Skip to content

Advertisement

You're viewing the new version of our site. Please leave us feedback.

Learn more

BMC Research Notes

Open Access

Anti-Staphylococcus aureus activity of methanol extracts of 12 plants used in Cameroonian folk medicine

  • Leonard Sama Fonkeng1,
  • Raymond Simplice Mouokeu2,
  • Christopher Tume1Email author,
  • Guy Sedar Singor Njateng1,
  • Monique Odette Kamcthueng1,
  • Nfozon Jinette Ndonkou1 and
  • Jules-Roger Kuiate1
BMC Research Notes20158:710

https://doi.org/10.1186/s13104-015-1663-1

Received: 7 May 2015

Accepted: 2 November 2015

Published: 24 November 2015

Abstract

Background

The emergence of bacterial infections including those associated with Staphylococcus aureus causes a benefit of interest to medicinal plants as an effective means of control. The present study was designed to investigate the activities of 12 selected Cameroonian medicinal plants against S. aureus isolates.

Methods

The plant extracts were prepared by maceration in methanol at laboratory temperature. Qualitative phytochemical analysis was performed by chemical reaction methods. The broth microdilution method was used to evaluate the activities of plant extracts against 11 S. aureus clinical isolates.

Results

Dacryodes edulis was found to have significant antibacterial activity on all the S. aureus isolates (MIC = 64–256 µg/ml). Occimum gratissimum revealed significant inhibitory activity on 9 of the 11 isolates while Commelina erecta and Spilanthes filicaulis revealed similar results on 6 of the 11 clinical isolates.

Conclusion

The present findings showed that D. eduli, O. gratissimum, C. erecta and S. filicaulis possess interesting inhibitory properties against S. aureus species. These plants could therefore be good candidates to overcome infectious diseases associated with these microorganisms.

Keywords

Medicinal plant Staphylococcus aureus Antibacterial activityCameroonian folk medicine

Background

Infectious diseases are becoming a major cause of human and animal mortality and morbidity. This is further aggravated by the rapid development of multi-drug resistance, limited antibacterial spectrum and adverse effects of available antimicrobial agents [1]. Human pathogenic bacteria include amongst others Staphylococcus aureus; a major cause of bacteremia, associated with higher morbidity and mortality compared to other bacteremia-causing pathogens [2]. The burden of S. aureus bacteremia, particularly methicillin-resistant S. aureus bacteremia is due to the fact that, it is highly expensive in terms of cost and resource. The incidence of S. aureus bacteremia and its complications has increased abruptly in recent years because of the increased frequency of invasive procedures which has led to great number of immunocompromised patients and resistance of S. aureus strains to available antibiotics. This changing epidemiology of S. aureus bacteremia, in combination with the inherent virulence of the pathogen, is commanding an urgent need for improved strategies and better antibiotics to prevent and treat S. aureus bacteremia [3, 4].

The investigation of certain indigenous plants for their antimicrobial properties may yield useful results. This has consequently increased the attention and demand given to antimicrobials derived from the plants [5]. Natural products, either as pure compounds or as standardized plant extracts, provide exceptional opportunities for new drug leads because of the unmatched chemical diversity of naturally derived compounds [6, 7]. The medicinal value of plants is associated with some chemical substances also known as phytochemicals that produce a definite physiological action on humans. The present study was designed to investigate the activities of 12 selected Cameroonian medicinal plants against S. aureus clinical isolates.

Methods

Collection and identification of plant samples

Twelve plant samples were used in this study. They were collected either from Santchou or Dschang in April 2011, Menoua division, West Region of Cameroon. The taxonomical authentication of identity was undertaken by a botanist at the National Herbarium of Cameroon in Yaounde where voucher specimens were deposited. For each plant, the part used, the identification code, previous studies and ethnobotanical surveys are presented in Table 1.
Table 1

Information on the plants used, yields of extraction and report on evidence of their activities

Plant name

Parts use tradionally

Locality of harvest

Yields (%)

Ethnobotanical relevance

Identification code

Previous scientific studies

Acalypha frutucosa Forssk

Leaf

Santchou

3.43

Skin infections and diarrhoea

33,034/HNC

Antimicrobial and antioxidant activity [8]

