Encapsulation of chrysin and rutin using self-assembled nanoparticles of debranched quinoa, maize, and waxy maize starches

Chrysin and rutin are natural polyphenols with multifaceted biological activities but their applications face challenges in bioavailability. Encapsulation using starch nanoparticles (SNPs) presents a promising approach to overcome the limitations. In this study, chrysin and rutin were encapsulated into self-assembled SNPs derived from quinoa (Q), maize (M), and waxy maize (WM) starches using enzyme-hydrolysis. Encapsulation efficiencies ranged from 74.3 % to 79.1 %, with QSNPs showing superior performance. Simulated in vitro digestion revealed sustained release and higher antioxidant activity in QSNPs compared to MSNPs and WMSNPs. Variations in encapsulation properties among SNPs from different sources were attributed to the differences in the structural properties of the starches. The encapsulated SNPs exhibited excellent stability, retaining over 90 % of chrysin and 85 % of rutin after 15 days of storage. These findings underscore the potential of SNP encapsulation to enhance the functionalities of chrysin and rutin, facilitating the development of fortified functional foods with enhanced bioavailability and health benefits.

Rutin-coated zinc oxide nanoparticles: a promising antivirulence formulation against pathogenic bacteria

The use of engineered nanoparticles against pathogenic bacteria has gained attention. In this study, zinc oxide nanoparticles conjugated with rutin were synthesized and their antivirulence properties against Pseudomonas aeruginosa and Staphylococcus aureus. The physicochemical characteristics of ZnO-Rutin NPs were investigated using SEM, FT-IR, XRD, DLS, EDS, and zeta potential analyses. Antimicrobial properties were evaluated by well diffusion, microdilution, growth curve, and hemolytic activity assays. The expression of quorum sensing (QS) genes including the lasI and rhlI in P. aeruginosa and agrA in S. aureus was assessed using real-time PCR. Swimming, swarming, twitching, and pyocyanin production by P. aeruginosa were evaluated. The NPs were amorphous, 14-100 nm in diameter, surface charge of -34.3 mV, and an average hydrodynamic size of 161.7 nm. Regarding the antibacterial activity, ZnO-Rutin NPs were more potent than ZnO NPs and rutin, and stronger inhibitory effects were observed on S. aureus than on P. aeruginosa. ZnO-Rutin NPs inhibited the hemolytic activity of P. aeruginosa and S. aureus by 93.4 and 92.2%, respectively, which was more efficient than bare ZnO NPs and rutin. ZnO-Rutin NPs reduced the expression of the lasI and rhlI in P. aeruginosa by 0.17-0.43 and 0.37-0.70 folds, respectively while the expression of the agrA gene in S. aureus was decreased by 0.46-0.56 folds. Furthermore, ZnO-Rutin NPs significantly reduced the swimming and twitching motility and pyocyanin production of P. aeruginosa. This study demonstrates the antivirulence features of ZnO-Rutin NPs against pathogenic bacteria which can be associated with their QS inhibitory effects.

Tartary buckwheat protein-phenol conjugate prepared by alkaline-based environment: Identification of covalent binding sites of phenols and alterations in protein structural and functional characteristics

Tartary buckwheat protein-rutin/quercetin covalent complex was synthesized in alkaline oxygen-containing environment, and its binding sites, conformational changes and functional properties were evaluated by multispectral technique and proteomics. The determination of total sulfhydryl and free amino groups showed that rutin/quercetin can form a covalent complex with BPI and could significantly reduce the group content. Ultraviolet-visible spectrum analysis showed that protein could form new characteristic peaks after binding with rutin/quercetin. Circular dichroism spectrum analysis showed that rutin and quercetin caused similar changes in the secondary structure of proteins, both promoting β-sheet to α-helix, β-ture and random coil transformation. The fluorescence spectrometry results showed that the combination of phenols can cause the fluorescence quenching, and the combination of rutin was stronger than the quercetin. Proteomics showed that there were multiple covalent binding sites between phenols and protein. Rutin had a high affinity for arginine, and quercetin and cysteine had high affinity. Meanwhile, the combination of rutin/quercetin and protein had reduced the surface hydrophobic ability of the protein, and improved the foaming, stability and antioxidant properties of the protein. This study expounded the mechanism of the combination of BPI and rutin/quercetin, and analysed the differences of the combination of protein and phenols in different structures. The findings can provide a theoretical basis for the development of complexes in the area of food.

Preparation of rutin imprinted monolith (RIM) by using porogen containing ion liquid [BMIM]PF6 and its molecular recognition

A [BMIM]PF6 ion liquid (IL)-assisted synthesis of a rutin imprinted monolith (RIM) was carried out in an in-situ polymerization method. Bi-functional monomers and a ternary porogen containing IL was used for the RIM preparation and a L9(33) orthogonal factor design performed. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR) and N2 adsorption method was for structural characterization of the RIMs. The monolith was directly used as stationary phase in liquid chromatography to test the retention selectivity, adsorption capacity and extraction application. The optimized porogen consists of 900 μL DMF, 144 μL ACN and 216 μL IL. The monolith RIM-13 obtained under the optimized conditions possessed improved adsorption performance, with a dynamic adsorption capacity of 6.695 mg/g, an imprinting efficiency of 4.841 and a selectivity α value of 4.821. Additionally, this monolith had also higher specific surface area, pore volume and permeability than that obtained without IL and the homogeneity of the imprint sites could be improved by using IL. When the RIM-13 was applied to the separation and purification of rutin from tartary buckwheat, a rutin product with a purity higher than 92 % can be obtained by one cycle. This molecular imprint solid-phase extraction (MI-SPE) is of potency to be applied to preparative-scale separation of other natural products.

[Screening of bioactive components endowing hawthorn with turbidity-eliminating and lipid-lowering functions and development of quality control method of hawthorn]

Hawthorn has the efficacy of eliminating turbidity and lowering the blood lipid level, and it is used for treating hyperlipidemia in clinic. However, the bioactive components of hawthorn are still unclear. In this study, the spectrum-effect relationship was employed to screen the bioactive components of hawthorn in the treatment of hyperlipidemia, and then the bioactive components screened out were verified in vivo. Furthermore, the quality control method for hawthorn was developed based on liquid chromatography-mass spectrometry(LC-MS). The hyperlipidemia model of rats was built, and different polar fractions of hawthorn extracts and their combinations were administrated by gavage. The effects of different hawthorn extract fractions on the total cholesterol(TC), triglycerides(TG), and low-density lipoprotein-cholesterol(LDL-C) in the serum of model rats were studied. The orthogonal projections to latent structures(OPLS) algorithm was used to establish the spectrum-effect relationship model between the 24 chemical components of hawthorn and the pharmacodynamic indexes, and the bioactive components were screened out and verified in vivo. Finally, 10 chemical components of hawthorn, including citric acid and quinic acid, were selected to establish the method for evaluating hawthorn quality based on LC-MS. The results showed that different polar fractions of hawthorn extracts and their combinations regulated the TG, TC, and LDL-C levels in the serum of the model rats. The bioactive components of hawthorn screened by the OPLS model were vitexin-4″-O-glucoside, vitexin-2″-O-rhamnoside, rutin, citric acid, malic acid, and quinic acid. The 10 chemical components of hawthorn, i.e., citric acid, quinic acid, rutin, gallic acid, vitexin-4″-O-glucoside, vitexin-2″-O-rhamnoside, malic acid, vanillic acid, neochlorogenic acid, and fumaric acid were determined, with the average content of 38, 11, 0.018, 0.009 5, 0.037, 0.017, 8.1, 0.009 5, 0.073, and 0.98 mg·g~(-1), respectively. This study provided a scientific basis for elucidating the material basis of hawthorn in treating hyperlipidemia and developed a content determination method for evaluating the quality of hawthorn.

Phenolic structure dependent interaction onto modified goose liver protein enhanced by pH shifting: Modulations on protein interfacial and emulsifying properties

The appropriateness of animal by-product proteins as emulsifiers is barely explored compared to their meat counterparts. This paper focused on improving interfacial and emulsifying properties of modified goose liver protein using three structurally relevant polyphenols either enhanced by pH shifting (P-catechin, P-quercetin and P-rutin) or not (catechin, quercetin and rutin). Due to its high hydrophobicity and limited steric hindrance, quercetin was more sufficient to hydrophobically interact (ΔH > 0, ΔS > 0) with MGLP than catechin and rutin. Results showed that polyphenol interactive affinity was positively correlated to surface hydrophobicity but negatively to size and aggregation extent of MGLP. Interfacial pressure and dilatational elastic modulus implied that synergistic polyphenol interaction and pH shifting favored the interfacial adsorption and macromolecular association of MGLP, particularly for P-quercetin with the values reached to 19.9 ± 2.0 mN/m and 22.9 ± 1.2 mN/m, respectively. Emulsion stabilized by P-quercetin also maintained highest physical and oxidative stabilities regarding the lowest D [4,3] (3.78 ± 0.27 μm) and creaming index (8.38 ± 0.43 %), together with highest mono- (19.51 %) and polyunsaturated fatty acid content (29.39 %) during storage. Overall, chemical structure of polyphenols may be determining in fabricating MGLP-polyphenol complexes with improved emulsion stabilization efficiency.

