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Dietetics, Nutrition and Biological Sciences

Permanent URI for this collectionhttps://eresearch.qmu.ac.uk/handle/20.500.12289/23

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Start date: 2010End date: 2019

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Now showing 1 - 10 of 243
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    The effect of green-coffee-bean extract rich in chlorogenic acid on antioxidant status of healthy human volunteers
    (Cambridge University Press, 2010-01) Almoosawi, Suzana; Tsang, Catherine; Davidson, Isobel M; Fyfe, Lorna
    Several studies have linked consumption of green-coffee-bean extract (GCBE) rich in chlorogenic acid (CGA) with reduced blood pressure(Reference Watanabe, Arai and Mitsui1–Reference Ochiai, Jokura and Suzuki3). It is hypothesised that increased antioxidant activity could be one of the underlying mechanisms by which GCBE reduces blood pressure. To test this hypothesis a GCBE preparation rich in CGA was assessed by three extraction methods for antioxidant activity. In vivo antioxidant activity was also determined in a group of healthy volunteers. The phenolic content of GCBE, as determined by the Folin-Ciocalteu method, varied greatly between the ethanolic acidified water (0.2% (v/v) formic acid) and acetonitrile extract (acetonitrile–water containing 0.2% (v/v) formic acid; 50:50, v/v): 123 (sd 0.23), 131 (sd 0.66) and 211 (sd 0.51) mg gallic acid equivalents (GAE)/g extract respectively. Similar findings were observed with the Fe3+-reducing ability of plasma (FRAP) assay, wherein the acetonitrile extract exhibited a stronger Fe3+-reducing ability than the ethanolic extract (0.067 mmol/g extract v. 0.048 mmol/g extract). The 2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl (DPPH) radical-scavenging activity of the ethanolic extract of GCBE was 70.4% at 50 μm as compared with ascorbic acid (86.1% inhibition at 50 μm) and GAE (82.2% at 50 μm). To examine in vivo antioxidant properties of GCBE thirteen healthy volunteers (age 36 (sd 11) years, BMI 28 (sd 2.5) kg/m2) consumed 200 mg GCBE containing 90 mg CGA twice daily for 2 weeks. In vivo antioxidant activity was determined using the Folin-Ciocalteu method and FRAP. There was a significant correlation between urinary polyphenols excretion as determined by the Folin-Ciocalteu method and FRAP (0.664, P<0.0001). However no significant increase in urinary antioxidant activity was observed (total phenolics: 173.2 (sd 137.8) mg GAE/g creatinine v. 175.20 (sd 115.7) mg GAE/g creatinine, P>0.05; FRAP: 2.07 (sd 0.9) mmol Fe2+/g creatinine v. 1.56 (sd 0.7) mmol Fe2+/g creatinine, P>0.05). Systolic blood pressure decreased from 119 (sd 10.5) to 114 (sd 9.1) mmHg (P=0.05) following the 2-week treatment. In conclusion, green coffee bean extract has a high antioxidant activity. However, no changes in antioxidant activity are observed in urine. This finding is consistent with previous findings of poor antioxidant activity of hippuric acid, the main urinary metabolite of chlorogenic acid(Reference Olthof, Hollman and Buijsman4). Further research is required to identify the mechanism(s) of reduction in blood pressure. The antioxidant activity of plasma should also be determined.
