Antimicrobial and Cytotoxic Secondary Metabolites from a Marine-Derived Fungus Penicillium Citrinum VM6.

Investigation of an antimicrobial and cytotoxic ethyl acetate extract prepared from solid fermentation of the marine-derived fungus Penicillium citrinum VM6 led to the isolation of eight metabolites (1-8), including one citrinin dimer dicitrinone F (1). Of these, compound 7 was isolated for the first time from the Penicillium genus and compound 1 with carbon-bridged C-7/C-7' linkage is rarely reported. All compounds (1-8) exhibited selective antimicrobial activity against the tested Gram-positive bacteria and Candida albicans with MICs of 32-256 µg/mL. Compounds 1 and 8 exhibited cytotoxicity against all tested cell lines A549, MCF7, MDA-MB-231, Hela, and AGS with IC50 values of 6.7 ± 0.2 to 29.6 ± 2.2 µg/mL, whereas compound 5 had selective cytotoxicity against the MCF7 cell lines with IC50 of 98.1 ± 7.8 µg/mL.

A Pair of Undescribed Alkaloid Enantiomers from Marine Sponge-Derived Fungus Hamigera avellanea and Their Antimicrobial and Cytotoxic Activities.

From marine sponge-associated fungus Hamigera avellanea, thirteen secondary metabolites including a pair of undescribed alkaloid enantiomers (+)-hamiavemin A (4S) (+)-1 and (-)-hamiavemin A (4R) (-)-1. Compound 1 was enantiomers resolved by the Chiralpak AS-3 column, using a hexane/isopropanol mobile phase. Their structures were determined based on extensive analyses of HR-ESI-MS, 1D and 2D NMR spectra. The absolute configuration of (+)-1 and (-)-1 were assigned tentatively by ECD calculations. Among the isolates, compound 6 showed strongest antibacterial activity against Enterococcus faecalis, Staphylococcus aureus, Bacillus cereus, Escherichia coli, Salmonella enterica, and Candida albicans with the MIC values of 2, 2, 16, 32, 64, and 16 µg/mL, respectively, which were stronger than that of the positive control compound, kanamycin (MIC values ranging from 4 to 128 µg/mL). In addition, compounds 1, 2, and 9 showed moderate cytotoxic activity against three cancer cell lines, HepG2, A549, and MCF-7 with the IC50 values ranging from 55.35±1.70 to 83.02±2.85 µg/mL.

Stable water-floating transistor with recyclability.

Electronic wastes from used devices containing environmentally hazardous materials are an immediate concern for the sustainable development of electronic and sensor industries. To address this, a highly controllable and dedicated electronic module should be devised, that allows systematic recollection of as many components from the original device for their reuse. Here, we report the total recycling of an electronic device, exploiting a water-floating system that is based on a water-compatible semiconductor as an active material. To do so, we developed a system for stable electronics on the water surface. The floating semiconductor features a tunable morphology on the water surface, and is constructed into a water-floating gated transistor (WFGT) and water floating sensor (WFS), exhibiting an on-current of 4.2 × 10-5 A and an on/off ratio of ∼103. The device showed high recyclability over 25 cycles, with an efficiency of 99 ± 0.9% within 1 cycle and 92 ± 0.7% within 30 cycles. Furthermore, the device was also found to be stable for over 10 days. Our system has the potential to be an eco-friendly, cost-effective, and scalable device that is fully recyclable, which can be applied in areas once thought of as being beyond the scope of current semiconductor technology.

Biosorbent derived from coffee husk for efficient removal of toxic heavy metals from wastewater.

In this study, we investigated the feasibility on the utilization of coffee husk as biosorbents for the removal of heavy metal ions such as Pb2+ and Cd2+ from wastewater. Biochar was produced from coffee wastes and modified with sodium hydroxide to create functional groups on the surface and increase the specificic surface area. The resultant products were characterized by using various analytical methods such as scanning electron microscopy, specific area, surface functional group and zeta potential analysis. The as-prepared materials were employed as adsorbent to remove Pb2+ and Cd2+ ions from wastewater. The maximum sorption capacities of biosorbents were measured to be 116.3 and 139.5 mg g-1 for Cd2+ and Pb2+, respectively, which is comparable to the conventional adsorbents. Kinetic studies showed that the sorption of Pb2+ and Cd2+ on biosorbents can be described by the Freundlich isotherm and second-order kinetic model. The coffee husk-derived biosorbent was capable of removing 89.6% of Pb2+ and 81.5% Cd2+ ions from wastewater, and therefore can be considered as low-cost and efficient adsorbent to remove heavy metal ions from wastewater.

Enhanced recovery of phosphate as a value-added product from wastewater by using lanthanum modified carbon-fiber.

The aim of this study is to present the potential of activated carbon fiber (CF) impregnated with lanthanum (La) as a novel adsorbent (La-CF) of phosphate-phosphorus (P) and to assess the value-added due to P-recovery from wastewater using La-CF. The CF were loaded with La and the loaded CF was then calcined at 500 °C. The La-CF adsorbent was used in a series of batch experiments to characterize the adsorption of P at pH of 6-10 and P concentrations of 1-200 mg/L. Physical-chemical properties such as surface morphology, surface charge, surface area, and surface chemistry were determined for the La-CF. The La-CF exhibited adsorption capacity of 196.5 mg/g, fast sorption kinetics and high selectivity for P removal from aqueous solution. La-CF removed 97.3% of P from wastewater and achieved P-level to below 2 mg/L. It was repetitively reused over 10 times in successive cycles to remove P from wastewater. The value-added by recovery of P from wastewater was calculated at around 0.12 US$/L, demonstrating economic benefits of La-CF. In conclusion, the successful removal, recycling, and recovery value-added of P using La-CF adsorbent displayed good potential for developing the technology for treatment of wastewaters to recover valuable compounds such as phosphorus.