In-vitro bio-accessibility and antioxidant activity of commercial standard and enriched whole egg compounds influenced by production and domestic cooking practices

Commercial whole eggs can be enriched to deliver health-beneficial compounds such as lutein and polyunsaturated fatty acids (PUFA). The combined effect of domestic cooking and gastrointestinal (GI) digestion on enriched egg bio-accessibility and biological activity must be fully elucidated. Thus, this study determines how the combined factors modulate whole egg bio-accessibility and antioxidant activity. Eggs from local supermarkets were cooked and subjected to in vitro GI digestion. The eggs and hydrolysates were characterized for their degree of hydrolysis (DH), carotenoid, PUFA, peptide content, and antioxidant activity. The cooking and digestion influence the DH and carotenoids, whereas PUFA and peptide contents remain unaffected. There was no difference in the antioxidant capacity between the different types of eggs. This study introduces a holistic approach to understanding how production and domestic cooking conditions modulate the bio-accessibility and bioactivity of eggs, which could be used to maximize the health benefits of eggs to consumers.

Ethnopharmacology of Rubus idaeus Linnaeus: A critical review on ethnobotany, processing methods, phytochemicals, pharmacology and quality control

ETHNOPHARMACOLOGICAL RELEVANCE

Rubus idaeus Linnaeus (RI) is a Chinese herbal medicine that has been widely used in China for a long time to reinforce the kidney, nourish the liver, improve vision, and arrest polyuria.

AIM OF THE STUDY

This work aims to evaluate the recent progress of the chemical composition, pharmacological activity, pharmacokinetics, metabolism, and quality control and of Rubus idaeus, which focuses on the insufficiency of existing research and will shed light on future studies of Rubus idaeus.

METHODS

Literatures about "Rubus idaeus","Red raspberry" and "Fupenzi"are retrieved by browsing the database, such as Web of Science (http://www.webofknowledge.com/wos), Pubmed (https://pubmed.ncbi.nlm.nih.gov/), CNKI (http://www.cnki.net/), and Wanfang Data (http://www.wanfangdata.com.cn). In addition, related textbooks and digital documents are interrogated to provide a holistic and critical review of the topic. The period of the literature covered from 1981 to 2022.

RESULTS

Approximately 194 compounds have been isolated from Rubus idaeus, which is rich in phenols, terpenoids, alkaloids, steroids, and fatty acids. Numerous investigations have demonstrated that Rubus idaeus exhibits many pharmacological activities, including hypoglycemic and hypolipidemic, anti-Alzheimer effect, anti-osteoporosis, hepatoprotective, anti-cancer, neuroprotective, anti-bacteria and skin care, etc. However, it is worth noting that most of the research is not associated with the conventional effect, such as reducing urination and treating opacity of the cornea.

CONCLUSION

The effectiveness of Rubus idaeus has been proved by its long-term clinical application. The research on the pharmacological activity of Rubus idaeus has flourished. In many pharmacological experiments, only the high-dose group can achieve the corresponding efficacy, so the efficacy of Rubus idaeus needs to be further interrogated. Meanwhile, the relationship between pharmacological activity and specific compounds of Rubus idaeus has not been clarified yet. Last but not least, studies involving toxicology and pharmacokinetics are very limited. Knowledge of bioavailability and toxicological behavior of Rubus idaeus can help understand the herb's pharmacodynamic and safety profile.

Thermal oxidation stability of different multi-element oleogels via 1H NMR spectroscopy

In this study, ¹H nuclear magnetic resonance was used to track the evolution of oxidation products of different multi-element oleogels (DMEOs) during temperature-accelerated oxidative degradation. The nutritional properties of the DMEOs were also indirectly explored. Oleogels prepared using sitosterol/lecithin oleogelator showed higher nutritional properties than those prepared using carnauba wax or ethyl cellulose oleogelators. Only a small amount of primary oxidation product hydroxide, (Z,E)-conjugated dienic systems, and (E,E)-conjugated dienic systems were produced from all oleogels upon accelerated oxidation. Furthermore, no ¹H signal peaks of secondary oxidation products, such as aldehydes or ketones, were detected. However, very small amounts of primary alcohols (-CH₂OH-), secondary alcohols (-CHOH-), and epoxides were identified. Moreover, resveratrol loading and surfactant addition effectively stabilized the internal structure and unsaturated fatty acid acyl content of the oleogels.

