## 2 Materials and Methods
### In Vitro Gastrointestinal Digestion  
The bioaccessibility of bioactive compounds and antioxidant capacity of Mexican plum powder, Mexican plum extract and microcapsules was performed according to the methodology by [PERSON] et al. [10] which simulates the digestion in mouth (oral phase), stomach (gastric phase) and small intestine (intestinal phase). Analyses of all phases were performed in triplicate.  
Digestion was started by mixing 5 g of the sample (microcapsules, Mexican plum powder or Mexican plum extract) with 2.5 mL of Simulated Salivary Fluid (SSF), followed by the addition of 0.5 mL of \(\alpha\)-amylase (1500 U/mL); 25 \(\mu\)L CaCl\({}_{2}\) (0.3 M) and 0.975 mL of distiller water (to obtain a suspension with a final volume of 10 mL). The suspension was adjusted to pH 7 and gently stirred for 2 min at 37 \({}^{\circ}\)C. In the gastric phase, 7.5 mL of Simulated Gastric Fluid (SGF) was mixed with the oral phase (10 mL), followed by the addition of 1.6 mL of bovine pepsin (25000 U/mL), 5 \(\mu\)L CaCl\({}_{2}\) (0.3 M), 0.2 mL of HCl (1 M) and 0.695 mL of distiller water (to obtain a suspension with a final volume of 20 mL). The suspension was adjusted to pH 2 with HCl (1 M) and gently stirred for 2 h at 37 \({}^{\circ}\)C. After 2 h, an aliquot of 10 mL was taken and immersed on ice for 10 min, then the pH was adjusted to 9 with NaOH (1 M) to stop the reaction. The aliquot was centrifuged at 1796\(\times\)_g_ (3400 rpm) for 10 min. The supernatant was used for the analysis of phenolics compounds, total anthocyanins, ascorbic acid, dehydrofacorbic acid and antioxidant capacity (ABTS, DPPH).  
For the small intestinal digestion phase, 5.5 mL of the SGF was mixed with 10 mL of Simulated Intestinal Fluid (SIF), followed by the addition of 2.5 mL parcarent (800 U/mL), 1.25 mL of bile salts (160 mM), 20 \(\mu\)L CaCl\({}_{2}\) (0.3 M), 75 \(\mu\)L NaOH (1 M) and 0.655 mL of distilled water (to obtain a suspension with a final volume of 20 mL). The suspension was adjusted to pH 7 and gently stirred for 2 h at 37 \({}^{\circ}\)C. After this time, the sample was immersed on ice for 10 min, then the pH was adjusted to 9 with NaOH (1 M) to inactivate the enzymes. The sample was centrifuged at 1796\(\times\)_g_ (3400 rpm) for 10 min. The supernatant was used for the analysis of phenolics compounds, total anthocyanins, ascorbic acid, dehydrofacorbic acid and antioxidant capacity (ABTS, DPPH).  
The release of phenolics compounds, total anthocyanins, ascorbic acid, dehydrofacorbic acid and antioxidant capacity during the in vitro digestion process was evaluated with the recovery index (%R) and bioavailability index (%B) calculated with Equations (4) and (5), respectively [32]:  
\[\%\mathrm{R}=\frac{\mathrm{A}}{\mathrm{C}}\times 100 \tag{4}\]  
\[\%\mathrm{B}=\frac{\mathrm{B}}{\mathrm{C}}\times 100 \tag{5}\]  
where A is the content of the compounds (phenolics, total anthocyanins, ascorbic acid, dehydrofacorbic acid or antioxidant capacity) released after gastric digestion, B is the content of the compounds (phenolics, total anthocyanins, ascorbic acid, dehydrofacorbic acid or antioxidant capacity) released after intestinal digestion and C is the content of the compounds (phenolics, total anthocyanins, ascorbic acid, dehydrofacorbic acid or antioxidant capacity) before digestion.