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PubMed2003

Solubilization of carotenoids from carrot juice and spinach in lipid phases: I. Modeling the gastric lumen.

Our understanding of the factors determining the bioavailability of carotenoids from fruits and vegetables is poor. The apolar nature of carotenoids precludes their simple diffusion from the food structure to the absorption site at the enterocyte. Therefore, there is interest in the potential pathways for solubilization in the gut before absorption. We have studied the transfer of carotenoids from carrot juice and homogenized spinach into lipid phases that mimic the intestinal lumen at the start of digestion. In this paper we report on their transfer into olive oil under conditions pertaining to the gastric environment. A comparison between preparations of raw spinach and of carrot, in which the intact cells have been largely broken, suggests that the membrane-bound carotenoids of spinach are more resistant to transfer than the crystalline carotenoids of carrot. Lowering the pH and pepsin treatment enhance the transfer from raw vegetables. The process of blanching and freezing spinach destroys the chloroplast ultrastructure and leads to (i) a substantial increase in transfer of the carotenoids to oil and (ii) an attenuation or reversal of the enhancement of transfer seen with reduced pH or with pepsin treatment. Similar effects are seen after blanching carrot juice. Our results show that removal of soluble protein and denaturation of membrane proteins enhances the partition of carotenoids into oil. For both vegetables there is no evidence of preference in the extent of transfer of one carotenoid over another. This suggests that partitioning into oil under gastric conditions is not the stage of digestion that could lead to differences in carotenoid bioavailability.

Biological Availability↗

PubMed2004

Ecological correlates of abundance in the Tana mangabey (Cercocebus galeritus).

I investigated the ecological correlates of abundance in the Tana mangabey (Cercocebus galeritus), one of the world's most endangered primates, with the goal of recommending management strategies. I systematically selected 31 forest fragments throughout the mangabey's 60-km distribution along the lower Tana River in southeastern Kenya. Within the 31 fragments, I measured vegetation structure, food abundance, and human forest product use in 107 belt transects, and conducted 370 mangabey surveys. I used a weighted multiple regression analysis to determine whether there was a dependence between the selected forest attributes and the mean number of mangabey groups per fragment. Fragment area and density of trees > or =10 cm diameter at breast height (DBH) were the only variables that significantly correlated with the variation in mangabey abundance. No additional variables were significant when the analysis was limited to forest fragments inside the Tana River Primate National Reserve (TRPNR) or to fragments outside the TRPNR. When I estimated the resources available before recent human forest product use by adding nonharvested and harvested variables, the total basal area of the top 15 food species became significant. This was only within the TRPNR, however. Management, therefore, should focus on increasing forest area, density of trees > or =10 cm DBH, and coverage of food trees throughout the mangabey's distribution. Solutions must be found for the problem of forest clearing, and forest product use must be better managed to protect the habitat of this critically endangered primate. The significance of food abundance only within the TRPNR suggests a need to collect dietary data from mangabey groups in fragments toward the southern limit of the mangabey's distribution, where plant species composition differs from that in fragments in which dietary data have been previously collected.

Animals↗

PubMed2001

A case-control study of gastric cancer in Venezuela.

A case-control study to evaluate risk factors for gastric cancer was carried out among 292 cases of gastric cancer and 485 controls in a high-risk area of Venezuela. Subjects were interviewed using a structured questionnaire, which elicited information on residential history, socio-economic status, family history of gastric diseases, smoking, drinking and dietary habits. Habitual diet was estimated from a meal-structured food frequency questionnaire on 75 food items. There was a strong inverse association with social class, as measured by education and by indicators of poverty. The results of the dietary analysis suggest that a diet high in starch and low in meat, fish and fresh vegetables increases risk of gastric cancer. A protective effect was observed for frequent consumption of allium vegetables. Inverse associations were found with height, which may reflect nutritional status in childhood, and with refrigerator use in the first two decades of life. Alcohol and tobacco consumption was investigated among males only, since the prevalence of alcohol and tobacco use was very low in females. Alcohol drinkers were at higher risk than non-drinkers and there was a small excess risk for current smokers compared with never smokers. There was some evidence of familial aggregation of gastric cancer. These findings will have important implications in planning preventive strategies for gastric cancer in Venezuela.

