A pair of unusual benzannulated 6,6-spiroketal enantiomers [(-)-1 and (+)-1] and three new biogenetically related compounds (2-4), together with two known related analogues (5 and 6), have been isolated from a mangrove fungus, Penicillium dipodomyicola HN4-3A. Their structures were elucidated on the basis of spectroscopic analysis (1D and 2D NMR data) and X-ray crystallography. The absolute configurations of enantiomers (-)-1 and (+)-1 were determined using quantum chemical calculations of the electronic circular dichroic (ECD) spectra. Compounds 2 and 3 exhibited strong inhibitory activity against Mycobacterium tuberculosis protein tyrosine phosphatase B (MptpB) with IC50 values of 0.16±0.02 and 1.37±0.05 μM, respectively.

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An unusual austinoid, 1,2-dehydro-terredehydroaustin (1), together with two known meroterpenoids (2 and 3), were isolated from the mangrove endophytic fungus Aspergillus terreus. The structures were elucidated on the basis of spectroscopic data, X-ray diffraction and ECD calculations. The anti-inflammatory activity was assayed and compound 1 exhibited weak inhibition effect against the production of nitric oxide (NO) in lipopolysaccharide (LPS)-induced RAW 246.7 mouse macrophages with an IC value of 42.3 μM.

Heavy-metal chromium [Cr(VI)] is a ubiquitous environmental pollutant. Comparing with chemical reduction, microbiological reduction is considered to be a friendly and cheaper way to decrease the damage caused by chromate. A bacterial strain, CR-07, which is resistant to and capable of reducing chromate was isolated from a mud sample of iron ore and identified as a Microbacterium sp. The bacterium had a high degree of tolerance to chromate, and could grow in LB medium containing 4.08 mM of K(2)Cr(2)O(7). It also had a degree of resistance to other heavy metals, e.g. Cd(2+), Pb(2+), Zn(2+), Cu(2+), Co(2+), Hg(2+) and Ag(+). The bacterium could remove 1.02 mM of Cr(VI) from LB medium within 36 h of incubation. Chromate removal was achieved in the supernatant from the bacterial cultures, and corresponded to chromate reduction. The activity of chromate reduction by the bacterium was not related to enzymes or reducing sugars, while fluorometric assay suggested that glutathione, a chromate-reducing substance which was produced by the bacterium, was one of the factors that contributed to the reduction of Cr(VI).