High Pressure Processing Impact on Alternariol and Aflatoxins of Grape Juice and Fruit Juice-Milk Based Beverages

High-pressure processing (HPP) has emerged over the last 2 decades as a good alternative to traditional thermal treatment for food safety and shelf-life extension, supplying foods with similar characteristics to those of fresh products. Currently, HPP has also been proposed as a useful tool to reduce food contaminants, such as pesticides and mycotoxins. The aim of the present study is to explore the effect of HPP technology at 600 MPa during 5 min at room temperature on alternariol (AOH) and aflatoxin B1 (AFB1) mycotoxins reduction in different juice models. The effect of HPP has also been compared with a thermal treatment performed at 90 °C during 21 s. For this, different juice models, orange juice/milk beverage, strawberry juice/milk beverage and grape juice, were prepared and spiked individually with AOH and AFB1 at a concentration of 100 µg/L. After HPP and thermal treatments, mycotoxins were extracted from treated samples and controls by dispersive liquid–liquid microextraction (DLLME) and determined by HPLC-MS/MS-IT. The results obtained revealed reduction percentages up to 24% for AFB1 and 37% for AOH. Comparing between different juice models, significant differences were observed for AFB1 residues in orange juice/milk versus strawberry juice/milk beverages after HPP treatment. Moreover, HPP resulted as more effective than thermal treatment, being an effective tool to incorporate to food industry in order to reach mycotoxins reductions.     

Thermal analysis, Raman spectroscopy and complex impedance analysis of Cu2+-doped KDP

Raman spectroscopy and differential thermal analysis (DTA) and thermogravimetric analysis have been carried out on Cu-doped KH₂PO₄ (Cu-KDP). X-ray diffraction powder data reveal that the structure of the KDP crystal does not change with the additive Cu²⁺ ion. DTA analysis and Raman study of Cu-KDP as a function of temperature reveal that this compound undergoes two phase transitions at about Ttr =453 and 473 K. The electrical conductivity measurements on polycrystalline pellet of Cu-KDP (5) are performed from room temperature (RT) up to 495 K. Only one phase transition is observed at 470 K. The activation energy in the migration is 0.42 eV in the temperature range from RT to 470 K. For temperature above 470 K, the activation energy of the superprotonic phase is 1.87 eV.     

Synthesis,crystal structure and dielectric properties of C6H18N2SbCl5

The result of the X‐ray diffraction, differential scanning calorimetry and dielectric studies on a new crystal material C₆H₁₈N₂SbCl₅ is presented. The new organic–inorganic compound has been synthesized and characterized by the X‐ray diffraction method at 296(2) K. It crystallizes in the monoclinic P21/n space group. The cell dimensions are: a = 5.8617(1) Å, b = 15.7069(2) Å, c = 16.6693(2) Å, β = 97.627(1)° and Z = 4. The crystal structure consists of a discrete ionic layer of (C₆H₁₈N₂)²⁺ cations and [SbCl₅]^2? anions linked via simple and bifurcated N―H · · · Cl hydrogen bonds. DSC analysis shows that this compound undergoes a phase transition at about (384 ± 2) K. AC and DC conductivities, complex dielectric permittivity ε*(ω) and complex electrical modulus M*(ω) were respectively studied as temperature and frequency functions. The combined data support each other and confirm the existence of a structural phase transition at about 384 K. Moreover, the temperature dependence of the DC conductivity and relaxation frequency followed the Arrhenius relation. The frequency dependence of the real part of the AC conductivity in both phases follows the Jonscher's universal dynamic law: . The behavior of s(T) with temperature suggests that the hopping over barrier model (CBH) and the small polaron tunneling mechanism (SPTM) prevail in phases I and II, respectively. Copyright © 2016 John Wiley & Sons, Ltd.     

