Development of an Enriched Polyphenol (Natural Antioxidant) Extract from Orange Juice (Citrus sinensis) by Adsorption on Macroporous Resins

Orange (Citrus sinensis) juice contains a high amount of antioxidant compounds, such as polyphenols and vitamins. The aim of this work was to develop an adsorption procedure for the quantitative recovery of polyphenols from fresh orange juice. Different macroporous resins have been selected to evaluate their affinity for phenolic compound in order to purify the antioxidant compounds from the orange juice. The main compounds of orange juice were firstly characterized using an UPLC-UV-HRMS to define the metabolite profile, and subsequently three different types of adsorbent (XAD-2, XAD-4, and XAD-16N) were tested to concentrate these bioactive compounds. The time of contact was selected based on kinetic studies, and subsequently the adsorption and elution conditions were optimized in order to maximize the recovery of phenolic compounds to obtain an extract rich of bioactive compounds. Lastly, antioxidant capacity of the orange juice extract of selected macroporous resin, obtained under optimized conditions, was determined by in vitro antioxidant assays

A new cineol derivative, polyphenols and norterpenoids from Saharan myrtle tea (Myrtus nivellei): Isolation, structure determination, quantitative determination and antioxidant activity

Abstract The phytochemical profile of decoction and infusion, obtained from the dried leaves of M. nivellei, consumed as tea in Saharan region, was characterized by UHPLC-PDA-HRMS. Fourteen compounds were characterized and, to confirm the proposed structures a preparative procedure followed by NMR spectroscopy was applied. Compound 3 (2-hydroxy-1,8-cineole disaccharide) was a never reported whereas a bycyclic monoterpenoid glucoside (2), two ionol glucosides (1 and 12), a tri-galloylquinic acid (4), two flavonol glycosides (5 and 9), and a tetra-galloylglucose (7), were reported in Myrtus spp. for the first time. Five flavonol O-glycosides (6, 8, 10–11, and 14) togheter a flavonol (13) were also identified. Quantitative determination of phenolic constituents from decoction and infusion has been performed by HPLC-UV-PDA. The phenolic content was found to be 150.5 and 102.6 mg/g in decoction and infusion corresponding to 73.8 and 23.6 mg/100 mL of a single tea cup, respectively. Myricetin 3-O-β-d-(6″-galloyl)glucopyranoside (5), isomyricitrin (6) and myricitrin (8) were the compounds present in the highest concentration. The free-radical scavenging activities of teas and isolated compounds was measured by the DPPH assay and compared with the values of other commonly used herbal teas (green and black teas). Decoction displayed higher potency in scavenging free-radicals than the infusion and green and black teas

Development of analytical methodology for determination of emerging contaminants in enviroment and food

2012 - 2013In recent years, fate, occurrence and potential adverse effect of emerging contaminants (ECs) in the environment have received an increased attention by scientific community. The ECs are a broad category of chemicals, mainly organic compounds, that are not currently covered by existing regulations but they may be candidates for future regulation, as they may be potential threats to human health and environmental safety. The ECs are mainly substances of anthropogenic origin, introduced continuously into the environment in large quantities and distributed ubiquitously in the ecosystem, due to their wide consumption. Recent studies have indicated that most of them are environmentally persistent, bioactive, and certain have a high potential for bioaccumulation. In literature data are still too few regarding their toxicity, distribution and fate and consequently, it is not still possible to assess their real impact on the environment and on human health. For these reasons it is important to design analytical procedures for monitoring specific environmental compartments and to provide the basis for drawing conclusions about the occurrence, the persistence and hazard of ECs in the environment. Currently, the main objectives of the research and monitoring of ECs are the development of accurate and sensitive analytical methods able to simultaneously analyze multiple chemical classes of ECs in different environmental compartments with different complexity. In line with these requirements, in this PhD project, three multi-residue methods were developed for the determination of three different classes of ECs in different and complex environmental matrices... [edited by Author]XII n.s

Application of dispersive liquid–liquid microextraction for the determination of aflatoxins B1, B2, G1 and G2 in cereal products

