1265

Introduction

The incidence of community and hospital infections associated with Staphylococcus aureus has increased. S. aureus is a pathogen with a high virulence, given its capacity of systemic dissemination, where it is frequently related to infections from wounds, pneumonia, septice-mia and endocarditis. Patients, especially those hospital-ized in an intensive care environment, are susceptible to bacteremia, particularly involving methicillin-resistant S. aureus (Selvey et al., 2000; Gibbons, 2004).

Escherichia coli is a Gram-negative bacillus that causes infections, especially neonatal, such as meningitis and sep-ticemia, and even diarrheal diseases, in the whole world, particularly affecting children up to 5 years old. It is found in the vaginal and intestinal flora, thereby being implicated in a variety of infectious diseases. It is believed that vaginal contamination during birth is an important source of neo-natal infection (Krohn et al., 1997; Bingen et al., 1998).

Microbial resistance to drugs employed in the routine treatment of infections has increased morbidity and

RESEARCH ARTICLE

Antibacterial and modulatory effect of Stryphnodendron rotundifolium

Dayanne R. Oliveira1, Francisco E. Brito-Junior1, Elizângela B. Bento1, Edinardo F.F. Matias2, Ana Carla A. Sousa2, Jose G.M. Costa3, Henrique D.M. Coutinho2, Marta R. Kerntopf1, and Irwin R.A. Menezes1

1Laboratory of Pharmacology and Molecular Chemistry, Regional University of Cariri, Crato, Brazil, 2Laboratory of Microbiology and Molecular Biology, Regional University of Cariri, Crato, Brazil, and 3Laboratory of Research in Natural Products, Regional University of Cariri, Crato, Brazil

AbstractContext: Stryphnodendron rotundifolium Mart. (Leguminosae), a tree in Northeast Brazil (Chapada do Araripe), is used in popular medicine to treat different processes such as inflammation and infectious diseases, mainly caused by bacterial pathogens.Objective: This study determined the modulatory and antimicrobial activity of the hydroethanol extract of dried stem bark, the most used form of this natural product, as a remedy by the traditional communities, against standard and clinical isolates of Escherichia coli and Staphylococcus aureus.Material and methods: The antibacterial and modulatory activities of the hydroalcoholic extract from the leaves were obtained by maceration/hydrodistillation method and assayed by microdilution.Results: In the microbiological assays, growth inhibition was demonstrated by this extract against the bacterial strains tested, with minimal inhibitory concentration (MIC) values of 512 µg/mL. However, when a subinhibitory concentration (MIC/8 = 64 µg/mL) was combined with conventional antimicrobial drugs (gentamicin, kanamycin, amikacin and neomycin), the extract showed a potentiating effect, reducing the MIC for all drugs assayed in a range between 312.5 and 2.4 µg/mL.Conclusions: We indicate that the extract of S. rotundifolium showed potential synergistic antibiotic activity. With the results obtained, these extracts proved to be a promising source of antibacterial and modulatory agents.Keywords: Aminoglycosides, antimicrobial activity, multidrug resistant, tannins; flavonoids

Address for Correspondence: H.D.M. Coutinho, Laboratory of Microbiology and Molecular Biology − LMBM, Department of Biological Chemistry, Regional University of Cariri − URCA, Cel. Antonio Luis Street, 1161, Pimenta 63105-000, Crato (CE), Brazil. Tel.: +55 88 31021212. Fax: +55 88 31021291. E-mail: hdmcoutinho@gmail.com

(Received 24 January 2011; revised 21 April 2011; accepted 04 May 2011)

Pharmaceutical Biology, 2011; 49(12): 1265–1270© 2011 Informa Healthcare USA, Inc.ISSN 1388-0209 print/ISSN 1744-5116 onlineDOI: 10.3109/13880209.2011.589857

Pharmaceutical Biology

2011

49

12

1265

1270

24 January 2011

21 April 2011

04 May 2011

1388-0209

1744-5116

© 2011 Informa Healthcare USA, Inc.

10.3109/13880209.2011.589857

NPHB

589857

Phar

mac

eutic

al B

iolo

gy D

ownl

oade

d fr

om in

form

ahea

lthca

re.c

om b

y U

nive

rsity

of

Suss

ex L

ibra

ry o

n 01

/22/

13Fo

r pe

rson

al u

se o

nly.