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    PP431 ANTIOXIDANT POTENTIAL OF PAEDIATRIC TUBE FEEDS
    (Elsevier, 2010-09-29) Mckenzie, Jane M.; Tsang, Catherine
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    Effect of a tomato-rich diet on markers of cardiovascular disease risk in moderately overweight, disease-free, middle-aged adults: a randomized controlled trial
    (Elsevier, 2012-04-04) Thies, Frank; Masson, Lindsey F; Rudd, Amelia; Vaughan, Nicholas; Tsang, Catherine; Brittenden, Julie; Simpson, William G; Duthie, Susan; Horgan, Graham W; Duthie, Garry
    Background: Cardiovascular disease (CVD) is a major cause of mortality in the United Kingdom. Epidemiologic studies suggest that consumption of tomato-based foods may lower CVD risk. Such potential benefits have been ascribed in part to high concentrations of lycopene in the tomatoes. However, these findings have not yet been validated by comprehensive intervention trials. Objective: The aim of this study was to conduct a single-blind, randomized controlled intervention trial with healthy middle-aged volunteers to assess whether the consumption of tomato-based foods affects recognized biomarkers of CVD risk. Design: After a 4-wk run-in period with a low-tomato diet, 225 volunteers (94 men and 131 women) aged 40–65 y were randomly assigned into 1 of 3 dietary intervention groups and asked to consume a control diet (low in tomato-based foods), a high-tomato-based diet, or a control diet supplemented with lycopene capsules (10 mg/d) for 12 wk. Blood samples were collected at baseline, at 6 wk, and after the intervention and were analyzed for carotenoid and lipid profiles and inflammatory markers. Blood pressure, weight, and arterial stiffness were also measured. Dietary intake was also determined during the intervention. Results: None of the systemic markers (inflammatory markers, markers of insulin resistance and sensitivity) changed significantly after the dietary intervention. Moreover, lipid concentrations and arterial stiffness were also unaffected by the interventions. Conclusion: These data indicate that a relatively high daily consumption of tomato-based products (equivalent to 32–50 mg lycopene/d) or lycopene supplements (10 mg/d) is ineffective at reducing conventional CVD risk markers in moderately overweight, healthy, middle-aged individuals. This trial was registered at isrctn.org as ISRCTN34203810.
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    Bioavailability and Urinary Excretion of Phenolic-Derived Metabolites after Acute Consumption of Purple Majesty Potato in Humans
    (E-Cronicon, 2015-03-18) Tsang, Catherine; Smail, Nacer F.; McDougall, Gordon J.; Almoosawi, Suzana; Al-Dujaili, Emad A. S.
    A novel purple potato variety, Purple Majesty (PM) contains an abundance of phenolic compounds, especially anthocyanins. The aim of this study was to assess the bioavailability of phenolic compounds in plasma measured as total polyphenols and urinary excretion of phenolic-derived metabolites after acute consumption of cooked PM. Five healthy male subjects (27-60 years; mean BMI: 26.7 ± 4.1) participated in a bioavailability study. Blood and urine were sampled at baseline and following consumption of 400 g cooked PM at 1h, 2h, 4h and 24h. A peak plasma antioxidant capacity was reached 1-2 hours post-consumption (from 1044 ± 281 µmol/L Fe(II) at baseline and increased to 1257 ± 180 after 1 hour (p = 0.045) and 1112 ± 251 µmol/L Fe(II) after 2 hours (borderline significance of p = 0.06). Total phenols level in plasma was reached after 2 hours (from 342.4 ± 28.3 at baseline to 368.4 ± 25 mg/L GAE). Liquid chromatography mass spectrometric (LC-MS) analysis was used to track the levels of anthocyanin-like derivatives and metabolites in the urine of volunteers after intake of the cooked Purple Majesty potatoes. No anthocyanin derivatives were detected in urine by liquid chromatography mass spectrometry indicating levels were < 2 nM. The majority of peaks that increased after intake were putatively identified as sulphated phenolic metabolites. Phenolic glucuronides were identified but other peaks remain unidentified. Hippuric acid was identified as a major phenolic derivative. Hydroxy benzoic derivatives, characteristic of intake of anthocyanins, were not detected in urine, however metabolites expected from the B-ring of petunidin (i.e. methyl gallic acid) may have been obscured by other peaks. Some metabolites could have arisen through metabolism of chlorogenic acid, which is present at ~ equivalent amounts to anthocyanins in cooked PM. In conclusion, acute consumption of PM resulted in an increase in excretion of urinary phenolic-derived metabolites. Identifying these unknown phenolic derivatives warrants further investigation.
