## 3 Results and Discussion
### Total Phenolic Content and Antiradical Activity by DPPH and ABTS Assays  
The TPC and radical scavenging activity, measured by DPPH and ABTS assays, were analysed to evaluate the functional attributes of MPP addition. The TPC is fundamental for assessing the presence of phenolic compounds, which are known for their beneficial effects, including antioxidant and anti-inflammatory properties, as well as their ability to protect against oxidative stress [46]. Additionally, the DPPH and ABTS assays allow for the determination of antioxidant capacity. The raw materials results are shown in Table 5.  
The results of the TPC analysis in MPP showed a significantly higher value of 276.93 mg GAE/g. Literature data report variable TPC values in mango peels; for instance, [PERSON] et al. [47] determined TPC values to be around 70 mg GAE/g (dry weight), while [PERSON] et al. [48] reported values around 112 mg GAE/g (dry weight). This variability can be attributed to several factors, including differences in mango varieties and preservation methods [47; 48]. Interestingly, our findings reveal a notably higher TPC, even in comparison with other fruits [49; 50]. Furthermore, previous studies have highlighted how mango peels contain a higher polyphenol content than other parts of the mango, including its pulp [51], indicating the potential of this by-product as a functional additive. MPP also showed substantial antiradical activity, with values of 70.26 mmol TEAC/100 g (DPPH assay) and 281.99 mmol TEAC/100 g (ABTS assay), highlighting the valuable functionality of this by-product. The TPC values obtained for the control bread (CTR) and mango-peel-powder-fortified bread samples (MPP-5, MPP-10) are reported in Table 6.  
Bread samples fortified with MPP showed very promising TPC values compared with control bread (CTR). Indeed, our results show that, in experimental bread samples (MPP-5, MPP-10), the addition of MPP increased the TPC, especially in those fortified at 10% (98.93 mg GAE/g). In a study by [PERSON] et al. [13], bread enriched with 5% MPP exhibited a TPC of 7.57 mg GAE/g. In contrast, our current study found that bread enriched with the same amount of MPP had a significantly higher TPC of 44.76 mg GAE/g, suggesting that experimental bread is a promising carrier for delivering antioxidant compounds. Additionally, in the evaluation of antiradical activity (Table 6), DPPH and ABTS values, expressed as mmol TEAC/100 g, were higher in all \begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Samples**} & **TPC** & **DPPH** & **ABTS** \\  & **(mg GAE/g DM)** & **(mmol TEAC/100 g DM)** & **(mmol TEAC/100 g DM)** \\ \hline Semolina & 5.02 \({}^{\text{a}}\) & 0.24 \({}^{\text{a}}\) & 0.44 \({}^{\text{a}}\) \\ MPP & 276.93 \({}^{\text{b}}\) & 70.26 \({}^{\text{b}}\) & 281.99 \({}^{\text{b}}\) \\ SEM & 35.25 & 9.05 & 0.07 \\ \(p\) value & 0.002 & \textless{}0.0001 & 0.0043 \\ \hline \hline \end{tabular} Results indicate mean values of 6 determinations (carried out in triplicate for 2 independent productions). Abbreviations: ITC, total phenolic content; mango peel powder (MPP); SEM, standard error of the mean. Letters that are different within the same column indicate significant difference (\(p\) < 0.05).  
\end{table} 
Table 5: Antioxidant and antiradical activity of semolina and mango peel powder. fortified bread samples compared with the control, according to percentage of fortification. In particular, bread fortified with 10% of MPP showed values of 29.46 and 116.62 mmol TEAC/100 g for DPPH and ABTS, respectively, compared with the control values of 1.02 and 0.16 mmol TEAC/100 g for DPPH and ABTS, respectively. Additionally, when compared with bread containing avocado waste powder [26], our study showed higher values for TPC, DPPH, and ABTS. The results from our analyses indicate that the antioxidant potential is improved by enriching bread with different percentages of MPP compared with the CTR bread.