Antifungal and antibacterial activities of Mexican tarragon (Tagetes lucida).
Mexican tarragon (Tagetes lucida Cv. Asteraceae: Campanulatae) is an important, nutritious plant and an effective herbal medicine. Seven coumarins, 7,8-dihydroxycoumarin (4), umbelliferone (7-hydroxycoumarin) (5), scoparone (6,7-dimethoxycoumarin) (7), esculetin (6,7-dihydroxycoumarin) (11), 6-hydroxy-7-methoxycoumarin (12), herniarin (7-methoxycoumarin) (13), and scopoletin (6-methoxy-7-hydroxycoumarin) (14), and three flavonoids, patuletin (18), quercetin (19), and quercetagetin (20), were isolated from CH2Cl2 and MeOH extracts from aerial parts of T. lucida. In addition, 6,7-diacetoxy coumarin (15), 6-methoxy-7-acetylcoumarin (16), and 6-acetoxy-7-methoxycoumarin (17) derivatives were synthesized. 8-Methoxypsoralen (1), 8-acetyl-7-hydroxycoumarin (2), 7,8-dihydroxy-6-meth-oxycoumarin (3), 6,7-dimethoxy-4-methylcoumarin (6), 5,7-dihydroxy-4-methylcoumarin (8), 4-hydroxycoumarin (9), 4-hydroxy-6,7-dimethylcoumarin (10), naringenin (21), glycoside-7-rhamnonaringin (22), and rutin (23) were commercially obtained (Sigma-Aldrich). All of these compounds and extracts (M1 and M2) were assayed against bacteria and fungi. The antibacterial activity was determined on Bacillus subtilis, Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, Salmonella typhi, Salmonella sp., Shigella boydii, Shigella sp., Enterobacter aerogenes, Enterobacter agglomerans, Sarcina lutea, Staphylococcus epidermidis, Staphylococcus aureus, Yersinia enterolitica, Vibrio cholerae (three El Tor strains, CDC-V12, clinic case, and INDRE-206, were obtained from contaminated water), and V. cholerae (NO-O1). The evaluated fungi were Aspergillus niger, Penicillium notatum, Fusarium moniliforme, Fusarium sporotrichum, Rhizoctonia solani, and Trichophyton mentagrophytes. The most active compounds against Gram-positive and -negative bacteria were the dihydroxylated coumarins 3 and 4. In addition, 2-4, 6, 7, and 11 showed an interesting activity against V. cholerae, a key bacterium in the contaminated water; 2-4 were the most active. Coumarins were the most effective compounds against Gram-negative bacteria. The extract MeOH/CH2Cl2 (1: 4) M2 at 0.4 microg/disk inhibited the growth of E. coli and P. mirabilis (40%), K. pneumoniae (31.1%), Salmonella sp. (35.5%), and Shigella sp. (0%) at 72 h of culture. The dimethoxy compounds 6 and 7 showed a strong activity against fungal strains, especially T. mentagrophytes and R. solani (100% of inhibition at 125.0 and 250.0 microg/mL, respectively).
Céspedes
Carlos L
CL
Laboratorio de Fitoquímica, UBIPRO FES-Iztacala, Universidad Nacional Autónoma de Mexico, Avenida de los Barrios S/N, Los Reyes Iztacala, Tlalnepantla, Estado de Mexico, C. P. 5409, México. cespedes_leonardo@yahoo.com
Avila
J Guillermo
JG
Martínez
Andrés
A
Serrato
Blanca
B
Calderón-Mugica
José C
JC
Salgado-Garciglia
Rafael
R
D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D003374:Coumarins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D019587:Dietary Supplements; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D005658:Fungi / Q000187:drug effects; D015394:Molecular Structure; D035261:Plant Components, Aerial / Q000737:chemistry; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D031686:Tagetes / Q000737:chemistry*
D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D003374:Coumarins; D005419:Flavonoids; D010936:Plant Extracts