This review briefly summarizes recent developments in the construction of biologically/environmentally compatible chemical machinery composed of soft matter. Since environmental and living systems are open systems, chemical machinery must continuously fulfill its functions not only through the influx and generation of molecules but also via the degradation and dissipation of molecules. If the degradation or dissipation of soft matter molecular building blocks and biomaterial molecules/polymers can be achieved, soft matter particles composed of them can be used to realize chemical machinery such as selfpropelled droplets, drug delivery carriers, tissue regeneration scaffolds, protocell models, cell-/tissuemarkers, and molecular computing systems.

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This study investigated the roles of rice mono- and diacylglycerol (rice MDG) and commercial MDG on solid structure formation of rice bran oil (RBO) and RBO-anhydrous milk fat (AMF) blends after the crystallized blends were aged at 5°C for 12 or 24 h and stored at 30°C for 12 or 24 h. The rice MDG was prepared using a pilot-scale molecular distillation (MD) unit to evaporate out the free fatty acids from deodorizer distillate (DD) at 120, 140 and 160°C at 0.1 Pa. It was found that increasing the distillation temperature during MD process from 120°C to 140°C resulted in higher contents of rice MDG and γ-oryzanol in the unevaporated fraction (UMD) compared to those in DD. Although UMD increased solid fat content in RBO-UMD blend, it could not stabilize the solid fat phase in the RBO-UMD or RBO-AMFUMD oleogel at 30°C storage. In the presence of UMD, RBO-AMF-UMD blends remained in a liquid state although it contained a high content (38.54%) of saturated fatty acids. On the other hand, with the addition of commercial MDG rich in palmitic acid, RBO-MDG and RBO-AMF-MDG blends were able to retain the volume of solid fat phase in the oleogels provided that the RBO-MDG and RBO-AMF-MDG oleogels were aged at 5°C for at least 12 h. This study implicated that the presence of 1% MDG surfactant having different acyl chains from the major fatty acids in the bulk oil phase, as well as aging regime, could be used to assist solid structure forming process of RBO and RBO-AMF oleogels.

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Elionurus muticus is a grass from Pampa biome and it is an excellent alternative as natural source of citral in southern Brazil. The essential oil has a high citral level (80%) and presents variability for other important chemical compounds. The present studies indicated its cytotoxic effect against Artemia salina and also suggested its application in the control of pathogenic fungi. E. muticus could become an alternative to synthetic fungicides for using in agro-industries and also to screen and develop novel types of selective and natural fungicides.

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The present study was adopted to evaluate the antioxidant efficacy of medium chain fatty acid (caprylic, capric and lauric) rich rice bran oils in comparison to rice bran oil in terms of altered biochemical parameters of oxidative stress following sodium arsenite treatment in rats. Animals were divided into ten groups; five normal groups and five arsenite treated groups. Results showed that activities of antioxidant enzymes in liver, brain and erythrocyte membrane increased with the administration of rice bran oil and MCFA rich rice bran oils both in normal and arsenite treated cases. Lipid peroxidation increased with the administration of sodium arsenite, but again administration of rice bran oil and MCFA rich rice bran oils decreased the lipid peroxidation. Caprylic acid rich rice bran oil showed the best ameliorative effects.

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An experimental investigation was carried out with the aim to evaluate the effect of talc on the extraction yield and quality of extra virgin olive oils from Coratina olives after production and during storage. A significant effect of talc, added in the malaxer, on both yield and oil quality was observed. The addition of 1% talc lead to a 15% decrease of the residual oil in the olive-pomace, while higher amounts of talc did not determine further significant variations. The use of talc caused also a significant decrease of the peroxide value and tocopherols and a significant increase of carotenoids, chlorophylls, phenols, antioxidant activity and K₂₇₀, while no influence was detected on free fatty acids and K₂₃₂. Finally, during storage the differences among the oils were maintained as immediately after their production, with the exception of chlorophylls.

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D-limonene in water nanoemulsion is prepared from an optimum formulation by low energy process at room temperature. The phase behavior of d-limonene/isotridecanol ethoxylate-6/ isopropyl alcohol /water system is systematically investigated to identify the optimum formulation. The microstructure of intermediate phases has been characterized by optical microscope and small angle X-ray diffraction. The microstructure of formulation concentrate has been further determined by means of electrical conductivity. The droplet size of nanoemulsion has been determined by light scattering and correlated with their microstructure. The results show that d-limonene nanoemulsion with droplet size of ca. 40 nm is obtained via the addition of the optimum formulation, which is a microemulsion, directly into water. This process involves composition change from a bicontinuous structure.