Adult↗

PubMed2005

Dietary fibre, glycaemic response, and diabetes.

The much publicised global trend in rising levels of obesity and diabetes has refuelled interest in the dietary intake of the macronutrients (fat, protein, and carbohydrates) necessary to maintain the state of normalcy (good health) of an individual. Both scientific and public attention have focused on the dietary mediation of chronic health syndromes, either through use of dietary supplements, or a review of the whole diet situation. Dietary supplements have been used extensively both as pharmacological supplements, food ingredients, in processed foods to aid weight control, and the regulation of glucose control for diabetic patients. Particular interest has focused on the use of dietary fibres, especially soluble dietary fibres (such as guar gum, locust bean gum, and psyllium fibres), resistant starch, and slowly digestible carbohydrates. These have been shown to alter food structure, texture, and viscosity, and hence the rate of starch degradation during digestion. Research has also illustrated an association between the rate of carbohydrate degradation during digestion, and the regulation of postprandial blood sugar and insulin levels. The current paper explores the potential use of dietary fibres in the treatment of obesity and diabetes.

Blood Glucose↗

PubMed1988

Intraoral mucosal reconstruction with microvascular free jejunal autografts: an experimental study.

This experimental study investigated the problem of covering bare bone adequately in the oral cavity to provide a stable, functionally acceptable reconstruction. In eight dogs, intraoral mucosal defects were created whilst preserving the mandibular arch. The defects were reconstructed with a microvascular jejunal patch. Six animals had their reconstructions stressed postoperatively by the administration of irradiation and by feeding solid food. Two control dogs did not receive irradiation. Grafts were assessed clinically and histologically for 6 months. Rapid mucosal healing occurred in seven of eight dogs. The grafts conformed well to the mandibular contour and were tolerant of postoperative radiotherapy and the chewing of solid food. Structural integrity of seven grafts was maintained although subtotal villous atrophy occurred in irradiated grafts and to a lesser extent in control grafts. In one animal whose graft mucosa sloughed, the wound was re-epithelialized from the adjacent buccal mucosa. Microvascular jejunal patches therefore provided a durable, functionally adequate reconstruction of the mouth floor.

Animals↗

PubMed2005

Biodiversity in model ecosystems, I: coexistence conditions for competing species.

This is the first of two papers where we discuss the limits imposed by competition to the biodiversity of species communities. In this first paper, we study the coexistence of competing species at the fixed point of population dynamic equations. For many simple models, this imposes a limit on the width of the productivity distribution, which is more severe the more diverse the ecosystem is (1994, Theor. Popul. Biol. 45, 227-276). Here we review and generalize this analysis, beyond the "mean-field"-like approximation of the competition matrix used in previous works, and extend it to structured food webs. In all cases analysed, we obtain qualitatively similar relations between biodiversity and competition: the narrower the productivity distribution is, the more species can stably coexist. We discuss how this result, considered together with environmental fluctuations, limits the maximal biodiversity that a trophic level can host.

Animals↗

PubMed2002

Interaction between protein allergens and model gastric emulsions.

The observed resistance to pepsinolysis of known food allergens has been suggested as a predictor of their allergenic risk. Consequently, resistance to pepsinolysis has become incorporated into decision tree assessment for potential allergenic risk posed by novel foods. However, existing methods take little account of the interaction between food structure and physiological conditions existing during digestion in vivo. Here we show that a range of protein allergens can adsorb to model stomach emulsions, providing a further means of resisting digestion. We also show that raising the pH and the addition of bile salts to a model stomach emulsion, thereby mimicking the duodenal environment, has the effect of desorbing the adsorbed protein.

Adsorption↗

PubMed1977

[The effect of nutritional factors on the ruminal mucosa. 3. Condition of the mucosa after infusion of propionic acid, acetic acid and butyric acid].

