This study presents a detailed characterization of 27 honey samples from the Tara Mountain region in Serbia using different comprehensive techniques and methods. The types of the honey samples were ...defined as monofloral (4 samples), honeydew (5 samples) and polyfloral (18 samples) honey based on determined polyphenol content, antioxidant activity, electrical conductivity and melissopalynological analyses. Physicochemical parameters such as pH (4.13–4.94), diastase activity (24.20–41.70 DN), acidity (14.60–29.70 meq/kg), content of 5-(hydroxymethyl)furfural (in range below 5, up to 16.90 mg/kg), sucrose (0.20–3.90 g/100 g), and moisture content (15.01–19.23%) confirmed the required quality of the honey samples. Sensory analysis revealed honey characteristics favorable to consumers. Analyses of 19 phenolic compounds using ultra-high-performance liquid chromatography with a diode-array detection and triple quadrupole mass spectrometry (UHPLC-DAD-MS/MS) revealed six phenolic acids and 13 other compounds from the group of flavonoids and their glycosides. In all the samples the highest content was determined for
p
-coumaric acid, followed by caffeic acid and pinocembrin. Besides total phenolic content and radical scavenging activity, antimicrobial activity was also examined. Most honey samples showed bactericidal activity against
Staphylococcus aureus
and bacteriostatic activity against
Escherichia coli
, while none of the honey samples inhibited the growth of
Candida albicans
. Chemometric analyses were applied for an in-depth study of the results to further evaluate the characteristics of the honey samples studied. Principal component analysis (PCA) was used for assessing the differences in physicochemical parameters, polyphenols content and antioxidant capacity between honey samples. The unrooted cluster tree was used to group the samples based on the melissopalynological analyses.
Raspberries are considered valuable fruits due to their high levels of nutrients and phytochemicals, which have many beneficial effects on humans. As many external factors affect the composition of ...these fruits (the type of cultivation, soil characteristics, ripeness, storage time and post-harvest technologies, cultivar/genotype, and climatic conditions), the goal of this study was to analyze different raspberry cultivars grown in Norway. Considering that Norway is a country with specific climatic conditions, as well as has a limited period of fruit vegetation, another important goal of this study was also to compare raspberries from different Norwegian areas, as well as different grown cultivars. Modern analytical techniques, such as high-performance anion-exchange liquid chromatography with pulsed amperometric detection (HPEAC-PAD), ultra-high-performance liquid chromatography with diode array detector coupled to triple quadrupole mass spectrometry (UHPLC-DAD MS/MS), and inductively coupled plasma–optical emission spectrometry (ICP-OES), provided a detailed examination of the raspberry extract samples. Based on their high levels of minerals (especially N, P, and K), organic acids (predominantly citric and malic acids), sugars (glucose, fructose, sucrose, and galactose), and polyphenols (ellagic acid, syringic acid, quercetin, and rutin), Norwegian raspberries could be considered fruits with increased health-beneficial compounds. The chemical composition of the studied cultivars depended on the locality of growth.
Using modern analytical techniques, a comprehensive study of the chemical composition of fruits from apple cultivars grown in Western Norway during 2019 and 2020 was done. Metals, sugars, organic ...acids, antioxidant tests, and polyphenol content have been observed. In all investigated samples, the most dominant sugars were glucose, fructose, and sucrose. Among 11 tested organic acids, the dominant was malic acid, followed by citric and maleic acid. The most common metal was potassium, followed by magnesium and zinc. The quantification of polyphenols showed that among the 11 quantified polyphenols, chlorogenic acid, quercetin 3-
O-
rhamnoside, quercetin 3
-O
-glucoside, quercetin, and phlorizin were the most abundant. A detailed study of the polyphenolic profile of nine investigated apple samples provided 30 identified polyphenolic compounds from the class of hydroxybenzoic and hydroxycinnamic acids, flavonoids, and dihydrochalcones. In addition to the identified 3-
O
-caffeoylquinic acid, its two isomers of 5-
O
-caffeoylquinic acid and three esters were also found. Present polyphenols of the tested apples provided significant data on the quality of Norwegian apples, and they contribute to the distinguishing of these apple samples.
