120 research outputs found

    Biodegradable and biocompatible spherical dendrimer nanoparticles with a gallic acid shell and a double-acting strong antioxidant activity as potential device to fight diseases from \uaboxidative stress\ubb

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    Gallic acid (GA) is a natural polyphenol with remarkable antioxidant power present in several vegetables and fruits. A normal feeding regime leads to a daily intake of GA which is reasonably regarded as \u2018\u2018natural\u2019\u2019 and \u2018\u2018safe\u2019\u2019 for humans. It owns strong potentials as alternative to traditional drugs to treat several diseases triggered by oxidative stress (OS), but poor gastrointestinal absorbability, pharmacokinetic drawbacks and fast metabolism limit its clinical application. In this work, a fifth generation polyester-based dendrimer was firstly prepared as a better absorbable carrier to protect and deliver GA. Then, by its peripheral esterification with GA units, a GA-enriched delivering system (GAD) with remarkable antioxidant power and high potential against diseases from OS, was achieved. Scanning Electron Microscopy results and Dynamic Light Scattering analysis, revealed particles with an average size around 387 and 375 nm respectively and an extraordinarily spherical morphology. These properties, by determining a large particles surface area, typically favor higher systemic residence time and bio-efficiency. Z-potential of -25 mV suggests satisfactory stability in solution with tendency to form megamers and low PDI. GAD showed intrinsic antioxidant power, higher than GA by 4 times and like prodrugs, it can carry contemporary several bioactive GA units versus cells. In physiological condition, the action of Pig Liver Esterase (PLE), selected as a model of cells esterase, hydrolyzes GAD to non-cytotoxic small molecules, thus setting free the bioactive GA units, for further antioxidant effects. Cytotoxicity studies performed on two cell lines demonstrated a high cell viability

    By connecting a synthetic scaffold and a natural shell of Gallic acid: an innovative double-acting antioxidant device to figh \uaboxidative stress\ubb.

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    Oxidative stress (OS) is involved in the onset and developing of most degenerative diseases hard to fight with exsisting synthetic drugs without adverse side effects. Gallic acid (GA) (Figure 1), a natural triphenolic acid present in several plants, fruits and common foodstuffs, is provided both with the basic nutritional values and with several extra health benefits such as a remarkable antioxidant power. GA exhibited abilities in protecting cells from OS via a number of pathways without triggering unpleasant side effects.1 GA several potentials could be exploited both in industry and in medicine but unfortunately its clinical application is limited by its pharmacokinetic drawbacks, poor bioavailability, slow GIT absorption, fast metabolism and short half-life. Dendrimer nanoparticles, thanks to their nonpareil physicochemical properties are extensively exploited in nanomedicine to control molecular weight, hydrophilicity, solubility,2-4 bioavailability and pharmacokinetic behaviour of drugs as well as to protect them from early degradation or fast metabolism. With the aim at minimizing GA's limitations for medical purposes, in this study, a G5 polyester-based dendrimer was prepared and subsequently, it was peripherally further esterified with bioactive GA

    A Preliminary Color Study of Different Basil-Based Semi-Finished Products during Their Storage

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    open6: Basil-based semi-finished products, which are mainly used as an intermediate to produce the typical pesto sauce, are prepared and exported all over the world. Color is a fundamental organoleptic requirement for the acceptability of these semi-finished products by the manufacturers of the pesto sauce. Some alternative formulations, which adjust the typical industrial recipe by both changing the preservative agent (ascorbic acid, citric acid, or a mixture of both) and introducing a preliminary thermic treatment (blast chilling), were evaluated. In this work, a fast and non-destructive spectrophotometric analysis, to monitor the color variations in these food products during their shelf-life, was proposed. The raw diffuse reflectance spectra (380–900 nm) obtained by a UV–visible spectrophotometer, endowed with an integrating sphere, together with the CIELab parameters (L*, a*, b*) automatically obtained from these, were considered, and elaborated using multivariate statistical analysis (principal component analysis). From this preliminary study, blast chilling, together with the use of ascorbic acid, proved to be the best solution to better preserve the color of these products during their shelf-life.openTurrini, Federica; Farinini, Emanuele; Leardi, Riccardo; Grasso, Federica; Orlandi, Valentina; Boggia, Raffaella;Turrini, Federica; Farinini, Emanuele; Leardi, Riccardo; Grasso, Federica; Orlandi, Valentina; Boggia, Raffaell

    Traditional decoction and PUAE aqueous extracts of pomegranate peels as potential low-cost anti-tyrosinase ingredients

