Next Article in Journal
A Peptide Nucleic Acid (PNA) Masking the miR-145-5p Binding Site of the 3′UTR of the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) mRNA Enhances CFTR Expression in Calu-3 Cells
Next Article in Special Issue
Essential Oil Phytocomplex Activity, a Review with a Focus on Multivariate Analysis for a Network Pharmacology-Informed Phytogenomic Approach
Previous Article in Journal
Recent Advances in Synthesis of Benzothiazole Compounds Related to Green Chemistry
Previous Article in Special Issue
Essential Oil-Based Design and Development of Novel Anti-Candida Azoles Formulation
Open AccessArticle

Toxic, Radical Scavenging, and Antifungal Activity of Rhododendron tomentosum H. Essential Oils

1
State Research Institute Center for Physical Sciences and Technology, Department of Organic Chemistry; Sauletekio Ave. 3, LT–10222 Vilnius, Lithuania
2
Nature Research Centre, Laboratory of Biodeterioration Research; Akademijos 2, LT–08412 Vilnius, Lithuania
*
Author to whom correspondence should be addressed.
Academic Editors: Valtcho Jeliazkov, Murray B Isman, Farid Chemat, Vassya Bankova and Niko Radulović
Molecules 2020, 25(7), 1676; https://doi.org/10.3390/molecules25071676
Received: 29 January 2020 / Revised: 1 April 2020 / Accepted: 2 April 2020 / Published: 5 April 2020
The chemical composition of eight (seven shoot and one inflorescence) essential oils (EOs) of Rh. tomentosum H. plants growing in Eastern Lithuania is reported. The plant material was collected during different phases of vegetation (from April to October). The oils were obtained by hydrodistillation from air-dried aerial parts (leaves and inflorescences). In total, up to 70 compounds were identified by GC−MS and GC (flame-ionization detector, FID); they comprised 91.0 ± 4.7%–96.2 ± 3.1% of the oil content. Sesquiterpene hydrocarbons (54.1 ± 1.5%–76.1 ± 4.5%) were found to be the main fraction. The major compounds were palustrol (24.6 ± 2.6%–33.5 ± 4.4%) and ledol (18.0 ± 2.9%–29.0 ± 5.0%). Ascaridol isomers (7.0 ± 2.4%–14.0 ± 2.4% in three oils), myrcene (7.2 ± 0.3% and 10.1 ± 1.3%), lepalol (3.3 ± 0.3% and 7.9 ± 3.0%), and cyclocolorenone isomers (4.1 ± 2.5%) were determined as the third main constituents. The toxic activity of marsh rosemary inflorescence and shoot oils samples was evaluated using a brine shrimp (Artemia sp.) bioassay. LC50 average values (11.23–20.50 µg/mL) obtained after 24 h of exposure revealed that the oils were notably toxic. The oil obtained from shoots gathered in September during the seed-ripening stage and containing appreciable amounts of palustrol (26.0 ± 2.5%), ledol (21.5 ± 4.0%), and ascaridol (7.0 ± 2.4%) showed the highest toxic activity. Radical scavenging activity of Rh. tomentosum EOs depended on the plant vegetation stage. The highest activities were obtained for EOs isolated from young shoots collected in June (48.19 ± 0.1 and 19.89 ± 0.3 mmol/L TROLOX (6-hydroxy-2,5,7,8-tetra-methylchromane-2-carboxylic acid) equivalent obtained by, respectively, ABTS+ (2,2′-amino-bis(ethylbenzothiazoline-6-sulfonic acid) diammonium salt) and DPPH(2,2-diphenyl-1-picrylhydrazyl) assays). Agar disc diffusion assay against pathogenic yeast Candida parapsilosis revealed the potential antifungal activity of EOs. An alternative investigation of antifungal activity employed mediated amperometry at yeast Saccharomyces cerevisiae-modified electrodes. The subjection of yeast cells to vapors of EO resulted in a three to four-fold increase of electrode responses due to the disruption of yeast cell membranes. View Full-Text
Keywords: Rhododendron tomentosum H.; Ericaceae; essential oil composition; antifungal activity; antioxidant tests; toxicity in vivo; amperometry Rhododendron tomentosum H.; Ericaceae; essential oil composition; antifungal activity; antioxidant tests; toxicity in vivo; amperometry
Show Figures

Graphical abstract

MDPI and ACS Style

Judzentiene, A.; Budiene, J.; Svediene, J.; Garjonyte, R. Toxic, Radical Scavenging, and Antifungal Activity of Rhododendron tomentosum H. Essential Oils. Molecules 2020, 25, 1676.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Search more from Scilit
 
Search
Back to TopTop