Targeted/untargeted metabolomics and antioxidant properties distinguish Citrus reticulata 'Chachi' from Citrus reticulata Blanco.

Dried citrus peel (DCP), also called "Chen Pi", has edible and medicinal value. However, the specific differences among various sources remain unknown. Herein, we collected six DCP species, namely, one Citrus reticulata 'Chachi' (CZG) and five Citrus reticulata Blanco (CRB). Targeted high-performance liquid chromatography and untargeted ultra-high-performance liquid chromatography-tandem mass spectrometry were employed to comprehensively compare the phenolic compounds and metabolites in DCP. Interestingly, 13 different phenolic compounds were noted in DCP. The total phenolic compound content in all CRB samples (58.86-127.65 mg/g) was higher than that of CZG (39.47 mg/g). Untargeted metabolomic revealed 1495 compounds, with 115 differentially expressed metabolites for CRBs and CZG, particularly flavonoids (38), terpenoids (15), and phenolic acids and derivatives (9). Lastly, antioxidant assays revealed that all CRB samples exhibited higher antioxidant activities compared with CZG. Therefore, our study results provide a theoretical basis for the high-value utilization of citrus peels and their metabolites.

Gastrointestinal digestion of yerba mate, rosemary and green tea extracts and their subsequent colonic fermentation by human, pig or rat inocula.

Polyphenolic compounds are common constituents of human and animal diets and undergo extensive metabolism by the gut microbiota before entering circulation. In order to compare the transformations of polyphenols from yerba mate, rosemary, and green tea extracts in the gastrointestinal tract, simulated gastrointestinal digestion coupled with colonic fermentation were used. For enhancing the comparative character of the investigation, colonic fermentation was performed with human, pig and rat intestinal microbiota. Chemical analysis was performed using a HPLC system coupled to a diode-array detector and mass spectrometer. Gastrointestinal digestion diminished the total amount of phenolics in the rosemary and green tea extracts by 27.5 and 59.2 %, respectively. These reductions occurred mainly at the expense of the major constituents of these extracts, namely rosmarinic acid (-45.7 %) and epigalocatechin gallate (-60.6 %). The yerba mate extract was practically not affected in terms of total phenolics, but several conversions and isomerizations occurred (e.g., 30 % of trans-3-O-caffeoylquinic acid was converted into the cis form). The polyphenolics of the yerba mate extract were also the least decomposed by the microbiota of all three species, especially in the case of the human one (-10.8 %). In contrast, the human microbiota transformed the polyphenolics of the rosemary and green extracts by 95.9 and 88.2 %, respectively. The yerba mate-extract had its contents in cis 3-O-caffeoylquinic acid diminished by 78 % by the human microbiota relative to the gastrointestinal digestion, but the content of 5-O-caffeoylquinic acid (also a chlorogenic acid), was increased by 22.2 %. The latter phenomenon did not occur with the rat and pig microbiota. The pronounced interspecies differences indicate the need for considerable caution when translating the results of experiments on the effects of polyphenolics performed in rats, or even pigs, to humans.

Biotransformation and Epithelial Toxicity of Prenylated Phenolics from Licorice Roots (Glycyrrhiza spp.) in 3D Apical-Out Mucus-Producing Human Enteroids.

Apical-out enteroids mimic the in vivo environment well due to their accessible apical surface and mucus layer, making them an ideal model for studying the impact of (bioactive) food compounds. Generated human ileal apical-out enteroids showed a fucose-containing mucus layer surrounding the apical brush border on their exposure side, indicating their physiological relevance. Effects on the mucosal epithelium of antibacterial prenylated phenolics (glabridin, licochalcone A, and glycycoumarin) from licorice roots were investigated for cytotoxicity, cell viability, barrier integrity, and biotransformation. At concentrations up to 500 µg mL-1, licochalcone A and glycycoumarin did not significantly affect apical-out enteroids, with cytotoxicities of -6 ± 2 and -2 ± 2% and cell viabilities of 77 ± 22 and 77 ± 13%, respectively (p > 0.05). Conversely, 500 µg mL-1 glabridin induced significant cytotoxicity (31 ± 25%, p < 0.05) and reduced cell viability (21 ± 14%, p < 0.01). Apical-out enteroids revealed differential sensitivities to prenylated phenolics not observed in apical-in enteroids and Caco-2 cells. Both enteroid models showed phase II biotransformation but differed in the extent of glucuronide conversion. The apical mucus layer of apical-out enteroids likely contributed to these differential interactions, potentially due to differences in electrostatic repulsion. This study underscores the relevance of 3D apical-out enteroid models and highlights the promise of prenylated phenolics for antimicrobial applications.

