Formation and stability of oil-in-water nanoemulsions containing rice bran oil: in vitro and in vivo assessments

Abstract Background Nanoemulsions have practical application in a multitude of commercial areas, such as the chemical, pharmaceutical and cosmetic industries. Cosmetic industries use rice bran oil in sunscreen formulations, anti ageing products and in treatments for skin diseases. The aim of this study was to create rice bran oil nanoemulsions using low energy emulsification methods and to evaluate their physical stability, irritation potential and moisturising activity on volunteers with normal and diseased skin types. Results The nanoemulsion developed by this phase diagram method was composed of 10% rice bran oil, 10% surfactants sorbitan oleate/PEG-30 castor oil, 0.05% antioxidant and 0.50% preservatives formulated in distilled water. The nanoemulsion was stable over the time course of this study. In vitro assays showed that this formulation has a low irritation potential, and when applied to human skin during in vivo studies, the nanoemulsion improved the skin's moisture and maintained normal skin pH values. Conclusion The results of irritation potential studies and in vivo assessments indicate that this nanoemulsion has potential to be a useful tool to treat skin diseases, such as atopic dermatitis and psoriasis.

Sintesi, modifica e caratterizzazione di polimeri da fonti rinnovabili

Gli argomenti trattati all’interno di questa tesi di dottorato riguardano la sintesi e la modifica di polimeri ottenuti a partire da fonti rinnovabili. L’acido polilattico (PLA) è stato modificato per ottenere film estensibili per uso alimentare. La scelta del materiale si è basata sull’analisi del suo ciclo di vita e perché è riconosciuto come sicuro per l’utilizzo nel campo alimentare. Le formulazioni testate, a base di PLA, sono state preparate con l’aggiunta di una serie di additivi utilizzati per migliorare le proprietà meccaniche del materiale. La lavorazione è stata eseguita mediante estrusione, ottenendo dei pellet a composizione omogenea successivamente lavorati nell’estrusore a bolla, modalità industriale di produzione dei film estensibili. È stata poi effettuata la sintesi diretta di nuovi poliesteri insaturi a base di dimetil succinato e 1,6-esandiolo. L’insaturazione della catena è stata ottenuta mediante l’uso, durante la sintesi, di derivati dell’olio di ricino, l’acido ricinoleico e il suo derivato insaturo metil undecenoato. Un’altra molecola insatura utilizzata è stata il citronellolo, scelto tra i terpeni. I polimeri così ottenuti sono stati modificati tramite reazioni radicaliche indotte con radiazioni UV utilizzando sostanze antibatteriche (sale 3-esadecil-1-vinilimidazolo bromuro) al fine di ottenere materiali con attività biocida a lungo termine e senza rilascio. Si è proceduto inoltre alla polimerizzazione reversibile di monomeri furanici con oli vegetali utilizzando una strategia di tipo double click. Si è partiti dalla sintesi di monomeri derivanti da oli vegetali contenenti eterocicli furanici attaccati mediante addizione tiol-enica (prima reazione click chemistry) e si è proseguito con la loro successiva polimerizzazione attraverso una reazione di tipo Diels-Alder con molecole con gruppi maleimmidici (seconda reazione click chemistry). I polimeri così ottenuti sono materiali potenzialmente auto-riparanti, grazie alla possibilità di spostare l’equilibrio verso i prodotti o i reagenti semplicemente variando le condizioni di temperatura.

Evaluación de aceites y extractos vegetales para el control de Sitophilus zeamaiz y su efecto en la calidad de semilla de maíz

Sitophilus zeamaiz es una de las especies de gorgojos que más pérdidas causa en granos almacenados en el mundo; su control se basa principalmente en productos sintéticos, que con el paso del tiempo resultan menos efectivos. En la presente investigación se evaluaron aceites vegetales de ricino, soya y extractos vegetales de neem y lila sobre poblaciones de S. zeamaiz y sus efectos sobre la germinación y parámetros fisiológicos de las plántulas. Los resultados muestran que el aceite de soya dio los mejores resultados de control, al presentar mortalidades entre un 92 y 100% a las 192 horas. Sin embargo, este aceite afecta la germinación a dosis de 2000 a 10000 ppm. El extracto de neem presentó mortalidades del 78,75 y 91,25% a las 192 horas, sin afectar la germinación ni las propiedades agronómicas. Finalmente, el aceite de ricino y el extracto de lila fueron los tratamientos que, para las condiciones del presente estudio, no mostraron altas mortalidades sobre S. zeamaiz.