1266 D.R. Oliveira et al.

Pharmaceutical Biology

mortality, raising hospital costs, which has demonstrated the importance of the discovery of new drugs. Therefore, natural products appear to be an interesting alternative. The use of medicinal plants with antimicrobial potential or that can serve as modifiers of antibiotic activity has stirred the interest of investigators with the aim of discov-ering new drugs for the treatment of multidrug resistant infections (Lu et al., 2007; Ennajar et al., 2009; Coutinho et al., 2010).

The genus Stryphnodendron Mart. (Leguminosae) is composed of about 48 species mentioned in the lit-erature; all are native to the Brazilian Cerrado. Studies of these species have demonstrated that stem bark consists of 20% tannins, which is recommended in popular medi-cine for various afflictions (Cronquist, 1988; Santos & Mello, 2004). Species of this genus are utilized in popular medicine for leukorrhea and gynecologic problems, as an antibacterial, antihemorrhagic, antihypertensive or anti-ulcerogenic, for diarrhea and inflammatory processes, as an astringent, antiseptic or diuretic and for cleansing and healing of wounds, especially in the form of a decoction (Vasconcelos et al., 2004; Souza et al., 2007). The biologi-cal studies of the genus show that Stryphnodendron has several activities: antimicrobial (Sanches et al., 2005), antiulcer (Rodrigues et al., 2008), antiviral (Felipe et al., 2006), trypanocidal (Holetz et al., 2005) and against Candida albicans (Ishida et al., 2006).

Stryphnodendron rotundifolium, popularly known as barbatimão, is a plant species that is endemic to the Cerrado area of Chapada do Araripe, in Northeast Brazil (Correia, 1984). It is utilized for a variety of health prob-lems by local communities, particularly by the inhabit-ants of rural areas. The popular use of this plant, for which there is a lack of scientific investigation, justifies the need for studies to explore the biological potential of the plant.

This work carried out a phytochemical screening of the hydroethanol extract of dried stem bark of S. rotun-difolium to investigate the extract for antibacterial activ-ity and antibiotic-modifying effects, and to correlate the findings with the popular use of this species.

Methods

DrugsGentamicin, amikacin, kanamycin and neomycin were from Sigma Co. (St. Louis, MO). The solutions of the anti-biotics were prepared based on the recommendations of the Clinical and Laboratory Standards Institute (NCCLS, 2008).

Bacterial strainsThe following bacterial strains were used: E. coli (EC27) and S. aureus (SA358) with a drug resistance profile described in Table 1. All strains were maintained on heart infusion agar slants (Difco Laboratories Ltd). Before assays, bacterial cells were grown overnight at 37°C in brain heart infusion broth (BHI; Difco Laboratories Ltd).

Plant materialThe stem bark of the plant species S. rotundifolium was collected in March 2010 (rainy season) from the municipality of Crato, Ceara, Brazil, using a GPS device. The following coordinates were obtained: 7° 22′ 2.8″ S; 39° 28′ 42.4″ W; the altitude was 892 m above sea level. The botanic material was identified by Dr. Maria Arlene Pessoa da Silva and a dried specimen of the species deposited as #4661 in the Herbario Caririense Dardano de Andrade—Lima of the Universidade Regional do Cariri—URCA.

Preparation of hydroalcoholic extract of the bark of S. rotundifoliumThe plant material (dried stem bark—3710.5 g) was extracted in the cold water in a thermal bath, using 99.9% ethanol in a 1:1 proportion (8.7 L of solvent) for 72 h. The extracts were filtered and vacuum-concentrated using a rotary evaporator, yielding a crude lyophilizate of the extracts, as shown in Table 2. For the tests, the extracts were diluted in dimethyl sulfoxide at a concentration of 10 mg/mL, followed by dilution in distilled water to give a concentration of 1024 µg/mL.

Phytochemical prospectingPhytochemical prospecting for the detection of tannins, flavonoids, saponins, steroids, triterpenes, cumarins, quinones, organic acids and alkaloids was carried out according the method described by Matos (1997). The results are given in Table 3.