褐铁矿处理水中六价铬

Cr(VI)是土壤和水体中常见的有毒污染物,将Cr(VI)转化为毒性较低的Cr(III)是常用而有效的治理方法.本文采用褐铁矿对水中Cr(VI)进行处理研究,考察了褐铁矿投加量、Cr(VI)初始浓度、pH值、反应温度、铁矿石粒径大小以及添加不同物质等因素对褐铁矿去除效果的影响.结果表明,褐铁矿对Cr(VI)有很好的还原去除效果,Cr(VI)去除效率随褐铁矿用量的增加而增大,随Cr(VI)初始浓度的增加而减小,pH值越低越有利于反应的进行.铁矿石颗粒的直径越小,比表面积越大,也对反应越有利,而温度对Cr(VI)的去除影响不大.100目的褐铁矿颗粒去除Cr(VI)的能力为7.77 mg Cr(VI)/g.使用褐铁矿不仅可以将Cr(VI)还原为Cr(III),还能将Cr(VI)彻底从水中去除.     

In vitro cytotoxic and antiviral activities of Ficus carica latex extracts

The latex of fig fruit (Ficus carica) is used in traditional medicine for the treatment of skin infections such as warts and also diseases of possible viral origin. Five extracts (methanolic, hexanic, ethyl acetate, hexane-ethyl acetate (v/v) and chloroformic) of this species were investigated in?vitro for their antiviral potential activity against herpes simplex type 1 (HSV-1), echovirus type 11 (ECV-11) and adenovirus (ADV). To evaluate the capacity of the extracts to inhibit the replication of viruses, the following assays were performed: adsorption and penetration, intracellular inhibition and virucidal activity. Observation of cytopathic effects was used to determine the antiviral action. The hexanic and hexane-ethyl acetate (v/v) extracts inhibited multiplication of viruses by tested techniques at concentrations of 78 μg mL(-1). These two extracts were possible candidates as herbal medicines for herpes virus, echovirus and adenovirus infectious diseases. All extracts had no cytotoxic effect on Vero cells at all tested concentrations.     

Clay-Catalyzed Ozonation of Hydrotalcite-Extracted Lactic Acid Potential Application for Preventing Milk Fermentation Inhibition

An unprecedented route for mitigating the inhibitory effect of lactic acid (LA) on milk fermentation was achieved through lactate adsorption on hydrotalcite (Ht) from simulated lactate extracts. During its regeneration by ozonation, Ht displayed catalytic activity that appeared to increase by addition of montmorillonite (Mt). Changes in the pH, Zeta potential and catalyst particle size during LA ozonation were found to strongly influence LA–LA, LA–catalyst and catalyst–catalyst interactions. The latter determine lactate protonation–deprotonation and clay dispersion in aqueous media. The activity of Mt appears to involve hydrophobic adsorption of non-dissociated LA molecules on silica-rich areas at low pH, and Lewis acid–base and electrostatic interactions at higher pH than the pKa. Hydrotalcite promotes both hydrophobic interaction and anion exchange. Hydrotalcite–smectite mixture was found to enhance clay dispersion and catalytic activity. This research allowed demonstrating that natural clay minerals can act both as adsorbents for LA extract from fermentation broths and as catalysts for adsorbent regeneration. The results obtained herein provide valuable and useful findings for envisaging seed-free milk clotting in dairy technologies.     

石化装置工业尺度管道爆轰传播实验研究

针对石化装置罐区大口径、长距离管道内火焰传播缺乏系统研究的问题,设计搭建了DN50～DN500工业尺度管道火焰传播实验装置,并开展了丙烷/空气、乙烯/空气等可燃气体在不同管径下的实验研究。实验结果表明:可燃气体积分数对火焰传播及爆轰有一定影响,当接近化学计量浓度时,爆轰加速距离更短,更易形成稳态爆轰,而当可燃气混合气为贫燃或富燃状况时,爆轰加速距离则会增长;火焰爆轰传播速度、爆轰压力与管道管径基本无关,受可燃气种类影响更大;对应体积分数为6.6%的乙烯/空气和体积分数为4.2%的丙烷/空气混合气体,爆轰压力分别是初始压力的15.17和14.47倍,DN150以下管径内的爆轰压力远高于ISO16852标准给出的参考值。罐区连通管道阻火器选型安装时,应结合安装位置选用合适的阻火器。