Selective Functionalization of Microstructured Surfaces by Laser‐Assisted Particle Transfer

Microcavity arrays represent millions of different reaction compartments to screen, for example, molecular interactions, exogenous factors for cells or enzymatic activity. A novel method is presented to selectively synthesize different compounds in arrays of microcavities with up to 1 000 000 cavities per cm². In this approach, polymer microparticles with embedded pre‐activated monomers are selectively transferred into microcavities with laser radiation. After particle patterning, heating of the particle matrix simultaneously leads to diffusion and coupling of the monomers inside each microcavity separately. This method exhibits flexibility, not only in the choice of compounds, but also in the choice of particle matrix material, which determines the chemical reaction environment. The laser‐assisted selective functionalization of microcavities can be easily combined with the intensively growing number of laser applications for patterning of molecules and cells, which is useful for the development of novel biological assays.     

Protective effect of fresh and processed Jalapeño and Serrano peppers against food lipid and human LDL cholesterol oxidation

The potential of fresh and processed Jalapeño and Serrano pepper extracts for the control of lipid oxidation in several systems was investigated. The assays used included β-carotene/linoleate model system, striped corn oil, ground pork meat and Cu(II)-induced oxidation of human low-density lipoprotein (LDL). The results showed that all extracts were effective in at least one system, although their potency varied. Extracts of smoked Jalapeño were particularly effective. The lipid-protective effect of the extracts was mainly due to the presence of phenolic compounds, but other phytochemicals, such as chlorophylls were also involved.     

Bioaccumulation of dioxin-like substances and selected brominated flame retardant congeners in the fat and livers of black pigs farmed within the Nebrodi Regional Park of Sicily

An observational study was designed to assess the bioaccumulation of polychlorodibenzodioxins (PCDD) and polychlorodibenzofurans (PCDF), dioxin-like polychlorobiphenyls (DL-PCB), and 13 selected polybromodiphenylethers (PBDE) in autochthonous pigs reared in the Nebrodi Park of Sicily (Italy). Perirenal fat and liver samples were drawn from animals representative of three different outdoor farming systems and from wild pigs and then analyzed for the chemicals mentioned previously. The highest concentrations of PCDD + PCDF and DL-PCB were detected in the fat (0.45 and 0.35 pg World Health Organization toxicity equivalents [WHO-TE] per g of fat base [FB], respectively) and livers (12.7 and 3.28 pg WHO-TE per g FB) of the wild group, whereas the free-ranging group showed the lowest levels (0.05 and 0.03 pg WHO-TE per g FB in fat and 0.78 and 0.27 pg WHO-TE per g FB in livers). The sum of PBDE congeners was highest in wild pigs (0.52 ng/g FB in fat and 5.64 ng/g FB in livers) and lowest in the farmed group (0.14 ng/g FB in fat and 0.28 ng/g FB in livers). The contamination levels in fat and livers of outdoor pigs had mean concentration values lower than those levels reported for intensively indoor-farmed animals. In wild pigs, bioaccumulation was associated with their free grazing in areas characterized by bush fires. The results of this study aid to emphasize the quality of the environment as a factor to guarantee food safety in typical processed pig meat products, specifically from outdoor and extensive Nebrodi farming systems.     

Cost-effectiveness of self-help smokeless tobacco cessation programs.

This study assessed the cost-effectiveness of two low-intensity programs for quitting smokeless tobacco, based on results of a randomized trial with 1,069 volunteer participants. Cost data were collected for two levels of intervention: manual only (a self-help manual) and assisted self-help (the manual plus a videotape and two supportive phone calls from tobacco cessation counselors). Incremental cost-effectiveness ratios were calculated for assisted self-help vs. quitting on one's own, using the manual-only quit rate and data from another study as alternative proxies for no intervention. A threshold analysis was conducted to determine the spontaneous quit rate at which the manual-only intervention becomes more cost-effective than assisted self-help. The cost to provide and receive the assisted self-help intervention averaged US $56 per participant vs. $20 for the manual-only intervention (societal perspective, Year 2000 dollars). Estimates for incremental cost per quit for the assisted self-help intervention ranged from $922 to $1,758, depending on the proxy used for no intervention. The manual-only intervention was more cost-effective than assisted self-help if quitting among motivated chewers who do not receive treatment does not exceed 3.4%. Support from a wife or partner added little cost to a quit attempt for male chewers ($3-$4). Providing a manual, video, and brief phone counseling to smokeless tobacco users who want to quit is a reasonable use of health care resources. The self-help quitting guide also may be a cost-effective treatment, but it remains to be demonstrated whether it is more effective than quitting on one's own.     