Unveiling the flavone-solubilizing effects of α-glucosyl rutin and hesperidin: probing structural differences through NMR and SAXS analyses

Flavonoids often exhibit broad bioactivity but low solubility and bioavailability, limiting their practical applications. The transglycosylated materials α-glucosyl rutin (Rutin-G) and α-glucosyl hesperidin (Hsp-G) are known to enhance the dissolution of hydrophobic compounds, such as flavonoids and other polyphenols. In this study, the effects of these materials on flavone solubilization were investigated by probing their interactions with flavone in aqueous solutions. Rutin-G and Hsp-G prepared via solvent evaporation and spray-drying methods were evaluated for their ability to dissolve flavones. Rutin-G had a stronger flavone-solubilizing effect than Hsp-G in both types of composite particles. The origin of this difference in behavior was elucidated by small-angle X-ray scattering (SAXS) and nuclear magnetic resonance analyses. The different self-association structures of Rutin-G and Hsp-G were supported by SAXS analysis, which proved that Rutin-G formed polydisperse aggregates, whereas Hsp-G formed core-shell micelles. The observation of nuclear Overhauser effects (NOEs) between flavone and α-glucosyl materials suggested the existence of intermolecular hydrophobic interactions. However, flavone interacted with different regions of Rutin-G and Hsp-G. In particular, NOE correlations were observed between the protons of flavone and the α-glucosyl protons of Rutin-G. The different molecular association states of Rutin-G or Hsp-G could be responsible for their different effects on the solubility of flavone. A better understanding of the mechanism of flavone solubility enhancement via association with α-glucosyl materials would permit the application of α-glucosyl materials to the solubilization of other hydrophobic compounds including polyphenols such as flavonoids.

An Overview of Biosynthetic Pathway and Therapeutic Potential of Rutin

Flavonoids are compounds abundantly found in nature and known as a polyphenolic group of compounds having flavancore and show the utmost abundant collection of complexes and are found in fiber-rich root vegetables, fruits, and their eatable items. Due to the presence of hydroxyl groups, flavonoids show various therapeutic activities like antioxidant, antibacterial, antiviral, and antiinflammatory. Substituent groups are responsible for the onset of biochemical actions of flavonoids, which affect the metabolism. The major example of flavonol is rutin, which is constituted of rutinose and quercetin. It is a glycosidic type of flavonoid, similarly identified as purple quercitrin and Vitamin P with over 70 plant species and plant-derived foods, exclusively grapefruit, buckwheat seeds, cherries, apricots, grapes, onions, plums, and oranges. Another name forrutin is a citrus flavonoid known as rutoside, and sophorin. Rutin is a polyphenolic compound having a low molecular weight.

Phytochemistry, Bioactivities of Metabolites, and Traditional Uses of Fagopyrum tataricum

In Tartary buckwheat (Fagopyrum tataricum), the edible parts are mainly grain and sprouts. Tartary buckwheat contains protecting substances, which make it possible for plants to survive on high altitudes and under strong natural ultraviolet radiation. The diversity and high content of phenolic substances are important for Tartary buckwheat to grow and reproduce under unfriendly environmental effects, diseases, and grazing. These substances are mainly flavonoids (rutin, quercetin, quercitrin, vitexin, catechin, epicatechin and epicatechin gallate), phenolic acids, fagopyrins, and emodin. Synthesis of protecting substances depends on genetic layout and on the environmental conditions, mainly UV radiation and temperature. Flavonoids and their glycosides are among Tartary buckwheat plants bioactive metabolites. Flavonoids are compounds of special interest due to their antioxidant properties and potential in preventing tiredness, diabetes mellitus, oxidative stress, and neurodegenerative disorders such as Parkinson's disease. During the processing and production of food items, Tartary buckwheat metabolites are subjected to molecular transformations. The main Tartary buckwheat traditional food products are bread, groats, and sprouts.

Binding of Quercetin to Hemoglobin Reduced Hemin Release and Lipid Oxidation

The interactions between quercetin and bovine (or human) hemoglobin (Hb) were systematically investigated by fluorescence, UV-vis absorption spectroscopy, and molecular docking to demonstrate the structural mechanism by which quercetin affected the Hb redox state and stability. Quercetin could interact with the central cavity of the Hb molecule with one binding site to generate an Hb-quercetin complex, and the hydrophobic interaction played an important role in the formation of the complex. The binding constant for the Hb-quercetin complex at 298 K was observed to be 1.25 × 10⁴ M^-1. In addition, quercetin effectively inhibited Hb-induced lipid oxidation in liposomes or washed muscles, which was ascribed to the conversion to oxy-Hb and decreased hemin dissociation from met-Hb. Consistent with its lower abilities to bind Hb and scavenge free radicals, rutin (i.e., quercetin-3-rhamnosylglucsoside) did not significantly influence the redox state of Hb nor reduce hemin release from Hb, and subsequently, it less effectively inhibited Hb-induced lipid oxidation than quercetin. Altogether, the results herein provide novel insights into the antioxidant mechanism for quercetin and are beneficial to the application of natural quercetin in Hb-containing foods.

Rutin hydrate and extract from Castanopsis tribuloides reduces pyrexia via inhibiting microsomal prostaglandin E synthase-1

Castanopsis tribuloides belongs to the oak species (Fagaceae) and it is commonly distributed in evergreen forests of Bangladesh, India, Myanmar, Nepal, China, and Thailand. Our present study aimed at uncovering the antipyretic potential of methanol extract of C. tribuloides bark (CTB) in the mice models. Baker's yeast pyrexia model was employed to determine the antipyretic potentials of the extract. Besides, molecular docking and dynamics simulation of CTB phenolic compounds were explored to validate the experimental results and gain insight into the possible antipyretic mechanism of action that can lead to the design and discovery of novel drugs against mPGES-1. The results revealed that CTB (400 mg/kg) significantly inhibited (P < 0.001) the elevated body temperature of mice since 0.5 h, which is more prominent than the standard. At dose 200 mg/kg, the bark extract also produced significant (P < 0.05) antipyretic activity since 2 h. HPLC-DAD analysis identified and quantified nine polyphenolic compounds from the extract, including rutin hydrate, (-) epicatechin, caffeic acid, catechin hydrate, catechol, trans-ferulic acid, p-coumaric acid, vanillic acid, and rosmarinic acid. Molecular docking study suggested probable competition of these phenolic compounds with glutathione, an essential cofactor for microsomal prostaglandin E synthase-1 (mPGES-1) activity. Additionally, RMSF, RMSD, Rg, and hydrogen bonds performed during MD simulations revealed that rutin hydrate (rich in CTB) bound to the mPGES-1 active site in a stable manner and thus inactivating mPGES-1. Therefore, it can be concluded that rutin hydrate reduces pyrexia in mice via downregulating PGE2 synthesis by inhibiting mPGES-1 activity.

Efficacy Evaluation of Plant Products in the Treatment of Erectile Dysfunction Related to Diabetes

Erectile dysfunction affects more than 50% of diabetic male patients, with a higher prevalence compared with the general population. Age, clinical factors, and lifestyle habits have been suggested to contribute to the pathophysiology and worsening of erectile dysfunction in diabetic patients. First- and second-line standard treatments are represented by phosphodiesterase type 5 (PDE5) inhibitors and alprostadil, respectively. However, natural compounds have been suggested to ameliorate this clinical condition. This study aims to preclinically characterize the potential synergism among plant-derived products for the improvement of erectile dysfunction in the diabetic condition. The effects of a nutritional supplement composed of Panax ginseng, Moringa oleifera and rutin, as single agents or as a mixture, were evaluated in a streptozotocin (STZ)-induced diabetic rat model with erectile dysfunction. The treatment efficacy was evaluated by measuring sexual-related parameters (i.e., mount and intromission latencies, the mount and intromission frequencies and the ejaculation latency). Results showed that only the mixture was able to significantly reduce the diabetes-related delay in mount latency (p < 0.01). Substantial similar effects were observed by measuring the intromission latency and the mean number of mounts was very similar between rats treated with the mixture and controls. Single agent treatments showed very low effects in terms of intromission frequency, whereas the mixture was able to increase this parameter. Additionally, a statistically significant reduced ejaculation latency was observed in rats treated with the mixture compared with the STZ control. These results are in agreement with the available literature and suggest that the study mixture may ameliorate sexual behavior compared with the administration of the study natural compounds as single agents in diabetic rats. Further preclinical and clinical studies are needed to perform a more comprehensive evaluation of the efficacy and safety of the study mixture.