Comparative Evaluation of Micellization and Cellular Uptake of ß-Carotene Affected by Flavonoids.

Based on in vitro digestion, micellar synthesis, and Caco-2 cell model, this study investigated the effects of typical flavonoids in citrus (naringenin, naringin, hesperetin, hesperidin, quercetin, and rutin) at different doses on the micellization and cellular uptake of ß-carotene. In in vitro digestion, low-dose flavonoids enhanced ß-carotene bioaccesssibility by regulating the stability and dispersibility of the intestinal medium, particularly quercetin, which significantly increased the bioaccessibility by 44.6% (p < 0.05). Furthermore, naringenin, hesperetin, hesperidin, and quercetin enhanced the micellar incorporation rate of ß-carotene; however, naringin and rutin exhibited an opposite effect, particularly naringin, which significantly reduced it by 71.3% (p < 0.05). This phenomenon could be attributed to the high solubility of naringin and rutin in micelles, resulting in a competitive inhibitory effect on ß-carotene. Besides, all treatments significantly enhanced ß-carotene cellular uptake (p < 0.05) by promoting the expression of scavenger receptor class B type I and Niemann-Pick C1-Like 1.

Biochemical foundation of the aroma and antioxidant activity of Indian traditional rice landrace Maharaji and the effect of radiation-induced mutagenesis on its metabolome.

Maharaji rice, an aromatic variety with medium slender grains, is traditionally cultivated in the central regions of India. This study aimed to identify the biochemical compounds responsible for Maharaji rice's distinctive fragrance and enhance its agro-morphological traits through mutation breeding. Using Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) analysis, forty major metabolites were identified which may be responsible for its characteristic aroma. The bioactive compounds included terpenes, flavonoids, and amino acids. Maharaji brown rice extract exhibited potent radical scavenging activity. Radiation-induced mutation breeding improved the agro-morphological traits and also triggered biochemical diversification in different mutants. Maharaji Mutant-2 exhibited improved aroma due to higher abundance of aromatic compounds, improved yield and morphological characters as compared to the parent. This study, for the first time identifies the compounds associated with the characteristic aroma of Maharaji rice. Global metabolomics may, therefore, expedite the selection of mutants with suitable aroma and desirable biological properties.

Non-targeted metabolomics and explainable artificial intelligence: Effects of processing and color on coniferyl aldehyde levels in Eucommiae cortex.

Eucommia ulmoides, a plant native to China, is valued for its medicinal properties and has applications in food, health products, and traditional Chinese medicine. Processed Eucommiae Cortex (EC) has historically been a highly valued medicine. Ancient doctors had ample experience processing EC, especially with ginger juice, as documented in traditional Chinese medical texts. The combination of EC and ginger juice helps release and transform the active ingredients, strengthening the medicine's effectiveness and improving its taste and shelf life. However, the lack of quality control standards for Ginger-Eucommiae Cortex (G-EC), processed from EC and ginger, presents challenges for its industrial and clinical use. This study optimized G-EC processing using the CRITIC and Box-Behnken methods. Metabolomics showed 517 chemical changes between raw and processed G-EC, particularly an increase in coniferyl aldehyde (CFA). Explainable artificial intelligence techniques revealed the feasibility of using color to CFA content, providing insights into quality indicators.

Evaluation of the effect of roasting and digestion on biological activity of compounds of coffee extracts - in vitro assessment of the bioavailability, cytoprotective properties and modulation of inflammatory response.

