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In the present study, the leaves of Manilkara zapota (L.) P. Royen (Sapotaceae), an evergreen tree recognized for its medicinal properties in Southern Mexico, were used as a model to study the effect of different drying temperatures on its metabolic profile and therefore, its antioxidant potential. For this purpose, a methanol extraction of leaves dried at room temperature (25 °C) or by heat convection (50, 75 and 100 °C) were compared in terms of drying efficiency, yield of extraction, total phenol content, 1H-NMR metabolic profile, and DPPH antioxidant activity. The drying curves enabled the fact to be uncovered that drying efficiency improves with increase of temperature, as does the level of total phenols and antioxidant activity. A metabolomics approach using principal component analysis (PCA) and orthogonal projections to latent structures discriminant analysis (OPLS-DA) of the corresponding 1H-NMR profiles allowed the impact of the drying temperature on their metabolic profile to be documented and also, caffeic acid and epicatechin as main secondary metabolites contributing to the antioxidant activity of M. zapota to be identified.

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Byrsonima crassifolia leaves were extracted via maceration (BrMa), percolation (BrPer), soxhlet (BrSox) and sonication (BrSon). Spectrophotometric estimation of chlorophylls and analysis of cumulative extraction allowed the characterization of the extraction process. Under these experimental conditions, the extraction efficiency for each method was greater than 99%. The best yield was recorded by Soxhlet (7.29±0.21%), the best extraction rate was by sonication (m: 0.032±0.004; r 2 : 0.96±0.02) and maceration showed less variations in estimation of chlorophyll a and b. On the other hand, pharmacological evaluation in a rat ileum strips allowed identify that BrMa, BrPer, BrSox and BrSon reduce the spontaneous contractions (E max : 38.54±2.03, 28.9±1.6, 31.87±1.79, and 29.09±1.27%; EC 50 : 11.6±2.38; 13.22±2.83; 39.74±2.64 and >50 µg/mL, respectively) of ileum strips in a concentration-dependent manner, however, the effects were significantly lower than papaverine (E max : 59.32±2.57%; EC 50 : 7.11±1.0 µg/mL). These results indicated that according to extraction method there are variations in the metabolic content as well as in the pharmacological actions induced by B. crassifolia extracts. Finally, there are a low correlation between extraction temperature (r > 0.87) and spasmolytic activity.

Rhizophora mangle, Avicennia germinans y Laguncularia racemosa son especies presentes en la Reserva de la Biosfera Los Petenes, Campeche, México, y cuentan con reportes de usos tradicionales en la salud humana. El presente trabajo plantea identificar la especie idónea para la búsqueda de entidades químicas con aplicaciones terapéuticas. Las hojas de L. racemosa tienen el mejor rendimiento de extracción metanólica (35.29±0.45%); mediante espectroscopía y métodos químicos se identifica una gran diversidad de familias de metabolitos secundarios en todas las especies. El mayor contenido de clorofilas (0.27±0.03 mg/g), carotenoides (0.015±0.002 mg/g) y fenoles simples (0.79±0.001 mg/g eq. AG) se registra en R. mangle y flavonoides (0.228±0.001 mg/g eq. Q) en A. germinans. L. racemosa presenta la mejor actividad antioxidante en el modelo de DPPH (CE50: 59.2 µg/mL; Emax: 68.8±1.6%), sin embargo, es menor a C. sinensis (CE50: 4.85 µg/mL; Emax: 93.37±0.14%). Finalmente, mediante FTIR se identifica la presencia de AG, Q y catequina (C) en R. mangle y se estima un 0.33 y 0.73% de AG en R. mangle y A. germinans, respectivamente. L. racemosa es la especie idónea para el desarrollo de un estudio fitoquímico biodirigido orientado a la identificación de entidades químicas no polifenólicas con actividad antioxidante.