Search results for "HPLC-UV"
showing 8 items of 8 documents
Stinging nettle (Urtica dioica L.) as a functional food additive in egg pasta: Enrichment and bioaccessibility of Lutein and β-carotene
2018
Abstract The use of stinging nettles as an ingredient in egg pasta has been evaluated with respect to food enrichment with carotenoids. Bioaccessibility of lutein and β-carotene has been estimated by dynamic simulation of the digestion process, with particular attention to duodenum and colon stages. Higher bioaccessibility for the two carotenoids occurs between 2 and 24 h of colonic fermentation and it is around 35% for lutein and 10% for β-carotene. However, the results reveal that the food matrix has a significant role in carotenoid release during the digestion process. In general, nettle enriched pasta has a lower carotenoid bioaccessibility than dietary supplement at duodenum and after …
Vaccinium macrocarpon (Cranberry)-Based Dietary Supplements: Variation in Mass Uniformity, Proanthocyanidin Dosage and Anthocyanin Profile Demonstrat…
2020
Vaccinium macrocarpon (syn. American Cranberry) is employed in dietary supplements (DS) with the aim to improve urinary tract well-being. This property is linked to the antiadhesion-activity of proanthocyanidins (PACs) against uropathogenic-bacteria. However, the current European legislation has been criticized for being weak and ineffective. Indeed, recent scientific works report mislabeled, contaminated, and adulterated supplements containing dangerous or unknown compounds, or sold at toxic doses. In this work, we analysed 24 DS that claim to contain cranberry, and to have a specific dosage of PACs. Our tests included the control of the good manufacturing practice according to the Europea…
Separation, isolation and stereochemical assignment of imazalil enantiomers and their quantitation in an in vitro toxicity test
2016
A simple method for the separation of the enantiomers of the fungicide imazalil was developed. Racemic imazalil was separated into its enantiomers with an enantiomeric purity of 99% using HPLC-UV with an enantioselective column (permethylated cyclodextrin) operated in reversed phase mode (water with 0.2% trimethylamine and 0.08% acetic acid and methanol). The absolute configuration of the separated enantiomers was assigned and unequivocally confirmed by optical rotation as well as by vibrational circular dichroism (VCD) and electronic circular dichroism (ECD) combined with ab-initio calculations. The same enantioselective column was also used to develop an HPLC-MS/MS method for the quantifi…
Fourier transform infrared determination of imidacloprid in pesticide formulations
2004
A simple method has been developed for Fourier Transform Infrared (FTIR) determination of Imidacloprid in pesticide formulations. Samples were diluted with CHCl3 and the FTIR spectra of samples and standards were obtained at a nominal resolution of 4 cm-1 from 4000 to 900 cm-1 accumulating 25 scans. Imidacloprid determination was based on the measure of either peak area from 1577 to 1567 cm-1 or peak height at 1572 cm-1, both corrected using a horizontal baseline defined at 1900 cm-1. The limits of detection achieved, of the order of 9 µg g-1, were appropriate for the determination of Imidacloprid in commercially available formulations. FTIR results were statistically comparable to those fo…
Color Stabilization of Apulian Red Wines through the Sequential Inoculation of Starmerella bacillaris and Saccharomyces cerevisiae
2021
Mixed fermentation using Starmerella bacillaris and Saccharomyces cerevisiae has gained attention in recent years due to their ability to modulate the qualitative parameters of enological interest, such as the color intensity and stability of wine. In this study, three of the most important red Apulian varieties were fermented through two pure inoculations of Saccharomyces cerevisiae strains or the sequential inoculation of Saccharomyces cerevisiae after 48 h from Starmerella bacillaris. The evolution of anthocyanin profiles and chromatic characteristics were determined in the produced wines at draining off and after 18 months of bottle aging in order to assess the impact of the different f…
Phytochemical-rich extracts of Helianthemum lippii possess antimicrobial, anticancer, and anti-biofilm activities
2022
Helianthemum lippii is a perennial shrubby plant growing in the sandy environments of Italy, Mediterranean countries of North Africa and Middle East. H. lippii is used in traditional medicine but there are very few reports referring to the phytochemical characterization, the ethnopharmacology, and the biological activity of H. lippii. The goal of this study was todetermine the phytochemical composition of different H. lippii extracts, cold (CME) and hot (HME) methanol, cold (CPEE) and hot (HPEE) petroleum ether, as well as to evaluate their anticancer and antimicrobial activities and biofilm formation reduction. Fifty-fours phytocompounds have been determined by HPLC-UV-ESI-QTOF-MS analysis…
HPLC-UV/Vis-APCI-MS/MS Determination of Major Carotenoids and Their Bioaccessibility from "Delica" (Cucurbita maxina) and "Violina" (Cucurbita moscha…
2018
Carotenoids are a widespread group of fat-soluble pigments, and their major nutritional importance comes from their pro-vitamin A activity and their antioxidant capacity. In this study, two different pumpkin cultivars (Cucurbita maxima, also named `Delica&rsquo
Harvesting canthinones: identification of the optimal seasonal point of harvest of Zanthoxylum chiloperone leaves as a source of 5-methoxycanthin-6-o…
2015
This article is focused on the seasonal variation in the contents of 5-methoxycanthin-6-one from the leaves of Zanthoxylum chiloperone (Rutaceae). Based on the pharmacological interest presented by 5-methoxycanthin-6-one, its seasonal variation in Z. chiloperone leaves was analysed in order to determine the best time for harvesting, optimising the 5-methoxycanthin-6-one content. The seasonal dynamics of canthinone alkaloids can be the key to improve the isolation from natural sustainable sources, such as leaves. Complementarily, this study describes the phytochemistry of leaf from this Ruraceae species.