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The mechanism of how plant-derived nanovesicles are uptaken by cells remains unknown. In this study, the garlic-derived nanovesicles (GDVs) were isolated and digested with trypsin to remove all surface proteins. Digested GDVs showed less uptake compared to undigested GDVs, confirming that the surface proteins played a role in the endocytosis. On the cell side (HepG2), interestingly, blocking the CD98 receptors significantly reduced the uptake of GDVs. During the cellular internalization of GDVs, we observed that some surface proteins of GDVs were co-localized with CD98. A total lysate of the GDV surface showed a high presence of a mannose-specific binding protein, II lectin. Blocking GDV II lectin (using mannose preincubation) highly reduced the GDV internalization, which supports that direct interaction between II lectin and CD98 plays an important role in internalization. The GDVs also exhibited in vitro anti-inflammatory effect by downregulating proinflammatory factors on the HepG2 cells. This work contributes to understanding a part of the GDV internalization process and the cellular anti-inflammatory effects of garlic.

Chromatographic techniques were used to prepare rosmarinic acid rich extract from Orthosiphon aristatus. Such extract is highly required for herbal product development because of its remarkable bio...

Background & Aims Nourishment of gut microbiota via consumption of fermentable fiber promotes gut health and guards against metabolic syndrome. In contrast, how dietary fiber impacts type 1 diabetes is less clear. Methods To examine impact of dietary fibers on development of type 1 diabetes in the streptozotocin (STZ)-induced and spontaneous non-obese diabetes (NOD) models, mice were fed grain-based chow (GBC) or compositionally defined diets enriched with a fermentable fiber (inulin) or an insoluble fiber (cellulose). Spontaneous (NOD mice) or STZ-induced (wild-type mice) diabetes was monitored. Results Relative to GBC, low-fiber diets exacerbated STZ-induced diabetes, whereas diets enriched with inulin, but not cellulose, strongly protected against or treated it. Inulin’s restoration of glycemic control prevented loss of adipose depots, while reducing food and water consumption. Inulin normalized pancreatic function and markedly enhanced insulin sensitivity. Such amelioration of diabetes was associated with alterations in gut microbiota composition and was eliminated by antibiotic administration. Pharmacologic blockade of fermentation reduced inulin’s beneficial impact on glycemic control, indicating a role for short-chain fatty acids (SCFA). Furthermore, inulin’s microbiota-dependent anti-diabetic effect associated with SCFA-independent restoration of interleukin 22, which was necessary and sufficient to ameliorate STZ-induced diabetes. Inulin-enriched diets significantly delayed diabetes in NOD mice. Conclusions Fermentable fiber confers microbiota-dependent increases in SCFA and interleukin 22 that, together, may have potential to prevent and/or treat type 1 diabetes., Graphical abstract

Three zeolites were treated with magnesium nitrate hexahydrate (Mg(NO3)2⋅6H2O) salt to generate active magnesium oxide (MgO)–zeolite catalysts for the isomerization of oleic acid to give the iso-oleic acid (precursor of isostearic acid). Isostearic acid is a crucial component used in the formulation of bio-lubricants including cosmetic and personal care products. The treatment step is intended to poison (or neutralize) the external acid sites of the zeolites, thus inhibiting the formation of by-products (i.e., dimer fatty acids). The acid sites, crystallinity, thermal property, morphology and elemental composition of the zeolites before and after treatments were investigated by scanning electron microscopy, fourier-transform spectroscopy, thermogravimetric analysis, and x-ray powder diffraction. In addition, the effect of a calcination step after treatment was examined to determine if this step was necessary to obtain an active and stable catalyst. As expected, the higher the concentration of MgO on the zeolites, the less dimer was detected in the isomerization products, while the conversion of oleic acid and selectivity of iso-oleic acid remained at a relatively high level. This is promising because the MgO has deprotonated the external acids of the zeolites to generate a high purity isostearic acid that is potentially suitable for personal care products.

