Folin-Ciocalteu Reaction Alternatives for Higher Polyphenol Quantitation in Colombian Passion Fruits
Table 2
Alternative F-C reacting conditions for TPC in Passifloras ( conditions representing significant differences and the best treatment based on ANOVA and post hoc Tukey’s HSD test considering ).
Reaction conditions
Compared variables
Observations
F-C (volume)
100 μL, 1.0 mL
Using microvolumes (100 and 200 μL led to higher variability in absorbance results and higher standard deviations).
Na2CO3 (volume)
200 μL, 2.0 mL
Na2CO3 (%)
1.5, 3.5, 7.0, 10, 20
Sodium carbonate concentration was determinant for the elimination of turbidity. The 3.5% assay avoided phenolate formation.
Time (min)
30, 90, 200
Reaction times at 30 and 200 minutes yielded no significant differences, and TPC values were higher at 90 minutes.
Light exposure
Yes/no
Exposure to light affected, at a higher level, reactions run in the micromilliliter level yielding higher variability.
Temperature (°C)
17, 36
Room temperature showed improved reaction results and higher TPC values.
