Antibacterial compound from the endophytic fungus Phomopsis longicolla isolated from the tropical red seaweed Bostrychia radicans

Endophytic fungi isolated from the red seaweed Bostrychia radicans were studied to identify their molecularly diverse and biologically active natural chemical products. According to 28S ribosomal DNA-based identification, the strain named C81 was 98% identical to Phomopsis longicolla. This strain was cultivated in solid rice medium and produced three major metabolites identified as 18-deoxycytochalasin H (1), mycophenolic acid (2), and dicerandrol C (3). The chemical structures of these compounds were elucidated by 1D and 2D nuclear magnetic resonance as well as by mass spectrometry. Dicerandrol C had significant antimicrobial activity against Staphylococcus aureus (ATCC 6538) and Staphylococcus saprophyticus (ATCC 15305), with minimum inhibitory concentrations of 1 and 2 mu g ml(-1) (1.33 and 2.66 mu M), respectively. These results show the presence of promising metabolites and indicate that these natural products should be considered in the development of new antibiotics.

CHEMICAL CONSTITUENTS FROM RED ALGAE Bostrychia radicans (Rhodomelaceae): NEW AMIDES AND PHENOLIC COMPOUNDS

This study describes the isolation and structural determination of two amides, isolated for the first time: N,4-dihydroxy-N-(2'-hydroxyethyl)-benzamide (0.019%) and N, 4-dihydroxy-N-(2'-hydroxyethyl)-benzeneacetamide (0.023%). These amides, produced by the red macroalgae Bostrychia radicans, had their structures assigned by NMR spectral data and MS analyses. In addition, this chemical study led to the isolation of cholesterol, heptadecane, squalene, trans-phytol, neophytadiene, tetradecanoic and hexadecanoic acids, methyl hexadecanoate and methyl 9-octadecenoate, 4-(methoxymethyl)-phenol, 4-hydroxybenzaldehyde, methyl 4-hydroxybenzeneacetate, methyl 2-hydroxy-3-(4-hydroxyphenyl)-propanoate, hydroquinone, methyl 4-hydroxymandelate, methyl 4-hydroxybenzoate, 4-hydroxybenzeneacetic acid and (4-hydroxyphenyl)-oxo-acetaldehyde. This is the first report concerning these compounds in B. radicans, contributing by illustrating the chemical diversity within the Rhodomelaceae family.

Natural occurrence of Zoophthora radicans (Entomophthorales: Entomophthoraceae) on Thaumastocoris peregrinus (Heteroptera: Thaumastocoridae), an invasive pest recently found in Brazil

Occurrence of Zoophthora radicans infecting nymphs and adults of Thaumastocoris peregrinus Carpintero and Dellape, 2006 is reported in Brazil. This is a new record of host for this fungal species and the first fungal pathogen associated with this pest worldwide. Infection of Z. radicans on T. peregrinus populations on commercial Eucalyptus plantation (Eucalyptus spp.) reached up to 100%, and low insect densities were associated with high levels of fungal infection in three out of seven plots. This pathogen seems to be virulent against T. peregrinus and may play an important role in population regulations of this invasive pest through naturally induced epizootics. (c) 2012 Elsevier Inc. All rights reserved.

Chemical constituents from red algae Bostrychia radicans (Rhodomelaceae): new amides and phenolic compounds

This study describes the isolation and structural determination of two amides, isolated for the first time: N,4-dihydroxy-N-(2'-hydroxyethyl)-benzamide (0.019%) and N,4-dihydroxy-N-(2'-hydroxyethyl)-benzeneacetamide (0.023%). These amides, produced by the red macroalgae Bostrychia radicans, had their structures assigned by NMR spectral data and MS analyses. In addition, this chemical study led to the isolation of cholesterol, heptadecane, squalene, trans-phytol, neophytadiene, tetradecanoic and hexadecanoic acids, methyl hexadecanoate and methyl 9-octadecenoate, 4-(methoxymethyl)-phenol, 4-hydroxybenzaldehyde, methyl 4-hydroxybenzeneacetate, methyl 2-hydroxy-3-(4-hydroxyphenyl)-propanoate, hydroquinone, methyl 4-hydroxymandelate, methyl 4-hydroxybenzoate, 4-hydroxybenzeneacetic acid and (4-hydroxyphenyl)-oxo-acetaldehyde. This is the first report concerning these compounds in B. radicans, contributing by illustrating the chemical diversity within the Rhodomelaceae family.