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    Encapsulation of ascorbic acid promotes the reduction of Maillard reaction products in UHT milk
    (Royal Society of Chemistry, 2016-05-17) Troise, Antonio Dario; Vitiello, Daniele; Tsang, Catherine; Fiore, Alberto
    The presence of amino groups and carbonyls renders fortified milk with ascorbic acid particularly susceptible to the reduction of available lysine and to the formation of Maillard reaction products (MRPs), as Nε-(carboxyethyl)-L-lysine (CEL), Nε-(carboxymethyl)-L-lysine (CML), Amadori products (APs) and off-flavors. A novel approach was proposed to control the Maillard reaction (MR) in fortified milk: ascorbic acid was encapsulated in a lipid coating and the effects were tested after a lab scale UHT treatment. Encapsulation promoted a delayed release of ascorbic acid and a reduction in the formation of MRPs. Total lysine increased up to 45% in milk with encapsulated ascorbic acid, while reductions in CML, CEL and furosine ranged from 10% to 53% compared with control samples. The effects were also investigated towards the formation of amide-AGEs (advanced glycation end products) by high resolution mass spectrometry (HRMS) revealing that several mechanisms coincide with the MR in the presence of ascorbic acid.
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    Consumption of Pomegranate Juice Attenuates Exercise - Induced Oxidative Stress, Blood Pressure and Urinary Cortisol/Cortisone Ratio in Human Adults
    (E-Cronicon, 2016-08-23) Al-Dujaili, Emad A. S.; Good, Gillian; Tsang, Catherine
    Background: Oxidative stress is exacerbated in overweight and obese individuals after acute exercise compared with their nonobese counterparts. Antioxidants supplementation of the diet may be one intervention to reduce exercise-induced oxidative stress in this vulnerable population. The aim of this study was to investigate whether polyphenol-rich pomegranate juice attenuates postexercise oxidative stress and contributors to oxidative stress (glucocorticoids) and blood pressure in healthy overweight subjects. Methods: Males and females participated in a randomized placebo controlled parallel pilot-study (mean BMI: 26.7 ± 6.6 kg/m2 ). Two groups of (n = 12) participants received either pomegranate pure juice (500 mL/day containing total polyphenols of 1685 mg GAE/L) or placebo (water matched for total energy) and all participants completed two standardized 30 min treadmill tests (50% Wmax) at baseline and after one week of the intervention. Results: Exercise induced lipid peroxidation (MDA) was lower following pomegranate juice consumption compared with placebo (31.2 ± 10.6 to 26.5 ± 9.8 MDA µmole/day) after 1 week (P = 0.035). Urinary free cortisol was reduced from 179.4 ± 53.2 to 125.6 ± 43.5 nmole/24h which was significant (p = 0.042). In addition, there was a statistically significant increase in urinary free cortisone: from 112.2 ± 40.4 to 187.6 ± 90.2 nmole/24 h (p = 0.045), and a significant decrease in the urinary free cortisol/cortisone ratio (p=0.009) from 1.6 ± 1.1 to 0.67 ± 0.55 following one week of pomegranate juice intake. Pomegranate juice consumption was also found to decrease systolic blood pressure pre-exercise (136.7 ± 11.7 to 131.8 ± 8.8 mmHg (p = 0.007), and post-exercise from 158.8 ± 15.8 to 148.1 ± 12.3 mmHg (p < 0.01) and diastolic blood pressure (86.3 ± 10.6 to 82.5 ± 6.8 mmHg (p = 0.04) and 103.1 ±12.5 to 93.9 ± 11.5 mmHg (p = 0.001), pre and post exercise, respectively. Correlation results between the change in Cortisol/cortisone ratio with the effect on blood pressure showed a negative significant association post pomegranate juice intake (p = 0.028 for systolic and p = 0,008 for diastolic BP). There were no changes in lipid peroxidation or blood pressure following placebo treatment. Conclusions: These findings suggest that pomegranate juice consumption prior to an acute bout of moderate intensity exercise can alleviate blood pressure and exercise-induced stress in the overweight and obese population.