Interfacial interactions and structure of polyurethane intercalated nanocomposite

Understanding the interfacial interactions between the nanofiller and polymer matrix is important to improve the design and manufacture of polymer nanocomposites. This paper reports a molecular dynamic Study on the interfacial interactions and structure of a clay-based polyurethane intercalated nanocomposite. The results show that the intercalation of surfactant (i.e. dioctadecyldlmethyl ammonium) and polyurethane (PU) into the nanoconfined gallery of clay leads to the multilayer structure for both surfactant and PU, and the absence of phase separation for PU chains. Such structural characteristics are attributed to the result of competitive interactions among the surfactant, PU and the clay surface, including van der Waals, electrostatic and hydrogen bonding.

Desenvolvimento e caracterização de um eco-compósito de poliuretano de mamona e fibra de lã canina

The Sustainability has been evidence in the world today; organizations have sought to be more and more into this philosophy in their processes, whether products or attendance. In the present work were manufactured eco-composites with animal fiber (dog wool) that is currently discarded into the environment without any use. Project phases consisted on the initial treatment of fibers with alkaline solution (NaOH) at 0.05 mols for removal of impurities, developing methods to convert these fibers (reinforcement) blended with castor oil polyurethane (matrix) in eco-composite with different proportions (5%, 10%, 15% and 20%). Fiber properties were evaluated by analysis of SEM, XRD and FTIR. The composites were produced by compression molding with dimensions 30x30x1cm. For characterization of the composites the following tests were performed: mechanical (tensile, compression, shore hardness A) according the standards and testing water absorption, moisture regain and biodegradation. The analysis of thermal properties on fibers and composites were by TG, DSC, thermal conductivity, resistivity, heat capacity and thermal resistance. Analyzing the results of these tests, it was observed that the composite reinforced with 20% showed a better thermal performance between others composites and dimensional stability when compared to commercial thermal insulation. Also is possible to observe a balance in moisture absorption of the composite being shown with its higher absorption rate in this same sample (20%). The micrographs show the fiber interaction regions with polyurethane to fill the empty spaces. In hardness and compression testing can identify that with increasing percentage of the fiber material acquires a greater stiffness by making a higher voltage is used for forming necessary. So by the tests performed in eco-composites, the highest percentage of fiber used as reinforcement in their composition obtained a better performance compared to the remaining eco-composites, reaching values very close to the PU.

Biodiesel a partir de óleos de alta acidez: desenvolvimento de um processo catalítico homogêneo

O presente trabalho visa o desenvolvimento de um processo para a produção de biodiesel partindo de óleos de alta acidez, aplicando um processo em duas etapas de catálise homogênea. A primeira é a reação de esterificação etílica dos ácidos graxos livres, catalisada por H2SO4, ocorrendo no meio de triglicerídeos e a segunda é a transesterificação dos triglicerídeos remanescentes, ocorrendo no meio dos ésteres alquílicos da primeira etapa e catalisada com álcali (NaOH) e álcool etílico ou metílico. A reação de esterificação foi estudada com uma mistura modelo consistindo de óleo de soja neutro acidificado artificialmente com 15%p de ácido oleico PA. Este valor foi adotado, como referência, devido a certas gorduras regionais (óleo de mamona advinda de agricultura familiar, sebos de matadouro e óleo de farelo de arroz, etc.) apresentarem teores entre 10-20%p de ácidos graxos livres. Nas duas etapas o etanol é reagente e também solvente, sendo a razão molar mistura:álcool um dos parâmetros pesquisados nas relações 1:3, 1:6 e 1:9. Outros foram a temperatura 60 e 80ºC e a concentração percentual do catalisador, 0,5, 1,0 e 1,5%p, (em relação à massa de óleo). A combinatória destes parâmetros resultou em 18 reações. Dentre as condições reacionais estudadas, oito atingiram acidez aceitável inferior a 1,5%p possibilitando a definição das condições para aplicação ótima da segunda etapa. A melhor condição nesta etapa ocorreu quando a reação foi conduzida a 60°C com 1%p de H2SO4 e razão molar 1:6. No final da primeira etapa foram realizados tratamentos pertinentes como a retirada do catalisador e estudada sua influência sobre a acidez final, utilizando-se de lavagens com e sem adição de hexano, seguidas de evaporação ou adição de agente secante. Na segunda etapa estudaram-se as razões molares de óleo:álcool de 1:6 e 1:9 com álcool metílico e etílico, com 0,5 e 1%p de NaOH assim como o tratamento da reação (lavagem ou neutralização do catalisador) a 60°C, resultando em 16 experimentos. A melhor condição nesta segunda etapa ocorreu com 0,5%p de NaOH, razão molar óleo:etanol de 1:6 e somente as reações em que se aplicaram lavagens apresentaram índices de acidez adequados (<1,0%p) coerentes com os parâmetros da ANP.

