Structured lipids enriched with unsaturated fatty acids produced by enzymatic acidolysis of silkworm pupae oil using oleic acid

Abstract

Desilked silkworm (Bombyx mori L.) pupae oil has been identified as a valuable source of unsaturated fatty acids (UFAs). However, direct consumption is a food safety issue due to the presence of sn-1,3 triacylglycerols (TAGs), including palmitic acid (PA). A simple, selective and safe conversion to structured triacylglycerols (STAGs) with high UFA content is highly desirable. Novel STAGs with low PA and high a-linolenic acid (ALA), oleic acid (OA) and linoleic acid (LA) content were synthesized from silkworm pupae oil using a solvent-free system catalyzed by Lipozyme RM IM. Crystallization and melting profiles were determined using thermograms, and optimal conditions involved an enzyme load of 7%, a silkworm pupae oil TAG to OA molar ratio of 1:5, and a reaction temperature of 60°C. The content of PA and stearic acid decreased from 41.04 to 20.11%, while UFAs increased from 61.12 to 77.88%. The STAGs exhibited lower crystallization (À15.44°C) and melting (À23.47°C) profiles than TAGs (4.64 and À5.58°C, respectively).Practical applications: The presented methods using a solvent-free system enable STAGs to be synthesized using a natural substrate (desilked silkworm pupae oil). A simple, selective and safe conversion to STAGs with high UFA content and low PA content is highly desirable. This STAG is rare in nature and chemical synthesis is cumbersome. This STAG could be applied as a clinical treatment for nutritional enhancement with a beneficial effect on human health because of the high content of the ALA.

Enzymatic synthesis of structured lipids from grape seed (Vitis vinifera L.) oil in associated packed bed reactors

“…Similar fatty acid profiles were reported by other authors [2,23,46,47], demonstrating that the oil has high nutritional quality and is an important source of essential polyunsaturated fatty acids, especially linoleic and α-linolenic acids, which are important in the prevention of cardiovascular diseases, atherosclerosis, and diabetes [2,48,49]. The intake of oleic acid is associated with the improvement of cardiovascular and bowel health and reduction of LDL cholesterol [1,11,48,49]. The antioxidant properties of unsaturated fatty acids have been explored by the food and cosmetic industries; and are used as nutraceutical ingredients in product formulations [46].…”

“…In the majority of published studies, synthesis of MLM-type TAGs is carried out in batch reactors [1,2,13,18,[23][24][25]. Batch operation has low yield for use on an industrial scale, low rate of conversion of the substrate into product, and possible shear stress of the support due to mechanical agitation during the process [26,27].…”

Nutritional, functional, and allergenic properties of silkworm pupae

“…About 70%–80% of the fatty acid content of silkworm pupae is unsaturated, while about 1% is unsaponifiable matter in oil, including campesterol, β‐sitosterol, and cholesterol. In particular, silkworm pupae have almost 71% α‐linolenic acid content (Pereira et al., 2003 ; Rao, 1994 ; Zhao, Li, et al, 2015 ; Zhao, Wang, et al., 2015 ). Silkworm pupae are a good source of functional fatty acids.…”

Production of Structured Triacylglycerols Containing Palmitic Acids at <i>sn</i>-2 Position and Docosahexaenoic Acids at <i>sn</i>-1, 3 Positions

“…STAGs with low PA and high α-linolenic acid ALA , oleic acid OA and linoleic acid LA content were synthesized from silkworm pupae oil using a solvent-free system by Zhao et al 22 . Recently, refined olive oil was enriched with PA and DHA via lipase-catalyzed acidolysis reaction using Novozym 435 in hexane 23 .…”