Dosage of flavanols in fresh and dried leaves of passion fruit

Abstract

The passion fruit (Passiflora sp.), medicinal plant widely used in the food and pharmaceutical industries. The content of flavanols in fresh leaf may vary depending on the age or position of the sampled leaf of the plant and the interaction with the environment. This study aimed to determine the levels of flavanols in fresh leaves and dried by artificial drying (conventional oven) and natural processes (thin layer) of ethanol extracts of Passiflora edulis Sims. Leaves the middle third, collected from one access, were sent to the laboratory of medicinal plants, which were organized and whispered in treatments. Voucher specimen is deposited in the Herbarium of EPAMIG under number PAMG57074. Whole leaves were placed in multifoliate paper and subjected to the drying process using a conventional oven at 40 °C and in thin layer at room temperature (25 °C). The percentages of dry mass and water loss in drying processes were calculated. Ethanol extracts were made from fresh leaves (TRFF), dried leaves in conventional oven (TREC) and thin layer (TRCD) by maceration. After extraction, the extracts were evaporated and the dry residue yield calculated. The determination of flavanols was assayed by the vanillin method (colorimetry), adapted of Jayaprakasha et al. [1], using catechin as a standard. The analyzes were performed with four replicates and data were submitted to analysis of variance and average test at 1% significance. The highest water loss was TRCD = 81.94% and TREC = 79.81%, which shows that, in this experiment, the process of drying thin layer, of leaves of passion fruit, was effective. The best yields of the extracts were in TRCD and TREC. The highest amount of flavanols was fresh leaves. The method of artificial drying in conventional oven at TRCD, the flavanols were reduced by 62% (Table 1), indicating that this process was less effective than natural drying, in preservation of biomarkers, pharmacologically active compounds, in the leaves of passion fruit.