ChemicalCharacterization,Antioxidant, andAntihyperglycemic Capacity of Ferulated Arabinoxylan Extracted from “Chicha de Jora” Bagasse: An Ancestral Fermented Beverage from Zea mays L

Department of Pharmacology, Bromatology and Toxicology, Faculty of Pharmacy and Biochemistry, Universidad Nacional Mayor de San Marcos, Jr. Puno 1002, Lima 1002, Peru Institute for Research in Pharmaceutical Sciences and Natural Resources, Faculty of Pharmacy and Biochemistry, Universidad Nacional Mayor de San Marcos, Jr. Puno 1002, Lima 15001, Peru Department of Pharmaceutical Chemistry, Faculty of Pharmacy and Biochemistry, Universidad Nacional San Luis Gonzaga, Ica, Peru Department of Pharmaceutical Sciences, Faculty of Pharmacy and Biochemistry, Universidad Nacional San Luis Gonzaga, Ica, Peru Department of Surgical Clinical Sciences, Faculty of Human Medicine, Universidad Nacional San Luis Gonzaga, Ica, Peru Department of Basic Sciences, Faculty of Human Medicine, Universidad Nacional San Luis Gonzaga, Ica, Peru Department of Chemistry Sciences, Faculty of Pharmacy and Biochemistry, Universidad Nacional San Luis Gonzaga, Ica, Peru Department of Clinical Laboratory Sciences, Faculty of Applied Medical Sciences, Najran University, Najran 61441, Saudi Arabia Division of Genome Sciences and Cancer, 5e John Curtin School of Medical Research, and 5e Shine-Dalgarno Centre for RNA Innovation, 5e Australian National University, Canberra 2601, Australian Capital Territory, Australia


Introduction
Chicha de jora (CJ) is a traditional Peruvian beverage with low alcohol content (1-3%) similar to beer, that is produced by fermentation of the germinated corn (Zea mays).
is beverage is produced with indigenous technology in places called "chicherias" [1], and the general steps for its preparation are shown in Figure 1. Its preparation generates a byproduct called bagasse which has mainly residues of corn husk constituting polysaccharides such as cellulose, hemicellulose, and lignin. e most representative hemicellulose of the bagasse is the ferulated arabinoxylan (FAX) which has potential application in the food, pharmaceutical, and cosmetics industry [2]. FAX chemically consists in a linear chain of D-xyloses linked by β-(1 ⟶ 4) glycosidic bonds, with substituents of D-arabinose by α-(1 ⟶ 3) or α-(1 ⟶ 2) glycosidic linkages, or both; some residues of D-arabinose have substituents of ferulic acid esterified in C-5 [3].
FAX has biological properties reported in the scientific literature, such as antioxidant, antidiabetic, anticoagulant, antiinflammatory, antimicrobial, immunoregulatory, and anticancer capacity [4]. Si et al. [5] extracted FAX from corn bran and evidenced a proportional relation between the presence of phenolic compounds linked to the polysaccharide and its antioxidant capacity. e polysaccharide is mainly esterified with ferulic acid but has been reported the presence in low proportion of other phenolic compounds such as p-coumaric and cinnamic acid [6]. Other factors including molecular weight, degree of polymerization, and ratio of arabinose and xylose (Ara/Xil) of the polysaccharide are responsible for its antioxidant capacity [7]. Additionally, Kamboj and Rana [8] showed that the antioxidant potential of the FAX isolated from corn bran is higher than polysaccharides such as guar gum, sulfated guar gum, and xanthan oligosaccharide. e FAX has the ability to inhibit the enzymatic activity of the sucrase and maltase in vitro, and it can also inhibit transporters of glucose-independent sodium 2 (GLUT2) in oocytes [9]. Huang et al. [10] investigated the antidiabetic capacity in vivo of ferulated oligosaccharides from corn bran in male rats with diabetes induced by streptozotocin (STZ), concluding that a dose of 600 mg/kg/day reduces significantly glucose, insulin, and LDL levels and increases HDL levels. Similarly, Nie et al. [11] reported that the FAX extracted from Plantago asiatica improves the metabolism of carbohydrates, lipids, and amino acids in rats with diabetes induced by STZ and a high-fat diet.
However, to date, the use of this byproduct has not been considered because there is no report in the scientific literature that supports its potential benefits. In the present study, FAX from bagasse of the CJ is extracted by alkaline hydrogen peroxide. e antioxidant and antihyperglycemic capacity in vitro is also examined.