Antimicrobial activity testThe minimal inhibitory concentration (MIC) of each extract was determined in a microdilution assay (NCCLS, 2008), utilizing an inoculum of 100 µL of each bacterial strain, suspensions in BHI broth up to a final concentration of 105 colony-forming units/mL in 96-well microdilution plates with serial twofold dilutions. A volume of 100 µL of each extract solution was added to each well. The final concentrations of the extracts varied from 512 to 8 µg/mL. MIC was determined as the least concentration that inhib-ited bacterial growth. The potentiating effect of the extracts

Table 1. Bacterial source and antibiotic resistance profile.Bacteria Source Antibiotic resistanceEscherichia coli 27 Surgical wound Ast, Ax, Amp, Ami, Amox, Ca, Cfc, Cf, Caz, Cip, Clo, Im, Can, Szt, Tet, TobStaphylococcus aureus 358 Surgical wound Oxa, Gen, Tob, Ami, Can, Neo, Para, But, Sis, NetAst, aztreonam; Ax, amoxacilin; Amp, ampicillin; Ami, amikacin; Amox, amoxicillin; Ca, cefadroxil; Cfc, cefaclor; Cf, cefalotin; Caz, ceftazidime; Cip, ciprofloxacin; Chlo, chloranphenicol; Im, imipenem; Kan, kanamycin; Szt, sulfametim; Tet, tetracycline; Tob, tobramycin; Oxa, oxacillin; Gen, gentamicin; Neo, neomycin; Para, paramomycin; But, butirosin; Sis, sisomicin; Net, netilmicin.

Phar

mac

eutic

al B

iolo

gy D

ownl

oade

d fr

om in

form

ahea

lthca

re.c

om b

y U

nive

rsity

of

Suss

ex L

ibra

ry o

n 01

/22/

13Fo

r pe

rson

al u

se o

nly.

Activity of Stryphnodendron rotundifolium 1267

© 2011 Informa Healthcare USA, Inc.

was tested against strains of E. coli (EC27) and S. aureus (SA358) in combination with the following antimicrobial agents: gentamicin, kanamycin, neomycin and amikacin at final concentrations varying from 1024 to 1 µg/mL after serial two-fold dilutions as cited before. The plates were incubated under aerobic conditions for 24 h at 37°C.

Results

A preliminary ethnopharmacologic study revealed that S. rotundifolium is used as a popular medicine by tradi-tional communities, where the stem bark of this species represents the part of the plant recommended for use, especially in the form of a decoction. This medicinal plant is used in treating a variety of ailments, including wounds and infections, gastric disturbances, inflam-mation, painful conditions, dermatoses, pulmonary disease, diseases of the female reproductive tract and diseases of the prostate (data not shown). Phytochemical prospecting of hydroalcoholic extract of S. rotundifolium (HESR) allowed the identification of tannins, pyrogallics, flavones, flavonoids, flavononols, xanthones, chalcons, flavonones and steroids (Table 3).

HESR demonstrated antimicrobial activity of little sig-

nificance against the bacterial strains tested, with MIC

values of 512 µg/mL. When HESR at a concentration

of 64 µL/mL was combined with the aminoglycosides

(Table 4), it demonstrated a substantial potentiating

effect in relation to the antibacterial action of the drugs

alone, reducing the concentration necessary to inhibit

the bacterial growth.

Discussion

The rise in the occurrence of multidrug resistant infec-tions has stimulated research into the evaluation of natural products for antimicrobial activity (Arango et al., 2004). Various biological properties are attributed to the genus Stryphnodendron sp., and in vitro assays with extracts of species of this genus have shown antibacterial activity (Audi et al., 2004; Holetz et al., 2005).

Phenolic compounds, including tannins and fla-vonoids, have demonstrated their therapeutic poten-tial as anti-inflammatory, antifungal, antimicrobial, antioxidant and wound-healing agents (Santos et al., 2004). Data from the literature confirm the use of stem bark of species of the genus Stryphnodendron for vari-ous ailments. Investigations to determine the effect of bark extracts of species of this genus have demon-strated the presence of tannins and flavonoids, their use as antimicrobial agents (Matos, 1997; Singh et al., 2006; Lopes et al., 2003). Fractions of the extracts were also used for the identification of antibacterial proper-ties against S. aureus and Gram-negative bacteria, also demonstrating a growth-inhibitory effect and antiradi-cal properties. This species contains 12–19% tannins in the bark of stems (Lopes et al., 2003). The precise profile of active constituents of S. rotundifolium is still not well known; however, tannins can be considered the most relevant substances due to its high content. The chemi-cal compositions of the Stryphnodendron genus indicate the presence of sapogenines and proanthocyanidins (Tursch et al., 1963), gallocatechin (Reicher et al., 1992) and monomeric, dimeric or trimeric condensed tannins (Lopes et al., 2009). Three species of Stryphnodendron genus [S. adstringens (Mart.) Coville, S. polyphyllum and S. obovatum Benth.] demonstrated that the main compounds in ethanol extract are gallic acid and gallo-catechin. The study performed by Mello et al. (1996a,b) showed that the concentration of gallic acid is variable. However, the concentration of gallocatechin is similar between the three species.