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    open6The aim of the study is to evaluate the anti-tyrosinase activity of dierent aqueous extracts obtained from pomegranate juice processing by-products. External pomegranate peels of two certified cultivars (Akko and Wonderful), were extracted using only water as the extraction solvent. A traditional decoction and a pulsed ultrasound-assisted extraction (PUAE), both 10 min long, were performed and compared. All the aqueous extracts proved to be rich in bioactive compounds. In particular, the total phenolic content (TPC) ranged from 148 to 237 mg gallic acid equivalent (GAE)/g of dried peels (DW), the radical-scavenging ability (RSA) ranged from 307 to 472 mg ascorbic acid equivalent (AAE)/g DW, the free ellagic acid content (EA) ranged from 49 to 94 g/mL, and the ellagitannins (ETs) ranged from 242 to 340 g/mL. For both cultivars, PUAE extracts had higher ET content and a lower EC50, while the decoctions had slightly higher TPC, RSA, and free EA amounts. Principal component analysis (PCA) highlighted the direct correlation between the ET content and the tyrosinase enzyme inhibition (lower values of EC50). These findings suggest the potential use of both these natural extracts as low-cost lightening and/or anti-browning ingredients exploitable in several formulations (e.g., cosmetics) or extemporarily usable.openFEDERICA TURRINI; PAOLA MALASPINA; PAOLO GIORDANI; SILVIA CATENA; PAOLA ZUNIN; RAFFAELLA BOGGIA;Turrini, Federica; Malaspina, Paola; Giordani, Paolo; Catena, Silvia; Zunin, Paola; Boggia, Raffaell

    Formulation Strategies to Improve Oral Bioavailability of Ellagic Acid

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    Ellagic acid, a polyphenolic compound present in fruit and berries, has recently been the object of extensive research for its antioxidant activity, which might be useful for the prevention and treatment of cancer, cardiovascular pathologies, and neurodegenerative disorders. Its protective role justifies numerous attempts to include it in functional food preparations and in dietary supplements, and not only to limit the unpleasant collateral effects of chemotherapy. However, ellagic acid use as a chemopreventive agent has been debated because of its poor bioavailability associated with low solubility, limited permeability, first pass effect, and interindividual variability in gut microbial transformations. To overcome these drawbacks, various strategies for oral administration including solid dispersions, micro and nanoparticles, inclusion complexes, self-emulsifying systems, and polymorphs were proposed. Here, we listed an updated description of pursued micro and nanotechnological approaches focusing on the fabrication processes and the features of the obtained products, as well as on the positive results yielded by in vitro and in vivo studies in comparison to the raw material. The micro and nanosized formulations here described might be exploited for pharmaceutical delivery of this active, as well as for the production of nutritional supplements or for the enrichment of novel foods

    In Silico and In Vitro Study of Antioxidant Potential of Urolithins

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    In this work, quantum chemical calculations based on density functional theory (DFT) were performed to predict the antioxidant potential of four bioactive gut microbiota metabolites of the natural polyphenols ellagitannins (ETs) and ellagic acid (EA), also known as urolithins (UROs). In order to evaluate their ability to counter the effect of oxidative stress caused by reactive oxygen species (ROS), such as the hydroperoxyl radical (•OOH), different reaction mechanisms were investigated, considering water and lipid-like environments. Through our in silico results, it emerged that at physiological pH, the scavenging activity of all urolithins, except urolithin B, are higher than that of trolox and other potent antioxidants existing in nature, such as EA, α-mangostin, allicin, caffeine and melatonin. These findings were confirmed by experimental assays

    Non-PAMAM amino acids-modified dendrimers nanoparticles for enhancing water-solubility of insoluble bioactive molecules: our state of the art

