2.2.2. Plant pathogens

Plant extracts have also been tested on bacteria and fungi that affect fruits and vegetables, causing rot diseases during postharvest handling, to find an alternative to chemical pesticides, which are harmful to the environment and human health. An aqueous T. officinale root extract (S) at different dilutions (S, S/2 to S/100) caused significant inhibition to mycelial growth in A. alternata (70% for S to 17% for S/100), P. expansum (67% for S to 5.3% for S/100), and M. piriformis (70% for S to 16% for S/100) [46]. In the case of R. solani and C. sativus, a Taraxacum acetyl acetate extract at a concentration of 100 mg/mL exhibited a weak effect on the growth of these plant pathogens and no inhibition of F. oxysporum [22]. A methanolic extract of Taraxacum at 0.2 mg/mL was not effective against A. niger, A. flavus, A. fumigates, or R. solani [37]. A methanolic extract of Taraxacum sp. displayed weak activity against C. sativus, F. oxysporum, and R. solani at 5 mg/disc and a water extract displayed no activity at all [56].

retarded bacterial growth during refrigerated storage, prolonging shrimp shelf life for up to

*Taraxacum* Genus: Potential Antibacterial and Antifungal Activity

http://dx.doi.org/10.5772/intechopen.71619

259

In the case of the meat industry, an herb mixture including T. officinale as a substitute for fodder antibiotics in pig feeding revealed positive growth of the animal and no change in meat quality, confirming the possibility of using herbs as an antibiotic substitute in pig feed [77, 78]. Aqueous and ethanolic extracts of T. mongolicum could also inhibit four pathogenic bacteria responsible for cow mastitis, a serious disease in the cow industry, at concentrations of 0.13, 0.25, and 0.5 g/mL. In this case, the ethanolic extracts displayed slightly better antibacterial activities than aqueous extracts. For E. coli, S. aureus, S. agalactiae, and S. dysgalactiae, inhibition zone diameters were slightly larger for aqueous than for ethanolic extracts but showed between medium and high sensitivity [79]. Dandelion extract can not only be used to control pathogens but also to supplement the diet of animals, which could result in increased meat, milk, whey, and other yields, contributing to the food industry. Alternatively, the extracts could be utilized in the agricultural industry as biofertilizers to promote plant growth and

Innate plant immunity involves various defense responses, including cell wall reinforcements, lytic enzyme biosynthesis, secondary metabolite production, and pathogenesis-related proteins. To protect themselves from non-beneficial microorganisms, plants accumulate secondary metabolites that form chemical barriers to microbial attacks (phytoanticipins) and produce antimicrobials (phytoalexins) [80]. Phenolics and terpenoids are considered the primary mechanisms for plant defenses because these reduce microbial attacks by disrupting the cell membranes in microorganisms, bind to adhesins and cell wall compounds, and inactivate enzymes, among other roles [81]. The action mechanisms of natural compounds are related to the disintegration of the cytoplasmic membrane and destabilization of the proton motive force, electron flow, active transport, coagulation of the cell content, inhibition of protein synthesis, inhibition of DNA synthesis, and the synthesis of metabolites used for DNA synthesis [82]. Some action mechanisms are specific to certain targets and some targets may also be affected by more than one mechanism [83]. A general scheme of the action's sites and antimicrobial

Even though Taraxacum is a plant with extremely high pathogen resistance, the underlying molecular mechanisms of antimicrobial activity are poorly studied [68]. Until now, most of the research on Taraxacum has focused on elucidating the compounds present in the extract, and, to a lesser extent, on the mechanism involved in the antimicrobial activity itself. One study specifically illustrated the effect of four proteins from T. officinale flowers on fungi by light microscopy and distinguished two modes of antimicrobial action, depending on the fungus tested. Taraxacum proteins completely blocked conidia germination or induced thickening of multiple local hyphae and irreversible cytoplasm plasmolysis [68, 69]. Different extracts from this genus showed positive inhibitory activity in controlled studies and were characterized by protein synthesis inhibition (e.g. chloramphenicol, tetracycline, gentamicin, and kanamycin) and cell wall synthesis (e.g. amphotericin, cefixime, cephalothin, and penicillin). These

potential mechanism is presented in Figure 1 of Supporting Information.

strengthen the plant against biotic and abiotic stress.

2.3. Taraxacum antimicrobial action mechanisms

10 days [76].

