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Flamvelutpenoids A–D (1–4), four new cuparene-type sesquiterpenes, were isolated from the solid culture of Flammulina velutipes. Their structures were elucidated by NMR experiments. The absolute configurations of 1 and 2 were assigned via the circular dichroism data of the [Rh2(OCOCF3)4] complex, whereas that of C(3) of 3 was determined by applying the octant rule for the α,β-unsaturated ketone moiety. Compounds 1–4 showed weak antibacterial activity against Escherichia coli, Bacillus subtilis, and methicillin-resistant Staphylococcus aureus with MIC values larger than 100 μM.

Seventeen daucane sesquiterpenoid esters, including a new one (4), were isolated from the root of Ferula hermonis Boiss. The structures of the isolated compounds were elucidated on the basis of spectroscopic evidence and correlated with known compounds. The relative stereochemistry of the new compound was determined using 2D NOESY and the most stable and the lowest energy conformation was determined using molecular modelling. The antimicrobial activity was evaluated by determination of MIC using the broth microdilution method against six bacterial strains and one fungal strain (Pseudomonas aeruginosa PAO1, Escherichia coli, Bacillus subtilis ATCC6633, Mycobacterium bovis BCG Pasteur, Mycobacterium tuberculosis H37Rv, Staphylococcus aureus ATCC6538 and Candida albicans SC5314). There was a significant indication that compounds 15, 16, 17 demonstrated potent activity against Gram +ve (S. aureus, B. subtilis), as well as Mycobacterium strains M. bovis BCG and M. tuberculosis H37Rv. None of the isolated compounds exhibited a significant antifungal activity. In the antioxidant study using the DPPH assay method, the highest radical scavenging activity was observed for compounds 15, 16, 17.

Membranes based on poly[2,2'-(p-oxydiphenylene)-5,5'-bibenzimidazole] (OPBI) and their sulphonated derivatives (SOPBI) were prepared and first investigated for high temperature proton exchange membrane fuel cells. OPBI and SOPBI membranes with good chemical stability were prepared by casting from their dimethyl sulphoxide ( DMSO) solution and then impregnated in phosphoric acid baths to obtain H(3)PO(4) (PA)-doped membranes. The properties of PA-doped OPBI membranes, including phosphoric acid uptake, swelling ratio, mechanical properties and thermal properties, were fully investigated and compared with PA-doped SOPBI membranes. The fuel cell performances of PA-doped OPBI and SOPBI membranes at different temperatures were first evaluated. When doped in different concentrations of H(3)PO(4) solution, OPBI membranes adsorb more acid than SOPBI membranes. SOPBI membranes exhibit obviously lower swelling ratio in thickness direction than that of OPBI membranes. With an acid uptake of similar to 110 wt.%, corresponding doping level around 5, PA-doped OPBI and SOPBI membranes keep reasonably high tensile strength. PA-doped OPBI membranes exhibit peak power density of 0.78 W cm(-2) at 170 degrees C and 0.25 MPa. With the same acid uptake, PA-doped SOPBI membranes displayed similar fuel cell performance to that of PA-doped OPBI membranes.

Investigation on the extracts of Hydnocarpus anthelminthica seeds led to the isolation of three new compounds, anthelminthicins A-C (1-3, resp.), and two known ones, namely chaulmoogric acid (4) and ethyl chaulmoograte (5). Their structures were determined mainly by using spectroscopic techniques. The absolute configuration at the cyclopentenyl moiety of compound 2 was rationalized by quantum calculations. Base hydrolysis, followed by optical-rotation comparison, allowed assignment of the configuration of chaulmoogric-acid moiety of compounds 3 and 5. Biological assays revealed that compounds 1-5 significantly inhibit Mycobacterium tuberculosis (MTB) growth with MIC values of 5.54, 16.70, 4.38, 9.82, and 16.80 microM, respectively. Compound 3 was found to inhibit the pathway between chorismate and para-aminobenzoic acid (pAba) with a MIC value of 11.3 microM, representing a new example of pAba inhibitor isolated from a natural source. All compounds were not toxic to Candida albicans SC5314 at a concentration up to 100 microM.

Three new polyketide metabolites, the twelve-membered macrolides (6R,12S)-6-hydroxy-12-methyloxacyclodoecane-2,5-di one (1), (10S,12S)-10-hydroxy-12-methytoxacyclododecane-2,5-dione (2), and 4,5-dihydroxy-12-methytoxacyclododecan-2-one (3), were isolated from the endophytic fungal strain Cladosporium tenuissimum LR463 of Maytenus hookeri, together with three known compounds, cladospolide A, cladospolide B, and isocladospotide B. Their structures were elucidated by spectroscopic analysis including 1D- and 2D-NMR experiments, and the absolute configurations of 1. and 2 were determined by the Mosher ester method.

Microbial metabolites have been an important source of tuberculosis (TB) therapeutics, but the last truly novel drug that was approved for the treatment of TB was discovered 40 years ago. In light of the growing threat of multi-drug resistance, recent advances have been made to accelerate the discovery rate of novel TB drugs including diversifying strategies for environmental strains, and high-throughput screening assays. This review will discuss the approaches used in biodiversity- and taxonomy-guided microbial natural product library construction, specific cell-based and target-based high-throughput screening assays and early-stage dereplication processes by liquid chromatography-mass spectrometry (LC-MS). New antituberculosis natural products that have been recently discovered are highlighted.