Applicability assessment of a real-time PCR assay for the specific detection of bovine,ovine and caprine material in feedstuffs

A TaqMan real-time polymerase chain reaction (PCR) method was developed for specific detection of bovine, ovine and caprine processed animal protein (PAP) in industrial feedstuffs. The method uses species-specific primers and probes targeting short mitochondrial D-loop sequences, and a positive amplification control based on 18S rRNA gene. The applicability of the real-time PCR protocol was assessed through analysis of 126 industrial feed samples that were manufactured to reproduce rendering processes of commercial feeds destined for farmed animals. The assay successfully classified samples as positive or negative according to the ruminant composition, enabling qualitative detection of banned material in feeds at levels as low as 0.1%. Although the method provides quantitative potential, results suggest that the real quantitative capability of the assay is limited by the existing variability in terms of composition and processing treatments of the feeds, which affect the amount and quality of amplifiable DNA.     

Alumina supported copper nanoparticles for aziridination and cyclopropanation reactions

Alumina supported copper (Cu–Al₂O₃) nanoparticles were prepared and applied for the aziridination of olefins employing [N-(p-tolylsulfonyl)imino]phenyliodinane (PhI = NTs) as nitrene source to afford the corresponding 3-membered cyclic compounds in moderate to excellent yields. Cyclopropanation of several olefins was also carried out by using Cu–Al₂O₃ nanoparticles and ethyl diazoacetate as a carbene source. The catalyst was recovered by simple centrifugation and reused for four cycles.     

A facile hydrothermal synthesis of visible-light responsive BiFeWO6/MoS2 composite as superior photocatalyst for degradation of organic pollutants

In the present study, we have fabricated a new Z-scheme BiFeWO₆/MoS₂ composite for photocatalytic elimination of organic contaminants from the waste-water. A series of BiFeWO₆/MoS₂ composites were obtained by changing the amounts of BiFeWO₆ from 1 to 10 mg through a facile hydrothermal method. The phase structures and morphologies of these BiFeWO₆/MoS₂ composites were analyzed by SEM, HR-TEM, XRD, UV–vis DRS, element mapping and XPS techniques. Afterward, the dye-degradation experiments were conducted for the removal of Rhodamine B (RhB) using as-obtained BiFeWO₆/MoS₂ composite samples under visible-light illumination to evaluate their photocatalytic activity. It is found that the BiFeWO₆/MoS₂ composites exhibited great photocatalytic behavior than the pure BiFeWO₆ and MoS₂ samples. In particular, the BiFeWO₆/MoS₂ composite with 5 mg of BiFeWO₆ showed a quickly complete photocatalyst degradation ability of RhB in 75 min with high photo-stability and reusability behavior. This superior catalytic response of BiFeWO₆/MoS₂ composite may be contributed by its high light harvesting capacity as well as fast separation and movement of photo-generated electron-hole pairs. This proposed BiFeWO₆/MoS₂ composite is a very promising photocatalyst for environmental remediation work.     

Preparation of nanocrystalline tin powders by the γ-radiation method

The γ-radiation method has been successfully used to prepare nanocrystalline tin powders. X-ray powder diffraction reveals that the product is single phase of tin with a tetragonal structure. Electron microscopy shows that the average particle size is about 28 nm. The mechanism of Sn²⁺ ion reduction during γ-irradiation is discussed.     

An immunoassay for ochratoxin A without the mycotoxin

Phage display peptide libraries allow the selection of new molecules capable of mimicking the structural and functional features of native proteins or chemicals. This technology can be applied to developing new reagents, which may serve as the surrogate of the original objects. In order to screen peptides capable of mimicking ochratoxin A (OTA) in the interaction with anti-OTA monoclonal antibody (McAb) and establish the immunoassay for OTA, an anti-OTA McAb was used as the target for panning-elution selection from a phage random seven-peptide library. After four rounds of panning, 11 phages were found to be able to mimic OTA in binding with the antibody. Enzyme-linked Immunosorbent Assay (ELISA) for detecting OTA was established with the phages. In the most sensitive assay, the linear range of the inhibition curve was 200–8000 pg/ml; the detection limit was 150 pg/ml. The inserted peptide sequences were deduced by DNA sequencing. The common amino acid residue sequence was IR(V)PMV(L)XX (X is any amino acid residues), which was verified by two synthesized peptides. The results demonstrated that those phage peptides could be used as the surrogate of OTA to establish the immunoassay.     

HPLC–MS validation of QualisaFoo® biosensor kit for cost-effective control of acrylamide levels in Italian coffee

Acrylamide is a carcinogenic and mutagenic compound found in many industrially processed foods and beverages, including coffee. The aim of this work is to determine the acrylamide level in some Italian coffees by using a mass spectrometry method and an enzymatic test kit. Comparison of average values in four Italian coffees determined using the two methods permitted us to validate the results obtained with the kit, hence the kit itself, showing that acrylamide is present in low amount.The amount of acrylamide was also determined in other foods, by using the kit. This work shows that there is a correspondence between the two methods and that the kit provides a cost-effective method to determine the amount of acrylamide in food.     

The production of hypocrellin colorants by submerged cultivation of the medicinal fungus Shiraia bambusicola

Hypocrellin production using submerged cultivation of the medicinal fungus Shiraia bambusicola revealed that both glucose and (NH₄)₂SO₄ were optimal carbon and nitrogen sources. Hypocrellin production increased with increasing initial glucose concentration within the range of 10–50 g l^?1 and (NH₄)₂SO₄ concentration in the range of 1–2 g l^?1. The effects of carbon and nitrogen concentration were optimized using central composite experimental design and response surface analysis; maximum hypocrellin production (196.94 ± 6.93 mg l^?1) was achieved using 45.7 g l^?1 glucose and 1.93 g l^?1 (NH₄)₂SO₄.     

Tumor extracellular matrix-targeted nanoscavengers reverse suppressive microenvironment for cocktail therapy

Extracellular matrix (ECM) is not only a natural bulwark to shield solid tumor cells from therapeutic agents and cytotoxic T lymphocytes (CTLs), but also one of the key factors that cause tumor hypoxic environment, severely hindering photodynamic reactions and immune responses. In this work, multifunctional nanoscavengers (ECMT NS) consisting of digestive enzyme chymotrypsin, catalase, calcium peroxide nanoparticles, photosensitizer chlorin e6, and tumor ECM-targeting CLT1 peptide are rationally designed with several benefits for enhanced cocktail calcium ion/photodynamic/immune therapy. The scavengers can effectively “clear” tumor ECM via digestive proteolytic enzyme- and reactive oxygen species-mediated pathways, deepening tumor penetration of the scavengers and CTLs. Thanks to the ECM destruction and oxygen self-supply capability of ECMT NS, the hypoxia in tumors is attenuated, thus improving photodynamic therapeutic efficiency and downregulating immunosuppressive factors. Moreover, the combination of calcium ion overload and photodynamic therapy enriches damage-associated molecular patterns, which promotes CTL activation to inhibit abscopal tumor growth and lung metastasis. The presented ECM destruction strategy provides a solution to overcome the tumor suppressive microenvironment.