Three non-lactating cows (Deutsches Schwarzbuntes Rind) with large ruminal fistulas were fed coarsely structured food. Within a trial period of 21 weeks infusion periods lasting 3 weeks alternated with equally long control periods (K). During the 3 infusion periods, 8.4 mMol of propionic acid (P), 14.8 mMol of acetic acid (E) and 4,5 mMol of butyric acid (B) per kg liveweight per day were administered through the fistula, the total quantity being 19 litres of solution. In the periods K1...4 the ruminal fluid contained an average of 68 Mol% E, 19 Mol% P, 13 Mol% B (maximum of 10.25 mMol free fatty acids (FFS) per 100 ml, minimum pH 6.4). In the course of the 10 hrs of infusion the Mol percentages of the particular acids infused increased to 27% P (maximum of 11.14 mMol FFS per 100 ml, minimum pH 6.4) or 79% E (maximum of 12,99 mMol FFS per 100 ml, minimum pH 6.0 (5.5)) or 25% B (maximum of 10.34 mMol FFS per 100 ml, minimum pH 6.0 (5.5)). Infusions of E and B had the most pronounced effect on the ruminal mucosa compared with the K periods. All fatty acids increased the process of keratinization and decreased the size of cell nuclei in the stratum basale. As specific effect, P infusions produced a thickening of the lamina propria; B infusions caused a thickening of the stratum germinativum (proliferative effect) while e infusions led to a drastically reduced thickness of villi (antiproliferative effect) due to reductions in the stratum germinativum and the lamina propria. According to the morphological situation high specific mucosal function is suggested during the B-period. The mucosa appeared quite normal during all periods investigated, with the exception of the E period, where hyperkeratosis, atrophy and necrosis were observed in 34% of the sample. Changes in the state of the mucosa appeared as early as 1 week after the beginning of the respective trial periods. Keratin consolidation was the primary cause for chemically induced keratosis. The development of hyperkeratosis seemed to be favoured if low pH values occurred in the rumen in combination with small amounts of metabolites inducing proliferation, both representing synergistic factors.

Acetates↗

PubMed2001

Measurements of the gastric emptying rate by use of ultrasonography: studies in humans using bread with added sodium propionate.

BACKGROUND: Foods with a low glycemic index are increasingly being acknowledged as beneficial for individuals with disorders related to the insulin resistance syndrome. The presence of certain salts of organic acids has been shown to lower the glycemic index of bread products and one of the suggested mechanisms is a lowered gastric emptying rate (GER). One obvious pitfall with many of the common techniques for GER measurement is that the food structure, and hence the gastric release of nutrients, may be affected by enclosure of the marker for gastric emptying, eg, paracetamol. Ultrasonography is a noninvasive method for which the above pitfall is to a large extent avoided. OBJECTIVE: The main objective was to evaluate the use of ultrasonography to determine whether the lowered glycemic and insulinemic responses to bread ingestion after the addition of sodium propionate are explained by a specific effect of propionate on the GER. DESIGN: The effect of sodium propionate in bread was evaluated in 9 healthy volunteers. Barley bread products, with or without added sodium propionate, were ingested as breakfast after an overnight fast. The GER was monitored for 2 h by ultrasonography; during this period, capillary blood was withdrawn repeatedly for measurement of blood glucose and insulin. RESULTS: The GER of the barley bread decreased markedly after the addition of sodium propionate and was accompanied by lowered glycemic and insulinemic responses. CONCLUSION: The lowered glycemic response to ingestion of bread with added sodium propionate appears to be related to a lowered GER.

Adolescent↗

PubMed2000

Diet and stomach cancer: a case-control study in South India.

A prospective case-control study was conducted in Trivandrum, India, to evaluate the dietary risk factors for stomach cancer. One hundred and ninety-four patients with stomach cancer registered at the Regional Cancer Centre (RCC), Trivandrum, Kerala, India, during the period 1988-1991 were considered as cases. A minimum of one control (n = 305), matched for age (+/- 5 years), sex, religion and residential area was selected from the visitors to RCC during the same period. Interviews were carried out using a predetermined structured food frequency questionnaire. The information collected also included socio-demographic/economic background, tobacco chewing, tobacco smoking and alcohol habits. Data were analysed using a multiple logistic regression model. Odds ratios for all dietary variables were estimated. Increased risks were observed with higher consumption of rice (OR 3.9; 95% CI 1.6-10.0). Risk was high for those consuming spicy food (OR 2.3; 95% CI 1.1-5.0), high consumption of chilli (OR 7.4; 95% CI 4.0-13.5) and consumption of high-temperature food (OR 7.0; 95% CI 3.7-12.9). On multivariate analysis, high consumption of rice, high consumption of chilli and consumption of high-temperature food were found to be independent risk factors.

