Food Polyphenols Research Articles

Pea eggplant (Solanum torvum Swartz) is a source of plant food polyphenols with SARS-CoV inhibiting potential.

Pea eggplant (Solanum torvum Swartz) commonly known as turkey berry or 'terung pipit' in Malay is a vegetable plant widely consumed by the local community in Malaysia. The shrub bears pea-like turkey berry fruits (TBFs), rich in phytochemicals of medicinal interest. The TBF phytochemicals hold a wide spectrum of pharmacological properties. In this study, the TBF phytochemicals' potential inhibitory properties were evaluated against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) of the Coronavirus disease 2019 (COVID-19). The TBF polyphenols were screened against SARS-CoV receptors via molecular docking and the best receptor-ligand complex was validated further by molecular dynamics (MD) simulation. The SARS-CoV receptor structure files (viral structural components) were retrieved from the Protein Data Bank (PDB) database: membrane protein (PDB ID: 3I6G), main protease (PDB ID: 5RE4), and spike glycoproteins (PDB ID: 6VXX and 6VYB). The receptor binding pocket regions were identified by Discovery Studio (BIOVIA) for targeted docking with TBF polyphenols (genistin, kaempferol, mellein, rhoifolin and scutellarein). The ligand and SARS-CoV family receptor structure files were pre-processed using the AutoDock tools. Molecular docking was performed with the Lamarckian genetic algorithm using AutoDock Vina 4.2 software. The best pose (ligand-receptor complex) from the molecular docking analysis was selected based on the minimum binding energy (MBE) and extent of structural interactions, as indicated by BIOVIA visualization tool. The selected complex was validated by a 100 ns MD simulation run using the GROMACS software. The dynamic behaviour and stability of the receptor-ligand complex were evaluated by the root mean square displacement (RMSD), root mean square fluctuation (RMSF), radius of gyration (Rg), solvent accessible surface area (SASA), solvent accessible surface volume (SASV) and number of hydrogen bonds. At RMSD = 0, the TBF polyphenols showed fairly strong physical interactions with SARS-CoV receptors under all possible combinations. The MBE of TBF polyphenol-bound SARS CoV complexes ranged from -4.6 to -8.3 kcal/mol. Analysis of the structural interactions showed the presence of hydrogen bonds, electrostatic and hydrophobic interactions between the receptor residues (RR) and ligands atoms. Based on the MBE values, the 3I6G-rhoifolin (MBE = -8.3 kcal/mol) and 5RE4-genistin (MBE = -7.6 kcal/mol) complexes were ranked with the least value. However, the latter showed a greater extent of interactions between the RRs and the ligand atoms and thus was further validated by MD simulation. The MD simulation parameters of the 5RE4-genistin complex over a 100 ns run indicated good structural stability with minimal flexibility within genistin binding pocket region. The findings suggest that S. torvum polyphenols hold good therapeutics potential in COVID-19 management.

Hitchhiking into a cell: flavonoids may produce complexes with transition metals for transmembrane translocation.

Flavonoids are a group of food polyphenols that are delivered to the human body with plant foods. In recent years, these substances have attracted the attention of researchers due to their effectiveness in preventing a wide variety of diseases, including neurodegenerative, oncological, autoimmune, and cardiovascular. Similar pathologies may also occur with a lack of some first-row transition metals, including Cu(II), Zn(II), Mn(II), Fe(II/III). It is noteworthy that flavonoids are known as transition metal chelators. When a complex with these metals is formed, the therapeutic effect of flavonoids can be enhanced, assuming the possibility of synergy. Molecular models have shown that the lipophilicity of flavonoid-metal complexes can vary significantly depending on their binding stoichiometry. Therefore, a unique process of translocation of flavonoid-metal complexes of various lipophilicity through cell membranes is assumed, based on the possibility of their sequential association and dissociation, called "hitchhiking". It is expected that studies of the interaction of flavonoids with metals will improve the effectiveness of drugs based on flavonoids.