Table 2. Dry mass and yield of hydroalcoholic extracts (g).Species Solvent used Leaves YieldStryphnodendron rotundifolium Mart.

HESR 3710.5 627.8

HESR, hydroalcoholic extract of Stryphnodendron rotundifolium Mart.

Table 3. Phytochemical prospection of hydroalcoholic extract of Stryphnodendron rotundifolium Mart.Metabolites

Extracts 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17HESR − + − − − + + + + + + − − + − − +1, phenols; 2, tannin pyrogallates; 3, tannin phlobaphenes; 4, anthocyanins; 5, anthocyanidins; 6, flavones; 7, flavonols; 8, xanthones; 9, chalcones; 10, aurones; 11, flavononols; 12, leucoanthocyanidins; 13, catechins; 14, flavonones; 15, alkaloids; 16, terpenes; 17, steroids; (+), presence; (−), absence.

Table 4. MIC values (μg/mL) of aminoglycosides in the absence and presence of 64 µg/mL of HESR against Escherichia coli 27 and Staphylococcus aureus 358.

EC27 SA358 Drugs and extract alone Drugs + HESR Drugs and extract alone Drugs + HESRGentamicin 2500 19.5 39 2.4Kanamycin 2500 62.5 2500 312.5Amikacin 156.2 9.7 78.1 9.7Neomycin 312.5 39 312.5 9.7HESR 512 — 512 —

Phar

mac

eutic

al B

iolo

gy D

ownl

oade

d fr

om in

form

ahea

lthca

re.c

om b

y U

nive

rsity

of

Suss

ex L

ibra

ry o

n 01

/22/

13Fo

r pe

rson

al u

se o

nly.

1268 D.R. Oliveira et al.

Pharmaceutical Biology

Susceptibility tests using the diffusion method showed that Stryphnodendron adstringens was active against Streptococcus mutans, S. aureus, Actinobacillus actinomycetemcomitans and C. albicans, but that only the ethanol extract also had antifungal activity (Santos et al., 2002). However, it is important to mention that the microdilution method, employed in the present investi-gation, currently represents the technique most accepted for this bioassay (Hadacek & Greger, 2000).

Other studies with fractions of extracts of the stem bark of S. adstringens, using the microdilution tech-nique, revealed antifungal activity against Candida spp., attributed to level of tannins present in this species (Ishida et al., 2006). In this context, the evaluation of the antioxidant and antimicrobial activities of the bark of S. adstringens, by the dilution assay, can verify the presence of antioxidant and antimicrobial properties, where both bioactive actions are associated with the presence of total phenolic compounds, such as tannins and flavonoids (Souza et al., 2007).

Assays carried out with extracts of plants rich in tan-nins have demonstrated bactericidal and fungicidal effects (Scalbert, 1991), antiviral activity (De Bruyne et al., 1999), inhibition of enzymes such as glycosyltransferases of S. mutans and Streptococcus sobrinus (Ooshima et al., 1993) and antioxidant activity (Moure et al., 2001). The capacity of tannins to form complexes with proteins is accepted as the basis for protection against insects, fungi and bacteria, as well as their pharmacological proper-ties. The exact mechanisms by which these compounds exert their antimicrobial effects have not been well elu-cidated. However, three hypotheses have been proposed. One would be the inhibition of enzymes of bacteria and fungi and/or complexation of their substrates; another mechanism would be represented by their action on the cell membranes of microorganisms, thereby altering metabolism; and the third would be complexation with metal ions (Mila et al., 1996), reducing the availability of these elements in metabolism (Ho et al., 2001; Schofield et al., 2001; Santos & Mello, 2004).