There is tremendous demand for the development of new bio-based materials with bioactive properties to replace antimicrobials or antibiotics that are no longer effective against microorganisms. For this current research, a new group of phenolic branched-chain fatty acids (n-PBC-FA), hybrid molecules of natural monophenols (i.e., thymol, carvacrol and creosote) and mixed fatty acid (i.e., derived from soybean and safflower oils), are efficiently produced through a process known as arylation. The reactions for producing these compounds involve a combination of the modified H+‐Ferrierite zeolite catalyst and water co-catalyst which give 72.4%, 77.2%, and 48.8% yields for thymol-safflower branched-chain fatty acids (BCFA), creosote-safflower BCFA and carvacrol-BCFA, respectively. The ratios (2.2–17 wt/wt) of water co-catalyst to zeolite catalyst were found to have a significant influence on the arylation reaction as the water co-catalyst depressed the isomerization reaction and favored the arylation reaction. This modified H+-ferrierite zeolite can be regenerated by calcining at 500 °C in air for 2 h, and the activity of the catalyst can be maintained at a relatively stable level without significant deactivation even after 7 reused cycles. The n-PBC-FA products are thoroughly characterized by gas chromatography and high performance liquid chromatography with high-resolution mass spectrometry. Most importantly, these products can be purified up to 97 wt% by the wiped-film molecular distillation device.

In order to study the structure-activity relationship of antibacterial bio-based epoxy polymers made from phenolic branched fatty acids (phenolic BCFAs), a series of curing agents (i.e., phenolic BCFA-amides (phenolic BCFAAs)) were prepared from phenolic BCFAs and polyamines at 90 ℃ and 160 ℃. Those phenolic BCFAs were made from phenol, thymol, carvacrol, and creosote, respectively, while the polyamines were ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA) and hexamethylenediamine (HDA). The prepared curing agents were then used to make different antimicrobial bio-epoxy polymers with a commercial epoxy resin, diglycidyl ether of bisphenol A (DGEBA). All the monomers were thoroughly characterized by Fourier-transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (NMR). Two bio-epoxy polymers, phenol-BCFA (EDA) and creosote BCFA (EDA), were found to be most active against both Gram-positive and Gram-negative bacteria. The leaching experiments on the phenol-BCFA (EDA) showed no signs of small molecules (i.e., biocides) leaking out of the polymer to inactivate the bacteria. Most importantly, the reusability study indicated that the polymer was inherently antibacterial and maintained its efficacy for at least three uses. This study presents important findings on the antimicrobial activity of individual phenolics, polyamines and molecular weights of the curing agents, and the evidence demonstrates that the amphiphilicity contributes to the key impact of the antimicrobial activity of the bio-epoxy polymers.

Novel phenolic branched-chain fatty acids (PBC-FAs) were evaluated for their antimicrobial properties against both gram-positive ( Listeria innocua , Bacillus subtilis , Enterococcus faecium ) and gram-negative ( Escherichia coli , Salmonella Typhimurium, and Pseudomonas tolaasii ) bacteria. In addition, PBC-FA derivatives, such as PBC-FA methyl ester mixture, methyl-branched fatty acid mixtures, and trimethylsilyl-PBC-FA methyl esters, were synthesized to study the structure activity relationship. Results showed that PBC-FAs were a potent antimicrobial against gram-positive bacteria with MICs of 1.8 to 3.6 μg/ml. The compounds were less effective against gram-negative bacteria. Derivatives of PBC-FAs and an equimolar mixture of oleic acid and phenol all had MICs above 233 μg/ml against both gram-positive and gram-negative bacteria. Comparison of antimicrobial activities of the PBC-FAs with those of the derivatives suggests that the carboxylic group in the fatty acid moiety and the hydroxyl group on the phenol moiety were responsible for the antimicrobial efficacy. Growth curves of L. innocua revealed that PBC-FAs prevented bacterial growth, while MBC-FAs only delayed the onset of rapid growth of L. innocua . Our results demonstrated that the novel PBC-FAs have potential for use as antimicrobials against gram-positive bacteria.

Three new iso-oleic ester derivatives (i.e., isopropyl ester (IOA-iPrE, 6), n-butyl ester (IOA-n-BuE, 7), and 2-ethylhexyl ester (IOA-2-EHE, 8)) were synthesized from iso-oleic acid (IOA, 4) using a standard esterification method. These esterified alcohols were chosen because of their bulky and branched-chain alkyl groups which can reduce melting point in comparison to a smaller alkyl group such as methyl ester. The differential scanning calorimetry (DSC), cloud point and pour point results showed that esters 6, 7, and 8 had much lower melting transition temperatures and cold flow properties than the methyl (IOA–FAME, 5) and parent 4. The oxidative and thermal stability by pressure (P-DSC) and thermogravimetric analysis (TGA) results also showed a very similar trend where the bulkier and branched-chain alkyl esters had better stability than the smaller headgroup esters.