Highly efficient enzyme-functionalized porous zirconia microtubes for bacteria filtration

In contrast to polymer membranes, ceramic membranes offer considerable advantages for safe drinking water provision due to their excellent chemical, thermal, and mechanical endurance. In this study, porous ceramic microtubes made of yttria stabilized zirconia (YSZ) are presented, which are conditioned for bacteria filtration by immobilizing lysozyme as an antibacterial enzyme. In accordance with determined membrane pore sizes of the nonfunctionalized microtube of ≤200 nm, log reduction values (LRV) of nearly 3 (i.e., bacterial retention of 99.9%) were obtained for bacterial retention studies using gram-positive model bacterium Micrococcus luteus. Immobilization studies of lysozyme on the membrane surface reveal an up to six times higher lysozyme loading for the covalent immobilization route as compared to unspecific immobilization. Antibacterial activity of lysozyme-functionalized microtubes was assessed by qualitative agar plate test using Micrococcus luteus as substrate showing that both the unspecific and the covalent lysozyme immobilization enhance the microtubes' antibacterial properties. Quantification of the enzyme activity at flow conditions by photometric assays reveals that the enzyme activities of lysozyme-functionalized microtubes depend strongly on applied flow rates. Intracapillary feeding of bacteria solution and higher flow rates lead to reduced enzyme activities. In consideration of different applied flow rates in the range of 0.2-0.5 mL/min, the total lysozyme activity increases by a factor of 2 for the covalent immobilization route as compared to the unspecific binding. Lysozyme leaching experiments at flow conditions for 1 h show a significant higher amount of washed-out lysozyme (factor 1.7-3.4) for the unspecific immobilization route when compared to the covalent route where the initial level of antibacterial effectiveness could be achieved by reimmobilization with lysozyme. The presented platform is highly promising for sustainable bacteria filtration.     

Formation of oxidising species and their role in the viscosity loss of cereal beta-glucan extracts

The aim of this study was to determine the role of the formation of radicals and hydrogen peroxide in the viscosity loss of beta-glucan extracts from oat and barley. Radicals derived from endogenous H₂O₂ were formed spontaneously in all extracts. The decomposition of H₂O₂ by catalase had little or no effect on the viscosity, and the radical formation detected and measured by electron spin resonance (ESR) spectroscopy did not predict the shelf life of crude beta-glucan extracts. The addition of FeSO₄ accelerated the radical formation and viscosity loss, revealing the sensitivity of the extract viscosity towards catalysts for oxidation. Using 50% cadoxen in the extracts slowed down the viscosity loss in all extracts but still led to a 10–70% decrease of the initial viscosities during 4 weeks of storage. The results suggest that the viscosity loss may be a result from multiple mechanisms including chemical reactions during storage as well as aggregation and conformational changes.     

Comparison of the Frying Performance of Olive Oil and Palm Superolein

Abstract: Deep‐fat frying is an important method of food preparation in which foods are immersed in hot oil. Repeated use of frying oils is a common practice, and in the presence of atmospheric oxygen it produces various undesirable reactions in used oils. Stable frying oils usually require low linolenic acid (LnA < 3%), increased oleic acid (OA > 40%), and decreased linoleic acid (LA < 50%). The aim of this study was to establish the behavior of palm superolein (PSO) (OA 45%; LA 12.5%; LnA 0.2%) and olive oil (OO) during repeated, discontinuous deep frying of French fries. The behavior of the oils under controlled heating conditions was also studied by maintaining all of the process variables the same as those in deep frying, except that there was no food in the oil. The PSO selected to be tested in this study may represent an alternative to OO as a frying medium. Although PSO presented a faster increase in some oxidation indices, such as free fatty acid and total polar compounds, for other indicators, PSO showed better behavior than OO (less formation of C8:0 and lower peroxide value). Practical Application: The super palm olein selected for use in this study can be suggested as a suitable replacement for olive oil for frying and cooking purposes because it provides higher oxidative stability besides the beneficial effects of olive oil on human health. In fact, several studies have indicated that palm oil exhibits similar frying performance to high‐oleic oils, with the advantages of greater availability in the market and a lower price.