There was a significant difference between gallocat-echin and epigallocatechin, which may be related to the stereochemistry of the compounds. Note the presence of a methoxyl group at position 4′ of gallocatechin, which reduced its free-radical scavenging activity compared to the non-substituted compound. There was a significant difference between dimers with a hydroxyl group at posi-tion 5 (prodelphinidins) and those without a hydroxyl group at this position (prorobinetinidins). This confirms the observation of van Acker et al. (1996) that compounds with groups of the pyrogallol type (trihydroxylated) pos-sess greater activity than compounds with groups of the catechol type (dihydroxylated). However, this is the first report to compare antioxidant activity between proanthocyanidins with or without a hydroxyl group at a ring position 5. For this evaluation, there are no cur-rently available parameters for comparison because 5-deoxyproanthocyanidins have been isolated from only

a few plant species, including Stryphnodendron spp. (van Acker et al., 1996).

Salazar-Aranda et al. (2009) showed that extract from Ceanothus coeruleus displayed the greatest activ-ity against yeast as well as the best antioxidant activity. Seven (46.6%) of the 15 extracts that showed antioxidant activity displayed antibacterial activity as well, and nine (80%) resulted active against yeast. The study of Belofsky et al. (2004) demonstrated an increase in the antimicro-bial activity of pure compounds when they are combined with antioxidants. Therefore, we consider that if both antimicrobial and antioxidant compounds exist in the extracts, they could interact and enhance the antimicro-bial activity.

A variety of studies have demonstrated the antimi-crobial and antifungal properties of flavonoids (Rauha et al., 2000; Sohn et al., 2004). These compounds have the capacity to form complexes with extracellular soluble proteins which bind to the bacterial cell wall (Tsuchiya et al., 1996). Studies have shown that many natural com-pounds alter the permeability of the cell membrane, favoring the penetration of antibiotics (Burt, 2004). The interaction with bacterial enzymes can also be related to the synergistic mechanism of natural products with antibiotics (Wendakoon & Sakaguchi, 1995), which can be obtained from an extract or from the combination of extracts, synthetic products, antibiotics and other natural products (Hemaiswarya et al., 2008; Wagner & Ulrich-Merzenich, 2009).

There are many reports that condensed tannins and gallic acid are responsible for different antimicrobial activities (Ishida et al., 2006). Santos et al. (2002) reported that the degree of polymerization is an important factor in biological activity. This has been discussed by Field and Lettinga (1992) who demonstrated that an increase in the degree of polymerization progressively increases the degree of reaction to tannins. Previous studies showed that the number of hydroxyl groups in the B-ring affects the level of growth inhibition of several microorgan-isms, suggesting that proanthocyanidin trihydroxylated B-rings may have better antimicrobial action. The high degree of polymerization and hydroxylation of the con-densed tannins appears to be an important factor in its antifungal activity. Scalbert proposed different mecha-nisms to explain tannin antimicrobial activity. These include (i) inhibition of extracellular microbial enzymes by complexating with substrates of bacteria and fungi; (ii) a mechanism involving the complexation of tannins with metabolic ions required for microbial growth, and (iii) direct action of tannins on microbial metabolism through inhibition of oxidative phosphorylation (Scalbert, 1991). In addition, tannins are able to complex with other mol-ecules including macromolecules such as proteins and polysaccharides (Haslam, 1996).

For the species S. rotundifolium, the investigation of the modulatory activity of bark extracts represents a pio-neering and promising study for the development of new antimicrobial drugs. However, studies on the synergism

Phar

mac

eutic

al B

iolo

gy D

ownl

oade

d fr

om in

form

ahea

lthca

re.c

om b

y U

nive

rsity

of

Suss

ex L

ibra

ry o

n 01

/22/

13Fo

r pe

rson

al u

se o

nly.

Activity of Stryphnodendron rotundifolium 1269

© 2011 Informa Healthcare USA, Inc.

between natural products and antibacterial drugs have been conducted with other plant species, for example, Momordica charantia L. (Cucurbitaceae), Turnera ulmifolia L. (Turneraceae), Hyptis martuisii Benth. and Mentha arvenis L. (Lamiaceae) (Coutinho et al., 2009a–c, 2010).

Conclusions

The screening of active molecules in the “barbatimão” extract is an important research activity that should be considered in future studies. It is very likely that tannin is the main antimicrobial constituent in the plant extract; however, the exact mechanism and the compound responsible for the antimicrobial activities are currently unclear. Further studies need to clarify if there is a syner-gistic effect of molecules responsible for the antimicro-bial activity.

Acknowledgements

We are thankful to Fundação Cearense de Amparo à Pesquisa (FUNCAP-Brazil/processes 1081/06 and 0191-2.10/08 and BPI grants) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq-Brazil) for providing support to this research and to Faculty of Medicine of Juazeiro do Norte and Faculty of Leão Sampaio for providing animals to this research.