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    Non-PAMAM amino acids-modified dendrimers nanoparticles for enhancing water-solubility of insoluble bioactive molecules: our state of the art Silvana Alfei,* Andrea Spallarossa, Silvia Catena, Federica Turrini, Guendalina Zuccari, Anna Pittaluga, Raffaella Boggia Dipartimento di Farmacia, Universit\ue0 di Genova, Viale Cembrano 4, I-16148 Genova, Italy E-mail: [email protected] ABSTRACT Water-solubility is essential for GIT absorbability or parenteral administration of drugs, therefore it is a key parameter to achieve the systemic drug concentration necessary for an effective therapeutic activity. Unfortunately, low aqueous solubility is the major problem with bioactive chemical entities (BCEs), in fact, more than 40% BCEs developed in pharmaceutical industry are practically water-insoluble. As a consequence, great are the research efforts focused on the development of new techniques aiming at enhancing it. Toxic excipients and harmful solubilizing agents were also extensively used for solubilizing and delivering non water-soluble drugs, despite the resulting unpleasant side effects complained of by patients. Nowadays, safer strategies, such as drugs physicochemical modifications or particle size reduction, crystal engineering, salt formation, solid dispersion, use of surfactant and complexation are being exploited. As far as what regards dispersion/complexation techniques, nanoparticles, including dendrimers, are intensely utilized for this purpose, thus in parallel achieving drugs protection from early degradation, more efficient target delivery into cells and tissues and lower systemic toxicity. Synthetic thiocarbamate (O-TC 1) (Fig. 1) is a non-nucleoside HIV-1 reverse transcriptase inhibitor [1] while Ellagic Acid (EA 2) (Fig. 2) is a polyphenol present in some fruits, nuts and seeds endowed with strong antioxidant, anti-inflammatory and other several healthy properties. Unfortunately, both of them are practically insoluble (Table 1), non orally bioavailable, non parenteral administrable, then non usable for therapeutic purposes in their free forms. Fig. 1: Structure of O-TC 1 Fig. 2: Structure of EA 2 Fig. 3: Examples of hydrophilic (left) and amphiphilic (right) dendrimers structure During the last year, these problems have been addressed and successfully resolved by us, and in this communication, the reached promising outcomes have been summarized and the current state of the art provided. Afar from commercially high cytotoxic PAMAM, five non cells-damaging amino acid-modified hydrophilic (3, 4) [2] and amphiphilic (5-7) [3] dendrimers (Fig. 3) have been synthetized and then used as polymer nano-containers to improve 1 and 2 water-solubility. Five (8-12) [4] and two (13, 14) [5] structurally different drugs-loaded nanodispersions (DPXs) were obtained respectively. The structures were confirmed by FT-IR and NMR analysis and all the samples have resulted in being endowed with very good Drug Loading (DL %). Compound 1, totally insoluble except for in highly diluted DMSO when free, once entrapped in dendrimers, shown to be well soluble both in water and in ethanol. In the case of 2, water-solubility was increased even up to 1000 times compared to the free form. For the prerogatives demonstrated in the performed routine analyses, the prepared DPXs could be considered eligible for biomedical and therapeutic applications thus allowing to exploit 1 and 2 pharmacological properties. REFERENCES: 1. A. Spallarossa et al., Eur. J. Med. Chem., 44, 2190 (2009). 2. S. Alfei & S. Catena, Polym. Advan. Technol., 29, 2735 (2018). 3. S. Alfei & S. Catena, Polym. Int., 67, 1572 (2018). 3. S. Alfei et al., Eur. J. Pharm. Sci., 124, 153 (2018). 4. S. Alfei et al., New J. Chem., 2019, DOI: 10.1039/c8nj05657a

    Characterization data of water-soluble hydrophilic and amphiphilic dendrimers prodrugs for delivering bioactive chemical entities otherwise non soluble.

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    More than 40% of bioactive chemical entities (BCEs) developed in pharmaceutical industry are almost water-insoluble, poorly orally bioavailable and/or not via parenteral administrable, and this strongly limits their clinical applications. Drug Delivery (DD) is an engineered technology dealing with the development of delivery systems (DDSs) able to solubilize, transport, target release and maintain therapeutic drugs concentration where needed for long periods. DD frequently makes use of nanosized carriers, often positive charged, including dendrimer such as commercially available and strongly cationic PAMAM and PEI. Nowadays, uncharged dendrimer scaffolds modified with amino acids-modified in their cationic form, are preferred because a more controlled number of nitrogen atoms causes less damage to cells. Then, two hydrophilic (1, 2) [1] (Fig. 1) and three amphiphilic (3-5) [2] (Fig. 2) water-soluble dendrimers were prepared and completely characterized. Once established through proper routine investigations, that these materials could work well as DDSs, they have been used to physically entrap two completely insoluble BCEs i.e. the thiocarbamate (O-TC) 6 [3] and Ellagic Acid (EA) 7 (Fig. 3) with the aim at improving their solubility and in parallel at protecting them from early degradation, at promoting their fast cellular up-take and thus reducing eventual systemic toxicity. Without resorting to toxic excipients and harmful solubilizing agents often used despite the resulting unpleasant side effects, five structurally different nanodispersions (DPXs) loaded with 6 [4] and two with 7 [5] were achieved and completely characterized to confirm their structure and to evaluate their potentiality in biomedical applications

