SPDS SET 2: FOL-01

Gabriel A Agbor (2014) Folin-Ciocalteau Reagent for Polyphenolic Assay 3:801

Table 2. Free Polyphenolic concentration (mg/g catechin equivalent) of herbs and spices as determined by single and dual reagent method.

Herbs and spices

Single Reagent Poly- phenol (μM)

Single reagent preci- sion (%)

Dual Reagent Poly- phenol

Dual reagent preci- sion (%)

P nigrum (leaves)

7.29

4.12

22.91 ±1.64 22.04 ±0.41 39.73 ±0.82 12.76 ±0.41 15.08 ±1.23 26.68 ±0.41 12.47 ±1.34 17.69 ±2.31 14.21 ±2.46 ±1.23 32.48 ±2.23 25.23 ±2.46 8.7

7.16

±0.30

P nigrun (black pep- per, seed)

7.14

1.12

1.86

±0.08 10.38 ±0.15

P umbellatum (leaves) H cannabinus (leaves)

1.45

2.06

5.44

1.47

3.21

±0.08

R. heudelotti (seeds) 5.86

3.92

8.16

±0.23

S zenkeri (seeds)

7.97

1

1.54

±0.08

S zenkeri (bark)

5.38

4.65

10.75

±0.25

A lepidophyllus (seeds) C mannii (seeds)

6.34

5.05

13.05

±0.32

5.7

7.89

17.31

±0.45

I gabonensis (seeds) 4.69

4.9

14.14

±0.23

T vulgaris (seeds)

9.05

2.54

6.87

±0.23

G africanum (seeds) 7.72

5.83

9.75

±0.45

P nigrum (white pep- per, seeds))

4.32

9.95

6.67

8.1

±0.43

±0.54

Figure. 2. Standard curve: Concentration of catechin against absorbance for the single reagent method

Average absorbance against concentration

0.8

0.6

0.4

y=0.007x-0.0324 R 2 =0.9971

0.2

0

Absorbance (750 nm)

0

100

50

200

Concentration of catechin statndard (uM)

a solution of 1mM. This is stable in the refrigerator at 4 o C for at least one month. Prepare standard curve by taking 0, 10, 20, 40, 50, 100 µl of the 1mM catechin solution to each of 6 micro cuvettes (10 to 100 µM in the cuvette).

Single reagent assay Standard Catechin Sample Preparation and Analysis. Weigh 2.9 mg of catechin powder in 10mL of methanol making

International Journal of Food Science, Nutrition and Dietetics, 2014 ©

4