Aspilia africana CD/Adams

Leaf

Santchou

2.51

Wound treament

16,935/SRF Cam

Antiulcer activity [9]

Commelina Erecta

Leaf

Santchou

1.56

Eczema and skin infection treatment

22,595/SRF Cam

/

Dacryodes edulis (Don) H.J Lam

Leaf

Santchou

4.44

Stomach ache

17,234/SRF Cam

Phytochemical studies and antimicrobial activity [10]

Drymaria cordata Willd

 

Dschang

1.02

Headache

20,550/SRF Cam

Cytotoxic activity [11]

Eremomastax speciosa Cufod

Leaf

Dschang

2.26

Nappy rash treatment

36,228/HNC

Antidiarrhoea and antimicrobial activity [12, 13]

Kalanchoe crenata Andr

Leaf

Santchou

10.92

Ear infection, rheumatism and inflammatory treatment

50,103/YA Cam

anti-inflamatory and antibacterial activity [14, 15]

Occimum gratissimum linn Hochst

Leaf

Santchou

9.54

Food plant

42,850/HNC

Antimicrobial and phytochemical studies [16, 17]

Portulaca oleracea

Leaf

Dschang

4.61

Food plant

17,542/SRF Cam

Antimicrobial and phytochemical studies [18]

Scoporia dulcis Linn

Leaf

Santchou

8.12

Stomach ache

22,595/SRF Cam

Antidiabetic activity [19]

Sida veronicifolia Linn

Leaf and steam

Santchou

1.11

Stomach ache

20,859/SRF Cam

Antioxydant activity [20]

Spilanthes filicaulis C .D. Adams

Leaf and steam

Santchou

5.54

Headache, fontanel, teeth pain, angina

20,447/SFR Cam

Phytochemical studies and antiulcer activity [9]

Preparation of plant extracts and preliminary qualitative phytochemical screening

The leaves or the stems of each plant were air-dried at room temperature (20 ± 4 °C) before grinding to powder with a mechanical grinder. The powder (150 g) was macerated in methanol (300 ml) for 4 days with a three times daily shaking, the mixture was then filtered using Whatmann filter paper No. 1. The filtrate was concentrated at 50 °C under reduced pressure using a rotary evaporator (Buchi R-200) and further dried using a vacuum concentrator (SC250EXP).

The qualitative phytochemical analysis was performed following standard methods [21].

Microorganisms

A total of 11 clinical isolates of S. aureus were used. They were isolated locally on Mannitol salt agar slant (Conda, Madrid, Espagne) from patients with urogenital infections. The species was confirmed following morphological observations and biochemical tests [22]. These micro-organisms were maintained in agar slants.

Antimicrobial susceptibility testing

Luria–Bertani agar (Himedia, India) was used for the upkeeping of the isolates, whereas Luria–Bertani broth (LBB) was used for antimicrobial susceptibility testing using broth microdilution method.

The antibacterial activity was investigated by determining the minimum inhibitory concentrations (MICs) and the minimum bactericidal concentrations (MBCs). The MICs value of the plant extracts were determined using a rapid p-Iodonitrotetrazolium (INT) chloride (Sigma-Aldrich, France) colorimetric assay [23]. Briefly, stock solutions of plant extracts were prepared in 5 % (v/v) dimethylsulfoxide (DMSO) solution (Fisher chemicals, France). The solution obtained was then diluted with LBB (Himedia, India) to give a final concentration of 4096 µg/ml. 100 ml of each extract solution was introduced into the first three wells of 96-wells microtitre plate containing 100 µl of LBB and further twofold serially diluted to obtain concentrations ranging from 1024 to 8 µg/ml. 100 ml of bacterial suspensions of about 1.5 × 108 CFU/ml following Mc Farland turbidity standard no. 0.5, 100 times diluted, were introduced into each well containing 100 µl mixture of LBB and extract. The final concentration of DMSO was less than 1 %. Wells containing LBB, inoculum and DMSO at a final concentration of 1 % served as the negative control. Ciprofloxacin (Sigma-Aldrich, France) was used as reference antibiotic. The plates were covered with a sterile plate sealer and then agitated with a shaker. They were further incubated at 35 °C for 24 h. Upon incubation, 40 µl of 2 % INT solution were added in each well. Viable bacteria reduced the yellow dye of INT to pink. All the concentrations that did not show color change were considered, and the smallest was noted as MIC value of each extract on the isolate.