The application of dispersive liquid-liquid microextraction (DLLME) technique for the rapid analysis of aflatoxins B(1), B(2), G(1) and G(2) in maize, rice and wheat products has been evaluated. After extraction of aflatoxins from cereal matrices with a mixture of methanol/water 8:2 (v/v), the analytes were rapidly transferred from the extract to another small volume of organic solvent, chloroform, by DLLME. Aflatoxins were determined using high performance liquid chromatography with florescence detection and photochemical post-column derivatization. Parameters affecting both extraction and DLLME procedures, such as extraction solvent, type and volume of DLLME extractant, volume of water and salt effect, were systematically investigated and optimized to achieve the best extraction efficiency. Under the optimal experimental conditions, the whole analytical method provides enrichment factors around 2.5 times and detection limits (0.01-0.17 mu g kg(-1)) below the maximum levels imposed by current regulation for aflatoxins in cereals and cereal products intended for direct human consumption. Recoveries (67-92%) and repeatability (RSD < 10, n = 3), tested in three different cereal matrices, meet the performance criteria required by EC Regulation No. 401/2006 for the determination of the levels of mycotoxins in foodstuffs. The proposed method was successfully applied to the analysis of retail cereal products with quantitative results comparable to the immunoaffinity chromatography (IAC). The main advantages of developed method are the simplicity of operation, the rapidity to achieve a very high sample throughput and low cost

Ultra-preconcentration and determination of selected pharmaceutical and personal care products in different water matrices by solid-phase extraction combined with dispersive liquid–liquid microextraction prior to ultra high pressure liquid chromatography tandem mass spectrometry analysis

Pharmaceutical and personal care products (PPCPs) are one of the most important classes of emerging contaminants. The potential of ecological and environmental impacts associated with PPCPs are of particular concern because they continually penetrate the aquatic environment. This work describes a novel ultra-preconcentration technique for the rapid and highly sensitive analysis of selected PPCPs in environmental water matrices at ppt levels. Selected PPCPs were rapidly extracted and concentrated from large volumes of aqueous solutions (500 and 250 mL) by solid-phase extraction combined with dispersive liquid–liquid microextraction (SPE–DLLME) and then analyzed using UHPLC–MS/MS. Experimental parameters were carefully investigated and optimized to achieve the best SPE–DLLME efficiency and higher enrichment factors. The best results were obtained using the ternary mixture acetonitrile/methanol/dichloromethane 3:3:4, v/v/v, both as SPE eluent and DLLME extractant/dispersive mixture. DLLME aqueous solution (5% NaCl, 10 mg L−1 TBAB) was also modified to improve the extraction efficiency of more hydrophilic PPCPs. Under the optimal conditions, an exhaustive extraction for most of the investigated analytes (recoveries >70%), with a precision (RSD <10%) and very high enrichment factors were attained for different aqueous matrices (drinking, sea, river and wastewater). Method detection and quantification limits were at very low ppt levels and below 1 and 3 ng L−1, respectively, for 15 of selected PPCPs. The proposed analytical procedure offers numerous advantages such as the simplicity of operation, rapidity, a high enrichment factor and sensitivity. So it is suitable for monitoring and studies of occurrence of PPCPs in different environmental compartments

pH-Controlled dispersive liquid-liquid microextraction for the analysis of ionizable compounds in complex matrices: Case study of ochratoxin A in cereals

A new sample preparation procedure, termed pH-controlled dispersive liquid–liquid microextraction (pH-DLLME), has been developed for the analysis of ionisable compounds in highly complex matrices. This DLLME mode, intended to improve the selectivity and to expand the application range of DLLME, is based on two successive DLLMEs conducted at opposite pH values. pH-DLLME was applied to determination of ochratoxin A (OTA) in cereals. The hydrophobic matrix interferences in the raw methanol extract (disperser, 1 mL) were removed by a first DLLME (I DLLME) performed at pH 8 to reduce the solubility of OTA in the extractant (CCl4, 400 L). The pH of the aqueous phase was then adjusted to 2, and the analyte was extracted and concentrated by a second DLLME (extractant, 150 L C2H4Br2). The main factors influencing the efficiency of pH-DLLME including type and volume of I DLLME extractant, as well as the parameters affecting the OTA extraction by II DLLME, were studied in detail. Under optimum conditions, the method has detection and quantification limits of 0.019 and 0.062 g kg−1, respectively, with OTA recoveries in the range of 81.2–90.1% (n = 3). The accuracy of the analytical procedure, evaluated with a reference material (cereal naturally contaminated with OTA), is acceptable (accuracy of 85.6% ± 1.7, n = 5). The applicability of pH-DLLME to the selective extraction of other ionisable compounds, such as acidic and basic pharmaceutical products was also demonstrated. The additional advantages of pH-DLLME are a higher selectivity and the extension of this microextraction technique to highly complex matrices

An Overview on Citrus aurantium L.: Its Functions as Food Ingredient and Therapeutic Agent.

