14 research outputs found

    Incorporation of lippia citriodora microwave extract into total-green biogelatin-phospholipid vesicles to improve its antioxidant activity

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    Phytochemicals from Lippia citriodora leaves were extracted by applying an innovative technology based on the use of microwaves, which represents an alternative method to extract bioactive substances. The obtained extract was incorporated into phospholipid vesicles in order to promote the antioxidant effect of the bioactive molecules present in L. citriodora extract. The extract was analyzed by High Performance Liquid Chromatography coupled to Time-Of-Flight mass spectrometer by electrospray (HPLC-ESI-TOF-MS) and different phytochemicals were detected and quantified. The whole extract was incorporated in liposomes, glycerosomes (liposomes modified with glycerol) and propylene glycol-containing vesicles (PG-PEVs). Moreover, a biopolymer obtained from fish by-product, that is Thunnus albacares skin, was added to improve the bioactivity of the formulations. The in vitro biocompatibility and the antioxidant efficacy of the extract in solution or loaded in the vesicles were tested in primary mouse embryonic fibroblasts (3T3). The results showed the superior bioactivity of the vesicle formulations over the aqueous solution of the extract, which points to an interesting strategy for the treatment of skin disorders

    Interfacing capillary electrophoresis and surface-enhanced resonance Raman spectroscopy for the determination of dye compounds

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    The at-line coupling of capillary electrophoresis (CE) and surface-enhanced resonance Raman spectroscopy (SERRS) was optimized for the separation and subsequent spectroscopic identification of charged analytes (dye compounds). Raman spectra were recorded following deposition of the electropherogram onto a moving substrate. To this end a new interface was developed using a stainless steel needle as a (grounded) cathode. The outlet end of the CE capillary was inserted into this metal needle; CE buffer touching the needle tip served as the electrical connection for the CE separation. A translation table was used to move the TLC plate at a constant speed during the deposition. The distance between the tip of the fused silica column and the TLC plate was kept as small as possible in order to establish a constant bridge-flow, while avoiding direct contact. The dyes Basic Red 9 (BR9), Acid Orange 7 (AO7) and Food Yellow 3 (FY3) were used as test compounds. After CE separation in a 20mM borate buffer at pH10, after deposition, concentrated silver colloid was added to each analyte spot, followed by irradiation with 514.5nm light from an argon ion laser to record the SERRS signal using a Raman microscope. Different types of silver colloids were tested: Lee-Meisel type (citrate), borate, and gold-coated silver. BR9 (positively charged) gave much more intense SERRS spectra than the two negatively charged dyes. For BR9 and AO7 the citrate-coated Lee-Meisel colloid yielded the most intense SERRS spectra. The CE-SERRS system was used to separate and detect the negatively charged dyes. Silver colloid and nitric acid (to improve adsorption) were added post-deposition. Even though their chemical structures are very similar, AO7 and FY3 could be readily distinguished based on their SERRS spectra. The limits of detection (S/N=3) of the CE-SERRS system ranged from 6.7×1

    Los fenoles del polen del género Zea

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    The variability of the pollen phenol composition of 32 populations of Zea mays subsp. mexicana, Zea mays subsp. parviglumis, Zea mays subsp. mays, Zea diploperennis, Zea perennis, and Zea luxurians from Mexico and Guatemala were analyzed. The phenol profiles were assessed by HPLC-DAD, and UPLC-TOF-MS. A total of 23 phenolics (four phenolic acids, 16 flavonols, and three dihydroflavonoids) were found. Quercetin glycosides (seven derivatives besides the quercetin aglycone itself) were the predominant compounds in the pollen of all analyzed species and subspecies. The major compound in all the samples, including the pollen of maize, was identified as quercetin-3,3'-O-diglucoside. The pollen of all the species and subspecies of Zea examined showed very similar patterns of accumulated phenols; however, variation in the minor compounds (phenolic acids and dihydroflavonoids) allowed to discern some inter- and intraspecific variations, although the split of Zea in the sections Luxuriantes and Zea was not clearly supported. The low level of variability of the pollen phenol profiles throughout the genus Zea supports the proposal that maize and some teosintes are conspecific groups, and indicates that the pollen phenol composition is highly conserved in the different taxa of Zea

    Establishment of pressurized-liquid extraction by response surface methodology approach coupled to HPLC-DAD-TOF-MS for the determination of phenolic compounds of myrtle leaves

