Determination of Antioxidant Activity and Proximate Composition of a Variety of Red Pigmented Zea mays L. from Puebla, Mexico

Abstract

Corn is one of the most consumed cereals in the Mexican diet. In this country, there are multiple varieties that exhibit nutraceutical potential due to their content of different metabolites with biological activity, such as blue corn. Another variety that has received little study is the red pigmented corn variety Chilac from Puebla, Mexico, which is being studied for its nutraceutical potential. A differential extraction using the Soxhlet method was carried out to evaluate the phenolic content, total flavonoid content, and monomeric anthocyanins, and free radical scavenging test was performed using the DPPH reagent. A proximate analysis was also conducted to identify the main macronutrients. The results of the proximate analysis were comparable to those of other traditional corn varieties, with carbohydrates being the macronutrient present in the highest amount at 77.9%. Regarding phenolic content and the presence of anthocyanins, the best extractions were obtained using alcoholic solvents; for example, ethanol for phenols, yielding 1368.420 ± 104.094 mg of gallic acid equivalents (GAE)/kg plant. In contrast, the flavonoid content was higher in the aqueous extract, with 833.984 ± 65.218 mg QE/Kg. In the case of the DPPH assay, the best result was obtained with ethyl acetate (73.81 ± 5.31%). These findings provide a foundation for expanding the use of corn varieties with nutraceutical potential, opening the possibility of studies focused on deeper characterization.

1. Introduction

Corn is one of the most widely cultivated cereals and is a staple part of the Mexican diet. In Mexico, 64 varieties of corn are cultivated, which differ in shape, size, texture, and color [1]. Native and pigmented corn is cultivated in Puebla, Guerrero, Oaxaca, Estado de Mexico, and Chiapas, mainly [2]. These types of corn kernels are currently produced only in small amounts and for self-consumption by the communities that produced them [3].

Pigmented maize varieties are rich in secondary metabolites, many of which are bioactive and contribute to pigmentation, particularly flavonoids [4]. Among these, anthocyanins represent a key subclass, predominantly found in glycosylated forms, which confer water solubility and are responsible for orange, red, blue, and purple colorations [5]. Structurally, anthocyanins are characterized by a benzopyran core comprising a benzoyl ring (A) and pyran ring (C), with a phenolic ring (B) attached at the 2-position and a sugar moiety primarily located at the 3-position of the C ring [6]. Approximately 90% of naturally occurring anthocyanins derive from six main aglycones, which differs from the substitution pattern of the B ring: cyanidin (Cy) accounts for ~50%, while delphinidin (Dp), pelargonidin (Pg), and peonidin (Pn) each represent ~12%, and petunidin (Pt) and malvidin (Mv) about 7% each [7]. The chromatic properties of anthocyanins depend on the degree and position of hydroxylation and methoxylation within their structure. Increased hydroxylation is associated with a shift toward bluish tones, whereas greater methoxylation enhances reddish hues [8]. Beyond their role in pigmentation, anthocyanins exhibit a range of biological activities, including anticancer [9], hypoglycemic, antioxidant [10], antibacterial [11], anti-inflammatory [12], and immune-modulatory activities [13]. Another phenolic compound found in corn and red-pigmented varieties is phlobafen, condensed tannins of high molecular weight [14]. Together with its antioxidant capacity, it could represent a bioactive metabolite of health importance; however, more research is still needed.

Red corn is integral to the diets and traditions of many indigenous communities, particularly in Latin America. In countries, such as Mexico and Guatemala, red corn is used in traditional dishes like tamales, atole, and tortillas and is central to rituals and festivals [15,16]. Studies have compared the content of secondary metabolites, phenolic compounds, and antioxidant capacity of red and blue corn. The results showed that the corn samples with the highest biological activity were those with blue color, while the least active were those with red color [14]; however, the importance of pigmented corn lies in its nutritional, cultural, and ecological significance. This is due to the change in the levels of different anthocyanins resulting from genetic variations and environmental conditions, resulting in different colors in the corn kernels.

Red-pigmented corn can be used as a functional food; however, its nutritional profile needs to be evaluated as there are limited reports on the nutritional potential of red-pigmented corn [17]. Some of these studies report a higher percentage of relevant macronutrients, such as protein, compared to white, yellow, or even some blue-pigmented varieties [18]. The antioxidant capacity has also been evaluated using free radical assays such as DPPH and ABTS, along with the determination of total phenols, flavonoids, and anthocyanins. The results (subject to variation depending on the extraction method and the origin of the sample) reflect a matrix rich in biologically active metabolites [19,20].

