555-44-2Relevant articles and documents
Enzymatic transesterification of palm olein with nonspecific and 1,3-specific lipases
Ghazali,Hamidah,Che Man
, p. 633 - 639 (1995)
The enzymatic transesterification of palm olein was conducted in a low-moisture medium with nonspecific and 1,3-specific lipases from microbial sources. The enzymes were first immobilized on Celite, lyophilized for 4 h and then added to a reaction medium that consisted of 10% (wt/vol) palm olein in water-saturated hexane. The catalytic performance of the enzymes was evaluated by determining the changes in triglyceride (TC) composition and concentrations by reverse-phase high-performance liquid chromatography (HPLC) and the formation of free fatty acids by titration. Studies with lipase from Candida rugosa showed that the degree of hydrolysis was reduced by drying the immobilized preparation and that the best drying time was 4 h. In all cases, the transesterification process resulted in the formation of PPP, a TG initially undetected in the oil, and increases in the concentrations of OOO (1.3-2.1 -fold), OOL (1.7-4.5-fold), and OLL (1.7-4.3-fold), where P, O, and L are palmitic, oleic, and linoleic acids, respectively. SOS (where S is stearic acid), another TC not detected in the oil, was synthesized by Rhizomucor miehei and Pseudomonas lipases, with the latter producing more of this TG. There was a corresponding decrease in the concentrations of POP, PLP, POO, and POL. PPP concentration ranged from 1.9% (w/w) for Mucor javanicus lipase to 6.2% (w/w) for Pseudomonas lipase after 24 h. The greatest degree and fastest rate of change were caused by Pseudomonas lipase, followed by the enzymes from R. miehei and Aspergillus niger. The effects of transesterification and hydrolysis of palm olein by the various lipases resulted in changes in the overall degree of saturation of the triglyceride components. There seems to be no clear correlation between the enzyme positional specificity and the products formed. Possible mechanisms for the formation of PPP, OOL, OLL, OOO, and SOS are discussed. Copyright
Monomyristin and monopalmitin derivatives: Synthesis and evaluation as potential antibacterial and antifungal agents
Jumina,Nurmala, Asma,Fitria, Anggit,Pranowo, Deni,Sholikhah, Eti Nurwening,Kurniawan, Yehezkiel Steven,Kuswandi, Bambang
, (2018/12/11)
In the present work, monoacylglycerol derivatives, i.e., 1-monomyristin, 2-monomyristin, and 2-monopalmitin were successfully prepared from commercially available myristic acid and palmitic acid. The 1-monomyristin compound was prepared through a transesterification reaction between ethyl myristate and 1,2-O-isopropylidene glycerol, which was obtained from the protection of glycerol with acetone, then followed by deprotection using Amberlyst-15. On the other hand, 2-monoacylglycerol derivatives were prepared through enzymatic hydrolysis of triglycerides in the presence of Thermomyces lanuginosa lipase enzymes. The synthesized products were analyzed using fourier transform infrared (FTIR) spectrophotometer, gas or liquid chromatography-mass spectrometer (GC-MS or LC-MS), and proton and carbon nuclear magnetic resonance (1H- and13C-NMR) spectrometers. It was found that monomyristin showed high antibacterial and antifungal activities, while 2-monopalmitin did not show any activity at all. The 1-monomyristin compound showed higher antibacterial activity against Staphylococcus aureus and Aggregatibacter actinomycetemcomitans and also higher antifungal activity against Candida albicans compared to the positive control. Meanwhile, 2-monomyristin showed high antibacterial activity against Escherichia coli. The effect of the acyl position and carbon chains towards antibacterial and antifungal activities was discussed.
MALLEABLE, BIODEGRADABLE HEMOSTATIC AGENT
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, (2012/10/18)
A malleable, biodegradable hemostatic agent is provided that can be used for mechanical sealing of bleeding bone tissue, as well as a method for forming a malleable, biodegradable hemostatic agent of this type, and a medical implant having a coating that includes a malleable, biodegradable hemostatic agent of this type. The malleable, biodegradable hemostatic agent contains (a) at least one saturated glycerol-1,2,3-tri-fatty acid ester having a melting temperature above 37° C., (b) at least one filling agent present in particulate form, at least in part, and having a melting temperature above 37° C., and (c) at least one compound having a melting temperature not above 37° C. and a solubility at a temperature of 25° C. of less than 50 grams per liter of water.