Materials.
Bagasse of chicha de jora (traditionally called in Peru "sutuchi") was kindly provided by Misky S. A. C. (Cusco, Peru). It was washed 4 times with tap water, dried at 400°C for 48 h, and milled to a 20-mesh particle size.

Extraction of Ferulated Arabinoxylan.
e sample (100 g) was deoiled with n-hexane (700 mL) under 300 rpm for 2 h at 50°C [12]. en, 75 g was treated with thermostable α-amylase (4.5 mL of enzyme/100 g of sample). e pH was adjusted to 6.5 with 50% NaOH and then stirred between 85 and 90°C under 300 rpm for 2.5 h in H 2 O (750 mL). e fiber was washed twice with hot water and once with 96% ethanol to remove maltodextrin. It was dried at 50°C for 24 h [13].
e polysaccharides were extracted based on the work of Kamboj and Rana [8]. e deoiled and destarched sample (50 g) was added to 500 mL of H 2 O with 4 g of NaOH (2 mEq of alkali/ gram of fiber in the medium), and it was boiled for 1 h. Once cooled, it was centrifuged at 6000 ×g for 20 min at 25°C, and the supernatant was recovered by decantation. en, 17 mL of 30% H2O2 was added to the decanted fraction, and the pH was adjusted to 11.5 with 50% NaOH and stirred at room temperature for 2 h. After the pH was adjusted between 4 and 4.5 adding concentrated HCl to precipitate hemicellulose A, which was separated by centrifugation at 7100 ×g for 20 min at 25°C. Two volumes of 96% ethanol were added to the supernatant to precipitate the main FAX fraction, hemicellulose B. e FAX was allowed to settle as a white flocculent precipitate in cold, and it was removed by vacuum filtration with 96% ethanol. And then, it was dialyzed for 48 h in tap water and 48 h in distilled water on a dialysis membrane with a molecular weight cutoff (MWCO) of 3.5 kDa. e dialyzed sample was dried at 50°C for 48 h.

Physicochemical Characterization
e powdered sample was dissolved using different solvents (water, methanol, ethanol, ethyl acetate, acetone, and chloroform) according to monograph <5.11> of the European Pharmacopoeia 10.0 [14]. e solubility at different temperatures was carried out according to Kong et al.'s study [15], and the sample (100 mg) was mixed with 50

Total Ash.
e quantification of total ash was developed using the gravimetric method [16].

Protein Content.
e Kjeldahl method was used to quantify the protein content [16].

Micromeritic Analysis
(1) Angle of Repose. It was carried out following the funnel flow method indicated in the monograph <1174> of the USP 41 [18]. Initially, the tip of the funnel was kept 2 cm away from the surface. 10 g was allowed to flow freely over the funnel until a symmetrical cone was formed reaching the tip of the funnel. e height (h) and base radius (r) of the formed cone were measured and substituted into equation (1), where θ is the angle of repose.
(2) Bulk Density and Compacted Density. Initially, 10 g of sample was carefully added in a 50 mL graduated cylinder, and the volume occupied by the sample (V b , mL) was measured. en, it was mechanically tapped on a flat surface, and the volume was read after 500 taps when a constant volume (V c , mL) was evidenced [19]. Equations (2) and (3) allowed to obtain the respective calculations.
where ρ b is bulk density (g/mL), ρ c is compacted density (g/mL), and W is the sample mass (G).
where ρ b is the apparent density and ρ c is the compacted density.

2.3.7.
Viscosity. e flow time of different solutions of the sample (0.1, 0.4 and 0.8%, w/v) was measured at 30°C using an Ostwald viscometer [21]. e relative viscosity (ηrel) of the sample against distilled water was calculated, and formula (6) allowed the calculation of the specific viscosity (ηsp). e apparent intrinsic viscosity (ηint, dL/g) was determined using the Morris equation (7), where c is the FAX concentration:

Drying (2-3 h) Germination
Pre-treatment Fermentation Figure 1: General steps for the preparation of "chicha de jora." e bagasse is a by-product generated before the fermentation.

