Ethnobotanical Leaflets 12: 565-569. 2008. Essential Oil Compounds
and Antibacterial Activity of Leaves of Cinnamomum
chemungianum Mohan et Henry
(Lauraceae) X. Baskaran and M.G. Ebbie Department of Biotechnology Sengunthar Arts and Tiruchengode-637
205, Tamil Nadu, India Email:
baskbiotech@gmail.com Issued Abstract
Essential
oil of leaves of Cinnamomum chemungianum was obtained by hydro distillation and
analyzed by GC-MS. The major components of the oil were Benzyl benzoate
(66.36%), α-Terpine-4-ol (9.83%), Linalool (19.63%), and caryophyllene
oxide (6.6%). Two
compounds of the oils remained unidentified. The in vitro antibacterial activity was performed by agar disc
diffusion method. It showed that maximum inhibition zone activity
against staphylococcus aureus. Keywords: Essential oil, hydro distillation, GC-MS, Antibacterial activity. Introduction Essential oils are valuable natural products used as raw materials in many fields, including perfumes, cosmetics, aromatherapy, phytotherapy, spices and nutrition (Buchbauer, 2000). This has recently attracted the attention of many scientists and encouraged them to screen plants to study the biological activities of their oils from chemical and pharmacological investigations to therapeutic aspects. Hopefully, this will lead to new information on plant applications and new perspective on the potential use of these natural products. Essential oils can be extracted from leaves, flowers, buds, twigs, rhizomes, heartwood, bark, resin, branches or whole plant, seeds and fruits (Sangwan, et al., 2001). The
Lauraceae is a family of about 2000-2200 species of mostly tropical trees (C.
Chaverri and J. F. Ciccio, 2005). The genus Cinnamomum comprises
several hundred species, which occur in Cinnamomum chemungianum Mohan et Henry (Lauraceae) was reported in
1991 from chemungi, Kerala, Materials and methods Collection of plant materials Cinnamomum chemungianum leaves were collected from Kalakad
Mundanthurai Tiger Reserve forest, Hydro-distillation of
essential oil The essential oil was extracted from the collected materials by hydro-distillation for 5 h using the Clevenger type apparatus (Guenther 1948). A clear, yellow coloured oily layer was obtained on top of the aqueous distillate which was separated from the later and dried with the anhydrous sodium sulphate. The extracted essential oil was kept in air tight sealed glass vials and covered with aluminum foil at 4oC until further use. Gas chromatography analysis The essential oil was analyzed using a Shimadzu QP 5000 gas chromatograph equipped with a FID detector and HP-5 MS capillary column (30mx0.25 mm, film thickness 0.25x1m). Injector and detector temperatures were set at 220 and 290 oC, respectively. Oven temperature was kept at 50 oC for 3 min, then gradually raised to 160 oC at 3 oC /min, held for 10 min and finally raised to 240 oC at 3 oC /min. Helium was the carrier gas, at a flow rate of 1 ml/min. Diluted sample (1/100 in acetone, v/v) of 1.0µl was injected manually and in the splitless mode. Quantitative data were obtained electronically from FID area percent data without the use of correction factors. The leaves of C. chemungianum yielded about 1.41% essential oils
which were analyzed by GC/ MS using a Shimadzu – GC 17.A system with OV-I
column (30m\0.25mm; 0.25µm
film thickness). Mass spectra were taken at 70eV. Mass range was from m/z 35-350amu. The column
temperatures were programmed from 70-250 oC at 4 oC /min. Helium was
employed as carrier gas (1ml/min); injection of 1ml of a 1% solution of whole
essential oil in chloroform split Antibacterial activity Bacterial strains Four different bacterial strains used in this study, which were
supplied by Microbial Type Culture Collection and Gene Bank, Institute of
Microbial Technology, Preparation of Inoculums The bacterial strains preserved in the
nutrient agar at 40C were revived in nutrient broth (liquid
medium) and incubated at 37±10C for overnight and the suspensions
were checked to provide approximately 106cfu ml-1. Antimicrobial activity assay The essential oil was
tested for their antimicrobial activity using the disc diffusion technique on
solid media. Sterile 5 mm diameter filter paper discs were impregnated with
20μl of oil extract and placed on nutrient agar seeded with the
microorganisms (106cfu ml-1 ).
