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Ultra‐fine fiber mats of poly(L‐lactic acid) containing gallic acid were prepared by electrospinning from gallic acid‐containing PLLA solution in 7:3 v/v dichloromethane (DCM)/N,N‐dimethylformamide (DMF). The amount of the as‐loaded gallic acid was 40% w/w (based on the weight of PLLA in the solution) or 28.6 wt.‐% (based on the weight of the resulting fiber mats). Both the neat and the gallic acid‐loaded PLLA fibers were smooth, with the average diameters of 965 and 843 nm, respectively. No aggregates of gallic acid were observed on the fiber surface and the actual amount of gallic acid in the gallic acid‐loaded PLLA fiber mats, determined in the acetate buffer, the citrate‐phosphate buffer, and the normal saline, was 26.3, 27.1, and 24.6 wt.‐%. The cumulative amount of gallic acid released from the gallic acid‐loaded PLLA fiber mats was greatest in the normal saline, followed by those in the citrate‐phosphate and the acetate buffer, respectively. Lastly, the free radical scavenging activity, based on the 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) assay, of the as‐loaded and the as‐released gallic acid remained active.magnified image

A new labdane diterpenoid, (E)-labda-8(17),12-dien-15,16-olide (1) together with eight known compounds, coronarin D (2), coronarin D methyl ether (3), coronarin D ethyl ether (4), isocoronarin D (5), coronarin B (6), labda-8(17),11,13-trien-15,16-olide (7), (E)-labda-8(17),12-diene-15,16-dial (8) and 16-hydroxylabda-8(17),11,13-trien-15,16-olide (9), are isolated from the rhizomes of Hedychium coronarium. Compounds 2-4, 5 and 9 are isolated as mixtures of C-15, C-14 and C-16 epimers, respectively. Their structures are determined on the basis of their spectroscopic data. The epimeric mixtures of 2 and 3 have not been reported before. Some of them were evaluated for their cytotoxicity.

The cytotoxic activity of five alkaloids, namely 4,5-dioxo-dehydrocrebanine (1), dehydrocrebanine (2), crebanine (3), oxostephanine (4), and thailandine (5) isolated from the tuber and leaves of Stephania venosa (Blume) Spreng was investigated. Thailandine showed the strongest activity against lung carcinoma cells (A549) (IC50 of 0.30 µg/mL) with very low cytotoxicity against normal embryonic lung cells (MRC-5). Thailandine also demonstrated strong activity against Plasmodium falciparum, K1 strain (IC50 of 20 ng/mL), and Mycobacterium tuberculosis H(37)Ra (MIC of 6.25 µg/mL) as well as gram-positive bacteria such as Streptococcus pneumoniae and Staphylococcus aureus. Oxostephanine exhibited strong activity against breast cancer (BC) and acute lymphoblastic leukemia cells (MOLT-3) with an IC50 of 0.24 and 0.71 µg/mL, respectively, and exhibited very low cytotoxicity against MRC-5 cells. Dehydrocrebanine demonstrated strong activity against promyelocytic leukemia cells (HL-60) with an IC50 of 2.14 µg/mL whereas crebanine showed weak activity against cancer cell lines. However, both of them showed cytotoxicity against MRC-5 cells.