Identification of Monosaccharides by in-Layer Chromatography (TLC).
e sample (25 mg) was treated with 2 mL of 2 M trifluoroacetic acid (TFA) at 100°C for 2.5 h. e stationary phase was TLC Silica gel 60 F254 (Merck, Germany), and the mobile phase was chloroform, acetic acid, and water (3 : 3.5 : 0.5). After elution, it was revealed by spraying a mixture of diphenylamine (1 g) and aniline (1 mL) in acetone (100 mL), and before use was added 85% orthophosphoric acid (10 mL). e plate was dried at 100°C for 10 min.

Mass Spectrometry Parameters.
A full scan experiment combined with a fragmentation experiment (MS/MS) was performed for both modes of electrospray ionization (ESI + and −). e parameters of the ESI source are described as follows: spray voltage, 3.6 kV (−); sheath gas flow rate, 50 (arbitrary values); auxiliary gas flow rate, 10 (arbitrary values); tube lens voltage, 50 V; probe heater temperature, 400°C; capillary temperature, 300°C:  Table 1.

Analysis by UV-Vis Spectroscopy.
e sample (0.5%, w/ v) was placed in quartz cuvettes to scan the spectrum between 250 and 500 nm with a GenesysTM UV/Vis spectrophotometer ( ermo Fisher Scientific, San Jose, USA).

DPPH• Assay.
e DPPH• assay was determined by the method adopted by Marquez-Escalante and Carvajal-Millan [23] which avoids the precipitation of the sample. Initially, 50 mL of DPPH• 45 μM was prepared with methanol : water (60 : 40). Once dissolved, it was filtered through Whatman No. 1 paper and used after 1 h. en, 400 µL of sample (0.5-10 mg/mL) was mixed with 350 µL of methanol, and 750 µL of DPPH• was added. e curve of inhibition was made with different concentrations of Trolox (0.001-0.002 mg/mL). e absorbance was measured at 515 nm after 30 min of incubation in the dark. e % inhibition of the DPPH• radical was determined by the following equation: where A control is the absorbance of the control and A sample is the absorbance of the sample or standard.

ABTS•+ Assay.
Initially, 1.7 mL of 7 mM ABTS•+ (diluted to an absorbance of 0.7 ± 0.02 at 734 nm) were added to 100 µL of different concentrations of sample (0.1-10 mg/mL) and then left at rest for 7 min at room temperature, and the absorbance was measured at 734 nm. An inhibition curve of the Trolox was prepared using concentrations between 0.003 and 0.1 mg/mL [24]. e % inhibition of the ABTS•+ radical was determined using the following equation: where A control is the absorbance of the control and A sample is the absorbance of the sample or standard.

Determination of In Vitro Antihyperglycemic Capacity
2.11.1. Glucose Adsorption Capacity (GAC). CAG was determined using the method of Dong et al. [26]. In brief, 0.5 g of the sample was mixed with 50 mL of different concentrations of anhydrous glucose (10-200 mmol.L −1 ) and incubated at 37°C for 6 h. After centrifugation at 4500 ×g for 20 min at 25°C, the amount of adsorbed glucose was estimated quantifying the concentration of glucose in the supernatant using the glucose oxidase enzyme kit. CAG was expressed as mmol of glucose adsorbed per gram of sample (mmol/g) and was calculated according to the following equation: where C i and C f are the glucose content before and after of the absorption and W m is the weight of the sample.

Glucose Diffusion Inhibition
Capacity. e sample (2 mL) at different concentrations (1, 10, and 25 mg/mL) were placed in SnakeSkin ™ Dialysis Tubing of 3.5 kD MWCO ( ermo Fisher Scientific, San Jose, USA). en, 2 mL of glucose 0.25 M was added. e negative and positive controls were distilled water and acarbose, respectively. e dialysis tubing was sealed and then introduced in a beaker with NaCl 0.15 M (80 mL) and water (20 mL), and it was stirred at 150 rpm and 37°C. After 1 mL of the sample and controls were taken every 30 min for 180 min, glucose was quantified with a glucose oxidase enzyme kit at 505 nm. It was expressed in µg/mL [27].

α-Amylase Inhibition Capacity.
e test was carried out as reported previously by Inocente Camones et al. [28]. In brief, 125 µL of FAX or acarbose at different concentrations (0.1-5 mg/mL) were preincubated at 25°C for 10 min with 125 µL of α-amylase 13 U/mL (dissolved in sodium phosphate buffer 0.02 mol/L at pH 6.9). After preincubating, 125 µL of 1% soluble starch was added. en, 250 µL of 96 mM 3,5-dinitrosalicylic acid was added. e reaction was stopped by boiling the tubes for 15 min. ey were cooled at room temperature and dissolved with distilled water (3 mL) to finally read the absorbance at 540 nm. e % inhibition was calculated using the following equation: where A 1 , A 2 , A 3 , and A 4 are defined as the absorbance of the sample (with enzyme), absorbance of the sample blank (without enzyme), absorbance of the control with 100% activity (alone enzyme and solvent), and absorbance of the control blank with 0% activity (no enzyme), respectively.