For the well that did not received INT, 50 µl of solution of the corresponding well that did not present color change was withdrawn out and seeded into the wells of new plates containing 150 µl of newly LBB prepared. The mixture was further incubated at 35 °C for 48 h. After the incubation period, 40 µl of INT solution were introduced in each well. The MBCs were considered as the lowest concentration of the extract that prevents INT color change [23].

Results

Qualitative phytochemical composition

Freshly prepared extracts were subjected to phytochemical screening for various constituents. The results revealed the presence of Phytochemical compounds including alkaloids, anthocyanins, anthraquinones, flavonoids, phenols, tannins and triterpenes (Table 2). Only Dacryodes edulis extract was found to contain saponins.
Table 2

Qualitative phytochemical composition of the plant extracts

 

A. africana

A. frutucosa

C. erecta

D. cordata

D. edulis

E. speciosa

K. crenata

O. gratissimun

P. oleracea

S. dulcis

S. filicaulis

S. veronicifolia

Phenols

+

+

+

+

+

+

+

+

+

+

Saponins

+

Tannins

+

+

+

+

Flavonoids

+

+

+

+

+

+

+

+

+

Anthraquinones

+

+

+

Anthocyanins

+

+

+

+

+

+

+

+

Alcaloids

+

+

+

+

+

Sterols

+

+

+

+

+

+

+

+

Triterpenes

+

+

+

+

+

+

+

+

+ present; – absent

Antibacterial activity

The antibacterial activities of the 12 plant extracts on S. aureus isolates are presented in Table 3. D. edulis and Occimum gratissimum with MIC values ranging from 64–256 µg/ml were found to have the best inhibitory activity on almost all the tested microorganisms. Scoparia dulcis, Spilanthes filicaulis, Commelina erecta and E. spciosa with MIC = 64–512 µg/ml were found to have similar antibacterial activity, being more active compared to Kalanchoe crenata (MIC = 512–1024 µg/ml). Aspilia africa, Drymaria cordata, Portulaca oleracea and Sida veronicifolia were almost inactive on these microorganisms.
Table 3

Minimal inhibitory concentrations and minimal bactericidal concentrations (µg/ml) of plant extracts against Staphylococcus aureus isolates

 

Staph 23 JN

Staph 55 M

Staph 67 JN

Staph 18 JL

Staph 79 M

Staph 58 M

Staph 22 JN

Staph 70 M

Staph 02 JN

Staph

94 M

Staph

75 N

A. africa

 CMI

>1024

>1024

>1024

>1024

>1024

>1024

>1024

>1024

>1024

>1024

>1024

 CMB

/

/

/

/

/

/

/

/

/

/

/

 CMB/C MI

/

/

/

/

/

/

/

/

/

/

/

A. frutucosa

 CMI

>1024

512

>1024

>1024

>1024

>1024

>1024

>1024

>1024

512

>1024

 CMB

/

1024

/

/

/

/

/

/

/

1024

/

 CMB/CMI

/

2

/

/

/

/

/

/

/

2

/

C. erecta

 CMI

>1024

128

256

128

256

256

512

512

512

256

512

 CMB

/

1024

512

512

>1024

512

>1024

>1024

1024

512

>1024

 CMB/CMI

/

8

2

4

/

2

/

/

2

2

/

D. cordata

 CMI

>1024

>1024

512

512

>1024

512

>1024

>1024

>1024

>1024

>1024

 CMB

/

/

>1024

>1024

/

>1024

/

/

/

/

 

 CMB/CMI

/

/

/

/

/

/

/

/

/

/

 

