Isolation of Penicillium citrinum from Roots of Clerodendron cyrtophyllum and Application in Biosynthesis of Aglycone Isoflavones from Soybean Waste Fermentation.

Soybeans offer an abundant source of isoflavones, which confer useful bioactivities when existing in aglycone forms. The conversion of isoflavones into aglycones via fermentation of soybean products is often realized by ß-glucosidase, an enzyme produced by fungi. In this study, a filamentous fungus, Clerodendron cyrtophyllum, was isolated from root of Clerodendron cyrtophyllum Turcz, which was able to produce the highest activity of ß-glucosidase up to 33.72 U/mL at 144 h during fermentation on Potato Dextrose Broth (PDB). The obtained fungus was grown on isoflavones-rich soybean extract to produce genistein and daidzein, achieving the conversion rate of 98.7%. Genistein and daidzein were isolated and purified by column chromatography using hexane/acetone (29:1/1:1), reaching purities of over 90% of total isoflavones, as identified and determined by TLC, LC-MS/MS, and 1H and 13C NMR spectroscopy. These results imply that the isolated P. citrinum is a potential fungal strain for industrial-scale production of genistein and daidzein from isoflavones-containing soybean extracts. These products may serve as potential raw materials for manufacture of functional foods that are based on aglycones.

Multiresidue Pesticides Analysis of Vegetables in Vietnam by Ultrahigh-Performance Liquid Chromatography in Combination with High-Resolution Mass Spectrometry (UPLC-Orbitrap MS).

An ultrahigh-performance liquid chromatography in combination with high-resolution mass spectrometry Thermo Q-Extractive Focus Orbitrap MS has been introduced for analysis of multiclass pesticides in vegetable samples collected in Hanoi, Vietnam. Multiclass pesticides were separated on the Thermo Hypersil Gold PFP column utilizing a gradient of the mobile phase consisting of 5 mM ammonium formate, 0.1% formic acid in deionized water, and methanol. The target analytes were detected in the full-scan mode on Thermo Scientific Q-Exactive Focus Orbitrap MS for quantitation at the optimum operating conditions. These conditions included, but not limit to, the resolution of 70000 at the full width at half maximum in both positive and negative mode, mass range from 80 to 1000 m/z, and optimized parameters for the heated electrospray ionization source. The identification of the analytes in real samples was based on retention times, mass to charge ratios, mass accuracies, and MS/MS spectra at the confirmation mode with the inclusion list of target analytes. The mass accuracies of target analytes were from -4.14 ppm (dinotefuran) to 1.42 ppm (cinosulfuron) in the neat solvent and from -3.91 ppm (spinosad D) to 1.29 ppm (cinosulfuron) in the matrix-matched solution. Target analytes in the vegetable-based matrix were extracted by the QuEChERS method. Some critical parameters of the analytical method such as linearity, repeatability, limit of detection, and limit of quantitation have been evaluated and implemented. Excellent LOD and LOQ of the developed method were achieved at the range of 0.04-0.85 and 0.13-2.9 µg·kg-1, respectively. Intraday and interday repeatability of the analytical signal (peak area, n=6) of the developed method were below 3% and 10%, correspondingly. The matrix effect, extraction recovery, and overall recovery were fully investigated by spiking experiments. Experimental results demonstrated that the ionization suppression or enhancement was the main contribution on the overall recoveries of target analytes. Finally, the in-house validated method was applied to pesticides screening in vegetables samples in local villages in Hanoi, Vietnam. The concentrations of all target analytes were below limit of quantitation and lower than US-FDA or EU maximum residue levels.

Synthesis and cytotoxic evaluation of novel ester-triazole-linked triterpenoid-AZT conjugates.

Betulinic acid and analogous naturally occurring triterpenoid acids were transformed into the corresponding propargyl esters and subsequently deployed as substrates for a click chemistry-mediated coupling with azidothymidine (AZT) en route to novel 1,2,3-triazole-tethered triterpenoid-AZT conjugates. Twelve new hybrids were thus prepared and assessed in terms of their cytotoxic activity, revealing an interesting anticancer activity of five triterpenoid-AZT hybrids on KB and Hep-G2 tumor cell lines.

Synthesis of new bioisosteric hemiasterlin analogues with extremely high cytotoxicity.

In this Letter, the synthesis and the evaluation of the cytotoxicity of new hemiasterlin analogues were reported. The indole moiety was replaced respectively by benzofurane, naphthalene and 4-bromobenzene groups. Most of these derivatives possess strong cytotoxic activity on two human tumour cell lines (KB and Hep-G2), and some analogues showed comparable cytotoxic activity to that observed for paclitaxel and ellipticine, against KB and Hep-G2 cancer cell lines.

Synthesis of new simplified hemiasterlin derivatives with α,ß-unsaturated carbonyl moiety.

In this Letter, we report a convenient and efficient method for the synthesis of new simplified derivatives of hemiasterlin in which the α,α-dimethylbenzylic moiety A is replaced by α,ß-unsaturated aryl groups as Michael acceptor. Most of these derivatives have a strong cytotoxic activity on three human tumor cell lines (KB, Hep-G2 and MCF7). Analogs 17b and 17f showed a high cytotoxicity against KB and Hep-G2 cancer cell lines comparable to paclitaxel and ellipticine.