Figure 1: Extracted ion chromatograms of flavonoids in the extract of Venice tea
Figure 2: The kinetic curves of scavenged DPPH by the extracts of Citrus and Saga teas
Commercial name
Composition* (as per label)
Citrus

Black tea, citrus aroma (17.5%), peels of lemon (1.4%;), lime (1.4%), grapefruit (1.4%) and orange (1.4%)
Earl Grey

Black tea (89.3%), natural aroma (10.2%), marigold petals (0.3%), jasmine petals (0.2%)
Puerh pineapple
Tea from Yunnan province, pineapple (2.8 %)
Kashmir Valley

Black tea (83.2%), natural aroma (8.7%), cinnamon (5.8%), rose petals (2.3%)
Hyley`s
Premium black tea from Sri Lanka
Dilmah
Premium black tea from Sri Lanka
Saga
Premium black tea
Venice
Premium black tea from Ceylon
Table 1:Composition of the analyzed teas
Tea
Quercetin
Rhamnetin
Luteolin
Hesperidin
Naringin

Rutin

Citrus
0.038 ± 0.002
< LOD
0.006 ± 0.0002
0.69 ± 0.043
3.51 ± 0.099

8.59 ± 0.38

Earl Grey
0.097 ± 0.003
0.003 ± 0.0001
< LOD**
< LOD
0.004 ± 0.0001
12.8 ± 0.31

Puerh pineapple
0.39 ± 0.019
0.003 ± 0.0001
0.004 ± 0.0001
< LOD
< LOD

6.30 ± 0.29

Kashmir Valley
0.116 ± 0.004
0.011 ± 0.0005
0.015 ± 0.001
< LOD
0.009 ± 0.0003
10.8 ± 0.40
Hyley`s
0.065 ± 0.009
< LOD
< LOD
< LOD
< LOD
25.7 ± 0.072
Dilmah
0.035 ± 0.009
< LOD
< LOD
< LOD
< LOD
13.5 ± 0.34
Saga
< LOD
0.009 ± 0.001
< LOD
< LOD
< LOD
13.4 ± 0.41
Venice
0.034 ± 0.008
0.012 ± 0.0005
< LOD
0.025 ± 0.005
< LOD
25.1± 0.69
*Mean ± SD (n=3), expressed in mg/L; **LOD – limit of detection
Table 2: Content* of selected flavonoids in studied tea infusions
Tea

FC (mg GA/L)

DPPH (mmol TR/L)

Citrus
345 ± 12.9
0.35 ± 0.01
Earl Grey
701 ± 28.1
0.43 ± 0.02
Puerh pineapple
507 ± 14.0
0.39 ± 0.02
Kashmir Valley
546 ± 19.7
0.44 ± 0.03
Hyley`s
831 ± 37.1
0.55 ± 0.03
Dilmah
1119 ± 40.7
0.56 ± 0.02
Saga
830 ± 33.4
0.87 ± 0.04
Venice
1147 ± 38.7
0.56 ± 0.03
Mean ± SD (n=3)
Table 3: Antioxidant activity of tea extracts evaluated by FC and DPPH assays