Mineral Content of Four Mexican Edible Flowers Growing in Natural Conditions and Backyards from Indigenous Communities

Abstract

The objective of this study was to evaluate the variation in the mineral concentrations of the inflorescences of Yucca filifera (izote), Agave salmiana (maguey), Diphysa americana (cuachepil), and Chamaedorea tepejilote (tepejilote) in samples collected from different communities in Oaxaca, Mexico. For each sample, the concentrations of macro- and microelements were determined via inductively coupled plasma–optical emission spectrometry (ICP-OES). For each species, significant differences (p < 0.05) in mineral contents were detected on the basis of geographic sampling origin, both among and within locations, for all the minerals evaluated except for Na in all the cases, Cu in izote and tepejilote, and Si in maguey. The macro- and microelement patterns range from highest to lowest concentrations were as follows: K > Ca ≥ P > Mg > S > Na and Si > Fe ≥ Zn > Mn > Cu > Mo. High values were recorded in tepejilote, whereas low values were observed in cuachepil, maguey pulquero, and izote. The average values between species ranged from 199.1 to 3650.3, 243.6 to 3383.7, 354.8 to 941.7, 164.5 to 1281, 76.2 to 1142.9, 1.3 to 44.7, 4.27 to 201, 2.41 to 13.67, 3.08 to 9.23, 0.81 to 13.65, and 0.52 to 3.09 mg 100 g⁻¹ dw in K, Ca, P, Mg, S, Na, Si, Fe, Zn, Mn, and Cu, respectively, indicating a nutritional source in the regions where they are distributed.

1. Introduction

In Mexico, approximately 250 species of ‘quelites’ (quilitl in the Nahuatl language) or traditional plants are recognized, including complete plants or organs of edible plants, products of the collection of wild or ruderal forms, and tolerated or cultivated forms. Among these groups of quelites are edible flowers, or flower quelites, with approximately 100 species (49 genera and 25 families), where the flowers are the food sources that are consumed fresh or processed; these quelites have been consumed since pre-Columbian times in the Mesoamerica region [1]. In general, flower or inflorescence quelites provide water, fiber, protein, and minerals; however, few or no evaluations or references concerning the chemical composition of the diverse species with edible flowers or inflorescences distributed and consumed in Mexico, Latin America, and different regions of the world exist. In addition, studies on traditional or conventional vegetables are typically aimed at evaluating the composition of leaves and/or tender stems but not flowers [2,3,4,5]. The structural, morphoanatomical, and functional differences between flowers and young edible leaves/stems can lead to differences in their chemical compositions [6].

In recent decades, interest in edible flowers from both consumers and food researchers has increased, not only in traditional edible flowers (e.g., cauliflower, broccoli, artichoke, hibiscus, and pumpkin flowers) but also in ornamental flowers and/or aromatics (e.g., rose and chrysanthemum) to be consumed fresh, cooked, or processed. When fresh, they add color or aesthetic value to dishes, and when processed, they add flavor, texture, aroma, and combinations of exotic flavors. However, their dietary contributions in terms of functional compounds and nutritional composition need to be understood [7,8,9,10]. In general, vegetables provide water, proteins, carbohydrates, and fatty acids and are essential sources of micro- and macroelements, both for enzymatic and structural–functional metabolic functions, and the amounts of these components that they contribute vary from species to species based on genetic and ontogenetic aspects, growth conditions, and forms of processing [11].

The most recent studies have shown that edible flowers contain high contents of macroelements such as K, P, and Mg and microelements (Fe, Zn, and Mn) [12,13,14] and are potential sources of minerals. The consumption of flowers enhances familiar nutrition and prevents health problems associated mainly with food [7,15]. For example, K, Ca, Mg, and P are associated with many biological processes, such as risk reductions against cardiovascular diseases, osteoporosis, kidney diseases, diabetes, LDL cholesterol, and colorectal cancer [16,17]. Similarly, Zn, Fe, Cu, and Mn are cofactors in a series of enzymes related to physiological–functional processes involved in cell homeostasis, the immune system, bone metabolism, the central nervous system, and wound healing, among other processes [18,19,20,21].

In Mexico, the flowers of various species of Agave (e.g., A. angustifolia, A. americana, and A. salmiana), Yucca (e.g., Y. filifera, Y. schidigera, and Y. elephantipes), Diphysa americana, and Chamaedorea tepejilote are significant nutritional sources for diverse cultural groups [22,23,24]. Like other legumes, seeds, and edible leaves, the flowers of A. salmiana and Y. filifera contain essential amino acids, fiber, and crude protein; in addition, they contain phenolic compounds and flavonoids and have antioxidant activity [25,26,27]. Extracts of A. salmiana flowers can inhibit the growth of Gram-negative bacteria [28]. The flowers of Chamaedorea tepejilote contain vitamins, macro- and micronutrients of nutritional importance (Ca, K, Mg, Na, Fe, Zn, and Cu), fiber, carbohydrates, and high protein content [22,29,30]. The flowers of Diphysa americana are rich in minerals such as Zn, Ca, and Mg, as well as protein and fiber, and contain phenolic compounds and flavonoids [23]. However, little is known about their nutritional potential and health benefits, and even less is known about their macro- and microelement contents and their variation with respect to the ecogeographic origin of growth.

Previously, Pascual-Mendoza et al. [31] evaluated eight Mesoamerican species of quelites collected in Oaxaca, Mexico, and estimated variations in P, K, Ca, Mg, Na, Cu, Fe, Mn, Zn, and B contents, for example, values ranging from 255.6 to 1785.6, 7.8 to 30.8 and from 2.32 to 10.6 mg 100 g⁻¹ in fresh weight of Ca, Fe, and Zn, respectively. In edible flower species, Grzeszczuk et al. [32] evaluated the mineral content of eight species with variations in macroelements, such as P (6.01–9.16 g kg⁻¹), K (8.15–54.45 g kg⁻¹), Na (0.04–1.27 g kg⁻¹), Ca (0.43–17.6 g kg⁻¹), Mg (1.10–4.79 g kg⁻¹), and S (0.27–1.58 g kg⁻¹), and microelements, such as Fe (21.8–683.5 mg kg⁻¹), Zn (12.61–42.76 mg kg⁻¹), Cu (2.92–19.35 mg kg⁻¹), and Mn (6.02–30.64 mg kg⁻¹). Ghosh and Rana [33] estimated the average concentrations of 0.75, 1.23, 2.75, 4.23, 11.5, 17.6, and 18.2 mg 100 g⁻¹ of Cu, S, Mg, Fe, Na, Ca, and K, respectively, in pumpkin flowers (Cucurbita maxima L.), and they reported that Ca and K are elements with potentially greater contributions to this food source. In Yucca gloriosa L. from Racht, Iran, Nicknezhad et al. [34] reported concentrations of 0.27, 2.51, 2.54, and 14.6 mg 100 g⁻¹ Zn, Mg, Fe, and Ca, respectively, in the fresh weight of flowers. These results show that there is high variability between and within traditional edible flower species and that they are relevant sources of macro- and microelements for health, such as in the case of Fe and Zn, which are associated with malnutrition in vulnerable social groups when their intake is low.

In Oaxaca, Mexico, the consumption of the inflorescences of Yucca filifera Chabaud (‘izote’ in Spanish), Agave Salmiana Otto ex Salm-Dyck (‘maguey pulquero’), Diphysa americana (Mill.) M. Sousa (‘cuachepil’ or ‘guachepil’), and Chamaedorea tepejilote Liebm. (‘tepejilote’ or ‘pacaya’) is part of rural community food systems [35,36]. However, there is little information about the content of macro- and microelements in these edible flowers and their variation in the different regions where they are grown. Therefore, the objective of this study was to evaluate the variation in mineral content in the inflorescences of Y. filifera, A. salmiana, D. americana, and C. tepejilote from samples collected from different communities and regions of Oaxaca, Mexico.

