Characterization and Reactions of Copper (II) - Glycerol Complex

In solution, either aqueous or methanolic, the colour of copper(II)-glycerol complex (Cu-Gly) is deep midnight blue. Its presence was confirmed by its UV-VIS spectrum, which was a broad unsymmetrical band with a ƛmax ~625 nm. The Na₂SO₄ bisalt of the complex was successfully isolated and. characterized. The detailed characterization studies revealed interesting behaviours of the complex and its unique chemistry. The coordination of glycerol to Cu(IT) was evidenced by the absorption frequencies in the region 1500-1200 cm⁻¹ of the IR spectrum of the complex. The CHN analysis of the complex led to a proposed molecular formula of The uv-visible spectra showed absorption maxima at 381 nm and 625 nm with a shoulder at 531nm. The calculated 10Dq for the complex fell in the range of strong ligands. The structure of Cu-Gly complex ion was therefore suggested to be atetragonally distorted octahedron, with the two glycerolate ions lying in a square plane. The two water molecules were assumed to be weakly bonded at the axial positions. The study also indicated that coordination of glycerol to Cu(IT) was via its 1 ,2-hydroxyl positions. Oxidations of Cu-Gly complex were carried out in-situ, either in aqueous or methanolic media, using the following oxidants: HN03, Br2, Cr03, pyridiniumchlorochromate (PCC), H202, KMn04 and K2Cr207. Four of these gave oxidative products such as CO2, formic acid, oxalic acid and glyceric acid. These products were identified spectroscopically and confirmed by simple chemical tests, where necessary. To further understand the chemistry of Cu-Gly complex, the oxidations were also carried out on its insoluble intermediate and pure glycerol (uncomplexed). The results from this study, supported further by the identified products and the proposed mechanisms for the reactions, have shown that the coordination of Cu(II) was indeed at the l ,2-position of glycerol. The relative activities of the oxidants are parallel to the EO of their half reactions. Therefore a general trend in predicting the products (cleavage or noncleavage) can be postulated. The results of the study also show that Cu(IT) does play a major role in the reactions of Cu-Gly complex especially those involving electron transfer. The GC technique developed in this study is shown to be simple, reliable,practical and, hence, suitable for direct analyses of glycerol and its derivatives. No derivatization was required

1. The Synthesis And Biologi Calactivity of Some Estragole Analogues Towards Oil Palm Pollinating Weevils Elaeidobius Kamerunicus Faust 2. Alkaloid Constituents of Breynia Coronata (Euphorbiaceae)

Estragole is an attractant for the weevils Elaeidobi us kamerunicus Faust. The weevils were recently identified as an efficient pollinator of the oil palm, Elaeis guineens is Jacq. Four organic compounds,analogous to estrago1e, namely: 4-ethoxyallylbenzene, 4-isopropoxyallylenzene, 3-(4-methoxy phenyl)methyloxirane and (4-methoxyphenyl)acetaldehyde were prepared in the laboratory. Bioassay using a Y-tube olfactometer was carried out for each analogue in order to test its activity as an attractant for the weevils kamerunicus. Attractancy tests against water indicated that none of the analogues were active except for 4-ethoxyallyl benzene

Glycerol residue - a rich source of glycerol and medium chain fatty acids

Glycerol residue, a by-product of glycerol refining from a palm kernel oil methyl ester plant, was found to be a good source of glycerol and medium chain fatty acids. From analyses of twelve samples, it was found to contain, on average, 20.2 % glycerol and 6.6 % fatty acids. The fatty acids comprised mainly C8:0 (30.3 %), C10:0 (9.4 %) and C12:0 (40.8 %)

Testing of glyceryl monoesters for their antimicrobial susceptibility and their influence in emulsions.

