The impact of lipid oxidation on the digestive efficiency of Antarctic krill oil (AKO) was explored, with a focus on the relationship between emulsification efficiency and digestive efficiency. AKO samples underwent oxidation were assessed using a simulated gastrointestinal model. Lipid oxidation was found to significantly reduce emulsification efficiency, as evidenced by a lower density of emulsified lipid droplets in oxidized AKO compared to fresh AKO during simulated intestinal digestion, as observed via optical microscopy and cryo-scanning electron microscopy. The total lipid emulsification efficiency was higher in fresh AKO than in oxidized AKO. Additionally, the release of free fatty acids was lower in oxidized AKO ((14.06 ± 0.42) mmol/L digestive juice) compared to fresh AKO ((17.44 ± 0.68) mmol/L digestive juice) at the end of simulated gastrointestinal digestion. These results suggest that lipid oxidation impairs its emulsification during the process of gastrointestinal digestion by producing less quantity but larger size of lipid droplets, which limit enzymatic access and subsequent absorption during digestion. This underscores the critical role of lipid oxidation level in determining the bioavailability of AKO and highlights the necessity for optimized handling and storage practices to preserve its nutritional integrity in dietary supplements.

This study aimed to search for the optimum antioxidant mixture for improvement of the stability of high-oleic sunflower oil. Seven antioxidants including vitamin E, phytic acid, antioxidant of bamboo leaves, rosemary extract, tea polyphenols, ascorbyl palmitate (AP) as well as tea polyphenol palmitate (TPP) were used. Peroxide value, free radicals and Rancimat induction time results all proved that TPP was the best single antioxidant. Therefore, TPP was selected to mix with other antioxidants to form composite antioxidants. The combination of TPP and AP revealed the best antioxidant efficiency among the composite antioxidants comprised of two and three constituents in the oil. By optimizing the mixture proportions, the best antioxidant activity could be achieved when combining 480 mg/kg TPP with 40 mg/kg AP. The high-oleic sunflower oil sample (containing 480 mg/kg TPP and 40 mg/kg AP) had 1.96-fold longer shelf life (prediction by Rancimat method) compared with the blank sample.

Lipid oxidation products (LOPs) are widely present in many lipid- containing foods. They usually enter the gastrointestinal tract from dietary sources and/or are produced in vivo. Part of LOPs were absorbed into the blood and transported into tissues. A growing bulk of evidence suggests that LOPs, mainly reactive aldehydes and oxysterols, are potentially involved in the pathogenesis of many chronic diseases, such as atherosclerosis, Alzheimer's disease, and inflammatory bowel disease. This review summarizes the current knowledge of the adverse effects, cytotoxicity, and the main mechanisms of LOPs involvement in humans and animals.

In the present study, an effective shot-gun lipidomic methodology was established to determine the glycerophospholipid (GP) molecular species of two species of edible marine whelks (Chlorostoma rusticum and Neverita didyma). Simultaneously, the lipid content, lipid classes, phospholipid (PL) subclasses and fatty acid compositions were also investigated. Over 210 molecular species of GP including glycerophosphocholine, lysoglycerophosphocholine, glycerophosphoethanolamine, lysoglycerophosphoethanolamine, glycerophosphoserine, lysoglycerophosphoserine, glycerophosphoinositol and lysoglycerophosphoinositol were characterized in the two abovementioned whelk species. The predominant GP molecular species contained n-3 long chain polyunsaturated fatty acid (n-3 LC-PUFA), especially docosahexaenoic acid and eicosapentaenoic acid. Meanwhile, PL (57.70–58.86% of total lipids) and PUFA (21.69–37.68% of total FA) take large proportions in whelk lipids. Among PL, phosphatidylcholine (50.58–52.41 mol%) and phosphatidylethanolamine (27.67–32.73 mol%) were dominant. Therefore, marine whelks turn out to be promising source of n-3 LC-PUFA existed in PL form and thus directly contribute to the health benefits of consumer.

Nutrient loss, caused by lipid oxidation and hydrolysis, occurs in the scallop adductor muscle during refrigerated storage. To retard this process, chitosan coating with inclusion of antioxidant of bamboo leaves (AOB) and potassium sorbate (PS) were used. Results indicated the coatings employed could significantly inhibit the increases in total number of colonies, total volatile basic nitrogen, peroxide value, thiobarbituric acid-reactive substances, lipase activity and free fatty acid content as well as the decrease in contents of triacylglycerols, phosphatidylcholine, phosphatidylethanolamine and polyunsaturated fatty acids (PUFA) in the scallop adductor muscle during refrigerated storage. After 8 days, the contents of PUFA, eicosapentaenoic acid and docosahexenoic acid in the control adductor muscle decreased by 46.91, 47.46 and 45.50%, respectively, while the corresponding values were 35.93–36.68, 34.01–36.45 and 32.73–37.50%, respectively, for AOB- and PS-coated adductor muscles. Therefore, chitosan coatings incorporated with AOB and PS could retard nutrient loss by inhibiting lipid oxidation and hydrolysis.

Sea cucumber is a "healthy" food. Although previous studies have suggested that sea cucumber might serve as a potential rich source of polyunsaturated fatty acids (PUFAs) enriched phospholipid (PL), the molecular species of its PL has rarely been reported. In this study, some 200 glycerophospholipid (GP) species belonging to seven classes in processing by-products (spawns and intestines) of sea cucumber (Stichopus japonicus) were characterized for the first time. Most of the dominant GP species contained PUFAs, especially eicosapentaenoic acid (EPA, 20:5n-3) and arachidonic acid (AA, C20:4n-6). Meanwhile, the lipids contained high levels of PUFA (25.35–45.12% of total FAs) and polar lipid (65.55–85.95% of total lipids) but low levels of cholesterol (0.63–2.26% of total lipids). Among PL, phosphatidylcholine (38.34–65.56 mol%) was dominant. Therefore, PUFA enriched PL in sea cucumber may account for their nutritional and health beneficial effects. Meanwhile, by-products of Stichopus japonicus by-products provide great potential as health-promoting food ingredients.