Phenolic Compounds fromBaseonema acuminatumLeaves: Isolation and Antimicrobial Activity

Abstract

Three new phenolic compounds, 1-galloyl-beta-D-glucopyranosyl-(1-->4)-beta-D-galactopyranoside (1), 2-methoxy-5-(1 '2 3'-trihydroxypropyl)-phenyl- 1-0-(6"-galloyl)-beta-D-glucopyranoside (2),and 2-methoxy-5-hydroxymethyl-phenyl-1-O-(6"-galloyl)-beta-D-glucopyranoside (3), together with the known compounds benzyl 6'-O-galloyl-beta-D-glucopyranoside (4), 1,6-di-O-galloyl-beta-D-glucopyranose (5), myrciaphenone B (6), kaempferol 3-0-(6"-galloyl)-beta-D-glucopyranoside (7), quercetin 3-0-(6"-galloyl)-beta-D-glucopyranoside (8), vomifoliol 9-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside, 2,3-dihydrobenzofuran-2-(4'-hydroxy-3'-methoxyphenyl)-3-alpha-L-rhamnopyranosyloxymethyl-7-methoxy-5-propanol, and benzyl-O-alpha-L-rhamnopyranosyl-(1-->6)-Beta-D-glucopyranoside were isolated from the leaves of Baseonema acuminatum P. Choux (Asclepiadaceae). Their structures were determined by 1D- and 2D-NMR spectroscopy and by ESI-MS analysis. The antimicrobial activity of all compounds was evaluated in vitro against bacteria (Staphylococcus aureus two strains, Bacillus cereus, Bacillus subtilis, Escherichia coli, Salmonella thyphimurium) and three strains of Candida albicans. The new compounds 2 and 3, together with the known compound 4, showed antifungal activity against two clinically isolated Candida albicans strains and against C. albicans ATCC 2091; MIC values were in the range of 25-100 microg/mL. Compound 5 was active against the two clinically isolated strains of C. albicans with MICs of 12.5 microg/mL and 25 microg/mL. Compounds 1, 6, 7, and 8 inhibited only one strain of C albicans at the maximum concentration used. None of the phenolic compounds tested was active against the bacteria studied.

Brazilian Copaifera Species: Antifungal Activity against Clinically Relevant Candida Species, Cellular Target, and In Vivo Toxicity

“…are rich in galloylquinic acids and flavonoids ( Figure 1 ) [ 5 ]. De Leo et al [ 30 ] reported that phenolic compounds, mostly galloylquinic acid derivatives and flavonoids, were isolated from Baseonerna acuminatum P. Choux ( Asclepiadaceae ). According to these authors, 2-methoxy-5-(1′,2′,3′-trihydroxypropyl)-phenyl-1- O -(6″-galloyl)-beta- d -glucopyranoside, 2-methoxy-5-hydroxymethyl-phenyl-1- O -(6″-galloyl)-beta- d -glucopyranoside, benzyl 6′- O -galloyl-beta- d -glucopyranoside, and 1,6-di- O -galloyl-beta- d -glucopyranose were active against clinical and ATCC Candida albicans strains.…”

Antibacterial Galloylated Alkylphloroglucinol Glucosides from Myrtle (Myrtus communis)

“…An oxidative deglucosidation would convert gallomyrtucommulones C and D ( 3c and 3d ) into the G3 precursor 5 (Scheme ), making it of interest to evaluate the physiological relationship (if any) between G3 and these compounds. On the other hand, it was also interesting to investigate the antibacterial activity of gallomyrtucommulones, since powerful antibiotic activity has been shown for several phloroglucinols from myrtle. , All compounds were evaluated against a panel of resistant Staphylococcus aureus strains (Table ), and these included MRSA strains XU212 (which also expresses the TetK efflux pump) and EMRSA-15 (which is an epidemic MRSA strain commonly encountered in the U.K.). Other isolates included the multidrug-resistant SA-1199B, which overexpresses the NorA MDR efflux transporter, and RN4220, which has a more specific macrolide efflux mechanism.…”

Enhancement of Calibrachoa growth, secondary metabolites and bioactivity using seaweed extracts

“…Yazdani et al [53] reported that certain phenolic compounds isolated from the methanolic extracts of Piper betle L. (Piperaceae) could inhibit the growth of A. flavus . Phenolics isolated from the root bark of Lycium chinense Miller (Solanaceae) [54], the leaves of Baseonema acuminatum (Apocynaceae) [55], and the leaves of Hyssopus officinalis [56] have been associated with the antifungal and antioxidant activities. The bioactivity of phenolic compounds might be attributed to the interferece with proteins and forming non-covalent bonds leading to conformation changes and protein inactivation in microbes [57].…”