Statistical
Analysis. e data was presented as mean-± standard deviation (SD) for three replicates. Two-way analysis of variance (ANOVA) with Turkey's post hoc test was used to make comparisons between treatments using the statistical program GraphPad Prism 6.0. Values of p < 0.05 were considered statistically significant.

Extraction of Ferulated Arabinoxylan.
e yield of the chemical extraction was 19.87 ± 4.56% (see Figure 2(c)), similar to the yield previously reported for the FAX of the corn pericarp (18%) [29]. A slightly higher yield (38%) was determined by Kamboj and Rana [8]. On the other hand, Buksa et al. [30] reported a yield of 1.7% and 3.2% for the polysaccharide from wheat and rye, respectively, in both cases extracted by the aqueous method. FAX is not efficiently extracted using water as extraction solvent. Alkaline conditions allow the breaking of ester bonds and hydrogen bonds within the cell wall [31]. Alkaline solutions with H 2 O 2 react rapidly with lignin to form water-soluble oxidized products of low molecular weight, which causes the rupture in the union of lignin and FAX [32].

Physicochemical Characterization
3.2.1. Solubility. FAX was soluble in water; very slightly soluble in ethyl acetate; and insoluble in methanol, ethanol, acetone, and chloroform. ese results were similar to those previously reported by Höije et al. [33]. e aqueous solubility is due to the high presence of hydroxyl groups (OH − ) in the polysaccharide chain and therefore to its greater capacity to form hydrogen bonds [34]. In addition, the polysaccharide could have an amphiphilic nature in which the nonpolar region could be represented by the rings of the monosaccharide [35]. Figure 2(d) Journal of Food Quality 5 shows that the highest dissolution time of 79.33 ± 7.02 min occurred at 25°C; however, at 100°C, the time was reduced to 8.00 ± 3.61 min.

Moisture
Content. e moisture content was 8.00 ± 1.77% (see Table 2), lower than the yield of 12.1% (drying at 50°C for 96 h) for the FAX [36]. e moisture content can predict the microbial growth in the FAX sample, and the presence of moisture accelerates decomposition and generates toxins [37].

pH.
e pH helps us to deduce the solubility, stability, irritability, and permeability in biological membranes of a substance. Likewise, it determines the compatibility in formulations [17]. e pH was 5.81 ± 0.02 (see Table 2); however, this value is slightly more acidic than the pH  Journal of Food Quality (6.19 ± 0.03) of the AX from rice bran [38]. is may be due to the presence of uronic acid and a higher amount of free phenolic acids. Table 1 shows the result of total ash (2.68 ± 0.01%). It suggests the presence of residual nonvolatile inorganic substances. Generally, total ash is composed of metal oxides, carbonates, oxalates, and silicates [39]. Jacquemin et al. [40] found a high value (5.5%), and they suggested that it could be due to the presence of sodium metal derived from NaOH used during the extraction step.

Protein
Content. e protein content was 3.78 ± 0.02% (see Table 1), similar to the value obtained for the polysaccharide from wheat (3.70%) [41]. However, the protein content in the FAX reported by Mendez-Encinas et al. [42] was 8.2%. is result indicates that proteins in the FAX form a complex that cannot be easily destabilized even under treatment with alkaline hydrogen peroxide.

Micromeritic Analysis.
e results are summarized in the Table 1. e flow characteristic attributed to the FAX sample considering the angle of repose (20.04 ± 0.43°) was excellent. Hausner index (1.17 ± 0.02) and Carr index (14.35 ± 1.43%) indicated that the pulverized FAX presents a good flow. Our results are in line with the results of Erum et al. [43]. It should be noted that Pawar et al. [44] suggested that polysaccharides with good micromeritic properties can be used in the formulation of tablets prepared by direct compression. Figure 2(e) shows that an increase in the amount of the sample increased the intrinsic viscosity. e highest value of ηint was 1.983 ± 0.01 dL/g at 0.8% (w/v), and the lowest value was 0.121 ± 0.02 dL/g at 0.1% (w/v). Intrinsic viscosity reflects the hydrodynamic volume occupied by an individual polymer molecule. Previous studies reported intrinsic viscosity values from 0.8 to 5.48 dL/g [45].

