Fitoterapia 74 (2003) 695–698
Short report
Antimicrobial activity of extractives of Sarcocephalus coadunatus M.R. Khan*, A.D. Omoloso Department of Applied Sciences, Papua New Guinea University of Technology, P.M.B. Lae, Papua New Guinea Received 10 May 2002; accepted 20 May 2003
Abstract The methanolic extracts and the fractions (petrol, dichloromethane, ethyl acetate, butanol) obtained from the leaves, seeds, stem and root barks of Sarcocephalus coadunatus exhibited a high level of broad spectrum antibacterial activity. The activity was more pronounced in the dichloromethane, ethyl acetate and butanol fractions of the leaves; ethyl acetate and butanol fractions of the seeds; dichloromethane fractions of the stem bark and the ethyl acetate fractions of the root bark. None of the fractions showed any antifungal activity. 䊚 2003 Elsevier B.V. All rights reserved. Keywords: Sarcocephalus coadunatus; Antibacterial
Plant. Sarcocephalus coadunatus (Roxb. Ex Sm.) Druce. (Rubiaceae), leaves, seeds, stem and root barks, collected in September 2000, from Goroka in Papua New Guinea (PNG) (plant was supplied by Mr David Kowi, a herbalist from Goroka, in PNG). The plant was identified at the Forestry Department, PNG University of Technology, Lae, where a voucher specimen is deposited. Uses in traditional medicine. Bark used as a febrifuge, tonic, antidiarrheic, for ulcers, toothache, stomachache, leaves as dressing for boils and tumors w1x. *Corresponding author. Tel.: q675-473-4550; fax: q675-473-4558. E-mail address:
[email protected] (M.R. Khan). 0367-326X/03/$ - see front matter 䊚 2003 Elsevier B.V. All rights reserved. doi:10.1016/S0367-326X(03)00157-6
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Table 1 Antimicrobial activity of extractives from Sarcocephalus coadunataa Microorganisms
Seeds
Stem bark
Refb
Root bark
C
P
D
E
B
C
P
D
E
B
C
P
D
E
B
C
P
D
E
B
Chl
Gq Gq Gq Gq Gq Gq Gq Gq Gq Gq Gq Gq Gy
8 8 10 10 14 10 8 8 8 10 10 8 8
14 12 16 10 12 14 16 12 14 14 12 14 12
16 18 18 18 18 16 16 18 18 16 14 18 18
16 16 18 14 18 16 16 18 14 18 18 18 14
16 16 18 18 20 18 18 20 18 16 16 20 18
12 10 10 12 10 10 10 12 12 10 10 12 10
12 14 14 16 14 14 16 18 14 16 14 14 16
12 14 16 16 14 12 12 12 16 18 12 12 16
16 18 18 16 18 18 16 18 18 18 18 18 18
18 18 18 18 20 18 18 18 18 18 20 18 18
10 10 10 12 10 12 10 8 12 12 10 8 10
10 10 8 10 12 10 14 10 10 10 14 12 10
14 16 18 18 18 18 16 16 18 18 14 18 18
10 14 14 16 14 14 10 12 16 16 10 12 14
14 16 14 16 16 14 14 16 14 16 14 14 16
14 16 16 14 14 16 14 14 16 14 14 12 10
10 12 10 12 14 14 14 12 10 10 10 14 14
10 12 8 8 10 10 10 12 8 10 10 12 8
16 16 18 18 14 18 18 16 14 16 18 18 18
16 16 16 16 18 16 20 16 18 16 20 18 16
16 18 16 16 18 16 6 16 18 0 0 18 12
Gy Gy
10 8
10 12
18 18
14 18
16 18
10 10
16 14
16 14
18 16
16 16
12 12
10 10
18 18
18 16
16 16
14 10
10 12
10 12
18 18
16 18
16 18
Gy Gy Gy
12 8 8
10 14 10
16 16 18
18 16 18
18 18 20
10 12 10
16 18 14
16 12 16
18 18 18
18 18 20
10 10 10
14 14 10
16 18 16
16 12 14
14 18 14
14 14 16
12 10 14
12 10 10
16 14 16
14 16 14
18 0 18
Gy Gy Gy
10 10 8
12 14 12
18 16 18
18 18 16
20 18 18
10 12 10
16 16 14
16 16 12
18 16 18
18 18 18
12 10 12
10 12 12
18 18 18
14 14 12
16 14 16
14 14 14
14 14 10
12 8 10
18 18 18
18 20 16
16 18 24
Gy Gy Gy Pz
12 8 10 10
14 12 14 14
14 16 18 16
18 18 16 16
18 16 18 18
10 8 12 10
16 14 18 16
14 14 14 16
18 18 18 18
18 16 18 18
12 10 10 10
10 10 12 10
16 14 18 18
14 14 12 14
14 14 16 16
16 12 14 14
12 10 14 10
12 12 12 12
18 18 16 18
18 16 16 18
16 16 0 16
a Values are inhibition zone (mm) and an average of triplicate. C: unfractionated methanol extract; P: petrol (60–80 8C) fraction; D: CH2 Cl2 fraction; E: EtOAc fraction; B: butanol fraction (concentration 4 mgydisc), G: Gram reaction of bacterium; Pz: protozoan. b Chl, chloramphenicol (10 mg disc Oxoid B42960).
