Preparation of n‐3 Polyunsaturated Phosphatidylglycerol from Salmon Roe Lipids by Phospholipase D and In Vitro Digestion

Abstract

Phosphatidylglycerol (PG) is a highly functional phospholipid (PL), which has many physiological functions. However, naturally occurring PG binding n‐3 polyunsaturated fatty acid (n‐3 PUFA) is low in content, resulting in a scarcity of industrial bio‐resources of n‐3 PUFA enriched PG. The current study investigates the preparation of salmon roe PG (SRPG) from three types of salmon roe lipids and glycerol via phospholipase D (PLD)‐mediated transphosphatidylation. The yields of SRPG obtained from salmon roe total lipid (SRTL) and salmon roe PL (SRPL) are higher than those obtained from purified salmon roe phosphatidylcholine (SRPC) in aqueous system. Following a 24 h reaction with 0.75 U PLD, SRTL, and SRPL yield up to 96.4 mol% and 96.7 mol% SRPG, respectively. In addition, more fatty acids are released from synthesized SRPG via hydrolysis by pancreatic enzymes than from SRPC and soybean PC in in vitro digestion model. Fatty acids at the sn‐2 position of SRPG are completely liberated by 0.04 U of phospholipase A2 (PLA2) during a 6 h reaction, whereas fatty acids of SRPC are partially unhydrolyzed even after a 24 h reaction. Our results suggest that SRPG converted from salmon lipids by PLD is a functional PL with high bioavailability of n‐3 PUFAs. Practical Applications: Phosphatidylglycerol rich in n‐3 PUFAs is prepared from salmon roe lipids (SRPG) catalyzed by PLD. The SRPG yields reach 96.4 mol% and 96.7 mol% of phosphatidylcholine contained in SRTL and SRPL, respectively, in aqueous reaction system. Fatty acids rich in n‐3 PUFAs at sn‐2 position of prepared SRPG are rapidly liberated by PLA2 in an in vitro digestion model.

The Effect of n-3 PUFA Binding Phosphatidylglycerol on Metabolic Syndrome-Related Parameters and n-3 PUFA Accretion in Diabetic/Obese KK-Ay Mice

“…We repeated the PLD-catalyzed transphosphatidylation to prepare sufficient amounts of n-3 PUFA-PG for the animal experiment. The purity of the n-3 PUFA-PG was greater than 95% (Supplemental Figure S1), as confirmed by high performance chromatography as described in our previous paper [13].…”

“…The crude PLs were obtained by the acetone precipitation of salmon roe lipids, as in a previous study [13]. The obtained insoluble precipitate (crude PLs) of 4.5 g was dissolved in 200 mL ethyl acetate and mixed with 200 mL of 0.2 M sodium acetate buffer (pH 5.6) containing 10 mM CaCl 2 ; then, 75 g glycerol was added.…”

“…It has been demonstrated as well that PG-liposome decreases TNF-α production of lipopolysaccharide-stimulated macrophages in vitro [11]. On the other hand, we reported the preparation of n-3 PUFA-PG from salmon roe PL through phospholipase D (PLD)-mediated transphosphatidylation [12,13]. n-3 PUFA-PG has been given attention as a highly functional lipid with properties of both PG and n-3 PUFAs.…”

The changes of phospholipid degradation in sea urchin gonads (Glyptocidaris crenularis) during cold storage at 4°C

“…[ 31 ] Recent studies have shown that phospholipases C and D play an important role in the hydrolysis of PL. [ 32,33 ] This study found that phospholipase C and PLD have higher activity during storage, as shown in Figure 4. Studies have shown that phospholipase C and PLD catalyze TAG to produce FFA and PUFA.…”

Reactive Deep Eutectic Solvents (RDESs): A New Tool for Phospholipase D-Catalyzed Preparation of Phospholipids

“…Moreover, it has been used for the preparation of plasmid-DNA lipid and polymeric nanovaccines showing that anionic PLs could increase antigen delivery, transport, and stability [75]. Unfortunately, PG could be recovered only in small amounts from natural sources and, even if it has been prepared by different groups [76][77][78], the possibility to set-up new strategies of synthesis is mandatory especially for the biomedical investigations.…”