Citrus aurantium L. (Rutaceae), commonly known as bitter orange, possesses multiple therapeutic potentials. These biological credentials include anticancer, antianxiety, antiobesity, antibacterial, antioxidant, pesticidal, and antidiabetic activities. The essential oil of C. aurantium was reported to display marked pharmacological effects and great variation in chemical composition depending on growing locations but mostly contained limonene, linalool, and β-myrcene. Phytochemically, C. aurantium is rich in p-synephrine, an alkaloid, and many health-giving secondary metabolites such as flavonoids. Animal studies have demonstrated a low affinity of p-synephrine for adrenergic receptors and an even lower affinity in human models. The present review focuses on the different biological activities of the C. aurantium in animal and human models in the form of extract and its pure secondary metabolites. Finally, it is concluded that both the extract and isolated compounds have no unwanted effects in human at therapeutic doses and, therefore, can confidently be used in various dietary formulations

Critical analysis of green extraction techniques used for botanicals: Trends, priorities, and optimization strategies-A review

Botanicals are widely used and marketed as food supplements or cosmetics with particular benefits for human health. Botanicals are products manufactured using natural components derived from plants, algae, fungi or lichens. Given the easy accessibility of such products, it is essential to ensure their safety by guaranteeing the absence of chemical or microbiological contamination. Furthermore, since botanicals are derived from natural products, they consist of a set of molecules called a phytocomplex, and it is important to develop standardized methods to ensure their reproducibility. Traditional approaches to the extraction of phytochemicals, as described in the monographs or pharmacopoeias of international authorities, guarantee product integrity with low levels of impurities and degradation products, but use large quantities of organic solvents with long timescales, high costs and environmental impact. A green chemistry approach is preferable to improve consumer safety, improve the extraction process and preserve the environmental status. This can be achieved by using advanced extraction methods that have proven effective in the extraction of natural molecules, such as microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE) combined with GRAS solvents or unconventional solvents, such as natural deep eutectic solvents (NADES). In the chemistry of natural products, the extraction phase is a fundamental step and the one most responsible for environmental sustainability. There are usually many parameters that need to be monitored and optimized to ensure the optimized conditions of these techniques. More than the empirical one variable at a time (OVAT) approach, Design of Experiments (DoE) is required to understand the effects of multidimensionality and interactions of input factors on the output responses of the extraction phase. To date, there are no specific metrics for the extraction phase, therefore, it is necessary to identify the parameters responsible for the environmental impact of the extraction phase and to optimize them in order to increase the eco-sustainability of the analytical process. The actual review provides a critical analysis of the current green extraction procedures in natural product chemistry aimed to provide insights into strategies to improve both extraction efficiency and ecosustainability

Couroupita guianensis bark decoction: From Amazonian medicine to the UHPLC-HRMS chemical profile and its role in inflammation processes and re-epithelialization

Ethnopharmacological relevance: In the Amazon rainforest, the shamans of the Mayantuyacu site use the healing virtues of decoctions and teas from different parts of the Couroupita guianensis Aubl. (Lecythidaceae) trees as remedies in Ashaninka medicine. However, composition of the remedy and the underlying mechanism remain unclear. Aim of the study: This study was designed to compare the metabolite profile of Couroupita guianensis bark decoction produced by Amazonian shamans with that obtained under standardised laboratory conditions and to investigate biological properties of both decoction and isolated constituents in skin wound healing process and inflammation. Materials and methods: The chemical analyses were carried out by Ultra-High-Performance Liquid Chromatography coupled with UV and High-Resolution Mass Spectrometry detectors (UHPLC-UV-HRMS). 1D- and 2D-NMR experiments were performed to identify the main decoction constituents. The decoction and pure compound effect on keratinocyte migration was determined by the in vitro wound healing model; the mechanism of action was elucidated by western blot analysis. Results: UHPLC-UV-HRMS analysis revealed the occurrence of polyphenolic compounds as catechins, ellagitannins and, notably, of unusual sulphated derivatives of ellagic acid isolated for the first time from Couroupita guianensis bark. A new natural sulphated molecule [4-(2″-O-sulphate- β-D-glucuronopyranosyl) ellagic acid] was identified as the potential active compound responsible for the efficacy of bark decoction stimulating wound healing in human HaCaT keratinocytes. The molecular mechanism involved the induction of pro-migratory pathways mediated by ERK and AKT phosphorylation and the increase of MMP2 expression in HaCaT cells. At the same time, the treatment inhibited inflammation interfering with NFkB activation. Conclusion: Beyond identifying a new bioactive compound, the overall results scientifically validate the traditional use of Couroupita guianensis bark decoction as an anti-inflammatory remedy. Moreover, the beneficial effects on keratinocytes suggest promising therapeutic applications in skin diseases