The objective of this study was to evaluate the nutritional composition, the phenolic profile and the antioxidant capacity of red-pigmented corn variety grown in Puebla, Mexico, to determine the nutritional and antioxidant potential of this variety in comparison with other varieties from Mexico. It is expected that the proximal analysis will reveal a macronutrient composition like that of commonly consumed varieties, and additionally, a significant presence of antioxidant metabolites.

2. Materials and Methods

Sample

The original seed was collected in 2008 from San Gabriel Chilac, Puebla. This seed began a process of adaptation to other regions and has been selected for uniformity and intensity of grain color, called Zea mays L. Variety Chilac. Finally, the seed was obtained as a donation in 2022 from Huejotzingo, Puebla.

Sample preparation

The sample was crushed using a manual mill and then ground to a fine powder using an electrical grinder to obtain a more homogeneous sample as mesh No. 40.

Extraction of phenolic compounds

A total of 20.0 g of sample was placed in a Soxhlet Evelsa^® equipment by differential system with 180 mL of solvent (hexane, ethyl acetate (AcOEt), dichloromethane (DCM), ethanol, methanol, and distilled water) at a reflux temperature for each solvent at 1 bar pressure in sequence for 3 h each; then all the solvent was removed, and a stock solution was prepared at 1 mg/mL with methanol at 80% [21].

Phenolic compounds analysis

The total phenolic content (TPC) was determined according to the Folin–Ciocalteau assay reported by [18] with some modifications. The extracts (150 μL) were transferred into cuvettes, and their volumes were made up to 2.4 mL with distilled water and oxidized with the addition of 150 μL of Folin–Ciocalteau reagent. Then, the mixture was neutralized with the addition of 450 μL of 12% aqueous ${\mathrm{N}\mathrm{a}}_2{\mathrm{C}\mathrm{O}}_3$ solution after 5 min of reaction. Mixtures were allowed to stand at ambient temperature and isolated from light for 2 h until the characteristic blue color developed. Absorbance of each sample was measured at 760 nm against a blank containing 80% methanol and a positive control containing 0.1 mg/mL gallic acid [18]. The total phenolic content of each sample was determined by means of a calibration curve prepared with gallic acid and expressed as mg of gallic acid equivalents (GAE) per kg of plant (mg GAE/kg of plant).

TPC was calculated by the following formula [21]:

$$\mathrm{T}\mathrm{P}\mathrm{C}=\left[\left(c_{GA}\right)\left({\displaystyle \frac{1}{c_E}}\right)\left({\displaystyle \frac{m_E}{m_P}}\right)\right]\times 1000$$

(1)

where $c_{GA}$ is the concentration of gallic acid (GA) in milligrams of equivalents of GA per milliliter of extract (mg GAE/mL extract); $c_E$ is the concentration of extract; $m_E$ is the mass of the extract in grams (g); and $m_P$ is the mass of the sample placed in Soxhlet in grams (g).

Flavonoid compounds analysis

The total flavonoid content (TFC) was determined using aluminum chloride in a colorimetry method [18]. Briefly, 4000 μL of distilled water was transferred into test tubes and mixed with 1000 μL of the sample. Then, 300 μL of a 10% ${\mathrm{A}\mathrm{l}\mathrm{C}\mathrm{l}}_3$ solution was added to form a flavanoid–aluminum complex. After 5 min, 2000 μL of 1 M NaOH was mixed with each extract. Their volumes were made up to 10 mL with distilled water. Mixtures were allowed to stand at ambient temperature and isolated from light for 40 min. The absorbance of each sample was measured at 510 nm against the blank containing 80% methanol and a positive control containing 0.1 mg/mL quercetin. The total flavonoid content was expressed as mg of quercetin equivalents (QE) per kg of plant.

TFC was calculated by the following formula [21]:

$$C=\left[\left(c_Q\right)\left({\displaystyle \frac{1}{c_E}}\right)\left({\displaystyle \frac{m_E}{m_P}}\right)\right]\times 1000$$

(2)

where $c_{\mathrm{Q}}$ is the concentration of quercetin (Q) in milligrams of equivalents of quercetin per milliliter of extract (mg QE/mL extract); $c_E$ is the concentration of extract; $m_E$ is the mass of the extract in grams (g); and $m_P$ is the mass of the sample placed in Soxhlet in grams (g).

