Chemical Compositions, Mosquito Larvicidal and Antimicrobial Activities of Essential Oils from Five Species of Cinnamomum Growing Wild in North Central Vietnam

Abstract

Members of the genus Cinnamomum (Lauraceae) have aromatic volatiles in their leaves and bark and some species are commercially important herbs and spices. In this work, the essential oils from five species of Cinnamomum (C. damhaensis, C. longipetiolatum, C. ovatum, C. polyadelphum and C. tonkinense) growing wild in north central Vietnam were obtained by hydrodistillation, analyzed by gas chromatography and screened for antimicrobial and mosquito larvicidal activity. The leaf essential oil of C. tonkinense, rich in β-phellandrene (23.1%) and linalool (32.2%), showed excellent antimicrobial activity (MIC of 32 μg/mL against Enterococcus faecalis and Candida albicans) and larvicidal activity (24 h LC50 of 17.4 μg/mL on Aedes aegypti and 14.1 μg/mL against Culex quinquefasciatus). Cinnamomum polyadelphum leaf essential oil also showed notable antimicrobial activity against Gram-positive bacteria and mosquito larvicidal activity, attributable to relatively high concentrations of neral (11.7%) and geranial (16.6%). Thus, members of the genus Cinnamomum from Vietnam have shown promise as antimicrobial agents and as potential vector control agents for mosquitoes.

Chemical composition, insecticidal and biochemical effects of two plant oils and their major fractions against Aedes aegypti, the common vector of dengue fever

“…Many reports proved that the activity of plant EOs could be correlated to the presence of several components with demonstrated insecticidal activities, such as α-terpinene, α-pinene, p-cymene, β-caryophyllene, thymol and carvacrol ( Shaalan et al., 2005 ; Dai et al., 2020 ), although synergism with other minor constituents has to be taken into consideration, as each oil fraction can play a role in penetration, affinity and distribution within living cells. Accordingly, for biological efficacy, it is more appropriate to investigate the entire oil and some of its major components, as synergistic interaction between the essential oil fractions becomes a common phenomenon ( Nenaah, 2014a , b ).…”

Mosquito Larvicidal Activity, Antimicrobial Activity, and Chemical Compositions of Essential Oils from Four Species of Myrtaceae from Central Vietnam

“…Mosquito colonies of Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus were obtained and maintained as previously described [82].…”

“…The antimicrobial activity of the essential oils was evaluated using two bacteria (Enterococcus faecalis, ATCC 299212, and Staphylococcus aureus, ATCC 25923) and one yeast (Candida albicans, ATCC 10231) using the microdilution broth susceptibility assay, as previously reported [82]. Stock solutions of the each of the essential oils were prepared in dimethylsulfoxide.…”

Premna Species in Vietnam: Essential Oil Compositions and Mosquito Larvicidal Activities

“…Larvicidal activities of the Premna essential oils were determined following the protocol previously reported [ 62 ]: 250-mL beakers, 150 mL of water, and 20 larvae (fourth instar), aliquots of the Premna essential oils dissolved in EtOH (1% stock solution) were added to give final concentrations of 100, 50, 25, 12.5, and 6 μg/mL; EtOH only (negative control) and permethrin (positive control), mortality recorded after 24 h and 48 h of exposure, experiments were carried out at 25 ± 2 °C, each test was conducted with four replicates. The data obtained were subjected to log-probit analysis [ 63 ] to obtain LC 50 values, LC 90 values and 95% confidence limits using Minitab ® 19 (Minitab, LLC, State College, PA, USA).…”