title: Antibacterial activity of leaf essential oil and its constituents from Cinnamomum longepaniculatum.
abstract: Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922 and Salmonella enteritidis CMCC (B) 50041, were used in the antibacterial tests of Cinnamomum longepaniculatum leaf essential oil and its five chemical constituents. The effect of 1, 8-cineole on the ultrastructural structure of the bacteria (S. aureus and E. coli) was also investigated by transmission electron microscopy. The C. longepaniculatum leaf essential oil and the five chemical constituents showed variable levels of inhibition. Their MIC ( minimum inhibitory concentration ) and MBC (minimal bacteriocidal concentration) values were all in the range of 0.781 µL/mL~6.25 µL/mL and 0.781 µL/mL~12.5 µL/mL respectively except γ-terpinene. The MIC values of γ-terpinene against E. coli and S. aureus were all higher than 50 µL/mL, but the MIC and MBC values of γ-terpinene against S. enteritidis was only 3.125 µL/mL. Among them, α-terpineol possessed the best antibacterial activity. Under the transmission electron microscope, cell size of treated E. coli decreased, cell wall and cell membrane ruptured, and nucleoplasm was reduced and gathered onto the side. After the S. aureus was treated with 1, 8-cineole, the cell size and shape were damaged and nucleus cytoplasm was concentrated or reduced or agglomerated on the side. These results suggest that C. longepaniculatum leaf essential oil and its constituents have excellent antibacterial activities, the antibacterial mechanism of 1, 8-cineole against E. coli and S. aureus might attributable to its hydrophobicity.
authors.affiliation: College of Veterinary Medicine Sichuan Agricultural University Ya'an, 625014, China.
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.affiliation: College of Veterinary Medicine Sichuan Agricultural University Ya'an, 625014, China.
authors.forename: Zheng-Wen
authors.initials: ZW
authors.lastname: Li
authors.affiliation: College of Veterinary Medicine Sichuan Agricultural University Ya'an, 625014, China.
authors.forename: Zhong-Qiong
authors.initials: ZQ
authors.lastname: Yin
authors.affiliation: Key Lab of Aromatic Plant Resources Exploitation and Utilization in Sichuan Higher Education, Yinbin College Yin'bin, 644000, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Wei
authors.affiliation: College of Veterinary Medicine Sichuan Agricultural University Ya'an, 625014, China.
authors.forename: Ren-Yong
authors.initials: RY
authors.lastname: Jia
authors.affiliation: Key Lab of Aromatic Plant Resources Exploitation and Utilization in Sichuan Higher Education, Yinbin College Yin'bin, 644000, China.
authors.forename: Li-Jun
authors.initials: LJ
authors.lastname: Zhou
authors.affiliation: College of Veterinary Medicine Sichuan Agricultural University Ya'an, 625014, China.
authors.forename: Jiao
authors.initials: J
authors.lastname: Xu
authors.affiliation: College of Veterinary Medicine Sichuan Agricultural University Ya'an, 625014, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Song
authors.affiliation: College of Veterinary Medicine Sichuan Agricultural University Ya'an, 625014, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Key Lab of Aromatic Plant Resources Exploitation and Utilization in Sichuan Higher Education, Yinbin College Yin'bin, 644000, China.
authors.forename: Yong-Hua
authors.initials: YH
authors.lastname: Du
authors.affiliation: College of Veterinary Medicine Sichuan Agricultural University Ya'an, 625014, China.
authors.forename: Lian-Ci
authors.initials: LC
authors.lastname: Peng
authors.affiliation: College of Veterinary Medicine Sichuan Agricultural University Ya'an, 625014, China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Kang
authors.affiliation: Key Lab of Aromatic Plant Resources Exploitation and Utilization in Sichuan Higher Education, Yinbin College Yin'bin, 644000, China.
authors.forename: Wang
authors.initials: W
authors.lastname: Yu
keywords: 1; 8-cineole; Cinnamomum longepaniculatum; antimicrobial activity; essential oil; transmitted electron microscopy