Anthocyanin content analysis

The total monomeric anthocyanin content (TMAC) was quantified by the differential pH method [22]. This is a spectrophotometric method based on the structural transformation of anthocyanins with a pH change (pH 1 colored and pH 4.5 colorless). Dilutions of all extracts were prepared with pH 1.0 potassium chloride buffer solution and pH 4.5 sodium acetate buffer solution, 1:100 dilution of ethanol and methanol extracts, 1:10 dilution of hexane and aqueous extracts, and 1:40 dilution of the AcOEt and dichloromethane extracts. The absorbance of each sample was measured at the absorption maximum wavelength (λmax = 515 nm) and at 700 nm.

TMAC was calculated by the following formula [23]:

$$TMAC={\displaystyle \frac{\left(A\right)\left(MW\right)\left(DF\right)}{\epsilon }}\times 1000$$

(3)

where $A=\left(A_{515\mathrm{n}\mathrm{m}}-A_{700\mathrm{n}\mathrm{m}}\right)\mathrm{p}\mathrm{H}1.0-{(A}_{515\mathrm{n}\mathrm{m}}-A_{700\mathrm{n}\mathrm{m}})\mathrm{p}\mathrm{H}4.5$; MW (molecular weight) = 449.2 g/mol for cyanidin-3-glucoside (cyd-3-glu); DF is the dilution factor; and $\epsilon$ = 26,900 M extinction coefficient in L mol⁻¹ cm⁻¹ for cyd-3-glu.

Analysis of DPPH scavenging capacity

An amount of 25 µL of each extract was transferred into the wells of the Elisa plate, then 200 µL of the DPPH free radical solution was added. Mixtures were allowed to stand at an ambient temperature isolated from light for 40 min. The absorbance of each sample was measured at 492 nm against the blank containing 80% methanol and a positive control containing 0.015 mg/mL gallic acid. The results were expressed as a percentage of inhibition [24].

Radical scavenging capacity was calculated by the following formula [25]:

$$\%\mathrm{I}\mathrm{n}\mathrm{h}\mathrm{i}\mathrm{b}\mathrm{i}\mathrm{t}\mathrm{i}\mathrm{o}\mathrm{n}=[\left(A_B-A_A\right)/A_{\mathrm{B}}]\times 100,$$

(4)

where $A_B$ is the absorption of blank sample and $A_A$ is the absorption of tested extract solution.

Determination of proximate composition

Analysis of moisture content

The sample was studied gravimetrically by drying 3 g of crushed sample in a thermobalance at 120 °C for 20 min until it reached constant weight [26]. The percentage of moisture was calculated with the following formula with some modifications [27]:

$$\%=\left({\displaystyle \frac{W_i-W_f}{W_i}}\right)100$$

(5)

where W_i is the initial weight, and W_f is the final weight.

Analysis of lipid content

The lipid content was determined via the Soxhlet extraction method [28,29]. Five grams of the sample were placed in a filter paper cartridge (at constant weight) and then placed in the Soxhlet equipment with 10 mL of hexane for 3 h. Once the process was finished, the cartridge was dried to constant weight, and the percentage of lipid was determined with the Formula (5) with some modifications [26].

Analysis of mineral content

Three grams of the dry sample were placed in a crucible (at constant weight) and calcined using an electric burner. The crucible was then placed in a muffle and heated at 550 °C for 12 h [28,29]. The percentage of minerals was determined with Formula (5) [30].

Analysis of protein content

The protein was estimated by Bradford assay [31]. The protein content in the sample was measured by the absorbance (570 nm) with a plate reader and different concentrations of BSA were prepared as a standard. The protein content was estimated to a calibration curve and expressed in percentage of dry weight.

Analysis of fiber content

The crude fiber percent was determined using the Weende method with the aid of FIWE automated equipment. The sample was subjected to a chemical digestion process, first with sulfuric acid (1.25%), after potassium hydroxide (1.25%) [28,29]. Subsequently, it was placed in a muffle at 105 °C to obtain W₂ by bringing the crucible to constant weight. Finally, it was calcined in a muffle at 550 °C for 12 h and once again brought to constant mass to obtain W₃. The percentage of fiber was determined to following formula with some modifications [30]:

$$\%=\left({\displaystyle \frac{W_2-W_3}{W_1}}\right)100$$

(6)

where W₁ is the initial weight, W₂ is the previous calcination weight, and W₃ is the calcination weight.