Evaluating the effect of cooking and gastrointestinal digestion in modulating the bio-accessibility of different bioactive compounds of eggs

Eggs' nutritional value has been enhanced by enriching hen's diet with bioactive compounds, but factors influencing bio-accessibility are unspecified. This study investigated the effect of hen breed, diet enrichment, and cooking methods in modulating the egg compounds' bio-accessibility after gastrointestinal (GI) digestion. White Leghorn (WLH) and Rhode Island Red (RIR) hens were fed a corn-soybean-based diet enriched with flaxseed and carotenoids; eggs were collected, cooked, and subjected to simulated GI digestion. The results showed that egg proteins were equally digestible with no change in the degree of hydrolysis (DH). The linolenic fatty acid in enriched-cooked samples remained bio-accessible after GI digestion. The lutein bio-accessibility in enriched eggs decreased after GI digestion except in RIR fried sample. Eggs from WLH and RIR achieved similar peptide content after GI digestion. These results elucidate the bio-accessibility of different bioactive compounds in cooked eggs and the use of eggs as potential functional foods.

Changes in stability, tocopherols, fatty acids and antioxidant capacity of sacha inchi (Plukenetia volubilis) oil during French fries deep-frying

Sacha inchi (Plukenetia volubilis) oil (SI) is appreciated for its nutritional and sensorial characteristics. The aim of this study was to evaluate SI changes during French fries deep-frying at 170 °C or 180 °C up to 119 and 50 min, respectively; commercial soybean oil (SO) was tested as control. SI had high α-linolenic acid (53.8%), linoleic acid (33.4%) and total tocopherols (2540.1 mg/kg). During frying tocopherol content, oil stability and antioxidant capacity (ABTS, DPPH) decreased following zero-order kinetics; γ-tocopherol showed the strongest decrease. Notwithstanding the high SI unsaturation and the commercial antioxidant (TBHQ) in SO, SI showed slightly higher or similar hydrolysis (free fatty acids and diacylglycerols), similar primary (K₂₃₂, oxidized-triacylglycerols) and lower secondary (K₂₆₈, triacylglycerol oligopolymers) oxidation. Because of the high tocopherol content, SI showed lower degradation than SO. Thus, SI is suitable for short-term deep-frying; additionally, it may enhance the nutritional value and the flavour of fried foods.

Bioactive components of ethnomedicine Eerdun Wurile regulate the transcription of pro-inflammatory cytokines in microglia

ETHNOPHARMACOLOGICAL RELEVANCE

The traditional Mongolian medicine Eerdun Wurile (EW) has remarkable neural recovery effect, and has been playing a key role in the clinical treatment of neurological disorders including ischemic stroke in Inner Mongolia Autonomous Region of China. The preliminary pharmacological studies in animal suggested that EW regulates the expression of trophic factors in brain lesion and may also balance the polarization of activated microglia (Gaowa et al., 2018).

AIM OF THE STUDY

The pool of leading bioactive chemicals underlying the therapeutic effects of EW has not been identified. Therefore, the mechanism of action of EW is poorly understood. This study was aimed to identify the major group of compounds that contribute to the inhibition of neuroinflammation during stroke recovery through regulation of microglia polarization.

MATERIALS AND METHODS

The extracts of EW in different solvents were evaluated for their inhibitory ability of cytokine (IP-10) expression in LPS stimulated BV2 cells. The most effective extract (of petroleum ether extract) was further separated to 18 fractionations on a semi-preparative HPLC column, which were assess for the IP-10 down-regulation efficiency by RT-qPCR. The potent isolate was further fractionated in 12 fractions, which showed fewer peaks. The fraction 6 from this isolates, which remarkably down-regulates cytokines expression including IP-10, TNFα and IL-1β, was analyzed on UPLC-qTOF MS. The key chemicals were measured for their cytokine inhibition in BV2 cells and mouse primary microglia.

RESULTS

After two consecutive fractionating by preparative HPLC, petroleum ether extraction of EW gave 12 fractions with relatively distinctive chromatograms. A particular fraction (fraction 6) preserved the inhibitory effects on expression of pro-inflammatory cytokines including IP-10, TNFα, IL-1β and iNOS. The result of UPLC-qTOF MS analysis showed that the fraction contains 21 chemicals including costunolide, alantolactone, myristicin and linolenic acid, which significantly down-regulate the expression of key pro-inflammatory cytokines in LPS stimulated BV2 cells as well as mouse primary microglia.