2. Materials and Methods

2.1. Plant Material

Eleven population samples of izote (Yucca filifera Chabaud) inflorescences, 10 of maguey pulquero (Agave salmiana Otto ex Salm-Dyck), 11 of cuachepil (Diphysa americana (Mill.) M. Sousa), and 11 of tepejilote Chamaedorea tepejilote Liebm. (‘tepejilote’ or ‘pacaya’) from samples collected in different communities and regions) were collected in 26 communities distributed in the regions of Valles Centrales, Sierra Sur, Mixteca, and Papaloapan, Oaxaca, Mexico, from September 2021 to March 2022 (Figure 1). The different origins of the samples from each species were included to quantify the environmental and genetic variations (referred to as origin locations in the first table) that influenced the chemical composition of the plants and their reproductive organs, such as the flowers. The flowers were separated from the inflorescences to avoid physical damage, subsequently dried at room temperature, and finally dried by means of a food dryer at 45 °C, always in a cool, dry place without direct light. The samples were subsequently ground in an electric mill (Moongiantgo^® model HO-150, Seattle, WA, USA) for 30 s, sealed in labeled amber jars, and stored at −20 °C until analysis. The ecogeographic description of the origins of the inflorescence collection sites and communities as well as a distribution map were previously reported by Marcos-Gómez et al. [26] as the first part of the study. For taxonomic identification, all the species were corroborated by comparisons with specimens already preserved in the institutional herbarium (national key OAX-FLO-129-0402 and acronym OAX in the Index Herbariorum).

2.2. Sample Preparation and Mineral Content Evaluations

The ground samples of izote, agave, cuachepil, and tepejilote inflorescences were brought to constant weight at 100 °C (AACC 44-15) and incinerated at 580 °C in a muffle furnace (FELISA FE340, Jalisco, Mexico) for eight hours or until white ash and constant weight were obtained (AACC 08-01.01) [37]. To each ash sample, 2 mL of concentrated hydrochloric acid (JT Baker^®) was added, and the volume was brought to 50 mL with deionized water. The solution was filtered with fine-pore filter paper, and the collected sample was transferred to a bottle, which was sealed and stored under refrigeration until analysis. At the same time as the preparation of the analysis samples, a blank was prepared via the same procedure without a sample so that the possible effect of reagent contamination could be ruled out [38].

The evaluation and quantification of micro- and macroelements (Cu, Fe, Zn, Mn, Mo, Si, P, Ca, Mg, K, Na, and S) were performed via optical emission spectrometry with inductively coupled plasma (ICP-OES, Thermo Scientific iCAP 6500 DUO, Cambridge, UK) in the radial and axial configurations, with argon as the auxiliary gas and an autosampler (CETAC ASX-520, Omaha, NE, USA). The analysis was performed with an auxiliary gas flow at 0.4 L min⁻¹, 1200 W RF power, and 50 rpm analysis speed, with 10 s to stabilize the peristaltic pump. The quantification was performed on the basis of multielement reference standards (High Purity Standards^®, Charleston, SC, USA) of P, Mg, K, Ca, Fe, and Na in the ranges of 1 to 100 mg L⁻¹ and 0.2 to 5 µg mL⁻¹ for Cu, S, Mn, and Zn. The lower limits of detection for Mn, Cu, Zn, Mg, Na, and S were 0.0001, 0.0002, 0.002, 0.003, 0.005, and 0.009 mg L⁻¹, respectively, and 0.01 mg L⁻¹ for P, K, and Ca. All the analyses were performed in triplicate, and the results are expressed in mg 100 g⁻¹ dry weight sample (dw) [38].

2.3. Statistical Analysis

Using information on the contents of macroelements (P, Mg, K, Na, S, and Ca) and microelements (Cu, Mn, Mo, Si, Zn and Fe) in each sample, a database was formed, and an analysis of variances was performed with all the mineral contents through a completely random linear model for each species, including as sources of variation to origin locations and error effects, where the samples represented population patches or backyards where the inflorescences grew and developed or the community geographic origin (ID). When there were differences between sample origins, multiple comparisons of means were performed via the Tukey method (p < 0.05). Complementarily, a principal component analysis (PCA) was performed using means per sample for each species and was based on the methodology of PCA described by Olguín-Hernández et al. [39]. All the statistical analyses were performed via the SAS statistical package (version 9.0, SAS Institute Inc., Cary, NC, USA) [40].

3. Results

3.1. Minerals in Y. filifera Flowers

In the analysis of variance (ANOVA), significant differences (p < 0.01) were found between the macro- and microelements, except for the Na and Cu contents, as a function of the origin locations of the samples. For all the minerals evaluated except for Na, there was greater variance (=mean square) due to the effect of the origin location than due to the error effect (

Table 1. Significance of square means from the analysis of variance of micro- and macroelements in the inflorescences of Y. filifera, A. salmiana, D. americana, and C. tepejilote collected from different communities and regions in Oaxaca, Mexico.

Y. filifera (Izote):
Sources of Variation	Macroelements
	P	Mg	K	Na	S	Ca
Origin locations	41,482 **	7864.8 **	247,688 **	0.34 ns	1580 **	40,262 **
Error	29.5	4.7	1665.5	0.501	7.65	93.6
Coeff. of variation (%)	0.8	0.9	1.6	12.8	1.7	1.8
Sources of Variation	Microelements
	Cu	Mn	Mo	Si	Zn	Fe
Origin locations	14.11 ns	7.08 **	0.14 **	14.9 **	468.1 **	365.6 **
Error	6.15	0.11	0.002	1.84	0.61	7.00
Coeff. of variation (%)	24.2	3.1	9.7	13.0	1.5	7.1
A. salmiana (Maguey Pulquero):
Sources of Variation	Macroelements
	P	Mg	K	Na	S	Ca
Origin locations	38,899 **	11,697 **	328,080 **	0.41 ns	685.3 **	310,324 **
Error	16.6	3.86	2350.4	0.43	12.3	102.2
Coeff. of variation (%)	0.7	0.6	2.2	22.9	3.6	1.2
Sources of Variation	Microelements
	Cu	Mn	Mo	Si	Zn	Fe
Origin locations	6.9 **	91.2 **	0.34 **	498.7 ns	217.0 **	49.2 **
Error	0.103	0.068	0.018	226.3	1.71	3.81
Coeff. of variation (%)	4.4	1.6	2.5	26.5	2.92	6.3
D. americana (Cuachepil):
Sources of Variation	Macroelements
	P	Mg	K	Na	S	Ca
Origin locations	10,702 **	1595.5 **	1157.4 **	5.39 ns	2086.7 **	44,200 **
Error	42.3	6.32	15.6	3.04	14.9	49.2
Coeff. of variation (%)	1.1	0.8	1.7	21.3	2.4	1.6
Sources of Variation	Microelements
	Cu	Mn	Mo	Si	Zn	Fe
Origin locations	26.6 **	48.7 **	18.7 **	29.9 **	100.3 **	152.8 **
Error	3.03	0.05	0.019	1.09	0.54	1.76
Coeff. of variation (%)	14.0	1.2	3.2	11.2	1.6	2.6
C. tepejilote (Tepejilote):
Sources of Variation	Macroelements
	P	Mg	K	Na	S	Ca
Origin locations	20,002 **	112,073 **	282,853 **	1.41 ns	11,710 **	389,290 **
Error	34.6	52.3	3695.4	1.02	58.9	965.4
Coeff. of variation (%)	0.7	0.9	1.9	15.8	0.7	1.2
Sources of Variation	Microelements
	Cu	Mn	Mo	Si	Zn	Fe
Origin locations	1.09 ns	1511.5 **	ND	2652.2 **	136.9 **	702.5 **
Error	0.603	1.51	ND	24.1	4.4	15.1
Coeff. of variation (%)	18.6	1.5	ND	3.6	2.5	4.0

** significant at p ≤ 0.01; ^ns not significant (p > 0.05); ND, not determined or nondetectable content.

), which was part of the linear model of analysis and sources of variation in the ANOVA. All these results indicate that the greatest cause of the variation was due to the effect of sample origin or location rather than the effect of the interactions of samples and variations within samples or replicates.

