Essential Oils of Distichochlamys benenica: Chemical Constituents, Mosquito Larvicidal and Antimicrobial Activities

In recent years, essential oils (EOs) have gained popularity for their potential as natural antimicrobial agents and mosquito larvae control. This study aimed to explore the chemical composition of EOs extracted from the leaves and rhizomes of Distichochlamys benenica Q.B. Nguyen & Škorničk, and to evaluate their mosquito larvicidal and antimicrobial activities. The EOs were obtained using hydrodistillation and subjected to gas chromatography (GC) and GC-mass spectrometry to determine their chemical constituents. The main components identified in the leaf EO were β-pinene (47.7%), cis-β-elemene (8.5%), and α-pinene (7.8%), while the rhizome EO mainly consisted of geranyl acetate (25.7%), geranial (23.3%), neral (16.6%), and geraniol (8.4%). The mosquito larvicidal activity of the EOs was evaluated using larvae of Aedes aegypti and Culex quinquefasciatus during 24 and 48 h of treatment. The results demonstrated that these EOs effectively inhibited the mosquito larvae, with LC50 values ranging from 31.15 to 71.53 μg/mL and LC90 values ranging from 46.28 to 148.66 μg/mL. Additionally, the minimum inhibitory concentration (MIC) and half-maximal inhibitory concentration (IC50) values were used to evaluate the antimicrobial efficacy of EOs. Both EOs exhibited potent antimicrobial effects against Enterococcus faecalis ATCC 299212, Staphylococcus aureus ATCC 25923, Bacillus cereus ATCC 14579, Pseudomonas aeruginosa ATCC 27853, and Candida albicans ATCC 10231, with MIC values ranging from 16 to 64 μg/mL and IC50 values ranging from 4.67 to 45.67 μg/mL. Overall, the mosquito larvicidal and antimicrobial activities of D. benenica EOs highlight their potential as natural alternatives for combating mosquito-borne diseases and microbial infections.