    Microdispersions of ellagic acid and pomegranate extracts as new potential nutraceutical ingredients

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    The health properties attributed to several fruits (i.e. pomegranates, raspberries, strawberries, blackberry, chestnuts, walnuts, pecan), herbs (tea) and seeds (berries seeds) are attributed to an important group of natural polyphenols classified as hydrolysable tannins (HT) named Ellagitannins (ETs), that have shown in vitro multi-target biological properties relevant to the treatment of several human diseases. In vivo, ETs are rather not absorbed, and they are hydrolysed providing mainly Ellagic acid (EA). EA is endowed with the same biological properties of ETs and it could be considered as the responsible of their health benefits. Unfortunately, EA cannot be exploited for in vivo applications because of its poor water solubility (9.7 \u3bcg/mL) and accordingly low bioavailability. At first, aiming to increase EA solubility, an EA solid microdispersion (EA-md) was realized by employing only water and low methoxylated pectin, as a food compatible excipient, by applying spray drying technology. EA-md showed a 22% (w/w) Drug Loading (DL), a 30 times improved water solubility maintaining a remarkable radical scavenging activity [1]. It has been analytically characterised and used for in vivo pharmacological treatments in order to evaluate it as potential nutraceutical ingredient. Adult (3-6 months old) and old (20-22 old months) male mice were chronically administered EA-md dissolved in the drinking water (about 150 mg / Kg) for 14 days. During this period, animals were monitored for the spontaneous motor activity and for curiosity before, during and at the end of the EA-md treatment. Adult and old mice were then sacrificed for \u201cex vivo, in vitro\u201d analysis to test the efficiency of noradrenaline release from cortical nerve endings. It is known that noradrenaline exocytosis from cortical nerve endings is significantly impaired during ageing. We found that the chronic administration of EA-md did not alter the noradrenaline exocytosis from cortical nerve endings of adult mice, but significantly recovered the reduced noradrenaline overflow in aged mice. Further investigations are needed to explore the cellular cascade of events accounting for the beneficial effect. In a second step, pomegranate, as a natural source of EA, has been considered to similarly prepare and investigate an analogous formulation. Since pomegranate fruit is recognized as one of the most important sources of ETs, mainly localized in the by-products obtained after industrial juice squeezing, a method to convert the squeezing marcs into a potential nutraceutical ingredient has been explored. In particular, Pulsed Ultrasound-Assisted Extraction (PUAE), using just water as solvent, resulted to be suitable for extracting the water-soluble bioactive molecules (PEx), whose content in hydrolysable tannins, standardized in EA, has been determined. Furthermore, the already mentioned spray drying microdispersion has been employed to formulate and to stabilize it over time. This last formulation (PEx-md) will be subjected to the already mentioned pharmacological experiments in order to study its nutraceutical properties too. [1] S. Alfei, F. Turrini, S. Catena, P. Zunin, B. Parodi, G. Zuccari, A.M. Pittaluga, R. Boggia, New J. Chem, 43, 2438-2448 DOI: 10.1039/C8NJ05657

    Combining excitation-emission matrix fluorescence spectroscopy, parallel factor analysis, cyclodextrin-modified micellar electrokinetic chromatography and partial least squares class-modelling for green tea characterization

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    In this study, an alternative analytical approach for analyzing and characterizing green tea (GT) samples is proposed, based on the combination of excitation–emission matrix (EEM) fluorescence spectroscopy and multivariate chemometric techniques. The three-dimensional spectra of 63 GT samples were recorded using a Perkin–Elmer LS55 luminescence spectrometer; emission spectra were recorded between 295 and 800 nm at excitation wavelength ranging from 200 to 290 nm, with excitation and emission slits both set at 10 nm. The excitation and emission profiles of two factors were obtained using Parallel Factor Analysis (PARAFAC) as a 3-way decomposition method. In this way, for the first time, the spectra of two main fluorophores in green teas have been found. Moreover, a cyclodextrin-modified micellar electrokinetic chromatography method was employed to quantify the most represented catechins and methylxanthines in a subset of 24 GT samples in order to obtain complementary information on the geographical origin of tea. The discrimination ability between the two types of tea has been shown by a Partial Least Squares Class-Modelling performed on the electrokinetic chromatography data, being the sensitivity and specificity of the class model built for the Japanese GT samples 98.70% and 98.68%, respectively. This comprehensive work demonstrates the capability of the combination of EEM fluorescence spectroscopy and PARAFAC model for characterizing, differentiating and analyzing GT samples
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