Analysis of carbohydrate content

The carbohydrate content was calculated using the differential method [28]. The percentage was calculated using the following formula [32]:

$$\mathrm{\%}\mathrm{C}\mathrm{a}\mathrm{r}\mathrm{b}\mathrm{o}\mathrm{h}\mathrm{y}\mathrm{d}\mathrm{r}\mathrm{a}\mathrm{t}\mathrm{e}=100\mathrm{\%}-(\mathrm{\%}\mathrm{m}\mathrm{o}\mathrm{i}\mathrm{s}\mathrm{t}\mathrm{u}\mathrm{r}\mathrm{e}+\mathrm{\%}\mathrm{m}\mathrm{i}\mathrm{n}\mathrm{e}\mathrm{r}\mathrm{a}\mathrm{l}+\mathrm{\%}\mathrm{l}\mathrm{i}\mathrm{p}\mathrm{i}\mathrm{d}+\mathrm{\%}\mathrm{p}\mathrm{r}\mathrm{o}\mathrm{t}\mathrm{e}\mathrm{i}\mathrm{n}+\mathrm{\%}\mathrm{f}\mathrm{i}\mathrm{b}\mathrm{e}\mathrm{r})$$

(7)

Statistical Analysis

All data were obtained in triplicate as well as from independent samples. The total data were statistically analyzed by Kruskal–Wallis accompanied with Mann–Whitney U test in Minitab 18.0 software and the results are expressed in means with letter assignment to identify statistically different groups for p < 0.05.

3. Results and Discussion

The first thing presented (

Table 1. Amount of extract obtained with each solvent.

Solvent	Extract (g Extract/kg ± std. dev.) 1
Hexane	31.40 ± 5.38 A
AcOEt	8.54 ± 4.27 B
DCM	6.55 ± 3.64 B
Ethanol	19.04 ± 4.55 C
Methanol	14.51 ± 3.84 C
Water	6.06 ± 0.66 B

¹ Mean values with different letters indicate significant differences p ≤ 0.05, (p = 5.4 × 10⁻⁷ Kruskal–Wallis test).

) is the ratio of extract obtained with each solvent, the use of these six solvents allows the sequential extraction of compounds with variable polarity, in addition, the use of this methodology has yielded optimal results in both the extraction of essential oils and the isolation of fractions containing biologically relevant metabolites [33].

Subsequently, in the next section it is evident that most phenolic compounds are more abundant in alcoholic solvents compared to aqueous solvents. This observation may be attributed to the nature of the metabolites reported, such as ferulic acid and curamyl acid [34]. Their chemical structures, characterized by hydroxyl groups, exhibit a stronger affinity for polar solvents [35]. To demonstrate this, the influence of the solvent on the extraction efficiency of phenols, flavonoids, and anthocyanins in different pigmented corn varieties has been investigated compared to the 1500 and 1300 mg/kg reported for the cherry red and brick red varieties, respectively, for methanol, which places it in the characteristic range of red varieties, confirming that the most effective solvents are polar, such as methanol or aqueous acetone [20], consistent with our findings.

A similar phenomenon is observed in the determination of flavonoids. The higher content observed in the aqueous extract may be due to the predominance of water-soluble flavonoid glycosides in the red corn variety, which have a greater affinity for more polar solvents [36] (

Table 2. Phenolic content of red-pigmented corn extracts.

Solvent	Folin–Ciocalteu (mg GAE/kg ± std. dev.) 1
Hexane	46.618 ± 9.636 A
AcOEt	54.474 ± 10.344 A
DCM	69.054 ± 10.498 B
Ethanol	1292.080 ± 126.571 C
Methanol	1368.420 ± 104.094 C
Water	846.154 ± 98.140 D

¹ Mean values with different letters indicate significant differences p ≤ 0.05, (p = 7.1 × 10⁻⁸ Kruskal–Wallis test).

). It is well established that among the wide range of flavonoids present in pigmented corn varieties, anthocyanins are predominant and are primarily associated with the grain’s pericarp [37]. Interestingly, notable results were also observed with hexane, the least polar solvent used. This suggests the involvement of lipophilic metabolites, such as tocopherols and carotenoids, which have been identified in other studies. For example, the yellow variety primarily contains lutein, zeaxanthin, and β-carotene. These carotenoids are also present in other pigmented varieties, albeit in lower concentrations. Moreover, λ-tocopherol has been identified as the predominant tocopherol in the grain, with a value of 1664 mg/kg for acidified extract for red variety, being higher for other varieties; however, the acidified technique combines in the extraction together with anthocyanins, flavones, and flavonols, thus explaining the increase [38]. Based on previous reports (

Table 3. Flavonoid content of red-pigmented corn extracts.