A T. officinale hydro-methanolic extract tested the inhibition of conidial germination and inhibition of germ tube elongation for several plant pathogens at several dilutions (0.25, 0.5, and 0.75) using a microassay method on slides. Dilution at 0.75 showed inhibition of conidial germination values of 2, 3, 4, 9, 11, and 12% for P. italicum, A. niger, A. carbonarius, B. cinerea, M. laxa, and P. digitatum, respectively. For these same strains, excluding A. carbonarius, inhibition of germ tube elongation values were 56, 45, 38, 5 and 42%, respectively. For P. expansum, the plant extract did not show positive results for inhibition of conidial germination or inhibition of germ tube elongation. In artificially inoculated fruits, the extract applied to nectarines was not protective against brown rot development from M. laxa, while for apricots effects were similar to those of the negative control for P. digitatum [35]. Dichloromethane and diethyl ether T. officinale extracts were tested on P. expansum by applying either a solution or its vapor to paper discs. The dichloromethane extract was more active of the two models, though direct inoculation in apples offered no observable inhibition [26]. Water extracts of T. officinale and T. platycarpum were tested against C. lagenarium in cucumber, exhibiting inhibition rates of the anthracnose lesions of 1.9 and 13% in treated leaves, and 11 and 5.3% in untreated leaves, respectively. These results were not significant compared to other plant extracts [42]. In vivo evaluation of protective effects in plant tissue has not been as successful as the in vitro assays, which is typical in cases of inhibitory activity validation. To avoid these ineffective results, concentrations are increased to demonstrate the pathogen control effect.

#### 2.2.3. Animal pathogens

Regarding animal pathogens, Saprolegnia infections can account for significant salmonid losses. Treatment is difficult and there are reservations regarding efficacy, prompting a search for suitable alternatives. A T. officinale root extract was not as effective as a fungistatic at 10, 100, 1000, or 10,000 mg/mL [61]. The effects of Taraxacum polysaccharides were studied on the preservation of white shrimp (Penaeus vannamei) during refrigerated storage (10 days at 4C) by soaking the shrimps in aqueous extracts (1–3% w/v). Samples were periodically evaluated for total viable count, pH value, and total volatile basic nitrogen, which resulted in 2–3% of shrimp in fresh conditions (<30 mg/100 mg of total volatile basic nitrogen) and a total viable count that only increased slightly during storage. This indicated that the treatment effectively retarded bacterial growth during refrigerated storage, prolonging shrimp shelf life for up to 10 days [76].

In the case of the meat industry, an herb mixture including T. officinale as a substitute for fodder antibiotics in pig feeding revealed positive growth of the animal and no change in meat quality, confirming the possibility of using herbs as an antibiotic substitute in pig feed [77, 78]. Aqueous and ethanolic extracts of T. mongolicum could also inhibit four pathogenic bacteria responsible for cow mastitis, a serious disease in the cow industry, at concentrations of 0.13, 0.25, and 0.5 g/mL. In this case, the ethanolic extracts displayed slightly better antibacterial activities than aqueous extracts. For E. coli, S. aureus, S. agalactiae, and S. dysgalactiae, inhibition zone diameters were slightly larger for aqueous than for ethanolic extracts but showed between medium and high sensitivity [79]. Dandelion extract can not only be used to control pathogens but also to supplement the diet of animals, which could result in increased meat, milk, whey, and other yields, contributing to the food industry. Alternatively, the extracts could be utilized in the agricultural industry as biofertilizers to promote plant growth and strengthen the plant against biotic and abiotic stress.

#### 2.3. Taraxacum antimicrobial action mechanisms

2.2.2. Plant pathogens

258 Herbal Medicine

2.2.3. Animal pathogens

Plant extracts have also been tested on bacteria and fungi that affect fruits and vegetables, causing rot diseases during postharvest handling, to find an alternative to chemical pesticides, which are harmful to the environment and human health. An aqueous T. officinale root extract (S) at different dilutions (S, S/2 to S/100) caused significant inhibition to mycelial growth in A. alternata (70% for S to 17% for S/100), P. expansum (67% for S to 5.3% for S/100), and M. piriformis (70% for S to 16% for S/100) [46]. In the case of R. solani and C. sativus, a Taraxacum acetyl acetate extract at a concentration of 100 mg/mL exhibited a weak effect on the growth of these plant pathogens and no inhibition of F. oxysporum [22]. A methanolic extract of Taraxacum at 0.2 mg/mL was not effective against A. niger, A. flavus, A. fumigates, or R. solani [37]. A methanolic extract of Taraxacum sp. displayed weak activity against C. sativus, F. oxysporum,

