The Food Commodities and Ingredients Group would like to congratulate Yannan Jin, Department of Food and Nutritional Sciences, University of Reading for being awarded first place in the ‘Antioxidants in Food – from Science to Shelf’, poster competition.
Ms Jin was born in China and began a four-year BSc Food Science course in the UK in 2002. After completing her second year study, Ms Jin went onto undertake a one-year industrial placement with GlaxoSmithKline under its Consumer Healthcare and Nutrition Sector from 2005 to 2006.
Since completing her undergraduate degree, Ms Jin began PhD research in Nutritional Sciences specialising in the impact of fruits and vegetables intake and particularly their antioxidants on cardiovascular health in humans, including flavonoids, vitamin C, uric acid, carotenoids and tocopherols.
Ms Jin has recently been involved in two projects, including a blackcurrant juice study, which examined the intake of flavonoid-rich juice on CVD risk factors and flavonoid bioavailability; as well as a FLAVURS study, which aimed to quantify and qualify the efficient portion size and types of fruits and vegetables intake on preventing CVD risk in humans.
Ms Jin’s abstract, below, highlights the research undertaken for her initial project, ‘Blackcurrant juice study in human subjects,’ sponsored by GSK:
Effect of acute consumption of blackcurrant juice on plasma and urine concentrations of phenolic acids and flavonoids and on antioxidant status in human subjects
Y.N. Jin, D. Alimbetov, M.H. Gordon and J.A. Lovegrove, Hugh Sinclair Unit of Human Nutrition, Department of Food and Nutritional Sciences, University of Reading
Emerging epidemiological evidence suggests that consumption of fruits and vegetables rich in flavonoids is inversely linked to the risk of CVD, but the exact mechanisms are unclear. The present study investigated the effects of acute consumption of a 20% blackcurrant juice drink on plasma and urine concentrations of anthocyanin metabolites and plasma antioxidant status in humans. In a randomized, double-blind, placebo-controlled cross-over design, 20 healthy human subjects (ages 30-70 y, 11 females 9 males) consumed 250 mL of the 20% blackcurrant juice drink or a placebo drink on two intervention visits with one-month washout.
Blood and urine samples were collected at baseline and periodically after juice intake for 8-hours, in addition to a 24-hour urine samples. Plasma vitamin C concentrations increased significantly from baseline after blackcurrant juice consumption compared to those of the control group throughout the study day (P=0.001), particularly at 60 – 90 minutes after consumption. Plasma insulin levels increased significantly after blackcurrant juice intake at 30 minutes (P<0.05) and remained higher than in the control samples throughout the study day (P=0.013), which was ascribed to the sugar content of the blackcurrant drink.
The plasma concentrations of phenolic acids that are known metabolites of flavonoids, namely benzoic acid, hippuric acid, salicylic acid and phenylacetic acid tended to increase at 30 and 180 minutes after blackcurrant juice intake, and a weak interaction was observed between juice treatment and time (P=0.099). The urinary hippuric acid and total phenolics also tended to show non-significant increases after juice consumption. Delphinidin and cyanidin derivatives were not detected in urine samples at quantifiable concentrations, although there was some evidence of traces present in some samples. There were no significant treatment effects on the oxidative stability of plasma assessed by the ORAC and FRAP values.
Plasma uric acid concentration was significantly correlated with the FRAP value of plasma at times of 0 - 480 minutes after drink consumption (P=0.000). Also the plasma uric acid concentrations at 150 - 180 minutes correlated significantly with the plasma ORAC values at 180 minutes in the test group (P<0.05), which is consistent with the important contribution of uric acid to antioxidant capacity. Overall, the effects of the 20% blackcurrant juice drink on plasma concentrations of flavonoid metabolites and plasma antioxidant status were not sufficiently large to be significant in the study.
Acknowledgement: The project was funded by GlaxoSmithKline