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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: 2010Has files: No

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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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    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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    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.
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    Effect of cinnamon (Cinnamomum Zeylanicum) supplementation on serum C-reactive protein concentrations: A meta-analysis and systematic review
    (Elsevier, 2018-12-07) Vallianou, Natalia; Tsang, Catherine; Taghizadeh, Mohsen; Davoodvandi, Amirhossein; Jafarnejad, Sadegh
    Objective: The effect of cinnamon (Cinnamomum Zeylanicum) on serum C-reactive protein (CRP), an acute phase protein commonly used as a marker of inflammation, is uncertain. Therefore, the objective of the present study was to conduct a systematic review and meta-analysis of published randomised controlled trials (RCTs) of cinnamon to determine the effect on levels of serum CRP, relative to controls. Design: Studies were identified by a search of electronic databases including PubMed, Cochrane Library, Google Scholar and Scopus before August 2018. Combined and stratified analyses were used. Weighted mean differences (WMD) and its 95% confidence interval were estimated for net change in serum CRP by using random-effects model. The heterogeneity of meta-analysis was assessed by χ2 and I2 test. Results: Six studies were identified, and data from 285 participants were included. Pooled analysis showed significant reductions in serum CRP (WMD: −0.81 mg/L, 95% CI: −1.36 to −0.26, p = 0.004), with significant heterogeneity between selected studies. Improvements in sub-group analysis were observed when baseline CRP levels were greater than 3 mg/dL, and in trials of >12 weeks duration. Doses <1500 mg/day and ≥1500 mg/day were effective in lowering serum CRP (WMD: −0.56 mg/dL, 95% CI: −1.01 to -0.10, p = 0.02 and WMD: −2.13 mg/dL, 95% CI: −4.08 to −0.19, p = 0.03), respectively, with significantly reduced heterogeneity in trials with lower doses of cinnamon <1500 mg/day (test for heterogeneity: P = 0.22 and I2 = 33%). No changes were found in controls. Conclusion: Cinnamon supplementation improves levels of serum CRP, particularly in chronic conditions, where basal CRP levels are raised. Further well-designed studies are warranted to confirm or not the above-mentioned findings.
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    Challenge your borders: Nutrition and Health
    (2019) Tsang, Catherine
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    A meta-analysis of the effect of chromium supplementation on anthropometric indices of subjects with overweight or obesity
    (Wiley, 2019-05-21) Tsang, Catherine; Taghizadeh, Mohsen; Aghabagheri, Elahe; Asemi, Zatollah; Jafarnejad, Sadegh
    The role of chromium as a weight loss agent remains questionable, and although previous meta-analyses findings have reported small reductions in body weight in individuals with overweight/obesity following chromium supplementation, there have been significant limitations with these findings. The objective of this meta-analysis was to evaluate the current evidence for the efficacy of oral chromium supplementation in individuals with overweight/obesity from randomized controlled trials. Studies were identified by a search of electronic databases from inception to November 2018 and combined and stratified analyses were used. Twenty-one trials from 19 studies were identified which met all inclusion criteria which were suitable for statistical pooling, and data from 1316 participants were included. Pooled analysis showed significant reductions in anthropometric indices associated with body composition; for weight loss (weighted mean difference [WMD]: −0.75 kg, 95% confidence interval [CI], −1.04, −0.45, P < 0.001), body mass index (WMD: −0.40, 95% CI, −0.66, −0.13, P = 0.003 and body fat percentage (WMD: −0.68%, 95% CI, −1.32, −0.03, P = 0.04) in individuals with overweight/obesity. No changes were detected in controls. Subgroup analysis showed significant improvements in weight loss and body fat percentage, particularly for study durations ≤12 weeks and doses ≤400 μg/d. Chromium supplementation was associated with some improvements in body composition in subjects with obesity/overweight. The effect size was medium and the clinical relevance of chromium as a weight loss aid remains uncertain. Further investigation from larger and well-designed randomized controlled studies, especially in patients with diabetes, is warranted.