Malta, a country renowned for its honey, has not been extensively mentioned in studies based on honey. In addition to many parameters, the collection period affects honey quality, precisely due to ...the different floral composition that exists during a certain season. Therefore, the significance of this study refers to the provision of data on honey from Malta collected during the autumn, spring, and summer seasons. Melissopalynological analysis, determination of physicochemical parameters, and the use of analytical chromatographic methods enabled detailed analysis of this honey. Principal component analysis (PCA) provided the differentiation of Maltese honey depending on the harvest season. Lotus pollen, followed by Eucalyptus, predominated in all honey samples. Characteristic compounds for summer honey were pinocembrin, galangin, kaempferol, chrysin, p-hydroxybenzoic acid, vanillic acid and maltotriose, while quercetin 3-O-galactoside, ferulic acid, ellagic acid, protocatechuic acid, luteolin 7-O-glucoside and melibiose were specific for autumn honey. A higher amount of p-coumaric acid, genistein, catechin, as well as the content of many sugars were found in spring samples. To the best of our knowledge, this is the first scientific work dealing with a detailed chemical analysis of Maltese honey
The aim of this study was to provide information on the phenolic and sugar profiles of different parts of the buckwheat plant, which can define that buckwheat is a functional food, with a high ...nutritional value and very useful for human health. Therefore, the extracts of buckwheat leaf, stem, and flower, as well as buckwheat grain were analysed for the content of polyphenol and antioxidant tests. The identification of a notable number of phenolic compounds and quantification of sugars in different parts of buckwheat indicates that buckwheat is a highly valuable plant. A total of 60 phenolic compounds were identified (18 cinnamic acid derivatives, 14 flavonols, 13 flavan-3-ols (including proanthocyanidins), 10 hydroxybenzoic acid derivatives, and 5 flavones) using ultra-high-performance liquid chromatography (UHPLC), coupled with a hybrid mass spectrometer which combines the Linear Trap Quadrupole (LTQ) and OrbiTrap mass analyzer. The highest number of phenolic compounds was found in the analysed buckwheat flower sample, and then in the leaf, followed by the grain and the stem. In addition, the sugar profile of buckwheat leaf, stem, flower and grain, as well as the buckwheat pollen and the nectar was analysed. Hence, 16 sugars and 5 sugar alcohols were detected by the high-performance anion exchange chromatography (HPAEC) with a pulsed amperometric detector (PAD). Sucrose was found in a significant amount with the highest content in buckwheat leaf. Trisaccharides had similar accumulation in the sample extracts, while disaccharides dominated in buckwheat leaf, followed by nectar and pollen. The sugar alcohols showed the highest content in buckwheat grain, where erythritol was predominant. The obtained results show that buckwheat is very rich in phenolic compounds and sugars. In addition to grain, the other parts of the buckwheat plant can be used as a very good source of different classes of phenolic compounds. This study provides useful information on the distribution of phytochemicals in different parts of the buckwheat plant, which contribute to the maintaining of the status of buckwheat as a functional food.
The aim of this study was to provide information on the phenolic and sugar profiles of different parts of the buckwheat plant, which can define that buckwheat is a functional food, with a high nutritional value and very useful for human health.
A focus of research in recent years is the comparison of honey as the final product of bees with pollen and nectar of the plant from which the honey originates, as the main food source for bees. ...Buckwheat honey is recognized as a nutritionally valuable product, which provides a scientifically proven health benefit and is confirmed as a functional food. The quality of this type of honey is attributed to high levels of phytochemicals in buckwheat. The purpose of this study was the examination of similarity between buckwheat honey and buckwheat nectar and pollen, as well as simultaneous investigation of their chemical profiles and the origin of the honey. The phenolic profile of buckwheat pollen showed a lower number of flavonoids and phenolic acids than those of nectar and honey samples, but confirmed the presence of the most characteristic polyphenols derived from the buckwheat plant. The notable difference was found to be the presence of (epi)catechin units, its galloylated derivatives and procyanidin dimers, which were not present in honey. Honey polyphenols displayed a pronounced correlation with those of nectar, but not with those of pollen. Finally, by comparing the polyphenolic profiles of honey, nectar and pollen sharing the same geographical origin, new data could be provided for a potential assessment of the botanical origin of buckwheat honey.