Solvent	Flavonoids (mg QE/kg ± std. dev.) 1
Hexane	349.349 ± 32.341 A
AcOEt	106.872 ± 21.436 B
DCM	84.706 ± 12.987 B
Ethanol	613.813 ± 68.854 C
Methanol	573.706 ± 32.787 C
Water	833.984 ± 65.218 D

¹ Mean values with different letters indicate significant differences p ≤ 0.05 (p = 2.7 × 10⁻⁸ Kruskal–Wallis test).

), the results appear to be comparable, despite variations in extraction methods, the type of control used, and the soil and climatic conditions specific to each study.

Finally, among the group of metabolites of great importance in the antioxidant capacity field are anthocyanins, which are naturally water-soluble compounds (

Table 4. Content of monomeric anthocyanins in red-pigmented corn.

Solvent	Anthocyanins (mg cyd-3-glu Equivalent/kg ± std. dev.) 1
Hexane	No monomeric anthocyanins detected
AcOEt	No monomeric anthocyanins detected
DCM	No monomeric anthocyanins detected
Ethanol	772.240 ± 83.136 A
Methanol	822.884 ± 43.885 A
Water	47.796 ± 8.84 B

¹ Mean values with different letters indicate significant differences p ≤ 0.05, (p = 1.6 × 10⁻⁵ Kruskal–Wallis test).

), and a type of flavonoids with high pH sensitivity [39]. This explains their absence in the initial extractions using low-polarity solvents. In this case, the use of alcoholic and aqueous solvents demonstrates an efficient capacity for extracting metabolites of this nature [40]. Additionally, the natural glycosylation of anthocyanins should be considered when analyzing their polarity, as the addition of hydroxyl groups increases their affinity for solvents with high dielectric constants [41]. In contrast to previous reports ranging from 180 to 790 mg/kg such as cherry red and blue-purple, it was higher in the variety studied, increasing its nutraceutical value associated with anthocyanins [20]. This discrepancy may be attributed to differences in the extraction method and the geographical origin of the sample.

In the case of DPPH radical scavenging capacity (Figure 1), it is worth noting that among the best solvents are methanol, ethanol, and water, which is predictable based on the results obtained in the metabolite profile shown above; however, ethyl acetate exhibits an ability to inhibit DPPH with same the efficiency as water (backed by statistical analysis). This can be explained by the presence of low-polarity metabolites with antioxidant capacity, such as carotenoids and tocopherols. The fact that this phenomenon occurs only in ethyl acetate is due to the relationship between the dielectric constant of the three solvents. There is a noticeable in dielectric constant from hexane to acetate, which facilitates the extraction of these metabolites. However, the increase between dichloromethane and ethyl acetate is less pronounced. In previous studies analyzing purple, red, yellow, and white varieties, the report IC₅₀ values are consistent with those obtained from our alcoholic and aqueous extracts [34]. However, it is worth nothing that in this and other analyses, attention is often focused on the less polar fractions, which limits the availability of direct points of reference.

The high levels of phenolic compounds, flavonoids, and anthocyanins detected in the red-pigmented maize analyzed in this study, particularly in the polar extracts, support its classification as a potential functional food. These metabolites are strongly associated with antioxidant capacity, as demonstrated by the DPPH radical scavenging assay and previously report correlations, where they mainly analyzed the phenolic content [42]. Regarding anthocyanins, extracts with elevated levels of cyanidin-3-O-glucosyde have been shown to exert multiple biological effects, including anti-inflammatory, antidiabetic, and antiproliferative activities in vitro. Notably, certain studies suggested that maize-derived metabolites can improve paracrine interactions between adipocytes and macrophages, thereby positively modulating processes such as oxidative stress and insulin resistance [43]. Similarly, antiproliferative effects have been reported in human cancer cell lines treated with extracts from native blue maize, which contains metabolite concentrations comparable to those observed in our study [44].

The nixtamalization reduces the anthocyanin and phenolic compounds presents in corn dough after boiling, due to high temperatures. A study determined the polyphenols and anthocyanin concentration in fermented beverages from blue corn, reporting that the polyphenols were reduced by 42–54% during boiling, increasing slightly after fermentation back up to 74%. In some other fermented beverages, only the antioxidant effect has been reported due to the synergy between antioxidants [45].