In terms of the macroelement concentrations in Y. filifera, the relevant pattern among sample origins was that there was high variation and significant differences between and within samples with the same or different geographic community origins. For example, the samples of inflorescences collected from the backyards of Magdalena Jaltepec presented low values, but significant differences were distinguished concerning samples 02b and 02c, which presented high values of P, K, S, and Ca. In terms of the P content, the second highest value (764.9 mg 100 g⁻¹) corresponded to the sample collected from Santa Maria Sola in Sierra Sur, with the highest value of Mg (289.6 mg 100 g⁻¹). The samples from Santo Tomas Tamazulapam, Santa Ana Miahuatlan, and Ejutla de Crespo had high Mg concentrations (288.1 to 302.1 mg 100 g⁻¹), indicating differences between origins. Notably, there was high variability between the samples evaluated in terms of their concentrations of P, Mg, K, S, and Ca. In the case of Na, there were no significant differences between the samples, with values ranging from 4.8 to 20.5 mg 100 g⁻¹, and high variability was detected within each sample or different samples from the same community (

Table 2. Macro- and microelements in inflorescences of Y. filifera (izote) collected in different regions and communities from Oaxaca, Mexico.

Communitarian Origins of Samples (ID)	Macroelements (mg 100 g−1)
	P	Mg	K	Na	S	Ca
Magdalena Jaltepec-010	538.9 ± 3.4 g 1	212.4 ± 3.5 e	2237.5 ± 5.8 f	11.8 ± 6.6 a	144.5 ± 0.9 g	500.3 ± 15.9 e
Magdalena Jaltepec-01a	549.9 ± 2.1 fg	164.5 ± 0.7 h	2449.7 ± 12.5 e	8.6 ± 1.3 a	126.0 ± 2.2 h	467.9 ± 8.6 f
Magdalena Jaltepec-01b	588.9 ± 11.5 e	185.0 ± 3.1 g	2435.7± 42.4 e	4.8 ± 3.3 a	129.8 ± 0.1 h	678.3 ± 11.9 b
Magdalena Jaltepec-01c	465.7 ± 2.3 h	205.9 ± 2.9 f	2494.9 ± 12.2 de	12.4 ± 8.6 a	149.6 ± 1.2 fg	566.0 ± 3.8 d
Magdalena Jaltepec-02a	679.3 ± 3.1 d	184.0 ± 0.4 g	2614.2 ± 3.0 c	9.8 ± 1.6 a	160.7 ± 3.3 de	636.4 ± 4.2c
Magdalena Jaltepec-02b	736.9 ± 6.3 c	238.4 ± 1.2 d	3129.7 ± 40.6 a	12.4 ± 0.4 a	181.2 ± 4.0 b	521.8 ± 5.6 e
Magdalena Jaltepec-02c	869.0 ± 4.0 a	249.7 ± 1.7 c	2879.9 ± 48.6 b	19.6 ± 13.4 a	206.1 ± 1.6 a	730.5 ± 3.1 a
Santo Tomas Tamazulapan	671.5 ± 4.2 d	288.1 ± 2.1 b	2488.0 ± 44.3 de	9.6 ± 0.2 a	170.5 ± 3.0 c	394.2 ± 6.0 g
Santa Maria Sola	764.9 ± 2.6 b	289.6 ± 1.2 b	2594.8 ± 64.9 cd	20.5 ± 20.5 a	157.2 ± 3.9 ef	388.6 ± 7.9 g
Santa Ana Miahuatlan	559.1 ± 5.5 f	302.1 ± 1.6 a	2075.8 ± 72.1 g	5.5 ± 2.8 a	148.7 ± 2.0 g	496.0 ± 16.9 ef
Ejutla de Crespo	666.5 ± 6.4 d	301.0 ± 3.5 a	2699.4 ± 28.6 c	13.0 ± 6.4 a	167.5 ± 3.6 cd	407.0 ± 8.4 g
Communitarian Origins of Samples (ID)	Microelements (mg 100 g−1)
	Cu	Mn	Si	Zn	Fe	Mo
Magdalena Jaltepec-010	0.86 ± 0.24 a 1	1.15 ± 0.06 bc	9.41 ± 3.48 bc	3.94 ± 0.04 g	2.89 ± 0.32 de	0.05 ± 0.0 cd
Magdalena Jaltepec-01a	1.00 ± 0.55 a	0.92 ± 0.03 d	5.50 ± 0.77 c	3.75 ± 0.05 g	2.41 ± 0.34 e	0.04 ± 0.0 c–e
Magdalena Jaltepec-01b	0.74 ± 0.13 a	0.81 ± 0.02 e	9.38 ± 3.24 bc	3.73 ± 0.07 g	2.72 ± 0.13 de	0.06 ± 0.0 bc
Magdalena Jaltepec-01c	0.77 ± 0.12 a	1.16 ± 0.06 a–c	14.01 ± 4.65 b	4.67 ± 0.16 e	3.30 ± 0.62 b–d	0.05 ± 0.0 c
Magdalena Jaltepec-02a	1.39 ± 0.34 a	0.81 ± 0.01 e	9.73 ± 1.44 bc	4.33 ± 0.12 f	3.18 ± 0.04 cd	0.03 ± 0.0 f
Magdalena Jaltepec-02b	1.24 ± 0.25 a	1.13 ± 0.01 bc	11.59 ± 2.80 bc	5.15 ± 0.04 d	3.94 ± 0.05 bc	0.03 ± 0.0 d–f
Magdalena Jaltepec-02c	1.13 ± 0.06 a	1.21 ± 0.02 ab	7.45 ± 2.77 bc	7.07 ± 0.04 a	4.04 ± 0.14 b	0.03 ± 0.0 ef
Santo Tomas Tamazulapan	1.20 ± 0.32 a	1.25 ± 0.00 a	24.38 ± 1.95 a	5.59 ± 0.04 c	ND	0.07 ± 0.0 b
Santa Maria Sola	1.16 ± 0.02 a	1.09 ± 0.00 c	13.11 ± 3.08 bc	6.24 ± 0.01 b	5.60 ± 1.10 a	0.10 ± 0.0 a
Santa Ana Miahuatlan	0.80 ± 0.03 a	0.97 ± 0.03 d	7.17 ± 0.77 bc	5.61 ± 0.00 c	3.74 ± 0.16 bc	0.03 ± 0.2 ef
Ejutla de Crespo	0.98 ± 0.03 a	1.08 ± 0.03 c	14.07 ± 3.77 b	7.14 ± 0.07 a	5.57 ± 0.09 a	0.04 ± 0.0 d–f

¹ in columns, the means of macro- and microelements with the same letter are not significantly different (Tukey’s test, p ≤ 0.05); ND = level not detected.

).

In terms of the microelement content, significant differences and high variability were observed between samples with different geographical origins. In the case of Mn, the samples with lower values (0.81 mg 100 g⁻¹) were collected from Magdalena Jaltepec-01b and -02a, but the samples with high values also originated from the same community (010, 01c, 02b, and 02c) and from Santo Tomas Tamazulapan (1.13 to 1.25 mg 100 g⁻¹). This pattern was repeated for Si, Zn, Fe, and Mo, for which high values were present in the samples from Santo Tomas, Magdalena Jaltepec-02c, Santa Maria Sola, and Ejutla de Crespo. On the other hand, low values of Zn and Fe were detected in the samples from Magdalena Jaltepec-010, -01a, and -01b (Table 2). In summary, the results differed from one community to another and between samples from the same community, with differences associated with each plant growth microenvironment.

3.2. Minerals in A. salmiana Flowers

In the analysis of variance of the mineral macro- and micronutrient contents, significant differences (p < 0.01) were detected among all the elements evaluated, except Na and Si. For all the minerals analyzed except Na, the variance magnitude or square means due to the effect of the community origin of the collection evaluated were greater than the variance of the error effect (named “origin locations” and “error” in Table 1). Additionally, high variability within samples was observed in terms of the Na and Si contents.

The content of mineral macroelements in the flowers of A. salmiana showed high and significant variability according to the community origins of the samples (

Table 3. Macro- and microelements in inflorescences of A. salmiana (agave pulquero) collected in different regions and communities from Oaxaca, Mexico.

