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The present work addresses the effect of partial equilibration and molecular partitioning on the interpretation of release experiments. In this regard, it is shown how release profiles and the values of extracted transport parameters are affected by the time protocol chosen for sample collection by considering a series of experiments where the latter is systematically varied. Caffeine is investigated as a main model drug because of its similar affinity for water and lipids, while monolinolein-based lipid cubic phases are chosen as host matrices because of their wide employment in release studies. Our findings point to a progressive decline in diffusion rate upon increasing the time step, that is, the gap in time between two consecutive pickups, which is a signature of increasing equilibration of caffeine concentration between the lipidic mesophase and the water phase. Furthermore, the amount of released molecules at the first pickup displays negligible changes for large time steps, indicating complete equilibration in such cases. A model is introduced based on Fick’s diffusion which goes beyond the assumption of perfect-sink conditions, a common feature of the typical theoretical approaches hitherto developed. The model is shown to account quantitatively for the experimental data and is subsequently employed to clarify the interplay of the adopted release protocol with the various transport parameters in determining the final outcome of the release process. Particularly, two additional molecular drugs are considered, namely glucose and proflavine, which are, respectively, more hydrophilic and hydrophobic than caffeine, thus allowing elucidating the role of molecular partitioning. ISSN:0743-7463 ISSN:1520-5827

Objectives: The objective of this study was to evaluate the β-monolinolein as a potential therapy for breast cancer treatment. Methods: The cytotoxic activity of β-monolinolein was evaluated by 3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and trypan blue exclusion assay. The cellular cytotoxicity and levels of cytosolic enzyme, lactate dehydrogenase (LDH), were measured by assessing μmoles of nicotinamide adenine dinucleotide/well/min. To confirm whether β-monolinolein induces apoptosis in 3,4-methylenedioxyamphetamine (MDA)- MB-231 cells, western blot and semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis were performed. Results: For the 1st time, it was demonstrated that β-monolinolein strongly inhibits the growth of MDA-MB-231 cells, with an half maximal inhibitory concentration value of 12.5 μg/ml.

The emulsification of two flavor compounds of the γ-lactone type with monolinolein liquid crystalline submicron particles is reported. The stabilization is ensured by the copolymer F127. γ-Nonalactone can be loaded in bicontinuous cubic monolinolein particles at a larger level (up to 20 wt %) than γ-decalactone (less than 15 wt %). The phase behavior of the ternary monolinolein/water/γ-nonalactone system was studied. The large γ-nonalactone content solubilized into cubosomes was corroborated by the observation of a wide cubic V2 range in the ternary phase diagram. Surprisingly, no inverted hexagonal phase was found in the system. On the contrary, the incorporation of γ-decalactone in the lipid particles gave rise to a dispersion of inverted hexagonal phase, which corresponds to a classical behavior of an oily additive. We finally determined the internal phase of particles including 10 wt % of γ-nonalactone upon increasing the F127 content. We thus found that γ-nonalactone restricts very significantly the ...

The participation of lipase in the formation of n-hexanal by homogenization of alfalfa seedlings was investigated. n-Hexanal was increased by the addition of trilinolein, dilinolein or monolinolein to the homogenate of the seedlings. Taurodeoxycholic acid sodium salt (TDCA), an inhibitor of triacylglycerol lipase, inhibited the formation of n-hexanal by 36%. These findings show that the corresponding proportion of n-hexanal was formed through the action of triacylglycerol lipase. n-Hexanal was also increased by adding the total lipids of alfalfa seedlings to the homogenate prepared with TDCA. But, when the lipids removed free fatty acids from the total lipids were added to the homogenate, the increase decreased to 18% as compared with the addition of total lipids. n-Hexanal thus also increased through the pathway, not requiring the action of the lipase and 82% of the increased n-hexanal was formed from preexisting free fatty acids. The formation pathways of n-hexanal in the seedlings were discussed.

An antifungal factor isolated from extracts of Cymbidium (Orchidaceae) roots and infected pseudobulbs was identified as monolinolein. © 1980 Kluwer Academic Publishers.

A lipid-enveloped virus (Semliki Forest virus: SFV) and a nonenveloped virus (coxsackievirus B4) were treated with neutral lipids known to be present in human milk or able to be generated by lipase activity in human milk. Triglycerides and diglycerides were inactive compared to monoglycerides and free fatty acids which were active against SFV (90% inactivation) at concentrations as low as 0.7 μM. Of the compounds tested monolinolein was the most active against SFV. None of the lipids tested were active against coxsackievirus B4. A synthetic milk (Almiron-M2), high in unsaturated triglycerides, was inactive against either virus.

SN-α-monolinolein was isolated from refined. bleached and deodorized soybean oil by silicic acid column chromatography and low temperature fractional crystallization. The concentration of this compound in soybean oil was 0.01%. The compound was identified by a combination of infrared. mass and NMR spcctrometry. The effect of SN-α-monolinolein on the oxidative stability of soybean oil was determined by measuring peroxide values and volatile compounds formation by gas chromatography. It had prooxidant activity in soybean oil.

Lipases from several seed species were shown to be relatively specific on triacylglycerols containing the major fatty acid components of the storage triacylglycerols in the same species. In a direct comparison using individual triacylglycerol as well as mixed triacylglycerol preparations, highest activities were observed in corn lipase on trilinolein and triolein, castor bean lipase on triricinolein, rapeseed lipase on trierucin, and elm seed lipase on tricaprin. This pattern of fatty acyl specificity was also observed on diacylglycerols, monoacylglycerols, and fatty acyl 4-methylumbelliferone, although the pattern became less distinct. The seed lipases were inactive on lecithins. Corn lipase was more active on tri- than di- or monolinolein, and released linoleic acids from both primary and secondary positions. As judged from the kinetics of hydrolysis of rac-glyceryl-2,3-stearate-1-oleate and rac-glyceryl-1,3-stearate-2-oleate, and of trilinolein and dilinoleins, corn lipase exerted some degree of preference in releasing fatty acid from the primary than the secondary position of a triacylglycerol. At the primary position, corn lipase was more active on oleyl ester than stearyl ester.

Monoglyceride-H2O systems in the range above about 5% H2O exhibit a varied phase behavior with a number of mesomorphic states reminiscent of those found for soap-H2O systems. There are fluid neat, stiff and “short” viscous isotropic, and plastic or stringy middle states. In the case of saturated monoglycerides, neat states prevail at low molecular weight as with monolaurin, but viscous isotropic and finally middle states appear at higher chain length as with monoarchidin and monobehenin. The phase diagrams for systems of unsaturated compounds resemble those for systems of saturated compounds, with corresponding phase regions occurring at lower temperatures. The monoelaidin-H2O system closely resembles a shifted monostearin-H2O system, neither system showing middle. Middle phase appears in a small island for monoolein and monolinolein near 90C and 20% water. Water dissolves negligible amounts of monoglycerides so that phases which are nearly 100% H2O exist for substantially all systems and conditions when H2O content is 60% or more.

Effects of 0, 0.25 and 0.5% monostearin, distearin, monolinolein or dilinolein on the oxidative stability of soybean oil were studied by measuring oxygen in the headspace of oil bottles by gas chromatography. As the levels of the monoglycerides and diglycerides increased from 0, 0.25 to 0.5%, headspace oxygen during storage decreased. The control sample (0%) was significantly different from the samples containing monostearin, distearin, monolinolein or dilinolein at α=0.05. All these mono- and di-glycerides acted as prooxidants in soybean oil.

1. Monostearin, monolinolein, and lard as compared in the rations studied were found to be practically equal for the growth of rats.