Chemical compositions, antimicrobial activity and mosquito larvicidal actions of essential oils from the leaves and fruits of two Rutaceae family of plants from Vietnam

The paper reports that the main constituent of essential oil from the leaves of Macclurodendron oligophlebia (Merr.) Hartl. growing in Vietnam was alpha-pinene (81.7%), while alpha-pinene (67.4%) and limonene (11.2%) were the major compounds in fruit essential oil. The composition of essential oils from the leaves and fruits of Melicope ptelefolia (Champ. ex Benth.) T.G. Hartley was characterized as germacrene D (34.0% and 31.1%, respectively), bicyclogermacrene (5.5% and 7.6%, respectively), d-elemene (9.9% and 9.0%, respectively) and alpha-pinene (6.5% and 9.8%, respectively). The fruit essential oil contains limonene (4.9%) and (E)-beta-ocimene (8.1%). The fruit essential oils of M. oligophlebia and M. ptelefolia exhibited anti-candial activity towards Candida albicans ATCC 10231, with minimum inhibitory concentration (MIC) value of 8.0 mu g/mL and 32.0 mu g/mL, respectively. M. oligophlebia fruit oil also showed action against Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, and Bacillus cereus ATCC 14579, each with MIC value of 32.0 mu g/mL. Also, M. oligophlebia leaf showed higher activity against Pseudomonas aeruginosa ATCC 27853 (MIC, 32.0 mu g/mL). The other oil samples exhibited varying degrees of antimicrobial activity with MIC values of either 64.0 mu g/mL or 128. 0 mu g/mL. The leaf essential oil of M. oligophlebia displayed larvicidal activity against Aedes aegypti larvae with minimum lethal concentration (LC50) values of 16.71 mu g/mL and 11.40 mu g/mL, respectively at 24 h and 48 h. The fruit oil did not exhibit any larvicidal action. However, M. ptelefolia leaf and fruit showed activity at 24 h with LC50 values of 33.18 mu g/mL and 35.06 mu g/mL, respectively.