Structure and biomedical applications of bioactive polyphenols from food and fruits

AbstractPolyphenols, a class of bioactive compounds existing in food and fruit, play an essential role in anti‐oxidation, anti‐inflammation, anticancer, anti‐atherosclerosis, and antiaging by scavenging free radicals, regulating cellular redox potential, signaling pathways, and so on. Due to the low bioavailability/high activity paradox, the functional mechanism of polyphenols in biomedicine has attracted widespread attention. This review summarizes polyphenols (especially quercetin) chemical structure and bioactive mechanism (signaling pathways, enzyme activity, cell redox potential, and gene expression) to show in‐depth biomedical functional mechanisms for the control of chronic heath diseases such as oxidation, inflammation, cancer, atherosclerosis, and aging. This study can deepen the understanding of polyphenols' effects on human health.Novelty impact statement Providing another perspective for the comprehensive reuse of polyphenols in food and fruit. Summarizing the polyphenols in biomedical research progress of function mechanism. Deeping the understanding of the effects of polyphenols on human health.

In Vitro and In Vivo Digestive Fate and Antioxidant Activities of Polyphenols from Hulless Barley: Impact of Various Thermal Processing Methods and β-Glucan.

The unfavorable bioaccessibility of polyphenols in cereal-based food limits their physiological functions as most polyphenols bind spontaneously to the cell-wall polysaccharides. Effects of β-glucan and various thermal processing methods including flaking and roasting, stir-frying, steam-flash explosion, and popping expansion on the bioaccessibility and antioxidant properties of polyphenols from hulless barley in vitro and in vivo were investigated in this study. The bioaccessibility and antioxidant capacity (via DPPH, ·OH, and ·O2- free radical scavenging, TAC, and FRAP assays) of polyphenol extracts from hulless barley treated by steam-flash explosion and popping expansion increased significantly before and after in vitro digestion compared to those from raw and other processed hulless barley. Further, the total polyphenol content of hulless barley elevated dramatically following hydrolyzing with β-glucanase, which was positively correlated with the antioxidant activity. Additionally, the hulless barley treated with steam-flash explosion exhibited potent antidiabetic effects and antioxidant capacity (via TAC, SOD, GSH-Px, CAT, and MDA assays) in type 2 diabetic rats. The absorption of individual phenolic compounds in the alimentary canal of rats was impacted obviously by thermal processing. This study provides new insights into enhancing the bioaccessibility of the polyphenols and suggests that β-glucans interact with polyphenols and proteins in the hulless barley matrix.

Health benefits of polyphenols: A concise review.

Plants produce polyphenols, which are considered highly essential functional foods in our diet. They are classified into several groups according to their diverse chemical structures. Flavanoids, lignans, stilbenes, and phenolic acids are the four main families of polyphenols. Several in vivo and in vitro research have been conducted so far to evaluate their health consequences. Polyphenols serve a vital function in the protection of the organism from external stimuli and in eliminating reactive oxygen species (ROS), which are instigators of several illnesses. Polyphenols are present in tea, chocolate, fruits, and vegetables with the potential to positively influence human health. For instance, cocoa flavan-3-ols have been associated with a decreased risk of myocardial infarction, stroke, and diabetes. Polyphenols in the diet also help to improve lipid profiles, blood pressure, insulin resistance, and systemic inflammation. Quercetin, a flavonoid, and resveratrol, a stilbene, have been linked to improved cardiovascular health. Dietary polyphenols potential to elicit therapeutic effects might be attributed, at least in part, to a bidirectional association with the gut microbiome. This is because polyphenols are known to affect the gut microbiome composition in ways that lead to better human health. Specifically, the gut microbiome converts polyphenols into bioactive compounds that have therapeutic effects. In this review, the antioxidant, cytotoxicity, anti-inflammatory, antihypertensive, and anti-diabetic actions of polyphenols are described based on findings from in vivo and in vitro experimental trials. PRACTICAL APPLICATIONS: The non-communicable diseases (NCDs) burden has been increasing worldwide due to the sedentary lifestyle and several other factors such as smoking, junk food, etc. Scientific literature evidence supports the use of plant-based food polyphenols as therapeutic agents that could help to alleviate NCD's burden. Thus, consuming polyphenolic compounds from natural sources could be an effective solution to mitigate NCDs concerns. It is also discussed how natural antioxidants from medicinal plants might help prevent or repair damage caused by free radicals, such as oxidative stress.