A T. officinale hydro-methanolic extract tested the inhibition of conidial germination and inhibition of germ tube elongation for several plant pathogens at several dilutions (0.25, 0.5, and 0.75) using a microassay method on slides. Dilution at 0.75 showed inhibition of conidial germination values of 2, 3, 4, 9, 11, and 12% for P. italicum, A. niger, A. carbonarius, B. cinerea, M. laxa, and P. digitatum, respectively. For these same strains, excluding A. carbonarius, inhibition of germ tube elongation values were 56, 45, 38, 5 and 42%, respectively. For P. expansum, the plant extract did not show positive results for inhibition of conidial germination or inhibition of germ tube elongation. In artificially inoculated fruits, the extract applied to nectarines was not protective against brown rot development from M. laxa, while for apricots effects were similar to those of the negative control for P. digitatum [35]. Dichloromethane and diethyl ether T. officinale extracts were tested on P. expansum by applying either a solution or its vapor to paper discs. The dichloromethane extract was more active of the two models, though direct inoculation in apples offered no observable inhibition [26]. Water extracts of T. officinale and T. platycarpum were tested against C. lagenarium in cucumber, exhibiting inhibition rates of the anthracnose lesions of 1.9 and 13% in treated leaves, and 11 and 5.3% in untreated leaves, respectively. These results were not significant compared to other plant extracts [42]. In vivo evaluation of protective effects in plant tissue has not been as successful as the in vitro assays, which is typical in cases of inhibitory activity validation. To avoid these ineffective results,

Regarding animal pathogens, Saprolegnia infections can account for significant salmonid losses. Treatment is difficult and there are reservations regarding efficacy, prompting a search for suitable alternatives. A T. officinale root extract was not as effective as a fungistatic at 10, 100, 1000, or 10,000 mg/mL [61]. The effects of Taraxacum polysaccharides were studied on the preservation of white shrimp (Penaeus vannamei) during refrigerated storage (10 days at 4C) by soaking the shrimps in aqueous extracts (1–3% w/v). Samples were periodically evaluated for total viable count, pH value, and total volatile basic nitrogen, which resulted in 2–3% of shrimp in fresh conditions (<30 mg/100 mg of total volatile basic nitrogen) and a total viable count that only increased slightly during storage. This indicated that the treatment effectively

and R. solani at 5 mg/disc and a water extract displayed no activity at all [56].

concentrations are increased to demonstrate the pathogen control effect.

Innate plant immunity involves various defense responses, including cell wall reinforcements, lytic enzyme biosynthesis, secondary metabolite production, and pathogenesis-related proteins. To protect themselves from non-beneficial microorganisms, plants accumulate secondary metabolites that form chemical barriers to microbial attacks (phytoanticipins) and produce antimicrobials (phytoalexins) [80]. Phenolics and terpenoids are considered the primary mechanisms for plant defenses because these reduce microbial attacks by disrupting the cell membranes in microorganisms, bind to adhesins and cell wall compounds, and inactivate enzymes, among other roles [81]. The action mechanisms of natural compounds are related to the disintegration of the cytoplasmic membrane and destabilization of the proton motive force, electron flow, active transport, coagulation of the cell content, inhibition of protein synthesis, inhibition of DNA synthesis, and the synthesis of metabolites used for DNA synthesis [82]. Some action mechanisms are specific to certain targets and some targets may also be affected by more than one mechanism [83]. A general scheme of the action's sites and antimicrobial potential mechanism is presented in Figure 1 of Supporting Information.

Even though Taraxacum is a plant with extremely high pathogen resistance, the underlying molecular mechanisms of antimicrobial activity are poorly studied [68]. Until now, most of the research on Taraxacum has focused on elucidating the compounds present in the extract, and, to a lesser extent, on the mechanism involved in the antimicrobial activity itself. One study specifically illustrated the effect of four proteins from T. officinale flowers on fungi by light microscopy and distinguished two modes of antimicrobial action, depending on the fungus tested. Taraxacum proteins completely blocked conidia germination or induced thickening of multiple local hyphae and irreversible cytoplasm plasmolysis [68, 69]. Different extracts from this genus showed positive inhibitory activity in controlled studies and were characterized by protein synthesis inhibition (e.g. chloramphenicol, tetracycline, gentamicin, and kanamycin) and cell wall synthesis (e.g. amphotericin, cefixime, cephalothin, and penicillin). These