Dimer acids are a class of important intermediates that are widely used in many practical applications including polyamides, lubricants, paints, and coatings. They are typically produced through the polymerization (dimerization) of tall oil fatty acids (TOFA) using clays as catalysts. Although this technology is well developed and efficient, the drawback is that the clay catalysts cannot be recycled, generating considerable amounts of hazardous waste. In addition, these products consist of a complex mixture of dimer acids, trimer acids, and polymeric acids. This complexity has limited the ability to thoroughly evaluate their chemical structures. This study reports an advanced recycle zeolite catalysis process using plant-based soybean oil fatty acid (SOFA) which can selectively control the structure formation of the dimer acids and result in yields that are just as efficient as the TOFA technology. The detailed chemical structures of products were thoroughly verified by Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), gas chromatography–mass spectroscopy (GC–MS), and liquid chromatography-mass spectrometry (LC–MS). The reuse process was demonstrated by conducting ten recycle experiments and maintaining high yields, which shows great potential in replacing clay to produce dimer acids. These valuable insights into the structures of the dimer acid products and catalyst reuse results will improve the value and production of dimer acids to meet new industrial uses.

Epoxy resins are one class of important reactive pre-polymers used in the coating industry. To manufacture epoxy resins with antimicrobial properties, active quaternary ammonium groups are often introduced into the polymeric backbones following resin polymerization reactions for structure modification. However, these complicated approaches associated with these types of reactions make the commercialization of the antimicrobial epoxy polymers uneconomical, impractical and inconvenient. Besides, quaternary ammonium groups are undesirable because the hydrophilicity of the groups makes the resins less water-resistant. In order to simplify the development of antimicrobial epoxy polymers, we prepared an amide by reacting novel bio-based phenolic-branched fatty acids with ethylenediamine. The resulting amide was cured into a commercial epoxy resin -- diglycidyl ether of bisphenol A (DGEBA), which was solution-cast into epoxy polymer films. The antimicrobial activities of the resulting epoxy polymer films were investigated. The crude phenolic branched fatty acid amides (PBC-FAAs) as curing agents were separated and characterized by thin-layer chromatography, proton nuclear magnetic resonance (1H-NMR), gas chromatography-mass spectrometry (GC MS), liquid chromatography-mass spectrometry (LC/MS) and Fourier-transform infrared spectroscopy (FT-IR). The thermal and mechanical properties of the polymer films were also investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA). Cured epoxy films prepared from purified PBC-FAA exhibited antimicrobial activity against Listeria innocua. However, the crude, unpurified PBC-FAA-cured epoxy film showed much more promising antimicrobial activity against both Listeria innocua (Gram positive) and Escherichia coli (Gram negative).

The gut epithelium acts to separate host immune cells from unrestricted interactions with the microbiota and other environmental stimuli. In response to epithelial damage or dysfunction, immune cells are activated to produce interleukin (IL)-22, which is involved in repair and protection of barrier surfaces. However, the specific pathways leading to IL-22 and associated antimicrobial peptide (AMP) production in response to intestinal tissue damage remain incompletely understood. Here, we define a critical IL-36/IL-23/IL-22 cytokine network that is instrumental for AMP production and host defense. Using a murine model of intestinal damage and repair, we show that IL-36γ is a potent inducer of IL-23 both in vitro and in vivo. IL-36γ–induced IL-23 required Notch2-dependent (CD11b+CD103+) dendritic cells (DCs), but not Batf3-dependent (CD11b−CD103+) DCs or CSF1R-dependent macrophages. The intracellular signaling cascade linking IL-36 receptor (IL-36R) to IL-23 production by DCs involved MyD88 and the NF-κB subunits c-Rel and p50. Consistent with in vitro observations, IL-36R– and IL-36γ–deficient mice exhibited dramatically reduced IL-23, IL-22, and AMP levels, and consequently failed to recover from acute intestinal damage. Interestingly, impaired recovery of mice deficient in IL-36R or IL-36γ could be rescued by treatment with exogenous IL-23. This recovery was accompanied by a restoration of IL-22 and AMP expression in the colon. Collectively, these data define a cytokine network involving IL-36γ, IL-23, and IL-22 that is activated in response to intestinal barrier damage and involved in providing critical host defense.