D. edulis

 CMI

256

256

128

64

64

256

256

256

128

128

256

 CMB

512

512

256

256

128

1024

1024

1024

256

256

1024

 CMB/CMI

2

2

2

4

2

4

4

4

2

2

4

E. speciosa

 CMI

>1024

256

512

64

256

256

512

256

512

256

512

 CMB

/

1024

1024

128

512

512

1024

>1024

>1024

1024

>1024

 CMB/CMI

/

4

2

2

2

2

2

/

/

4

/

K. crenata

 CMI

256

512

256

256

256

512

>1024

>1024

128

128

256

 CMB

512

>1024

512

1024

1024

1024

/

/

256

256

512

 CMB

2

/

2

4

4

2

/

/

2

2

2

O. gratissimum

 CMI

256

128

256

128

256

256

256

512

512

64

128

 CMB

512

256

1024

512

512

512

512

>1024

1024

128

256

 CMB/CMI

2

2

4

4

2

2

2

 

2

2

2

P. oleracea

 CMI

>1024

512

512

>1024

>1024

>1024

>1024

>1024

>1024

512

>1024

 CMB

/

1024

1024

/

/

/

/

/

/

1024

/

 CMB/CMI

/

2

2

/

/

/

/

/

/

2

/

S. dulcis

 CMI

512

256

512

512

>1024

512

512

512

512

128

256

 CMB

>1024

512

>1024

>1024

 

1024

>1024

>1024

1024

256

1024

 CMB/CMI

 

2

   

2

  

2

2

4

S. filicaulis

 CMI

512

256

256

512

256

512

>1024

256

512

128

256

 CMB

1024

1024

512

>1024

512

1024

/

1024

>1024

256

512

 CMB/CMI

2

4

2

/

2

2

/

4

 

2

2

S. veronicifolia

 CMI

512

>1024

>1024

>1024

>1024

>1024

>1024

>1024

>1024

128

>1024

 CMB

1024

/

/

/

/

/

/

/

/

512

/

 CMB/CMI

2

/

/

/

/

/

/

/

/

4

/

Ciprofloxacine

 CMI

1,25

0.625

2.5

1.25

2.5

5

1.25

0.312

0.625

1.25

0.625

 CMB

5

0.625

2.5

5

2.5

5

5

1.25

5

1.25

1.25

 CMB/CMI

4

1

4

1

1

4

4

8

8

1

2

Staph: Staphylococcus aureus, / no activity

Considering all the inhibitory activity, MICs values of all the active plant extracts were almost fourfold less than their MBCs values.

Discussion

The plants selected in this study are all used in Cameroonian traditional medicine to overcome a wide range of diseases. Ethno-pharmacological data have confirmed their role in health maintenance and promotion, but the major challenge is either to provide scientific evidence or to produce complementary data of their previous well established antibacterial properties.

Each of the extract of D. edulis, O. gratissimum, S. dulcis, S. filicaulis, C. erecta and E. spciosa tested in the present study displayed antibacterial activity on bacterial isolates tested. This evidence emphasizes the role of ethnopharmacological data as a framework for the discovery of bioactive compounds from plants.

Antimicrobial activity of plant extracts are routinely classified on the basis of susceptibility tests that produce MICs values in the range of 500–1500 μg/ml [24]. The activity is considered to be significant if MICs values are below 500 μg/ml and moderate when the MICs vary from 500 to 1500 μg/ml. Based on this scale, D. edulis was found to have significant antibacterial activity on all the 11 S. aureus isolates. O. gratissimum revealed similar activity on nine of the 11 isolates while C. erecta and S. filicaulis revealed similar results on 6 of the 11 clinical isolates. In general, MBC/MIC ratios less than or equal to four signifies a bactericidal effect of the test substance [15]. This indicates that the bactericidal effect of the active plant extracts could be expected.

Previous studies on the antibacterial activity of the essential oil of Lippia sidoides on clinical isolates of S. aureus had revealed a much important activity compared to other plants (MIC 400 µl/ml) [25]. The above plant extracts have proven much higher activities. Therefore these plants could be good candidates to overcome infectious diseases associated with S. aureus. These results are relevant since this microorganism is one of the most important human pathogens associated with hospital and community-acquired infections. Over the last few decades, the number and proportion of methicillin-resistant S. aureus infections in different countries has increased due to the rise of epidemics in humans [2, 26] and other animals, such as dogs, cats, cattle, pigs and exotic species [27].