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    Functional Foods and Lifestyle Approaches for Diabetes Prevention and Management
    (MDPI, 2017-12-01) Alkhatib, Ahmad; Tsang, Catherine; Tiss, Ali; Bahorun, Theeshan; Arefanian, Hossein; Barake, Roula; Khadir, Abdelkrim; Tuomilehto, Jaakko
    Functional foods contain biologically active ingredients associated with physiological health benefits for preventing and managing chronic diseases, such as type 2 diabetes mellitus (T2DM). A regular consumption of functional foods may be associated with enhanced anti-oxidant, anti-inflammatory, insulin sensitivity, and anti-cholesterol functions, which are considered integral to prevent and manage T2DM. Components of the Mediterranean diet (MD)—such as fruits, vegetables, oily fish, olive oil, and tree nuts—serve as a model for functional foods based on their natural contents of nutraceuticals, including polyphenols, terpenoids, flavonoids, alkaloids, sterols, pigments, and unsaturated fatty acids. Polyphenols within MD and polyphenol-rich herbs—such as coffee, green tea, black tea, and yerba maté—have shown clinically-meaningful benefits on metabolic and microvascular activities, cholesterol and fasting glucose lowering, and anti-inflammation and anti-oxidation in high-risk and T2DM patients. However, combining exercise with functional food consumption can trigger and augment several metabolic and cardiovascular protective benefits, but it is under-investigated in people with T2DM and bariatric surgery patients. Detecting functional food benefits can now rely on an “omics” biological profiling of individuals’ molecular, genetics, transcriptomics, proteomics, and metabolomics, but is under-investigated in multi-component interventions. A personalized approach for preventing and managing T2DM should consider biological and behavioral models, and embed nutrition education as part of lifestyle diabetes prevention studies. Functional foods may provide additional benefits in such an approach.
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    Anthocyanin-rich Potato Improves Cardiovascular Risk Factors in Healthy Human Adults
    (2017) Tsang, Catherine; Almoosawi, S; Smail, Nacer Foudil; Al-Dujaili, Emad
    Arterial stiffness is an emerging risk factor for cardiovascular disease (CVD), and dietary polyphenols, particularly anthocyanins, may play an important role in mediating vascular tone. The present single-blind randomised cross-over placebo controlled study investigated the effect of consumption of an anthocyanin-rich potato, Purple Majesty (PM) in 14 healthy male and female adults. Participants consumed 200 g of cooked PM containing 114 mg anthocyanins, or placebo (Osprey) with negligible anthocyanin content for 14 days, separated by a 1-week washout period. Non-invasive assessment of vascular tone (arterial stiffness) by pulse wave velocity (PWV) was determined in addition to systolic (SBP) and diastolic blood pressure (DBP), high density lipoproteins (HDL), low-density lipoproteins (LDL), triglycerides, glucose, insulin resistance (HOMA-IR) and c-reactive protein (CRP). Arterial stiffness was significantly reduced (p=0.001) following PM consumption. There were no significant changes with any other clinical parameter measured, and no changes were observed following placebo. PM contained higher levels of total phenolics, total anthocyanins and antioxidant capacity and daily consumption of PM over 14 days was well tolerated by participants. The findings from this study suggest improved vascular tone following daily consumption of PM and inclusion in the diet could provide a rich and valuable source of anthocyanins.
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    A meta-analysis of cumin (Cuminum cyminim L.) consumption on metabolic and anthropometric indices in overweight and type 2 diabetics
    (Elsevier, 2018-03-23) Jafarnejad, Sadegh; Tsang, Catherine; Taghizadeh, Mohsen; Asemi, Zatollah; Keshavarz, Seyed Ali
    Objective To conduct a systematic review, including meta-analysis, of published randomised controlled trials (RCTs) of cumin to determine the effect on anthropometric and metabolic indices in overweight and/or type 2 diabetics, relative to controls. Methods Studies were identified by a search of electronic databases before December 2017. Combined and stratified analyses were used. Results Seven trials were identified, and data from 412 subjects were included. Pooled analysis showed improvements in bodyweight, body mass index (BMI) and fasting blood glucose (FBG) by −1.74 kg, −0.67 kg/m2 and −17.82 mg/dL respectively. Significant findings were also observed in triglycerides (TG) [WMD: −21.23 (95% CI: −37.64 to −4.82; P < 0.001, I2 = 92%)] and HDL-c (high-density lipoprotein cholesterol) [WMD: 4.16 (95%CI: 3.30, 5.01; P < 0.001, I2 = 82%)] following cumin intake. No changes were found in controls. Conclusions Cumin improves anthropometric and metabolic indices in overweight and/or type 2 diabetic subjects. The changes were related to the clinical condition and quality assessment.