Methyl stearate procedure

Fig. 3A. The change in t, of the spin labels of 12-nitroxide methyl stearate (I2NS) (open circles) and 16-nitroxide methyl stearate (I6NS) (solid circles) with mitochondrial membranes of mung bean (V. radiata) as a fimction of temperature. The spin labels were mixed with a suspension of the membranes at a molar ratio of about I spin label per ISO lipids. The motion of the spin label was calculated from first-derivative esr spectra determined over a temperature range of 16°-40°C for 12NS and 0°-38°C 16NS. The straight lines were computed by linear regression analysis, and the temperature for the change in slope of the straight lines determined by a statistical procedure described by Raison and Chapman (1976). Data bom Raison and Chapman (1976).

The periodate-permanganate method used was based on a method described previously [105], but three changes from the original published procedure were found to be necessary. A sample size of 50 mg was taken for all oxidations. The same quantities of oxidant, potassium carbonate, and sodium bisulfite (26 ml, 45 mg, 1.06 g, respectively) were used for all samples. An inert marker (5 mg) of methyl palmite or stearate was added to all samples prior to oxidation to serve as a rough check on the completeness of oxidation and the recovery of fragments. 

Column chromatography on silicic acid has also been used to isolate polar fatty acid esters, and as examples, methyl 9- and 13-hydroxy-stearate [224] and the acetate derivatives of methyl 9,10-dihydroxy-myristate and 9,10-dihydroxy-palmitate [178] have been resolved by this technique. A small-scale column procedure, with Florisil as adsorbent, has been described for separating normal from 2-hydroxy fatty acid esters, i.e. the component fatty acids of sphingoglycolipids [122]. 

A one-stage procedure involving sodium catalysed transesterification between raffinose undeca-acetate and methyl esters of long-chain fatty acids (derived, for example, from salad oil) has been employed to produce raffinose fatty acid polyesters in excellent yields (>96%) their physical properties are described as similar to those of analogous sucrose polyesters." Certain carbohydrate esters of fatty acids, e.a.. sucrose mono-laurate, -palmitate, and -stearate, have been found to enhance the activity of thiabendazole, a fungicide used against Penicillium dioitatum infections of citrus fruit. The mechanism of this action remains to be clarified. ... 

Procedure B. Cool the xylene solution, add 4 ml of water and 0 6 g of sodium stearate and reflux for fifteen to thirty minutes. Dilute the mixture with 40 ml of neutral, industrial methylated spirit. 

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