Composition and content of phenolic acids and flavonoids among the different varieties, development stages, and tissues of Chinese Jujube (Ziziphus jujuba Mill.)

The composition and content of phenolic acids and flavonoids among the different varieties, development stages, and tissues of Chinese jujube (Ziziphus jujuba Mill.) were systematically examined using ultra-high-performance liquid chromatography to provide a reference for the evaluation and selection of high-value resources. Five key results were identified: (1) Overall, 13 different phenolic acids and flavonoids were detected from among the 20 excellent jujube varieties tested, of which 12 were from the fruits, 11 from the leaves, and 10 from the stems. Seven phenolic acids and flavonoids, including (+)-catechin, rutin, quercetin, luteolin, spinosin, gallic acid, and chlorogenic acid, were detected in all tissues. (2) The total and individual phenolic acids and flavonoids contents significantly decreased during fruit development in Ziziphus jujuba cv.Hupingzao. (3) The total phenolic acids and flavonoids content was the highest in the leaves of Ziziphus jujuba cv.Hupingzao, followed by the stems and fruits with significant differences among the content of these tissues. The main composition of the tissues also differed, with quercetin and rutin present in the leaves; (+)-catechin and rutin in the stems; and (+)-catechin, epicatechin, and rutin in the fruits. (4) The total content of phenolic acid and flavonoid ranged from 359.38 to 1041.33 μg/g FW across all examined varieties, with Ziziphus jujuba cv.Jishanbanzao having the highest content, and (+)-catechin as the main composition in all 20 varieties, followed by epicatechin, rutin, and quercetin. (5) Principal component analysis showed that (+)-catechin, epicatechin, gallic acid, and rutin contributed to the first two principal components for each variety. Together, these findings will assist with varietal selection when developing phenolic acids and f lavonoids functional products.

Protective effects of rutin and chlorogenic acid against antihypoxic conditions in mice

Almost all plants contain polyphenols. Literature shows that polyphenols exhibit many biological activities. Little has known about their protective effects against hypoxia-induced lethality. The protective effects of rutin (1) and chlorogenic acid (2) against hypoxia conditions in mice were determined by three different experimental models. Antihypoxic activity was especially pronounced in asphytic hypoxia. Both compounds (1&2) showed statistically significant (p>0.05) activities respect to the control. Compound (1) significantly prolonged the latency for death with respect to control (39.20±8.70 vs. 13.20±2.58min, p<0.001). Compound (1) was the most effective compound in circulatory hypoxia. It significantly prolonged the latency for death with respect to control (14.44±2.82 vs. 9.82±0.79 min, p<0.01). On the other hand, Chlorogenic acid (2) at a dose of 100 mg kg^-1 kept mice alive for 12.76±1.30min (p>0.05). None of two phenolic acids had any activity in haemic hypoxia when compared to control.

Fatty Acid Analysis, Chemical Constituents, Biological Activity and Pesticide Residues Screening in Jordanian Propolis

Propolis is a resinous natural product collected by honeybees (Apis mellifera and others) from tree exudates that has been widely used in folk medicine. The present study was carried out to investigate the fatty acid composition, chemical constituents, antioxidant, and xanthine oxidase (XO) inhibitory activity of Jordanian propolis, collected from Al-Ghour, Jordan. The hexane extract of Jordanian propolis contained different fatty acids, which are reported for the first time by using GC-FID. The HPLC was carried out to identify important chemical constituents such as fatty acids, polyphenols and α-tocopherol. The antioxidant and xanthine oxidase inhibitory activities were also monitored. The major fatty acid identified were palmitic acid (44.6%), oleic acid (18:1∆⁹cis, 24.6%), arachidic acid (7.4%), stearic acid (5.4%), linoleic acid (18:2∆^9–12cis, 3.1%), caprylic acid (2.9%), lignoceric acid (2.6%), cis-11,14-eicosaldienoic acid (20:2∆^11–14cis, 2.4%), palmitoleic acid (1.5%), cis-11-eicosenoic acid (1.2%), α–linolenic acid (18:3∆^9–12–15cis, 1.1%), cis-13,16-docosadienoic acid (22:2∆^13–16cis, 1.0%), along with other fatty acids. The major chemical constituents identified using gradient HPLC-PDA analysis were pinocembrin (2.82%), chrysin (1.83%), luteolin-7-O-glucoside (1.23%), caffeic acid (1.12%), caffeic acid phenethyl ester (CAPE, 0.79%), apigenin (0.54%), galangin (0.46%), and luteolin (0.30%); while the minor constituents were hesperidin, quercetin, rutin, and vanillic acid. The percentage of α-tocopherol was 2.01 µg/g of the lipid fraction of propolis. Antioxidant properties of the extracts were determined via DPPH radical scavenging. The DPPH radical scavenging activities (IC₅₀) of different extracts ranged from 6.13 to 60.5 µg/mL compared to ascorbic acid (1.21 µg/mL). The xanthine oxidase inhibition (IC₅₀) ranged from 75.11 to 250.74 µg/mL compared to allopurinol (0.38 µg/mL). The results indicate that the various flavonoids, phenolic compounds, α-tocopherol, and other constituents which are present in propolis are responsible for the antioxidant and xanthine oxidation inhibition activity. To evaluate the safety studies of propolis, the pesticide residues were also monitored by LC-MS-MS 4500 Q-Trap. Trace amounts of pesticide residue (ng/mL) were detected in the samples, which are far below the permissible limit as per international guidelines.

Antiviral Activity of Metabolites from Peruvian Plants against SARS-CoV-2: An In Silico Approach

(1) Background: The COVID-19 pandemic lacks treatments; for this reason, the search for potential compounds against therapeutic targets is still necessary. Bioinformatics tools have allowed the rapid in silico screening of possible new metabolite candidates from natural resources or repurposing known ones. Thus, in this work, we aimed to select phytochemical candidates from Peruvian plants with antiviral potential against three therapeutical targets of SARS-CoV-2. (2) Methods: We applied in silico technics, such as virtual screening, molecular docking, molecular dynamics simulation, and MM/GBSA estimation. (3) Results: Rutin, a compound present in Peruvian native plants, showed affinity against three targets of SARS-CoV-2. The molecular dynamics simulation demonstrated the high stability of receptor-ligand systems during the time of the simulation. Our results showed that the Mpro-Rutin system exhibited higher binding free energy than PLpro-Rutin and N-Rutin systems through MM/GBSA analysis. (4) Conclusions: Our study provides insight on natural metabolites from Peruvian plants with therapeutical potential. We found Rutin as a potential candidate with multiple pharmacological properties against SARS-CoV-2.

Electrospun chitosan oligosaccharide/polycaprolactone nanofibers loaded with wound-healing compounds of Rutin and Quercetin as antibacterial dressings

Burn injury has posed devastating burdens on the public health due to its inevitable damage to the skin structure resulting in the increased risk of infection. Therefore, it is highly demanding to develop efficacious antibacterial wound-healing dressing. Despite the favourable wound-healing activities, the curative efficacy of phytochemical compounds of quercetin (Qe) and its derivatives is limited by their poor water solubility. Here, we have fabricated a novel electrospun nanofiber membrane (ENM) consisting of polycaprolactone (PCL), chitosan oligosaccharides (COS), and Qe/Rutin (Ru) as the potential bioactive dressing for wound healing. The incorporation of chitosan oligosaccharides (COSs) in the PCL scaffold at the optimized molar ratio not only contributed to the improved hydrophilicity and water absorption performance of the ENM but effectively increased the specific surface area of the formed nanofibers. In particular, the antioxidant and antibacterial activities of the Qe/rutin-loaded nanofiber membranes were tested, which revealed that the PCL-COS-Qe membrane exhibited superior performance among all nanofiber membranes. Therefore, the developed PCL-COS-Qe/Ru nanofiber membranes hold enormous potential as healthcare products, such as wound dressings for burn injuries.