Communitarian Origins of Samples (ID)	Macroelements (mg 100 g−1)
	P	Mg	K	Na	S	Ca
San Esteban Atatlahuca	462.2 ± 2.0 h 1	303.3 ± 1.7 f	2075.7 ± 16.5 d	4.7 ± 2.2 a	92.2 ± 3.4 c	989.4 ± 7.4 c
San Pedro Molinos	608.5 ± 0.5 c	324.0 ± 1.9 d	2237.6 ± 6.7 c	1.6 ± 0.01 a	88.5 ± 6.6 cd	723.0 ± 7.8 d
San Jose Monte Verde	530.4 ± 4.0 e	345.7 ± 1.1 c	2358.3 ± 111.5 bc	44.7 ± 0.01 a	113.4 ± 3.4 b	647.7 ± 8.2 ef
Santa Cruz Nundaco	689.6 ± 1.5 b	363.5 ± 2.6 b	2430.6 ± 22.7 b	6.1 ± 3.1 a	91.2 ± 3.4 c	633.1 ± 9.4 f
Chalcatongo de Hidalgo	745.9 ± 3.3 a	433.6 ± 2.8 a	2731.0 ± 20.8 a	10.6 ± 2.3 a	104.9 ± 3.2 b	1416.3 ± 18.8 a
Santo Tomas Ocotepec	354.8 ± 6.9 i	233.1 ± 2.0 h	1844.5 ± 28.3 e	6.3 ± 1.8 a	90.5 ± 2.8 c	419.6 ± 6.2 h
San Juan Teposcolula	481.6 ± 6.3 g	221.7 ± 2.4 i	1815.7 ± 84.6 e	19.4 ± 22.4 a	79.7 ± 2.1 de	472.1 ± 11.4 g
San Pedro Tidaa	599.4 ± 0.8 cd	268.2 ± 1.4 g	2623.6 ± 11.9 a	1.9 ± 0.01 a	123.9 ± 2.6 a	1006.4 ± 8.1 c
Santa Lucia Monte Verde	590.4 ± 4.3 d	310.8 ± 1.9 e	2030.1 ± 40.8 d	5.2 ± 0.5 a	107.0 ± 3.3 b	1185.6 ± 5.9 b
Santa Cruz Itundujia	516.6 ± 4.6 f	308.1 ± 0.7 ef	1846.8 ± 5.5 e	10.5 ± 3.5 a	76.2 ± 2.0 e	668.5 ± 11.2 e
Communitarian Origins of Samples (ID)	Microelements (mg 100 g−1)
	Cu	Mn	Mo	Si	Zn	Fe
San Esteban Atatlahuca	0.64 ± 0.03 ef 1	2.25 ± 0.01 b	0.052 ± 0.01 d	4.45 ± 1.56 a	3.65 ± 0.06 e	2.83 ± 0.22 c
San Pedro Molinos	0.57 ± 0.0 fg	2.20 ± 0.03 b	0.052 ± 0.01 d	4.67 ± 0.63 a	4.20 ± 0.03 cd	2.75 ± 0.13 c
San Jose Monte Verde	0.87 ± 0.0 b	1.25 ± 0.03 f	0.103 ± 0.01 b	6.17 ± 0.97 a	4.40 ± 0.28 bc	2.80 ± 0.03 c
Santa Cruz Nundaco	0.57 ± 0.0 fg	1.82 ± 0.05 c	0.052 ± 0.01 d	6.95 ± 1.35 a	5.64 ± 0.08 a	3.40 ± 0.16 b
Chalcatongo de Hidalgo	0.99 ± 0.06 a	2.54 ± 0.01 a	0.053 ± 0.01 c	5.11 ± 0.58 a	4.39 ± 0.10 bc	3.16 ± 0.24 bc
Santo Tomas Ocotepec	0.81 ± 0.06 bc	1.09 ± 0.01 g	0.052 ± 0.01 d	7.81 ± 3.91 a	3.08 ± 0.12 f	3.27 ± 0.17 bc
San Juan Teposcolula	0.52 ± 0.01 g	1.09 ± 0.01 g	0.052 ± 0.01 d	5.55 ± 0.92 a	3.86 ± 0.17 de	2.88 ± 0.26 bc
San Pedro Tidaa	0.83 ± 0.01 bc	1.51 ± 0.01 d	0.100 ± 0.01 a	4.52 ± 0.50 a	4.63 ± 0.05 b	2.81 ± 0.14 c
Santa Lucia Monte Verde	0.71 ± 0.03 de	1.04 ± 0.01 g	0.052 ± 0.01 d	4.29 ± 0.37 a	5.65 ± 0.11 a	2.99 ± 0.12 bc
Santa Cruz Itundujia	0.75 ± 0.03 cd	1.36 ± 0.05 e	ND	7.23 ± 0.35 a	5.30 ± 0.11 a	4.06 ± 0.32 a

¹ in columns, the means of macro- and microelements with the same letter are not significantly different (Tukey’s test, p ≤ 0.05); ND = level not detected.

). That is, patterns of low and high concentrations were observed; for example, the samples collected from communities from Santo Tomas Ocotepec, San Juan Teposcolula, Santa Cruz Itundujia, and San Esteban Atatlahuca presented low values of P, Mg, K, S, and Ca. In contrast, the samples from Santa Cruz Nundaco and Chalcatongo de Hidalgo presented high values of P, Mg, and K, a pattern that was repeated in those collected in San Pedro Tidaa, Santa Lucia Monte Verde, and Chalcatongo with respect to S and Ca. In this analysis, the Na concentrations of the samples were not significantly different on the basis of origin, with variations from 1.6 to 44.7 mg 100 g⁻¹. The mineral macronutrient composition was highly variable in terms of Mg, S, K, Ca, and P among the samples, and the highest concentrations of K, Ca, and P in all the evaluated samples were obtained from these samples. This wide variability and significant differences between sample origins are indicators of environmental effects, but the effects of genetic–environmental interactions cannot be ruled out.

In health, microelements play relevant roles in metabolic processes and enzyme systems. The samples of A. salmiana showed high variability between groups of minerals, or one or more samples did not show consistently high or low values from one element to another, except for the samples from San Juan Teposcolula. For example, the inflorescences collected from San Esteban Atatlahuca and San Pedro Molinos presented low values of Cu, Mo, Zn, and Fe but high values of Mn. In the case of the San Juan Teposcolula sample, the contents of all the elements were consistently low. Another group of elements relevant to health includes Zn and Fe, for which the samples from Santa Cruz Nundaco, Santa Lucia Monte Verde, and Santa Cruz Itundujia presented high values. The variation in concentrations of microelements is an indicator of high microenvironmental variability in the conditions of plant growth and development of the flower scapes and inflorescences of A. salmiana, a plant that regularly spreads asexually without anthropogenic help (Table 3).

3.3. Minerals in D. americana Flowers

In the analysis of variance of the contents of macro- and microelements, significant differences (p ≤ 0.01) were detected for all the elements except for Na based on the origin of the samples of D. americana. The variances (=mean squares) estimated on the basis of the origin of the samples were significantly greater than the variance attributed to the error effect (Table 1). This pattern suggests that the concentrations of minerals in the samples are strongly affected by the environment and genetic–microenvironmental interactions.

In the comparison of the micromineral contents in the D. americana inflorescence samples from different geographical origins, significant differences were detected between and within locations or origins. For example, the samples collected in Santa Cruz Xitla presented high P, Mg, and S contents, but those from Agua Fria Sola de Vega-1 and Santa Lucia Miahuatlan presented low values. In contrast, the Agua Fria Sola sample from Sola de Vega-2 presented high values of Mg but low values of P, K, S, and Ca and differed from the pattern recorded for the sample collected in San Pedro El Alto, which was high in S but low in P, Mg, K, and Ca. These different patterns indicate that the effect of the microniche where the plants developed was due to the edaphoclimatic conditions of the site and genetic–biological–environmental interactions. This pattern of variation changed from element to element, as observed for P, Mg, K, S, and Ca (

Table 4. Contents of macro- and microelements in inflorescences of D. americana (cuachepil) collected from different regions and communities in Oaxaca, Mexico.

