Analysis of Lipids in Pitaya Seed Oil by Ultra-Performance Liquid Chromatography-Time-of-Flight Tandem Mass Spectrometry.

Red pitaya (Hylocereus undatus) is an essential tropical fruit in China. To make more rational use of its processing, byproducts and fruit seeds, and the type, composition, and relative content of lipids in pitaya seed oil were analyzed by UPLC-TOF-MS/MS. The results showed that the main fatty acids in pitaya seed oil were linoleic acid 42.78%, oleic acid 27.29%, and palmitic acid 16.66%. The ratio of saturated fatty acids to unsaturated fatty acids to polyunsaturated fatty acids was close to 1:1.32:1.75. The mass spectrum behavior and fracture mechanism of four lipid components, TG 54:5|TG 18:1_18:2_18:2, were analyzed. In addition, lipids are an essential indicator for evaluating the quality of oils and fats, and 152 lipids were isolated and identified from pitaya seed oil for the first time, including 136 glycerides and 16 phospholipids. The main components of glyceride and phospholipids were triglycerides and phosphatidyl ethanol, providing essential data support for pitaya seed processing and functional product development.

Effects of four drying methods on Amomum villosum Lour. 'Guiyan1' volatile organic compounds analyzed via headspace solid phase microextraction and gas chromatography-mass spectrometry coupled with OPLS-DA.

This paper analyzed the effects of four drying methods (heat pump drying, hot air drying, sun drying, and freeze drying) on the volatile organic compounds (VOCs) in fresh 'Guiyan1' Amomum villosum Lour. Via separation, component differentiation, and overall variance analysis via HS-SPME-GC/MS coupled with OPLS-DA, 133 kinds of VOCs, mainly composed of hydrocarbons, esters, and alcohols, were identified. The differences in 'Guiyan1' processed by freeze-drying and the other three drying methods were the most significant and easily distinguishable. The main VOCs in the dried samples were bornyl acetate and 2-bornanone, with the largest increase in 2-bornanone and the largest decrease in bicyclogermacrene. The obtained data provided guidance for optimizing the processing and storage of 'Guiyan1'.

Identification of phenolics from miracle berry (Synsepalum dulcificum) leaf extract and its antiangiogenesis and anticancer activities.

Miracle berry is well-known for its ability to convert sour foods to sweet. In this study, the secondary metabolites of miracle berry leaves (MBL) were identified by UPLC-DAD-MS, and its antiangiogenesis and anticancer activities were evaluated by using a zebrafish model and the MCF-7 xenograft mouse model, respectively. The result showed that 18 phenolic compounds were identified in MBL extract, and dominated by the derivatives of quercetin and myricetin. The MBL extract showed low toxicity and high antiangiogenesis activity, it significantly inhibited the subintestinal vein vessels development in zebrafish at very low concentration. Furthermore, the MBL extract could promote the apoptosis of tumor cells and significantly inhibit the growth of MCF-7 xenograft tumor. In addition, the analysis of metabolites revealed that the MBL extract inhibited tumor growth by activating the metabolic pathways of unsaturated fatty acids and purines. Overall, this study suggests that MBL extract can be used as a natural anticancer adjuvant in the fields of functional foods.

A novel approach for authentication of shellac resin in the shellac-based edible coatings: Contain shellac or not in the fruit wax preservative coating.

As an edible coating substrate, the detection of shellac resin has always been an intractable problem. In this paper, an authentication method of shellac resin in shellac-based edible coatings was established. Results showed that the authentication of shellac resin could be skillfully transformed as the identification of 13 targeted metabolites which were monomer compounds of shellac resin. The 13 targeted metabolites were further divided into 6 differential metabolites and 7 common metabolites with the metabonomic method and difference analysis of targeted metabolite contents. Then, four commercial soi-disant shellac-based coating solutions were selected to verify the feasibility of this method, and 7 common metabolites were detected in only one commercial sample, highly consistent with the results of shellac resin. All the above results indicated that the targeted metabolomics approach established in this study could provide a scientific basis for the qualitative authentication of shellac resin in the preservation coating.