Recent advances on the stability of dietary polyphenols

Recent advances on the stability of dietary polyphenols

The Effects of Berry Polyphenols on the Gut Microbiota and Blood Pressure: A Systematic Review of Randomized Clinical Trials in Humans.

Berry consumption has beneficial effects on blood pressure. Intestinal microbiota transform berry phytochemicals into more bioactive forms. Thus, we performed a systematic review of randomized clinical trials to determine whether berry polyphenols in foods, extracts or supplements have effects on both the profile of gut microbiota and systolic and diastolic blood pressure in humans. PubMed, Cochrane Library, Scopus, and CAB s (EBSCOhost) were searched for randomized clinical trials in humans published from 1 January 2011 to 29 October 2021. Search results were imported into Covidence for screening and data extraction by two blinded reviewers, who also performed bias assessment independently. The literature search identified 216 publications; after duplicates were removed, 168 publications were screened with 12 full-text publications assessed for eligibility. Ultimately three randomized clinical trials in humans met the eligibility criteria. One randomized clinical trial showed a low risk of bias while the other two randomized clinical trials included low, high or unclear risk of bias. Together the randomized clinical trials showed that berry consumption (Aronia berry, strawberries, raspberries, cloudberries and bilberries) for 8–12 weeks had no significant effect on both blood pressure and the gut microbiota. More randomized clinical trials are needed to determine the effects of berry consumption on the profile of gut microbiota and blood pressure in humans.

Insights into interactions between food polyphenols and proteins: An updated overview

Polyphenols are widely distributed natural products, investigated intensively due to their health-beneficial effects and prevention of several human diseases. It is well known that polyphenols can easily form complexes with proteins in food processing and human digestion, leading to changes in the conformation and functionality of polyphenols and proteins. On the basis of dividing the common polyphenols into flavonoids, phenolic acids, and tannins, this paper reviews the progress and application of polyphenol–protein interactions during the past decade. Accordingly, this review might provide a better understanding on the mechanism of polyphenol–protein interactions, which is expected to provide guidance for food processing and studying on health effects of polyphenol compounds in the future. Novelty impact statement The interactions of flavonoids, phenolic acids, and tannins with proteins were reviewed. Reversible interactions are the main form of polyphenol–protein interactions, which are mainly attributed to hydrogen and hydrophobic bonding. Besides, the health effects of polyphenol–protein complexes mainly include the inhibition of protease and toxic protein aggregation.

Natural Polyphenols for the Preservation of Meat and Dairy Products.

Food spoilage makes foods undesirable and unacceptable for human use. The preservation of food is essential for human survival, and different techniques were initially used to limit the growth of spoiling microbes, e.g., drying, heating, salting, or fermentation. Water activity, temperature, redox potential, preservatives, and competitive microorganisms are the most important approaches used in the preservation of food products. Preservative agents are generally classified into antimicrobial, antioxidant, and anti-browning agents. On the other hand, artificial preservatives (sorbate, sulfite, or nitrite) may cause serious health hazards such as hypersensitivity, asthma, neurological damage, hyperactivity, and cancer. Thus, consumers prefer natural food preservatives to synthetic ones, as they are considered safer. Polyphenols have potential uses as biopreservatives in the food industry, because their antimicrobial and antioxidant activities can increase the storage life of food products. The antioxidant capacity of polyphenols is mainly due to the inhibition of free radical formation. Moreover, the antimicrobial activity of plants and herbs is mainly attributed to the presence of phenolic compounds. Thus, incorporation of botanical extracts rich in polyphenols in perishable foods can be considered since no pure polyphenolic compounds are authorized as food preservatives. However, individual polyphenols can be screened in this regard. In conclusion, this review highlights the use of phenolic compounds or botanical extracts rich in polyphenols as preservative agents with special reference to meat and dairy products.

