In vitro scavenging capacity of annatto seed extracts against reactive oxygen and nitrogen species

Abstract

Bixa orellana L. (annatto), from Bixaceae family, is a native plant of tropical America, which accumulates several carotenoids (including bixin and norbixin), terpenoids, tocotrienols and flavonoids with potential antioxidant activity. In the present study, the in vitro scavenging capacity of annatto seed extracts against reactive oxygen species (ROS) and reactive nitrogen species (RNS) was evaluated and compared to the bixin standard. Annatto extracts were obtained using solvents with different polarities and their phenolic compounds and bixin levels were determined by high performance liquid chromatography coupled to diode array detector. All annatto extracts were able to scavenge all the reactive species tested at the low μg/mL range, with the exception of superoxide radical. The ethanol:ethyl acetate and ethyl acetate extracts of annatto seeds, which presented the highest levels of hypolaetin and bixin, respectively, were the extracts with the highest antioxidant capacity, although bixin standard presented the lowest IC(50) values.

Bioactive compounds and scavenging capacity of extracts from different parts ofVismia caulifloraagainst reactive oxygen and nitrogen species

“…In this study, all extracts of V. cauliflora were very efficient scavengers of NO, with low IC 50 values (varying from 0.9 to 2.2 mg/mL). The whole fruit extract exhibited the lower efficiency (3.6 ± 0.2 mg/mL) than other parts; nevertheless, its IC 50 value was similar to bixin (3 mg/mL), considered as a good scavenger of NO (Chisté et al, 2011). In relation to ONOO À , this RNS has been shown as a strong oxidizing and nitrating compound capable to oxidize a variety of biomolecules including lipids, proteins, carbohydrates, and DNA (Carr et al, 2000).…”

“…The H 2 O 2 -induced oxidation of lucigenin system was used to measure the scavenging capacity of V. cauliflora extracts and standards by a chemiluminescence methodology (Chisté et al, 2011) and the results are expressed as the inhibition, in percentage, of the H 2 O 2 -induced oxidation of lucigenin.…”

“…The NO-scavenging capacity of V. cauliflora extracts and standards was determined according to Chisté et al (2011). NO was generated by decomposition of NOC-5, and the NO À induced oxidation of non-fluorescent DAF-2 to the fluorescent triazolofluorescein (DAF-2T).…”

“…The ONOO À -scavenging capacity of each V. cauliflora extract and standards was determined by monitoring the ONOO À -induced oxidation of non-fluorescent DHR to the fluorescent rhodamine 123 (Chisté et al, 2011). In a parallel set of experiments, the assays were performed in the presence of 25 mM NaHCO 3 , in order to simulate the physiological CO 2 concentrations.…”

Correlation, by multivariate statistical analysis, between the scavenging capacity against reactive oxygen species and the bioactive compounds from frozen fruit pulps

“…On the other hand, carbohydrates, proteins, and amino acids are also components of the extracts and therefore can play a great hole in its scavenging capacity against H 2 O 2 since these compounds have been previously reported as efficient scavengers of ROS (PATTISON; DAVIES, 2006). For example, annatto seed extracts, which have both phenolic compounds (minor compounds) and carotenoids (major compounds) exhibited higher scavenging capacity against H 2 O 2 (IC 50 from 11 to 47 µg/mL) (CHISTÉ et al, 2011) than those of the 18 frozen fruit pulps analyzed in this study. Moreover, H 2 O 2 is rather inert at low concentrations, and its oxidation power is believed to be observed in combination with Fe(II) through Fenton reaction (HUANG; OU; PRIOR, 2005).…”