CONCLUSION

Collectively our data suggest that the bioactive chemical pool which is responsible for the therapeutic effects of EW can be extracted in petroleum ether, and fractionated to a relatively small multiple components. Such components include known anti-inflammatory chemicals, which may contribute to the possible microglia polarization in brain lesion during the recovery of ischemic stroke.

Effect of adding alpha-tocopherol on the oxidation advance during in vitro gastrointestinal digestion of sunflower and flaxseed oils

Few in vitro studies have tackled the effect of alpha-tocopherol on lipid oxidation during digestion, and discrepant results have been reported. As a result, the aim of this study was to elucidate whether the addition of alpha-tocopherol enhances or slows down the advance of oxidation that occurs during in vitro gastrointestinal digestion of polyunsaturated lipids. For this purpose, commercial sunflower and flaxseed oils (as models of omega-6 and omega-3 rich lipid systems, respectively) were in vitro digested in the absence or in the presence of this tocol at different concentrations (0.02%, 0.2% and 2%). Proton Nuclear Magnetic Resonance (¹H NMR) and Solid Phase Microextraction followed by Gas Chromatography/Mass Spectrometry (SPME-GC/MS) were used to investigate in detail potential differences among the digests regarding lipolysis and oxidation level. Alpha-tocopherol addition did not affect the advance of lipolysis, whereas lipid oxidation was enhanced in a dose-dependent manner. In this regard, the increased degradation of polyunsaturated lipids and greater generation of primary and secondary oxidation products observed at higher concentrations of alpha-tocopherol confirmed this observation. Among the formed oxidation products, hydroperoxy-, hydroxy- and keto-dienes, as well as oxygenated alpha,beta-unsaturated aldehydes are worth mentioning. The in vitro bioaccessibility of added tocopherol was estimated to be very low, suggesting a notable transformation under the assayed conditions. Further in vivo studies are necessary to confirm this prooxidant activity of alpha-tocopherol during gastrointestinal digestion.

Volatile molecular markers of VOO Thermo-oxidation: Effect of heating processes, macronutrients composition, and olive ripeness on the new emitted aldehydic compounds

Heating operation has been applied to Chétoui extra-virgin olive oils (EVOOs) extracted from fruits with several ripening stages (RS). The studied samples, were subjected to microwave and conventional heating. Results showed that heated VOOs after 2.5 h and 7 min of conventional and microwave heating, respectively, gave rise to a drastically decrease of LOX products and allowed the detection of toxic new formed aldehydic volatiles (alkanal: nonanal, alkenals: (Z)-2-heptenal and (E)-2-decenal, and alkadienals: (E.E)-2.4-decadienal), which can be used as markers of VOO degradation. Their abundance in the VOO headspaces depends on their boiling points, the rate of their possible degradation to yield other compounds, on the heating processes and on the rate of macronutrients. The emission rate of the new synthesized volatiles during heating processes was mainly attributed to enzymatic oxidation of some fatty acids. Hexanal, (Z)-2-heptenal, (E)-2-octenal, (E)-2-nonenal, (E,E) and (E,Z)-2,4-decadienal, and (E,E)-2,4-nonadienal, derived from linoleic acid, and heptanol, octanal, nonanal, decanal, (E) and (Z)-2-decenal, (E)-2-undecenal, and (E,E)-2,4-nonadienal, are emitted after degradation of oleic acid. During thermo-oxidation, the ECN₄₄ (LLO, and OLnO), and the ECN₄₆ (OLO, and PLO + SLL) compounds decreased, whereas, the ECN₄₈ (OOO, and PPO), and the ECN₅₀ (SOO) compounds increased when temperature and heating time increased. The several variations of the studied biochemical compounds depend to the heating processes. Ripening stage of olive fruits can be used as a tool to monitor the emission rate of the aldehydic volatiles, but cannot be used for a chemometric discrimination.

Current state of knowledge on the traditional uses, phytochemistry, and pharmacology of the genus Hymenaea

ETHNOPHARMACOLOGICAL RELEVANCE

Plants of the genus Hymenaea (Fabaceae) are used in South American and Asian traditional medicines to treat a multitude of disorders, like cough, diarrhea, dysentery, intestinal colic, pulmonary weakness, asthma, anemia, sore throat, and for the treatment of kidney problems, viral related disorders, chronic cystitis, bronchitis, and bladder infections. Some Hymenaea species are also used as vermifuge, and for the treatment of arthritis, and inflammation conditions. This review deals with updated information on the traditional uses, phytochemistry and pharmacology of ethnomedicinally important Hymenaea species in order to provide an input for the future research prospects.

