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The chlorophyll ethanol-extracted silkworm excrement was hardly biologically reused or fermented by most microorganisms. However, partial extremely environmental halophiles were reported to be able to utilize a variety of inexpensive carbon sources to accumulate polyhydroxyalkanoates. In this study, by using the nile red staining and gas chromatography assays, two endogenous haloarchaea strains: Haloarcula hispanica A85 and Natrinema altunense A112 of silkworm excrement were shown to accumulate poly(3-hydroxybutyrate) up to 0.23 g/L and 0.08 g/L, respectively, when using the silkworm excrement as the sole carbon source. The PHA production of two haloarchaea showed no significant decreases in the silkworm excrement medium without being sterilized compared to that of the sterilized medium. Meanwhile, the CFU experiments revealed that there were more than 60% target PHAs producing haloarchaea cells at the time of the highest PHAs production, and the addition of 0.5% glucose into the open fermentation medium can largely increase both the ratio of target haloarchaea cells (to nearly 100%) and the production of PHAs. In conclusion, our study demonstrated the feasibility of using endogenous haloarchaea to utilize waste silkworm excrement, effectively. The introduce of halophiles could provide a potential way for open fermentation to further lower the cost of the production of PHAs.

An efficient and regioselective C3-alkoxymethylation of indoles has been developed with aldehydes and alcohols via three-component cascade reaction under transition-metal free conditions. This method allows for rapid access to a variety of C3-alkoxymethylaed free (N-H) indole in up to 98% yield with excellent regioselectivity. The titled products are useful building blocks in organic synthesis.

A new dual chemosensor ( TTF-PBA ) for Fe 3+ and Cu 2+ in different signal pathways was designed and synthesized. The absorption spectrum, fluorescence spectrum and cyclic voltammograms changed in the presence of Cu 2+ and Fe 3+ . The optical color changed within 5 s from yellow to orange upon the addition of Cu 2+ , and it changed to dark yellow when Fe 3+ existed. The cyclic voltammogram of Cu 2+ /TTF-PBA changed from E ox = 0.50 V, E red = 0.32 V to E ox = 0.64 V, E red = 0.80 V ( vs Ag/AgCl) upon the addition of 2.0 equiv. Cu 2+ . As for Fe 3+ /TTF-PBA, its oxidation wave disappeared, and its reduction wave appeared at E red = −0.59 V ( vs Ag/AgCl) upon the addition of 4.0 equv. Fe 3+ . The sensor displayed high selectivity for Cu 2+ and Fe 3+ over other ions including Pb 2+ , Zn 2+ , Ni 2+ , Ag + , Cr 3+ , Mn 2+ , Al 3+ , Co 2+ , Pd 2+ , Hg 2+ , Fe 2+, Cd 2+ , Ce 3+ , Bi 3+ and Au 3+ , the detection limits for Cu 2+ and Fe 3+ ion reached as low as 5.33 × 10 −7 mol/L and 5.34 × 10 −7 mol/L, respectively. Furthermore, when Fe 3+ existed, Cu 2+ can be detected sequentially by the sensor through the absorption spectrum and the color change observed by naked-eyes.

A novel turn-off probe for copper(II) containing benzo[1,2-b:4,5-b′]dithiophene (BDT) and two picolinamide units was synthesized. In this probe, two picolinamide units complex with one Cu2+ ion and two nitrogen atoms in each picolinamide unit coordinate with Cu2+, which is verified by DFT calculation. Its fluorescence quantum yield is 0.43 and the detection limit is as low as 2.4×10−8 mol/L. The results show that the probe displays good selectivity for Cu2+ over other ions (Mn2+, Pb2+, Cr3+, Zn2+, Ni2+, K+, Ca2+, Ag+, Mg2+, Fe3+, Fe2+, Hg2+, Al3+, Cd2+, Pd2+, Co2+). Furthermore, the probe induced by Cu2+ and the π–π interaction of the aromatic unit can also form rod structure assembly, which can be observed by scanning electron microscopy (SEM).

This paper reports the self-assembly of two new tetrathiafulvalene (TTF) derivatives that contain one or two urethane groups. The formation of nanoribbons was evidenced by scanning electron microscopy (SEM) and X-ray diffraction (XRD), which showed that the self-assembly ability of T1 was better than that of T2. The results revealed that more urethane groups in a molecule did not necessarily instigate self-assembly. UV–vis and FTIR spectra were measured to explore noncovalent interactions. The driving forces for self-assembly of TTF derivatives were mainly hydrogen bond interactions and π–π stacking interactions. The electronic conductivity of the T1 and T2 films was tested by a four-probe method.

Two novel donor-π-acceptor chemosensors, exTTF-DPA and exTTF-ADPA, based on π-extended tetrathiafulvalene (exTTF) and di(pyridine-2-ylmethyl)amine (DPA) were synthesized and used as optical and electrochemical chemosensors for copper(II). The results showed that they possess specific selectivity for copper(II) in the presence of other competing metal ions (Zn2+, Sn2+, Pb2+, Pd2+, Hg2+, Al3+, Fe3+, Ag+, Co2+, Ni2+) in acetonitrile. Upon the addition of Cu2+, the solution color changed from yellow to orange, the cyclic voltammograms changed dramatically and the fluorescence quenched completely.

A series of new A–π–D–π–A molecules including diphenylamine and carbazole had been synthesized and characterized ( T1 – T3 ). T1 and T2 displayed aggregation-induced emission enhancement (AIEE): exhibiting weak fluorescence in pure THF, which a signification AIEE effect was observed in mixture with a water fraction ( f w ) of 90% with a sharp increase in fluorescence intensity. T3 displayed aggregation-caused quenching (ACQ): exhibiting strong fluorescence in pure THF, which a signification ACQ effect was observed in mixture with a water fraction ( f w ) of 90% with a sharp decrease in fluorescence intensity. Their two-photon absorption (2PA) had been investigated using the open-aperture Z-scan technique, and the values of the 2PA cross section at 800 nm for T1 – T3 were 1115, 681, in chloroform, respectively.

A novel and efficient oxidation of salicyl alcohols to the corresponding salicylaldehydes catalyzed by lipase is reported for the first time. Under the optimal reaction conditions, the method exhibited high yields (81–95%) and selectivities for salicylaldehydes. Moreover, this study expands the application of enzyme catalytic promiscuity in organic synthesis.