Comparative Study of the Antioxidant and Enzyme Inhibitory Activities of Two Types of Moroccan Euphorbia Entire Honey and Their Phenolic Extracts.

Honey is a natural food product very famous for its health benefits for being an important source of antioxidant and phenolic compounds. Euphorbia honeys obtained from different regions of Morocco were evaluated for their ability to inhibit acetylcholinesterase, lipoxygenase, tyrosinase and xanthine oxidase activities. Their antioxidant properties were evaluated using the: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity, nitric oxide scavenging activity (NO) and scavenging ability of superoxide anion radical. Then, the phenolic extracts of the same entire honey samples were evaluated by liquid chromatography coupled to diode array detection and mass spectrometry (LC-DAD-MS) and tested for the biological activities previously evaluated on the entire honeys, in order to conduct a comparative study between both (honey and phenolic extracts). The chromatographic profiles for the studied Euphorbia honey extracts were different. Phenolic compounds gallic acid, 4-hydroxybenzoic acid and p-coumaric acid were detected in all samples, whereas kampferol was only present in two samples. Physicochemical parameters and total phenolic content were also determined. Entire honey that recorded the highest rate of phenols was sample M6 (E. resinifera) = 69.25 mg GAE/100 g. On the other hand, the phenolic extracts had better antioxidant and enzyme inhibitory activities than the entire honeys, regardless the monofloral honey type. In conclusion, the studied Euphorbia honeys may have a great potential as antioxidant, anti-inflammatory and anti-tyrosinase sources for pharmaceutical and cosmetic applications.

Formulation of goat's milk yogurt with fig powder: Aromatic profile, physicochemical and microbiological characteristics.

Fig (Ficus carica L.) is an excellent source of sugars, dietary fibers, minerals, vitamins, organic acids and phytochemicals. The aim of the present work was to investigate the effect of fig powder supplement, as a natural sweetener and flavoring agent, on the physicochemical, microbiological and sensory characteristics of goat's milk yogurt. It aimed also to determine antioxidant capacity and volatile profile using gas chromatography/mass spectrometry (GC/MS) analysis. Pyrolysis-GC/MS (Py-GC/MS) was also used for the characterization of fig powder. Fig powder exhibited an important antioxidant activity against DPPH. Radical (IC50 = 1.92 ± 0.05 mg per mL). Volatile compounds, from several classes (acids, alcohols, aldehydes, esters, triterpenoids and others) were identified in fig powder. Py-GC/MS data revealed that degradation of fig powder macromolecules leaded to the formation of several aromatic and volatile compounds such as fatty acids, ketones, aromatic phenols, lactones among others. The addition of fig powder increased significantly (p < 0.05) the titrable acidity, the total solids, the carbohydrate content, and the total lactic acid bacteria count of yogurts. Likewise, fig powder supplement improved yogurt taste, texture and aroma and covered the unpleasant flavor of goat's milk. Thus, fig powder is a natural sweetener and flavoring agent that can be used to formulate a new stirred goat's yogurt of good quality.

Analytical characterization of the palette and painting techniques of Jorge Afonso, the great 16th century Master of Lisbon painting workshop.

In this work, a study on a set of paintings from the most significant altarpiece assigned to Master Jorge Afonso (c. 1470-1540) painting workshop is presented. This altarpiece is composed by fourteen paintings made to the church of Convento de Jesus, in Setúbal, Portugal, and was made circa 1517-19/1530, according to art-history. This set of paintings is compared to one of the other most important Portuguese altarpieces from the 16th century: the panels of the Round Church of the Convento de Cristo, in Tomar, made circa 1510-1515. The aim of this study is to characterize the wooden support, pigments, ground layers materials and technique used in Jorge Afonso workshop by means of complementary analyses. A dendrochronological approach was made in order to corroborate (or not) the historical date initially assigned. Infrared photography (IRP) and reflectography (IRR) allowed the study of the underdrawing technique and macro photography (MP) was used to recognize overlapping layers technique. Cross-sections from the paintings were examined by optical microscopy (OM), and analyzed by µ-X-ray diffraction (µ-XRD), Energy Dispersive X-ray Fluorescence spectroscopy (EDXRF), Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDS), micro-Raman spectroscopy (µ-Raman), micro-Fourier Transform Infrared spectroscopy (µ-FTIR), Pyrolysis Gas Chromatography Mass Spectrometry (py-GC/MS). The characterization of the palette and ground layers and the study of the overlapping of paint layers brought a new insight of the adopted painting techniques by the most important group of painters working in Portugal in the 16th century - the Lisbon workshop, leaded by Master Jorge Afonso.