Declaration of interest

The authors report no declarations of interest.

ReferencesArango ACM, Sánchez JGB, Galvis LAB. (2004). Productos naturales

con actividad antimicótica. Rev Esp Quim, 17, 325–331.Audi EA, De Toledo CEM, Dos Santos FS, Bellanda PR, Alves-do-Prado

W, Ueda-Nakamura T, Nakamura CV, Sacuragui CM, Bersani-Amado CA, Palazzo de Mello JC. (2004). Biological activity and quality control of extract and stem bark from Stryphnodendron adstringens. Lat Am J Pharm, 23, 328–333.

Belofsky G, Percivill D, Lewis K, Tegos GP, Ekart J. (2004). Phenolic metabolites of Dalea versicolor that enhance antibiotic activity against model pathogenic bacteria. J Nat Prod, 67, 481–484.

Bingen E, Picard B, Brahimi N, Mathy S, Desjardins P, Elion J, Denamur E. (1998). Phylogenetic analysis of Escherichia coli strains causing neonatal meningitis suggests horizontal gene transfer from a predominant pool of highly virulent B2 group strains. J Infect Dis, 177, 642–650.

Burt S. (2004). Essential oils: Their antibacterial properties and potential applications in foods—a review. Int J Food Microbiol, 94, 223–253.

Correia P. (1984). Dicionário das plantas úteis do Brasil e exóticas cultivadas. Vol III. Rio de Janeiro: Imprensa Nacional, Ministério da Agricultura, 499–501.

Coutinho HDM, Costa JGM, Lima EO, Falcão-Silva VS, Siqueira Jr JP. (2009a). Herbal therapy associated with antibiotic therapy: Potentiation of the antibiotic activity against methicillin—resistant Staphylococcus aureus by Turnera ulmifolia L. BMC Complement Altern Med, 9, 13.

Coutinho HD, Costa JG, Lima EO, Falcão-Silva VS, Siqueira-Júnior JP. (2009b). In vitro interference of Hyptis martiusii Benth. &

chlorpromazine against an aminoglycoside-resistant Escherichia coli. Indian J Med Res, 129, 566–568.

Coutinho HDM, Costa JGM, Lima EO, Falcão-Silva VS, Siqueira Jr JP. (2009c). Potentiating effect of Mentha arvensis and chlorpromazine in the resistance to aminoglycosides of methicillin-resistant Staphylococcus aureus. In Vivo, 23, 287–290.

Coutinho HD, Costa JG, Falcão-Silva VS, Siqueira-Júnior JP, Lima EO. (2010). Effect of Momordica charantia L. in the resistance to aminoglycosides in methicilin-resistant Staphylococcus aureus. Comp Immunol Microbiol Infect Dis, 33, 467–471.

Cronquist A. (1988). The Evolution and Classification of Flowering Plants. New York: The New York Botanical Garden, 261–449.

De Bruyne T, Pieters L, Witvrouw M, De Clercq E, Vanden Berghe D, Vlietinck AJ. (1999). Biological evaluation of proanthocyanidin dimers and related polyphenols. J Nat Prod, 62, 954–958.

Ennajar M, Bouajila J, Lebrihi A, Mathieu F, Abderraba M, Raies A, Romdhane M. (2009). Chemical composition and antimicrobial and antioxidant activities of essential oils and various extracts of Juniperus phoenicea L. (Cupressacees). J Food Sci, 74, M364–M371.

Felipe AM, Rincão VP, Benati FJ, Linhares RE, Galina KJ, de Toledo CE, Lopes GC, de Mello JC, Nozawa C. (2006). Antiviral effect of Guazuma ulmifolia and Stryphnodendron adstringens on poliovirus and bovine herpesvirus. Biol Pharm Bull, 29, 1092–1095.

Field JA, Lettinga G. (1992). Toxicity of tannic compounds to microorganisms. In: Hemingway RW, Laks PE, eds. Plant Polyphenols. New York: Plenum Press, 673–689.

Gibbons S. (2004). Anti-staphylococcal plant natural products. Nat Prod Rep, 21, 263–277.

Hadacek F, Greger H. (2000). Testing of antifungal natural products: Methodologies, comparability of results and assay choice. Phytochem Anal, 11, 137–147.

