Departamento de Química Física y Analítica
URI permanente para esta comunidadhttps://hdl.handle.net/10953/49
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Ítem Chemical profiling, antioxidant, enzyme inhibitory and molecular modelling studies on the leaves and stem bark extracts of three African medicinal plants(Elsevier, 2019-05-22) Sadeer, Nabeelah Bibi; Llorent-Martínez, Eulogio; Bene, Kouadio; Mahomoodally, Mohamad Fawzi; Mollica, Adriano; Sinan, Kouadio Ibrahime; Stefanucci, Azzurra; Ruiz-Riaguas, Alba; Fernández-de-Córdova, María Luisa; Zengin, GokhanAfrica is famous for its floral biodiversity, exploited by local people for therapeutic purposes. However, such plants need to be scrutinised scientifically for the presence of bioactive compounds and possible biological properties. This study attempts for the first time to highlight the pharmacological and phytochemical profile of extracts prepared from leaves and stem barks of three African plants (Macaranga hurifolia Beille, Sterculia tragacantha Lindl. and Zanthoxylum gilletii (De Wild.) P. G. Waterman. The extracts were tested for antioxidant and enzyme inhibitory effects. Free radical scavenging, metal chelator, reducing power and phosphomolybdenum assays were performed to evaluate antioxidant effects. To identify enzyme inhibitory effects, cholinesterases (acetylcholinesterase (AChE) and butrylcholinesterase (BChE)), tyrosinase, alpha-amylase and alpha-glucosidase were selected as target enzymes. High performance liquid chromatography-Electrospray tandem mass spectrometry (HPLC-ESI-MS) technique was also used for chemical profiling. ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) and DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging assays showed that the stem barks of all three African plants were better scavenger than leaf extracts. Sterculia tragacantha was found to be a better metal chelator (64.10 ± 4.66 mg EDTAE/g) among the studied plants. All extracts exhibited good clinical enzyme inhibitory activities. The stem bark of S. tragacantha exhibited the best acetylcholinesterase activity compared to the other plants. HPLC-ESI-MS characterization showed that the most abundant compounds in stem bark were flavonoids in M. hurifolia (4.2 ± 0.2 mg/g DE), proanthocyanidins in S.tragacantha (42 ± 1 mg/g DE) and similar concentrations of phenolic acids and flavonoids in Z. gilletii (2.8–3.1 mg/g DE). Based on the biological activity, the most abundant and relevant bioactive compounds in the extracts were studied using molecular modelling approach against tyrosinase. The studied African plants showed good antioxidant and enzymatic propensities and thus can be considered as potential bioresources for future development of nutraceuticals and/or for pharmaceutical applications.Ítem Comparative study of the phytochemical and mineral composition of fresh and cooked broccolini(Elsevier, 2019-11-21) Llorent-Martínez, E.J.; Ortega-Vidal, J.; Ruiz-Riaguas, A.; Ortega-Barrales, P.; Fernández-de Córdova, M.L.Broccolini is originated from crossing the regular broccoli with Chinese kale. Consequently, it has similar properties to these vegetables, but other very particular characteristics. Its consumption has increased in the last few years and, consequently, there have been some studies related to its quality parameters and the influence of different cooking methods. Nevertheless, changes on its phenolic composition and mineral content originated by its cooking have not been investigated in-depth so far. Here we report the phytochemical profile of broccolini before and after boiling, steaming, and griddling cooking treatments. The mineral content and phytochemicals were assessed by inductively coupled plasma-mass spectrometry (ICP-MS) and high performance liquid chromatography-mass spectrometry (HPLC-MS), respectively. The main phenolics (mainly hydroxycinnamic acid derivatives from caffeic, coumaric, ferulic and sinapic acids) were quantified. Three oxylipins, three flavonoid glycosides and the glucosinolate glucobrassicin were also identified. ABTS and DPPH assays were also used as screening methods to assess the antioxidant potential of broccolini. A significant loss of the phenolic compounds and a reduction of the antioxidant activity were observed after the three cooking methods. Clear disadvantages were detected when broccolini was boiled, namely high losses of phenolic acids and derivatives (70%). Steaming and griddling also led to a significant loss of phenolics (50%) from fresh broccolini. The mineral content of this vegetable after domestic cooking procedures is also reported for the first time, calculating the contribution of broccolini consumption to official daily recommendations.