The structure of triglycerides impacts the digestibility and bioaccessibility of nutritional lipids during in vitro simulated digestion

Physicochemical characterization, bioactive compounds, and in vitro digestion characteristics of Moringa oleifera seed oil: a comprehensive investigation

BACKGROUND

Moringa oleifera is a wild plant belonging to the genus Moringa and the family Moringaceae, which possesses valuable nutritional and medicinal properties and is inexpensive. The present study aimed to provide a comprehensive assessment of the potential of M. oleifera seed oil (MoSO) as a food ingredient by investigating its physicochemical properties, bioactivity, and in vitro digestion characteristics.

RESULTS

The results revealed that MoSO exhibited a high oleic acid content, which constituted 72.06 ± 0.17% of the total fatty acid content. The oil consisted of ten primary triacylglycerols, with O-O-O (40.64 ± 0.41%), Do-O-O (17.22 ± 0.17%), O-O-P (14.92 ± 0.15%) and Eo-O-P (10.50 ± 0.10%) being the most abundant. It contained certain bioactive compounds, such as tocopherols (224.04 ± 1.78 mg/kg) and phytosterols (2155.65 ± 23.45 mg/kg). The in vitro digestion behavior of MoSO emulsion was also investigated. The maximum release of free fatty acids in MoSO was 90.14 ± 2.77%, surpassing that observed in soybean oil (85.62 ± 3.01%). Moringa oleifera seed oil also exhibited a substantial release of oleic acid and greater bioaccessibility.

CONCLUSION

These findings contribute to the current knowledge on MoSO as a promising candidate for a high-quality edible vegetable oil. © 2025 Society of Chemical Industry.

Medium- and long-chain triacylglycerols as enteral nutrition enhancing the nutritional status of postoperative rats undergoing chemotherapy by increasing the bioavailability of functional fatty acids

Medium- and long-chain triacylglycerols (MLCTs) have been widely used in the field of pharmaceutical nutrition. However, the application of MLCT as enteral nutrition remains underexplored. Our previous in vitro digestion experiment revealed that MLCTs can improve the bioaccessibility of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in comparison with physically mixed oils (MOs). In this study, we showed that MLCTs promote enhance triglyceride synthesis and secretion in Caco-2 cells, as evidenced by significant upregulation of RNA transcription levels of FATP4, L-FABP, and PPARα (p < 0.05) compared with MOs. Animal experiment results show that MLCTs can improve the energy metabolism and liver function, decrease NF-κB p65 and inflammatory cytokines, such as TNF-α, IL-6, and IL-8 of rats undergoing chemotherapy postoperatively. This was related to the elevated bioavailability and metabolic efficiency of functional fatty acids in MLCTs. Besides, RT-qPCR, western blot, and immunohistochemical analyses confirme that MLCTs downregulate the expression of proinflammatory factors by suppressing the liver NF-κB signal transduction pathway, thereby improving the nutritional status of rats.

Innovative applications of medium- and long-chain triacylglycerol in nutritional support: Current perspectives and future directions

As a unique structured lipid, medium- and long-chain triacylglycerol (MLCT) is characterized by the combination of medium- and long-chain fatty acids in a single triacylglycerol molecule. In recent years, MLCT, as a nutritional lipid, has gradually emerged as a research hot topic in the fields of food science and nutrition. This paper innovatively provides a comprehensive review of the current application status and development prospects of MLCT in nutritional support. First, the basic principles defining characteristics and selection basis of both enteral and parenteral nutrition are analyzed, elucidating the differences between the two modalities in terms of nutrient delivery pathway, absorption mechanisms, and physiological effects. Subsequently, the natural sources and artificial synthetic pathways of MLCT along with its metabolic behavior in vivo are elaborated. On this basis, the latest research advancements in the application of MLCT in both nutritional models are reviewed, with a particular emphasis on current research hotspots. Finally, the challenges encountered in the practical application of MLCT are discussed, and the future trajectory of MLCT as a functional lipid is predicted. In particular, the innovative potential of MLCT in functional foods, food for special medical purposes, personalized nutrition, and other aspects is emphasized, which provides beneficial ideas and directions for further research and industrial applications of MLCT.

A review on lipid inclusion in preterm formula: Characteristics, nutritional support, challenges, and future perspectives

The lack of nutrient accumulation during the last trimester and the physiological immaturity at birth make nutrition for preterm infants a significant challenge. Lipids are essential for preterm infant growth, neurodevelopment, immune function, and intestinal health. However, the inclusion of novel lipids in preterm formulas has rarely been discussed. This study discusses specific lipid recommendations for preterm infants according to authoritative legislation based on their physiological characteristics. The gaps in lipid composition, such as fatty acids, triacylglycerols, and complex lipids, between preterm formulas and human milk have been summarized. The focus of this study is mainly on the vital roles of lipids in nutritional support, including long-chain polyunsaturated fatty acids, structural lipids, milk fat global membrane ingredients, and other minor components. These lipids have potential applications in preterm formulas for improving lipid absorption, regulating lipid metabolism, and protecting against intestinal inflammation. The lipidome and microbiome can be used to provide adequately powered evidence of the effects of lipids. This study proposes nutritional strategies for preterm infants and suggests approaches to enhance their lipid quality in preterm formula.

