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three experimental models: DPPH, ABTS
and FRAP. The results for DPPH and ABTS
showed values ranging from 33.9 ± 9.7 to
324 ± 15.0 and 455.5 ± 7.8 to 17.3 mmol TE/g
of EPP, respectively (Table 7.4). The sam-
ples of C-T and B-R showed the highest val-
ues in both antioxidant assays, and the
extract with the lowest values was UN-T.
The highest value in the DPPH and ABTS
tests was for C-T and B-R extracts, respec-
tively, even higher than the standard (BHT).
It is worth mentioning that there is an appre-
ciable difference between the radical scav-
enging activity values shown by C-T and
C-R; this could be explained because,
although both samples were collected in the
same place, the method of collection
employed was different.
As in DPPH and ABTS tests, the best
values in the FRAP assay were shown by
C-T and B-R but in both cases were lower
than the standard (BHT). Again, the UN-T
extract showed the lowest value in FRAP
assay.
When we compared these results with
TPC, TFC and
1%
LA-2T had the highest scavenging activity
against the ABTS cation, followed by CH-2T.
Unfortunately, a FRAP analysis of the most
active samples was not done.
A second important factor to consider
is the method of collection. A comparison
between samples collected in the same
period (i.e. CH-1T and CH-1R) by the two
methods (scraping and plastic trap) clearly
show that the highest antioxidant activity
values are for the samples that were col-
lected by plastic trap.
These results are in line with the values
obtained in TPC. For this case, the sample
LA-2T that presented the highest DPPH,
ABTS and FRAP values also showed the
highest phenolic content.
Propolis from the Atlántico Department
In addition to the three antioxidant analyses
carried out with the samples of Antioquia,
we also analysed the propolis samples of
Atlántico with the ORAC assay. The results
obtained with these samples are outlined in
Table 7.6.
The propolis from Galapa was the most
active extract in the DPPH radical test
(190.41 mmol TE/g EEP), followed by Santo
Tomás (134.18 mmol TE/g EEP) and Juan de
Acosta (103.79 mmol TE/g EEP). The lowest
scavenging radical DPPH activity was shown
by Sabanalarga (65.14 mmol TE/g EEP).
A similar trend to that observed in the
DPPH analysis was shown in the discolora-
tion of the blue radical cation ABTS and
FRAP assays because, in both tests, the
propolis from Galapa was the most active
and the propolis from Sabanalarga the low-
est. None of the samples tested presented
higher antioxidant capacity values than the
standard.
In the ORAC analysis the highest val-
ues were shown by extracts from Santo
Tomás (2211.94 mmol Trolox/g propolis)
and Galapa (1964.80 mmol Trolox/g propo-
lis), respectively. Following the tendency,
the lowest value in the ORAC test was
Sabanalarga's sample (475.02 mmol Trolox/g
propolis).
Furthermore, extracts of propolis col-
lected in Galapa, Santo Tomás and Juan de
1
c
E
values, a positive corre-
lation can be appreciated. The samples, C-R
and B-T, that displayed the highest values
in the antioxidant activity assays, also
showed the highest TPC, TFC and
1%
1
c
E
val-
ues. The opposite can be observed in the
UN-T sample. Although more factors influ-
ence propolis antioxidant activity, the
results are consistent with previous studies
where a positive correlation between TPC
and TFC content with a significant antioxi-
dant activity is established (Gregoris and
Stevanato, 2010).
n o r t h
r e g i o n
.
The antioxidant capacity
analyses were carried out with DPPH, ABTS
and FRAP models. We want to emphasize
some results from Table 7.5. The best anti-
oxidant activity results in the three tests
were obtained for LA-2T, DM-2T and CH-2T
samples collected by trap in the second
period (August-November 2009). This sea-
son is recognized in the zone as a dry time.
The sample that showed the best value in
DPPH antioxidant assay was LA-2T (771.8 ±
16.8), even three times more than the sec-
ond one, CH-2T (243.7 ± 0.0). Similarly,
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