Community Origins of Samples (ID)	Macroelements (mg 100 g−1)
	P	Mg	K	Na	S	Ca
San Andres Paxtlan	505.6 ± 0.9 g 1	331.5 ± 0.8 b	246.1 ± 1.0 b–d	7.7 ± 4.5 a	152.6 ± 1.3 c	576.7 ± 3.1 b
San Felipe Zapotitlan	521.9 ± 2.2 g	259.4 ± 0.6 g	199.1 ± 0.5 h	1.3 ± 0.01a	148.7 ± 3.0 c	608.8 ± 1.7a
Santa Cruz Xitla-1	702.1 ± 12.1 a	346.2 ± 5.8 a	235.4 ± 4.6 d–f	8.2 ± 1.7 a	169.4 ± 8.5 b	354.1 ± 1.9 f
Santa Cruz Xitla-2	633.9 ± 14.4 b	317.3 ± 2.1 c	250.2 ± 9.6 a–c	7.0 ± 4.9 a	142.9 ± 6.7 c	581.2 ± 3.8 b
Santa Cruz Xitla-3	623.3 ± 6.7 bc	306.5 ± 3.2 d	256.1 ± 3.6 ab	3.8 ± 3.3 a	168.1 ± 1.3 b	407.8 ± 5.2 e
Agua Fria Sola de Vega-1	597.6 ± 4.6 de	298.9 ± 2.4 ef	204.4 ± 0.3 h	5.0 ± 0.3 a	144.0 ± 1.2 c	396.9 ± 2.9 e
Agua Fria Sola de Vega-2	551.4 ± 2.4 f	325.4 ± 1.2 b	230.0 ± 1.9 fg	6.1 ± 2.4 a	130.3 ± 1.3 d	243.6 ± 14.3 h
Reyes Sola de Vega-1	605.3 ± 4.0 cd	305.2 ± 1.8 de	221.0 ± 2.4 g	5.8 ± 5.4 a	203.1 ± 4.0 a	305.0 ± 13.9 g
Reyes Sola de Vega-2	605.4 ± 3.2 cd	326.5 ± 2.0 b	258.9 ± 1.7 a	5.6 ± 1.2 a	177.0 ± 1.9 b	509.3 ± 4.8 c
San Pedro El Alto	584.6 ± 1.6 e	295.1 ± 2.1 f	242.0 ± 5.2 c–e	5.4 ± 1.3 a	204.6 ± 1.7 a	346.4 ± 5.5 f
Santa Lucia Miahuatlan	509.6 ± 2.9 g	303.9 ± 1.0 de	234.1 ± 2.0 ef	3.4 ± 0.4 a	127.4 ± 2.9 d	439.8 ± 4.5 d
Community Origins of Samples (ID)	Microelements (mg 100 g−1)
	Cu	Mn	Mo	Si	Zn	Fe
San Andres Paxtlan	1.02 ± 0.08 bc 1	2.22 ± 0.01 c	0.55 ± 0.03 d	11.53 ± 2.18 b	4.52 ± 0.03 cd	5.44 ± 0.13 b
San Felipe Zapotitlan	1.24 ± 0.11 ab	2.04 ± 0.01 d	ND	15.30 ± 2.28 a	3.77 ± 0.06 g	4.65 ± 0.03 e
Santa Cruz Xitla-1	0.57 ± 0.23 c	1.66 ± 0.03 f	0.37 ± 0.01 f	7.35 ± 0.09 cd	4.41 ± 0.10 c–e	5.23 ± 0.20 bc
Santa Cruz Xitla-2	1.59 ± 0.27 a	2.03 ± 0.03 d	0.65 ± 0.03 c	12.40 ± 0.20 ab	5.07 ± 0.14 b	6.31 ± 0.25 a
Santa Cruz Xitla-3	1.08 ± 0.03 bc	2.50 ± 0.05 a	0.313± 0.01 g	6.99 ± 0.23 de	5.44 ± 0.03 a	3.96 ± 0.13 f
Agua Fria Sola de Vega-1	1.32 ± 0.03 ab	1.57 ± 0.0 g	0.052 ± 0.01 h	11.41 ± 0.43 b	4.07 ± 0.06 f	5.41 ± 0.14 bc
Agua Fria Sola de Vega-2	1.53 ± 0.16 ab	2.34 ± 0.03 b	0.051 ± 0.01 h	7.05 ± 0.12 de	4.57 ± 0.06 c	4.57 ± 0.10 e
Reyes Sola de Vega-1	1.48 ± 0.11 ab	1.31 ± 0.03 i	0.692 ± 0.01 b	8.13 ± 1.03 cd	5.31 ± 0.11 a	5.04 ± 0.03 cd
Reyes Sola de Vega-2	1.53 ± 0.37 ab	2.36 ± 0.01 b	0.421 ± 0.01 e	7.60 ± 0.61 cd	5.45 ± 0.04 a	4.75 ± 0.04 de
San Pedro El Alto	1.08 ± 0.06 a–c	1.78 ± 0.01 e	0.366 ± 0.01 f	4.27 ± 0.13 e	4.31 ± 0.03 de	4.78 ± 0.03 de
Santa Lucia Miahuatlan	1.24 ± 0.08 ab	1.45 ± 0.01 h	0.780 ± 0.01 a	10.34 ± 0.53 bc	4.25 ± 0.02 ef	6.29 ± 0.13 a

¹ in columns, the means of macro- and microelements with the same letter are not significantly different (Tukey’s test, p ≤ 0.05); ND = level not detected.

).

The content of mineral microelements in the inflorescences of D. americana showed highly variable patterns and significant differences between and within geographic locations. For example, for Cu, the samples from Agua Fria and Reyes de Sola de Vega, San Pedro El Alto, Santa Lucia Miahuatlan, Santa Cruz Xitla-2, and San Felipe Zapotitlan did not differ significantly, except with respect to Santa Cruz Xitla-1, which also presented low values of Mn, Mo, Si, and Zn. In terms of Mn, the samples from Santa Cruz Xitla-1, Agua Fria-2, and Reyes, Sola de Vega-2 showed significant differences with respect to their counterparts from the same localities, Santa Cruz Xitla-1, Agua Fria-1, and Reyes Sola de Vega-1, respectively, indicating that within the same locality, there are microniches that significantly affect the contents of microelements, a pattern that is repeated in terms of the concentrations of Si, Zn, and Fe. Notably, the sample from Santa Cruz Xitla-2 presented high values of Zn and Fe deficiencies which are associated with malnutrition (Table 4).

3.4. Minerals in C. tepejilote Flowers

In the analysis of variance of the macro- and microelement contents, significant differences (p < 0.01) were found for all the elements evaluated except for Na and Cu in terms of the geographical origins of the samples. As in previous cases, the variance due to the effect of origin location was greater than the variance due to the error effect, indicating that tropical microniches significantly influenced the mineral content and genetic-environmental effects (Table 1).

In the comparison of macroelement contents as a function of sampling location, significant differences were observed between and within geographic origins. In this case, differences were found among multiple samples collected from San Felipe Jalapa de Diaz, Ayotzintepec, and Santa Maria Jacatepec. The inflorescences collected in San Felipe Jalapa de Diaz presented high values of P, Mg, S, and Ca, in contrast with the samples from Ayotzintepec and Santa Maria Jacatepec-1 and -2, which presented low values of the same elements. The Valle Nacional sample exhibited a high Mg content, and the Santa Maria Jacatepec-3 and Santiago Jocotepec samples exhibited high K contents, an element relevant to health. K and Ca were the most abundant minerals, and in the case of Na, the samples did not differ significantly (

Table 5. Variation in macro- and microelements in inflorescences of C. tepejilote collected from different regions and communities in Oaxaca, Mexico.

