Pelecyphora macromeris. Chemical profiles of roots and stems

Material maintained in culture and a greenhouse

Pelecyphora macromeris (Engelm.) D.Aquino & Dan.Sánchez is the accepted name of a species formerly treated as Coryphantha macromeris (Engelm.) Britton & Rose. The combination in Pelecyphora was published in 2022. Its natural range covers southern New Mexico, western Texas and northeastern Mexico. The 2019 study by Cabañas-García and coauthors uses the name Coryphantha macromeris. Material was identified at species level. [2-WWW][Cabañas-García et al. 2019, POWO, 11 October 2026; Cabañas-García et al., pp. 1, 13]

The plants came from the in vitro culture bank of the Autonomous University of Aguascalientes. They were maintained for a year on MS with 3% sucrose and 8 g/l agar at 25°C, under a sixteen-hour day and about 40 µmol photons/m²/s. After acclimatization, they spent another year in a greenhouse. Identification was documented by specimen HUAA 6386. Plants prepared in this way supplied both extracts, compared by plant part. [Cabañas-García et al. 2019, p. 13, Plant Material]

Preparation of two extracts

Roots were separated from above-ground parts. Material was ground and dried for a week at 40°C in darkness. Powdered samples were extracted three times with methanol in a thirty-minute ultrasonic bath. After solvent evaporation, extract solutions of 2,5 mg/ml were prepared for analysis. This procedure determines which compounds could enter the fraction studied. [Cabañas-García et al. 2019, p. 13, Sample Preparation]

Ultra-high-performance liquid chromatography with UV spectrum detection and high-resolution tandem mass spectrometry was used. Chromatography separates mixture components over time, while measurement of ion mass and fragmentation provides information about their possible structures. Analysis was conducted in negative-ion mode with mass accuracy better than 5 ppm. Retention time, UV spectrum, ion mass and breakdown products were assessed. [Cabañas-García et al. 2019, pp. 13–14, LC Parameters and MS Parameters]

Sixty assignments and nine unknown signals

A total of 69 signals were separated in the two extracts. Sixty received preliminary identifications and nine remained unknown. In the results table, the authors describe the identifications as tentative. Proposed structures rely on ion characteristics and comparison with literature data. Assignments concern components of the extract mixture analysed by this method. [Cabañas-García et al. 2019, pp. 2–10, Table 1]

Twenty-six signals were detected only in above-ground parts, nineteen only in roots and twenty-four in both extracts. The numbers describe signal presence in qualitative analysis of the two fractions. The overlapping part of the profile indicates compounds proposed in both plant parts within the sensitivity of the procedure used. [Cabañas-García et al. 2019, pp. 2–12, Table 1]

Frequently identified groups included ferulic acid, its isomers and derivatives, and the acid termed piscidic acid in the publication and its derivatives. Ferulic acid and fertaric acid were proposed in both fractions. Some assignments of derivatives of this acid occurred only in above-ground material, others in roots or both parts. The comparison concerned the chromatographic profile and ion fragmentation, retaining the degree of identification confidence from the table. [Cabañas-García et al. 2019, pp. 4–8, Table 1]

The authors drew attention to relatively large signals of some phenolic acids. Signal height depends on extraction and the compound's response during ionization. The authors assessed relative peak sizes in the chromatographic profile. The analysis was qualitative, and the stated concentration of 2,5 mg/ml referred to the entire extract in the analytical sample. [Cabañas-García et al. 2019, pp. 11–14, Discussion and methods]

Scope of the analysis of greenhouse material

The discussion refers to biological activity of some proposed compounds known from other publications. The experimental part of this study covered chemical analysis of extracts. Results determine the proposed presence and distribution of substances in greenhouse material. [Cabañas-García et al. 2019, pp. 11–14]

The profile was obtained after the described history of growth in culture and a greenhouse. The comparison covered roots and above-ground parts of this material. The number of independent plants forming each sample remained unspecified in the report, so extract fractions are the units of the comparison presented. [Cabañas-García et al. 2019, pp. 13–14, Materials and methods]

Comparison of roots and above-ground parts forms the basis for a chemical description of the maintained material. It identifies signals shared and specific to individual fractions, and groups whose structures require resolution. The authors' proposed possibility of biotechnological use concerns further understanding and obtaining of compounds. The report presented remains a study of extract profiles. [Cabañas-García et al. 2019, pp. 11–14, Discussion and conclusions]