Sulfation of Quercitrin, Epicatechin and Rutin by Human Cytosolic Sulfotransferases (SULTs): Differential Effects of SULT Genetic Polymorphisms

Radix Bupleuri is one of the most widely used herbal medicines in China for the treatment of fever, pain, and/or chronic inflammation. Quercitrin, epicatechin, and rutin, the flavonoids present in Radix Bupleuri, have been reported to display anti-inflammatory, antitumor, and antioxidant biological activities among others. Sulfation has been reported to play an important role in the metabolism of flavonoids. In this study, we aimed to systematically identify the human cytosolic sulfotransferase enzymes that are capable of catalyzing the sulfation of quercitrin, epicatechin, and rutin. Of the thirteen known human cytosolic sulfotransferases, three (cytosolic sulfotransferase 1A1, cytosolic sulfotransferase 1C2, and cytosolic sulfotransferase 1C4) displayed sulfating activity toward quercitrin, three (cytosolic sulfotransferase 1A1, cytosolic sulfotransferase 1A3, and cytosolic sulfotransferase 1C4) displayed sulfating activity toward epicatechin, and six (cytosolic sulfotransferase 1A1, cytosolic sulfotransferase 1A2, cytosolic sulfotransferase 1A3, cytosolic sulfotransferase 1B1, cytosolic sulfotransferase 1C4, and cytosolic sulfotransferase 1E1) displayed sulfating activity toward rutin. The kinetic parameters of the cytosolic sulfotransferases that showed the strongest sulfating activities were determined. To investigate the effects of genetic polymorphisms on the sulfation of quercitrin, epicatechin, and rutin, individual panels of cytosolic sulfotransferase allozymes previously prepared were analyzed and shown to display differential sulfating activities toward each of the three flavonoids. Taken together, these results provided a biochemical basis underlying the metabolism of quercitrin, epicatechin, and rutin through sulfation in humans.

Phytochemistry, antioxidant and antibacterial activities of fruit extracts of Myrsine africana L

Myrsine africana L. a commonly consumed medicinal plant grows in forest of mountains region located at North East of Pakistan. In current study, the fruit extracts were chemically characterized and their bioactivities were determined. Higher quantity of total phenols, total flavonoids and tannins were obtained from methanolic fruit extracts. The HPLC analysis provided higher level of quercetin followed by rutin and p-coumaric acid. Whereas the GC-MS quantification had given significant level of ten saturated and unsaturated fatty acids and some of them were not reported earlier. In vitro study, lower cytotoxic behavior of fruit extracts but higher antioxidant values as well as higher zone of inhibition versus S. aureus, E. coli, K. pneumonia and B. subtilis and Mycobacterium tuberculosis were observed. The organic compounds found in fruit extracts of M. africana correlated well with its used in ethno medicines.

Alkaloid and phenolic compounds of Xylopia aromatica inhibits tumor growth by down-regulating matrix metalloproteinase-2 (MMP-2) expression

Annonacea species have been reported to possess antitumor properties. However, the in vitro and in vivo antitumor activities of Xylopia aromatica (Annonacea) have not yet been elucidated. This study aimed to investigate the effects of Xylopia aromatica leaves hexane fraction (XaHF) on Ehrlich ascites carcinoma cells lines (EAC), both in vitro and in vivo. In vitro assays revealed a significant cytotoxic effect with the two lower XaHF concentrations (62.5 and 32.3mg/mL). EAC (2.5x10⁶ cells) were inoculated in the right flank of Swiss mice, and the animals were treated intraperitoneally with 32.3mg kg^-1 of XaHF daily, for 20 days. Our findings indicate that XaHF suppressed the growth of EAC in vivo, with a significant decrease (46%) in tumor volume. There was also a decrease in the necrosis area (71%), inflammatory infiltrate, and MMP-2 expression. High-Performance Liquid Chromatography with Diode Array Detector (HPLC-DAD) identified secondary metabolites possibly related to phenolic acids, flavonoids, and alkaloids. Thus, the results confirmed the antitumoral activity that may be related to the presence of the identified metabolites in XaHF extract.

Anti-MRSA Constituents from Ruta chalepensis (Rutaceae) Grown in Iraq, and In Silico Studies on Two of Most Active Compounds, Chalepensin and 6-Hydroxy-rutin 3',7-Dimethyl ether

Ruta chalepensis L. (Rutaceae), a perennial herb with wild and cultivated habitats, is well known for its traditional uses as an anti-inflammatory, analgesic, antipyretic agent, and in the treatment of rheumatism, nerve diseases, neuralgia, dropsy, convulsions and mental disorders. The antimicrobial activities of the crude extracts from the fruits, leaves, stem and roots of R. chalepensis were initially evaluated against two Gram-positive and two Gram-negative bacterial strains and a strain of the fungus Candida albicans. Phytochemical investigation afforded 19 compounds, including alkaloids, coumarins, flavonoid glycosides, a cinnamic acid derivative and a long-chain alkane. These compounds were tested against a panel of methicillin-resistant Staphylococcus aureus (MRSA) strains, i.e., ATCC 25923, SA-1199B, XU212, MRSA-274819 and EMRSA-15. The MIC values of the active compounds, chalepin (9), chalepensin (10), rutamarin (11), rutin 3′-methyl ether (14), rutin 7,4′-dimethyl ether (15), 6-hydroxy-rutin 3′,7-dimethyl ether (16) and arborinine (18) were in the range of 32–128 µg/mL against the tested MRSA strains. Compounds 10 and 16 were the most active compounds from R. chalepensis, and were active against four out of six tested MRSA strains, and in silico studies were performed on these compounds. The anti-MRSA activity of compound 16 was comparable to that of the positive control norfloxacin (MICs 32 vs 16 μg/mL, respectively) against the MRSA strain XU212, which is a Kuwaiti hospital isolate that possesses the TetK tetracycline efflux pump. This is the first report on the anti-MRSA property of compounds isolated from R. chalepensis and relevant in silico studies on the most active compounds.

Preparation of rutin-loaded microparticles by debranched lentil starch-based wall materials: Structure, morphology and in vitro release behavior

Different treatments of autoclaving, pullulanase debranching and/or ultrasound were applied to prepare debranched lentil starch (DBLS). Their fine structures can affect the retrogradation patterns of DBLSs, which consequently could affect their potential use as delivery carrier of sensitive bioactive compounds. An attempt was made to use these DBLSs as wall materials to encapsulate rutin, aiming to improve the bioaccessibility, meanwhile to enhance the aqueous solubility and stability of rutin molecules. Their encapsulation efficiency, structural characteristics, thermal stability, morphological features, antioxidant activity and in vitro release behavior under simulated upper gastrointestinal tract environment were evaluated. The results suggested that rutin was dispersed in the DBLS polymer matrix, showing the amorphous nature that further authenticates the encapsulation and entrapment of rutin. The structural analyses of microparticles revealed that rutin could interacted with DBLS biopolymer chains by hydrogen bonds, making the starch molecular chains less susceptible to interact with themselves for reordering. The encapsulation efficiency was found to be in an opposite trend with those values obtained for relative crystallinity, melting enthalpy, degree of order/double helices of DBLS wall materials before encapsulation. The release rate results indicated that DBLS carrier with lower M_w, DP_n and higher molecular order was beneficial for the slower release of rutin encapsulated in the microparticles.

Drying Techniques and Storage: Do They Affect the Nutritional Value of Bee-Collected Pollen?

In this study, the effect of different drying processes (freeze-drying (FD), microwave-assisted drying (MWD) and classic hot air drying (HAD)) on the polyphenols, flavonoids, and amino acids content was investigated on bee-collected chestnut, willow and ivy pollen for human consumption. Furthermore, the pollen chemical properties were monitored after three and six months of storage, and then analyzed using a multivariate approach. Chestnut pollen was the richest source of polyphenols, flavonoids, and rutin, while ivy pollen contained the highest amount of total and free amino acids, and total and free proline. Drying and storage affected pollen chemical composition with species-dependent effects. MWD allowed the best retention of flavonoids in chestnut pollen for up to six months of storage. All drying techniques led to a depletion of flavonoids in willow pollen; however, MWD ensured the highest flavonoids content after six months. FD and MWD did not lead to flavonoids depletion in ivy pollen during storage. Additionally, storage did not affect the rutin content, which was highest in FD willow samples after six months. Notably, both FD and MWD techniques are efficient in preserving amino acids-related quality of bee pollen up to six months of storage.

Evaluation of Structurally Different Ionic Liquid-Based Surfactants in a Green Microwave-Assisted Extraction for the Flavonoids Profile Determination of Mangifera sp. and Passiflora sp. Leaves from Canary Islands

Aqueous solutions of ionic liquids (ILs) with surface active properties were used as extraction solvents, taking advantage of their impressive solvation properties, in a green microwave-assisted solid-liquid extraction method (IL-MA-SLE) for the extraction of flavonoids from passion fruit and mango leaves. The extraction method was combined with high-performance liquid chromatography and photodiode-array detection (HPLC-PDA) and optimized by response surface methodology using the Box-Behnken experimental design. Under optimum conditions, the extraction efficiency of six structurally different IL-based surfactants was evaluated. Thus, imidazolium-, guanidinium- and pyridinium-type ILs with different tailorable characteristics, such as side chain length and multicationic core, were assessed. The decylguanidinium chloride ([C10Gu+][Cl-]) IL-based surfactant was selected as key material given its superior performance and its low cytotoxicity, for the determination of flavonoids of several samples of Passiflora sp. and Mangifera sp. leaves from the Canary Islands, and using as target analytes: rutin, quercetin and apigenin. The analysis of 50 mg of plant material only required 525 µL of the low cytotoxic IL-based surfactant solution at 930 mM, 10.5 min of microwave irradiation at 30 °C and 50 W, which involves a simpler, faster, more efficient and greener method in comparison with other strategies reported in the literature for obtaining bioactive compounds profiles from plants.