Ítem Parentucellia latifolia subsp. latifolia: A potential source for loganin iridoids by HPLC-ESI-MSn technique(Elsevier, 2019) Llorent-Martínez, Eulogio; Fernández-de-Córdova, María Luisa; Zengin, Gokhan; Bahadori, Mir Babak; Aumeeruddy, Muhammad Zakariyyah; Rengasamy, Kannan RR; Mahomoodally, Mohamad FawziThis study attempts to compare the pharmaceutical potential (antioxidant and key enzyme inhibition of clinical relevance) of organic and aqueous extracts of Parentucellia latifolia (L.) Caruel subsp. latifolia (L.) Caruel as well as phytochemical composition. The phytochemical compounds were evaluated by spectrophotometric methods (for total amounts) and HPLC-ESI-DAD-MSn (for individual compounds). The extracts were screened for antioxidant abilities by in vitro assays. Inhibition effects were also investigated against a set of enzymes linked to major health problems. Generally, the methanol (MeOH) and aqueous extracts displayed higher scavenging abilities on radicals and reductive effects when compared with the ethyl acetate (EtOAc) extract. On the other hand, the EtOAc extract was the most active inhibitor on cholinesterases (1.81–1.88 mg GALAE/g), amylase (0.70 mmol ACAE/g), glucosidase (2.85 mmol ACAE/g) and lipase (33.24 mg OE/g). The highest TPC was observed in the aqueous extract (25.07 mg GAE/g) while MeOH extract possessed the highest level of TFC (44.15 mg RE/g) and TPAC (3.46 mg CE/g). LC-MSn metabolite profiling indicated that loganin and its isomers, rutin, and luteolin-O-hexoside were the most abundant compounds. Our results suggest that P. latifolia may be valuable source of phytoagentsfor the management of noncommunicable diseases.Ítem Phenolic Analysis and In Vitro Biological Activity of Red Wine, Pomace and Grape Seeds Oil Derived from Vitis vinifera L. cv. Montepulciano d’Abruzzo(MDPI, 2021-10-27) Mollica, Adriano; Scioli, Giuseppe; Della Valle, Alice; Cichelli, Angelo; Novellino, Ettore; Bauer, Marta; Kamysz, Wojciech; Llorent-Martínez, Eulogio; Fernández-de-Córdova, María Luisa; Castillo-López, Roxana; Ak, Gunes; Zengin, Gokhan; Pieretti, Stefano; Stefanucci, AzzurraGrape pomace is commonly considered a waste product of monovarietal red wine production. Methods: HPLC-DAD analysis was performed to determine the polyphenol and flavonoid contents of all the extracts obtained from Montepulciano d’Abruzzo red wine and grape skins whereas, GC-MS was applied to the determination of fatty acid composition in grape seeds oil. Biological characterization involves antioxidant and antimicrobial assays for all the extracts and seeds oil; Their ability to inhibit α-glucosidase, α-amylase, α-tyrosinase, and ChE enzymes was also detected, together with anti-inflammatory activity on wine, grape skin extracts, and seeds oil by lipoxygenase (5-LOX) and LPS-stimulated macrophage release assays. Data indicate significative polyphenols content (199.31 ± 7.21 mgGAE/g), antioxidant (CUPRAC assay (1036.98 mgTE/g)), enzymatic inhibition (α-tyrosinase: 151.30 ± 1.20 mgKAE/g) and anti-inflammatory activities for wine-organic extract 2, while the antimicrobial activity of grape skin decoction is higher than those reported by wine extracts on three bacterial strains. Interestingly only dealcoholized wine and wine-aqueous extract exerts inhibitory effects on α-glucosidase (20.62 ± 0.23 mmolACAE/g and 19.81 ± 0.03 mmolACAE/g, respectively), while seeds oil is rich in oleic and linoleic acids. These results confirm the strong antioxidant properties of Montepulciano d’Abruzzo grape pomace, suggesting the potential use of this waste product as functional food supplements in the human diet and in cosmeceutics.Ítem Phenolic profile and antioxidant activity of Jasonia glutinosa herbal tea. Influence of simulated gastrointestinal in vitro digestion(Elsevier, 2019-02-28) Ortega-Vidal, J.; Ruiz-Riaguas, A.; Fernández-de Córdova, M.L.; Ortega-Barrales, P.; Llorent-Martínez, E.J.In order to value J. glutinosa DC (rock tea), we characterised its phenolic profile and antioxidant activity. The study was performed in aqueous extracts before and after a simulated in vitro digestion to obtain data regarding phenolics bioavailability. Methanolic extracts were also analysed for comparison purposes. Phytochemical profiles were determined by high-performance liquid chromatography with mass spectrometric detection, whereas total phenolic content (TPC) and antioxidant assays were performed by conventional spectro-photometric methods. The most abundant compounds were dicaffeoylquinic acids, representing more than 90%of phenolics in tea infusions. Statistically significant differences were observed for all parameters except for TPC in methanol and aqueous extracts. Both phenolics amount and antioxidant activities were lower after the in vitro digestion of the infusions. However, although phenolics were lost during the simulated digestion, rock tea is still a good source of bioactive compounds with potential applications in the pharmaceutical or nutraceutical industries.