Coffee is the most consumed beverage in the world. Consumption of phenolic compounds present in coffee protects the body against oxidative stress generation, inflammatory response, and cancer development. The aim of the study was evaluation of biological activity of coffee extracts (obtained from green, as well as light and dark roasted Robusta and Arabica beans) and isolated fractions on human colon adenocarcinoma Caco-2 cells, which are used as a cellular model of intestinal barrier in bioavailability studies. Additionally, impact of coffee phenolics on oxidative stress level and anti-inflammatory activity has been studied with RAW 264.7 macrophages used in immunomodulatory research. It was demonstrated that the coffee constituents protection against oxidative stress, lipotoxicity and secretion of proinflammatory mediators is correlated with the presence of mono- and dichlorogenic acids and roasting process. It was demonstrated that coffee phytochemicals can decrease cells proliferation and bind to topoisomerase IIα being a dietary tool in cancer prevention.

Differential characteristics of chemical composition, fermentation metabolites and antioxidant effects of polysaccharides from Eurotium Cristatum and Fu-brick tea.

Fu-brick tea (FBT) is predominately fermented by Eurotium Cristatum, FBT polysaccharides (FTPs) and Eurotium Cristatum extracellular polysaccharides (ECPs) are the main active substances in FBT and Eurotium Cristatum, respectively. FTPs was shown to exhibit higher levels of uronic acids, proteins, and polyphenols as compared to ECPs (p < 0.05), contributing to the superior antioxidant activity observed in FTPs. Additionally, FTPs had better water solubility and thermal stability than ECPs. Interestingly, in vitro digestive simulation revealed that FTPs and ECPs resist digestion in the stomach and small intestine. Excitingly, utilizing in vitro fermentation with feces from healthy individuals and type 2 diabetes mellitus (T2DM) patients demonstrated that FTPs and ECPs promote the production of SCFAs. Still, FTPs resulted in greater SCFAs contents than ECPs (p < 0.05). Moreover, FTPs and ECPs fermentation by T2DM patients' fecal microbiota affected different metabolomic pathways. Our findings suggested that FTPs holds great promise for application in functional foods.

The potential of dried Ginkgo Biloba leaves as a novel ingredient in fermented beverages of enhanced flavour and antioxidant properties.

Fermentation enhances the nutritional profile of foods and beverages like beer, wine, and fermented teas. Ginkgo biloba, long utilized for its health-enhancing properties, contains bioactive compounds like terpene trilactones and flavonoids, known for their antioxidant and neuroprotective effects. This study explores the feasibility of using dried Ginkgo biloba leaves in SCOBY-mediated fermentation to produce novel health-promoting beverages similar to kombucha. Infusions of dried Ginkgo biloba leaves with varying sugar concentrations are fermented over 21 days. Results showed that these beverages exhibited potent antioxidant properties, notably higher than tea-kombucha, attributed to increased polyphenol content. HPLC analysis identified significant levels of bioactive compounds such as catechin and apigenin. Sensory evaluation highlighted optimal acceptance of the seven-day fermented product. This research underscores the potential of Ginkgo biloba as a functional ingredient in fermented beverages, offering a healthier alternative to conventional soft drinks.

Lactobacillus fermentation accelerated biotransformation of cranberry anthocyanins towards phenol-pyranoanthocyanins and their stability and antioxidant property.

Phenol-pyranoanthocyanins, a structurally modified type of anthocyanin, has higher stability than anthocyanins. However, their conversion occurs slowly. Therefore, it is crucial to improve the conversion efficiency and production of pyranoanthocyanins. In this study, cranberry anthocyanin (CRAN) was fermented using two Lactobacillus strains along with caffeic acid to form cranberry-derived pyranoanthocyanins (PY-CRAN). PY-CRAN was characterized and identified. The physicochemical properties, antioxidant activity, and tyrosinase inhibitory capacity of PY-CRAN were assessed. The results showed that phenol-pyranoanthocyanins can be rapidly produced through fermentative transformation using Lactiplantibacillus plantarum and Lacticaseibacillus paracasei. Lacticaseibacillus paracasei exhibits a higher propensity for producing phenol-pyranoanthocyanins. PY-CRAN exhibits high stability under light and various pH conditions. Moreover, they possess excellent antioxidant properties and the ability to inhibit tyrosinase. These results suggest that fermentative biotransformation conducted by Lactobacillus is an ideal method for producing cranberry pyranoanthocyanins. The resulting anthocyanins have potential as antioxidant and whitening agents, making them promising bioactive ingredients.

