Atividade antioxidante e microencapsulação de extrato etanólico de tomilho (Thymus vulgaris L.)

Abstract

The current trend in search for better quality of life, coupled with concern about health and diet, has driven research in the search for natural products with positive biological characteristics, is to be used as food supplement or substitute the synthetic compounds in foods. Thus, it becomes necessary to use natural products in the formulation of ingredients with high added value, as in cases of microencapsulated natural products. Thyme (Thymus vulgaris L.) is an aromatic herb belonging to the family Lamiaceae, and is widely used as a spice in cooking typical. Within this context, this study aimed to evaluate the content of total phenolic compounds, total flavonoids and antioxidant potential of hydroalcoholic extract of thyme (Thymus vulgaris L.), as well as produce microparticles by spray – drying process, using mixture of maltodextrin and modified starch as wall material. The extract of thyme submitted content 33,55 mg EAG.g-1 for phenolic compounds and 23,46 mg EQ.g-1 for total flavonoids . Antioxidant activity were found values of 132,29 mmol trolox. g-1 for the method to sequester DPPH , 265,79 μmol of TEAC.g-1 for the method of abduction of radical ABTS , 314,72 μmol Fe+2.g-1 for the method of reducing power iron - FRAP, and showed 89.62 % antioxidant capacity in inhibiting the oxidation of linoleic method for β-caroteno/ácido system. The thyme extract showed appreciable content of total phenolic compounds , total flavonoids and antioxidant activity. Microencapsulation of thyme by spray-drying yielded smooth, homogeneous microspheres as the form and structure without fissures or cracks, and showed an efficiency of 68 % compared to phenolic compounds, making thyme a potential ingredient for industrial application, a product natural with added value.