Fluctuations of phenols and flavonoids in infusion of lemon verbena (Lippia citriodora) dried leaves during growth stages

Abstract

Purpose

The purpose of this paper is to determine the total phenol content (TP) and total flavonoid content (TF) fluctuations in different infusions of lemon verbena. Dried leaves were harvested in May, July and October and prepared at various soaking times (5-20 min).

Design/methodology/approach

The Folin-Ciocalteu method was used to determine TP, while TF was determined by the aluminum chloride method.

Findings

According to the results, the July harvest had the highest content of TP and TF, followed by May and October. Temperature and soaking time play a role in the proportion of released phenols and flavonoids (p < 0.05), whereas the content in continuous infusion is higher than infusion (without boiling) .TP and TF in infusion increase until 20 min, while concentration is convergent in continuous infusion after10 minutes, where no significant difference is seen. In the flowering stage, TP is close in comparison with the vegetative stage.

Originality/value

Harvest time plays a role in the content, so it is best to prepare infusion from lemon verbena before the flowering period, when people drink it, as the results show. According to the authors’ knowledge, this is the first work that studied the variation in phenol and flavonoid content during different stages of growth with soaking time in drenched lemon verbena leaves.

Citation

Naser Aldeen, M.G., Mansoor, R. and AlJoubbeh, M. (2015), "Fluctuations of phenols and flavonoids in infusion of lemon verbena (Lippia citriodora) dried leaves during growth stages", Nutrition & Food Science, Vol. 45 No. 5, pp. 766-773. https://doi.org/10.1108/NFS-04-2015-0037