Current Advances in Multifunctional Nanocarriers Based on Marine Polysaccharides for Colon Delivery of Food Polyphenols.

Inflammatory bowel disease (IBD) has been considered as a chronic disease that is difficult to cure and needs lifelong treatment. Marine polysaccharides with good biocompatibility and biodegradability, mucoadhesion, sensitivity to external stimuli, and targeting ability can be used as wall materials for oral colon-targeted delivery of polyphenols in nutrition intervention of IBD. This manuscript reviewed the latest progress in the design, preparation, and characterization of marine polysaccharides-derived multifunctional nanocarriers for polyphenol colon delivery. Chitosan, sodium alginate, chondroitin sulfate, and hyaluronic acid were discussed in the preparation of polyphenol delivery systems. The design strategy, synthesis methods, and structure characterization of multifunctional polyphenol carriers including stimuli-responsive nanocarriers, mucoadhesive and mucus-penetrating nanocarriers, colon targeted nanocarriers, and bioactive compounds codelivery nanocarriers were reviewed in the alleviation of IBD. The research perspectives in the preparation and characterization of delivery carriers using marine polysaccharide as materials were proposed for their potential application in food bioactive components.

Evaluation and Comparison of the Antioxidant Activity of Extractable Polyphenols and Non-extractable Polyphenols of Sour Orange Peel

Background and Objectives Research on food polyphenols has experienced a huge development during the last century. Most studies on polyphenolic compounds have focused on extractable polyphenols (EPP). However, an important polyphenolic fraction is ignored (Non-Extractable polyphenols (NEPP)) because they are trapped in the corresponding extraction residues. In this study, the antioxidant EPP and NEPP of sour orange peel, extracted by aqueous solvent and acid hydrolysis (with two different solvent systems) respectively, are evaluated and compared. Methods Antioxidant activity was evaluated by four tests of radical inhibition of 2, 2-diphenyl-1-picrylhydrazyl (DPPH), 2, 2-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP) and iron chelating. The amount of polyphenolic compounds, flavonoids, oligomeric proanthocyanidins, and flavanones were respectively determined by folin-ciocalteu, Aluminium chloride (AlCl3) and Ultraviolet–visible spectroscopy (UV-visible). Also, the anti-lipid peroxidation effect in rat liver was measured. Results The results of antioxidant analysis showed that NEPP with methanol/Sulfuric Acid Solvent had the highest level of antioxidant activity in sour orange peel. It can be due to the high polyphenolic compounds in this extraction compared to the others. Conclusion All extracts had antioxidant activity and can be suggested as a potential natural source in food and pharmaceutical industries.

Effects and underlying mechanisms of food polyphenols in treating gouty arthritis: A review on nutritional intake and joint health.

Gouty arthritis, one of the most severe and common forms of arthritis, is characterized by monosodium urate crystal deposition in joints and surrounding tissues. Epidemiological evidence indicates that gouty arthritis incidence is sharply rising globally. Polyphenols are found in many foods and are secondary metabolites in plant foods. The anti-inflammatory and antioxidant effects of food polyphenols have been extensively studied in many inflammatory chronic diseases. Research has suggested that many food polyphenols have excellent anti-gouty arthritis effects. The mechanisms mainly include (a) inhibiting xanthine oxidase activity; (b) reducing the levels of inflammatory cytokines and chemokines; (c) inhibiting the activation of signaling pathways and the NLRP3 inflammasome; and (d) reducing oxidative stress. This paper reviews the research progress and pathogenesis of gouty arthritis and introduces the mechanisms of food polyphenols in treating gouty arthritis, which aims to explore the potential of functional foods in the treatment of gouty arthritis. PRACTICAL APPLICATIONS: The incidence rate of gouty arthritis has increased sharply worldwide, which has seriously affected people's quality of life. According to the current research progress, food polyphenols alleviate gouty arthritis through anti-inflammatory and antioxidant effects. This paper reviews the research progress and molecular pathogenesis of gouty arthritis and introduces the mechanisms of food-derived polyphenols in the treatment of gouty arthritis, which is helpful to the prevention and treatment of gouty arthritis.