Haslam E. (1996). Natural polyphenols (vegetable tannins) as drugs: Possible modes of action. J Nat Prod, 59, 205–215.

Hemaiswarya S, Kruthiventi AK, Doble M. (2008). Synergism between natural products and antibiotics against infectious diseases. Phytomedicine, 15, 639–652.

Ho KY, Tsai CC, Huang JS, Chen CP, Lin TC, Lin CC. (2001). Antimicrobial activity of tannin components from Vaccinium vitis-idaea L. J Pharm Pharmacol, 53, 187–191.

Holetz FB, Ueda-Nakamura T, Dias Filho BP, Mello JC, Morgado-Díaz JA, Toledo CE, Nakamura CV. (2005). Biological effects of extracts obtained from Stryphnodendron adstringens on Herpetomonas samuelpessoai. Mem Inst Oswaldo Cruz, 100, 397–401.

Ishida K, de Mello JC, Cortez DA, Filho BP, Ueda-Nakamura T, Nakamura CV. (2006). Influence of tannins from Stryphnodendron adstringens on growth and virulence factors of Candida albicans. J Antimicrob Chemother, 58, 942–949.

Krohn MA, Thwin SS, Rabe LK, Brown Z, Hillier SL. (1997). Vaginal colonization by Escherichia coli as a risk factor for very low birth weight delivery and other perinatal complications. J Infect Dis, 175, 606–610.

Lopes GC, Nakamura CV, Dias-Filho BP, Mello JCP. (2003). Estudos físico-químico, químico e biológico de cascas e extratos de Stryphnodendron polyphyllum Mart. (Leguminosae). Braz J Pharmacogn, 13, 24–27.

Lopes GC, Sanches ACC, Toledo CEM, Isler AC, Mello JCP. (2009). Determinação quantitativa de taninos em três espécies de Stryphnodendron por cromatografia líquida de alta eficiência. Braz J Pharm Sci, 45, 135–143.

Lu Y, Zhao YP, Wang ZC, Chen SY, Fu CX. (2007). Composition and antimicrobial activity of the essential oil of Actinidia macrosperma from China. Nat Prod Res, 21, 227–233.

Matos FJA. (1997). Introdução à Fitoquímica Experimental. Fortaleza: Edições UFC.

Mello JCP, Petereit F, Nahrstedt A. (1996a). Flavan-3-ols and prodelphinidins from Stryphnodendorn adstringens. Phytochemistry, 41, 807–813.

Mello JCP, Petereit F, Nahrstedt A. (1996b). Prorobinetinidins from Stryphnodendorn adstringens. Phytochemistry, 42, 857–862.

Phar

mac

eutic

al B

iolo

gy D

ownl

oade

d fr

om in

form

ahea

lthca

re.c

om b

y U

nive

rsity

of

Suss

ex L

ibra

ry o

n 01

/22/

13Fo

r pe

rson

al u

se o

nly.

1270 D.R. Oliveira et al.

Pharmaceutical Biology

Mila I, Scalbert A, Expert D. (1996). Iron withholding by plant polyphenols and resistance to pathogens and rots. Phytochemistry, 42, 1551–1555.

Moure A, Cruz JM, Fraonco D, Dominguez JM, Sinero J, Dominguez H, Nunez MJ, Parajó JC. (2001). Natural antioxidants from residual sources. Food Chem, 72, 145–171.

NCCLS. (2008). Performance standards of antimicrobial disk susceptibility test. Ninth Informational Supplement. NCCLS Document M100-S9. Wayne, PA: National Committee for Clinical Laboratory Standards, 120–126.

Ooshima T, Minami T, Aono W, Izumitani A, Sobue S, Fujiwara T, Kawabata S, Hamada S. (1993). Oolong tea polyphenols inhibit experimental dental caries in SPF rats infected with mutans streptococci. Caries Res, 27, 124–129.

Rauha JP, Remes S, Heinonen M, Hopia A, Kähkönen M, Kujala T, Pihlaja K, Vuorela H, Vuorela P. (2000). Antimicrobial effects of Finnish plant extracts containing flavonoids and other phenolic compounds. Int J Food Microbiol, 56, 3–12.

Reicher F, Leitner SC, Sierakowski MR, Fontana JD, Correa JB. (1992). Properties of the seed gum of Strypnodendron barbatiman (barbatimao). Appl Biochem Biotechnol, 34-35, 349–357.