Dacryodes. edulis and O. gratissimum activity are in accordance with previous work. Indeed, significant antibacterial activity of these plants on many bacterial species including S. aureus is well documented [10, 2831]. Nevertheless, the real extend of this previous antibacterial results could not be compared to the present finding since the agar diffusion tests were performed.

The antibacterial activity of S. dulcis [32], S. filicaulis [33] and K. crenata [20] was earlier reported on Gram negative and Gram positive bacteria including S. aureus. Except K. crenata extract which revealed similar weak activity on S. aureus [15]. It was difficult to compare the limit as earlier mentioned. The present findings are therefore additional data that support the antibacterial activity of these plants as potent candidates to overcome infections associated with bacteria including S. aureus. To the best of our knowledge, the antibacterial activity of C. erecta and particularly on S. aureus is reported here for the first time.

The phytochemical screening was in accordance with reported data but slight differences were noted [15, 30, 3436]. The phytochemical groups found in these extract could explain the antibacterial activity observed as well as the differences since the secondary metabolites of plants have many effects including antimicrobial properties [37]. Moreover, the differences could be attributed mainly to the chemical reaction method commonly used to identify the phytochemical groups of constituents. In fact, plant extracts are usually colored and this may mask specific color of some particular phytochemical group. The origin of the plant materials and the nature of the solvent for extraction are other factors that may affect the composition. Moreover, the distribution of these phytochemical groups varied from one organ to another.

Conclusion

The present finding showed that D. eduli, O. gratissimum, C. erecta and S. filicaulis possess interesting inhibitory properties against S. aureus species. These data are promising and could encourage further researches on phytochemical, toxicological and pharmacological aspects of these extract-products in order to support their possible rational use in antimicrobial therapy, particularly, in anti-S. aureus therapy.

Abbreviations

MIC: 

minimal inhibitory concentrations

MBC: 

minimal bactericidal concentrations

DMS: 

dimethylsulfoxide

INT: 

iodonitrotetrazolium chloride

Declarations

Authors’ contributions

LFS is the field investigator; RSM is the co-field investigator and conceive the manuscript, TC design the study and supervised the work, MOK contributed in the lab work and also revised the manuscript GSSN revised the manuscript, JNN contributed in the lab work, JRK supervised the work and revised the manuscript. All authors read and approved the final manuscript.

Acknowledgements

Authors acknowledge the National Herbarium of Yaoundé, Cameroon for plant identification.

Competing interests

The authors declared that they have no competing interests.

Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

Authors’ Affiliations

(1)
Laboratory of Microbiology and Antimicrobial Substances, Faculty of Science
(2)
Institute of Fisheries and Aquatic Sciences, University of Douala

