Lipase-catalyzed selective enrichment of omega-3 polyunsaturated fatty acids in acylglycerols of cod liver and linseed oils: Modeling the binding affinity of lipases and fatty acids.

Present study employed molecular modeling method to elucidate the binding affinity of lipases with fatty acids of different chain lengths; and investigated the effects of lipases positional and fatty acids specificity on omega-3 polyunsaturated fatty acids (ω-3 PUFAs) enrichment in cod liver and linseed oils. Among the lipases studied, molecular modeling showed the active sites of Candida rugosa lipase (CRL) had a low C-Docker interactive energy for saturated (SFA) and monounsaturated (MUFA) fatty acids which predicted CRL to have highest preferences to selectively hydrolyze resulting in efficient enrichment of ω-3 PUFAs. Verification experiments showed the SFA and MUFA in the acylglycerol fraction includes monoacylglcyerols (MAG), diacyglycerols (DAG), and triacylglycerols (TAG) of CRL-hydrolyzed cod liver oil decreased from the initial 25.21 to 16.88% and 45.25 to 32.17%, respectively. In addition, CRL-hydrolyzed cod liver oil demonstrated 88.36% of ω-3 PUFAs enrichment. The regio-distribution of fatty acids in CRL-hydrolyzed cod liver oil were not significantly different than that of cod liver oil indicating the ω-3 PUFAs enrichment was due to fatty acids selectivity and not positional selectivity of CRL.

Development of mineral oil free offset printing ink using vegetable oil esters.

Until the middle of this century, fats and oils are the major raw material source for paints, coating and lubricating applications. These markets are completely taken over by petroleum based stocks due to their abundance and versatility. However, recent public awareness to use environmentally acceptable products that minimize pollution, are compatible to human health and readily biodegradable created opportunities for vegetable oils for application in paints and printing inks. The formulation of vegetable oil methyl ester based 'green' offset printing ink that reduces the volatile organic compounds (VOC) has been discussed in the present study. Methyl esters of rapeseed, soybean, rice bran and palm oil have been prepared and their physical properties have been measured and compared with standard petroleum feed stock. Varnishes were prepared with these esters and their properties are also compared with that of the petroleum based products. Rheological properties of the inks are also evaluated and compared with standard printing ink using petroleum based solvent. In general performance of the ester-based printing inks are comparable with that of the mineral oil based product. On the basis of tack stability and gloss, ester based inks are much superior than the mineral oil based products. In conclusion, a new non-volatile diluent for printing ink has been developed. The diluent is made from common vegetable oils like rapeseed, soybean, rice bran and palm oil, a renewable source that is environmental friendly. Vegetable oil esters offer a cost effective solution for mineral oil based printing ink to meet VOCs regulations.

Synthesis and characterization of polymeric linseed oil grafted methyl methacrylate or styrene.

Syntheses of wholly natural polymeric linseed oil (PLO) containing peroxide groups have been reported. Peroxidation, epoxidation and/or perepoxidation reactions of linseed oil, either under air or under oxygen flow at room temperature, resulted in polymeric peroxides, PLO-air and PLO-ofl, containing 1.3 and 3.5 wt.-% of peroxide, with molecular weights of 2 100 and 3 780 Da, respectively. PLO-air contained cross-linked film up to 46.1 wt.-% after a reaction time of 60 d, associated with a waxy, soluble part (PLO-air-s) that was isolated with chloroform extraction. PLO-ofl was obtained as a waxy, viscous liquid without any cross-linked part at the end of 24 d under visible irradiation and oxygen flow. Polymeric peroxides, PLO-air-s and PLO-ofl initiated the free radical polymerization of both methyl methacrylate (MMA) and styrene (S) to give PMMA-graft-PLO and PS-graft-PLO graft copolymers in high yields with Mw varying from 37 to 470 kDa. The polymers obtained were characterized by FT-IR, (1)H NMR, TGA, DSC and GPC techniques. Cross-linked polymers were also studied by means of swelling measurements. PMMA-graft-PLO graft copolymer film samples were also used in cell-culture studies. Fibroblast cells were well adhered and proliferated on the copolymer film surfaces, which is important in tissue engineering.