Medium- and long-chain triacylglycerol has higher digestibility and bioaccessibility compared with physical mixed oils under conditions of bile salts secretion deficiency

Bile salts play a major role in intestinal lipid digestion. In this study, the effects of bile salts concentration on the digestive characteristics and bioaccessibility of two oils with the same fatty acid composition but different triacylglycerol structures, physical mixed oil (MO) and medium- and long- chain triacylglycerol (MLCT), were investigated under simulated gastrointestinal conditions. Results revealed that as the bile salt concentration increased from 0.0 mg/mL to 5.0 mg/mL, the free fatty acids (FFAs) release of both oils exhibited an increasing trend. MLCT presented higher free fatty acids release and more stable release rate. Furthermore, at a bile salt concentration of 5.0 mg/mL, the bioaccessibility of FAs in MLCT was significantly higher than that in MO, with respective values of 79.51 ± 1.19 % and 74.69 ± 1.02 % (p < 0.05). Notably, even in conditions of bile salts deficiency, especially at a bile salt concentration of 1.0 mg/mL, the bioaccessibility of FAs in MLCT remained superior to that in MO, reaching levels of 43.29 ± 0.89 % and 46.47 ± 1.31 %, respectively, with statistical significance (p < 0.05). Theses findings further demonstrated that MLCT exhibits superior digestion characteristics. This study provided a scientific basis for the selection of nutritional lipids in clinical nutrition support.

Assembly complexes of egg yolk low-density lipoprotein and Auricularia auricula polysaccharide stabilized high internal phase Pickering emulsions: Insights into the stabilization mechanism via fluid-fluid interaction between water and oil phases

The interfacial stabilization mechanisms have been thoroughly researched in high internal phase Pickering emulsion (HIPPE), yet the role of fluid-fluid interaction between the water and oil phases at the interfaces in determining HIPPE stability has attracted comparatively less attention. Thus, this study adopted an assembly strategy to prepare egg yolk low-density lipoprotein (LDL) complexes with Auricularia auricula polysaccharide (AAP), aiming to enhance the functionality while regulating the fluid-fluid interaction strength at the oil-water interface by tuning the proteoglycan ratio to modulate HIPPE stability. AAP was assembled with LDL via hydrogen bonding and electrostatic interactions, with a higher protein ratio enhancing these intermolecular interactions. According to the Raman spectroscopy, stronger fluid-fluid interactions were observed with increasing protein concentrations. AAP-LDL assembly complexes provided superior physical stability to HIPPE than that of LDL. HIPPE stabilized by the assembly complexes successfully delivered quercetin and enhanced lipid digestion. This research augments the HIPPE stability theoretical system and contributes to the improved physical stability of HIPPE-based functional foods in industrial applications.

Oxidative Lipidomics to Unravel the Glycerol Core Aldehydes of Three Typical Unsaturated Triglycerides under Simulated Heating Conditions

Glycerol core aldehydes (GCAs) are significant nonvolatile aldehyde compounds generated in heated edible oils, which may pose potential health risks. Utilizing the complementary CID and EAD mass spectrometry data, this study introduced a predict-to-hit strategy, identifying 42 types of GCAs from oxidized OOO, LLL, and LnLnLn. Structural analysis revealed that oxidation occurred at both the sn-2 and sn-1/3 positions of triglyceride (TG), with the Sn-1/3 position exhibiting greater susceptibility as the degree of TG unsaturation increased. As the temperature increases, the concentration of saturated GCAs steadily rises, while unsaturated GCAs exhibit an initial increase, followed by a decrease. During further oxidation, GCAs tend to convert into hydroxyl compounds, monocyclic epoxides, dicyclic epoxides, and polycyclic epoxides, with epoxy groups predominantly forming at the 9,10 positions. These observations enhance our understanding of the formation of GCAs and promote the search for strategies to delay or prevent oxidation.

