Two bisdihydroanthracenone atropodiastereomeric pairs, including homodimeric flavomannin A (1) and the previously unreported flavomannin B (2), two new unsymmetrical dimers (3 and 4), and two new mixed dihydroanthracenone/anthraquinone dimers (5 and 6) were isolated from Talaromyces wortmannii , an endophyte of Aloe vera . The structures of 2-6 were elucidated by extensive NMR and mass spectrometric analyses. The axial chirality of the biaryls was determined using TDDFT ECD and VCD calculations, the combination of which however did not allow the assignment of the central chirality elements of 1. The compounds exhibited antibacterial activity against Staphylococcus aureus , including (multi)drug-resistant clinical isolates. Reporter gene analyses indicated induction of the SOS response for some of the derivatives, suggesting interference with DNA structure or metabolism. Fluorescence microscopy demonstrated defective segregation of the bacterial chromosome and DNA degradation. Notably, the compounds showed no cytotoxic activity, encouraging their further evaluation as potential starting points for antibacterial drug development.

Penicillin-binding protein 2x (PBP2x) of Streptococcus pneumoniae represents a primary resistance determinant for beta-lactams, and low-affinity PBP2x variants can easily be selected with cefotaxime. Penicillinresistant clinical isolates of S. pneumoniae frequently contain in their mosaic PBP2x the mutation T338A adjacent to the active site S337, and T338P as well as T338G substitutions are also known. Site-directed mutagenesis has now documented that a single point mutation at position T338 confers selectable levels of beta-lactam resistance preferentially to oxacillin. Despite the moderate impact on beta-lactam susceptibility,

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Chemical investigation of the endophytic fungus Botryosphaeria australis isolated from Avicennia marina originally from Hainan Province, P.R. China, yielded a new compound botryosphaenin (1), from the class of napthoquinone, together with 5 known compounds, botryosterpene (2) and 5-hydroxy-2,7-dimethoxynaphthalene-1,4-dione (3) and its derivatives, 6-ethyl-5-hydroxy-2,7-dimethoxynaphthalene-1,4-dione (4), O-methylaspmenone (5), Omethylasparvenone (6) and 5-(carboxymethyl)-7-hydroxy-1,4a-dimethyl-6-methylene decahydron aphthalene-1-carboxylic acid (7). Their structures were determined on the basis of spectroscopic methods including 1D ( 1 H, 13 C, and DEPT) and 2D (COSY, HMQC, HMBC, and ROESY) NMR experiments and by mass spectroscopic measurements The new compounds, 1 showed activity against the bacterial pathogens Staphylococcus aureus, several Streptococcus species and Bacillus subtilis, but also against the eukaryotic cell lines THP-1 (human leukemia monocyte) and BALB/3T3 (mouse embryonic fibroblast). Keywords: Mangrove, Avicennia marina, Botryosphaeria australis, antibiotic activities, cytotoxicity ABSTRAK Telah dilakukan penelitian kimiawi tentang jamur endofit Botryosphaeria australis yang diisolasi dari bakau Avicennia marina yang tumbuh di kawasan Provinsi Hainan, Republik Rakyat China. Dari penelitian ini diperoleh senyawa botryosphaenin (1), yang merupakan senyawa baru , dari kelas napthoquinone , bersama dengan lima senyawa yang diketahui sebelumnya yaitu, botryosterpene (2) dan 5 -hidroksi -2,7 -dimetoksinaftalen -1 ,4 -dion (3) dan turunannya , 6 -etil -5 -hidroksi -2 ,7 -dimetoksinaftalen -1 ,4 -dion (4) , O -metilaspmenon (5) , O -metilasparvenon (6) dan 5 -( karboksimetil ) -7 -hidroksi -1 , asam 4a -dimetil -6 -1 -metilendekahidronaftalen karboksilat (7). Strukturnya kimia dari senyawa-senyawa tersebut di atas ditentukan berdasarkan analisis spektroskopi Resonansi Magnetik Inti (NMR) termasuk 1D (1H , 13C, dan DEPT) dan 2D ( COSY, HMQC, HMBC, and ROESY) serta menggunakan spektroskopi massa. Senyawa baru yang diisolasi (1) tidak hanya menunjukkan aktivitas yang kuat melawan bakteri patogen Staphylococcus aureus, beberapa spesies Streptococcus dan Bacillus subtilis, tetapi juga terhadap galur sel eukariotik THP -1 (human leukemia monocyte) dan BALB/3T3 (mouse embryonic fibroblast) .

Absolute Configuration and Antibiotic Activity of Neosartorin (I) from the Endophytic Fungus Aspergillus fumigatiaffinis. -The title compound (I) exhibits substantial antibacterial activity against a broad spectrum of Gram-positive bacterial species (e.g. staphylococci, streptococci, enterococci, B. subtilis) and toxicity against the cancer cell lines HeLa and BALB/3T3 (IC 50 = 32 g/mL). -(OLA, A. R. B.; DEBBAB, A.; ALY, A. H.; MANDI, A.; ZERFASS, I.; HAMACHER, A.; KASSACK, M. U.; BROETZ-OESTERHELT, H.; KURTAN, T.; PROKSCH*, P.; Tetrahedron Lett. 55 (2014) 5, 1020-1023, http://dx.