Variação sazonal no estudo metabolômico e na atividade antioxidante da erva-cidreira (melissa officinalis).

Abstract

The use of plants as a form of food with beneficial purposes to human health has aroused the interest in knowing the properties and performance of plants under their effects in the body. The Lamiaeceae family is known to present active principles with important effects, Melissa officinalis, for example, is a plant that acts in the treatment of diseases, relief of symptoms and by having antioxidant substances.The present work aimed to evaluate Melissa officinalis, consumed mainly in the form of tea and to contribute with more information about the plant. For this work, aerial parts of Melissa officinalis were collected at two hours, at 7:00 am and 4:00 p.m. for their metabolomic study, through gas chromatography and mass spectrophotometer (GC-MS), determination of antioxidant activity by DPPH method, using ascorbic acid as the standard compound, and the antioxidant capacity equivalent to trolox. For the determination of the total phenolic compounds, by means of Folin Ciocalteau reagent and gallic acid as standard. The result of the metabolomic study found in the greater amount of the citral compound in the afternoon and concentrations of the similar constituents in relation to the two samples. For the determination of the antioxidant activity, the DPPH test, there was a significant difference of the EC50 (effective concentration) between the morning collections (146.46 ± 1.35 μg / mL) and the afternoon (255.5 ± 0.9 μg / ML), as compared to ascorbic acid (7.37 ± 0.05 μg / mL) and for antioxidant capacity equivalent to trolox, the morning sample had an EC50 value of 48.48 ± 2.48 μg / mL , With a significant difference in relation to the afternoon collection, with an EC50 of 55.46 ± 1.04 μg / mL. There were also differences between the samples and Trolox, a standard compound, which presented an EC50 of 2.03 ± 0.03 μg / mL, both methods, reported higher activity in the morning. For the determination of the total phenolic compounds, the morning period presented 2.01 ± 0.08 mg / g and the afternoon time with 1.16 ± 0.08 mg / g, presenting a significant difference between them. This work concluded that the correct time for harvesting the herbs is essential to obtain the desired constituents, and suggests more research aimed at the determination of antioxidant activity and determination of the total phenolic compounds in relation to the time of harvest.