Biodiesel is an alternative diesel fuel derived mainly from the transesterification of plant oils with methanol or ethanol. This fuel is generally made from commodity oils such as canola, palm or soybean and has a number of properties that make it compatible in compression-ignition engines. Despite its many advantages, biodiesel has poor cold flow properties that may impact its deployment during cooler months in moderate temperature climates. This work is a study on the use of skeletally branched-chain-fatty acid methyl esters (BC-FAME) as additives and diluents to decrease the cloud point (CP) and pour point (PP) of biodiesel. Two BC-FAME, methyl iso-oleate and methyl iso-stearate isomers (Me iso-C18:1 and Me iso-C18:0), were tested in mixtures with fatty acid methyl esters (FAME) of canola, palm and soybean oil (CaME, PME and SME). Results showed that mixing linear FAME with up to 2 mass% BC-FAME did not greatly affect CP, PP or kinematic viscosity (ν) relative to the unmixed biodiesel fuels. In contrast, higher concentrations of BC-FAME, namely between 17 and 39 mass%, significantly improved CP and PP without raising ν in excess of limits in the biodiesel fuel standard specification ASTM D 6751. Furthermore, it is shown that biodiesel/Me iso-C18:0 mixtures matched or exceeded the performance of biodiesel/Me iso-C18:1 mixtures in terms of decreasing CP and PP under certain conditions. This was taken as evidence that additives or diluents with chemical structures based on long-chain saturated chains may be more effective at reducing the cold flow properties of mixtures with biodiesel than structures based on long-chain unsaturated chains.

Isostearic acids (IA) are highly utilized for industrial purposes especially in the area of biolubricants, such as cosmetics and slip additives for polyolefin and related copolymer films. This study was designed to develop a zeolitic catalysis process for efficient IA production through isomerization of fatty acids. The process utilized zeolite protonated Ferrierite with a small amount of base additive to neutralize (i.e., poison) the acidic sites on the external surfaces of the zeolite particles to prevent side reactions. Of the six base additives examined, the proton sponge combined with the zeolite protonated Ferrierite was found to be the most effective for this isomerization. With only 0.5 wt% proton sponge additive to 5.0 wt% Ferrierite, the dimers were successfully suppressed from 20.6 wt% yield to 2.42 wt% with an IA yield of 83.4 wt% and a 98 % conversion.

Ferrierite zeolite solid is an excellent catalyst for the skeletal isomerization of unsaturated linear-chain fatty acids (i.e., oleic acid) to unsaturated branched-chain fatty acids (i.e., iso-oleic acid) follow by hydrogenation to give saturated branched-chain fatty acids (i.e., isostearic acid). In order for the isomerization process to be cost effective, the spent zeolite catalyst must be capable of regeneration for subsequent uses. We report a much improved zeolite regeneration protocol. The Ferrierite zeolite is efficiently regenerated by heating at 115 °C for 20 h after each use and treatment with an acid solution after every 5th or 6th use. This approach allows the catalyst to be successfully used at least 20 times without significant decrease in conversion and selectivity. The unused and regenerated catalysts have been thoroughly characterized by various analytical techniques. The improved catalyst regeneration protocol should enable cost effective, large scale production of isostearic acid via zeolite-catalyzed skeletal isomerization.

The global interest in reducing the use of petroleum resources to mitigate climate change has created a need for the continuing demand for environmentally friendly systems from renewable resources to produce clean and sustainable technology. One promising approach involves the development of catalysts and process improvements to increase the efficiency of the chemical modification reactions. In this study, sunflower oil was used in the skeletal isomerization reaction to introduce methyl branching at the alkyl fatty acid chain of the oil (methyl-branched-chain triglycerides (MBC-TG)) in the presence of a modified H+-BETA zeolite catalyst. Such modification of the oil is proposed to improve its low temperature fluidity, by preventing precipitation at low temperatures. The modified catalyst was easy to handle and separate from the reaction products. The products were thoroughly characterized by common analytical instruments. To evaluate the practicality of this environmentally friendly process, a techno-economic model was constructed to estimate the production cost.

There is significant research interest in developing new industrial materials from vegetable oils and animal fats. Such biobased materials can be more environmentally friendly because they tend to have good biodegradability and are derived from renewable resources. This paper describes a catalytic approach for the addition of phenol to the olefinic site of oleic acid using the H-ferrierite zeolite. A number of experimental parameters were examined, including different reaction components and their ratios, and reaction conditions. Under optimized conditions, phenol-branched-chain fatty acid isomers were obtained in up to 70% yield. The materials were characterized using various analytical techniques, including GC, GC–MS, and HPLC–MS.

