Monoacid triglycerides

Hagemann, J. W. and Rothfus, J. A. (1993). Transitions of saturated monoacid triglycerides—modeling conformational change at glycerol during alpha ->beta -> beta transformation. J. Am. Oil Chem. Soc., 70, 211-7. [28]... 

Desmedt, A., C. Culot, C. Deroanne, F. Durant, and V. Gibon, Influence of cis and irons Double Bonds on the Thermal and Structural Properties of Monoacid Triglycerides, Ibid. 67 653-660 (1990). 

Hagemann, J.W. J.A. Rothfus. Effects of chain length, conformation and a-form packing arrangement on theotetical monoacid triglyceride P -forms./. Am. Oil Chem. Soc. 1988, 65, 638. 

If the a-form is cooled rapidly it can form a sub-a-form reversibly at very low temperatures (about —50 °C in trimargarin (Chapman, 1965). These extreme temperatures are seldom reached and the normal phase change for a triglyceride -form is an irreversible transition into a jS -form. This transition takes place within seconds when pure monoacid triglycerides are cooled. 

Figure 8.55 Transition points of the a- and the two -forms in odd monoacid triglycerides (Hernqvist and Larsson, 1982).

A probable explanation of Malkin s misinterpretation of the two polymorphic forms vitreous and a (which are a and respectively) is the observation that neither showed any alternation of melting points between even and odd members in the series of monoacid triglycerides. Earlier experience has shown that only structures with vertical hydrocarbon chains were non-alternating. The fact that the /3 -form is tilted and still non-alternating can be explained, however, from the methyl end-group structure of the form, which is the same in even and odd members (Larsson, 1966). 

De Ruig, W.G. (1971) Infrared Spectra of Monoacid Triglycerides. Agriculture Research Reports 759, Centre for Agricultural Publishing and Documentation, Wageningen, The Netherlands. 

Calf pregastric lipase catalyzed hydrolysis of short and medium chain-length monoacid triglycerides temperature, pH and lipid concentration effects... 

Abstract The commercial extract from the oro-pharyngeal tissues of calf has been used as the source of pregastric lipase and has been processed to yield a partially purified sample of the pregastric lipase. The activity of this lipase against the short-chain lipid tributyrin has been determined over a range of pH and temperature values. Optimum pH conditions were within the range 5.7-6.4 and the optimum temperature was within 37-48 °C. The lipase was also used to catalyze the hydrolysis of monoacid triglycerides (C4 0-C12 0)... 

Key words Calf - pregastric lipase -tributyrin - monoacid triglycerides -Michaelis - Menten parameters... 

Calf pregastric lipase catalyzed hydrolysis of monoacid triglycerides... 

Figure 2 shows the percent values of the derived values of Fmax (relative to the value for tributyrin) against the carbon-chain length of the carboxylic acid moieties of the monoacid triglycerides. 

Fig. 2 Calf pregastric lipase catalyzed hydrolysis of monoacid triglycerides at 40 °C, pH 6.0...

Figure 19 Gibbs free energy-temperature relationship of monoacid triglyceride polymorphs. 

Desmedt, A, C Culot, C Deroanne, F Durant, V Gibson. (1990). Influence of cis and trans double bonds on the thermal and structural properties of monoacid triglycerides. J Am Oil Chem Soc 67 653-660. 

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