Total Phenolic Content.
e TPC was calculated using the linear regression equation determined (Y � 1.4378X + 0.0413, R2 � 0.9966). Our result (5.722 ± 0.113 mg EAG/g) was lower than 67.66 ± 4.71 mg EAG/g [8]. e lower phenolic content is probably due to the fact that the germination of the corn kernel (during the elaboration of "chicha de jora") decreases the phenolic content, in agreement with the investigation of Ramadan et al. [46]. Likewise, Rao and Muralikrishna [47] showed a decrease in the phenolic content of FAX extracted from rice after a malting process. On the other hand, our result is slightly higher than the result previously reported for the polysaccharide (3.29 mg EAG/g) extracted from the corn bran [48], and these authors also conclude that the profile of hydroxycinnamic acids varies according to the extraction conditions and the source of the corn fiber. Figure 3 shows that the sample presented dark blue stains with similar migration to the standards of D-xylose and L-arabinose. However, the sample showed a tail-shaped stain probably related to the presence of other monosaccharides. e sample did not present a stain related to the D-glucose standard. e Rf and RG of the sample were similar to the standards of D-xylose and L-arabinose (Table 3). In qualitative terms, the identification of the monosaccharides determined by TLC was similar to that reported in the study by Saghir et al. [49]. Li and Du [50] reported that FAX has a low proportion of galactose. Figure 4(a) presents the chromatogram of the FAX hydrolyzed by acid methanolysis under parallel reaction monitoring of m/z 163.06112 with 5 peaks at Rt of 5.92, 6.62, 7.21, 7.47, and 7.69 min. Each peak has a mass spectrum with different fragmentation patterns, suggesting that the sample releases methylated pentoses with different spatial configuration, but similar molecular weight. Mass spectrometry does not allow discriminating compounds that have the same molecular weight and differ in the spatial arrangement, as is the case of L-arabinose and D-xylose (diastereomers at C-4). Figure 5(a) presents the mass spectrum in ESI (−) for the highest relative abundance peak (Rt, 7.21 min), with a first ion with m/z 163.0616. Mocsai et al. [51] suggest that the methylation of monosaccharides from FAX mainly shows methylation at C-3. e ions of m/z 145.05 and m/z 131.03 could correspond to the neutral loss by fragmentation of H 2 O and CH 3 OH, respectively, in concordance with spectrum reported by Nagar et al. [52]. Likewise, the fragment with peak m/z 59.01 agrees with the spectrum obtained for arabinopyranose (record PS109408) published in the MassBank mass spectra database (https://www.massbank. jp; accessed on 21 December 2021). erefore, it is suggested that the fragmentation pattern after hydrolyzing FAX would correspond to the presence of molecules of methyl-pentofuranosides or methyl-pentopyranosides (diastereomers).

Analysis by HPLC-MS/MS.
On the other hand, the chromatographic profile of the hydrolyzed FAX (see Figure 6(a)) determined under parallel reaction monitoring of m/z 193.0506 showed 5 peaks (tR 8.18, 9.32, 9.99, 10.86, and 11.17 min) with different fragmentation patterns. e spectrum of Figure 5(b) for the peak

UV-Vis Spectroscopy.
e UV-vis spectroscopy was made mainly for the identification of the ferulic acid, considering that the functional groups of the polysaccharides present little or no absorptivity in the UV-vis spectrum (Figure 2(f )). Regarding the peak at 280 nm, Guo et al. [55] indicated that it is related to the existence of proteins, which is consistent with the protein quantification. e arm at 325 nm, according to Li et al. [56], is attributed to phenolic compounds attached to arabinose residues. On the other hand, bands around 324 nm (n ⟶ π * transition of C�O and C�C bonds connected to the benzene ring) suggests the presence of units of conjugated phenolic compounds (ferulic acid and p-coumaric acid) [57].