chemical identification of the obtained extracts and this identification is chiefly qualitative (e.g. using colorimetric methods indicating presence or absence). Authors report the presence of terpenoids, triterpenoids, steroids, coumarins, phenols, saponins, flavonoids, flavones, flavonols, chalcones, phlobatannins, and cardiac glycosides in antimicrobial extracts [22, 27, 34, 36, 37, 43–45, 87, 88] but neither compound isolation nor further identification were performed. Taraxasterol acetate, lupeol acetate, tranexamic acid, and squalene, among others, were identified in the dichloromethane extract of T. officinale leaves, which show low activity against E. coli, P. aeruginosa, B. subtilis, C. albicans, and T. mentagrophytes in an agar well assay at 30 μg but no observed activity against S. aureus or A. niger [27]. Terpenoids and flavonoids were identified in the ethanolic extracts of the T. farinosum root, which displayed antibacterial activity against S. aureus, S. typhi, M. canis, and T. longifusus in an agar well diffusion and agar tube dilution, while the herb extract was active only against the latter two strains [51]. Fractions of a methanolic root extract indicated the significant presence of phenolic-based compounds and hydroxyl-fatty acids with liquid and mass spectrometry, and were active against S. aureus, MRSA clinical, and B. cereus at 2 mg/mL, with MIC values ranging from 0.05 to 0.19 mg/mL, and crude extracts indicating values of 0.25–0.5 mg/mL [33]. An oligosaccharide extract (DOs) from this species exhibited high antibacterial activity against E. coli, B. subtilis, and S. aureus at 100 mg/mL, indicating that these oligosaccharides could potentially be used as antibacterial agents [48].

*Taraxacum* Genus: Potential Antibacterial and Antifungal Activity

http://dx.doi.org/10.5772/intechopen.71619

261

Concerning specific compounds, isolated Taraxacum peptides displayed antimicrobial activity at 6 μg/μL, corresponding to 52–79% of kanamycin activity against P. syringae, B. subtilis, and X. campestris at the same concentration [69], which is a promising value that warrants further experiments. These authors indicated that though A. niger appeared sensitive to four proteins (ToAMP1, ToAMP2, ToAMP3, and ToAMP4) from T. officinale flowers, F. graminearum was not susceptible to any of these proteins. All proteins displayed inhibition activity against B. cinerea, B. sorokiniana, A. niger, P. debaryanum, F. oxysporum, and P. infestans, with IC50 values ranging between 1.2 and 5.8 μM. The ToAMPs were also active against P. syringae, B. subtilis, and X. campestris, similar to a kanamycin control. Additionally, ToAMP2 was active against C. michiganensis at up to 0.5 μg/μL. The disease development of P. infestans was inhibited by ToAMP2 at 1.3 μM (20–40%) to 5.2 μM (10–20%). In further studies, B. sorokiniana, C. gloeosporioides, and V. albo-atrum were insensitive to ToAMP4, another peptide isolated from the seed extract of T. officinale, at concentrations below 15 mM. The IC50 values for the agentsensitive fungi A. alternata, A. niger, F. avenaceum, and P. betae ranged from 2.9 to 13.1 mM, with MIC values from 1.0 to 8.0 mM; no activity was observed for P. syringae, B. subtilis, E. coli, or C. michiganensis [68, 69]. Peptides supposedly have broad-spectrum activity, lack of microbial resistance, and high efficacy [69], but some action mechanisms in these molecules are still poorly defined [89]. Peptides related to albumin 2S from Taraxacum seeds are active against phytopathogenic fungi and bacteria. Antifungal assays displayed different activities for the 2S isoforms (ToA1, ToA2, and ToA3). The spore germination of B. cinerea, A. niger, and P. debaryanum were the most tolerant, and H. sativum, P. betae, and V. albo-atrum were the most sensitive at concentrations ranging from 0.063 mg/mL to 0.25 mg/mL. H. sativum and P. betae were inhibited by ToA1, ToA2, and ToA3, but F. oxysporum and V. albo-atrum were only inhibited by ToA2 and ToA3, respectively. In potato tubers, P. infestans was inhibited by ToA3 at 0.06 mg/mL at 96 and 120 h, but at 144 h ToA2 inhibited better at 0.13 mg/mL [23].

