Improving the bioactivity of medicinal plants using gamma radiation: Thymus vulgaris L. infusions as a case-study
Conference Paper
Overview
Overview
abstract
Foundation for Science and Technology (FCT, Portugal) for financiai support to CIMO (PEst-OE/AGR/UI0690/2013), CTN (RECI/AAG-TEC/0400/2012), REQUIMTE (UID/QUI/50006/2013 - POCI/01/0145/
FERDER/007265) and L. Barms grant (BPD/107855/2015). The auíhors are also grateful to "MaisEn/as -
Aromáticas e Medicinais" company for pmvidiry lhe samples.
The bioactive compounds present in medicinal plants have shown beneficiai effects in the prevention
of various diseases due to their capacity to act positively in several biological mechanisms [1] with
reduced adverse effects [2].
The aim of this work was to evaluate the effects of gamma radiation processing, at doses of 1 and 10
kGy, on antioxidant activity and phenolic composition of a medicinal plant used m traditional medicine
- fhymus vulgaris L., and the results compared with the contrai sample (O kGy). After plants
processing, an infusion was prepared, from irradiated and non-irradiated samples to evaluate
antioxidant properties through: free radicais scavenging activity, reducing power and inhibition of lipid
peroxidation in brain cell homogenates (TBARS assay) methods. And phenolic compounds were
analysed by HPLC-DAD-ESI/MS.
Com"paring'the results obtained for contrai (O kGy) and irradiated samples (at 1 and 10 kGy), it was
evident that gamma irradiation at the dose of 10 kGy improved free radical scavenging actiyity,
reducing power and lipid peroxidation inhibition capacity of the infusions (lower values of EÇso).
RegardFng phenolics, thirteen compounds were detected in the infusions prepared either from
irradiated or non-irradiated samples. However, the global phenolic profile was not changed. In this
way, gamma radiation could be considered as a suitable treatment to be used in dried plants in
particular, to improve bioactive properties of Thymus vulgaris L. related to its phenolic composition [3].
