Chemical Composition and Antimicrobial Activity of Laurus nobilis L. Essential Oils from Bulgaria

Abstract

Laurel, Laurus nobilis L. is an evergreen plant belonging to the Lauraceae family, native to Southern Europe and the Mediterranean area. This is the first report on the composition and bioactivity of laurel essential oil (EO) from Bulgaria. The oil yield was 0.78%, 0.80%, and 3.25% in the fruits, twigs, and leaves, respectively. The main constituents in the fruit EO were 1,8-cineole (33.3%), α-terpinyl acetate (10.3%), α-pinene (11.0%), β-elemene (7.5%), sabinene (6.3%), β-phellandrene (5.2%), bornyl acetate (4.4%), and camphene (4.3%); those in the twig EO were 1,8-cineole (48.5%), α-terpinyl acetate (13.1%), methyl eugenol (6.6%), β-linalool (3.8%), β-pinene (3.4%), sabinene (3.3%) and terpinene-4-ol (3.3%); and the ones in the leaf EO were 1,8-cineole (41.0%), α-terpinyl acetate (14.4%), sabinene (8.8%), methyl eugenole (6.0%), β-linalool (4.9%), and α-terpineol (3.1%). The antibacterial and antifungal properties of laurel EOs were examined according to the agar well diffusion method. The leaf EO showed antibacterial and antifungal activities against almost all strains of the microorganisms tested, whereas the twig EO was only able to inhibit Staphylococcus aureus. Pseudomonas aeruginosa АТСС 9027 and Escherichia coli ATCC 8739 were the bacterial strains that showed the highest resistance to the laurel EO. The results can benefit the EO industry and biopesticide development.

A Comparative Study of the in Vitro Antimicrobial and Synergistic Effect of Essential Oils from Laurus nobilis L. and Prunus armeniaca L. from Morocco with Antimicrobial Drugs: New Approach for Health Promoting Products

“…Apricot EO acts against E. coli and Klebsiella pneumoniae with an MFC of 23.4 mg/mL and C. parapsilosis with 11.70 mg/mL. Our findings are in agreement with those reported by several authors for the same species [16,29]. Table 2.…”

“…The obtained data showed that the composition of the studied laurel EO differed quantitatively to those previously reported in samples from other geographical regions such as Italy, Turkey, Cyprus, Tunisia and Bulgaria. In fact, the concentration of eucalyptol in our samples was lower than the values recorded in Tunisia (56%) [26], Cyprus (58.59%) [27] and Bulgaria (41%) [16]. However, it was higher compared with those found in other studies, namely Algeria (34.62%) [15].…”

“…Dried laurel leaves are used extensively in cooking, in hair lotions because of their antidandruff activity and for the external treatment of psoriasis [14]. The EO from laurel leaves exhibits several biological properties such as antiviral, antimicrobial and insecticidal activity [13,15,16]. Moreover, it can be used in food preservation [17], cancer treatment [18] and aromatherapy [19].…”

Volatile Antimicrobial Agents and In Vitro Methods for Evaluating Their Activity in the Vapour Phase: A Review

“…On the other hand, volatile substances such as EOs derived from plant species with a GRAS (generally recognized as safe) status based on their long history of use have great potential as natural preservatives in the food industry and agriculture, since the U. S. Food and Drug Administration (FDA) approved their safety for food application. Various studies evaluating the antimicrobial activity of some GRAS EO-bearing plant species or their constituents have been previously published [77][78][79], but only a few have directly focused on their vapour phase.…”

Absolute quantification of terpenes in conifer-derived essential oils and their antibacterial activity

“…However, there is no particular data suggesting synergism between bornyl acetate and other terpenes. Some studies have demonstrated synergism mainly produced between oxygenated terpenes (Sokovic et al 2010;Fidan et al 2019;Bassole and Juliani 2012;Novato et al 2019;Gavaric et al 2015;Jagannath et al 2012). Thus, in further studies, synergism of bornyl acetate with other terpenes should be investigated.…”