HRMAS 1H NMR and CPMAS 13C NMR spectroscopies coupled with chemometrics for the metabolomic investigation of commercial teas.

In this study, the metabolome of different types of tea (i.e., black, green and earl grey) is explored by means of HRMAS 1H (i.e., semisolid state) NMR and CPMAS 13C (i.e., solid state) NMR spectroscopies. By elaborating the metabolomic data with unsupervised and supervised chemometric tools (PCA, PLS-DA), it was possible to set up classification models with the aim to discriminate the different types of tea as based on differences in their chemical composition. Both the applications of the NMR spectroscopies also allowed to obtain information about the metabolic biomarkers leading the differentiation among teas. These were mainly represented by phenolic compounds. Also, some non-phenolic compounds, such as amino acids, carbohydrates, and terpenoids, played important roles in shaping tea quality. The findings of this study provided useful insights into the application of solid and semisolid state NMR spectroscopies, in combination with chemometrics, in the context of food authentication and traceability.

An untargeted metabolomics approach applied to the study of the bioavailability and metabolism of three different bioactive plant extracts in human blood samples.

Advances in the understanding of bioavailability and metabolism of bioactive compounds have been achieved primarily through targeted or semi-targeted metabolomics approaches using the hypothesis of potential metabolized compounds. The recent development of untargeted metabolomics approaches can present great advantages in this field, such as in the discovery of new metabolized compounds or to study the metabolism of compounds from multiple matrices simultaneously. Thus, this study proposes the use of an untargeted metabolomics strategy based on HPLC-ESI-QTOF-MS for the study of bioavailability and metabolism of bioactive compounds from different vegetal sources. Specifically, this study has been applied to plasma samples collected in an acute human intervention study using three matrices (Hibiscus sabdariffa, Silybum marianum and Theobroma cacao). This approach allowed the selection of those significant variables associated with exogenous metabolites derived from the consumption of bioactive compounds for their subsequent identification. As a result, 14, 25 and 3 potential metabolites associated with supplement intake were significantly detected in the plasma samples from volunteers who ingested the H. sabdariffa (HS), S. marianum (SM) and T. cacao (TC) extracts. Furthermore, Tmax values have been computed for each detected compound. The results highlight the potential of untargeted metabolomics for rapid and comprehensive analysis when working with a wide range of exogenous metabolites from different plant sources in biological samples.

New findings in the metabolism of the saffron apocarotenoids, crocins and crocetin, by the human gut microbiota.

The main constituents of saffron are the apocarotenoids crocins and crocetin, present in the stigmas. Numerous healthy properties, especially those related to the effects on the central nervous system, have been attributed to these compounds but the metabolites responsible for these effects are still unknown. Previous evidences in animal models suggest a role for the gut microbiota in the pharmacokinetics and the neuroprotective effects of these compounds. However, the interaction between these apocarotenoids and the gut microbiota has been poorly studied. In this article, we have thoroughly investigated the batch fermentation of crocin-1 and crocetin (10 µM) with human fecal samples of two donors at different incubation times (0-240 h) using a metabolomic approach. We corroborated a rapid transformation of crocin-1 which looses the glucose molecules through de-glycosylation reactions until its complete transformation into crocetin in 6 hours. A group of intermediate crocins with different degrees of glycosylation were detected in a very short time. Crocetin was further metabolized and new microbial metabolites produced by double-bond reduction and demethylation reactions were identified for the first time: dihydro and tetrahydro crocetins and di-demethyl crocetin. In addition, we detected changes in the levels of the short chain fatty acids valeric acid and hexanoic acid suggesting further structural modifications of crocetin or changes in the catabolic production of these compounds. This research is a pioneering study of the action of the human gut microbiota on the saffron apocarotenoids and goes one step further towards the discovery of metabolites potentially involved in the benefits of saffron.

Prioritization before dereplication, an effective strategy to target new metabolites in whole extracts: ghosalin from Murraya paniculata root.