Rodrigues FFG, Cardoso ALH, Campos AR, Costa JGM. (2008). Antiulcer and antimicrobial activities of Stryphnodendron rotundifolium Mart. Pharmacogn Mag, 4, 193–196.

Salazar-Aranda R, Pérez-López LA, López-Arroyo J, Alanís-Garza BA, Waksman de Torres N. (2009). Antimicrobial and antioxidant activities of plants from northeast of Mexico. Evid Based Complement Alternat Med (in press).

Santos SC, Costa WF, Ribeiro JP, Guimarães DO, Ferri PH, Ferreira HD, Seraphin JC (2002): Tannin composition of barbatimão species. Fitoterapia 73: 292–299

Santos SC, Mello JCP. (2004). Taninos. In: Simões CMO, Schenkel EP, Gosmann G, Mello JCP, Mentz LA, Petrovick PR, eds. Farmacognosia: Da Planta ao Medicamento. Porto Alegre: Editora da UFRGS/Editora da UFSC 527–554.

Scalbert A. (1991). Antimicrobial properties of tannins. Phytochemistry, 30, 3875–3883.

Schofield PD, Mbugua M, Pell AN. (2001). Analysis of condensed tannins: A review. Animal Feed Sci Technol, 91, 21–40.

Selvey LA, Whitby M, Johnson B. (2000). Nosocomial methicillin-resistant Staphylococcus aureus bacteremia: Is it any worse

than nosocomial methicillin-sensitive Staphylococcus aureus bacteremia? Infect Control Hosp Epidemiol, 21, 645–648.

Singh G, Maurya S, Lampasona MP, Catalan C. (2006). Chemical constituents, antifungal and antioxidative potential of Foeniculum vulgare oil and its acetone extract. Food Control, 17, 745–752.

Sohn HY, Son KH, Kwon CS, Kwon GS, Kang SS. (2004). Antimicrobial and cytotoxic activity of 18 prenylated flavonoids isolated from medicinal plants: Morus alba L., Morus mongolica Schneider, Broussonetia papyrifera (L.) Vent, Sophora flavescens Ait and Echinosophora koreensis Nakai. Phytomedicine, 11, 666–672.

Souza TM, Severi JA, Silva VYA, Santos E, Pietro RCLR. (2007). Bioprospecção de atividade antioxidante e antomicrobiana da casca de Stryphnodendron adstringens (Mart.) Coville (Leguminosae mimosoideae). Rev Ciênc Farm Básica Apl, 28, 221–226.

Tsuchiya H, Sato M, Miyazaki T, Fujiwara S, Tanigaki S, Ohyama M, Tanaka T, Iinuma M. (1996). Comparative study on the antibacterial activity of phytochemical flavanones against methicillin-resistant Staphylococcus aureus. j Ethnopharmacol, 50, 27–34.

Tursch B, Tursch E, Harrison IT, Brazão Da Silva GBCTC, Monteiro HJ, Gilbert B, Mors WB, Djerassi C. (1963). Terpenoids. LIII. Demonstration of ring conformational changes in triterpenes of the β-amyrin class isolated from Stryphnodendron coriaceum. J Org Chem, 28, 2390–2394.

van Acker SA, van den Berg DJ, Tromp MN, Griffioen DH, van Bennekom WP, van der Vijgh WJ, Bast A. (1996). Structural aspects of antioxidant activity of flavonoids. Free Radic Biol Med, 20, 331–342.

Vasconcelos MCA, Rodovalho NCM, Pott A, Pott VJ, Ferreira AMT, Arruda ALA, Marques MCS, Castilho RO, Bueno NR. (2004). Evaluation of biological activities of the seeds of Stryphnodendron obovatum Benth. (Leguminosae). Braz J Pharmacogn, 14, 121–127.

Wagner H, Ulrich-Merzenich G. (2009). Synergy research: Approaching a new generation of phytopharmaceuticals. Phytomedicine, 16, 97–110.

Wendakoon C, Sakaguchi M. (1995). Inhibition of amino acid decarboxylase activity of Enterobacter aerogenes by active components in spices. J Food Protect, 58, 280–283.

Phar

mac

eutic

al B

iolo

gy D

ownl

oade

d fr

om in

form

ahea

lthca

re.c

om b

y U

nive

rsity

of

Suss

ex L

ibra

ry o

n 01

/22/

13Fo

r pe

rson

al u

se o

nly.