Effect of edible coatings with essential oils on the quality of red raspberries over shelf-life.

BACKGROUND: The objective of the present work was to develop strategies for increasing the shelf-life of red raspberries (Rubus idaeus L.), by preventing microorganism growth. RESULTS: Fruits coated with alginate plus lemon essential oil (0.2%) or orange essential oil (0.1%) after 15 days of storage had less red skin than the remaining samples. The less red color verified in these samples was also coincident with the lower concentration of anthocyanins at the end of the experiment as well as the lower capacity for scavenging ABTS free radicals or quenching singlet oxygen. Cyanidin and pelargonidin glucosides were found in raspberries fruits. The edible coatings supplemented with the essential oil of orange either at 0.1% or 0.2% were very efficient for controlling yeast and mold growth after 15 days of storage. To control the development of aerobic mesophilic bacteria the use of essential oil of lemon 0.2% and essential oil of orange 0.1% were the most efficient. CONCLUSION: The application of the film improved post-harvest quality of raspberry, since the addition of essential oils of citrus films promoted to the inhibitory effect of fungi and bacteria growth after 15 days of storage, without changing quality parameters. © 2016 Society of Chemical Industry.

The liturgical cope of D. Teotónio of Braganza: material characterization of a 16th century pluviale.

A 16th century liturgical cope belonging to D. Teotónio of Braganza (collection of the Museum of Évora, ME 172/1) was selected for a material study. The cope is made of a variety of materials that include two different types of metal threads, dyed silk yarns, and vegetable yarns used in the weft. Several samples from different points representing the different metal thread types and colored silk yarns were collected. Stereomicroscopy (optical microscopy) and scanning electron microscopy were used for morphological analysis of the textile fibers and evaluation of metal thread degradation products. Evaluation of mordants and metal thread composition was carried out by energy-dispersive X-ray spectroscopy. Liquid chromatography with diode array and mass spectrometry detection was used for dye identification, which allowed the determination of three different red dye sources and one yellow dye source in the colored silk yarns. Although different fabrics were used in the manufacturing of the cope, similarities identified in the characterization of the materials suggest that a single workshop was involved in its making.

Extracting natural dyes from wool--an evaluation of extraction methods.

The efficiency of eight different procedures used for the extraction of natural dyes was evaluated using contemporary wool samples dyed with cochineal, madder, woad, weld, brazilwood and logwood. Comparison was made based on the LC-DAD peak areas of the natural dye's main components which had been extracted from the wool samples. Among the tested methods, an extraction procedure with Na(2)EDTA in water/DMF (1:1, v/v) proved to be the most suitable for the extraction of the studied dyes, which presented a wide range of chemical structures. The identification of the natural dyes used in the making of an eighteenth century Arraiolos carpet was possible using the Na(2)EDTA/DMF extraction of the wool embroidery samples and an LC-DAD-MS methodology. The effectiveness of the Na(2)EDTA/DMF extraction method was particularly observed in the extraction of weld dye components. Nine flavone derivatives previously identified in weld extracts could be identified in a single historical sample, confirming the use of this natural dye in the making of Arraiolos carpets. Indigo and brazilwood were also identified in the samples, and despite the fact that these natural dyes were referred in the historical recipes of Arraiolos dyeing, it is the first time that the use of brazilwood is confirmed. Mordant analysis by ICP-MS identified the widespread use of alum in the dyeing process, but in some samples with darker hues, high amounts of iron were found instead.

Application of sample disruption methods in the extraction of anthocyanins from solid or semi-solid vegetable samples.

Cassis, a commercial powder obtained from blackcurrant juice (Ribes nigrum L.), was used to optimize the anthocyanin extraction by matrix solid-phase dispersion (MSPD) and by sea sand disruption method (SSDM). The optimum eluent conditions were 5.0 mL of MeOH/H2O (1:1, v/v) at pH 2. The extracts were analyzed by HPLC with diode-array detection (DAD) and the extraction efficiency was evaluated by statistical comparison (analysis of variance, ANOVA-single factor) of the compounds peak areas. The extraction efficiency for the MSPD procedure was dependent on the chemical nature of the C18 material but the optimized procedure yielded results similar to those obtained by the inexpensive sea sand disruption method (SSDM). This procedure also compared favorably to a previously published liquid-liquid extraction method. The optimized sea sand method was then used in the anthocyanin extraction from red grapes (Vitis vinifera L.) and strawberries (Fragaria ananassa D.) yielding chromatographic profiles similar to those reported in the literature for these products.