Lanostane triterpene glycosides from the flowers of Lyonia ovalifolia var. hebecarpa and their antiproliferative activities.

Sixteen lanostane-type triterpene glycosides including eight new ones, named lyonicarposides A-H (1-8), were isolated from the flowers of Lyonia ovalifolia var. hebecarpa (Franch. ex F.B. Forbes & Hemsl.) Chun (Ericaceae). The chemical structures of the new compounds were elucidated by the comprehensive spectroscopic techniques and chemical methods. The Mo2(OAc)4-induced electronic circular dichroism method was used to determine the absolute configurations of C-24 in lyonicarposides A (1), C (3), and E (5). This is the first phytochemical study on the flowers of L. ovalifolia var. hebecarpa. All the isolates were evaluated for their antiproliferative activities against SMMC-7721, HL-60, SW480, MCF-7, and A-549 cell lines. Lyonicarposides A (1) and B (2) showed moderate antiproliferative activities against five cancer cell lines with IC50 values ranging from 12.39 to 28.71 µM. Lyonicarposides C (3) and G (7) and lyonifoloside M (12) selectively inhibited the proliferation of HL-60 and MCF-7 cell lines with IC50 values ranging from 13.03 to 17.71 µM. Interestingly, lyonifoloside L (13) selectively inhibited the proliferation of MCF-7 cell line with an IC50 value of 16.27 µM. Their structure-activity-relationships were discussed.

Recovery of phosphorus via harvesting phosphorus-accumulating granular sludge in sequencing batch airlift reactor.

A novel approach was developed for phosphorus recovery from wastewater through thermal treatment of matured phosphorus-accumulating granular sludge cultivated in sequencing batch airlift reactor (SBAR) system. Results showed that SBAR system had stable performances, in which COD, total phosphorus (TP) and total nitrogen (TN) removal efficiencies were stabilized at 80%, 89% and 86%, respectively. The matured granules were gathered from SBAR reactor and heated at relatively low temperature (100°C, 200°C, 300°C). The total P content in thermal treated granular sludge was more than half of total nutrient. Furthermore, the phosphorus release rate for treated granules was negatively correlated with thermal treatment temperature. These results demonstrated that the granules harvested from SBAR system followed with thermal pre-treatment could probably be applied as excellent slow-release phosphorus fertilizer. Hence, low temperature treatment of phosphate-accumulating granules is efficient for phosphorus recovery from wastewater, which is likely to promote the application of granulation technology.

Performance evaluation of a slow-release packing material-embedded functional microorganisms for biofiltration.

A composite packing material (CM-5) was prepared in this study, mainly consisting of compost with functional microorganisms, calcium carbonate (CaCO3), perlite, cement and plant fiber. To get stronger compressive strength, mass ratios of these components were optimized based on single factor experiments, and finally adding amounts of perlite, cement, plant fiber, CaCO3, compost and binder at 18%, 18%, 7%, 13%, 17% and 27%, respectively. According to the optimum proportion, CM-5 was extruded in cylindrical shape (12 mm in diameter and 20 mm in length) with a bulk density of 470 kg m-3, a moisture retention capacity of 49% and the microbial counts of × 105 CFU g-1 of packing material. The cumulative release rates of total organic carbon (TOC) and total nitrogen (TN) from CM-5 were 3.1% and 6.5%, respectively, after 19 times extraction in distilled water. To evaluate the H2S removal capacity, CM-5 was compared with an organic (corncob) and an inorganic (ceramsite) packing material in three biofilters. The results showed that CM-5 had higher H2S removal capacity compared with corncob and ceramsite. CM-5 could avoid the large fluctuation of pH value and pressure drop during the operation. The maximum H2S removal capacity of CM-5 was 12.9 g m-3 h-1 and the removal efficiency could maintain over 95.4% when the inlet H2S loading rate was lower than 11.3 g m-3 h-1 without any addition of nutrients and pH buffer substances. Besides, only 2-3 days were needed for the recovery of biofiltration performance after about two weeks of idle period.

Fluorescence complementation via EF-hand interactions.

Fluorescence complementation technology with fluorescent proteins is a powerful approach to investigate molecular recognition by monitoring fluorescence enhancement when non-fluorescent fragments of fluorescent proteins are fused with target proteins, resulting in a new fluorescent complex. Extension of the technology to calcium-dependent protein-protein interactions has, however, rarely been reported. Here, a linker containing trypsin cleavage sites was grafted onto enhanced green fluorescent protein (EGFP). Under physiological conditions, a modified fluorescent protein, EGFP-T1, was cleaved into two major fragments which continue to interact with each other, exhibiting strong optical and fluorescence signals. The larger fragment, comprised of amino acids 1-172, including the chromophore, retains only weak fluorescence. Strong green fluorescence was observed when plasmid DNA encoding complementary EGFP fragments fused to the EF-hand motifs of calbindin D9k (EF1 and EF2) were co-transfected into HeLa cells, suggesting that chromophore maturation and fluorescence complementation from EGFP fragments can be accomplished intracellularly by reassembly of EF-hand motifs, which have a strong tendency for dimerization. Moreover, an intracellular calcium increase upon addition of a calcium ionophore, ionomycin in living cells, results in an increase of fluorescence signal. This novel application of calcium-dependent fluorescence complementation has the potential to monitor protein-protein interactions triggered by calcium signalling pathways in living cells.