In Vitro Lipid Digestion of Milk Formula with Different Lipid Droplets: A Study on the Gastric Digestion Emulsion Structure and Lipid Release Pattern

In this study, the digestive properties of milk formulas (two concept milk formulas L1 and L2 with D4,3 ∼5 μm and a control milk formula S1 with D4,3 ∼0.5 μm) were evaluated using a dynamic digestion model simulating the infant gastrointestinal tract. The results showed that L1 and L2 had a lower lipolysis degree compared to S1 during gastric digestion and no significant difference at the end of the digestion process. Triacylglycerol lipolysis products were highly related to the lipid sources of milk formulas. At the end of digestion, glycerophospholipids in milk formulas were hydrolyzed to lysophospholipids (∼60-80%), while sphingomyelins were barely hydrolyzed. Concept milk formulas showed a complete spherical structure with a mean size of 3-5 μm during gastric digestion, while the control formula had large aggregates consisting of small lipid droplets. This study reveals that the structure of lipid droplets moderates the gastric digestion emulsion structure and further influences the digestive properties of milk formulas.

Novel high internal phase emulsion gels stabilized solely by hemp protein isolate: Enhancement of cannabidiol chemical stability and bioaccessibility

This study aims to fabricate high internal phase emulsion gels (HIPEGs) using modified hemp protein isolates for microencapsulating cannabidiol (CBD) to enhance their chemical stability and bioaccessibility. Importantly, the combined effect of CBD concentrations (0.1 vs 0.5 wt%) and post gel storage conditions (before-refrigeration (BR) vs after-refrigeration (AR)) on the properties of HIPEGs were investigated. The results showed that the CBD concentration above 0.4 % is necessary to fabricate a stable HIPEG. The rheological properties of HIPEGs were influenced by CBD concentration and refrigeration. The AR gels with 0.5 % CBD showed the highest gel strength (up to 91.7 Pa) and solid-like structures. These properties allowed to HIPEGs maintain good physical stability during storage at 4, 25, and 37 °C for 14 days due to the interconnected polyhedral protein matrices and thick interfacial protein layers. These unique protein architectures offered superior protection against CBD degradation (<2 % of initial added amount) for 100 days during exposure to light and temperature (25 or 37 °C). The INFOGEST digestion results showed the BR gels effectively protected CBD during digestion and consequently improved their stability and bioaccessibility up to 95 % and 74 %, respectively. Overall, the fabricated HIPEGs could be valuable for nutraceutical delivery.

Human milk fat substitutes rich in 1,3-dioleoyl-2-palmitoylglycerol and 1-oleoyl-2-palmitoyl-3-linoleoylglycerol simultaneously: Preparation strategy and simulated infant in vitro digestion

In this study, fractionated palm stearin, oleic acid, and linoleic acid were selected as the base materials to prepare human milk fat substitutes (HMFS) rich in OPO and OPL by enzymatic acidolysis combined with physical blending. Under optimum conditions, contents of OPO, OPL, and sn-2 palmitic acid in the OPO and OPL-rich triacylglycerols (TAGs) were higher than that in commercial OPO-rich TAGs, with values of 37.25%, 28.12%, and 79.44%, respectively. Physical blending the OPO and OPL-rich TAGs (47%), bovine milk fat (18%), sunflower oil (13%), coconut oil (13%), corn oil (8%), and palm oil (1%) can obtain HMFS with a fat composition that like HMF. The fatty acid, sn-2 saturated fatty acid, and TAG contents of HMFS were within the lower and upper limit of HMF. The lipolysis degree of infant formula (IF) with HMFS as fat source is 9.0% higher than that of commercial plant oil-based infant formula (PIF), and 3.4% lower than that of human milk. IF with HMFS as fat source released less saturated free fatty acids and more saturated monoacylglycerols during digestion than that of PIF, which would help improve the IF fat utilization by infants.

Functional foods lipids: unraveling their role in the immune response in obesity

Functional lipids are lipids that are found in food matrices and play an important role in influencing human health as their role goes beyond energy storage and structural components. Ongoing research into functional lipids has highlighted their potential to modulate immune responses and other mechanisms associated with obesity, along with its comorbidities. These lipids represent a new field that may offer new therapeutic and preventive strategies for these diseases by understanding their contribution to health. In this review, we discussed in-depth the potential food sources of functional lipids and their reported potential benefit of the major lipid classification: based on their composition such as simple, compound, and derived lipids, and based on their function such as storage and structural, by investigating the intricate mechanisms through which these lipids interact in the human body. We summarize the key insights into the bioaccessibility and bioavailability of the most studied functional lipids. Furthermore, we review the main immunomodulatory mechanisms reported in the literature in the past years. Finally, we discuss the perspectives and challenges faced in the food industry related to functional lipids.