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    Myrtus communis L. (myrtle) is native to the Mediterranean region and Western Asia. Its leaves have demonstrated its potential effect towards different bioactivities like anti-diabetic, anti-diarrheic, anti-ulcer, anti-cancer, among others. These activities have been associated with its phenolic content. In this sense, the aim of this work has been to develop a new pressurized-liquid extraction procedure (PLE), by using a response surface methodology (RSM), to evaluate the phenolic composition from myrtle leaves by HPLC-DAD-TOF-MS. Previously, different solvents such as methanol, ethanol, and acetone/water mixtures were tested by using ultrasound-assisted extraction (UAE) in order to select the most suitable one. Subsequently, a Box-Behnken design (BBD) was performed according to the effect of ethanol/water ratio (50, 75, and 100% (v/v)), temperature (50, 125, and 200 °C), and extraction time (5, 18, and 30 min). The optimal conditions achieved with the established method were 71% ethanol/water, 137 °C, and 19 min. The analysis of the obtained extracts by HPLC-DAD-TOF-MS allowed the characterization of 15 new compounds in myrtle leaves. Finally, high amounts of gallic and ellagic acid were found in the optimized PLE extracts (3.31 ± 0.03 and 3.88 ± 0.09 mg/g leaf dry weight (d.w.), respectively), and PLE reported greater recovery of total phenolic compounds than UAE (30 ± 1 and 22.4 ± 0.6 mg/g leaf d.w., respectively)

    Los fenoles del polen del género Zea

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    The variability of the pollen phenol composition of 32 populations of Zea mays subsp. mexicana, Zea mays subsp. parviglumis, Zea mays subsp. mays, Zea diploperennis, Zea perennis, and Zea luxurians from Mexico and Guatemala were analyzed. The phenol profiles were assessed by HPLC-DAD, and UPLC-TOF-MS. A total of 23 phenolics (four phenolic acids, 16 flavonols, and three dihydroflavonoids) were found. Quercetin glycosides (seven derivatives besides the quercetin aglycone itself) were the predominant compounds in the pollen of all analyzed species and subspecies. The major compound in all the samples, including the pollen of maize, was identified as quercetin-3,3'-O-diglucoside. The pollen of all the species and subspecies of Zea examined showed very similar patterns of accumulated phenols; however, variation in the minor compounds (phenolic acids and dihydroflavonoids) allowed to discern some inter- and intraspecific variations, although the split of Zea in the sections Luxuriantes and Zea was not clearly supported. The low level of variability of the pollen phenol profiles throughout the genus Zea supports the proposal that maize and some teosintes are conspecific groups, and indicates that the pollen phenol composition is highly conserved in the different taxa of Zea

    Activation of Human Brown Adipose Tissue by Capsinoids, Catechins, Ephedrine, and Other Dietary Components: A Systematic Review

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    Human brown adipose tissue (BAT) has attracted clinical interest not only because it dissipates energy but also for its potential capacity to counteract obesity and related metabolic disorders (e.g., insulin resistance and dyslipidemia). Cold exposure is the most powerful stimulus for activating and recruiting BAT, and this stimulatory effect is mediated by the transient receptor potential (TRP) channels. BAT can also be activated by other receptors such as the G-protein-coupled bile acid receptor 1 (GPBAR1) or beta-adrenergic receptors. Interestingly, these receptors also interact with several dietary components; in particular, capsinoids and tea catechins appear to mimic the effects of cold through a TRP-BAT axis, and they consequently seem to decrease body fat and improve metabolic blood parameters. This systematic review critically addresses the evidence behind the available human studies analyzing the effect of several dietary components (e.g., capsinoids, tea catechins, and ephedrine) on BAT activity. Even though the results of these studies are consistent with the outcomes of preclinical models, the lack of robust study designs makes it impossible to confirm the BAT-activation capacity of the specified dietary components. Further investigation into the effects of dietary components on BAT is warranted to clarify to what extent these components could serve as a powerful strategy to treat obesity and related metabolic disorders.Diabetes mellitus: pathophysiological changes and therap

    Development of advanced phospholipid vesicles loaded with Lippia citriodora pressurized liquid extract for the treatment of gastrointestinal disorders

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    Pressurized liquid extraction was performed to obtain a phytocomplex from Lippia citriodora leaves rich in bioactive compounds. The extract was loaded in phospholipid vesicles to improve its protective effect against oxidative stress in the intestine. The phytochemicals were identified and quantified by HPLC-ESI-TOF-MS. The extract was incorporated in liposomes and penetration enhancer-containing vesicles (PEVs) modified with glucidex, a dextrin, and a biopolymer obtained from Chimaera monstrosa. The PEVs were smaller than liposomes (~150 vs 370 nm) and more stable, according to accelerated aging tests. The integrity of the vesicles in acidic or neutral pH and high ionic strength or in milk whey was assessed. The cytocompatibility of the formulations and their ability to protect Caco-2 cells against oxidative stress were confirmed in vitro and compared with two commercial extracts of L. citriodora. The results confirmed the suitability of formulations to be used in functional foods to protect the intestine from oxidative stress
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