Effect of two dehydration processes on extracts from Opuntia atropes and characterization of polyphenolic compounds by ultra high-resolution liquid chromatograph coupled with mass spectrometry

ABSTRACT

The objective of this research was to evaluate the polyphenolic compounds, the antioxidant activity, and the individual identification of the different types of phenolic compounds in dried extracts of Opuntia atropes. O. atropes extract was dehydrated in a drying oven at 50°C/24 h and by nano-spray drying at 105°C. Drying by nano-spray did not affect the content of phenolic compounds or the antioxidant activity of the O. atropes extract, presenting values of 11.80 ± 0.61 mg of gallic acid equivalent/g of phenolic acids, 22.26 ± 1.02 mg quercetin equivalent/g of flavonoids and inhibition percentage of the radical DPPH^• (2,2-. diphenil-1-picrilhidrazil) and ABTS^•+ (2,2ʹAzinobis(3-ethylbenzothiazoline-6 sulfonic acid)) of 17.92 ± 0.31 and 54.08 ± 0.48, respectively. In the powdered extracts of O. atropes, glycosides of kaempferol and isorhamnetin were mainly identified by ultra high-performance liquid chromatography coupled to mass spectrometry. Mediorresinol lignan was identified for the first time in this Opuntia species.

RESUMEN

El objetivo de esta investigación fue evaluar los compuestos polifenólicos, la actividad antioxidante y la identificación individual de los diferentes tipos de compuestos fenólicos en extractos secos de Opuntia atropes. El extracto de O. atropes se deshidrató en un horno de secado a 50°C/24 h y mediante secado por nano-pulverización a 105°C. El secado por nano-pulverización no afectó el contenido de compuestos fenólicos ni la actividad antioxidante del extracto de O. atropes, presentando valores de 11.80 ± 0.61 mg EAG (equivalentes de ácido gálico)/g de ácidos fenólicos, 22.26 ± 1.02 mg EQ (equivalentes de quercetina)/g de flavonoides y porcentaje de inhibición del radical DPPH^• (2,2-difenil-1-picrilhidrazilo) y ABTS^{• +} (ácido 2, 2ʹ Azinobis-3-etil- benzotiazolin-6 sulfónico) de 17.92 ± 0.31 y 54.08 ± 0.48, respectivamente. En los extractos en polvo de O. atropes, se identificaron principalmente los glucósidos de kaempferol e isoramnetina mediante cromatografía líquida de ultra alta resolución acoplada a espectrometría de masas. El lignano de mediorresinol se identificó por primera vez en esta especie de Opuntia.

KEYWORDS:

• Opuntia atropes
• dehydration
• nano-spray
• polyphenolic profile
• UPLC-Q/TOF-MS²
• antioxidant activity

PALABRAS CLAVE:

• Opuntia atropes
• deshidratación
• nano-pulverización
• perfil polifenólico
• UPLC-Q/TOF-MS²
• actividad antioxidante

Acknowledgments

Eunice Tranquilino Rodriguez gratefully acknowledges the support of CONACyT for the PhD scholarship received, Scholar number 286273.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability

The data used to support the findings of this study are available from the corresponding author upon request.