Communitarian Origins of Samples (ID)	Macroelements (mg 100 g−1)
	P	Mg	K	Na	S	Ca
Sn. Juan Bta. Valle Nacional	775.3 ± 5.8 g 1	842.7 ± 3.0 b	2853.3 ± 42.3 f	15.47 ± 9.2 a	1094.4 ± 12.8 bc	2586.1 ± 24.0 e
Sn. Fpe. Jalapa de Diaz-1	941.7 ± 4.3 a	852.2 ± 2.5 b	2802.6 ± 20.4 f	20.57 ± 4.9 a	1108.0 ± 9.3 b	3088.6 ± 17.7 b
Sn. Fpe. Jalapa de Diaz-2	909.3 ± 2.9 b	801.8 ± 5.3 c	2813.4 ± 9.3 f	17.00 ± 8.9 a	1112.2 ± 5.0 b	2915.2 ± 13.3 c
Sn. Fpe. Jalapa de Diaz-3	882.8 ± 2.2 c	771.7 ± 11.1 d	2940.6 ± 36.9 f	22.50 ± 9.4 a	1142.9 ± 8.8 a	2812.2 ± 52.2 d
Ayotzintepec-1	808.2 ± 9.2 e	811.3 ± 12.2 c	3431.5 ± 167.5 bc	43.67 ± 41.7 a	959.4 ± 1.0 f	2387.1 ± 35.7 fg
Ayotzintepec-2	781.4 ± 7.9 fg	730.8 ± 9.0 e	3221.9 ± 40.2 de	28.17 ± 4.1 a	1066.1 ± 9.6 de	2263.1 ± 41.9 h
Ayotzintepec-3	842.6 ± 7.7 d	738.1 ± 3.3 e	3226.0 ± 41.9 de	20.47 ± 13.2 a	1075.6 ± 5.4 cd	2303.3 ± 15.7 gh
Santa Maria Jacatepec-1	752.0 ± 0.7 h	533.1 ± 5.9 h	3167.6 ± 13.6 e	9.95 ± 1.2 a	1045.2 ± 4.6 e	2358.7 ± 22.4 g
Santa Maria Jacatepec-2	796.6 ± 7.0 ef	595.3 ± 10.6 g	3398.6 ± 23.7 cd	13.60 ± 11.4 a	1054.3 ± 8.2 de	2474.2 ± 46.6 f
Santa Maria Jacatepec-3	643.8 ± 1.4 i	1281.0 ± 3.7 a	3588.5 ± 54.3 ab	20.87 ± 9.0 a	945.7 ± 3.7 f	3383.7 ± 23.9 a
Santiago Jocotepec	808.2 ± 7.5 e	667.0 ± 0.8 f	3650.3 ± 43.3 a	30.40 ± 3.7 a	1110.0 ± 8.3 b	2771.8 ± 18.0 d
Communitarian Origins of Samples (ID)	Microelements (mg 100 g−1)
	Cu	Mn	Si	Zn	Fe
San Juan Bta. Valle Nacional	1.40 ± 0.01 a 1	13.65 ± 0.18 a	141.3 ± 8.9 c	8.83 ± 0.30 a	8.32 ± 0.63 ef
San Fpe. Jalapa de Diaz-1	1.43 ± 0.09 a	8.67 ± 0.09 d	161.4 ± 4.8 b	9.20 ± 0.34 a	9.24 ± 0.07 c–f
San Fpe. Jalapa de Diaz-2	1.43 ± 0.09 a	9.21 ± 0.12 c	136.2 ± 3.1 cd	8.95 ± 0.14 a	9.28 ± 0.20 c–e
San Fpe. Jalapa de Diaz-3	3.09 ± 2.48 a	6.25 ± 0.05 hi	122.7 ± 4.8 de	8.11 ± 0.24 b	9.46 ± 0.39 b–d
Ayotzintepec-1	2.34 ± 0.94 a	6.52 ± 0.03 gh	104.1 ± 5.4 f	8.11 ± 0.13 b	9.83 ± 0.52 bc
Ayotzintepec-2	2.03 ± 0.96 a	6.63 ± 0.18 g	102.7 ± 1.7 f	7.71 ± 0.23 bc	8.50 ± 0.25 d–f
Ayotzintepec-3	2.42 ± 0.08 a	7.36 ± 0.18 f	106.8 ± 3.1 f	9.11 ± 0.17 a	10.51 ± 0.31 b
Santa Maria Jacatepec-1	1.76 ± 0.29 a	6.50 ± 0.12 gh	121.7 ± 2.4 e	7.27 ± 0.17 c	8.12 ± 0.32 f
Santa Maria Jacatepec-2	1.48 ± 0.09 a	8.13 ± 0.11 e	126.5 ± 7.3 de	7.94 ± 0.13 b	9.96 ± 0.60 bc
Santa Maria Jacatepec-3	1.10 ± 0.09 a	9.79 ± 0.11 b	201.0 ± 1.4 a	8.84 ± 0.18 a	13.67 ± 0.05 a
Santiago Jocotepec	1.52 ± 0.05 a	6.11 ± 0.04 i	158.5 ± 4.0 b	9.23 ± 0.18 a	8.84 ± 0.41 c–f

¹ in columns, the means of macro- and microelements with the same letter are not significantly different (Tukey’s test, p ≤ 0.05).

).

A comparison of the contents of mineral microelements in the flowers of C. tepejilote revealed that there were no significant differences in the Cu contents among the sampling locations; however, for Mn, Si, and Zn, the samples collected in Valle Nacional, Jalapa de Diaz-1 and -2, and Santa Maria Jacatepec-3 presented high values that differed significantly from the low values reported for the samples from Jalapa de Diaz-3, Ayotzintepec-1 and -2, and Santa Maria Jacatepec-2 and -3. For Fe, the samples from Ayotzintepec-1 and -3 and Santa Maria Jactepec-2 and -3 exhibited high values, and the samples from Valle Nacional, Ayotzintepec-2, Santa Maria Jacatepec-1, and Santiago Jocotepec exhibited low values (Table 5).

Principal component analysis (PCA) revealed differences in mineral element contents between the evaluated species; A. salmiana and Y. filifera presented a certain degree of closeness, but C. tepejilote and D. americana did not. On the basis of the magnitude of the eigenvectors of the PCA, the first principal component (PC1) was associated positively with the K, Ca, Si, S, Mg and P concentrations, with eigenvector values ranging from 0.041 to 0.683, and the second principal component (PC2) was related mainly to Ca, Si, S, Mg and P, with values ranging from 0.032 to 0.506, but negatively to K (−0.727). The other mineral elements showed less influence and lower values of eigenvectors, and 98.1% of the total variance was explained by the two main principal components (Figure 2).

4. Discussion

Flowers have been consumed by ancient civilizations up to modern times in Asia, Europe, India, the Middle East, and the pre-Columbian cultures of Mesoamerica that settled in Mexico, where the tradition continues among the current indigenous groups of Oaxaca [1,41,42]. For example, the flowers of Y. filifera are consumed by the Mixtecos and Zapotecos indigenous groups; various species of Agave sp. are consumed by Cuicatecos, Mazatecos, Chinantecos, Zapotecos, Mixes, and Mixtecos; D. americana is consumed by Zapotecos and Chatinos; and inflorescences of C. tepejilote are collected, sometimes cultivated, and consumed by Chinantecos and Zapotecos from the Papaloapan region, all within the territory of Oaxaca, Mexico, and all are part of the traditional cuisine.

For the inflorescences of Y. filifera, the macroelement concentrations from highest to lowest were K > P > Ca > Mg > S across all the samples collected from different geographic origins. In general, K, Ca, P, and Mg represent the macroelements with the highest recommended intake values [43]. In this work, the samples with the highest Ca concentrations were from Magdalena Jaltepec-01b and -02c (678.3 to 730.5 mg 100 g⁻¹). The samples with the most P were collected from Magdalena Jaltepec-02c (869.0 mg 100 g⁻¹) and Santa Maria Sola (764.9 mg 100 g⁻¹), and the samples with the most Mg corresponded to Santa Ana Miahuatlan and Ejutla de Crespo (301.0 to 302.1 mg 100 g⁻¹). This finding indicates that Y. filifera can contribute these elements to the human diet, with intakes of 1000 to 1200, 700 to 1250, and 310 to 420 mg per day of Ca, P, and Mg, respectively. In terms of the recommendations for adults [43], the consumption of 100 g of dried flowers contributes 32% to 61% of Ca, 37% to 69% of P, and 39.0% to 72% of Mg. The values estimated here for Mg and Ca are higher than those reported by Nicknezhad et al. [34] (2.51 and 14.16 mg 100 g⁻¹ of Mg and Ca in Yucca gloriosa, respectively), and are within the ranges of Ca, higher in P and lower in Mg than the values recorded by Román-Cortés et al. [2] in five native Mexican leaf quelites. This pattern of similarities and differences is also observed when comparing the responses obtained here for Ca, P, and Mg with the results of Morales De León et al. [44] for Y. guatemalensis and Y. aloifolia L.