Figure 1. Main action mechanisms for antimicrobial agents (adapted from Mulvey and Simor [84]).

mechanisms need to be addressed to elucidate the Taraxacum active compound action mechanisms because a direct relation with the positive controls cannot be pursued.

Another response that has been studied is the modulation of microbe adherence to body tissues. Adhesion to epithelial cells has been represented as the first step in the subsequent bacterial invasion of host cells [59]. These authors reported the partial inhibition of intestinal adherence of C. jejuni HT-29 cells using a commercial ethanolic Taraxacum extract. Cytotoxic activity was less than 10%, but no antibacterial activity was observed. Moreover, Taraxacum has been tested with the aim of controlling bacterial diseases by inhibiting communication between bacteria. An ethanolic extract of T. officinale aerial parts disturbed bacterial communication systems (or quorum sensing) for C. violaceum, showing the moderately positive effect of the extract on the attenuation of microbial pathogenicity [30]. In contrast, an ethanolic and water extract of the rhizomes of the same plant showed no significant activity in the same assay [65].

#### 2.4. Taraxacum compounds related to antimicrobial action

Several studies have named a wide range of compounds, including terpenes, flavonoids, and phenolic compounds, as responsible for the medicinal activity of different plants [85, 86]. For Taraxacum, only a few studies concerning its antimicrobial properties have considered chemical identification of the obtained extracts and this identification is chiefly qualitative (e.g. using colorimetric methods indicating presence or absence). Authors report the presence of terpenoids, triterpenoids, steroids, coumarins, phenols, saponins, flavonoids, flavones, flavonols, chalcones, phlobatannins, and cardiac glycosides in antimicrobial extracts [22, 27, 34, 36, 37, 43–45, 87, 88] but neither compound isolation nor further identification were performed.

Taraxasterol acetate, lupeol acetate, tranexamic acid, and squalene, among others, were identified in the dichloromethane extract of T. officinale leaves, which show low activity against E. coli, P. aeruginosa, B. subtilis, C. albicans, and T. mentagrophytes in an agar well assay at 30 μg but no observed activity against S. aureus or A. niger [27]. Terpenoids and flavonoids were identified in the ethanolic extracts of the T. farinosum root, which displayed antibacterial activity against S. aureus, S. typhi, M. canis, and T. longifusus in an agar well diffusion and agar tube dilution, while the herb extract was active only against the latter two strains [51]. Fractions of a methanolic root extract indicated the significant presence of phenolic-based compounds and hydroxyl-fatty acids with liquid and mass spectrometry, and were active against S. aureus, MRSA clinical, and B. cereus at 2 mg/mL, with MIC values ranging from 0.05 to 0.19 mg/mL, and crude extracts indicating values of 0.25–0.5 mg/mL [33]. An oligosaccharide extract (DOs) from this species exhibited high antibacterial activity against E. coli, B. subtilis, and S. aureus at 100 mg/mL, indicating that these oligosaccharides could potentially be used as antibacterial agents [48].

Concerning specific compounds, isolated Taraxacum peptides displayed antimicrobial activity at 6 μg/μL, corresponding to 52–79% of kanamycin activity against P. syringae, B. subtilis, and X. campestris at the same concentration [69], which is a promising value that warrants further experiments. These authors indicated that though A. niger appeared sensitive to four proteins (ToAMP1, ToAMP2, ToAMP3, and ToAMP4) from T. officinale flowers, F. graminearum was not susceptible to any of these proteins. All proteins displayed inhibition activity against B. cinerea, B. sorokiniana, A. niger, P. debaryanum, F. oxysporum, and P. infestans, with IC50 values ranging between 1.2 and 5.8 μM. The ToAMPs were also active against P. syringae, B. subtilis, and X. campestris, similar to a kanamycin control. Additionally, ToAMP2 was active against C. michiganensis at up to 0.5 μg/μL. The disease development of P. infestans was inhibited by ToAMP2 at 1.3 μM (20–40%) to 5.2 μM (10–20%). In further studies, B. sorokiniana, C. gloeosporioides, and V. albo-atrum were insensitive to ToAMP4, another peptide isolated from the seed extract of T. officinale, at concentrations below 15 mM. The IC50 values for the agentsensitive fungi A. alternata, A. niger, F. avenaceum, and P. betae ranged from 2.9 to 13.1 mM, with MIC values from 1.0 to 8.0 mM; no activity was observed for P. syringae, B. subtilis, E. coli, or C. michiganensis [68, 69]. Peptides supposedly have broad-spectrum activity, lack of microbial resistance, and high efficacy [69], but some action mechanisms in these molecules are still poorly defined [89]. Peptides related to albumin 2S from Taraxacum seeds are active against phytopathogenic fungi and bacteria. Antifungal assays displayed different activities for the 2S isoforms (ToA1, ToA2, and ToA3). The spore germination of B. cinerea, A. niger, and P. debaryanum were the most tolerant, and H. sativum, P. betae, and V. albo-atrum were the most sensitive at concentrations ranging from 0.063 mg/mL to 0.25 mg/mL. H. sativum and P. betae were inhibited by ToA1, ToA2, and ToA3, but F. oxysporum and V. albo-atrum were only inhibited by ToA2 and ToA3, respectively. In potato tubers, P. infestans was inhibited by ToA3 at 0.06 mg/mL at 96 and 120 h, but at 144 h ToA2 inhibited better at 0.13 mg/mL [23].