A Gas-Permeation Controllable Packaging Membrane with Porous Microspheres as Gas "Switches" for Efficient Preservation of Litchi.

Food wastage represented by the deterioration of perishable food like fruits and vegetables is a serious global problem with tremendous ethical, financial, and environmental costs. The atmosphere (CO2 and O2) has a crucial role in food storage and can regulate physiological food metabolism and microbial growth. Modified atmosphere packaging (MAP) is a promising method used to extend shelf life and preserve the quality of perishable food; yet, its use depends on the specific gas permeability and selectivity of polymer membranes to generate an atmosphere desirable for storage. In this study, we established and validated a new plant leaf-mimetic shellac-based MAP membrane embedded with chitosan porous microspheres loaded with antimicrobial tannic acid (TA-CPM) as gas "switches" for regulating O2 and CO2 permeability and CO2/O2 selectivity. The effects of different amounts of TA-CPM added into the hybrid membranes were examined for litchi preservation at room temperature. Our results showed that this hybrid TA-CPM/shellac packaging membrane could regulate the internal CO2 and O2 concentrations and the CO2/O2 ratio within the packages containing litchis by adjusting the addition amount of TA-CPM. The 0.05% TA-CPM/shellac and 0.10% TA-CPM/shellac packages, especially 0.05% TA-CPM/shellac, generated a more desirable CO2 and O2 atmosphere for litchi preservation compared with controls, which was reflected by the delaying of browning and rotting, maintaining of the natural color of the litchi pericarp, preservation of pulp quality, inhibition of polyphenol oxidase and guaiacol peroxidase activities, and reduction of oxidative cell damage in litchis. The results suggested that 0.05% TA-CPM/shellac and 0.10% TA-CPM/shellac packaging membranes, especially 0.05% TA-CPM/shellac, could generate an ideal atmosphere for litchi storage at room temperature, demonstrating that this permeation-controlled hybrid membrane has great potential in food preservation and other applications requiring a modified atmosphere.

A Plant Leaf-Mimetic Membrane with Controllable Gas Permeation for Efficient Preservation of Perishable Products.

About one-third of the world's food is lost and wasted each year, along with excessive carbon emission, disposals, and other environmental issues. The rotting of perishable products like fruits and vegetables accounts for the largest percentage of food waste due to their short shelf life. The storage atmosphere (H2O, O2, CO2) acts as a key role in the preservation process and could regulate plants' physiological metabolism and microbial growth. In this work, a facile and biomimetic strategy is introduced for food preservation at room temperature employing PLLA (poly(l-lactic acid)) or chitosan porous microspheres as gas "switches" or "stomata" in a shellac membrane to regulate O2, CO2, and H2O permeability and CO2/O2 selectivity. Surface coatings on fruits or packaging films prepared through this strategy show exceptional preservation performance on five selected model fruits with different respiratory metabolisms. These hybrid materials could effectively control the gases (O2, CO2, and H2O) permeability and CO2/O2 selectivity by adding different amounts of porous microspheres or depositing small functional molecules, which demonstrate excellent antioxidant, antimicrobial, water-resistant, and reusable properties. This gas permeation control strategy has great potential in food preservation as well as other applications where a controlled atmosphere is required.

A comprehensive study of raw and roasted macadamia nuts: Lipid profile, physicochemical, nutritional, and sensory properties.

Macadamia nuts have high nutritional value and positive health attributes. Changes to the composition and availability of these compounds during roasting contribute to product quality. In this study, changes to the chemical composition of lipids (fatty acids, triglycerides, and free fatty acids) and other phytochemicals were analyzed, and a sensory evaluation was carried out of two major varieties of macadamia nuts planted in China, after roasting. Only small changes in fatty acid (FA) content and a slight decrease in total triglycerides (TAGs) were observed after roasting. The free fatty acid (FFA) content and the peroxide value were increased by roasting. The total available polyphenol content increased by 25.6% and the oxidative stability index of kernels increased by 21.6%. The sensory scores for taste and aroma were doubled by roasting. Overall, the sensory, nutritional quality, and oxidative stability of roasted macadamia nuts were greatly improved, compared with raw nuts.