The variation in K content between samples with different geographical origins ranged from 2075.8 to 3129.7 mg 100 g⁻¹, indicating that these inflorescences of Y. filifera are a potential source of this element since the K daily intake recommendations are approximately 4700 mg per day for an adult individual [43], in contrast with other groups of species of leaf quelites. For example, in fifteen species of Amaranthus, Jiménez-Aguilark, and Grusak [45] obtained concentrations of 460 to 920 mg 100 g⁻¹, and in five species of leaf quelites (purslane, romerito, quintonil, quelite, and huauzontle) [2], the concentrations varied from 279.0 to 1862.3 mg 100 g⁻¹ for K. In other species of ornamental flowers (e.g., rose, begonia, chrysanthemum, and marigold) used as food, Rop et al. [7] reported variations from 196.73 to 380.87 mg 100 g⁻¹. The analyses presented here indicate that the differences between samples from different locations are due to strong environmental influences, soil characteristics, and interactions with genetic effects, which are factors that we recommend for exploration with greater precision in future studies.

For the inflorescences of Y. filifera, the micromineral concentrations from highest to lowest were Si > Zn > Fe > Mn > Cu > Mo, with significant differences between and within the samples according to geographical origin. Notably, in this work, there were no significant differences in the Cu contents (0.80 to 1.39 mg 100 g⁻¹) of the samples. Some of the most needed microelements are Fe, Zn, and Mn, and in this study, the recorded variations ranged from 2.41 to 5.60, 3.73 to 7.14, and 0.81 to 1.25 mg 100 g⁻¹, respectively. For Y. gloriosa, Nicknezhad et al. [34] estimated average concentrations of 2.54 and 0.27 mg 100 g⁻¹ for Fe and Zn, respectively; these values coincide with the Fe contents recorded in this work but differ substantially from the Zn concentrations. The values of Fe and Zn reported by Román-Cortés et al. [2] in leaf quelites were similar for Fe (3.3 to 9.3 mg 100 g⁻¹) but higher for Zn (0.5 to 3.3 mg 100 g⁻¹). These results indicate that the inflorescences of Y. filifera are a source of microelements that can complement or support the adult daily intake needs of Zn (8–11 mg), Mn (1.8 to 2.3 mg), and Fe (8–18 mg) [43]. However, it is necessary to specify the edaphoclimatic effects, genotypic effects, and growing seasons of the inflorescences because all these factors influence mineral composition. An additional element of the food described here is Si, with estimated variations in the samples ranging from 5.50 to 24.38 mg 100 g⁻¹, which potentially contributes to the adult food requirements of 30 mg Si per day; notably, few foods have significant quantities of this element.

‘Cacayas’, ‘gualumbos’, ‘patas de gallina de cerro’, or maguey (A. salmiana) inflorescences appear after eight to thirteen years of plant growth once the floral scape is emitted, although they may appear earlier due to stress effects on the plant. In this work, inflorescences of pulquero maguey were evaluated, but almost all the Agave species were consumed by the community. In Oaxaca, Mexico, the consumption of flowers of mezcal agaves such as A. angustifolia, A. potatorum, A. americana, A. rhodacantha, and A. marmorata was recorded, where the inflorescences are usually cut and the individual flowers are manually extracted to prepare a local or regional dish.

In the macromineral evaluations of the flowers of A. salmiana, the following relationships were determined: K > Ca ≥ P > Mg > S > Na. In this work, there were no significant differences in the Na contents of the samples on the basis of their geographical origins (1.9 to 44.7 mg 100 g⁻¹), perhaps because of the high variability within the samples of the same origin. For the inflorescences of A. salmiana de Hidalgo, Mexico, Pinedo-Espinoza et al. [46] reported the following relationship: K > P > Ca > Mg. When both works are compared, differences are observed; for example, variations in the K, Ca, P, and Mg contents from 1815.7 to 2731.0, 472.1 to 1416.3, 354.8 to 745.9, and 221.7 to 433.6 mg 100 g⁻¹, respectively, were found in our work compared with the values reported by these authors, 1600 > 320 > 220 > 120 mg 100 g⁻¹, with the same order of elements. Similarly, the values reported by Mulík and Ozuna [35] for A. americana L. were 1552.8, 361.2, 240.1, and 396.5 mg 100 g⁻¹ for the same list of elements. In A. atrovirens Karw ex Salm-Dyck, Morales De León et al. [44] reported concentrations of 27.0 and 114.0 mg 100 g⁻¹ for P and Ca, respectively. These differences and similarities in concentration patterns among the samples of inflorescences of Agave species indicate that despite the differences and variability in the influence of the environment, these flowers are a source of macroelements for supplementing or complementing the daily diet. However, one of the limitations of this food is that it is not frequently found in local or regional markets because it depends on seasonality and the number of plants per patch, and there is also no generalized food culture of frequent consumption.

The following relationships were determined for the concentrations of microelements in the inflorescences of A. salmiana: Si > Zn > Fe > Mn > Cu > Mo. In accordance with nutritional recommendations, the most needed microelements are Fe, Zn, Cu, and Mn. In this work, the variation between samples of different geographical origins ranged from 2.75 to 4.06, 3.08 to 5.64, 0.52 to 0.99, and 1.09 to 2.54 mg 100 g⁻¹, respectively; for A. salmiana, Pinedo-Espinoza et al. [46] reported values of 8.66, 4.66, 0.65, and 2.94 mg 100 g⁻¹; and for A. americana, Mulík and Ozuna [35] reported values of 7.7, 4.9, 0.3, and 1.1 mg 100 g⁻¹ for the same list of elements. The concentrations of Fe reported by Mapes and Basurto [1] for A. salmiana and Morales De León et al. [44] for A. atrovirens were 8.92 and 0.90 mg 100 g⁻¹, respectively. These reports reveal high variability in the concentrations of each micromineral due to growth conditions and probable differences between and within species and/or genotypes; however, the ontogenetic effect and metabolic capacity of extraction, translocation, and accumulation in plants under different stress conditions to which the plants are exposed annually for the production of the floral scape cannot be ruled out.

The yellow inflorescences and flowers of D. americana give a special color to the backyards of houses or roadsides, where they usually grow naturally or are planted. From December to the first months of the year, these flowers are marketed in almost all the traditional markets of Valles Centrales and Sierra Sur of Oaxaca, Mexico, where they compete regionally for sale or consumption with runner bean or ayocote flowers (Phaseolus coccineus L.). Owing to their attractive characteristics and aroma, the inflorescences are thought to contain many bioactive compounds [26], but they are only consumed by families with traditional local food cultures in the region of Oaxaca and southern Mexico.

The results revealed significant differences in macroelements in the D. americana samples from different geographic locations, and the macroelements were ordered from highest to lowest as P > Ca > Mg > K > S > Na, varying from 505.6 to 702.1, 243.6 to 608.0, 259.4 to 346.2, 199.1 to 258.9, 130.3 to 203.1, and 1.3 to 7.7 mg 100 g⁻¹, respectively. Pascual-Mendoza et al. [31] compared the macroelement contents of eight species of leaf quelites from the Sierra Norte of Oaxaca and reported the following variations: 65.96 to 500.99, 255.7 to 2418.6, 348.4 to 1021.8, 1467.2 to 4097.3, and 4.4 to 88.5 mg 100 g⁻¹ in P, Ca, Mg, K, and Na contents, respectively. Gálvez and Peña [47], in 22 species of leaf quelites, reported variations from 332.6 to 3717.3, 1165.9 to 6733.5, and 157.6 to 600.3 mg 100 g⁻¹ in Ca, K, and Mg, respectively. These different patterns of variation recorded in the current study for the flowers of D. americana and those for species of leaf quelites (edible leaves) suggest that both sources contribute P, Ca, K, and Mg to the diet, and the differences in the concentrations of each macroelement are due, in part, to the environmental effects of plant growth, species or genotypes and interactions of species/genotypes and the environment.