References

  1. Doughart JH, Okafor B. Anti-microbial activity of Senna alata linn. East and Central. Afr J Pharm Sci. 2007;10:17–21.Google Scholar
  2. Lee AS, Huttner B, Harbarth S. Control of methicillin-resistant Staphylococcus aureus. Infect Dis Clin North Am. 2011;25:155–79.View ArticlePubMedGoogle Scholar
  3. Naber CK. Staphylococcus aureus Bacteremia: epidemiology, pathophysiology, and management strategies. Clin Infect Dis. 2009;48:231–7.View ArticleGoogle Scholar
  4. Zriouil SB, Bekkali M, Zerouli K. Epidemiology of Staphylococcus aureus infections and nasal carriage at the Ibn Rochd University hopistal Center, Casablanca, Morocco. Braz J Infect Dis. 2012;16(3):279–83.View ArticlePubMedGoogle Scholar
  5. Akgul C, Saglikoglu G. Antibacterial activity of crude methanolic extract and its fractions of aerial parts of Anthemis tinctoria. Indian J Biochem Biophys. 2005;42:395–7.PubMedGoogle Scholar
  6. Mariita RM, Ogol CKP, Oguge NO, Okemo PO. Antitubercular and phytochemical investigation of methanol extracts of medicinal plants used by the Samburu Community in Kenya. Trop J Pharm Res. 2010;9:379–85.View ArticleGoogle Scholar
  7. Ngoci SN, Mwendia CM, Mwaniki CG. Phytochemical and cytotoxicity testing of Indigofera lupatana Baker F. J Anim Plant Sci. 2011;11:1364–73.Google Scholar
  8. Mothana RAA, Abdo SAA, Hasson S, Althawab FMN, Alaghbari SAZ, Lindequist U. Antimicrobial, antioxidant and cytotoxic activities and phytochemical screening of some yemeni medicinal plants. Evid Based Complement Alternat Med. 2010;6(3):36–49.Google Scholar
  9. Ubaka MC, Ukwe VC, Okoye CT, Adibe OM. Investigation into the anti-ulcer activity of the aqueous leaf extract of Aspilia africana C.D. Adams. Asian J Med Sci. 2010;2(2):40–3.Google Scholar
  10. Ajibesin KK. Dacryodes edulis (G. Don) H.J. Lam: A review on its medicinal. Phytochemical and economical medicinal plant. Res J Med Plant. 2011;5(1):32–41.View ArticleGoogle Scholar
  11. Sowemimo A, Maryna VV, Baatjies L, Koekemoer T. Cytotoxicity evaluation of selected Nigerian plants used in traditional cancer treatment. J Med Plants Res. 2011;5(11):2442–4.Google Scholar
  12. Julius E, Oben S, Asi E, Agbor GA, Musoro DF. Antimicrobial effects of Thai medicinal plants against acne-inducing bacteria. J Ethnopharmacol. 2006;101:330–3.Google Scholar
  13. Okokon JE, Antia BS, Udoh AE, Akpan MM. Antianaemic and antimicrobial activity of Eremomastax speciosa. J Pharmacol Toxicol. 2007;2:196–9.View ArticleGoogle Scholar
  14. Dimo T, Nguelefack TB, Fotio AL, Emmanuel A, Asongalem PKT. Antiinflammatory activity of leaf extracts of Kalanchoe crenata Andr. Indian J Pharmacol. 2004;38:115–9.View ArticleGoogle Scholar
  15. Yimta F, Mouokeu RS, Nguimatsia F, Njateng GSS, Tamokou JDD, Kuiate JR: Antibacterial activity of methanol extracts and fractions from Kalanchoe crenata, Terminalia avicennioides and Sarcocephallus latifolius. Pharmacologia 2014, 199–204.Google Scholar
  16. Apinya P, Udomsilp J, Khang-Khun P, Thobunluepop P: Evaluation of potential antimicrobial activity of some medicinal plants against common food-borne pathogenic microoganisms. Asian Journal of Food and Agro-Industry, 2009, 2–9.Google Scholar
  17. Mbata TI, Lu Debiao Saikia A. Antibacterial activity of the crude extract of Chinese green tea. Int J Microbiol. 2009;2(2):1–6.Google Scholar
  18. Bakkiyaraj S, Pandiyara S, Avadi V. Evaluation of potential antimicrobial activity of some medicinal plants against common food-borne pathogenic microoganism. Int J Pharma Bio Sci. 2011;2(2):484–91.Google Scholar
  19. Saikia R, Choudhur MD, Talukdar AD, Pankaj C. Antidiabetic activity of ethno medicinal plant Scoparia dulcis L. (Family: Scrophulariaceae): a review. Assam Univ J Sci Technol. 2011;7(1):173–80.Google Scholar
