Gram-Negative and Gram-Positive Antibacterial Properties of the Whole Plant Extract of Willow Herb ( Epilobium angustifolium )

Abstract

The emergence of new pathogens and the increase in the number of multidrug-resistant strains in well-established pathogens during the past decade represent a growing public health concern globally. With the current lack of research and development of new antibiotics by large pharmaceutical companies due to poor financial returns, new alternatives need to be explored including natural herbal or plant-based extracts with reported antibacterial properties. Willow herb (Epilobium angustifolium) preparations have been used in traditional aboriginal and folk medicine preparations externally as an antiphlogistic to treat prostate and gastrointestinal disorders and as an antiseptic to treat infected wounds. The authors hypothesized that a whole plant extract of willow herb would exhibit antimicrobial properties on a variety of both Gram-positive and gram-negative bacteria in culture. The authors found that, in comparison to growth controls, willow herb extract significantly inhibited the growth of Micrococcus luteus (p < .01), Staphylococcus aureus (p < .05), Escherichia coli (p < .001), and Pseudomonas aeruginosa (p < .001). They also found that willow herb extract inhibited the growth of bacteria in culture more effectively than vancomycin (p < .05) or tetracycline (p < .004). These results provide preliminary support for the traditional folkloric claim that the plant willow herb possesses antibacterial properties against a variety of gram-positive and gram-negative bacteria. Given that whole plant extract was utilized for this study, further investigations are warranted to determine which specific part of the plant (i.e., leaves, stem, roots, and flowers) possess the antibacterial properties.

Keywords

willow herb antibacterial ethnopharmacology

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References

Amyes

S. G.

(2000). The rise in bacterial resistance is partly because there have been no new classes of antibiotics since the 1960s. British Medical Journal, 320, 199–200.

Annapurna

Chowdary

Lalitha

Ramakrishna

Iyengar

(2004). Antimicrobial activity of Euphorbia nivulia leaf extract. Pharmaceutical Biology, 42, 91–93.

Battinelli

Tita

Evandri

Mazzanti

(2001). Antimicrobial activity of Epilobium. Il Farmaco, 56, 345–348.

Bax

Mullan

Verhoef

(2000). The millennium bugs. The need for and development of new antibacterials. International Journal of Antimicrobial Agents, 16, 51–59.

Boucher

H. W.

Talbot

G. H.

Bradley

J. S.

Edwards

J. E.

Gilbert

Rice

L. B.

… Bartlett

(2009). Bad bugs, no drugs: No ESKAPE! An update from the Infectious Diseases Society of America. Clinical Infectious Diseases, 48, 1–12.

Guven

Celik

Uysal

(2005). Antimicrobial activity of Centaurea species. Pharmaceutical Biology, 43, 67–71.

Kilic

Inandi

(2001). Folkloric treatment of tinea capitis with. Epilobium angustifolium. Plastic and Reconstructive Surgery, 108, 1824–1825.

Larson

(2007). Community factors in the development of antibiotic resistance. Annual Review of Public Health, 28, 435–437.

Maher

McClean

(2006). Investigation of the cytotoxicity of eukaryotic and prokaryotic antimicrobial peptides in intestinal epithelial cells in vitro. Biochemical Pharmacology, 71, 1289–1298.

10.

National Committee for Clinical Laboratory Standards. (1990). Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically—Second edition: Approved standard M7-A2, NCCLS. Villanova, PA: Author.

11.

Nicasio

A. M.

Kuti

J. L.

Nicolau

D. P.

(2008). The current state of multidrug-resistant Gram-negative bacilli in North America. Pharmacotherapy, 28, 235–249.

12.

Norrby

S. R.

Nord

C. E.

Finch

(2005). Lack of development of new antimicrobial drugs: A potential threat to public health. Lancet Infectious Diseases, 5, 115–119.

13.

Overbye

K. M.

Barrett

J. F.

(2005). Antibiotics: Where did we go wrong? Drug Discovery Today, 1, 45–52.

14.

Projan

S. J.

Shales

D. M.

(2004). Antibacterial drug discovery: Is it all downhill from here? Clinical & Microbiology Infections, 10, 18–22.

15.

Rauha

Remes

Heinonen

Hopia

Kahkonen

Kujala

… Vuorela

(2000). Antimicrobial effects of Finnish plant extracts containing flavonoids and other phenolic compounds. International Journal of Food Microbiology, 56, 3–12.

16.

Shebitz

(2003). Plant data sheet. Retrieved March 16, 2006, from http://departments.washington.edu/proppInt/plants/Epilobium.htm

17.

Sheldon

(2005). Antibiotic resistance: A survival strategy. Clinical Laboratory Science, 18, 170–181.

18.

Steekamp

Gouws

M. C.

Gulumian

Elgorashi

E. E.

van Staden

(2006). Studies on antibacterial, anti-inflammatory and antioxidant activity of herbal remedies used in the treatment of benign prostatic hyperplasia and prostatitis. Journal of Ethnopharmacology, 103, 71–75.

19.

Talbot

G. H.

Bradley

Edwards

J. E.

Jr. Gilbert

Scheld

Bartlett

J. G.

(2006). Bad bugs need drugs: An update on the development pipeline from the Antimicrobial Availability Task Force of the Infectious Diseases Society of America. Clinical Infectious Diseases, 42, 657–668.

20.

Tita

Abdel-Haq

Vitalone

Mazzanti

Saso

(2001). Analgesic properties of Epilobium angustifolium, evaluated by the hot plate test and the writhing test. Il Farmaco, 56, 341–343.

21.

Vergidis

P. I.

Falagas

M. E.

(2008). Multidrug-resistant Gram-negative bacterial infections: The emerging threat and potential novel treatment options. Current Opinions in Investigative Drugs, 9, 176–183.

22.

Vitalone

McColl

Thome

Costac

Tita

(2003). Characterization of the effect of Epilobium extracts on human cell proliferation. Pharmacology, 69, 79–87.

23.

Weber

(2006). Update on antimicrobial resistance. Dermatology Nursing, 18, 15–19.

24.

Wenzel

(2004). The antibiotic pipeline—Challenges, costs and values. New England Journal of Medicine, 351, 523–526.

25.

Zinner

S. H.

(2005). The search for new antimicrobials: Why we need new options. Expert Review of Antimicrobial & Infectious Therapies, 3, 907–913.

26.

Zgoda

J. R.

Porter

J. R.

(2001). A convenient microdilution method for screening natural products against bacteria and fungi. Pharmaceutical Biology, 39, 221–230.