Infrared Spectroscopy.
e infrared spectrum (Figure 7) shows characteristic absorption patterns and bands previously identified for FAX by Aslam Khan et al. [58] and Mo et al. [59]. e broad band at 3320 cm −1 is attributed to the stretching vibration of the hydroxyl functional group (-OH) [60]. e band pattern at 2970 cm −1 and 2880 cm −1 correspond to stretching vibrations of the saturated aliphatic group-CH2 [61]. Additionally, the absorption at 1380 cm −1 is assigned to the symmetric C�O strain, which was previously associated with the presence of uronic acid in the FAX structure [55]. e absorption at 1090 cm −1 corresponds to the C-O-C antisymmetric stretching vibration typical of the polysaccharide glycosidic bond, while a central band at 1050 cm −1 is assigned to the bending vibration of the C-OH bond [62]. At 880 cm −1 , a band was observed indicating the β configuration of the enantiomeric carbon of the pyranose units [54]. Like Li et al. [56] and Mo et al. [59], there was no evidence of absorption at 850 cm −1 associated with the α configuration of the furanose monosaccharide of arabinose. Likewise, the band at 616 cm −1 could be associated with C�C vibration of the aromatic ring of ferulic acid [63]. On the other hand, the IR spectrum obtained did not reflect the existence of proteins, which differs from the research carried out by De Anda-Flores et al. [64], in which the  0.70 1.14 * Md � migrated distance in cm from seeding origin, * * Rf � retention factor; * * * RG � retention factor relative to D-glucose. 8 Journal of Food Quality existence of proteins is suggested by showing absorption bands between 1640 and 1533 cm −1 .

Determination of Antioxidant Capacity In Vitro
3.9.1. DPPH• Assay. According to Table 4, FAX showed capacity to inhibit the DPPH• radical (between 0.5 and 10 mg/mL), which increased with the concentration. At 0.5 mg/mL, the inhibition % of the sample was lower (18.92 ± 0.84%), increasing until 61.66 ± 0.41% at 10 mg/mL. At 5 mg/mL, the inhibition% for the sample was 45.25 ± 0.74%, a value slightly higher than 42.64% for FAX from the corn bran [65]. e standard had a lower IC50 value (0.0128 mg/mL), which showed that Trolox has can inhibit the radical approximately 515 times higher than the sample (IC50, 6.5921 mg/mL). e IC50 value obtained was lower than the IC50 (1.3 mg/mL) previously reported for FAX from the rice bran [66]. Within the chemical structure of ferulic acid, the presence of the carbonyl group (-CO-) in the paraposition of the phenolic  ring causes the delocalization of electrons to give rise to the phenoxy radical [67] which gives the capacity to inhibit the radicals [68]. e Trolox equivalent antioxidant capacity (TEAC) of FAX was 7.7844 ± 0.08 μmol TEAC/g ( Table 3) lower than 18 μmol TEAC/g for FAX from corn residues derived from industrial ethanol production [23].

ABTS•+ Assay.
e greatest inhibition of ABTS•+ (71.17 ± 1.08%) occurred at 10 mg/mL; likewise, the lowest inhibition (0.90 ± 0.30%) was at 0.1 mg/mL (Table 4). Trolox presented an inhibition capacity of approximately 11 times greater than the sample after comparing their IC50 values. Our results are in agreement with the findings of El-Gizawy and Hussein [68], in which FAX presented higher antioxidant capacity in the ABTS•+ assay (aqueous medium) compared to the DPPH• assay (partially aqueous medium). FAX shows a hydrophilic behavior, so its antioxidant profile is favored in a medium of the same nature, which generates an increase in the effective concentration of ferulic acid in the aqueous medium [69]. Recently, Marquez-Escalante et al. [70] have reported that FAX from corn distiller's grains derived from industrial alcohol manufacture has an antioxidant capacity of 11.3 μmol TEAC/g in the ABTS•+ assay. On the other hand, our result is close to the value previously reported by Paz-Samaniego et al. [71] of 39.2 ± 1 μmol TEAC/g.