Iso-oleic acid is a mixture of C18-unsaturated branched-chain fatty acid isomers with a methyl group on various positions of the alkyl chain, which is the product of the skeletal isomerization reaction of oleic acid and is the intermediate used to make isostearic acid (C18-saturated branched-chain fatty acid isomers). Methyl iso-oleate, a mixture of C18-unsaturated branched-chain fatty acid methyl ester isomers, is obtained via acid catalyzed esterification of iso-oleic acid with methanol. The branched-chain materials are liquid at room temperature and their “oiliness” property makes them an attractive candidate for the lubricant industry. In this paper, we report characterization of these branched-chain materials using comprehensive two-dimensional GC with time-of-flight mass spectrometry (GC × GC/TOF-MS) and their physical and lubricity properties using tribology measurements.

Diphenylamine sulfate (DPAS) and diphenylamine hydrochloride (DPACl) salts were found to be highly active catalysts for esterification and substantial transesterification of inexpensive greases to fatty acid methyl esters (FAME). In the presence of catalytic amounts of DPAS or DPACl and excess methanol, the free fatty acids as well as the acylglycerols in waste greases were converted to FAME at 125 °C within 1 h. Although the DPAS and DPACl catalysts were found to have similar catalytic activities to their parent liquid acids (i.e., sulfuric and hydrochloric acids) the diphenylammonium salts are much easier to work with than concentrated liquid acids.

For decades, lubricants and hydraulic fluids were almost entirely based on petroleum. In recent years, the potential health risks of these materials as a result of their poor biodegradability have ...

Three strains of Pseudomonas (P.) bacteria were screened for their capabilities of degrading chemically synthesized saturated branched-chain fatty acids (sbc–FA). Mixtures of sbc–FA with the methyl-branch located at various locales along the fatty acid were used as a carbon feedstock in shake-flask culture. Utilization (and hence degradability) of the sbc–FA was monitored based on positive bacterial growth, fatty acid recovery rates and chromatographic (gas chromatography (GC) and GC-mass spectroscopy (MS)) analysis of the recovered carbon source. P. putida KT2442 and P. oleovorans NRRL B-14683 were both able to grow on sbc–FA utilizing 35 wt% and 27 wt% of the carbon source, respectively after 144 h. In contrast, P. resinovorans NRRL B-2649 exhibited the most efficient use of the carbon source by utilizing 89 % of the starting material after 96 h resulting in a cell dry weight (CDW) of 3.1 g/L. GC and GC–MS analysis of the recovered carbon source revealed that the bacterial strains selectively utilized the isostearic acid in the sbc–FA mixture, and a new group of C10, C12, C14 and C16-linear and/or branched-chain fatty acids (approximately 4–29 wt%) were formed during degradation.

The development of viable technologies for producing green products from renewable fats and oils is highly desirable since such materials can serve as replacements for non-renewable and poorly biodegradable petroleum-based products. Mixtures of saturated branched-chain fatty acid isomers (sbc-FAs), commonly referred to as isostearic acid, are important intermediates for the production of biodegradable lubricants, cosmetics, emollients, and hydraulic fluids. Present methods for producing sbc-FAs, however, often give low yields of sbc-FAs or sbc-FA preparations with a high content of dimer acid fatty acid co-products. This study reports an improved route to synthesizing sbc-FAs from monounsaturated fatty acids using a modified H-Ferrierite zeolite catalyst in conjunction with small amounts of triphenylphosphine additive. The yields of sbc-FAs (up to 80 wt%) and co-products (up to15 wt%) were determined using a modification of a previously reported GC method. A more detailed analysis of the distribution of sbc-FA isomers in the products was made by the combined use of GC × GC-TOF-MS. Additionally, it was found that the H-Ferrierite zeolite catalyst was recyclable and reusable up to 10 times without significant loss of activity and selectivity for sbc-FAs.

Biodiesel (BD) is a renewable fuel for compression ignition engines that is composed of the simple alkyl esters, usually methyl-, of fatty acids (FAME). It is typically produced via base-catalyzed transesterification between refined vegetable oil or animal fat (e.g., soybean oil, tallow) and an alcohol (e.g., methanol). This process can, however, be marginally cost-effective due to the high feedstock and processing costs. It is thus desirable to develop new catalytic routes that can efficiently convert less expensive feedstocks to BD. We report here on the application of a series of diarylammonium based homogeneous and heterogeneous catalysts for converting a particularly low value, low quality lipid, trap grease, to FAME. In the course of a 1-h reaction at 125 °C these catalysts simultaneously esterified the free fatty acids (>90 wt% of the substrate) and transesterified the acylglycerols (

“Isostearic acids” (IA) are branched-chain fatty acids that are nontoxic and biodegradable in nature. They are predominantly used in cosmetics because of their superior moisturizing properties as they are odorless, provide smooth spreading and a non-tacky feeling when applied onto skin. They can also be used in applications which require excellent thermo-stability and low flow temperature properties. The existing older technology produces IA at low yields, which limits their commercial adoption; thus, new technologies for preparing IA are needed.