Role of FXR in the development of NAFLD and intervention strategies of small molecules

Non-alcoholic fatty liver disease (NAFLD) remains a prevailing etiological agent behind hepatocyte diseases like chronic liver disease. The spectrum of processes involved in NAFLD stages includes hepatic steatosis, non-alcoholic fatty liver, and non-alcoholic steatohepatitis (NASH). Without intervention, the progression of NASH can further deteriorate into cirrhosis and ultimately, hepatocellular carcinoma. The cardinal features that characterize NAFLD are insulin resistance, lipogenesis, oxidative stress and inflammation, extracellular matrix deposition and fibrosis. Due to its complex pathogenesis, existing pharmaceutical agents fail to take a curative or ameliorative effect on NAFLD. Consequently, it is imperative to identify novel therapeutic targets and strategies for NAFLD, ideally to improve the aforementioned key features in patients. As an enterohepatic regulator of bile acid homeostasis, lipid metabolism, and inflammation, FarnesoidX receptor (FXR) is an important pharmacological target for the treatment of NAFLD. Manipulating FXR to regulate lipid metabolic signaling pathways is a potential mechanism to mitigate NAFLD. Therefore, elucidating the modulatory character of FXR in regulating lipid metabolism in NAFLD has the potential to yield groundbreaking perspectives for drug design. This review details recent advances in the regulation of lipid depletion in hepatocytes and investigates the pivotal function of FXR in the progress of NAFLD.

Medium- and Long-Chain Triacylglycerol: Preparation, Health Benefits, and Food Utilization

Medium- and long-chain triacylglycerol (MLCT) is a structured lipid with both medium- and long-chain fatty acids in one triacylglycerol molecule. Compared with long-chain triacylglycerol (LCT), which is mainly present in common edible oils, and the physical blend of medium-chain triacylglycerol with LCT (MCT/LCT), MLCT has different physicochemical properties, metabolic characteristics, and nutritional values. In this article, the recent advances in the use of MLCT in food formulations are reviewed. The natural sources and preparation of MLCT are discussed. A comprehensive summary of MLCT digestion, absorption, transport, and oxidation is provided as well as its health benefits, including reducing the risk of overweight, hypolipidemic and hypoglycemic effects, etc. The potential MLCT uses in food formulations, such as infant formulas, healthy foods for weight loss, and sports foods, are summarized. Finally, the current safety assessment and regulatory status of MLCT in food formulations are reviewed.

Bioaccessibility of docosahexaenoic acid in naturally and artificially enriched milk

This study aimed to compare the bioaccessibility of docosahexaenoic acid (DHA) in naturally and artificially enriched milk and investigate the potential mechanisms involved. The results indicated that the DHA in naturally enriched milk (NEM) had a higher bioaccessibility (76.9 %) and a lower digestive loss rate (18.1 %) compared to artificially enriched milk (ArEM). Moreover, NEM contained a higher proportion of DHA-containing glycerophospholipids and sn-2 DHA, with fewer long-chain fatty acids and more saturated fatty acids adjacent to DHA in the same lipid molecule. During simulated intestinal digestion, NEM had a higher free fatty acid release and lipid digestion rate than ArEM. These findings suggested that the bioaccessibility of endogenous DHA in milk was superior to that of externally added DHA due to its more easily digestible and absorbable chemical binding form and lower digestive loss rate. The easy digestibility of milk lipids in NEM also contributed to its high DHA bioaccessibility.

A lipase-conjugated carbon nanotube fiber-optic SPR sensor for sensitive and specific detection of tributyrin

As a low-density lipoprotein, tributyrin plays an essential role in food safety and human health. In this study, a novel lipase-conjugated carbon nanotube (CNT) surface plasmon resonance (SPR) fiber-optic sensor is used to specifically detect tributyrin for the first time. In this work, CNTs can be used as an amplifying material to significantly increase the sensitivity of SPR sensors due to their high refractive index and large surface area. CNTs can also be used as an enzyme carrier to provide abundant carboxyl groups for the specific binding of lipases. Covering the surface of the sensor with CNTs can not only enhance the performance of the sensor, but also provide sufficient detection sites for subsequent biomass detection, reduce the functionalization steps, and simplify the sensor preparation process. The experimental results demonstrate that the refractive index sensitivity of the traditional multimode fiber (MMF)-single mode fiber (SMF)-MMF transmissive optical fiber sensor is 1705 nm RIU-1. After covering the sensor with CNTs, the sensitivity is 2077 nm RIU-1, and the sensitivity has been improved very well. In addition, there are abundant functional groups on CNTs, which can provide abundant binding sites. Conjugating lipase on carbon nanotubes helps to achieve linear detection in the range of 0.5 mM to 4 mM tributyrin, with a sensitivity of 4.45 nm mM-1 and a detection limit of 0.34 mM, which is below the 2.26 mM detection standard and meets food safety monitoring requirements. Compared with other sensors, the optical fiber biosensor proposed in this study expands the concentration detection range of tributyrin. Furthermore, the sensor also has good stability, anti-interference performance and specificity. Therefore, the sensor proposed in this paper has good application prospects in the fields of food safety and biomedicine.