FRAP Assay.
e FRAP assay measures the potential of an antioxidant to reduce the ferric ion (Fe 3+ ) to produce the blue-colored ferrous ion (Fe 2+ ) in a low pH medium [72]. In Table 4, the FRAP value of the sample was 36.6 ± 0.3 μmol Fe 2+ /g, which is higher than the value (5.6 μmol Fe 2+ /g) previously reported by Hu et al. [73] for commercial FAX. A slightly higher FRAP value (49 μmol Fe 2+ /g) was obtained for FAX from the residual malted barley grains derived from beer production [74]. However, our result was lower than 786.2 μmol Fe 2+ /g [75]. Figure 8 shows that the sample can adsorb 1.81 ± 0.21, 2.82 ± 0.25, 6.21 ± 1.23, and 8.10 ± 1.63 mmol/g of glucose. A greater amount of glucose in the medium shows greater amounts of glucose bound to the polysaccharide. e results are indicative that FAX can effectively adsorb glucose, and thus, it could play an important role in lowering postprandial glucose concentrations. e CAG of the sample was greater than the reported value for the insoluble dietary fiber polysaccharide of the rice bran (0.01-1.04 mmol/g) [75] and slightly lower than the insoluble dietary fiber polysaccharide of the foxtail "Setaria italica" bran (3.72-16.74 mmol/g) [26]. e CAG is related to the molecular weight of the polysaccharide [76].

Glucose Diffusion Inhibition Capacity.
e glucose diffusion inhibition assay is useful for predicting the effect of a polysaccharide in order to delay the glucose absorption in the gastrointestinal tract [27]. Figure 9 shows that, within each treatment group (negative control, acarbose, FAX 1 mg/mL, FAX 10 mg/mL, and FAX 25 mg/mL), a statistically significant difference (p < 0.05) was observed. e increase in the concentration of glucose in the external medium increased rapidly up to 60 min in concordance with the results previously reported for FAX extracted from triticale [77] and for the polysaccharide extracted from Tuber aestivum [78]. A comparison with the negative control group allowed us to observe that FAX 10 mg/mL at 30   (p < 0.05), and the other groups inhibited glucose diffusion, but no significant difference was found (p > 0.05).
Only FAX 25 mg/mL at 90 min showed a statistically significant difference compared with the acarbose. ese results may be related to the high viscosity, in which the polysaccharide develops a barrier on the dialysis tube, which reduces the diffusion of glucose. e ability to inhibit glucose diffusion of the polysaccharides may be due to factors such as degree of viscosity, adsorption capacity, formation of physical obstacles, and the ability to trap glucose within a network [79].

α-Amylase Inhibition Capacity.
Inhibition of the enzymatic activity of α-amylase may contribute to delaying the increase in postprandial blood glucose levels by decreasing glucose release and delaying its absorption [80]. Among the seven different concentrations (Figure 10), the highest inhibition (46.6 ± 0.42%) occurred at 5 mg/mL of sample; however, at the same concentration acarbose reached an inhibition of 88.7 ± 0.33%. When the concentration of FAX was 0.1 mg/mL, the inhibition was lower (11.51 ± 0.88%) compared to acarbose (

Sample
In vitro assay DPPH• ABTS•+ FRAP IC50 (mg/mL) TEAC (μmol/g) IC50 (mg/mL) TEAC (μmol/g) FRAP value (μmol AA/g) FRAP value (μmol Fe +2 /g) FAX 6.59 ± 0.03 * 7.7844 ± 0.08 * 6.50 ± 0.08 * 35.347 ± 0.94 * 14.081 ± 0.11 * 36.63 ± 0.29 * Trolox 0.013 ± 0.0001 * -0.059 ± 0.0001 * --- * All the results are expressed as the mean ± S.D. (n � 3). (IC50 � 5 mg/mL) previously reported for the polysaccharide of the wheat bran [81]. Polysaccharides can limit the rate of digestion of starch by the enzyme α-amylase in two ways [82]. First of all, polysaccharides can form a barrier that decreases or prevents the interaction of the digestive enzyme with starch. Secondly, the chemical nature of the polysaccharides may be related to the inhibition of α-amylase. It has been shown that a high presence of free carboxylic groups, hydroxyl, and methoxy group inhibits the enzymatic hydrolysis of starch [83]. e FAX presents a competitive type inhibition [76]. It should be noted that it is necessary to develop in vivo studies to evaluate the antihyperglycemic capacity of FAX.

Conclusions
In the present study, the extraction of FAX from the bagasse of "chicha de jora" was achieved by the alkaline hydrogen peroxide method, the dialyzed polysaccharide with molecular weight ≥3.5 kDa had an extraction yield of 19.87 ± 4.56%. e physicochemical analysis allowed corroborating the physicochemical characteristics of the FAX obtained, while the spectrophotometric analysis confirmed the presence of the typical structure of the polysaccharide. e sample shows in vitro antioxidant and antihyperglycemic capacity.

Data Availability
e data used to support the findings of this study are included within the article.