TiO2 nanoparticles negatively impact the bioavailability and antioxidant activity of tea polyphenols

This study was to investigate the influence of TiO2 nanoparticles (NPs) on the stability, bioavailability, and antioxidant activity of co-ingested tea polyphenols extract using an in vitro digestion model. The tea polyphenol contents decreased significantly after addition of 0.5 % (w/w) TiO2 NPs. The gallocatechin gallate level decreased the most, changing from 101.9 to 27.2 µg/mL (about 73.3%). The TiO2 NPs also reduced the bioavailability of the tea polyphenols in a dose-dependent manner, which was ascribed to the formation of large polyphenol-TiO2 NP complex aggregates that could not pass through the pores in the dialysis tube used to simulate the gut wall. Additionally, the TiO2 NPs decreased the antioxidant activity of the tea polyphenols within the simulated gastrointestinal tract. In summary, our results show that high levels of TiO2 NPs (but within the current legal limits in many countries) may negatively impact the bioavailability and bioactivity of polyphenols in foods.

Structure-based identification of galectin-1 selective modulators in dietary food polyphenols: a pharmacoinformatics approach

In this study, a set of dietary polyphenols was comprehensively studied for the selective identification of the potential inhibitors/modulators for galectin-1. Galectin-1 is a potent prognostic indicator of tumor progression and a highly regarded therapeutic target for various pathological conditions. This indicator is composed of a highly conserved carbohydrate recognition domain (CRD) that accounts for the binding affinity of β-galactosides. Although some small molecules have been identified as galectin-1 inhibitors/modulators, there are limited studies on the identification of novel compounds against this attractive therapeutic target. The extensive computational techniques include potential drug binding site recognition on galectin-1, binding affinity predictions of ~ 500 polyphenols, molecular docking, and dynamic simulations of galectin-1 with selective dietary polyphenol modulators, followed by the estimation of binding free energy for the identification of dietary polyphenol-based galectin-1 modulators. Initially, a deep neural network-based algorithm was utilized for the prediction of the druggable binding site and binding affinity. Thereafter, the intermolecular interactions of the polyphenol compounds with galectin-1 were critically explored through the extra-precision docking technique. Further, the stability of the interaction was evaluated through the conventional atomistic 100 ns dynamic simulation study. The docking analyses indicated the high interaction affinity of different amino acids at the CRD region of galectin-1 with the proposed five polyphenols. Strong and consistent interaction stability was suggested from the simulation trajectories of the selected dietary polyphenol under the dynamic conditions. Also, the conserved residue (His44, Asn46, Arg48, Val59, Asn61, Trp68, Glu71, and Arg73) associations suggest high affinity and selectivity of polyphenols toward galectin-1 protein.Graphic

Fast Antioxidant Reaction of Polyphenols and Their Metabolites.

The negative correlation between diets rich in fruits and vegetables and the occurrence of cardiovascular disease, stroke, cancer, atherosclerosis, cognitive impairment and other deleterious conditions is well established, with flavonoids and other polyphenols held to be partly responsible for the beneficial effects. Initially, these effects were explained by their antioxidant ability, but the low concentrations of polyphenols in tissues and relatively slow reaction with free radicals suggested that, instead, they act by regulating cell signalling pathways. Here we summarise results demonstrating that the abandonment of an antioxidant role for food polyphenols is based on incomplete knowledge of the mechanism of the polyphenol-free radical reaction. New kinetic measurements show that the reaction is up to 1000 times faster than previously reported and lowers the damaging potential of the radicals. The results also show that the antioxidant action does not require phenolic groups, but only a carbon-centred free radical and an aromatic molecule. Thus, not only food polyphenols but also many of their metabolites are effective antioxidants, significantly increasing the antioxidant protection of cells and tissues. By restoring an important antioxidant role for food polyphenols, the new findings provide experimental support for the advocacy of diets rich in plant-derived food.