Saturated branched-chain fatty acids (sbc-FAs) are found as minor constituents in several natural fats and oils. Sbc-FAs are of interest since they have lower melting points than their linear counterparts and exhibit good oxidative stability; properties that make them ideally suited in a number of applications. We (and others) have previously synthesized sbc-FAs by clay- or zeolite-catalyzed isomerization of unsaturated linear-chain fatty acids (ulc-FAs) to unsaturated branched-chain fatty acids (ubc-FAs) that were subsequently hydrogenated to the desired sbc-FAs. These acid-catalyzed isomerization reactions, however, proceed in moderate conversion and selectivity. Recently, our group found that H-Ferrierite zeolite catalyst isomerized ulc-FAs to their branched-chain counterparts in high conversion (>95%) and selectivity (85%). This paper reports the use of this type of catalyst for the preparation of a series of sbc-FAs and their ester derivatives. Selected physical properties of these branched acids and esters such as cloud point (CP) and pour point (PP), cold filter plugging point (CFPP), viscosity index (VI), thermo-oxidation stability, iodine value, and lubricity are also reported.

Isostearic acids (ISA) are important bio‐based ingredients for many commercial products such as lubricants, detergents, and cosmetics. This study is targeted to compare the efficacy of various phosphine derivatives in neutralizing the external acidic surface of zeolite which is responsible for the unwanted oligomerization during zeolite based skeletal isomerization reaction producing dimer as byproducts. Sixteen phosphine derivatives were individually evaluated with heat activated ammonium (NH₄⁺) cationic ferrierite zeolite to produce iso‐oleic acid from oleic acid which was converted to ISA through the hydrogenation process. In comparison, eight newly tested phosphine additives were found more effective than the previously reported phosphines (TPP, TPTP) to increase the product yield of iso‐oleic acid, ultimately ISA, either by suppressing the byproducts or accelerating the reaction rate as a whole. The performance depends on the electron donating capacity of central phosphorus atom of phosphine derivative attracting proton from the external surface of zeolite. This phenomenon is resulted from the combination of electronic effects and structural hindrances posed by the different substituents attached to the phosphine derivatives. The effectiveness of sixteen Lewis base phosphine additives were tested in neutralizing the external acidic surface of zeolite. The neutral outer surface of zeolite is ideal for suppressing dimer formation and thus producing the iso‐oleic acid (precursor of isostearic acid) in high yield through Lewis base‐zeolite combination skeletal isomerization reaction.

In this work we designed, simulated and developed a flexible 10 GHz patch antenna using standard microsystem technology. Liquid crystal polymer (LCP) is used as substrate and Copper (Cu) as metallization thin film. LCP and Cu are best suited for high frequency applications because of their excellent electrical properties such as resistivity and dielectric constant. To protect the antenna it is passivated and encapsulated with parylene C. Parylene C was deposited at room temperature using standard Gorham system. The effect of Cu metallization and parylene C passivation on antenna indicator parameters such as resonance frequency, input reflection coefficient, bandwidth and gain are investigated. Furthermore the specific resistance of Cu lines on LCP substrates is investigated.

Biodiesel (BD), typically consisting of fatty acid methyl esters (FAME), has received much attention because it is a renewable biofuel that contributes little to global warming compared to petroleum-based diesel fuel. The most common method used for BD production is based on the alkali-catalyzed transesterification of first-use refined oils and fats with an alcohol (e.g. methanol). These technologies, however, require significant modification when applied to second use materials such as greases because of their higher free fatty acid (FFA) content. Recently, we reported a series of insoluble porous polymer grafted diphenylammonium salts that efficiently esterified the FFA in greases to FAME. In this work, the diphenylammonium salts were supported onto two robust mesoporous silicas. The resulting catalysts had high esterification activity with >99% of the FFA in greases converted to FAME, and the FFA content in the treated greases was reduced to