METHODS

Literature available in various recognized databases including Google Scholar, PubMed, SciFinder, Scopus, Springer, Wiley, ACS, Scielo and Web of Science, as well as from theses, dissertations, books, reports, and other relevant websites (www.theplantlist.org), are surveyed, analysed, and included in this review. Herein, the literature related to chemical constituents and pharmacological activities were searched in November 2016.

RESULTS

The literature provided information on ethnopharmacological uses of the South American and African species of the genus Hymenaea (e.g., H. courbaril, H. stigonocarpa, H. onblogifolia, H. martiana, H. parvifolia (South America) and H. verrucosa (African species)) for the treatment of multi-factorial diseases. From these plant species, more than 130 compounds, including fatty acids, flavonoids, terpenoids and steroids, phthalides, phenolic acids, procyanidins and coumarins were identified. Experimental evidences confirmed that the Hymenaea spp. could be used in treating inflammatory disorders, asthma, diarrhea, and some microbial infections. However, reports on the toxicity of Hymenaea species remain scarce.

CONCLUSION

Plants of this genus have offered bioactive samples, both from crude extracts and pure compounds, thus substantiating their effectiveness in traditional medicine. However, intensive investigations of all the species of Hymenaea spp. relating to phytochemical and pharmacological properties, especially their mechanism of action, safety and efficacy could be the future introspection.

Effect of traditional Chinese cooking methods on fatty acid profiles of vegetable oils

The effect of four frying processes (vegetable salad, stir frying, pan frying, and deep frying) on fatty acid composition of ten vegetable oils (peanut oil, soybean oil, rapeseed oil, corn oil, sunflower seed oil, rice bran oil, olive oil, sesame oil, linseed oil, and peony seed oil) was investigated using GC-MS. The result showed that trans-fatty acid (TFA) was produced during all processes. Rapeseed oil had the highest TFA content in vegetable salad oil with 2.88% of total fatty acid. The TFA content of sunflower seed oil was 0.00% in vegetable salad oil, however, after stir frying and pan frying, it increased to 1.53% and 1.29%, respectively. Peanut oil had the lowest TFA content after deep frying for 12h with 0.74mg/g. It was concluded that a healthy cooking process could be acquired by a scientific collocation.

Model studies on the formation of volatile compounds generated by a thermal treatment of steryl esters with different fatty acid moieties

The consumption of plant sterols is reported to have a beneficial effects on human health, i.e. phytosterols are known for their cholesterol-lowering properties. Whereas, they are prone to oxidation and currently there is ongoing worldwide research aimed at the biological effect of phytosterol oxides. In this study volatile compounds formed during thermal degradation of stigmasteryl esters were identified. The research was conducted using standards of stigmasterol, fatty acids and stigmasteryl esters as well as fat enriched with stigmasteryl esters which were thermally treated at 60°C and 180°C for 12h. Volatile compounds were characterised by SPME-GC-MS. Among the volatiles formed during heating of stigmasteryl esters aldehydes, ketones, alcohols and hydrocarbons were found. The mechanism of the formation of volatile compounds from sterol esters was related to oxidation of steryl and fatty acid moieties. In particular, 2-methyl-3-pentanone and 5-ethyl-6-methyl-3-hepten-2-one were identified as unique degradation products formed from degradation of the steryl moiety specifically, and a mechanism of their formation was suggested. Both volatiles could be a good indicator of thermo-oxidative degradation of functional food products enriched in phytosterols and their esters.

Flavor characteristic analysis of soymilk prepared by different soybean cultivars and establishment of evaluation method of soybean cultivars suitable for soymilk processing

Flavor is an essential quality characteristics of soymilk, which contains volatile compounds derived from fatty acids via enzymatic and thermal reactions. In this study, 67 kinds of soybean cultivars were selected, and correlation analysis was conducted between physicochemical indexes of these soybean cultivars and flavor characteristic indexes of soymilk. With clustering analysis, all the soybean cultivars could be classified into three classes, and according to the results of principal component analysis for each class of soymilk flavor characteristics, the soymilk of second class had relatively heavier beany and non-beany flavor, and the third class had weaker flavor. For soybean cultivars of which the soymilk characteristics were unknown, two discriminant functions could be used to predict flavor characteristics if the physicochemical indexes were known. Therefore, screening of soybean cultivars suitable for soymilk processing can be targeted for the flavor favored by consumers and an evaluation method established.

