1) irrespectively of initial cell mass. This response suggests complex dynamics including the possibility of multiple steady states. Iron, which was reported earlier as a growth limiting nutrient in a widely used minimal medium, enhances both growth and virulence factor induction in iron-supplemented cultures compared to unsupplemented controls. Intracellular iron concentration is correlated to the early induction (6,h) of virulence factors in both batch and chemostat cultures. A reduction in aconitase activity (a TCA cycle enzyme) and ATP levels in iron-limited chemostat cultures was observed compared to iron-supplemented chemostat cultures, indicating that iron affects central metabolic pathways. We conclude that DC3000 cultures are particularly dependent on the environment and iron is likely a key nutrient in determining physiology. Biotechnol. Bioeng. 2010;105: 955,964. © 2009 Wiley Periodicals, Inc. [source]


Exploring the nutrition and lifestyle knowledge, attitudes and behaviour of student home economics teachers: baseline findings from a 4-year longitudinal study

INTERNATIONAL JOURNAL OF CONSUMER STUDIES, Issue 4 2008
Mary Isobelle Mullaney
Abstract It is widely acknowledged that obesity linked with reduced exercise contributes to health problems, and that, conversely, individuals who embark on weight reducing diets may become deficient in key nutrients. It is often advocated that these problems, which can be grouped together as poor dietary practice, be tackled through education. This study attempts to examine the relationship between nutrition education and lifestyle behaviours in a select group of third level students. The Irish Home Economics curriculum aims to teach secondary school pupils about nutrition and lifestyle practices conducive to health. However, the attitudes and lifestyle practices of those teaching this subject have never been examined in Ireland. The purpose of the present 4-year longitudinal study, whose first year findings are presented here, is to investigate the nutrition and lifestyle knowledge, attitudes and behaviours of a cohort of Irish student home economics teachers over the 4 years of their Bachelor of Education (Home Economics) degree course. The study was designed to explore possible changes in knowledge, attitudes and practices over the course of their professional education. Nutritional knowledge was measured using a 220-question adapted version of the test devised by Parmenter and Wardle. Attitudes were measured using a questionnaire adapted from the Pan-EU Survey on Consumer Attitudes to Physical Activity, Body-weight and Health. Food, alcohol consumption and exercise were measured using a 7-day reported dietary/exercise diary. Nutrient intake data were determined using dietary analysis. Weight, height and waist circumference were measured and body mass index (BMI) calculated. When starting college, student home economics teachers have broadly similar anthropometric, dietary and lifestyle characteristics to those of their contemporaries. Mean BMI was identical [24.4 kg/m2 (SD 4.3)] to that reported in the North/South Ireland Food Consumption Survey (NSIFCS) for those aged 18,35 years, although energy intakes were significantly higher in the cohort of student teachers (P = 0.000). Thirty-eight per cent were overweight or obese vs. 33.6% in the NSIFCS. Only 17% (n = 6) of students achieved an intake of 300 µg/day of folate as recommended by the Food Safety Authority of Ireland and only one the recommended intake of non-starch polysaccharides (18 g/day). One in three students in this study smoke (16 of 48) and alcohol consumption was high. Only one student was very active. Students scored a mean of 55% (SD 8%) on the knowledge test, with similar scores attained for specific aspects of nutritional knowledge (i.e. food groups, constituents of foods, current dietary advice, nutrients, lifestyle practices). However, knowledge of nutrition definitions was weaker with a mean score of 31% (SD 8.6%). Students had a positive attitude towards food choice, the link between food and health and control over their own diet. Similar attitudes towards exercise, smoking and alcohol consumption were displayed despite students perceiving themselves as not having a balanced diet, having insufficient exercise and having regretted something done as a result of consuming alcohol. They appear to display optimistic bias in relation to health risks. These findings provide baseline data for the longitudinal study and indicate that those choosing to pursue a career as a home economics teacher in Ireland have similar nutritional and lifestyle characteristics to those of their contemporaries. [source]


Correlates of biological soil crust abundance across a continuum of spatial scales: support for a hierarchical conceptual model

JOURNAL OF APPLIED ECOLOGY, Issue 1 2006
MATTHEW A. BOWKER
Summary 1Desertification negatively impacts a large proportion of the global human population and > 30% of the terrestrial land surface. Better methods are needed to detect areas that are at risk of desertification and to ameliorate desertified areas. Biological soil crusts are an important soil lichen-moss-microbial community that can be used toward these goals, as (i) bioindicators of desertification damage and (ii) promoters of soil stability and fertility. 2We identified environmental factors that correlate with soil crust occurrence on the landscape and might be manipulated to assist recovery of soil crusts in degraded areas. We conducted three studies on the Colorado Plateau, USA, to investigate the hypotheses that soil fertility [particularly phosphorus (P), manganese (Mn) and zinc (Zn)] and/or moisture limit soil crust lichens and mosses at four spatial scales. 3In support of the soil fertility hypothesis, we found that lichen,moss crusts were positively correlated with several nutrients [Mn, Zn, potassium (K) and magnesium (Mg) were most consistent] at three of four spatial scales ranging from 3·5 cm2 in area to c. 800 km2. In contrast, P was negatively correlated with lichen,moss crusts at three scales. 4Community composition varied with micro-aspect on ridges in the soil crust. Three micro-aspects [north-north-west (NNW), east-north-east (ENE) and TOP] supported greater lichen and moss cover than the warmer, windward and more xeric micro-aspects [west-south-west (WSW) and south-south-east (SSE)]. This pattern was poorly related to soil fertility; rather, it was consistent with the moisture limitation hypothesis. 5Synthesis and application. Use of crusts as desertification bioindicators requires knowledge of a site's potential for crust cover in the absence of desertification. We present a multi-scale model of crust potential as a function of site properties. Future quantitative studies can use this model to guide sampling efforts. Also, our results suggest new directions in restoration research: enhancement of moisture residence time and fertilization with key nutrients (Mn, Zn, K and Mg). Re-establishment of soil crusts in desertified lands will help regain lost soil stability and fertility, and facilitate plant re-establishment. [source]


Essential fatty acid enrichment of cultured rotifers (Brachionus plicatilis, Müller) using frozen-concentrated microalgae

AQUACULTURE NUTRITION, Issue 4 2009
L.H. SEYCHELLES
Abstract There is a growing interest in preserving microalgal preparations to maintain constant properties over a long period. The aim is to ensure sufficient delivery of essential fatty acids (and other key nutrients) to mollusc and crustacean larvae and to zooplankton used as live prey in the first feeding of fish larvae. For example, the rotifer Brachionus plicatilis has to be enriched with polyunsaturated fatty acids (PUFA) prior to fish feeding. We used four microalgal species [Isochrysis galbana (T-ISO), Chaetoceros muelleri (CHGRA), Pavlova lutheri (MONO), and Nannochloropsis sp.] both as fresh culture or in a frozen-concentrated form to enrich rotifers. Overall, rotifers had similar relative fatty acid levels when fed the frozen-concentrated or fresh microalgal diets. The levels of 20:4n-6, 22:6n-3, and 20:5n-3 between B. plicatilis and the microalgal diets were linearly correlated. The fatty acid 20:4n-6 was the most readily assimilated: the content found in rotifers reached half the level measured in the microalgal diets. Our results indicate that both the fresh and frozen-concentrated forms of the four microalgal species can be used to enrich PUFA levels in rotifers. Further experiments should be conducted to test if assimilation differs when rotifers are enriched with mono- or multispecific microalgal preparations. [source]