Novel edible coating based on shellac and tannic acid for prolonging postharvest shelf life and improving overall quality of mango.

This study aimed to investigate the combined effects of a coating based on shellac and the active agent tannic acid (TA) on the storability and physiological variations of mangoes stored at room temperature. Results showed that TA-shellac prolonged shelf life and improved overall quality of mangoes to a higher extent compared with controls, which was reflected in the extension of shelf life for approximately 10 days, maintaining of tissue firmness and weight loss, slowing down of respiration rate, improvement of physical properties and chemical qualities, suppression of browning, reduction of lipid peroxidation, preservation of aromatic volatiles, and regulation of the related enzymes activities. Addition of TA to shellac coating also improved the antifungal effect of the formulation. The results suggest that a synergistic effect took place between TA and shellac, which demonstrates the high potential for shelf life extension and quality improvement of mangoes of this formulation.

Pseudotargeted Lipidomics Strategy Enabling Comprehensive Profiling and Precise Lipid Structural Elucidation of Polyunsaturated Lipid-Rich Echium Oil.

Echium oil has great nutritional value as a result of its high content of α-linolenic acid (ALA, 18:3ω-3) and stearidonic acid (SDA, 18:4ω-3). However, the comprehensive lipid profiling and exact structural characterization of bioactive polyunsaturated lipids in echium oil have not yet been obtained. In this study, we developed a novel pseudotargeted lipidomics strategy for comprehensive profiling and lipid structural elucidation of polyunsaturated lipid-rich echium oil. Our approach integrated untargeted lipidomics analysis with a targeted lipidomics strategy based on Paternò-Büchi (PB)-tandem mass spectrometry (MS/MS) using 2-acetylpyridine (2-AP) as the reaction reagent, allowing for high-coverage lipid profiling and simultaneous determination of C═C locations in triacylglycerols (TGs), diacylglycerols (DGs), free fatty acids (FFAs), and sterol esters (SEs) in echium oil. A total of 209 lipid species were profiled, among which 162 unsaturated lipids were identified with C═C location assignment and 42 groups of ω-3 and ω-6 C═C location isomers were discovered. In addition, relative isomer ratios of certain groups of lipid C═C location isomers were revealed. This pseudotargeted lipidomics strategy described in this study is expected to provide new insight into structural characterization of distinctive bioactive lipids in food.

Serumal Lipidomics Reveals the Anti-inflammatory Effect of Flax Lignans and Sinapic Acid in High-Fat-Diet-Fed Mice.

Flax lignans (SDG) and sinapic acid (SA) both have the function of antioxidation and anti-inflammation. However, previous studies have focused mainly on biochemical measurements, gene expression analysis, and clinical assessments. There are limited studies that systematically reveal the underlying mechanism of the anti-inflammation effect of SDG or SA from the lipidomic point of view. Herein, the integrated lipidomic profiling platform was used for the analysis of free fatty acids (FFAs), phospholipids (PLs), triacylglycerols (TAGs), and oxylipins in high-fat (HF)-diet-fed mice after SDG or SA administration. Dietary supplementation of SDG or SA downregulated the levels of total TAGs and FFAs in the ApoE-/- mice model. Furthermore, 28 potential lipids were screened out and considered as key evaluation factors to understand the anti-inflammation function and mechanism of SDG and SA. The results indicated that the anti-inflammatory effect of SDG and SA was principally exerted via regulation of lipid homeostasis.

Metabolite Profiling and Transcriptome Analyses Provide Insight Into Phenolic and Flavonoid Biosynthesis in the Nutshell of Macadamia Ternifolia.