Color stability and surface roughness of artificial teeth brushed with an experimental Ricinus communis toothpaste

Aim: To evaluate, in vitro, the effect of brushing with a Ricinus communis -based experimental toothpaste on color stability and surface roughness of artificial teeth. Methods: Ninety artificial teeth (maxillary central incisors) in different shades, light and dark (NatusDent Triple Pressing, Dentbras) were used. Initial color (Spectrophotometer Easyshade, VITA) and surface roughness (Rugosimeter Surfcorder SE 1700, Kosakalab) readouts were performed. After baseline measurements, samples were assigned to 10 groups (n=9) according to the artificial tooth shade and type of toothpaste used during the mechanical brushing test (Pepsodent, MAVTEC): Sorriso Dentes Brancos – SDB, Colgate Luminous White - CLW (Colgate-Palmolive), Close up White Now - CWN (Unilever), Trihydral - THL (Perland Pharmacos) and Ricinus communis - RCE (Experimental). After 29,200 cycles of brushing, corresponding to 2 years of brushing by a healthy individual, new color and roughness readouts of the specimens were performed. Data (before and after the tests) were statistically analyzed (2-way repeated measures ANOVA, Tukey, p<0.05). Results: RCE toothpaste produced the greatest color stability for dark tooth shade and the second best color stability for light tooth shade. For surface roughness alteration, there was no difference (p>0.05) for any tested toothpaste regardless of tooth shade. Conclusions: The experimental Ricinus communis toothpaste did not cause color and surface roughness alteration in the artificial teeth, and it may be considered a suitable option for denture cleaning.

Síntese e caracterização de nanocompósitos magnéticos empregando polimerização radicalar em meios homogêneo (blk) e heterogêneo (miniemulsão)

Tese (doutorado)—Universidade de Brasília, Instituto de Química, Curso de Pós-Graduação em Química, 2016.

Obtenção de álcool alílico (PROP-2-EN-1-OL) a partir da glicerina derivada do biodiesel de óleo de mamona

In this work, biodiesel was produced from castor oil that was a byproduct glycerin. The molar ratio between oil and alcohol, as well as the use of (KOH) catalyst to provide the chemical reaction is based on literature. The best results were obtained using 1 mol of castor oil (260g) to 3 moles of methyl alcohol (138g), using 1.0% KOH as catalyst at a temperature of 260 ° C and shaken at 120 rpm. The oil used was commercially available, the process involves the reaction of transesterification of a vegetable oil with methyl alcohol. The product of this reaction is an ester, biodiesel being the main product and the glycerin by-product which has undergone treatment for use as raw material for the production of allyl alcohol. The great advantage of the use of glycerin to obtain allyl alcohol is that its use eliminates the large amount of waste of the biodiesel and various forms of insult to the environment. The reactions for the formation of allyl alcohol was conducted from formic acid and glycerin in a ratio 1/1, at a temperature of 260oC in a heater blanket, being sprayed by a spiral condenser for a period of 2 hours and the product obtained contains mostly the allylic alcohol .. The monitoring of reactions was performed by UV-Visible Spectrophotometer: FTIR Fourier transform, the analysis showed that these changes occur spectrometer indicating the formation of the product allylic alcohol (prop-2-en-1-ol) in the presence of water, This alcohol was appointed Alcohol GL. The absorption bands confirms that the reaction was observed in (υ C = C) 1470 -1600 cm -1 and (υ CO), 3610-3670 attributed to C = C groups and OH respectively. The thermal analysis was carried out in a thermogravimetric analyzer SDT Q600, where the mass and temperature are displayed against time, that allows checking the approximate rate of heating. The innovative methodology developed in the laboratory (LABTAM, UFRN), was able to treat the glycerine produced by transesterification of castor oil and used as raw material for production of allyl alcohol, with a yield of 80%, of alcohol, the same is of great importance in the manufacture of polymers, pharmaceuticals, organic compounds, herbicides, pesticides and other chemicals