Adult↗

PubMed2025

Spatial Metabolomics Reveals the Role of Penicillic Acid in Cheese Rind Microbiome Disruption by a Spoilage Fungus.

Microbial interactions in cheese rinds influence community structure, food safety, and product quality. But the chemical mechanisms that mediate microbial interactions in cheeses and other fermented foods are generally not known. Here, we investigate how the spoilage mold Aspergillus westerdijkiae chemically inhibits beneficial cheese-rind bacteria using a combination of omics technologies. In cheese rind community and co-culture experiments, A. westerdijkiae strongly inhibited most cheese rind community members. In co-culture with Staphylococcus equorum, A. westerdijkiae strongly affected bacterial gene expression, including upregulation of a putative bceAB gene cluster that is associated with resistance to antimicrobial compounds in other bacteria. Mass spectrometry imaging (MSI) revealed spatially localized production of secondary metabolites, including penicillic acid and ochratoxin B at the fungal-bacterial interface. Integration of LC-MS/MS and genome annotations confirmed the presence of additional bioactive metabolites, such as notoamides and circumdatins. Fungal metabolic responses varied by bacterial partner, suggesting species-specific chemical strategies. Notably, penicillic acid levels increased 2.5-fold during interaction with Brachybacterium, and experiments with purified penicillic acid showed inhibition of a range of cheese rind bacteria. These findings show that A. westerdijkiae deploys a context-dependent arsenal of mycotoxins and other metabolites, disrupting microbial community assembly in cheese rinds.

Aspergillus westerdijkiae↗

PubMed1995

Randomised trial of lipid lowering dietary advice in general practice: the effects on serum lipids, lipoproteins, and antioxidants.

OBJECTIVE: To determine the relative efficacy in general practice of dietary advice given by a dietitian, a practice nurse, or a diet leaflet alone in reducing total and low density lipoprotein cholesterol concentration. DESIGN: Randomised six month parallel trial. SETTING: A general practice in Oxfordshire. SUBJECTS: 2004 subjects aged 35-64 years were screened for hypercholesterolaemia; 163 men and 146 women with a repeat total cholesterol concentration of 6.0-8.5 mmol/l entered the trial. INTERVENTIONS: Individual advice provided by a dietitian using a diet history, a practice nurse using a structured food frequency questionnaire, or a detailed diet leaflet sent by post. All three groups were advised to limit the energy provided by fat to 30% or less and to increase carbohydrate and dietary fibre. MAIN OUTCOME MEASURES: Concentrations of total cholesterol and low density and high density lipoprotein cholesterol after six months; antioxidant concentration and body mass index. RESULTS: No significant differences were found at the end of the trial between groups in mean concentrations of lipids, lipoproteins, and antioxidants or body mass index. After data were pooled from the three groups, the mean total cholesterol concentration fell by 1.9% (0.13 mmol/l, 95% confidence interval 0.06 to 0.22, P < 0.001) to 7.00 mmol/l, and low density lipoprotein cholesterol also fell. The total carotenoid concentration increased by 53 nmol/l (95% confidence interval 3.0 to 103, P = 0.039). CONCLUSIONS: Dietary advice is equally effective when given by a dietitian, a practice nurse, or a diet leaflet alone but results in only a small reduction in total and low density lipoprotein cholesterol. To obtain a better response more intensive intervention than is normally available in primary care is probably necessary.

Antioxidants↗

PubMed2001

Antibacterial activity of S-methyl methanethiosulfinate and S-methyl 2-propene-1-thiosulfinate from Chinese chive toward Escherichia coli O157:H7.

S-Methyl methanethiosufinate (1) and S-methyl 2-propene-1-thiosulfinate (2) were easily seperated from Chinese chive (Allium tuberosum L.) using simple column chromatography. Both compounds showed significant antibacterial activities against E. coli O-157:H7 including spoilage microorganism in food. Structural assignment was based on Mass and NMR-spectroscopic methods.

