Foods enriched with plants have gradually become an area of increasing research interest because plant ingredients may offer several positive effects on human health and the body. The aim of our study was to develop biscuits fortified with three different types of edible flowers (marigold, lavender, and rose) and examine their physical and antioxidant characteristics, as well as consumer acceptability. The antioxidant properties and characterization of biscuits highlighted that edible flowers may cause increased total polyphenol and total flavonoid yields, as well as DPPH radical scavenging activities.
View Article and Find Full Text PDFThe aim of the present study is to evaluate the antioxidant properties of wild blackberry fruits as well as their possible use in powdered form as a functional ingredient. For this, ultrasound-assisted extraction optimization, ripening stage evaluation, and wild blackberry powder incorporation into a real food matrix were applied. The optimum conditions for extraction were as follows: 60% MeOH, 20 min of extraction time, acidification with 0.
View Article and Find Full Text PDFGrapefruit peel contains a high concentration of naringin- a potent antioxidant with strong bioactive properties. In this study, a new type of functional chocolate fortified with grapefruit peel extract and different concentrations of aqueous methanol and ethanol were evaluated as extraction solvents. A new high-performance liquid chromatography (HPLC) method to analyze the naringin content of the fortified chocolates was developed with a recovery of 107% ± 3.
View Article and Find Full Text PDFAlthough wild fruits are significantly underutilized in most countries, they could be good sources of valuable bioactive compounds with antioxidant properties. Therefore the present study focused on the study of a conventional extraction technique (maceration with shaking; MAC) to extract natural antioxidants and anthocyanin colorants from six edible wild-growing fruits (European crab apple, bilberry, yellow-, red-, and purple-skinned greengage, and quince). One-factor-at-a-time (OFAT) methodology was chosen to investigate the influences of three different parameters (solvent type, extraction time and solvent acidity) on the total polyphenol contents (TPCs), total monomeric anthocyanin (TMA) contents, and antioxidant capacities, specifically ferric reducing power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activity (DPPH).
View Article and Find Full Text PDFNaringin is a flavonoid found primarily in citrus species with especially high concentrations being present in grapefruit (), bitter orange (), and pomelo (). Because of its many positive effects on human health, naringin has been the focus of increasing attention in recent years. Recently, conventional extraction methods have been commonly replaced with unconventional methods, such as ultrasound-assisted extraction (UAE) and other, more eco-friendly extraction methods requiring little-to-no environmentally harmful solvents or significantly less energy.
View Article and Find Full Text PDFThe goal of this study was to improve the extraction efficiency of rosmarinic acid (RA) from Lamiaceae herbs (lemon balm, peppermint, oregano, rosemary, sage, and thyme) using various extraction techniques (maceration with stirring, MAC; heat reflux, HRE; and microwave-assisted extraction, MAE) and extraction conditions (solvent acidity, solvent type, extraction time and temperature). The RA content was measured by high-performance liquid chromatography with diode-array detection (HPLC-DAD) under test conditions. Our results showed that extraction with acidified aqueous ethanol (EtOH-HO-HCl, 70:29:1, v/v/v) was the best choice for the recovery of RA compared to other solvent systems.
View Article and Find Full Text PDFHR-CS-GFAAS methods were developed for the fast determination of Cu in domestic and commercially available Hungarian distilled alcoholic beverages (called pálinka), in order to decide if their Cu content exceeds the permissible limit, as legislated by the WHO. Some microliters of samples were directly dispensed into the atomizer. Graphite furnace heating programs, effects/amounts of the Pd modifier, alternative wavelengths (e.
View Article and Find Full Text PDFKinetics of pre-column derivatization with 9-xanthydrol for the determination of ethyl carbamate (EC) in wine by a previous high performance liquid chromatographic method with fluorescence detection was studied and further developed. The life-time of the derivatized product and its excitation/absorption spectra were systematically investigated. Using low acidity (pH=2.
View Article and Find Full Text PDFSolid sampling (SS) graphite furnace atomic absorption spectrometry (GFAAS) and solution-based (SB) methods of GFAAS, flame atomic absorption spectrometry (FAAS), inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS) were elaborated and/or optimized for the determination of Cr, Fe and Mn trace elements used as dopants in lithium niobate optical crystals. The calibration of the SS-GFAAS analysis was possible with the application of the three-point-estimation standard addition method, while the SB methods were mostly calibrated against matrix-matched and/or acidic standards. Spectral and non-spectral interferences were studied in SB-GFAAS after digestion of the samples.
View Article and Find Full Text PDFMicroanalytical methods suitable for the determination of Fe, Cu in HT-29 (human colon adenocarcinoma) cells treated with different iron compounds (Fe(II) sulfate, Fe(III) chloride, Fe(III) citrate and Fe(III) transferrin) and cultured in medium supplemented or not with 10% (v/v) fetal calf serum (FCS) by total reflection X-ray fluorescence spectrometry (TXRF) and simultaneous graphite furnace atomic absorption spectrometry (GF-AAS) were developed. The developed TXRF method was also suitable for Zn determination in the samples. The main advantage of the proposed methods is the execution of all sample preparation steps following incubation and prior to the elemental analysis in the same Eppendorf tubes.
View Article and Find Full Text PDFA novel electrothermal atomic absorption spectrometry (ETAAS) method was developed for the halogenation of refractory sample components (Er, Nd and Nb) of lithium niobate (LiNbO(3)) and bismuth tellurite (Bi(2)TeO(5)) optical single crystals to overcome memory effects and carry-over. For this purpose, the cleaning step of a regular graphite furnace heating program was replaced with a halogenation cycle. In this cycle, after the graphite tube cooled to room temperature, a 20 μL aliquot of liquid carbon tetrachloride (CCl(4)) was dispensed with a conventional autosampler into the graphite tube.
View Article and Find Full Text PDFA multi-element graphite furnace atomic absorption spectrometry (GFAAS) method was elaborated for the simultaneous determination of As, Cd, Cu, and Pb in wine samples of various sugar contents using the transversally heated graphite atomizer (THGA) with end-capped tubes and integrated graphite platforms (IGPs). For comparative GFAAS analyses, direct injection (i.e.
View Article and Find Full Text PDFPhotoacoustic (PA) spectroscopy in the visible wavelength region was shown to be suitable for a direct (no preparatory steps involved) quantification of sunset yellow (E110) colour in effervescent multi-vitamin tablets. Measurements on powdered tablets containing E110 were performed at 480 nm at which wavelength this synthetic colour shows appreciable absorbance. The PA data obtained were compared to the results acquired by diffuse reflectance spectroscopy and conventional spectrophotometry.
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