Effects of plasticizing and crosslinking on the mechanical and barrier properties of coatings based on blends of starch and poly(vinyl alcohol)

In the last decades, intensive research has been carried out in order to replace oil-based polymers with bio-based polymers due to growing environmental concerns. So far, most of the barrier materials used in food packaging are petroleum-based materials. The purpose of the barrier is to protect the packaged food from oxygen, water vapour, water and fat. The mechanical and barrier properties of coatings based on starch-plasticizer and starch-poly(vinyl alcohol) (PVOH)-plasticizer blends have been studied in the work described in this thesis. The plasticizers used were glycerol, polyethylene glycol and citric acid. In a second step, polyethylene coatings were extruded onto paperboard pre-coated with a starch-PVOH-plasticizer blend. The addition of PVOH to the starch increased the flexibility of the film. Curing of the film led to a decrease in flexibility and an increase in tensile strength. The flexibility of the starch-PVOH films was increased more when glycerol or polyethylene glycol was added than citric acid. The storage modulus of the starch-PVOH films containing citric acid increased substantially at high temperature. It was seen that the addition of polyethylene glycol or citric acid to the starch-PVOH blend resulted in an enrichment of PVOH at the surface of the films. Tensile tests on the films indicated that citric acid acted as a compatibilizer and increased the compatibility of the starch and PVOH in the blend. The addition of citric acid to the coating recipe substantially decreased the water vapour transmission rate through the starch-PVOH coated paperboard, which indicated that citric acid acts as a cross-linker for starch and/or PVOH. The starch-PVOH coatings containing citric acid showed oxygen-barrier properties similar to those of pure PVOH or of a starch-PVOH blend without plasticizer when four coating layers were applied on a paperboard. The oxygen-barrier properties of coatings based on a starch-PVOH blend containing citric acid indicated a cross-linking and increase in compatibility of the starch-PVOH blends. Polyethylene extrusion coating on a pre-coated paperboard resulted in a clear reduction in the oxygen transmission rate for all the pre-coating formulations containing plasticizers. The addition of a plasticizer to the pre-coating reduced the adhesion of polyethylene to pre-coated board. Polyethylene extrusion coating gave a board with a lower oxygen transmission rate when the paperboard was pre-coated with a polyethylene-glycol-containing formulation than with a citric-acid-containing formulation. The addition of polyethylene glycol to pre-coatings indicated an increase in wetting of the pre-coated paperboard by the polyethylene melt, and this may have sealed the small defects in the pre-coating leading to low oxygen transmission rate. The increase in brittleness of starch-PVOH films containing citric acid at a high temperature seemed to have a dominating effect on the barrier properties developed by the extrusion coating process. 

Antiproliferative Activity Of Synthetic Fatty Acid Amides From Renewable Resources.

In the work, the in vitro antiproliferative activity of a series of synthetic fatty acid amides were investigated in seven cancer cell lines. The study revealed that most of the compounds showed antiproliferative activity against tested tumor cell lines, mainly on human glioma cells (U251) and human ovarian cancer cells with a multiple drug-resistant phenotype (NCI-ADR/RES). In addition, the fatty methyl benzylamide derived from ricinoleic acid (with the fatty acid obtained from castor oil, a renewable resource) showed a high selectivity with potent growth inhibition and cell death for the glioma cell line-the most aggressive CNS cancer.

Influence of Phase Inversion on the Formation and Stability of One-Step Multiple Emulsions

A novel method of preparation of water-in-oil-in-micelle-containing water (W/O/W(m)) Multiple emulsions using the one-step emulsification method is reported. These multiple emulsions were normal (not temporary) and stable over a 60 day test period. Previously, reported multiple emulsion by the one-step method were abnormal systems that formed at the inversion point of simple emulsion (where there is an incompatibility in the Ostwald and Bancroft theories, and typically these are O/W/O systems). Pseudoternary phase diagrams and bidimensional process-composition (phase inversion) maps were constructed to assist in process and composition optimization. The surfactants used were PEG40 hydrogenated castor oil and sorbitan oleate, and mineral and vegetables oils were investigated. Physicochemical characterization studies showed experimentally, for the First time, the significance of the ultralow surface tension point oil multiple emulsion formation by one-step via phase inversion processes. Although the significance of ultralow surface tension has been speculated previously, to the best of our knowledge, this is the first experimental confirmation. The multiple emulsion system reported here was dependent not only upon the emulsification temperature, but also upon the component ratios, therefore both the emulsion phase inversion and the phase inversion temperature were considered to fully explain their formation. Accordingly, it is hypothesized that the formation of these normal multiple emulsions is not a result of a temporary incompatibility (at the inversion point) during simple emulsion preparation, as previously reported. Rather, these normal W/O/W(m) emulsions are a result of the simultaneous occurrence of catastrophic and transitional phase inversion processes. The formation of the primary emulsions (W/O) is in accordance with the Ostwald theory and the formation of the multiple emulsions (W/O/W(m)) is in agreement with the Bancroft theory.