Natural anti-microbial agents have received great attention in the cosmetic preservation area due to their well-documented safety profile. The anti-microbial activities of palm-based glyceryl monoesters (monolaurin, monocaprylin and monocaprin) were compared with commercially available tea tree oil and potassium sorbate against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Aspergillus niger, using the anti-microbial susceptibility testing procedure. Monolaurin was found to exhibit excellent inhibitory activity against S. aureus and Asp. niger, whereas potassium sorbate and tea tree oil had no activity against Asp. niger and S. aureus, respectively. Monocaprylin was shown to have low inhibitory activity against E. coli, and no inhibitory activity towards P. aeruginosa. On the other hand, tea tree oil had a higher inhibitory activity than monolaurin at 2% against E. coli but showed no activity against P. aeruginosa. Similar trends were observed for monocaprin and monolaurin which showed no anti-microbial activity towards P. aeruginosa as well as E. coli. Interestingly, the presence of monolaurin was not only effective as a preservative, but was also found to induce the formation of liquid crystals at concentrations as low as 0.5%. The formation of liquid crystals is said to enhance the stability and functionality of cosmetic emulsions

Effect of compositions in nanostructured lipid carriers (NLC) on skin hydration and occlusion.

Purpose: To study the effects of varying lipid concentrations, lipid and oil ratio, and the addition of propylene glycol and lecithin on the long-term physical stability of nanostructured lipid nanocarriers (NLC), skin hydration, and transepidermal water loss. Methods: The various NLC formulations (A1-A5) were prepared and their particle size, zeta potential, viscosity, and stability were analyzed. The formulations were applied on the forearms of the 20 female volunteers (one forearm of each volunteer was left untreated as a control). The subjects stayed for 30minutes in a conditioned room with their forearms uncovered to let the skin adapt to the temperature (22°C±2°C) and humidity (50%±2%) of the room. Skin hydration and skin occlusion were recorded at day one (before treatment) and day seven (after treatment). Three measurements for skin hydration and skin occlusion were performed in each testing area. Results: NLC formulations with the highest lipid concentration, highest solid lipid concentration, and additional propylene glycol (formulations A1, A2, and A5) showed higher physical stability than other formulations. The addition of propylene glycol into an NLC system helped to reduce the particle size of the NLC and enhanced its long-term physical stability. All the NLC formulations were found to significantly increase skin hydration compared to the untreated controls within 7 days. All NLC formulations exhibited occlusive properties as they reduced the transepidermal water loss within 7 days. This effect was more pronounced with the addition of propylene glycol or lecithin into an NLC formulation, whereby at least 60% reduction in transepidermal water loss was observed. Conclusion: NLCs with high lipid content, solid lipid content, phospholipid, and lecithin are a highly effective cosmetic delivery system for cosmetic topical applications that are designed to boost skin hydration

An improved method for the preparations of nanostructured lipid carriers containing heat-sensitive bioactives.

Heat-sensitive bioactive compounds such as β-carotene and tocols, are widely used in the pharmaceutical and cosmetic fields. Their chemical stability in delivery systems is one of the major concerns in the production of nanostructured lipid carriers (NLCs). A previously established high-temperature high-pressure homogenisation technique involved in the preparation of NLCs can cause degradation of heat-sensitive compounds. Therefore, a novel preparation process needs to be developed to minimise the degradation of heat-sensitive active compounds during the preparation of NLCs. In this work, modified methods A and B were designed to minimise the degradation of β-carotene and tocols during the production of NLCs. These methods improved the chemical stability of heat-sensitive bioactive compounds (β-carotene and tocols) significantly compared to the previously established method. The physical stability of the formulation was maintained throughout study duration

Nanostructured lipid carriers (NLC) for efficient delivery of palm phytonutrients