Pseudomonas resinovorans, a known medium-chain-length (mcl-) poly(hydroxyalkanoate) (PHA) producer, was grown on 13-methyltetradecanoic acid (13-MTDA) and a mixture of isostearic acid (IA) isomers to produce methyl-branched mcl-PHA polymers. Shake-flask experiments revealed polymer productivities (the percent of the cell mass that is polymer) of 31 +/- 1% (n = 3) and 23 +/- 3% (n = 3) when grown in 13-MTDA and IA, respectively. Monomer content was determined by a combination of gas chromatography/mass spectrometry (GC/MS) of the acid hydrolyzed, silylated methyl esters, and nuclear magnetic resonance spectroscopy. Results showed that the mcl-PHA polymer derived from 13-MTDA was primarily composed of 3-hydroxy-7-methyloctanoic acid and 3-hydroxy-9-methyldecanoic acid (67 and 16 mol% by GC/MS, respectively). In contrast, the mcl-polymers synthesized from the IA isomeric mixture were more complex, containing both even and odd chain-length monomers as well as varying distributions of methyl-branched derivatives. The PHA distributions among the C8, C10, C12, and C14 carbon chain-length monomers included three isomers of C8, five isomers of C10, seven isomers of C12, and nine isomers of C14 each containing one linear-chain derivative and n-6 methyl-branched derivatives where n equals the total number of carbon atoms in each monomer unit (C8-C14).

The effects over time of exogenous auxins and substrate on rooting of leafy stem cuttings were simultaneously examined in Annickia chlorantha. The hypothesis that post-severance treatments and propagation environment do not temporally affect the rooting ability of leafy stem cuttings was rejected. Each of the four replicate blocks used consisted of 12 treatments from two crossed factors, substrate × auxins. Time (weeks) after insertion of cuttings in nonmist propagators was used as the third factor. Substrate × auxin × time had highly significant (P = 0.0022), whereas substrate × time and auxin × time had non-significant (P = 0.0518–0.0549) effects on rooting percentage, respectively. Substrate and auxin did not influence rooting ability. Time had highly significant (P < 0.0001) effects on rooting ability. Contrasts constructed with the different factors tested on rooting percentage allowed the dissection of the rooting period into three phases.

We successfully optimized an analytical method using gel permeation chromatography followed by direct sample introduction comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry to quantify multiple groups of targeted persistent organic pollutants and halogenated natural products (HNPs) simultaneously in fish oil samples. This new method has a wider analytical scope than the traditional approach to use multiple methods to cover each class of compounds. Our analysis revealed that the relatively more volatile and lighter organic compounds, such as polychlorinated biphenyls (PCBs), organochlorine pesticides, and other smaller organohalogen compounds, were still present in two brands of "PCB-free" cod liver oils, albeit at much lower levels than in an untreated commercial sample. Moreover, the less volatile organic compounds, such as polybrominated diphenyl ethers and brominated HNPs, were detected at similar levels in all three cod liver oils. This suggests that the commercial molecular distillation treatment used for removal of organic/inorganic toxic contaminants is only effective for the lighter organic contaminants.

A high-throughput screen at 100 microM inhibitor concentration for the BACE-1 enzyme revealed a novel spiropiperidine iminohydantoin aspartyl protease inhibitor template. An X-ray cocrystal structure with BACE-1 revealed a novel mode of binding whereby the inhibitor interacts with the catalytic aspartates via bridging water molecules. Using the crystal structure as a guide, potent compounds with good brain penetration were designed.

Biodiesel (BD) is an alternative diesel fuel derived from both vegetable oils and animal fats. Currently, most BD is made by alkali-catalyzed transesterification of a refined oil or fat, the cost of which is the major expenditure in producing BD. Yellow and brown greases are readily available renewable fats that are less expensive and hence represent attractive feedstocks for the production of BD. The high free fatty acid (FFA) content of these feedstocks, however, makes it difficult to produce BD using base-catalyzed transesterification. In this paper, we report the use of a series of diarylammonium catalysts that are highly effective in catalyzing the esterification of the FFA present in greases (12–40 wt % FFA). At a catalyst loading of 2–3 mol %, high conversions of FFA to esters (95−99%) were achieved by treating the greases with 5–20 equiv of methanol at 95 °C for 2 h. The treated greases had a final FFA content of 0.5–1 wt %. We also incorporated these diarylammonium catalysts into insoluble porous...