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We report a soft liquid-phase adsorption (SLPA) technique for the fabrication of organic semiconductor films on wettability-patterned substrates using toluene/water emulsions. Wettabilitypatterned substrates were obtained by the UV-ozone treatment of self-assembled monolayers of silane coupling agents on glass plates using a metal mask. Organic semiconductor polymer films were formed selectively on the hydrophobic part of the wettability-patterned substrates. The thickness of the films fabricated by the SLPA technique is significantly larger than that of the films fabricated by dip-coating and spin-coating techniques. The film thickness can be controlled by adjusting the volume ratio of toluene to water, immersion angle, immersion temperature, and immersion time. The SLPA technique allows for the direct production of organic semiconductor films on wettability-patterned substrates with minimized material consumption and reduced number of fabrication steps.

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The effect of cholesterol on the uptake of a fluorinated general anesthetic, sevoflurane (SF, fluoromethyl 2,2,2-trifluoro-1-[trifluoromethyl]ethyl ether) was studied by multinuclear, high-resolution nuclear magnetic resonance (NMR) spectroscopy in combination with a pulsed-field gradient technique. Using large unilamellar vesicles of egg phosphatidylcholine/egg phosphatidylglycerol/cholesterol as model fluid cell membranes, the ¹⁹F and ¹H NMR chemical shifts, longitudinal relaxation times (T₁), and diffusion coefficients (D^eff) were systematically analyzed to quantify the modulation of SF uptake to the lipid membrane by cholesterol. All NMR parameters (chemical shift, T₁, and D^eff) showed that SF uptake is limited by the presence of cholesterol in the membrane. It was found that SF uptake at 40 mol% cholesterol is limited to 50%–60% of the partitioning fraction in the absence of cholesterol in the membrane. This finding is attributed to the loss of motional freedom in the rigid membrane environment, as demonstrated by the gradual slowdown of lipid mobility D^eff with increase in cholesterol concentration from 0 mol% to 40 mol%.

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Mammalian lungs are covered with lipid-protein complexes or pulmonary surfactants. In this work, which aimed towards the less expensive production of artificial pulmonary surfactants, we produced surfactants composed of egg yolk lecithin (eggPC), palmitic acid, and hexadecanol (= 0.30/0.35/0.35, mol/mol/mol ) containing different amounts of Hel 13-5 (NH₂-KLLKLLLKLWLKLLKLLL-COOH) as a substitute for the proteins in native pulmonary surfactants. Surface pressure (π)–molecular area (A) and surface potential (DV)–A isotherms of the mixtures were measured via the Wilhelmy and ionizing ²⁴¹Am electrode methods, respectively. The interactions between the lipid components and Hel 13-5 led to variations in the surface pressure caused by the expulsion of fluid components from the surface. Furthermore, the π–A and DV–A isotherms featured large hysteresis loops for the surfactant that contained a small amount of Hel 13-5 during compression and successive expansion cycling. To elucidate the morphology, the phase behavior was visualized in situ at the air–water interface by means of fluorescence microscopy; the images suggested less effective interactions between Hel 13-5 and the unsaturated PC in eggPC despite the similarity of their monolayer properties.

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During our screening program for agrochemicals from Chinese medicinal herbs and wild plants, the essential oils of Evodia calcicola and Evodia trichotoma leaves were found to possess strong repellency against the red flour beetle Tribolium castaneum adults, the cigarette beetle Lasioderma serricorne adults and the booklouse Liposcelis bostrychophila. The two essential oils obtained by hydrodistillation were investigated by GC-MS. The main components of E. calcicola essential oil were identified to be (-)-β-pinene (44.02%), β-phellandrene (20.93%), ocimene (16.49%), and D-limonene (9.87%). While the main components of the essential oil of E. trichotoma were D-limonene (69.55%), 1R-a-pinene (11.48%), caryophyllene (2.80%) and spathulenol (2.24%). Data showed that T. castaneum was the most sensitive than other two stored product insects. Compared with the positive control, DEET (N, N-diethyl-3- methylbenzamide), the two essential oils showed the same level repellency against the red flour beetle. However, the essential oil of E. trichotoma showed the same level repellency against the cigarette beetle, while E. calcicola essential oil possessed the less level repellency against L. serricorne, relative to the positive control, DEET. Moreover, the two crude oils also exhibited strong repellency against L. bostrychophila, but lesser level repellency than the positive control, DEET. Thus, the essential oils of E. calcicola and E. trichotoma may be potential to be developed as a new natural repellent in the control of stored product insects.