Topical Application of Aronia melanocarpa Extract Rich in Chlorogenic Acid and Rutin Reduces UVB-Induced Skin Damage via Attenuating Collagen Disruption in Mice

Aronia melanocarpa, a black chokeberry, contains high levels of phenolic acids and polyphenolic flavonoids and displays antioxidative and anti-inflammatory effects. Through high-performance liquid chromatography for extracts from Aronia melanocarpa, we discovered that the extract contained chlorogenic acid and rutin as major ingredients. In this study, we examined the protective effects of the extract against ultraviolet B- (UVB)-induced photodamage in the dorsal skin of institute of cancer research (ICR) mice. Their dorsal skin was exposed to UVB, thereafter; the extract was topically applied once a day for seven days. Photoprotective properties of the extract in the dorsal skin were investigated by clinical skin severity score for skin injury, hematoxylin and eosin staining for histopathology, Masson's trichrome staining for collagens. In addition, we examined change in collagen type I and III, and matrix metalloproteinase (MMP)-1 and MMP-3 by immunohistochemistry. In the UVB-exposed mice treated with the extract, UVB-induced epidermal damage was significantly ameliorated, showing that epidermal thickness was moderated. In these mice, immunoreactivities of collagen type I and III were significantly increased, whereas immunoreactivities of MMP-1 and 3 were significantly decreased compared with those in the UVB-exposed mice. These results indicate that treatment with Aronia melanocarpa extract attenuates UV-induced photodamage by attenuating UVB-induced collagen disruption: these findings might be a result of the chlorogenic acid and rutin contained in the extract. Based on the current results, we suggest that Aronia melanocarpa can be a useful material for developing photoprotective adjuvant.

Antiviral Properties of Flavonoids and Delivery Strategies

This review summarizes the latest advancements in phytochemicals as functional antiviral agents. We focused on flavonoids, like apigenin, vitexin, quercetin, rutin and naringenin, which have shown a wide range of biological effects including antiviral activities. The molecular mechanisms of their antiviral effects mainly consist in the inhibition of viral neuraminidase, proteases and DNA/RNA polymerases, as well as in the modification of various viral proteins. Mixtures of different flavonoids or combination of flavonoids with antiviral synthetic drugs provide an enhancement of their antiviral effects. Recent strategies in drug delivery significantly contribute to overcoming the low bioavailability of flavonoids. Frequent viral infections worldwide have led to the need for new effective antiviral agents, which can be identified among the various phytochemicals. In this light, screening the antiviral activities of a cocktail of flavonoids would be advantageous in order to prevent viral infections and improve current antiviral therapies.

Poziotinib and bovine serum albumin binding characterization and influence of quercetin, rutin, naringenin and sinapic acid on their binding interaction

Serum albumin is the major transporter protein present in systemic circulation and the ability to transport ligands can be influenced in presence of other ligands. This interaction can influence the pharmacodynamic and pharmacokinetic property of certain ligands. Spectroscopic and molecular docking studies were conducted to understand the poziotinib binding interaction to bovine serum albumin (BSA). Further, influence of different flavonoids (quercetin, rutin, naringenin and sinapic acid) on displacing poziotinib from BSA binding sites was also studied. The BSA and poziotinib followed a static quenching mechanism as the Stern-Volmer constant showed decrease (7.6 × 10⁴-6.0 × 10⁴) when the temperature increased from 298 K to 310 K. The BSA and poziotinib interaction was spontaneous and enthalpy driven. Involvement of Van der Waals forces and hydrogen bonding in the binding interaction was suggested on the basis of thermodynamic study results. Conformational changes were suggested in the BSA on its interaction with poziotinib based on fluorescence experimental data. The binding constant for BSA-poziotinib showed a maximum decrease in presence of quercetin followed by naringenin, rutin and sinapic acid respectively. Site displacement studies suggested binding of poziotinib site I of BSA.

Hydromethanolic Extracts from Adansonia digitata L. Edible Parts Positively Modulate Pathophysiological Mechanisms Related to the Metabolic Syndrome

Metabolic syndrome includes a cluster of risk factors for many pathological conditions, including hyperglycemia, abdominal obesity, hyperlipidemia, and hypertension. Adansonia digitata L. (also known as baobab) is used in traditional African Medicine and recent studies showed that it improves the metabolism of carbohydrates and lipids. The aim of this study is to investigate the mechanisms of action associated with the beneficial effects of extracts from the edible parts of baobab (fruit pulp, leaves, raw and toasted seeds), evaluating their inhibitory activity against: alpha-amylase, alpha-glucosidase, angiotensin-converting enzyme, 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase, and pancreatic lipase. Baobab fruit pulp and leaf extracts resulted to be the most active ones and were then tested on the differentiation process of SW-872 human liposarcoma cells to mature adipocytes. The addition of these latter extracts did not affect triglyceride accumulation, indicating a neutral impact on this parameter. The findings here reported help to explain the growing amount of evidence on the biological properties of baobab and provide suggestions about their use in food and nutraceutical fields.

A High-matched Melamine Sensor Using Core/shell Nano Particles of Fe3O4@Polyrutin-COOH and Ionic Liquid as Imprinted Polymeric Monomers

We describe here a magnetic molecular imprinted polymeric ionic liquid (MMIPIL) film by using a functionalized ionic liquid (3-vinyl-4-amino-5-imidazole carboxamide chloride, IL) and Fe3O4@Polyrutin-COOH as a functional monomer and supporting materials. The change in the direction of the charge density in the structure of MMIPIL polymer resulted in a red shift of about 100 nm for the characteristic group of -C=O. Polyrutin containing an electron-rich benzene ring and multiple hydroxyl groups not only prevented the aggregation of Fe3O4, but also benefitted to immobilize template molecules. More symmetric amino groups in the template molecules generated more hydrogen bonds and other synergistic effects between MEL and the functional monomers, which resulted in a highly-matched and highly stable MMIPIL sensor. The proposed magnetic sensor lowered the matching potential, and enhanced the signal for the detection of melamine (MEL) in milk powder. Under the optimum conditions, the MEL template molecule showed a significant linear relationship between 5.0 × 10-3 and 0.8 μg/L with a detection limit (S/N = 3) of 1.5 × 10-3 μg/L. The MMIPIL sensor showed wonderful selectivity and exhibited facile, fast and efficient results in the monitoring MEL with recoveries of between 96.5 and 108.3%.

Separation and characterization of unknown impurities in rutin tablets using trap-free two-dimensional liquid chromatography coupled with ion trap/time-of-flight mass spectrometry

RATIONALE

A new high-performance liquid chromatography method was developed for the determination of impurities in rutin tablets to improve on the method of the official monograph in national drug standards. Five impurities in rutin tablets were characterized using trap-free two-dimensional liquid chromatography coupled with ion trap/time-of-flight mass spectrometry (2D-LC/IT-TOFMS) in both positive and negative ion modes of electrospray ionization.

METHODS

In the first dimension, the LC column was a Thermo Acclaim 120™ C18 (4.6 mm × 250 mm, 5 μm), and the mobile phase was composed of 0.1 M sodium dihydrogen phosphate aqueous solution (pH adjusted to 4.4 with phosphoric acid) and acetonitrile (80:20, v/v). In the second dimension, the column was a Shimadzu Shim-pack GISS C18 (50 mm × 2.1 mm, 1.9 μm), and the mobile phase was composed of 10 mM ammonium formate solution and methanol.

RESULTS

The structures of five impurities in rutin tablets were deduced based on the MS ⁿ data in both positive and negative ion modes, in which two impurities were unknown. Impurity 1, impurity 2 and impurity 3 were proposed as flavonol 3,7-di-O-glycoside, flavonol mono-O-triglycoside and quercetin 3-O-glycoside, respectively, and impurity 4 and impurity 5 were proposed as kaempferol 3-O-rhamnosylglucoside and isorhamnetin 3-O-rhamnosylglucoside, respectively.

CONCLUSIONS

The method established in this study was simple and reliable for the routine quality control of rutin tablets. The contradiction between non-volatile salt mobile phase and mass spectrometry was solved by means of a multiple heart-cutting 2D-LC approach and on-line desalination technology. Five impurities were separated and characterized. These results provide a scientific basis for further improving the national drug standard of rutin tablets.

