Sesquiterpenes antibacterial activity

A1 Dabbas et al. [163] reported the antibacterial activity of the ethyl acetate extract of the whole aerial part of Varthemia iphinoides L. The bioassay-guided fractionation led to the isolation and identification of an antibacterial eudesmane sesquiterpene, selina-4,ll(13)-dien-3-on-12 oic acid. Fig. (10). This compound exhibited potent antimicrobial activity against 6 bacterial species Staphylococcus aureus, Bacillus subtilis. Micrococcus luteus, Escherichia coli. Bacillus cereus and Salmonella enter Hides ). The MIC values of this sesquiterpene, which was determined by the agar dilution method, ranged between 250 and 500 ig/ml. 

Antibacterial bisabolane sesquiterpenes and tricyclic sesquiterpenes, the latter consisting of an irregularly built C15 backbone, were also isolated from Leontopodium alpinum [36]. These compounds showed significant antibacterial activity towards Enterococcus faecium. 

An ethanol extract of the leaves showed cytotoxicity to mammalian cells in vitro and weak in vitro antibacterial activity against Gram-positive and Gram-negative organisms. Numerous sesquiterpene lactones (e.g., eupatilin, eupafolin, eupatorin acetate, and eupaformosanin) and flavones (especially eupatorin) isolated from Eupatorium species have shown cytotoxic and/or antineoplastic activities. ... 

Three imusual sesquiterpenes related to guaiane skeleton were characterized in Ulvafasdata from India. All of these result from transpositions of the original carbon skeleton, and all have antibacterial activities against three strains of aquacultural pathogens Vibrio al nolyticus, V. parahaemolyticus, and V. vulnificus (Chakraborty et al., 2010). 

Bansemir, A., Just, N., Michalik, M., Lindequist, U., and Lalk, M. (2004) Extracts and sesquiterpene derivatives from the red alga Laurencia chondrioides with antibacterial activity against fish and human pathogenic bacteria. Chem. Biodiv., 1, 463-467. 

Vairappan, C.S., Suzuki, M., Ishii, T, Okino, T, Abe, T, and Masuda, M. (2008) Antibacterial activity of halogenated sesquiterpenes from Malaysian Laurencia sp. Phytochemistry, 69, 2490-2494. 

Although the first survey listed 45 natural chlorinated sesquiterpene lactones, several such compounds were omitted in that coverage (1) and are described here. The novel sesquiterpene lactone chlorochrymorin (239) was isolated from Chrysanthemum morfolium (499), and the chlorohydrin graminichlorin (240) is found in Liatris graminifolia (500). The antibacterial AA-57 (241), which is related to pentalenolactone, is produced by a Streptomyces sp. (501). The plant Eupatorium chinense var. simplicifolium has yielded eupachifolin D (242) (502) (side-chain double bond stereochemistry revised (518)), and the new guaianolide andalucin (243) was characterized from Artemisia lanata (503). The previously known chlorohyssopifolins (1) have been studied for cytostatic activity, and the presence of one and even two chlorine atoms amplifies this activity (504). 

Other genera from the Anthemideae tribe such as Inula, Tanacetum and Xanthium also yielded sesquiterpene lactones with a broad spectrum of antibacterial and antifungal activity. Isoalantolactone, a major constituent of Inula racemosa Flook. f, was tested for its... 

Examples of other antimicrobial sesquiterpene lactones from the Anthemideae tribe also included those isolated from Anaphalis margaritacea (L.) Benth Hook., Fig. (24) [196], two new antibacterial melampolide-type sesquiterpene lactones from Smallanthus sanchifolius (Poepp. and Endl.) H. Robinson, which exhibited potent antimicrobial activity against Bacillus subtilis and Pyricularin oryzae [197], and six... 

Ilimaquinone (29) is a marine sesquiterpene quinone first isolated in 1979 from the sponge Hippospongia metachromia90 It has been reported to have mild antibacterial, antiviral, antifungal, and anti-inflammatory activities, but more interestingly, ilimaquinone has been found to break down the Golgi apparatus into small vesicles, thereby blocking cellular secretion.91 92... 

Many monoterpenes are biologically active (Fig. 19.15) (Herout, 1970 Seigler, 1983) and representatives of this group of compounds are toxic to a large number of organisms. For example, thujaplicinol (46) (Fig. 19.1) is a useful antibacterial adenyltransferase inhibitor (Croteau and Johnson, 1985). Among the biologically active terpenoids, monoterpenes and sesquiterpenes predominate. 

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