The research subject of this paper was a detail physicochemical analysis of 28 honey samples from the northern part of Montenegro. The honey from Montenegro has not been previously studied in such ...detail. Differentiation between samples, such as honeydew honey and polyfloral honey, was based on electrical conductivity, which was higher than 0.8 mS cm
−1
for honeydew honey, as was expected. Other investigated physicochemical parameters (water content, free acids, diastase activity, hydroxymethylfurfural (HMF) content and sugar content) have shown great similarity for all honey samples. The main interest of this study was the identification and quantification of phenolic compounds using ultra-high performance liquid chromatography (UHPLC) with mass spectrometry detection. The results show that honey samples are very rich in phenolic compounds, especially quercetin. Among the 31 quantified phenolic compounds, the most dominant were phenolic acids. The highlight was based on
p
-hydroxybenzoic acid,
p
-coumaric acid, caffeic acid and ferulic acid. Considering polyphenolic compounds and sugar content, a high nutritional value can be observed in all samples, with an emphasis on polyfloral honeys, as was confirmed with principal component analysis (PCA). In addition, all honey samples were tested for total phenolic content (TPC) and radical scavenging activity (RSA). The results indicate the higher antioxidant ability of honeys from Montenegro in comparison to some honey samples from other countries in the region.
The research subject of this paper was a detailed physicochemical analysis of 28 honey samples from the northern part of Montenegro.
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•C. comatus mycelium have ability to grow with vanadate.•Vanadate changes sugar phosphate content in the eukaryotic cell of fungus C. comatus.•In the eukaryotic cell of C. comatus ...vanadate is present as monomer.•Reduction of vanadate to vanadyl occurs inside the cell.•Vanadyl uptake is negligible compared to vanadate.
Vanadate is proposed to play a pivotal role in application of edible fungus Coprinus comatus for medical purposes. In this study the concentration of extracellular vanadate acceptable for the submerged cultivation of C. comatus mycelium was established. The mycelium could grow, and overcome vanadate toxic effects, up to the concentration of 3.3 mM. Moreover, in this condition, at the end of the exponential phase of growth, biomass yield was almost identical to that in the control. 31P NMR spectroscopy showed that addition of 10 mM vanadate to the mycelium in the exponential phase of growth provoked instantaneous increase of a sugar phosphates level which could be related to changes in activities of glycolytic enzymes. Exposure to higher vanadate concentration was toxic for the cell. 51V NMR measurements revealed that monomer of vanadate is present in the cytoplasm causing the metabolic changes. C. comatus has also capacity for vanadate reduction, as shown by EPR measurements, but vanadyl uptake is significantly less comparing to vanadate.
The micellization behavior and foamability of a mixture of anionic surfactant sodium laureth sulfate (SLES) and nonionic polysorbate surfactants commercially available as Tween series were ...investigated. The mole fraction and the structure of the hydrophobic part of various polysorbates affect the critical micellar concentration (CMC) and foam height and stability of anionic surfactant. Experimental values of CMC were determined by measuring specific conductivity at 25°C and foam height and stability by modified Ross–Miles method at 23°C. The negative deviation of the experimentally determined CMC from theoretical values for ideal mixed micelle indicate non-ideal mixing behavior due to synergism as a consequence of attractive interactions between the individual surfactants in formed micelles. Thus synergism increase with increasing of both the mole fraction and length of hydrophobic tail of examined Tween in SLES/Tween mixtures. Foam height and stability significantly decrease with increasing length of the hydrophobic tail of Tween surfactants and their mole fractions in the binary mixture.
ACTH stimulation is the standard test for assessment of adrenal
function. It was suggested that the low dose (1 μg) would be more
sensitive for detecting mild secondary adrenal insufficiency than the
...usual dose of 250 μg. The aim of this study was to find the optimal
diagnostic criteria and to compare standard dose test (SDT) with the
low dose test (LDT). A group of patients treated with corticosteroids
for the 6 months was considered to have hypothalamo-pituitary-adrenal
impairment. Studies were performed in 14 corticosteroid-treated and 28
control subjects in random order on 2 consecutive days. Tests were
analyzed using the receiver operating characteristic curve method. The
best test was cortisol increment at 15 min of the LDT. It was
significantly better than the cortisol concentration at 15 min of the
SDT, the best test during the SDT (receiver operating characteristic
curve area and 95% confidence interval: LDT, 0.997 and 0.956–0.999;
SDT, 0.827 and 0.662–0.929; P = 0.0113). For the
cortisol increment at 15 min of the LDT at 100% sensitivity, the
diagnostic value was 100 mmol/L, and the specificity was 96%.
Therefore, the LDT is superior to the standard dose test in the
assessment of secondary adrenal insufficiency.
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