Formation of glyco-functionalized interfaces for protein binding using polyphenolic glycoside

In this study, a polyphenolic glycoside (α-glucosyl rutin) was used to form glyco-functionalized interfaces for protein binding. α-Glucosyl rutin was coated onto precious metals, metal oxides, and synthetic polymers, including polyethylene and polytetrafluoroethylene with poor surface modifiability. The glyco-functionalized interfaces bound strongly and specifically to concanavalin A and Bauhinia purpurea lectin, which have different carbohydrate specificities. Competitive adsorption tests demonstrated that the binding sites for the abovementioned lectins were glucosyl and rhamnosyl residues, respectively. The glyco-functionalized interfaces maintained the protein binding ability after being stored in aqueous solution for 1 day and in air for 160 days. Once the glyco-functionalized interfaces were formed on gold, silicon dioxide, polystyrene, and polytetrafluoroethylene using α-glucosyl rutin, all the glyco-functionalized interfaces bound to concanavalin A rather than peanut agglutinin.

Phenolic Compounds, Antioxidant Activities, and Inhibitory Effects on Digestive Enzymes of Different Cultivars of Okra (Abelmoschus esculentus)

In this study, the phenolic profiles and bioactivities of five representative cultivars of okra collected in China were investigated. Noticeable variations of phenolic compounds and their bioactivities were observed among these different cultivars of okra. The contents of total flavonoids (TFC) in “Shuiguo”, “Kalong 8”, “Kalong 3”, “Wufu”, and “Royal red” ranged from 1.75 to 3.39 mg RE/g DW, of which “Shuiguo” showed the highest TFC. Moreover, five individual phenolic compounds were found in okra by high performance liquid chromatography analysis, including isoquercitrin, protocatechuic acid, quercetin-3-O-gentiobioside, quercetin, and rutin, while isoquercitrin and quercetin-3-O-gentiobioside were detected as the main phenolic compounds in okra. Moreover, all tested okra exhibited significant antioxidant activities (2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity, 2,2’-azino-bis (3-ethylenzthiazoline-6-sulphonic acid) radical scavenging capacity, and ferric reducing antioxidant power) and inhibitory effects on digestive enzymes (lipase, α-glucosidase, and α-amylase). Indeed, “Shuiguo” exhibited much better antioxidant activities and inhibitory activities on digestive enzymes, which might be attributed to its high TFC. Results suggested that okra, especially “Shuiguo”, could be developed as natural antioxidants and inhibitors against hyperlipidemia and hyperglycemia in the fields of functional foods and pharmaceuticals, which could meet the increasing demand for high-quality okra with health-promoting properties in China.

Anticancer Activity of Rutin and Its Combination with Ionic Liquids on Renal Cells

The renal cell carcinoma (RCC) is the most common type of kidney cancer. Identifying novel and more effective therapies, while minimizing toxicity, continues to be fundamental in curtailing RCC. Rutin, a bioflavonoid widely found in nature, has shown promising anticancer properties, but with limited applicability due to its poor water solubility and pharmacokinetics. Thus, the potential anticancer effects of rutin toward a human renal cancer cell line (786-O), while considering its safety in Vero kidney cells, was assessed, as well as the applicability of ionic liquids (ILs) to improve drug delivery. Rutin (up to 50 µM) did not show relevant cytotoxic effects in Vero cells. However, in 786-O cells, a significant decrease in cell viability was already observed at 50 µM. Moreover, exposure to rutin caused a significant increase in the sub-G1 population of 786-O cells, reinforcing the possible anticancer activity of this biomolecule. Two choline-amino acid ILs, at non-toxic concentrations, enhanced rutin’s solubility/loading while allowing the maintenance of rutin’s anticancer effects. Globally, our findings suggest that rutin may have a beneficial impact against RCC and that its combination with ILs ensures that this poorly soluble drug is successfully incorporated into ILs–nanoparticles hybrid systems, allowing controlled drug delivery.

Structural Changes of Sarco/Endoplasmic Reticulum Ca2+-ATPase Induced by Rutin Arachidonate: A Molecular Dynamics Study

Sarco/endoplasmic reticulum Ca²⁺-ATPase (SERCA) maintains the level of calcium concentration in cells by pumping calcium ions from the cytoplasm to the lumen while undergoing substantial conformational changes, which can be stabilized or prevented by various compounds. Here we attempted to clarify the molecular mechanism of action of new inhibitor rutin arachidonate, one of the series of the acylated rutin derivatives. We performed molecular dynamics simulations of SERCA1a protein bound to rutin arachidonate positioned in a pure dipalmitoylphosphatidylcholine bilayer membrane. Our study predicted the molecular basis for the binding of rutin arachidonate towards SERCA1a in the vicinity of the binding site of calcium ions and near the location of the well-known inhibitor thapsigargin. The stable hydrogen bond between Glu771 and rutin arachidonate plays a key role in the binding. SERCA1a is kept in the E2 conformation preventing the formation of important salt bridges between the side chains of several residues, primarily Glu90 and Lys297. All in all, the structural changes induced by the binding of rutin arachidonate to SERCA1a may shift proton balance near the titrable residues Glu771 and Glu309 into neutral species, hence preventing the binding of calcium ions to the transmembrane binding sites and thus affecting calcium homeostasis. Our results could lead towards the design of new types of inhibitors, potential drug candidates for cancer treatment, which could be anchored to the transmembrane region of SERCA1a by a lipophilic fatty acid group.

Rutin ameliorates mercuric chloride-induced hepatotoxicity in rats via interfering with oxidative stress, inflammation and apoptosis

OBJECTIVE

Mercury is a global environmental pollutant and is responsible for several organ pathophysiology including oxidative stress-induced liver disorders. Therefore, the present study was conducted to evaluate the potential ameliorative effects of rutin on mercury chloride (HgCl₂)-induced hepatotoxicity in adult male rats.

METHODS

HgCl₂ was intraperitoneally injected at a dose of 1.23 mg/kg body weight for 7 days alone or in combination with the orally rutin (50 and 100 mg/kg body weight).

RESULTS

Rutin treatment significantly improved liver function tests [alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine aminotransferase (ALT)], and increased activities of antioxidant defense system [catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx)] and glutathione (GSH) content. The histological alterations and epidermal growth factor receptor (EGFR) expression in the HgCl₂-induced liver tissues were decreased by administration of rutin. Furthermore, rutin reversed the changes in levels of apoptosis and inflammation related proteins involving p53, Bcl-2 associated X protein (Bax), B-cell lymphoma-2 (Bcl-2), cytochrome c, nuclear factor kappa B (NF-κB), tumor necrosis factor-α (TNF-α), B-cell lymphoma-3(Bcl-3) and interleukin-1β (IL-1β), and inhibited p38α mitogen-activated protein kinase (MAPK) and cysteine aspartate specific protease-3 (caspase-3) activations.

CONCLUSION

The data of the present study suggest that rutin effectively suppress HgCl₂-induced hepatotoxicity by ameliorating oxidative stress, inflammation and apoptosis.

Impact of Pickering Intervention on the Stability of W1/O/W2 Double Emulsions of Relevance to Foods

Although water-in-oil-in-water (W₁/O/W₂) double emulsions have been associated with a spectrum of potential applications in foods, their complex microstructure is significantly unstable. Pickering stabilization, reputed for superior and longer-term interfacial stabilization when compared to surfactant-stabilized systems, could provide the opportunity to enhance double-emulsion stability. The current work presents a systematic study on the impact of progressively adopting such a Pickering intervention onto one or both interfaces of W₁/O/W₂ emulsions relevant to foods. A range of surfactants/emulsifiers and particles have been used at the W₁/O or O/W₂ interface of the W₁/O/W₂ microstructure and, where appropriate, cross-compared with the equivalent interfaces of simple emulsions (W/O and O/W, respectively). As the aqueous compartments of all investigated systems were not osmotically balanced (at the point of formulating/forming these), any advantages in terms of double-emulsion stability enhancement can be directly attributed to the employed particle stabilization. It is demonstrated that, although partial Pickering intervention can encourage stability (particularly if that is introduced at the inner W₁/O interface), only complete Pickering stabilization of the double microstructure can ensure that the oil globule size is maintained and the internal water phase is retained over a storage period of one month.

Preparation, Evaluation and Characterization of Rutin-Chitooligosaccharide Complex

Rutin possesses a wide range of application prospects with various bioactivities. However, its bitter and water-insoluble properties restrict its application in the field of functional foods. A new complex of rutin and chitooligosaccharide (Rutin-COS) was prepared via spray-drying method (100 °C, 1 L/h) and freeze-drying method (-80 °C, 24 h), respectively. The water solubility, bitterness, antioxidant and antibacterial activities of Rutin-COS were evaluated, and the complexation of Rutin-COS was characterized by SEM, ¹H-NMR and ROESY. Compared to freeze-drying method, spray-drying method was more effective for preparing stable Rutin-COS complex. The spray-dried Rutin-COS showed increased water solubility, weakened bitterness, enhanced antioxidant and antibacterial activity compared to rutin. The Rutin-COS complex was demonstrated to be formed through hydrogen bonds between the A, B rings of rutin and COS.