Macadamia ternifolia is a dynamic oil-producing nut crop in the world. However, the nutshell is frequently considered as a low-quality material. Further, its metabolic profile is still uncharacterized. In order to explore the industrial significance of the nutshell, this study performed metabolic and transcriptomic analyses at various developmental stages of the nutshell. The qualitative and quantitative metabolic data analysis identified 596 metabolic substances including several species of phenolic acids, flavonoids, lipids, organic acids, amino acids and derivatives, nucleotides and derivatives, alkaloids, lignans, coumarins, terpenoids, tannins, and others. However, phenolic acids and flavonoids were predominant, and their abundance levels were significantly altered across various developmental stages of the nutshell. Comparative transcriptome analysis revealed that the expression patterns of phenolic acid and flavonoid pathway related genes were significantly changed during the nutshell growth. In particular, the expression of phenylalanine ammonia-lyase, C4H, 4CL, CHS, CHI, F3H, and FLS had dynamic differences at the various developmental stages of the nutshell. Our integrative metabolomic and transcriptomic analyses identified the key metabolic substances and their abundance levels. We further discussed the regulatory mechanism of phenolic and flavonoid biosynthesis in the nutshell of M. ternifolia. Our results provide new insights into the biological profiles of the nutshell of M. ternifolia and help to elucidate the molecular mechanisms of phenolic and flavonoid biosynthesis in the nutshell of M. ternifolia.

Formation Mechanism of Bleaching Damage for a Biopolymer: Differences between Sodium Hypochlorite and Hydrogen Peroxide Bleaching Methods for Shellac.

Bleached shellac, a widely used material in food processing and products, was deeply affected in terms of structures and properties by the bleaching method. In the present study, a marked difference was observed between the damage performances of sodium hypochlorite-bleached shellac (SHBS) and hydrogen peroxide-bleached shellac (HPBS). The main bleaching damage reactions of sodium hypochlorite were the addition of double bonds to generate chlorine and the oxidation of hydroxyl to form aldehydes or ketones. In the case of hydrogen peroxide, degradation of shellac resin was caused by the hydrolysis of ester bonds and the oxidation of hydroxyl groups to form aldehydes and ketones, as well as carboxylic acids with deep oxidation. Based on the structural characterization of shellac resin, the bleaching damages were affected by the bleaching agent via the oxidizable groups, such as the unsaturated double bonds, hydroxyl and aldehyde groups in cyclic terpenes, and fatty acid chains. The differences could be attributed to the action of sodium hypochlorite on the hydroxyl group of aldehyde or ketone. Conversely, hydrogen peroxide bleaching oxidized the hydroxyl group and aldehyde group to carboxylic acid and initiated the hydrolysis reaction of the ester bond of the shellac resin, leading to the degradation of the resin. Thus, understanding the mechanism underlying the bleaching damage could provide a scientific basis for the subsequent targeted regulation of bleaching damage.

Ultrasound-assisted one-phase solvent extraction coupled with liquid chromatography-quadrupole time-of-flight mass spectrometry for efficient profiling of egg yolk lipids.

In this research, a novel ultrasound-assisted extraction (USAE) method using a one-phase solvent (isopropanol, IPA) combined with liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QToF-MS) was developed for exhaustive profiling of egg yolk lipids, which are considered to be essential nutrients that have important functions for human health. Compared with IPA-vortex extraction method, the optimized IPA-USAE method shows better performance in terms of extraction time, lipid losses, lipid recoveries and the number of lipids identified. With this established simple, high throughput and reliable analytical approach, untargeted comprehensive lipid profiling of four kinds of egg yolks was achieved, thus providing a powerful tool for nutritional research of egg lipids. Considering that the lipids contained in egg yolk are quite abundant in both quantity and species, the proposed IPA-USAE combined with LC-ESI-QToF-MS is also potentially applicable to comprehensive extraction and profiling of lipids in other biological samples.