Potential anti-inflammatory diterpenoids from the roots of Caesalpinia mimosoides Lamk.

Anti-inflammatory assay-guided separation of extracts from the roots of Caesalpinia mimosoides Lamk. led to isolation of seven compounds: four diterpenes (1–4), a dimer (9), and two dibenzo[b,d]furans (10, 11) together with eleven known compounds. Their structures were elucidated by 1D- and 2D-NMR techniques as well as UV, IR, mass spectral data and comparison with literature values. The anti-inflammatory activities of all compounds were evaluated for inhibitory activities against lipopolysaccharide (LPS) induced nitric oxide (NO) production in RAW264.7 cell lines. Compounds 4, 6, 8, and 12–14 were also tested for the inhibitory effect on LPS-induced tumor necrosis factor-alpha (TNF-α) release in RAW264.7 cells. The results indicated that 4 possessed potent inhibitory activity for both tests with IC₅₀ values of 3.0 and 6.5 μM, respectively.     

Proteomic analysis of a thermostable superoxide dismutase from Bacillus stearothermophilus TLS33

Thermophilic bacterium Bacillus stearothermophilus TLS33 isolated from a hot spring in Chiang Mai, Thailand produces an extracellular superoxide dismutase (SOD). SOD is a free radical metabolizing enzyme that protects the cell membrane from damage by the highly reactive superoxide free radicals. To identify the secreted SOD, we used the systematically proteomic approaches of two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) analysis and database searching. The bacterium was grown in a medium containing 0.1% w/v yeast extract and 0.1% w/v tryptone in 100% v/v base mixture at 65 degrees C for 72 h, by assessing their growth by protein and SOD activity. The bacterium produced the highest SOD activity at 65 degrees C for 48 h and the extracellular SOD was run on 2-D PAGE using broad range pH 3-10 immobilized pH gradients (IPGs) and narrow range pH 4-7 IPGs. The isoelectric point and molecular mass of the extracellular SOD were approximately 5.8 and 28 kDa, respectively. In addition, the NH(2)-terminal amino acid sequence was found to be P-F-E-L-P-A-L-P-Y-P-Y-D-A-L-E-P-P-I-I-D, which had a homology of approximately 85% to the Mn-SOD family and 65% to the Fe-SOD family.     

Potential anti-allergic ent-kaurene diterpenes from the bark of Suregada multiflora

Two ent-kaurene diterpenes, ent-16-kaurene-3beta,15beta,18-triol (1) and ent-3-oxo-16-kaurene-15beta,18-diol (2), were isolated from a dichloromethane extract of the bark of Suregada multiflora along with five known diterpenes:ent-16-kaurene-3beta,15beta-diol (3), abbeokutone (4), helioscopinolide A (5), helioscopinolide C (6) and helioscopinolide I (7). Their structures were elucidated on the basis of spectroscopic analysis. Compounds 1-7 possessed appreciable anti-allergic activities in RBL-2H3 cells model with IC50 values ranging from 22.5 to 42.2 microM.     

Phanginin A-K, diterpenoids from the seeds of Caesalpinia sappan Linn

The first chemical study on the seeds of Caesalpinia sappan Linn. led to isolation of 11 cassane-type diterpenes, named phanginin A-K (1-11). The skeleton present in compounds 1-8 is rather unusual, consisting of a cassane-type diterpene with an ether bridge between C-19/C-20 in compounds 1-6 and C-11/C-20 in compounds 7 and 8. Their structures were elucidated on the basis of spectroscopic techniques. In addition, the X-ray structure of phanginin A (1) is reported. Only phanginin I (9) exhibited cytotoxic effect against KB cell line with IC50 value of 4.4 microg/ml.