The self-metathesis reaction of soy, rapeseed, tall, and linseed oil fatty acids was investigated for the synthesis of symmetrical long-chain unsaturated-α,ω-dicarboxylic acids. The metathesis reactions were carried out in the presence of a Grubbs catalyst under solvent-free condition at a catalyst loading of 0.01 mol% to fatty acid substrate at 50 °C. Under these conditions, the conversions of starting unsaturated acids to metathesis products were >80% and the isolated yields of unsaturated dicarboxylic acid products were >70% of theoretical. This approach represents an effective and efficient route for the synthesis of these potentially useful dicarboxylic acids since they can serve as important intermediates in the production of several materials such as biodegradable polymers.

The self-metathesis of readily available monounsaturated FA has the potential of being an important pathway for the synthesis of symmetrical long-chain unsaturated-α,ω-dicarboxylic acids (C18−C26). Previous studies on the self-metathesis of monounsaturated FA esters using ruthenium catalysts in solution, however, suffered from low conversions as a result of the thermodynamic control of the reaction. We have found that the second-generation Grubbs catalyst can effectively catalyze the solvent-free self-metathesis of monounsaturated FA of varying purity (from 90 to 99%) to afford two important products—monounsaturated dicarboxylic acids and hydrocarbons—in very high molar conversions (>80%). This solvent-free self-metathesis reaction also works for monounsaturated FA containing additional functional groups. Reactions were conducted at catalyst loadings as low as 0.005 mol%, and turnover numbers as high as 10,800 could be obtained. This discovery represents an attractive approach to the large-scale production of useful monounsaturated-α,ω-dicarboxylic acids and long-chain unsaturated hydrocarbons by means of this solvent-free ruthenium-catalyzed self-metathesis of readily available monounsaturated FA.

Porous zirconium phosphonates containing chiral dihydroxy functionalities have been synthesized via a building block approach. Enantiopure atropisomeric bisphosphonic acids of various lengths, L1–L3, were first synthesized starting from 1,1′-bi-2-naphthol (BINOL) in multi-step sequences. Amorphous chiral porous zirconium phosphonates were then obtained by refluxing BINOL-derived bisphosphonic acids with Zr(OnBu)4 in n-BuOH, and have been characterized by powder X-ray diffraction, solid-state CP-MAS 31 P NMR, IR, TGA, adsorption measurements, circular dichroism spectroscopy, and microanalyses. These zirconium phosphonates have empirical formulae of (Zr-L1–3)·xH2O (x=4 or 5), and exhibit BET surface areas ranging from 431 to 586 m2/g. In combination with Ti(OiPr)4, these zirconium phosphonates have been used to heterogeneously catalyze the additions of diethylzinc to a wide range of aromatic aldehydes with high conversions and e.e. of up to 72%. This work represents a novel approach towards heterogeneous asymmetric catalysis. The tunability of such a molecular building block approach promises to lead to practically useful heterogeneous asymmetric catalytic processes.

Pausinystalia johimbe (K. Schum), a tree of the Central Africa humid lowlands, is exploited for its bark to supply both export and local medicinal plant markets. The gradual destruction of the forests in which Yohimbe grows coupled with unsustainable bark harvesting methods, has resulted in local scarcity of this tree species. The study examined the amenability of P. johimbe to vegetative propagation through the rooting of leafy stem cuttings using low-cost technology polythene propagators. Using single-node leafy cuttings, three experiments were investigated in Cameroon: (i) Three propagation media (sawdust and 50:50 mixture of sand and sawdust). Initially, rooting was best in the mixed medium, but subsequently, cuttings set in the sawdust rooted better than those in sand and the mixture of sand/sawdust. However, there was no significant ( P >0.05) treatment effect on rooting percentage or on the mean number of roots per cutting. (ii) Three types of auxin at 50 μg per cutting (IAA, indole-3-acetic acid; IBA, indole-3-butyric acid and NAA, 1-naphthalene acetic acid) dissolved in 10 μl of alcohol. The control treatment received 10 μl of alcohol only. Significant differences in rooting percentage occurred after 3–4 weeks between the auxin-treated cuttings and the control. Within the same period IBA-treated cuttings rooted better than those with NAA and IBA. (iii) Four leaf areas: 0, 50, 100 and 200 cm 2 . Leafy cuttings rooted better than leafless cuttings after 4–5 weeks, with 50 cm 2 leaf area being the best from week 6. Significantly higher cutting mortality ( P P. johimbe is amenable to vegetative propagation technique using juvenile single-node leafy cuttings.