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This study deals with evaluating antioxidant and antimicrobial activities of the peel of pea (Pisum sativum), with particular attention to the content of some bioactive compounds. Total content of polyphenols and flavonoids of Pisum sativum peel extracts, including a crude aqueous extract, a methanolic extract and an ethyl acetate extract was carried out according to the standard methods to assess their corresponding antioxidant activities. The organic solvents extracts antioxidant activities, determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, ferric reducing (FRAP) assay and 2,2 azinobis 3-ethylbenzo-thiozoline-6-sulfonic acid (ABTS) assay, were relatively high. The highest activity was found in ethyl acetate extract. The antimicrobial activities of extracts were also assessed. The highest MIC value was occurred with E.Coli (850 µg/ml) when using ethyl acetate extract. From the results obtained, Pisum sativum peel can be considered as a very good source of health promoting compounds.

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Studies on the interaction of different generation poly (amido amine) (PAMAM) dendrimers (2G, 4G and 6G) and liposomes of different compositions were carried out by a combined turbidity, dynamic light scattering and atomic force microscopic measurements. Liposomes comprising soy lecithin (SLC, negative surface charge), 1, 2-palmitoyl-sn-glycero-3-phosphatidylcholine (DPPC, mildly positive surface charge), 1,2-dipalmitoyl-sn-glycero-3-phospho-(1’-rac-glycerol (DPPG, negatively charged) and a biologically simulated mixture of DPPC + DPPG (7:3, M/M, negatively charged) were used as model bilayers. 30 wt% cholesterol was used in each combination as it is known to control the fluidity of membrane bilayers. Silica was used as a negatively charged hard sphere model with an aim to compare the results. Both the turbidity and hydrodynamic diameter values of all the liposomes, except DPPC, passed through maxima upon the progressive addition of PAMAM; the effect was insignificant in case of DPPC. Formation of dendriosome, a complex formed between dendrimer and liposome, resulted in the charge reversal of the negatively charged liposomes. Interaction between PAMAM and liposome was found to be governed by electrostatic as well as hydrogen bonding. Generation dependent PAMAM activity followed the order: 6G >4G>2G in terms of overall dendrimer concentration. However, interestingly, the order was reverse when PAMAM activity was considered in terms of total end group concentrations. AFM studies reveal the rupture of bilayer structure upon addition of dendrimer.

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In this paper, the volatiles emitted by flowers and various parts of the flower of a rare spontaneous Italian red (peel and flesh) apple named “Pelingo”, were analyzed by SPME with the aim of identifying the contribution of each one to the whole aroma profile. Linalool was the most abundant volatile of flowers: from 43.0% in the flower buds, to 17.6% in the stylus and stigma headspace. The second most represented volatile was (E,E)-α-farnesene mainly emitted by the mature flowers (32.2%). Benzenoid compounds also have been identified: benzyl-alcohol is the most representative (1.0-16.5%) in all the samples except flower buds, while benzyl acetate (5.7%) and methyl salicylate (7.7%) are mainly present in the calyx and in the mature flowers respectively but not in the flower buds. Benzenoid compounds are the attractors for pollinator, probably for this reason were not detected in the headspace of flower buds.

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Nanodiscs are a relatively new class of nanoparticles composed of amphiphilic α-helical scaffold peptides and a phospholipid bilayer, and find potential applications in various fields. In order to identify the minimum number of amino acid residues of an amphiphilic α-helical peptide that leads to nanodisc formation, seven peptides differing in lengths (22-, 18-, 14-, 12-, 10-, 8-, and 6-mers) that mimic and modify the C-terminal domain of apoA-I (residues 220–241) were synthesized. At a concentration of 0.3 mM, the 6- and 8-mer peptides did not present any surface activity. In case of the 10-mer peptide, the aqueous surface tension initially decreased and reached a constant value of 51.9 mN/m with the 14-, 18-, and 22-mer peptides. Moreover, upon mixing the surface-active peptides (14-, 18-, and 22-mers) with dipalmitoylphosphatidylcholine (DMPC) liposomes (2.5:1, peptide : DMPC), the turbid DMPC liposome solution rapidly became transparent. Further analysis of this solution by negative-stain transmission electron microscopy (NS-TEM) indicated the presence of disk-like nanostructures. The average diameter of the nanodiscs formed was 9.5 ± 2.7 nm for the 22-mer, 8.1 ± 2.7 nm for the 18-mer, and 25.5 ± 8.5 nm for the 14-mer peptides. These results clearly demonstrate that the surface properties of peptides play a critical role in nanodisc formation. Furthermore, the minimum length of an amphiphilic peptide from the C-terminal of apoA-I protein that can lead to nanodisc formation is 14 amino acid residues.

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