Ítem Preliminary Phytochemical Screening and Antioxidant Activity of Commercial Moringa Oleifera Food Supplements(MDPI, 2023-01-02) Llorent-Martínez, Eulogio J.; Gordo-Moreno, Ana I.; Fernández-de Córdova, María Luisa; Ruiz-Medina, AntonioMoringa oleifera has been reported to possess a high number of bioactive compounds; hence, several food supplements are commercially available based on it. This work aimed to analyze the phytochemical composition and antioxidant activity of commercial food supplements. The phenolic composition of methanolic extracts was determined by using high-performance liquid chromatography with diode-array and electrospray ionization mass spectrometric detection (HPLCDAD- ESI-MSn), and the antioxidant activity was assessed by ABTS + and DPPH assays. Thirty-three compounds were identified, and all the main compounds were quantified, observing that the main contribution to the phenolic profile was due to kaempferol and quercetin glucosides. The antioxidant activity in both assays agreed with the phenolic content: the higher the phenolic levels, the higher the antioxidant activity. The obtained results were compared with those previously published regarding Moringa oleifera leaves to establish the potential benefits of food supplement consumption in the diet.Ítem Protocols for extraction of pesticide residues(Springer, 2020-12-22) Fernández de Córdova, María Luisa; Llorent Martínez, Eulogio JoséOver the past few years, the presence of pesticides in foods has received growing attention as one of the main food safety problems. Many countries and health organizations have dictated increasingly stringent regulations on the maximum residue limits for pesticides in foodstuffs, which are based on sensitive and trustworthy methods for pesticide residue analysis. Pesticides can also reach surface water through runoff from treated plants and soil, contaminate groundwater, soil, ground and grass and be toxic to non-target organisms. Therefore, it is necessary to develop highly selective methods of analysis that can ensure accurate and precise results with sufficiently low detection limits for a wide range of pesticides. Due to the large number of pesticides on the current market, multiclass and multiresidue methods are certainly the best way to address the problem of pesticide analysis and, in recent years, the general tendency has been the development of increasingly sensitive, accurate, precise and rapid methods. Despite the enormous progress made in the development of highly efficient analytical instrumentation for pesticide determination in samples of a very different nature, in most cases a pretreatment of the sample is still required to extract, isolate and concentrate the target compounds since it is generally not possible to directly manipulate the sample. Sample preparation often includes a cleanup step in order to remove non-specific matrix co-extractives, especially for analysis of very complex matrices such as foodstuffs and environmental samples, which also brings the analytes to an appropriate concentration level. Conventional sample treatment techniques are efficient, but they entail drawbacks such as the employ of toxic organic solvents that cause environmental contamination and additional operational costs for waste treatment, complicated procedures that require a lot of time, and difficulty in automation. Therefore, in recent years a lot of techniques have been developed in order to miniaturize and simplify the sample treatment, and reduce the amount of organic solvents used for meeting the requirements of green chemistry. Nevertheless, the pesticide residue analysis is an ongoing challenge mainly due to low concentration of pesticides, as well as the large quantities of compounds in the matrix that can be co-extracted, often giving rise to errors and damage to analytical instrumentation. In this chapter, the main classical and advanced methodologies available for the treatment of food and environmental samples for analysis of pesticide residues are summarized and explained. These techniques include: liquid-liquid extraction, Soxhlet extraction, supercritical fluid extraction, microwave-assisted extraction, pressurized liquid extraction, gel permeation chromatography, solid-phase extraction, matrix solid-phase dispersion, solid-phase microextraction, QuEChERS, stir bar sorptive extraction, and liquid-phase microextraction. Their advantages, drawbacks and future perspectives are also discussed.