Polyphenols profile and antioxidant capacity of selected medicinal plants of Bangladesh

Polyphenols in many plant foods have received a great deal of attention due to their biological potency and postulated protective role against certain non-communicable diseases like cancer, neurodegenerative disease, and cardiovascular disease. The current study focuses on 15 indigenous plants which are traditionally being used for medicinal and other purposes in Bangladesh. Specifically, this study aimed to determine the total phenolic content (TPC), profile the polyphenolic composition, and assess the antioxidant capacity (AC) of water and methanol extracts derived from these plants. The TPC was estimated using the Folin-Ciocalteu method, and DPPH inhibition was used to assess the AC. HPLC-centered simultaneous determination method of polyphenols was employed to identify and quantify individual polyphenolic compounds. TPC content (expressed as mg GAE/100 g FW) ranged from 15.5 (Zanthoxylum rhetsa) to 276.9 (Moringa oleifera). The lowest IC50 in the water and methanol extracts were shown by Moringa oleifera and Zanthoxylum rhetsa respectively and they also exhibited high free radical scavenging activity in the corresponding solvents (91.9% and 92.9% DPPH inhibition by Moringa oleifera and Zanthoxylum rhetsa respectively). The lowest DPPH inhibition was observed in Alternanthera philoxeroides (29.8%) and Spilanthes calva (24.5%) in the water and methanol extracts respectively. Ten polyphenols (coumaric acid, chlorogenic acid, caffeic acid, apigenin, apigenin-7-O-neohesperidoside, quercetin-3-β-D-glucoside, luteolin, quercetin-3-O-β-D-glucopyranoside, isorhamnetin and kaempferol) were initially identified and subsequently quantified in the plant extracts. Spilanthes calva, Moringa oleifera, Oxalis corniculata, and Piper retrofractum contained the highest amount of coumaric acid and chlorogenic acid, apigenin, caffeic acid and apigenin-7-O-neohesperidoside respectively. Senna tora had the greatest amount of kaempferol, quercetin-3-β-D-glucoside, and isorhamnetin whereas luteolin and quercetin-3-O-β-D-glucopyranoside were observed to be the maximum in Alternanthera sessilis. To conclude, Moringa oleifera and Senna tora with high percentage of DPPH inhibition and low IC50 were the most potent antioxidant sources among the analyzed samples.
 Bioresearch Commu. 7(1): 947-954, 2021 (January)

Polyphenols in foods: Classification, methods of identification, and nutritional aspects in human health.

Polyphenols widely exists in various foods, including main crops, fruits, beverages and some wines. Famous representatives of polyphenols, such as resveratrol in red wine, (-)-epigallocatechin gallate in green tea, chlorogenic acid in coffee, anthocyanins in colored fruits, procyanidins in grape seed have become hot research topics in food science and nutrition. There have been thousands of papers on the biochemistry, chemistry, nutritional values and population-based investigations of dietary polyphenols. In this chapter, we reviewed the published articles and database of dietary polyphenols to draw a profile for the classification, structural identification, and biological activities mainly based on enzymes, cell bioassay and animal models, as well as the population-based investigation results. The typical compound and its health benefits for each category of polyphenols was also introduced. The identification of dietary polyphenols could be solved by combined spectroscopy methods, of which the liquid chromatography tandem mass spectrometry is highlighted to greatly increase the efficiency on structural identification. Although the population-based investigation showed some controversial results for health benefits, the multi-functions of dietary polyphenols on preventing metabolic syndromes, various cancers and neurodegenerative disease have attracted much attention.