Lipid droplets in activated mast cells - a significant source of triglyceride-derived arachidonic acid for eicosanoid production

Mast cells are potent effectors of immune reactions and key players in various inflammatory diseases such as atherosclerosis, asthma, and rheumatoid arthritis. The cellular defense response of mast cells represents a unique and powerful system, where external signals can trigger cell activation resulting in a stimulus-specific and highly coordinated release of a plethora of bioactive mediators. The arsenal of mediators encompasses preformed molecules stored in cytoplasmic secretory granules, as well as newly synthesized proteinaceous and lipid mediators. The release of mediators occurs in strict chronological order and requires proper coordination between the endomembrane system and various enzymatic machineries. For the generation of lipid mediators, cytoplasmic lipid droplets have been shown to function as a major intracellular pool of arachidonic acid, the precursor for eicosanoid biosynthesis. Recent studies have revealed that not only phospholipids in mast cell membranes, but also triglycerides in mast cell lipid droplets are a substrate source for eicosanoid formation. The present review summarizes current knowledge about mast cell lipid droplet biology, and discusses expansions and challenges of traditional mechanistic models for eicosanoid production.

Effect of the refining process on Moringa oleifera seed oil quality

We evaluated the physicochemical properties and oxidative stability of the oil extracted from the seeds of Moringa oleifera during its refining process. Refining is accomplished in three stages: neutralization, degumming, and bleaching. Four samples were analyzed, corresponding to each step of the processed and crude oil. Increases in the density, viscosity, saponification value and oxidation of the oil were detected during the refining, while the peroxide value and carotenoid content diminished. Moreover, the refractive index and iodine content were stable throughout the refining. Nine fatty acids were detected in all four samples, and there were no significant differences in their composition. Oleic acid was found in the largest amount, followed by palmitic acid and behenic acid. The crude, neutralized, and degummed oils showed high primary oxidation stability, while the bleached oil had a low incidence of secondary oxidation.

Systematic qualitative and quantitative assessment of fatty acids in the seeds of 60 tree peony (Paeonia section Moutan DC.) cultivars by GC-MS

Seeds from Paeonia ostii and Paeoniarockii have been recently identified as novel resources of α-linolenic acid (ALA) in China. To assess whether tree peony cultivars can be used as oil resource, fatty acids (FAs) in 60 cultivars were monitored and evaluated in this study. The results indicated that the composition and content of FAs varied dramatically among different cultivars, in which ALA, linoleic acid, oleic acid, palmitic acid, and stearic acid were the dominant. The 60 cultivars were classified into six clusters by hierarchical cluster analysis, and they were quite distinct from each other. Finally, six cultivars with high yield and high quality were screened out, comprising of 'Liuliguanzhu', 'Hongguanyupei', 'LSS-2', 'LSS-1', 'Jingshenhuanfa' and 'LSS-11'. These cultivars were appropriately applied in practical oil production. Overall, tree peony oil with abundant unsaturated fatty acids especially ALA was proved to be a top-grade source for edible oil and nutritional supplements.

Natural product agonists of peroxisome proliferator-activated receptor gamma (PPARγ): a review

Agonists of the nuclear receptor PPARγ are therapeutically used to combat hyperglycaemia associated with the metabolic syndrome and type 2 diabetes. In spite of being effective in normalization of blood glucose levels, the currently used PPARγ agonists from the thiazolidinedione type have serious side effects, making the discovery of novel ligands highly relevant.

Natural products have proven historically to be a promising pool of structures for drug discovery, and a significant research effort has recently been undertaken to explore the PPARγ-activating potential of a wide range of natural products originating from traditionally used medicinal plants or dietary sources. The majority of identified compounds are selective PPARγ modulators (SPPARMs), transactivating the expression of PPARγ-dependent reporter genes as partial agonists. Those natural PPARγ ligands have different binding modes to the receptor in comparison to the full thiazolidinedione agonists, and on some occasions activate in addition PPARα (e.g. genistein, biochanin A, sargaquinoic acid, sargahydroquinoic acid, resveratrol, amorphastilbol) or the PPARγ-dimer partner retinoid X receptor (RXR; e.g. the neolignans magnolol and honokiol). A number of in vivo studies suggest that some of the natural product activators of PPARγ (e.g. honokiol, amorfrutin 1, amorfrutin B, amorphastilbol) improve metabolic parameters in diabetic animal models, partly with reduced side effects in comparison to full thiazolidinedione agonists. The bioactivity pattern as well as the dietary use of several of the identified active compounds and plant extracts warrants future research regarding their therapeutic potential and the possibility to modulate PPARγ activation by dietary interventions or food supplements.