The composition and antibacterial activity of essential oils in three Ocimum species growing in Romania

Abstract

In this study the glandular hair morphology, chemical composition and antimicrobial activity of the essential oils from three Ocimum species have been investigated (Ocimum basilicum L. var. Genovese, O. gratissimum and O. tenuiflorum). The indumentum shows little variation among the investigated species with both glandular and non-glandular hairs presents. Glandular hairs on the three species are peltate and capitate (with various cell numbers in the stalk and gland). The samples of essential oils obtained from the plant aerial organs by hydrodistillation have been analyzed by GC-MS. Linalool (65.38%, 74.22%, 38.60%), eugenol (5.26%, 3.47%, 10.20%) and tau-cadinol (8.18%, 3.47%, 10.20%) appear as the main components in Ocimum basilicum L. var. Genovese, O. gratissimum and O. tenuiflorum. The oils also contain lower levels of α-bergamotene, 1,8-cineole, germacrene D, β-ocimene, α-caryophyllene, camphor, and α-guaiene. All essential oils showed antibacterial activity against Staphylococcus aureus and Escherichia coli depending on their concentration. Ocimum basilicum L. var. Genovese oil produced the strongest antibacterial effect on S. aureus and E. coli.

Chemical Composition and Antimicrobial Activity of Essential Oils ofOcimum basilicum,Ocimum canumandOcimum gratissimumin Function of Harvesting Time

“…On the other hand, Kpoviessi et al, 31 found that p-cymene was predominant in O. gratissimum, followed by thymol and γ-terpinene. The investigated chemotype differs from those reported previously, which were the eugenol type 12,27,34 , linalool type 39 , methyl cinnamate type 40 and ethyl cinnamate type 41 . Variations of the percentages of chemical constituents were observed according to daytime of collection, including major constituent as thymol (28.3-37.7 %), γ-terpinene (12.5-19.3 %) and p-cymene (12.1-18 %).…”

“…This could be related to lower thymol content (28.3 %). The activity of O. gratissimum oil against some bacteria and fungi were also reported in previous works 11,31,39,46 . Among previously published studies, the antibacterial activity of thymol-containing oil of O. gratissimum was only reported in the work of Ngassoum and co-authors 37 against some Gramnegative and Gram-positive bacteria other than L. monocytogenes and S. Typhimurium.…”

Antifungal activity, yield, and composition of Ocimum gratissimum essential oil

“…The major chemical compounds found in their study were thymol (26%), followed by g-terpinene (20%) and p-cymene (17.6%). Stefan et al (2013) analyzed the chemical composition of EO from three plants of the Ocimum genus cultivated in Romania. Linalool was also the major compound found in the EO of O. gratissimum.…”

GC—MS analysis of the essential oil of Ocimum gratissimum L. growing desolately in South India

“…Diverse pharmacological activities, viz., anthelmintic [5], antiinflammatory, analgesic [6], immunostimulatory [7], cardiovascular [8], antimutagenic [9], antimalarial [10], antidiarrheal [11,12], antidiabetic [13], an-tioxidant [14,15], cytotoxic [16], and antimicrobial [15,[17][18][19], have been reported from the extract and essential oil of O. gratissimum. The major compound of the essential oil of O. gratissimum from different regions [15,[19][20][21][22][23][24][25][26][27][28][29][30][31] is represented in Table I. The aim of the present study was to analyze the constituents of essential oil of O. gratissimum growing in a desolate area of South India.…”