Hypoglycemic, Antiglycation, and Cytoprotective Properties of a Phenol-Rich Extract From Waste Peel of Punica granatum L. var. Dente di Cavallo DC2

Pomegranate peel is a natural source of phenolics, claimed to possess healing properties, among which are antioxidant and antidiabetic. In the present study, an ethyl acetate extract, obtained by Soxhlet from the peel of Dente di Cavallo DC2 pomegranate (PGE) and characterized to contain 4% w/w of ellagic acid, has been evaluated for its hypoglycemic, antiglycation, and antioxidative cytoprotective properties, in order to provide possible evidence for future nutraceutical applications. The α-amylase and α-glucosidase enzyme inhibition, interference with advanced glycation end-products (AGE) formation, and metal chelating abilities were studied. Moreover, the possible antioxidant cytoprotective properties of PGE under hyperglycemic conditions were assayed. Phenolic profile of the extract was characterized by integrated chromatographic and spectrophotometric methods. PGE resulted able to strongly inhibit the tested enzymes, especially α-glucosidase, and exerted chelating and antiglycation properties. Also, it counteracted the intracellular oxidative stress under hyperglycemic conditions, by reducing the levels of reactive oxygen species and total glutathione. Among the identified phenolics, rutin was the most abundant flavonoid (about 4 % w/w). Present results suggest PGE to be a possible remedy for hyperglycemia management and encourage further studies to exploit its promising properties.

Thyroid Peroxidase Activity is Inhibited by Phenolic Compounds-Impact of Interaction

The aim of this study was to estimate the mode of thyroid peroxidase (TPO) inhibition by polyphenols: Chlorogenic acid, rosmarinic acid, quercetin, and rutin. All the tested polyphenols inhibited TPO; the IC50 values ranged from 0.004 mM to 1.44 mM (for rosmarinic acid and rutin, respectively). All these pure phytochemical substances exhibited different modes of TPO inhibition. Rutin and rosmarinic acid showed competitive, quercetin-uncompetitive and chlorogenic acid-noncompetitive inhibition effect on TPO. Homology modeling was used to gain insight into the 3D structure of TPO and molecular docking was applied to study the interactions of the inhibitors with their target at the molecular level. Moreover, the type and strength of mutual interactions between the inhibitors (expressed as the combination index, CI) were analyzed. Slight synergism, antagonism, and moderate antagonism were found in the case of the combined addition of the pure polyphenols. Rutin and quercetin as well as rutin and rosmarinic acid acted additively (CI = 0.096 and 1.06, respectively), while rutin and chlorogenic acid demonstrated slight synergism (CI = 0.88) and rosmarinic acid with quercetin and rosmarinic acid with chlorogenic acid showed moderate antagonism (CI = 1.45 and 1.25, respectively). The mixture of chlorogenic acid and quercetin demonstrated antagonism (CI = 1.79). All the polyphenols showed in vitro antiradical ability against 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid), ABTS. The highest ability (expressed as IC50) was exhibited by rosmarinic acid (0.12 mM) and the lowest value was ascribed to quercetin (0.45 mM).

[Screening for active components of Sophorae Flos on inhibiting AGEs formation based on non-enzymatic glycation reaction]

Sugar-poison caused blood-heat is the pathological basis of many complications of diabetes. Advanced glycation end products( AGEs) are considered as the potential glycotoxic factor that can cause blood-heat. Sophorae Flos hold the effect of removing pathogenic heat from blood. In this study,chromatographic non-enzymatic glycation reaction system of bovine serum albumin( BSA)/methylglyoxal( MGO) and Sophorae Flos was established to identify active components in Sophorae Flos inhibiting AGEs formation. The HPLC was used to analyze chromatograms before and after the incubation of Sophorae Flos and methylglyoxal. Changes of chromatographic peaks of eight compounds was found. It is speculated that this change may be due to new substance produced by the reaction of active components in Sophorae Flos and methylglyoxal,and these active components may be flavonoid component rutin. Further investigation for the effects of rutin and MGO reaction( 1 ∶ 1,1 ∶ 3,3 ∶ 1) for 6 days on the formation of AGEs was performed. The results showed that the inhibition activity of rutin on AGEs production was most obvious when the reaction ratio was 1 ∶3,and the most inhibition was in 24 h and stabilized after 3 d. The product of the reaction of rutin with MGO was identified by LC-ESI-MS/MS,which indicated that the newly formed seven substances were the mono-and di-MGO adducts of rutin. This study showed that rutin is the active component on Sophorae Flos for removing pathogenic heat from blood by forming new compounds to inhibit the formation of sugar poison products,which provides reference for rational application of Sophorae Flos.

A quercetin-based flavanoid (rutin) reverses amyloid fibrillation in β-lactoglobulin at pH 2.0 and 358 K

β-lactoglobulin (BLG) is a well characterized milk protein and a model for folding and aggregation studies. Rutin is a quercetin based-flavanoid and a famous dietary supplement. It is a potential protector from coronary heart disease, cancers, and inflammatory bowel disease. In this study, amyloid fibrillation is reported in BLG at pH 2.0 and temperature 358 K. It is inhibited to some extent by rutin with a rate of 99.3 h^-1 M^-1. Amyloid fibrillation started taking place after 10 h of incubation and completed near 40 h at a rate of 16.6 × 10^-3 h^-1, with a plateau during 40-108 h. Disruption of tertiary structure of BLG and increased solvent accessibility of hydrophobic core seem to trigger intermolecular assembly. Increase in 7% β-sheet structure at the cost of 10% α-helical structures and the electron micrograph of BLG fibrils at 108 h further support the formation of amyloid. Although it could not block amyloidosis completely, and even the time required to reach plateau remains the same, a decrease of growth rate from 16.6 × 10^-3 to 13.5 × 10^-3 h^-1 was observed in the presence of 30.0 μM rutin. Rutin seems to block solvent accessibility of the hydrophobic core of BLG. A decrease in the fibril population was observed in electron micrographs, with the increase in rutin concentration. All evidences indicate reversal of fibrillation in BLG in the presence of rutin.

In Vitro Pollen Tube Growth Reveals the Cytotoxic Potential of the Flavonols, Quercetin and Rutin

Flavonols are phytochemicals widely found in commonly consumed foods. In spite of their beneficial effects on human health, however, cytotoxicity and even suspected genotoxicity have also been reported for the flavonol, quercetin. This points to the need for preventive studies to identify any cytotoxic effects associated with pure flavonol intake. This work was performed with the aim of verifying whether a plant-based in vitro system, the pollen tube, could be used to evaluate the cytotoxic potential of exogenous flavonols. Increasing concentrations of the aglycone, quercetin, and its glycoside, rutin, were assayed with regard to tube growth of kiwifruit pollen, determined by applying the pollen tube growth test protocol. This test, based on the photometric quantification of pollen tube mass production in suspension cultures, has already been applied in the sensitive and reliable toxicological evaluation of a wide range of chemicals. Whereas 60-800 microM rutin promoted kiwifruit pollen tube elongation, 10-50 microM quercetin strongly inhibited growth, and also produced irreversible malformations, such as screw-like tube growth, abnormal vacuolation, alteration of organelle streaming, and nuclear positioning. Thus, the cytotoxic potentials of the two flavonols have been confirmed to differ. Pollen tubes seem to afford a promising test system for a preventive, rapid in vitro biosafety assessment of antioxidant nutritional supplements, without using laboratory animals.

Bioproduction of Quercetin and Rutinose Catalyzed by Rutinosidase: Novel Concept of "Solid State Biocatalysis"

Quercetin is a flavonoid largely employed as a phytochemical remedy and a food or dietary supplement. We present here a novel biocatalytic methodology for the preparation of quercetin from plant-derived rutin, with both substrate and product being in mostly an undissolved state during biotransformation. This "solid-state" enzymatic conversion uses a crude enzyme preparation of recombinant rutinosidase from Aspergillus niger yielding quercetin, which precipitates from virtually insoluble rutin. The process is easily scalable and exhibits an extremely high space-time yield. The procedure has been shown to be robust and was successfully tested with rutin concentrations of up to 300 g/L (ca 0.5 M) at various scales. Using this procedure, pure quercetin is easily obtained by mere filtration of the reaction mixture, followed by washing and drying of the filter cake. Neither co-solvents nor toxic chemicals are used, thus the process can be considered environmentally friendly and the product of "bio-quality." Moreover, rare disaccharide rutinose is obtained from the filtrate at a preparatory scale as a valuable side product. These results demonstrate for the first time the efficiency of the "Solid-State-Catalysis" concept, which is applicable virtually for any biotransformation involving substrates and products of low water solubility.