Fate of polyphenols in forward osmosis

The forward osmosis (FO) is an emerging technique for high quality concentration of liquid foods. Polyphenols are natural compounds with important health function in fruit and vegetable juice. In this study, the impacts of membrane property, feed solution (FS) pH value, draw solution (DS) composition and concentration, and membrane fouling on rejections of 9 food polyphenols by FO were investigated. Polyphenol rejection was mainly dominated by size exclusion and electrostatic repulsion. Membrane with higher negative charge and selectivity exhibited higher rejection. The increased pH of FS could enhance negative charge of membrane and thus increased the rejection. Reverse solute diffusion of DS could also enhance rejection via hindering the forward diffusion of polyphenol. The pectin fouling layer acting as the additional filtration barrier could increase the rejection of most selected polyphenols. However, the rejection of polyphenols with smaller molecular size (less than 23.07 Å2) decreased with the pectin fouled membrane and this might be attributed to the effect of cake-enhanced concentration polarization. The present study revealed the fate of polyphenol in FO and provided vital information to further advance the FO application.

Application of UHPLC-ESI-QTOF-MS in Phytochemical Profiling of Sage (Salvia officinalis) and Rosemary (Rosmarinus officinalis)

AbstractUHPLC with QTOF-MS is widely used as a powerful tool for metabolomic analysis. This technology has recently been applied to the analysis of polyphenols in food and herb extracts. Sage (Salvia officinalis) and rosemary (Rosmarinus officinalis), belonging to the family Lamiaceae, are known for their potent antioxidant properties due to the presence of polyphenols. We have developed a sensitive and reproducible UHPLC-QTOF-MS/MS-based method for comprehensive phytochemical profiling and the identification and quantitation of specific polyphenolic compounds present in sage and rosemary leaves. The herbs were extracted ultrasonically using methanol as the solvent. In sage, rosmarinic acid (17 678.7±673.4 µg/g) and 12-methoxy carnosic acid (21 918.3±715.4 µg/g) were found in the highest concentrations among all polyphenols. In contrast, rosmarinic acid (14 311.0±636.4 µg/g), luteolin-3'-acetyl-O-glucuronide (1488.50±47.58 µg/g), and luteolin-7-O-glucuronide (1053.68±68.83 µg/g) were observed in the highest concentrations in rosemary. Sagerinic acid, rosmanol, rosmadial, carnosol, and carnosic acid were found in abundance in both sage and rosemary. The pentacyclic triterpenoid, corosolic acid ([M - H]¯ m/z 471.35), was detected for the first time in both plants. Of the 47 polyphenolic compounds identified in each plant, 38 compounds were found in common in rosemary and sage. A flavonoid compound, baicalin ([M -H]¯ m/z 445.08), was identified for the first time in S. officinalis. Also, pectolinarigenin ([M - H]¯ m/z 313.07), a dimethoxyflavone, was detected for the first time in both sage and rosemary leaves.

Controlling the Antioxidant Activity of Green Tea Extract through Encapsulation in Chitosan-Citrate Nanogel

Applying bioactive ingredients in the formulation of foods instead of artificial preservatives is problematic because bioactive ingredients are unstable and sensitive to environmental conditions. The present study aimed to control the antioxidant activity of green tea extract (GT) through encapsulating in chitosan nanoparticles (CS-NP). The synthesized nanoparticles were analyzed by using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). The encapsulation efficiency (EE), particle size, zeta potential, and polydispersity index (PDI) of GT-loaded CS-nanoparticles (CS-NP-GT) were assessed. Based on the results, the particle size and zeta potential related to the ratio of CS to GT of 1 : 0.5 were obtained as 135.43 ± 2.52 nm and 40.40 ± 0.2 mV, respectively. Furthermore, the results of FT-IR and XRD confirmed the validity of encapsulating GT in CS-NP. In addition, the antioxidant activity of GT increased after nanoencapsulation since the IC50 value of CS-NP-GT decreased to 6.13 ± 0.12 μg/ml. Finally, applying these particles for delivering GT polyphenols in foods is regarded as promising.