树莓果渣总花色苷和总多酚微波萃取工艺

采用响应面法中Box-Behnken设计对树莓果渣中总花色苷和总多酚微波辅助萃取工艺进行优化，并结合液相色谱-质谱联用技术对树莓果渣中花色苷组分进行鉴定，通过SEM观察经微波萃取和常规溶剂萃取后样品的微观结构。结果表明，微波辅助萃取树莓果渣中总花色苷和总多酚的最佳工艺参数为：萃取温度61 ℃、液料比30:1 mL/g和萃取时间5 min，在此条件下，树莓果渣总花色苷和总多酚含量分别为4.20 mg C3G/g和16.05 mg GAE/g。经微波萃取后样品细胞结构遭到严重破坏，而经传统的溶剂萃取后样品细胞结构保存完好，且微波法所得的树莓果渣总花色苷和总多酚含量明显较高。经鉴定树莓果渣中含有6种花色苷组分，分别为飞燕草素-3-葡萄糖苷、矢车菊素-3-芸香糖苷、牵牛花素-3-葡萄糖苷、芍药素-3.5-二己糖苷、芍药素-3-(6-丙二酰)-葡萄糖苷和天竺葵素-3-(6-丙二酰)-葡萄糖苷。     

Preparation and property of raspberry‐like AS/SiO2 nanocomposite particles

Surfactant‐free poly(acrylonitrile‐co‐styrene)/silica (AS/SiO₂) nanocomposite particles was synthesized in the presence of cheap, commercially amorphous aqueous silica sol at ambient temperature. Thermogravimetric analysis (TGA) indicated silica contents ranging from 5 wt % to 29 wt %, depending on reaction conditions. Particle size distributions and morphologies were studied using dynamic light scattering (DLS) and transmission electron microscopy (TEM), which clearly showed that most of the colloidal nanocomposites comprised approximately spherical particle with raspberry‐like morphology and relatively narrow size distributions. The optical clarity of solution‐cast nanocomposite films was assessed using UV–vis spectrometer, with high transmission being obtained over the whole visible spectrum. Differential scanning calorimetry (DSC) studies showed that the glass transition temperature of AS/SiO₂ nanocomposites can be higher than the corresponding pure AS, resulting from the hydrophilicity of the nanometer silica. The robustness and simplicity of this method may make large‐scale manufacture of this nanocomposite possible. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 415–421, 2007     

Dietary Black Raspberry Seed Oil Ameliorates Inflammatory Activities in db/db Mice

The objective of this study was to evaluate the status of the markers related to inflammation in db/db mice fed black raspberry seed (BRS) oil, which is rich in α‐linolenic acid. Mice were divided into four groups: (1) C57BL/6 mice fed 16 % calories from soybean oil (normal CON); (2) C57BL/KsJ‐db/db mice fed 16 % calories from soybean oil (CON); (3) C57BL/KsJ‐db/db mice fed 8 % calories from soybean and 8 % calories from BRS oil (BRS 50 %); and (4) C57BL/KsJ‐db/db mice fed 16 % calories from BRS oil (BRS 100 %). After 10 weeks, n‐6/n‐3 fatty acid ratios were significantly (P < 0.05) lower in the livers and epididymal adipose tissues of the BRS 50 % and BRS 100 % mice than in the CON. Serum TNFα and IL‐6 were significantly (P < 0.05) lower in the BRS 50 % and BRS 100 % than in the CON. Serum IL‐10 was significantly (P < 0.05) higher in the BRS 100 % than the CON. In the liver and epididymal adipose tissue, mRNA levels of pro‐inflammatory markers in the BRS 50 % and BRS 100 % were lower than in the CON. Anti‐inflammatory markers were higher in the epididymal adipose tissues of the BRS 50 % and BRS 100 % than in the CON. In the epididymal adipose tissue, macrophage infiltration markers (F4/80 and CD68) and leptin mRNA were significantly (P < 0.05) lower in the BRS 50 % and BRS 100 % than in the CON. Results of this study suggest that BRS oil may have anti‐inflammatory effects in obese diabetic mice by ameliorating inflammatory responses.     

喀什树莓酒及其5种伪品的红外指纹图谱鉴别

采用红外光谱法建立喀什树莓酒的指纹图谱,对主要吸收峰进行指认,并通过相似度分析和聚类分析法对10批树莓酒及5种伪品的红外图谱一致性进行考察。结果显示:10批树莓酒的红外指纹图谱具有很好的一致性,而且树莓酒及伪品通过相似度分析和聚类分析均能够很好地区分开来,两种化学计量方法具有良好的相关性。说明本方法简便可靠,是一种对树莓酒进行质量评价的好方法。     

华中地区不同品种树莓果实成熟过程中特征活性物质的变化

以华中地区四种不同成熟阶段的树莓果实为研究对象,采用分光光度法测定其总酚含量、总花色苷含量和超氧化物歧化酶活性;采用超高效液相色谱-串联质谱仪鉴定其酚类物质,并用液相色谱仪对其绝对含量进行定量。研究结果表明,随着树莓果实的成熟,四种树莓果实中总酚的含量均呈下降趋势,与此同时,其总花色苷的含量均呈上升趋势。美22树莓果实的总酚含量（31.94 mg/g FW）和总花色苷含量（1.31 mg/g FW）均是四种树莓果实中最高的。四种树莓果实中共鉴定出9种酚类物质,5种花色苷类酚类物质和4种非花色苷类酚类物质,矢车菊素3-O-槐糖苷和矢车菊素3-O-葡萄糖苷为主要的花色苷类酚类物质;Lambertianin C和地榆素H-6为主要的非花色苷类酚类物质。此外,四种树莓果实中超氧化物歧化酶的活性呈下降趋势,其中天门三号树莓果实超氧化物歧化酶活性降低最多（37%）。该研究为华中地区树莓果实的开发利用提供基础数据。     