M.R. Khan, A.D. Omoloso / Fitoterapia 74 (2003) 695–698
Bacillus cereus B. coagulans B. megaterium B. subtilis Lactobacillus casei Micrococcus luteus M. roseus Staphylococcus albus S. aureus S. epidermidis Streptococcus faecalis St. pneumoniae Agrobacterium tumefaciens Citrobacter freundii Enterobacter aerogenes Escherichia coli Klebsiella pneumonia Neisseria gonorrhoeae Proteus mirabilis P. vulgaris Pseudomonas aeruginosa Salmonella typhi Sa. typhymurium Serratia marcescens Trichomonas vaginalis
Leaves
M.R. Khan, A.D. Omoloso / Fitoterapia 74 (2003) 695–698
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Previously isolated classes of constituents. Bitter dye and alkaloid w1x. Tested material. The MeOH Soxhlet extracts of dried plant material (leaves, seeds, stem bark, root bark; yields: 34.4, 24.5, 21.2 and 26.2%, respectively), with petrol (P) (60–80 8C), CH2Cl2 (D), EtOAc (E) and butanol (B). Yields (%) and positive tests on phytochemical screening w2x. Leaves: P (1.24; flavonoids, saponins, tannins), D (0.28; flavonoids, saponins, sterols, tannins, triterpenoids), E (4.37; flavonoids, saponins, sterols, tannins, triterpenoids), B (2.71; flavonoids, saponins, tannins); seeds: P (4.19; alkaloids, flavonoids, saponins, tannins), D (0.97; sterols, triterpenoids), E (1.06; flavonoids, saponins, tannins), B (13.82, flavonoids, saponins, tannins); stem bark: P (0.63; alkaloids, flavonoids, sterols, tannins, triterpenoids), D (1.21; alkaloids, flavonoids, sterols, triterpenoids), E (1.94; flavonoids, saponins, sterols, tannins, triterpenoids), B (1.67; flavonoids, saponins, tannins); root bark: P (3.84; flavonoids, saponins, tannins), D (0.21; flavonoids, saponins, sterols, tannins, triterpenoids), E (1.65; flavonoids, saponins, sterols, tannins, triterpenoids), B (3.74; flavonoids, saponins, tannins). Studied activity. Antimicrobial activity by the disk diffusion method w3,4x. Used microorganisms. Bacteria, protozoan (listed in Table 1) and fungi (Aspergillus niger, A. rubrum, A. versicolor, A. vitis, Candida albican, C. tropicalis, Cladosporium cladosporiods, Trychophyton mentagrophytes, T. tronsurum) were obtained from the stock cultures of the Microbiology Laboratory, Department of Applied Sciences, Lae. Results. Antibacterial activity is reported in Table 1. None of the extractives showed any antifungal activity. Conclusions. All fractions showed a very good level of broad spectrum antibacterial activity. As compared to the unfractionated crude extracts, partitioning drastically improved the activity. Particularly good activity was observed in the dichloromethane, ethyl acetate and butanol fractions of the leaves; ethyl acetate and butanol fractions of the seeds; dichloromethane fractions of the stem bark and the ethyl acetate fractions of the root bark. None of the fractions demonstrated antifungal activity. Acknowledgments The authors are grateful to Mr J. Simaga of the Forestry Department, for the identification of the plant.
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References w1x Perry LM. Medicinal plants of East and Southeast Asia: attributed properties and uses. Cambridge, Massachusetts, and London: The MIT Press, 1980. p. 358. w2x Harborne JB. Phytochemical methods. 2 ed. London–New York: Chapman and Hall, 1984. w3x Cruickshank R. 11 ed. Medical microbiology: a guide to diagnosis and control of infection. Edinburgh and London: E. and S. Livingston Ltd, 1968. p. 888. w4x Bauer AW, Kirby WMM, Sherries JC, Truck M. Am J Clin Pathol 1966;45:493.