## 1 Introduction  
Purpleblow maple (_Acer truncatum_ Bunge, 2n = 2x = 26) is a diploid monoecious tree species of the family Aceraceae [1]. It is a versatile, oil-producing, woody tree that is a native species widely distributed in northern China, Korea, and Japan. Unsaturated fatty acids (FAs) account up to 92% of the entire _A. truncatum_ seed oil (Aoil) [2]. In 2011, The People's Republic of China's Ministry of Health certified Aoil as a new food resource [3]. Aoil is the main plant source responsible for the large-scale production of nervonic acid (NA), found at a portion of 3-7% [4]. NA is a very-long-chain fatty acid (VLCFA) with great human health benefits, particularly relating central nervous system development. Substantial evidence has shown that a variety of neurological disorders can be linked with NA deficiency [5]. A simple method for the efficient bioaccessibility of NA is its direct intake [6]. Aoil is a novel type of plant drug with potential applications in treating the human brain and neurological problems, making it eligible for providing exogenous NA as well as other types of essential unsaturated fatty acids [7]. When Aoil is processed or stored, it can easily oxidize. The main oxidation by-products are hydroperoxides (HPs) [8]; the decomposition products of HPs can cause oxidative reactivity. However, due to their unpleasant flavour, HPs make edible oils less attractive to consumers. Additionally, consuming oils and goods containing HP can provoke food hazards and cause a number of ailments in humans, including cancer and atherosclerosis [9]. Antioxidants, either natural or synthetic, can be added to postpone lipid oxidation, in addition to preserving the oil quality and for extending the product shelf life by guarding against rancidity. Aiming at shielding fatty foods against rancidity and discoloration, commercially available synthetic antioxidants such as tert-butylhydroquinone (TBHQ), butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT) are frequently utilized. Nevertheless, [PERSON] reported that these antioxidant dietary additives are linked to liver damage and carcinogenesis [10]. Therefore, it is crucial to find new natural antioxidants or to enhance the antioxidant activity of the natural compounds which already exist. Rosmary (_Rosmarius officinalis_ L.) is a unique spice that is commercially available for use in culinary, pharmacy, and cosmetics, acting as a strong antioxidant source [11]. Cyclic diterpene diphenols--rosmarinic acid (RA), carnosic acid (CA), and carnosol--have been reported as being among the most potent antioxidant components of rosmary extract [12]. CA is known as the most prevalent and is a potent natural antioxidant [13]. CA is a natural phenolic compound, containing the phenolic hydroxyl group. Numerous studies have documented how polyphenols prevent lipid oxidation [14; 15]. In comparison with the more commonly used synthetic antioxidants BHT and BHA in sunflower oil, soybean oil, and bulk corn oil, CA was shown to have a better antioxidative activity [16]. It has been demonstrated that CA effectively reduces the development of HPs of particular fatty acids [17]. Additionally, CA is crucial for the pharmacological actions against inflammatory disorders, diabetes, cancer, and cardiovascular diseases [18]. However, due to the presence of several ring structures and a polar nature of phenolics, they are poorly soluble in fatty matrix, exhibiting a low processing stability [19]. As a result, phenolic compounds are less effective in preventing the lipid oxidation and related deterioration of oils and fats [20]. Vesicular carriers such as lecithin-based systems for polyphenols delivery (mainly the liposomes) are frequently used in different aqueous systems [19]. The lecithin, a co-enrichment substance that may improve the stability of polyunsaturated oils, can also increase the solubility of phenolics in oils [20]. To the best of our knowledge, the effect of rosmary extract on the oxidation stability of Aoil was not studied.