Manzanero-Medina et al. [23] obtained samples of D. americana from the local markets of Zimatlán de Álvarez and Villa de Zaachila in the Valles Centrales of Oaxaca, Mexico. They reported average Ca and Mg contents of 344.88 and 47.23 mg 100 g⁻¹, respectively, which are higher values of Ca than those reported in the present work (243.6 mg 100 g⁻¹) but lower values of Mg (259.4 mg 100 g⁻¹). In both cases, different detection protocols and equipment were used; in the first case, an atomic absorption spectrophotometer was used, and in the second case, inductively coupled plasma–optical emission spectrometry (ICP-OES) was used, revealing differences in the sensitivity of the equipment, in addition to the inherent variations in samples, making objective comparisons difficult. However, both studies revealed some of the variability in the composition of macroelements in the inflorescences of D. americana in Oaxaca.

For the inflorescences of D. americana, the micromineral concentrations were Si > Fe > Mn > Cu > Mo, with significant differences in terms of geographical origin. In the case of the evaluations carried out by Pascual-Mendoza et al. [31] in eight species of leaf quelites, the macroelement pattern was Fe > Cu > Mn > Zn, with average variations of 7.86 to 40.99, 1.67 to 38.70, 4.11 to 37.09, and 2.32 to 10.6 mg 100 g⁻¹ in fresh weight, and the results in this work ranged from 3.96 to 6.31, 0.57 to 1.59, 1.31 to 2.50 and 3.77 to 5.45 mg 100 g⁻¹ in dry weight, respectively. For D. americana, Manzanero-Medina et al. [23] estimated values of 10.98, 0.99, and 4.25 mg 100 g⁻¹ for the Fe, Cu, and Zn contents, respectively. While it is important to understand the differences in concentrations due to the differential effects between the species and detection equipment, both studies reported the nutritional and health potential of the microelements of D. americana, including other native species of quelites distributed in Oaxaca. Furthermore, the P, Ca, Mg, Na, Cu, Mn, and Zn contents in D. americana flowers shown in this work could contribute to the recommended daily intake requirements for adults [43].

The consumption of immature inflorescences of pacaya or tepejilote (C. tepejilote) and other palms is prevalent in the tropical and subtropical regions of southern-southeast Mexico, and these plants are even cultivated in these regions. Bean dishes with tepejilote are very popular, simply boiled or combined with eggs, among many forms of local preparation. From region to region, it is harvested or cultivated at different times of the year, but it is common in traditional markets. The samples described here in terms of macro- and microelements were collected in the municipalities of Santa Maria Jacatepec, Santiago Jocotepec, San Juan Bautista Valle Nacional, San Felipe Jalapa de Diaz, and Ayotzintepec from the lower Chinanteca zone in the region of Papaloapan, Oaxaca, Mexico, with a majority of the population constituting the Chinanteco indigenous group.

The macroelement contents in C. tepejilote were ordered from highest to lowest as follows: K > Ca > S > P > Mg > Na, and significant differences were found for all the minerals except Na between and within locations. For inflorescences of C. tepejilote collected in Tabasco, Centurión-Hidalgo et al. [22] obtained concentrations of 229.13, 2479, 103.26 and 6.77 mg 100 g⁻¹ of K, Ca, Mg, and Na, respectively, via atomic absorption spectrometry (AAS), and our results presented variations from 2802.6 to 3650.3, 2263.1 to 3383.7, 533.1 to 1281.0, and 9.95 to 43.67 mg 100 g⁻¹, respectively, but were estimated via optical emission spectrometry (ICP-OES). On the other hand, Santiago-Saenz et al. [3] reported variations in the leaves of Amaranthus hybridus L. (amaranth), Chenopodium berlandieri L. (huauzontle), and Portulaca oleracea L. (purslane) from 4610 to 6920, 900 to 1980, and 300 to 780 mg 100 g⁻¹ for K, Ca, and Mg, respectively, via AAS. These similarities and differences with respect to the results of other authors for C. tepejilote or other species of leaf quelites show that C. tepejilote can contribute relevant amounts of K, Ca, Mg, and Na to the human diet. One of the restrictions for the consumption of C. tepejilote and similar species is that they grow only in tropical and subtropical areas of the country, and their consumption is unknown beyond those regions.

For inflorescences of C. tepejilote collected in Tabasco, Centurión-Hidalgo et al. [22] reported concentrations of 25.01, 4.94, and 0.23 mg 100 g⁻¹ of Fe, Zn, and Cu, respectively. In this work, variations were obtained from 8.12 to 13.67, 7.27 to 9.23, and 1.10 to 3.09 mg 100 g⁻¹ for Fe, Zn, and Cu, respectively. On the other hand, in 30 samples of Amaranthus tricolor L., Shukla et al. [48] reported variations from 78.3 to 230.6 mg 100 g⁻¹ for Fe and 59.2 to 123.0 mg 100 g⁻¹ for Zn. Apart from the differences in detection equipment used during the evaluations, it is possible to establish that the inflorescence of C. tepejilote is a source of Fe and Zn, two of the main elements associated with anemia, where 8 to 18 mg per day of Fe and Zn are needed for an adult diet [43]. The high contribution of Si to the composition of C. tepejilote should be highlighted. Depending on the origin of the sample, the concentrations can vary from 102.7 to 201.0 mg 100 g⁻¹, where 30 mg per day is required for an adult.

The PCA (Figure 1) revealed differences between species in terms of the mineral composition of the evaluated inflorescences, which can be addressed in other studies such as those on the influence of specific environmental factors, such as temperature, soil characteristics, and associated vegetation. Therefore, considering the nutrient requirements guide of the Institute of Medicine of the National Academies [43] and the results of mineral concentrations in Y. filifera, A. salmiana, C. tepejilote, and D. americana inflorescence, these findings suggest that these inflorescences can complement the dietary mineral requirements of people in the regions where they are distributed and also in other regions where they are well known. These inflorescences can support the recommended daily diets of families, particularly in vulnerable social groups where it is difficult to satisfy daily mineral needs. In addition, further studies of mineral composition are needed; for example, specific aspects of preparation may be needed to maintain the major mineral concentrations in food.

5. Conclusions

The evaluation of macro- and microelements in inflorescences of Y. filifera (izote), A. salmiana (maguey pulquero), D. americana (cuachepil or guachepil), and C. tepejilote (tepejilote or pacaya) was performed using samples with different geographical origins in Oaxaca, Mexico, and revealed that the locality or community where the plants and inflorescences grew and developed significantly influenced the concentration of minerals, except for the Na content in izote, maguey pulquero, cuachepil, and tepejilote; the Cu content in izote and tepejilote; and the Si content in maguey pulquero. Significant differences were also observed in mineral content for samples from the same community or intralocalities, mainly in izote, cuachepil, and tepejilote. These two patterns reveal that the mineral contents of these species vary between and within geographic locations according to their distribution since not all evaluated species are distributed in all the regions.

The main order of macroelement concentrations from highest to lowest in the inflorescences of the evaluated species was K > Ca ≥ P > Mg > S > Na. Among the species, the patterns with low values corresponded to cuachepil, maguey pulquero, and izote, and the high values corresponded to tepejilote. For microelements, the general pattern of concentrations across the evaluated species was Si > Fe ≥ Zn > Mn > Cu > Mo. In this case, the high values correspond to tepejilote, and the low values correspond to maguey, cuachepil, and izote. Silicon was a highly accumulated microelement in all the evaluated inflorescences and has potential as a food source to counteract metabolic disorders associated with low ingestion. Considering the macro- and microelement contents of the evaluated species, C. tepejilote stood out for its relatively high content. Due to its contribution to diet and health and despite the effect of the plant growth environment on the development and chemical composition of inflorescences, the evaluated species are a food option for sources of macro- and microelements in each dispersal region of the species evaluated in Oaxaca, Mexico, and other countries.

Changes in dietary patterns due to the consumption of processed and refined foods have had unfavorable repercussions on human nutrition and health. The revalorization of natural products with nutritional potential, such as edible flowers traditionally consumed in rural communities by ethnic groups, remains a relevant topic of study. However, the differences in chemical composition between plant populations and species due to environmental influences, growth conditions, genotypic interactions, and their implications for human health must be considered in depth in the future.