Re-discovery of known metabolites is a common challenge in natural product-based drug discovery, and to avoid re-discovery, dereplication has been proposed for identifying known metabolites at the early stage of isolation. A majority of methods use LCMS to profile the extract and ignore the known mass. LC-HRMS profiling may generate a long mass list of metabolites. The identification of a new metabolite is difficult within the mass list. To overcome this, it was hypothesized that identifying a 'new metabolite' in the whole metabolome is more difficult than identifying it within the class of metabolites. A prioritization strategy was proposed to focus on the elimination of unknown and uncommon metabolites first using the designed bias filters and to prioritize the known secondary metabolites. The study employed Murraya paniculata root for the identification of new metabolites. The LC-HRMS-generated mass list of 509 metabolites was subjected to various filters, which resulted in 93 metabolites. Subsequently, it was subjected to regular dereplication, resulting in 10 coumarins, among which 3 were identified as new. Further, chromatographic efforts led to the isolation of a new coumarin, named ghosalin (1). The structure of the new compound was established through 2D NMR and X-ray crystallography. Cytotoxicity studies revealed that ghosalin has significant cytotoxicity against cancer cell lines. The proposed prioritization strategy demonstrates an alternative way for the rapid annotation of a particular set of metabolites to isolate a new metabolite from the whole metabolome of a plant extract.

Characterization and identification of the key volatile and non-volatile substances of Vangueria madagascariensis J.F. Gmel fruits (Kirkir) and exploration of their binding interactions with olfactory and taste receptors using computational chemistry methodology.

Profiling of metabolites that contribute to the taste and odor of fruit products is important to produce the desired products. In this study, volatile and non-volatile compounds were analyzed using SPME/GC-MS and UHPLC-Q-Exactive-orbitrap-MS/MS, respectively. A total of 59 volatiles (including alcohols, aldehydes, acids, terpenes, ketones, phenols, and hydrocarbons et al.) and 18 non-volatiles (including phenolic acids, flavones, flavonoids, glucosides, phenols, and quinic acid derivatives et al.) were detected in dried Kirkir fruits. The binding interactions between the key volatiles and the detected non-volatiles with taste and olfactory receptors were also evaluated. Based on the molecular docking, 11 volatile compounds may contribute to the overall odor, while 16 non-volatile compounds may contribute to the taste of the Kirkir fruits. In conclusion, in silico studies can serve as a powerful technique for understanding mechanisms of interaction and predicting the key phytochemicals that contribute to the odor and taste of fruits.

Volatile and non-volatile metabolite profiling of under-explored crop Piper colubrinum Link. with chromatography mass spectrometry approach and its biochemical diversity from medicinally valued Piper species.

Piper colubrinum Link. is an underexplored crop regarding its metabolites and therapeutic attributes. Current study aimed to identify the possible volatile and non-volatile metabolites of P. colubrinum fruit and studied its metabolite diversity with medicinally valued Piper species viz. P. nigrum L., P. longum L. and P. chaba Hunter. The volatile constituents of P. colubrinum essential oil by GC-MS revealed the presence of sesquiterpenes as the major contribution. The sesquiterpenes α-muurolol (12.5 %) and ß-caryophyllene (11.3 %) were the predominant volatile components. Few aliphatic compounds like n-heptadecane and trace amounts of monoterpenes (α- and ß-pinene and α-terpineol) were also identified from this crop. The fatty acid profiling by GC-MS revealed mainly oleic acid (41.3 %) followed by palmitic and linoleic acids. HPLC analysis demonstrated that the major pungent alkaloid piperine was found to be trace (0.04 %) in P. colubrinum. The LC-QTOF-MS/MS profiling of the chloroform extract of the P. colubrinum revealed the presence of non-volatile constituents including phenolic and alkaloid compounds. Ferulic acid, rosmarinic acid, salicylic acid, kaempferol-5-glucoside, 5-methoxysalicylic acid, apigenin-7-galactoside, kaempferide-3-glucoside, luteolin, kaempferol, apigenin and scutellarein-4'-methyl ether were the phenolic compounds whereas piperlonguminine was the alkaloid compound identified. Finally, the biochemical parameters of this crop were compared with that of P. nigrum, P. longum and P. chaba and average linkage cluster dendrogram revealed that P. colubrinum was biochemically distinct from other three Piper species.

Bioaccessibility of iron in developed pectin iron complex using Citrus limon Burm F. peels subjected to in-vitro gastro-pancreatic digestion.

