Coumarin antimicrobial activity

The activity of extracts A, C and D (Table 7) indicates a clear correlation with their hydroxycoumarin composition. The extract C enriched with the coumarins esculetin (2), fraxin (3) and fraxetin (4) shows the highest antimicrobial activity of all studied extracts. The inhibitory power of extracts C and D is comparable with that of famesol. The HPLC profiles of the tested extracts indicated the presence of some other bark constituents, different from 2-4, that could also contribute to their activity [14]. 

Further, phenolic phytochemicals can be targeted for antimicrobial applications. Many phenolic containing Ifuit and herbal products have shown to possess antimicrobial activity agdimsi Listeria monocytogenes (Chung etal. 1990 Hao et al. 1998 Puupponen-Pimia etal. 2001 Sa-gun et al. 2006). Recent research with purified compoimds from natural products has shown that phenolic phytochemicals such as cinnamic acid, cinnamaldehydes, coumarins, capsaicin, and tannins have anti-7/. pylori activity (Bae et al. 1999, 1998 Jones et al. 1997) when caffeic and gallic acid have Staphylococcus aureus inhibitory activity (Kwon etal. 2007). 

A series of new coumarin derivatives has been synthesized and the in vitro antimicrobial activity against thirteen strains of bacteria and three fungal/yeast strains were screened. They were shown to possess a wide range of activities from almost completely inactive compounds to medium active ones (Dekid et al. 2010). 

In this review we have discussed published results concerning the QSAR research on antimicrobial properties of synthetic and natural compounds. Antifungal and antimicrobial activity of some coumarin derivatives, various types of biological activities of benzamides, several studies on cinnamic acid derivatives with antibacterial and antifungal activity, reports on the biological activity of homoisoflavanones and phenolic compounds, as well as pharmaceutical applications of furan derivatives have been shown. 

T. Ojalla, S. Remes, P. Hans, Antimicrobial activity of some coumarin containing herbal plants growing in Finland, J. Ethnopharmacol. 68 (1999) 267-274. 

Creaven, B. S. Egan, D. A. Kavanagh, K. McCaim, M. Noble, A. Thati, B. Walsh, M. Synthesis, characterization and antimicrobial activity of a series of substituted coumarin-3-carboxylato silver(I) complexes. Inorg. Chim. Acta 2006, 359, 3976-3984. 

Abstract We report here the synthesis of newly coumarinic derivatives by using 4-hydroxy coumarine as starting material. These newly compounds were screened in vitro for their antimicrobial and antifungal activities. The structures of the synthesized compounds were proved by IR, H NMR, 13 C NMR and mass-spectral. 

Other antimicrobial phenolic compounds from the Anthemideae tribe are coumarins, which are derivatives of benzo-a-pyrone. Feresin et al. [199] isolated eight / -coumaric acid derivatives from the Argentinian medicinal plant Baccharis grisebachii. Two of them, 3-prenyl-/ -coumaric acid, Fig. (38) and 3,5-diprenyl-p-coumaric acid were active towards Epidermophyton floccosum and Trichophyton rubrum, with MIC values of 50 and 100-125 ig/ml, respectively. 

In addition, certain plant cells maintain high levels of antimicrobial secondary metabolites (constitutive chemicals) such as various phenols, flavenoids, alkaloids, coumarins, or cyanogenic glycosides [116, 118-120], These products are often found in strategically located sites such as epidermal tissues or latex. Some of these products are activated by... 

Their application in the biomedical field is clearly demonstrated by the preponderance of patents as compared to publications in the field. Calixarenes functionalized at the wide rim with sulfonic acid and sulfonamide groups showed anticoagulant and antithrombotic properties, approaching the activity of heparin and coumarin, currently used as anticoagulants in antithrombotic therapy. Calixarene derivatives are also active as antiviral, antimicrobial. and antifungal agents. 

Coumarins in general have antimicrobial and fungicidal activity. They are often described as blood thinning, though this activity is mainly restricted to dicoumarol, a product of incorrectly dried (or mouldy) hay. 

Isocoumarin (2) is the structural isomer of coumarin some isocumarin derivatives show antifungal, antimicrobial, and phytotoxic activities [44]. 

Hoegberg, T. Vora, M. Drake, S. D. Mitscher,L. A. Chu, D. T. W. Structure-activity relationships among DNA-gyrase inhibitors. Synthesis and antimicrobial evaluation of chromones and coumarins related to oxolinic acid. Acta Chem. Scand., Ser B 1984, B38, 359-366. 

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