Spray drift of pesticides arising from aerial application in cotton

This paper presents results from field studies carried out during the 1993-1998 Australian cotton (Gossypium hirsutum L.) seasons to monitor off-target droplet movement of endosulfan (6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepin 3-oxide) insecticide applied to a commercial cotton crop. Averaged over a wide range of conditions, off-target deposition 500 m downwind of the field boundary was approximately 2% of the field-applied rate with oil-based applications and 1% with water-based applications. Mean airborne drift values recorded 100 m downwind of a single flight line were a third as much with water-based application compared with oil-based application. Calculations using a Gaussian diffusion model and the U.S. Spray Drift Task Force AgDRIFT model produced downwind drift profiles that compared favorably with experimental data. Both models and data indicate that by adopting large droplet placement (LDP) application methods and incorporating crop buffer distances, spray drift can be effectively managed.

Aracnoidite Adesiva Lombar

Spinal arachnoiditis, an inflammatory process involving all three meningeal layers as well as the nerve roots, is a cause of persistent symptoms in 6% to 16% of postoperative patients. Although spinal surgery is the most common antecedent associated with arachnoiditis, multiple causes have been reported, including infection, intrathecal steroids or anesthetic agents, trauma, subarachnoid hemorrhage and ionic myelographic contrast material--both oil soluble and water soluble. In the past, oil-based intrathecal contrast agents (Pantopaque) were associated with arachnoiditis especially when this material was introduced into the thecal sac and mixed with blood. Arachnoiditis is apparently rarely idiopathic. The pathogenesis of spinal arachnoiditis is similar to the repair process of serous membranes, such as the peritoneum, with a negligible inflammatory cellular exudate and a prominent fibrinous exudate. Chronic adhesive arachnoiditis of the lower spine is a myelographic diagnosis. The myelographic findings of arachnoiditis were divided into two types by Jorgensen et al. In type 1, "the empty thecal sac" appearance, there is homogeneous filling of the thecal sac with either absence of or defects involving nerve root sleeve filling. In type 2 arachnoiditis, there are localized or diffuse filling defects within the contrast column. MRI has demonstrated a sensitivity of 92% and a specificity of 100% in the diagnosis of arachnoiditis. The appearance of arachnoiditis on MRI can be assigned to three main groups. The MRI findings in group I are a conglomeration of adherent roots positioned centrally in the thecal sac. Patients in group II show roots peripherally adherent to the meninges--the so called empty sac. MRI findings in group III are a soft tissue mass within the subarachnoid space. It corresponds to the type 2 categorization defined by Jorgensen et al, where as the MRI imaging types I and II correspond to the myelographic type 1.

Quantitative image analysis as a tool for Yarrowia lipolytica dimorphic growth evaluation in different culture media

Yarrowia lipolytica, a yeast strain with a huge biotechnological potential, capable to produce metabolites such as γ-decalactone, citric acid, intracellular lipids and enzymes, possesses the ability to change its morphology in response to environmental conditions. In the present study, a quantitative image analysis (QIA) procedure was developed for the identification and quantification of Y. lipolytica W29 and MTLY40-2P strains dimorphic growth, cultivated in batch cultures on hydrophilic (glucose and N-acetylglucosamine (GlcNAc) and hydrophobic (olive oil and castor oil) media. The morphological characterization of yeast cells by QIA techniques revealed that hydrophobic carbon sources, namely castor oil, should be preferred for both strains growth in the yeast single cell morphotype. On the other hand, hydrophilic sugars, namely glucose and GlcNAc caused a dimorphic transition growth towards the hyphae morphotype. Experiments for γ-decalactone production with MTLY40-2P strain in two distinct morphotypes (yeast single cells and hyphae cells) were also performed. The obtained results showed the adequacy of the proposed morphology monitoring tool in relation to each morphotype on the aroma production ability. The present work allowed establishing that QIA techniques can be a valuable tool for the identification of the best culture conditions for industrial processes implementation.