Sodium rutin ameliorates Alzheimer's disease-like pathology by enhancing microglial amyloid-β clearance

The accumulation of aggregated amyloid-β (Aβ) in the brain is the first critical step in the pathogenesis of Alzheimer's disease (AD), which also includes synaptic impairment, neuroinflammation, neuronal loss, and eventual cognitive defects. Emerging evidence suggests that impairment of Aβ phagocytosis and clearance is a common phenotype in late-onset AD. Rutin (quercetin-3-rutinoside) has long been investigated as a natural flavonoid with different biological functions in some pathological circumstances. Sodium rutin (NaR), could promote Aβ clearance by increasing microglial by increasing the expression levels of phagocytosis-related receptors in microglia. Moreover, NaR promotes a metabolic switch from anaerobic glycolysis to mitochondrial OXPHOS (oxidative phosphorylation), which could provide microglia with sufficient energy (ATP) for Aβ clearance. Thus, NaR administration could attenuate neuroinflammation and enhance mitochondrial OXPHOS and microglia-mediated Aβ clearance, ameliorating synaptic plasticity impairment and eventually reversing spatial learning and memory deficits. Our findings suggest that NaR is a potential therapeutic agent for AD.

Complex Structures of Monoglucosylrutin with ent-Gallocatechin-3- O-gallate and Epigallocatechin-3- O-gallate in Aqueous Solutions and the Mechanism of Color Change Induced by Complexation

The addition of ent-gallocatechin-3- O-gallate ( ent-GCg) or epigallocatechin-3- O-gallate (EGCg) to an aqueous solution of 4^G-α-glucopyranosylrutin (monoglucosylrutin, MGR) causes the color of the solution to weaken due to complexation between MGR and these flavan-3-ols. Copigmentation is a well-known color change phenomenon resulting from the complexation of flavonoids that deepens and strengthens the color of the solution, whereas MGR/catechin complexation results in the opposite change in color (i.e., weakening). In order to gain insight into the mechanism underlying the rare changes in the color of solutions of complexes between flavonoids, the structures of the MGR monomer and the complexes in aqueous solutions and their photochemical properties were investigated by computational methods. Molecular dynamics simulations and subsequent density functional theory (DFT) calculations revealed that the complex structures are stabilized through aromatic/aromatic, CH/π, and OH/O interactions as direct intermolecular forces and that many solvent water networks would contribute to the complexations. Time-dependent DFT calculations showed that the change in the color of an MGR/ ent-GCg solution is due only to a decrease in absorbance, whereas that of an MGR/EGCg solution is due to both a decrease in absorbance and a hypsochromic shift.

Utilization of Microfluidics for the Preparation of Polymeric Nanoparticles for the Antioxidant Rutin: A Comparison with Bulk Production

OBJECTIVE

To compare the characteristics of rutin-loaded PLGA (poly(lactic-coglycolic acid)) nanoparticles prepared using a single emulsion evaporation method (bulk method) and a nanoprecipitation method using microfluidics.

METHODS

Rutin-loaded PLGA nanoparticles were produced using different methods and characterized for size, zeta potential, entrapment efficiency (EE) and drug loading (DL). A design of experiments approach was used to identify the effect of method parameters to optimize the formulation. DSC was used to investigate the solid-state characteristics of rutin and PLGA and identify any interactions in the rutin-loaded PLGA nanoparticles. The release of rutin from PLGA nanoparticles was examined in biorelevant media and phosphate buffer (PBS).

RESULTS

The optimal formulation of rutin-loaded PLGA nanoparticles produced using a microfluidics method resulted in a higher entrapment efficiency of 34 ± 2% and a smaller size of 123 ± 4 nm compared to a bulk method (EE 27 ± 1%, size 179 ± 13 nm). The solidstate of rutin and PLGA changed from crystalline to amorphous with the preparation of rutin- loaded PLGA nanoparticles. More importantly, using microfluidics, rutin released faster from rutin-loaded PLGA nanoparticles in biorelevant media and PBS with higher burst release compared to the rutin release from the nanoparticles prepared by using the bulk method.

CONCLUSION

Rutin can be encapsulated in nanoparticles formulated with different methods with mean sizes of less than 200 nm. Microfluidics produced more uniform rutin-loaded PLGA nanoparticles with a higher EE, DL and faster release compared to a bulk production method.

Anti-angiogenic Activity of Major Phenolics in Tamarind Assessed with Molecular Docking Study on VEGF Kinase Proteins

BACKGROUND AND OBJECTIVE

The waste products of the tamarind canning industry have been discarded; however, it has potential health benefits. Herein, the study was carried out HPLC profiling of phenolic constituents of Tamarindis indica pericarp and seeds. Furthermore, the cytotoxic activity against HUH-7 cells was evaluated and assessed with molecular docking study on angiogenesis-related VEGF kinase proteins in addition to evaluating the level of released VEGF in treated HUH-7 cells by ELISA.

MATERIALS AND METHODS

Folin-ciocalteu and AlCl3 assays were used for quantification of total phenolics (TPC) and total flavonoids (TFC) contents, respectively. Molecular docking study was done on VEGF kinase proteins.

RESULTS

TPC and TFC of pericarp and seeds were 0.35±0.02 g GAE g-1 DE and 0.12±0.009 g CE g-1 DE, 0.39±0.01 g GAE g-1 DE and 0.03±0.006 g CE g-1 DE, respectively. In pericarp, 8 phenolics were tentatively identified, where (+)-catechin was the major (27,386.04 μg g-1 DE) followed by gallic acid and naringenin (931.47, 500.42 μg g-1 DE) respectively. While in seeds, 11 phenolics were tentatively identified, where naringenin was the major (95,305.47 μg g-1 DE) followed by (+)-catechin and rutin (54,930.29, 15,361.66 μg g-1 DE) respectively. Aqueous and methanol seeds extracts exhibit cytotoxic effect with IC50 27.4±1.81 and 13.4±0.94 μg mL-1, respectively, it was more potent than aqueous and methanol pericarp extracts which had IC50 132±5.82 and 61.6±3.16 μg mL-1. The tested phenolics were fit on the active sites of VEGF kinase targets with varied degree of interactions. The cytotoxic and anti-angiogenic activities were confirmed in light of phenolics docking interactions.

CONCLUSION

Results demonstrate for the first time that phenolics could inhibit angiogenesis via inhibiting kinase proteins, which could therefore be developed as antiangiogenic drugs.

Cold Plasma as an Innovative Construction Method of Voltammetric Biosensor Based on Laccase

Development of new, faster methods of biosensor construction is a huge challenge for current science and industry. In this work, biosensor construction was carried out using a new soft plasma polymerization (SPP) method in which a bio-recognition layer of laccase enzyme was polymerized and bonded to a glassy carbon electrode (GCE) substrate under atmospheric pressure with a corona discharge jet. Laccase belongs to the oxidoreductase enzyme group with four copper atoms in its active center. Application of the corona SPP plasma method allows reduction of the time needed for biosensor construction from several hours to minutes. The presented work includes optimization of the laccase bio-recognition layer deposition time, structural studies of the deposited laccase layer, as well as study of the fabricated biosensor applicability for the determination of Rutin in real pharmaceutical samples. This method produces a biosensor with two linear ranges from 0.3 μmol/dm³ to 0.5 μmol/dm³ and from 0.8 μmol/dm³ to 16 μmol/dm³ of Rutin concentration. Results shown in this work indicate that application of the one-step, corona SPP method enables biosensor construction with comparable analytical parameters to biosensors fabricated by conventional, multi-step, wet methods.

Pulsed Electric Fields-Modified Ferritin Realizes Loading of Rutin by a Moderate pH Transition

Ferritin shares a conserved 24-subunit spherical structure and a unique reversible self-assembly characteristic. In the present work, pulsed electric fields (PEF) technology was used to treat red bean seed ferritin deprived of iron (apoRBF) to fabricate a PEF-modified apoRBF (PEFF). Results indicated that PEF treatment at 20 kV/cm for 7.05 ms retained the spherical structure but decreased the α-helix/β-sheet contents of ferritin. Differential scanning calorimetry (DSC) and UV-vis analyses proved that the thermal stability of the PEFF was decreased. Consequently, PEFF disassembled at pH 3.6 and reassembled when the pH was restored to 7.0, exhibiting a more moderate condition relevant to the traditional approach. Using the pH 3.6/7.0 transition routine, rutin molecules were successfully loaded within PEFF nanoparticle. The rutin-loaded PEFF showed a diameter of 12 nm with an encapsulation ratio of 13.7% (w/w). Moreover, PEFF played a role in protecting the encapsulated rutin molecules upon thermal treatment (20-70 °C). This work will be beneficial for extension of PEF application in protein modification and will improve ferritin functionalization as a carrier for food bioactive molecules by a moderate pH transition method.