The plates were incubated for 24 hrs at 37oC for bacteria. Control
discs were soaked with the same extraction solvents and treated as the sample
discs. The experiments were carried out as duplicate three times and
corrected for the control discs. Additionally, Ampicillin was tested
as positive standards at a concentration of 20μg/disc (Janssen et al., 1987). Results and
discussion Essential
oils of aromatic plant species are used in industry in the production of
perfumes and toiletries. Many of them are also used in traditional medicine
for various purposes and have been screened for their potential uses as
alternative remedies for treatment of many infectious diseases, as food
preservatives, and have shown insecticidal and antiparasitic properties
(Burt. S, 2004). Components
of essential oil The
leaves of C. chemungianum on hyrodistillation
yielded 1.41 % (v/w) essential oil
which was yellow in color. The results of the quantitative analysis are
presented in table 1. The active constituents were
identified by comparisons of their retention time (Rt) and retention indices.
A total of nine constituents were identified. Namely, Benzyl benzoate
(66.36%), α-Terpine-4-ol (9.83%), Linalool (19.63%), and caryophyllene
oxide (6.6%) were found to be the major constituents in the oils of the
leaves. Remaining two
compounds of the oils were unidentified. Antibacterial activity Table 2 summarizes the microbial growth inhibition by
essential oil of leaves of C. chemungianum,
which showed good antibacterial activities against all the tested
organisms. The antibacterial activities of essential oil of Cinnamomum
chemungianum leaves were assayed in-vitro
by agar diffusion method against four bacterial strains. These data
also revealed that the essential oils of leaves of C. chemungianum exhibits strong antibacterial activity. This is used
as a popular ingredient in soaps, perfumes, foods and drinks (Souwalak Phongpaichi et al., 2006). The essential oils of C. chemungianum leaf showed that maximum zone
inhibition active against Staphylococcus aureus. And it also showed
moderate activity against Klebsiella pneumoniae, Pseudomonas
aeruginosa and less activity
studied only against salmonella typhi. According to these
results, it is possible to conclude that C.
chemungianum leaves essential
oil had a strong and a broad spectrum of antibacterial activity and
which may provide to develop novel antibiotics. Acknowledgement The authors grateful to Mr.T. Gunasekaran, References 1. Adams R. P., 2001: Identifications of Essential Oil components by Gas Chromatography / Quadrupole Mass Spectroscopy, 3rd Edition, Allured Publishing Corporation, Illinois, USA, p. 9–40. 2.
Baruah, and Akhil, J.
Essent. Oil Res., (2006), http://findarticles.com/p/articles/mi_qa4091/is_200603/ai_n17182314/print,6/7/2007 3.
Buchbauer G. 2000: The
detailed analysis of essential oils leads to the understanding of their
properties. Perfumer &Flavorist
25: 64–67. 4. Burt S., 2004: Essential oils: their antibacterial properties and potential applications in foods- a review. International journal of Food Microbiology; 94(3): 223-253. 5. Chaverri C. and J. F. Ciccio, 2005: Int. J. Trop. Biol., 53 (3-4): 431-436. 6.
Guenther, E. 1948: The Essential Oils, 1p. 774, 7.
Gupta, S.P., 1977: Statistical
Methods. S. Chand and Co., 8. Janssen, A.M., J.C. Scheffer and A.B. Svendsen, 1987: Antimicrobial activity of essential oils: A 1976- 1986 literature review. Aspects of the test methods. Planta med. 53: 395- 398. 9. Jayaprakasha G. K., L. Jaganmohan Rao and K. K. Sakariah, 2002: Tübingen, 990-993. 10.
Mohan M. and A. N. Henry, 1991: Cinnamomum
chemungianum (Lauraceae) - A new species from Kerala, 11. Sangwan, N. S., Farooqi, A.H.A., Shabih, F., Sangwan, R. S., 2001: Regulation of essential oil production in plant. Plant Growth Regulation 34, 3-21. 12. Souwalak Phongpaichit, Sopa Kummee, Ladda Nilrat and Arunporn Itarat, 2006: Antimicrobial activity of oil from the root of Cinnamomum porectum. Songklanakarin J. Sci. Technol. Vol.29 (Suppl. 1):1-7. 13.
Table-1: Essential oil compositions of Cinnamomum chemungianum leaves.
RT- Retention time; GC- Gas Chromatography;
MS- Mass spectrophotometer Table-2: Antibacterial
activities of essential oil of Cinnamomum chemungianum leaves
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