## 4 Discussion
### Reactive Oxygen and Nitrogen Species  
One of the novelties of this work reports the evaluation of baobab fruit pulp extracts against reactive oxygen species (ROS) and reactive nitrogen species (RNS). ROS and RNS play critical roles in the immune system. Moreover, oxidative stress is induced by an imbalance between the systemic synthesis of reactive pro-oxidant species and the biological system's ability to quickly neutralize or repair the ensuing damage. Antioxidant compounds obtained from food or dietary supplements can reduce the generation of reactive species at different stages of oxidative stress and through different pathways [21; 50]. Thus, traditional fruits, including baobab, might be acknowledged as significant healthy antioxidant sources [2; 9; 14]. The extracts' scavenging abilities against several ROS and RNS were assessed. O\({}_{2}\)\({}^{\bullet-}\) is the first reactive pro-oxidant specie produced because of the activity of multiple enzymes in the complex cascade of reactive species production. Once produced, O\({}_{2}\)\({}^{\bullet-}\) can be physiologically dismutated to H\({}_{2}\)O\({}_{2}\), either spontaneously under acidic conditions or through the action of the enzyme superoxide dismutase [51]. In turn, H\({}_{2}\)O\({}_{2}\) can form hydroxyl radicals (HO\({}^{\bullet}\)) through contact with transition metal ions. HO\({}^{\bullet}\) is the most reactive and oxidative ROS, and it can induce lipid peroxidation with polyunsaturated fatty acids, resulting in the production of ROO\({}^{\bullet}\). After a reaction with chloride ions and in the presence of myeloperoxidase, H\({}_{2}\)O\({}_{2}\) is also used to produce additional microbicide ROS, namely, HOCl [50,51]. A comprehensive review of the results obtained in this investigation revealed that, among the extracts examined, the hydroalcoholic extract has a higher scavenging effect against the assessed ROS and RNS (Table 3). In the O\({}_{2}\)\({}^{\bullet}\)--scavenging assay, Tiron was the most effective scavenger, whereas ascorbic acid was the least effective. Quercetin showed no activity in this assay up to the highest quantity tested (1000 \(\upmu\)g/mL). Furthermore, the ROO\({}^{\bullet}\)--scavenging capacity of baobab pulp fruit extracts was determined using the ORAC test. Nonetheless, none of the extracts demonstrated appreciable scavenging action for this ROS at the highest tested concentration (1 mg/mL). According to several studies, the cellular oxidative stress can be modulated by flavonoids by the scavenging of O\({}_{2}\)\({}^{\bullet-}\), neutralizing the effects of this ROS; through hydrogenation; or by complexing with oxidant species [21,50,52]. In terms of RNS-scavenging capacity, all of the extracts proved to be effective scavengers of both \({}^{\bullet}\)NO and ONOO\({}^{-}\). The hydroalcoholic extract was, once again, the most active of the extracts tested, with IC\({}_{50}\) values of 27 \(\pm\) 5, 19 \(\pm\) 1, and 17 \(\pm\) 1 \(\upmu\)g/mL for \({}^{\bullet}\)NO and ONOO\({}^{-}\) evaluated in the absence and presence of NaHCO\({}_{3}\), respectively. The inclusion of NaHCO\({}_{3}\) in the assays is crucial because, under physiological conditions, ONOO\({}^{-}\) rapidly reacts with CO\({}_{2}\) (in equilibrium with bicarbonate anion), resulting in the formation of the nitrosoperoxycarbonate anion (ONOOCO\({}_{2}\)\({}^{-}\)). The subsequent decomposition of ON  
by the location of the gathered baobab samples, as well as the extraction solvents and analytical procedures. For the first time in baobab fruit research, results were presented showing that the use of non-toxic green solvents allowed the production of extracts capable of scavenging ROS and RNS. Summarizing, the obtained results demonstrated that _A. digitata_ fruit pulp is rich in bioactive compounds that may be related to its biological activity, which is characterized by evident antioxidant properties, corroborating the nutritional value of this delicacy.