Preparation of nano‐sized silica/poly(methyl methacrylate) composite latexes by heterocoagulation: comparison of three synthetic routes

Continuing earlier work, 2,2′‐azobis(isobutyramidine) dihydrochloride (AIBA) was used as a cationic initiator to generate positively charged polymers, and promote interaction of these polymers with the negatively charged surface of colloidal silica particles in aqueous solution. Three different synthetic routes have been investigated. In a first route, emulsion polymerization of MMA, initiated by AIBA, was performed directly in an aqueous suspension of the silica beads using a non‐ionic polyoxyethylenic surfactant (NP₃₀). In a second route, AIBA was first adsorbed on the silica surface, and the free amount of initiator was discarded from the suspension. The silica‐adsorbed AIBA adduct was suspended in water with the help of surfactant, and used to initiate the emulsion polymerization of MMA. In a third route, cationic PMMA particles were synthesized separately and subsequently adsorbed on the silica surface. Whatever the approach used for their elaboration, the colloidal nanocomposites were shown to exhibit a raspberry‐like morphology. Quantitative determination of the amount of surface polymer enabled us to evaluate the efficiency of the heterocoagulation process and establish a comparison among the three synthetic routes. Copyright © 2004 Society of Chemical Industry     

Retention Rate Enhancement of Antioxidant and Cyaniding 3-O-Glucoside Components of the Reconstituted Product from Spray-Dried Black Raspberry Juice by Optimizing Process Parameters

The effects of four operating parameters involved in the spray-drying process, including air inlet temperature (120–150°C), air flow rate (3.5–5.0 m³/h), feed flow rate (2–10 mL/min), and aspirator rate (50–70 m³/h), to produce black raspberry juice powders with the highest retention rate of healthy functional components were optimized using a response surface design. Second-order polynomial models with high R ² (0.955–0.972) values were developed using multiple linear regression analysis. Results showed that the most significant (p < 0.05) process conditions that affected the antioxidant activity and cyanidin-3-O-glucoside content (C3GLU) of powders respectively were the quadratic effects of air inlet temperature and air flow rate and quadratic terms of air and feed flow rates. Laser diffraction particle size analysis and scanning electron microscopy were used to relate the microstructure and quality features. The lowest EC₅₀ (0.0060 mL juice/g 1,1-diphenyl-2-picrylhydrazyl [DPPH]) and the highest C3GLU (4.721 mg/100 mL) values were achieved at an inlet temperature of 120.0°C, air flow rate of 4.20 m³/h, feed flow rate of 8.65 mL/min, and aspirator rate of 55.87 m³/h.     

基于树莓派的物联网开放平台

针对当前物联网所面对的共性需求,提出了建立开放性的物联网服务平台,为物联网世界提供开放的服务。完成了对传感器数据的接入、管理、存储、处理及应用。并以树莓派作为网关设备端进行图像数据的采集,通过Http或Socket.IO与云平台服务器建立连接,完成数据的实时传输。     

Fine‐Tuning of Superhydrophobicity Based on Monolayers of Well‐defined Raspberry Nanoparticles with Variable Dual‐roughness Size and Ratio

Superhydrophobic surfaces have been extensively investigated for self‐cleaning, low‐adhesion, anti‐corrosion or reduced‐drag applications. Roughness and its characteristics, i.e., morphology, overall roughness and individual feature size, is an essential factor for superhydrophobicity. Several experimental methods and theoretical models strived to predict how the surface wettability is affected by the surface roughness. However, due to the difficulty of making practical surfaces with well‐defined roughness profiles, only limited and arbitrary experimental studies focused on practical superhydrophobic films. Here, the roughness factors which determine the wetting properties of films are reported, based on monolayers of well‐defined raspberry silica‐silica nanoparticles, exhibiting a wide‐range and systematic variation of individual features sizes and ratios (large over small features). The advancing water contact angle does not depend on the feature size or ratio, while the contact angle hysteresis (CAH) is strongly dependent on both. The minimum size and size ratio to reach superhydrophobicity were determined. These new insights into the wetting of rough surfaces can be used to direct the design of practical superhydrophobic materials for advanced applications such as solar panels, microelectronics or microfluidic devices.     

Effect of hexanal vapor on the growth of postharvest pathogens and fruit decay

ABSTRACT:  The effect of the natural volatile hexanal was studied as an antifungal agent on the major postharvest fungal pathogens Botrytis cinerea , Monilinia fructicola , Sclerotinia sclerotiorum , Alternaria alternata, and Colletotrichum gloeosporioides . The antifungal effect of hexanal vapor was dependent on concentration and treatment duration, but sensitivity of the pathogens varied. All spores of B. cinerea and M. fructicola were killed after exposure to 900 μL/L for 12 h at 20 °C, and almost all were killed after a 24-h exposure to 450 μL/L. Only moderate numbers of spores were killed at a concentration of 200 μL/L. Mycelial growth of S. sclerotiorum on agar was completely inhibited after a 12-h exposure to 900 μL/L, but only slight inhibition occurred at 450 μL/L and none at 200 μL/L. Mycelium of A. alternata and C. gloeosporioides appeared more sensitive, with strong inhibition occurring after a 12-h exposure at 450 μL/L. Similar trends in spore viability and mycelial growth were observed at 7 °C. The antifungal effect of hexanal vapor was further tested on raspberry fruit naturally infected with B. cinerea and on peach fruit inoculated with spores of M. fructicola . Decay was markedly reduced in raspberry and almost completely controlled in peach after exposure to 900 μL/L hexanal vapor for 24 h. The potential of hexanal for postharvest decay control is discussed.