Allium↗

PubMed2006

Dietary fat intake predicts 1-year change in body fat in adolescent girls with type 1 diabetes.

OBJECTIVE: The purpose of this study was to determine whether objectively measured physical activity and dietary macronutrient intake differentially predict body fat in adolescent girls with type 1 diabetes and control girls. RESEARCH DESIGN AND METHODS: This study comprised 23 girls (12-19 years) with type 1 diabetes and 19 age-matched healthy control girls. At baseline, physical activity and energy intake were assessed for 7 consecutive days by accelerometry and a structured food diary, respectively. Body composition was measured by dual-energy X-ray absorptiometry at baseline and after 1 year. RESULTS: Fat intake was positively related to a 1-year change in percentage body fat (P = 0.006), after adjustment for total energy intake. No significant interaction was observed (case-control group x main exposure), indicating that the association between fat intake and gain in body fat was similar in both groups. Physical activity did not predict gain in body fat; however, total physical activity was positively associated with a gain in lean body mass (P < 0.01). Girls treated with six daily dosages of insulin increased their percentage of body fat significantly more than those treated with four daily injections (P < 0.05). CONCLUSIONS: In this prospective case-control study, we found that fat intake predicted gain in percentage of body fat in both adolescent girls with type 1 diabetes and healthy control girls. The number of daily insulin injections seems to influence the accumulation of body fat in girls with type 1 diabetes.

Absorptiometry, Photon↗

PubMed1992

[The effect of a milk-processing product on body nonspecific resistance].

Laboratory experiments in rats had shown that the standard ration of the structural food concentrate obtained from milk processing could increase the body resistance of animals by 20-30%. The estimation of the influence exerted by the concentrate was made on the basis of hypoxic and radiobiological models. The authors make a conclusion that application of this concentrate for prophylaxis has good prospects for the future.

Animals↗

PubMed2003

Studies on Merops orientalis Latham 1801 with special reference to its population in Mayiladuthurai, Tamil Nadu.

Role of habitat-structure and climatic factors in the population dynamics of the small green bee-eater Merops orientalis was evaluated in three habitats viz., agricultural lands, river banks and human habitations during 1991-1993. The river banks supported relatively high population of bee-eaters (157/Km2) followed by the agricultural lands (101/Km2) and human habitations (58/Km2). Bee-eater populations showed year-wise variations in river banks and human habitations having high values during 1992 (123/Km2) and 1993 (43/Km2) respectively. Agricultural lands showed a significantly low mean density in 1991 than other years. Seasonal variations in the bee-eater densities among the habitats were also recorded. Vegetation structure, food (insects) availability, climatic conditions and human disturbance were the casual factors for variations in bee-eater populations.

Animals↗

PubMed1982

Sensitivity to hymenoptera in adult males.

The authors studied the sera of 86 selected adult male office workers for IgE antibodies to yellow jacket and honey bee venoms and to environmental inhalants and foods. Structured histories provide information about the experiences of these men with the Hymenoptera and other immunological information. Three men (3%) gave a history of a local or general reaction to the Hymenoptera but no antibodies were detected. Ten men (12%) had IgE antibodies to yellow jacket or honey bee venoms but none gave a history of a reaction. Nine of these men were atopic. The authors speculate that IgE antibodies to the Hymenoptera in atopic adult males may be more common than is currently recognized.

Adult↗

PubMed1996

[The trend of proportion among inpatients with gout in 21 hospitals during the past 15 years].

We analyzed data gathered from 21 hospitals in our country from 1979 to 1993 on the total number of hospitalized patients with the number of gout patients. Results showed that the proportion of hospitalized gout patients in 21 hospitals has increased sharply during the past 15 years (Chi2 = 823.4, P < 0.001). The constituent ratio of hospitalized gout patients in 13 hospitals in southern China increased abruptly (Chi2 = 650.9, P < 0.001); while the constituent ratio in 8 hospitals in northern China increased to a lesser extent (Chi2 = 188.1, P < 0.001). A significant difference was noticed between southern and northern China (Chi2 = 45.8, P < 0.001). During the past 15 years, the proportion of hospitalized gout patients has been increasing rapidly, with greater extent in the south. This is probably related to the economic development which improves the standard of living and to the changes of food structure.

China↗