mechanisms need to be addressed to elucidate the Taraxacum active compound action mecha-

Another response that has been studied is the modulation of microbe adherence to body tissues. Adhesion to epithelial cells has been represented as the first step in the subsequent bacterial invasion of host cells [59]. These authors reported the partial inhibition of intestinal adherence of C. jejuni HT-29 cells using a commercial ethanolic Taraxacum extract. Cytotoxic activity was less than 10%, but no antibacterial activity was observed. Moreover, Taraxacum has been tested with the aim of controlling bacterial diseases by inhibiting communication between bacteria. An ethanolic extract of T. officinale aerial parts disturbed bacterial communication systems (or quorum sensing) for C. violaceum, showing the moderately positive effect of the extract on the attenuation of microbial pathogenicity [30]. In contrast, an ethanolic and water extract of the rhizomes of the same plant showed no significant activity in the same

Several studies have named a wide range of compounds, including terpenes, flavonoids, and phenolic compounds, as responsible for the medicinal activity of different plants [85, 86]. For Taraxacum, only a few studies concerning its antimicrobial properties have considered

nisms because a direct relation with the positive controls cannot be pursued.

Figure 1. Main action mechanisms for antimicrobial agents (adapted from Mulvey and Simor [84]).

2.4. Taraxacum compounds related to antimicrobial action

assay [65].

260 Herbal Medicine

Interestingly, an antimicrobial filtrate isolated from the fungal strains of P. betae (PG23) from T. mongolicum was proven active against E. coli, S. aureus, A. hydrophila, E. tarda, and P. multocida, and proposed as a potential antimicrobial product for poultry and aquatic disease control [88].

Author details

References

Rolando Chamy Maggi<sup>1</sup>

Valparaíso, Valparaíso, Chile

20120207113423

10.1556/EuJMI.3.2013.4.6

DOI: 10.1007/s12033-012-9569-9

853. DOI: org/10.4141/P01-010

10.1016/j.jep.2005.12.035

2006.07.021

María Eugenia Martínez Valenzuela<sup>1</sup>

Católica de Valparaíso, Valparaíso, Chile

\*

\*Address all correspondence to: rolando.chamy@pucv.cl

, Katy Díaz Peralta<sup>2</sup>

1 Escuela de Ingeniería Bioquímica, Facultad de Ingeniería, Pontificia Universidad Católica de

2 Departamento de Química, Universidad Técnico Federico Santa María, Valparaíso, Chile

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[6] González-Castejón M, Visioli F, Rodríguez-Casado A. Diverse biological activities of dandelion. Nutrition Reviews. 2012;70:534-547. DOI: 10.1111/j.1753-4887.2012.00509.x [7] Schütz K, Carle R, Schieber A. Taraxacum – A review on its phytochemical and pharmacological profile. Journal of Ethnopharmacology. 2006;107:313-323. DOI: 10.1016/j.jep.

[8] Li G.Pharmacology, toxicity and clinic of traditional Chinese medicine. In: Tianjin Science and Technique. Tianjin, China: Translation Publishing House; 1992. pp. 207-208

3 Escuela de Ingeniería en Construcción, Facultad de Ingeniería, Pontificia Universidad

, Lorena Jorquera Martínez<sup>3</sup> and

http://dx.doi.org/10.5772/intechopen.71619

263

*Taraxacum* Genus: Potential Antibacterial and Antifungal Activity