Palm phy­tonu­tri­ents found in crude palm oil con­sist of carotenes and tocols as well as other minor com­po­nents includ­ing sterols, squa­lene, ubiquinones, coen­zyme Q10 and phos­pho­lipids. Palm phy­tonu­tri­ents con­tains all the nat­u­rally occur­ring phy­tonu­tri­ents present in crude palm oil, whereas com­mer­cially avail­able indi­vid­ual phy­tonu­tri­ents, such as Gold-tri E and Tocomin 50% mainly con­sist of palm tocotrienols. The encap­su­la­tion of palm phy­tonu­tri­ents by nanos­truc­tured lipid car­ri­ers (NLC) was inves­ti­gated using Trans­mis­sion Elec­tron Microscopy. NLC was proven to effec­tively encap­su­late palm phy­tonu­tri­ents in oil droplets. Based on the par­ti­cle size analy­sis and rhe­o­log­i­cal study, NLC was found to be the most phys­i­cally sta­ble deliv­ery sys­tem when com­pared to the macro-emulsion and the nano-emulsion car­ri­ers. The long-term chem­i­cal sta­bil­ity of the palm phy­tonu­tri­ent using β-carotene as the pro­to­type active in NLC was also deter­mined. The degra­da­tion of β-carotene in NLC was lower when com­pared to the macro-emulsion and the nano-emulsion car­ri­ers. The effi­cacy of NLC as a deliv­ery sys­tem and the effect of the addi­tion of lecithin and propy­lene gly­col to the NLC for­mu­la­tion were also stud­ied. The para­me­ters inves­ti­gated were skin hydra­tion and trans-epidermal water loss (TEWL). NLC with the pres­ence of 1% lecithin and 2% propy­lene gly­col were found to enhance skin hydra­tion and pre­vent water loss

A Comparative Study on the Mechanical, Thermal and Morphological Characterization of Poly(lactic acid)/Epoxidized Palm Oil Blend

In this work, poly(lactic acid) (PLA) a fully biodegradable thermoplastic polymer matrix was melt blended with three different epoxidized palm oil (EPO). The aim of this research was to enhance the flexibility, mechanical and thermal properties of PLA. The blends were prepared at various EPO contents of 1, 2, 3, 4 and 5 wt% and characterized. The SEM analysis evidenced successful modification on the neat PLA brittle morphology. Tensile tests indicate that the addition of 1 wt% EPO is sufficient to improve the strength and flexibility compared to neat PLA. Additionally, the flexural and impact properties were also enhanced. Further, DSC analysis showed that the addition of EPO results in a decrease in Tg, which implies an increase in the PLA chain mobility. In the presence of 1 wt% EPO, TGA results revealed significant increase in the thermal stability by 27%. Among the three EPOs used, EPO(3) showed the best mechanical and thermal properties compared to the other EPO’s, with an optimum loading of 1 wt%. Conclusively, EPO showed a promising outcome to overcome the brittleness and improve the overall properties of neat PLA, thus can be considered as a potential plasticizer

Modification of olefinic double bonds of unsaturated fatty acids and other vegetable oil derivatives via epoxidation: A review

Modificación del doble enlace olefínico en ácidos grasos insaturados y en derivados de aceites vegetales via epoxidación: Revisión. La alta tensión del anillo en los epóxidos hace que estos compuestos intermediarios sean muy versátiles. Los aceites vegetales epoxidados están ganando mucha atención como materia prima renovable y respetuosa con el medio ambiente con diversas aplicaciones industriales, tales como plastificantes, aceites base para lubricantes, tensioactivos, etc. Por esta razón, se han publicado numerosos trabajos sobre el desarrollo de métodos de epoxidación y el número todavía es creciente. Esta revisión aporta información sobre enfoques sintéticos y aplicaciones de aceites vegetales epoxidados.The highly strained ring in epoxides makes these compounds very versatile intermediates. Epoxidized vegetable oils are gaining a lot of attention as renewable and environmentally friendly feedstock with various industrial applications such as plasticizers, lubricant base oils, surfactants, etc. Numerous papers have been published on the development of the epoxidation methods and the number is still growing. This review reports the synthetic approaches and applications of epoxidized vegetable oils