Pectin from the citrus peel waste has novel applications in food and biomedical industries. The present work focused on addressing iron deficiency, which is a global health concern, by developing a functional ingredient using pectin extracted from Assam lemon (Citrus limon Burm. F) and supplementing iron via the pectin­iron complex (PIC). Extracted pectin was incubated with iron chloride hexahydrate (0.90-1.80 mM) for 180 h to optimize the complexation conditions, with the optimal concentration being 1.36 mM. The iron bioavailability and its absorption in the PIC was assessed using in-vitro simulation digestion and Caco-2 cell monolayers. The bioaccessible form of iron in the developed PIC during the intestinal phase was 5.34 ± 0.16%, which was negligible in pectin. The absorption of bioaccessible iron in the PIC was found to be 2.93 ± 0.03%. The results demonstrated that PIC could reduce iron deficiency and increase fibre intake, leading to several health benefits.

Bioaccessibility of bioactive compounds from Pereskia aculeata and their cellular antioxidant effect.

Ora-pro-nobis (Pereskia aculeata) is a Cactaceae plant with edible leaves and fruits whose extracts are consumed to promote health, albeit bioactive compounds' bioaccessibility was still not assessed. To address this, ora-pro-nobis fruits (FE) and leaf extracts (LE) were subjected to in vitro digestion to better understand how this process impacts the bioactivities of the extracts. The study investigated the composition of the extracts, their cytotoxicity, and their chemical, plasmatic, and cellular antioxidant capacity. The results revealed that total polyphenolics were about 70% bioaccessible in LE and FE, with phenylalanine being the most bioaccessible essential amino acid in leaves (42.7%) and fruits (83.6%). The samples' antioxidant activity (CUPRAC) was reduced by 25%. LE demonstrated antioxidant activity against human plasma oxidation and haemolysis (21.8%), but digestion mitigated these activities. FE diminished haemolysis (47.0%) and presented cytotoxicity (IC50 = 1086 µg/mL) to HUVEC cells, but these properties were lost following digestion. Ultimately, digestion partially degraded the samples' bioactive compounds, diminishing their cellular protection against oxidative stress.

Structural characterization of oligosaccharide from Dendrobium officinale and its properties in vitro digestion and fecal fermentation.

Oligosaccharides from Dendrobium officinale (DOO) is a kind of new potential prebiotic for health. In this study, structural characteristics, digestion properties and regulatory function on intestinal flora of DOO were investigated. An oligosaccharide, DOO 1-1, was purified by DEAE-Sepharose Fast Flow and Sephadex G-25, and its physicochemical properties were characterized as a glucomannan oligosaccharide with a molecular weight of 1560 Da (DP = 9). In vitro simulated digestion, it proved that the structure of DOO 1-1 was degraded hardly in the simulated gastric and small intestinal fluid. By evaluating the gas, short-chain fatty acids and intestinal microbiota in vitro fermentation, DOO has an excellent regulatory effect on intestinal microbiota, especially promoting the proliferation of Bacteroidetes and Actinobacteria. Therefore, DOO can be used as a potential prebiotic in functional foods.

Effects of different cold plasma treatments on chemical composition, phenolics bioaccessibility and microbiota of edible red mini-roses.

This study evaluated the effect of dielectric barrier discharge (DBD) and glow discharge (glow) cold plasma treatments in color, sugars, organic acids, phenolics (concentration and bioaccessibility), antioxidant activity, volatiles, and microbiota of edible mini-roses. Plasma treatments did not affect the flowers' color, while they increased organic acids and phenolics. Flowers treated with DBD had a higher concentration of most phenolics, including hesperidin (84.04 µg/g) related to antioxidant activity, and a higher mass fraction of most volatiles, including octanal (16.46% after 5 days of storage). Flowers treated with glow had a higher concentration of pelargonidin 3,5-diglucoside (392.73 µg/g), greater bioaccessibility of some phenolics and higher antioxidant activity. Plasma treatments reduced the microbiota diversity in mini-roses. Regardless of the plasma treatment, phylum Proteobacteria, family Erwiniaceae, and genus Rosenbergiella were the dominant groups. Results indicate plasma treatments as promising technologies to improve the quality and increase phenolic and specific volatile compounds in mini-roses.