  20. Franzotti EM, Santos CV, Rodrigues HM, Mourão RH, Andrade M, Antoniolli A. Anti-inflammatory, analgesic activity and acute toxicity of Sida cordifolia L. (Malva-branca). J Ethnopharmacol. 2000;72(1–2):273–7.View ArticlePubMedGoogle Scholar
  21. Harbone JB. Phytochemical methods. New York: Chapman & Hall; 1973. p. 1–150.View ArticleGoogle Scholar
  22. Mekonnen A, Mahinda P, Moses NK. Isolation and identification of Staphyloccucu species from Ethiopian cottage Cheese (Ayib) in Debre zeit. Ethiop Vet. Res. 2011;4(1):13–7.Google Scholar
  23. Kuete V, Ngameni B, Simo CCF, Tankeu RK, Ngadjui BT, Meyer JJ, Lall N, Kuiate JR. Antimicrobial activity of the crude extracts and compounds from Ficus chlamydocarpa and Ficus cordata (Moraceae). J Ethnopharmacol. 2008;120:17–24.View ArticlePubMedGoogle Scholar
  24. Aligiannis N, Kalpotzakis E, Mitaku S, Chinou IB. Composition and antimicrobial activity of the essential oil of two Origanum species. J Agric Food Chem. 2001;40:4168–70.View ArticleGoogle Scholar
  25. Oliveira PF, Edeltrudes OL, José PSJ, Evandro LS, Bernadete HCS, Humberto MB. Effectiveness of Lippia sidoides Cham. (Verbenaceae) essential oil in inhibiting the growth of Staphylococcus aureus strains isolated from clinical material. Braz J Pharmacogn. 2006;16(4):510–6.Google Scholar
  26. Rodríguez-Noriega E, Seas C, Guzmán-Blanco M, Mejía C, Alvarez C, Bavestrello L, et al. Evolution of methicillin-resistant Staphylococcus aureus clones in Latin America. Int J Infect Dis. 2010;14:560–6.View ArticleGoogle Scholar
  27. Smith TC, Pearson N. The emergence of Staphylococcus aureus ST398. Vector Borne Zoonotic Dis. 2011;11:327–39.View ArticlePubMedGoogle Scholar
  28. Idu M, Erhabor JO, Towuru GE. Antimicrobial effects of the chloroform and ethanolic leaf extracts of Dacryodes Edulis (G. Don) H.J. Lam, Garcinia Kola Heckel and Chrysophyllum Albidum G. done on some test isolates. Med Sci. 2013;1(3):63–6.Google Scholar
  29. Nwokonkwo DC. The phytochemical study and antibacterial activities of the seed extract of Dacryodes Edulis (African Native Pear). Am J Sci Ind Res. 2014;5(1):7–12.Google Scholar
  30. Mann A. Phytochemical constituents and antimicrobial and grain protectant activities of clove basil (Ocimum gratissimum L.) grown in Nigeria. International. J Plant Res. 2012;2(1):51–8.View ArticleGoogle Scholar
  31. Akinjogunla OJ, Ekoi OH, Odeyemi AT. Phytochemical screening and in vitro antibacterial assessment of aqueous leaf extracts of Vernonia amygdalina (Asteraceae) and Ocimum gratissimum (Lamiaceae) on moxifloxacin resistant Escherichia coli isolated from clinical and environmental samples. Nat Sci. 2011;9(7):42–52.Google Scholar
  32. Latha MKM, Ramkumar L, Pari PNPN, Damodaran V, Rajeshkannan TS. Phytochemical and antimicrobial study of an antidiabetic plant: scoparia dulcis. J Med Food. 2006;9(3):391–4.View ArticlePubMedGoogle Scholar
  33. Akoachere TKJF, Suylika Y, Mbah JA, Ayimele GA, Assob NCJ, Fodouop CPS, et al. In vitro Antimicrobial cctivity of agents from Spilanthes filicaulis and Laportea ovalifolia against some drug resistant bacteria. BJPR. 2015;6(2):76–87.View ArticleGoogle Scholar
  34. Nweze EI, Eze EE. Justification for the use of Ocimum gratissimum L in herbal medicine and its interaction with disc antibiotics. BMC Complement Altern Med. 2009;9:37.PubMed CentralView ArticlePubMedGoogle Scholar
  35. Uma G, Najila BA, Sathica TJ, Josephine BBU. Phytochemical screening and antibacterial activity of Scoparia dulcis extracts. Asian J Pharm Clin Res. 2014;7(3):130–3.Google Scholar
  36. Ndam LM, Mih AM, Fongod AGN, Tening AS, Tonjock RK, Enang JE, et al. Phytochemical screening of the bioactive compounds in twenty (20) Cameroonian medicinal plants. Int J Curr Microbiol App Sci. 2014;3(12):768–78.Google Scholar
  37. Cowan MM. Plant products as antimicrobial agents. Clin Microbiol Rev. 1999;12:564–82.PubMed CentralPubMedGoogle Scholar

Copyright

© Fonkeng et al. 2015

Advertisement