The data obtained in the determination of the proximate composition of red-pigmented corn are shown in

Table 5. Proximate composition of red-pigmented corn.

Parameter	Red-Pigmented Corn Studied (%)
Moisture	6.49 ± 0.10
Ash	3.07 ± 0.35
Lipids	7.11 ± 0.59
Crude Fiber	1.15 ± 0.30
Protein	4.21 ± 0.21
Carbohydrates	77.97 ± 0.80

. A moisture of 6.49 ± 0.10% is observed, which is lower than that reported for native varieties of blue colorations in India and red in Nigeria with 12.52% and 12.10%, respectively [46,47], although a study by Rivera-Castro et al. (2020) [48] of purple-colored native corn presented a moisture of 7.24% and a white coloration of 5.86%, which is a result closer to that obtained in this study. Low moisture values in seeds should be considered an advantage because they help storage stability and food quality; therefore, seeds with high moisture content are subject to rapid deterioration due to mold growth and insect damage [49].

Regarding ash concentration, it is found at 3.07 ± 0.35%, being higher than that reported for other Mexican varieties that ranged between 0.8 and 1.42% [48,50]. The type of soil can be very important in the content of mineral compounds quantified in the ashes and shows us an approximate content of the total amount of minerals present in the food. This, in turn, influences the bioavailability of micronutrients derived from this type of food. The higher mineral content found in this maize could be beneficial in the prevention of micronutrient deficiencies, such as iron-deficiency anemia.

The lipid content present was 7.11 ± 0.59, this value turned out to be higher than the value found in Mexican varieties that fluctuated between 3.97 and 5% [50,51]. This makes it possible to offer a maize that has a higher energetic contribution compared to other varieties; in addition to that, this type of grain can be a source of fatty acids that are beneficial in a balanced diet. Meanwhile, the proportion of crude fiber was 1.15 ± 0.30, similar to that reported in varieties from northern Mexico [50] with values of 0.63–1.2% and the different corn crops (1.24–2.07%) found by Kabir et al. (2019) [52]. But higher values were reported in varieties of blue corn (5.47%) and purple native corn (7.06%) [39,48]. It can be said that the versatility of these nutrients depends largely on the variety of each seed.

The protein content for red-pigmented corn was 4.21 ± 0.21, similar to that reported by Michel et al. (2020) of 4.56% in a variety from northern Mexico [50]; however, this nutrient is found with low values with respect to a red-colored variety from Nigeria (12.82%) [47], the variety from Bangladesh (11.47%) [52], and even the one reported by Rivera-Castro et al. (2020) [48] in purple native corn (9.02%). In this context, high protein content may result in the depletion and imbalance of other macronutrients. Moreover, it is frequently associated with increased application of nitrogen-based fertilizers, which could account for the absence of such an effect in the variety analyzed in this study. Another reason included the variety of maize, the use of field management techniques, soil, and climatic conditions that directly affect the chemical composition.

Corn kernels are primarily composed of starch, which serves as a consistent carbohydrate source for both humans and livestock. In our case, carbohydrates represent about 78% of the dry weight of the grain, while in some varieties this can reach up to 84% [51]. Foods with high carbohydrate content may offer health benefits, as they provide substrate to produce short-chain fatty acids, which play a key role in modulating immune responses and inflammatory process.

This study lays the basis for the future development of functional foods or nutraceutical products based on red corn, which could contribute to the prevention of oxidative stress-related diseases. In the long term, it could support strategies aimed at improving public health through culturally relevant and locally sourced ingredients; however, it is still necessary to further investigate the variability that may exist between different varieties, or even within the same variety grown under different conditions. To address this, a more extensive study including more samples from different locations and providing more precise characterization of their composition would be important.

4. Conclusions

The red-pigmented maize analyzed in this study exhibited a high content of phenolic compounds, flavonoids, and anthocyanins, particularly in extracts obtained with highly polar solvents. This compositional profile was strongly associated with elevated antioxidant capacity. These characteristics are a promising candidate for functional food development due to its capacity to contribute to the prevention and management of various high-incidence pathologies. Nevertheless, its cultivation remains geographically limited, mainly due to the widespread presence of high-yielding maize varieties such as yellow and white maize. Studies like this contribute to a more comprehensive characterization of underexplored plant matrices, offering alternative food sources with potential applications not only in the nutritional sector but also in specific industrial context.