Spray-drying Microencapsulation of an Extract from Tilia tomentosa Moench Flowers: Physicochemical Characterization and in Vitro Intestinal Activity.

Silver linden (Tilia tomentosa Moench, TtM) flowers possess several health-promoting properties, especially at the neurological level, such as intestinal relaxation activity associated with specific flavonols, particularly quercetin and kaempferol derivatives. However, such molecules are susceptible to degradation upon different triggers like heat, light and extreme pH values. To overcome the scarce stability of TtM flowers bioactive molecules and make them suitable for developing functional food and supplements, we applied microencapsulation. Spray-drying microencapsulation of TtM flowers extract was performed using three starch-derived wall materials: maltodextrin 12 DE (MD12) and 19 DE (MD19), and OSA-modified starch (OSA-S). The stability of total phenols, flavanols, and antioxidant capacity was monitored for 70 days under accelerated stress conditions (40 °C/70% RH) by HPLC and spectrophotometric methods, and the intestinal contractile activity was tested in a murine model. In comparison to MD12 and MD19, OSA-S stood out for the higher encapsulation efficiency of quercetin and kaempferol glycosides (+ 36-47% compared to MD12 and + 18-24% compared to MD19) and stability thereof (half-life on average + 30% compared to MD12 and + 51% compared to MD19). The intestinal contractile activity of OAS-S powders resulted comparable to the original extract, indicating that flavonols were biologically active and accessible. Our results underly the potential advantages of OSA-S encapsulated formulation as a functional ingredient for the development of nutraceutical products.

Characterization of herbal teas containing lime flowers - Tiliae flos by HPTLC method with chemometric analysis.

Linden trees are a source of food products called lime flowers (Tiliae flos), traditionally used in the form of infusion for the treatment of feverish colds and coughs. Lime flowers should include flowers of Tilia cordata Mill, T.x europaea L., and T. platyphyllos Scop. or a mixture of these. The aim of current research was to establish a fast, sensitive HPTLC (high-performance thin-layer chromatography) method that would allow the differentiation of material obtained from five species of lime occurring in Europe. The fingerprints for distinguishing these species were established, as well as a key for identification based on a visual evaluation of chromatograms. The results obtained were also subjected to chemometric analyses. It was shown that each species contains characteristic compounds i.e. linarin that can be used for their identification. The method developed can, in theory, be introduced for the quality control or authentication of linden flowers on the European market.

Nutlets of Tilia cordata Mill. and Tilia platyphyllos Scop. - Source of bioactive compounds.

The aim of this study was to analyse contents of phytosterols, carotenoids, tocochromanols and fatty acid composition in oil from nutlets of linden. Standard determination methods for these compounds were applied using liquid and gas chromatography. In the analysed oils from small and large-leaved lime the dominant acids included linoleic (53.1 and 54.1%), oleic (18.5 and 22.2%), palmitic (15.3 and 11.8%). Linden seed oil was characterised by very high contents of phytosterols (2-2.5 g/100 g). ß-Sitosterol was the dominant phytosterol (80-83%). Additionally squalene was detected at 806 and 607 mg/100 g, respectively, for Tilia cordata and T.platyphyllos. It was found that linden seed oil contains tocopherols (93%) and tocotrienols (7%). In terms of tocochromanol contents this oil is surpassed only by wheat germ oil. In terms of the α-T equivalent these oils contain 95 (Tilia cordata) and 50.6 mg/100 g vitamin E (Tilia platyphyllos).

Assessment of the anti-pathogenic effects of condensed tannin extracts using scanning electron microscopy.

Two different types of condensed tannins (CTs), which were extracted and purified from tilia (Tilia L.) and black locust (Robinia pseudoacacia), were studied and tested against two kinds of bacteria, including Gram-negative and Gram-positive, avian pathogenic E. coli (APEC) and Staphylococcus epidermidis (S. epidermidis) respectively, by minimal bactericidal concentrations (MBCs) and scanning electron microscopy (SEM). Both CT extracts were significantly effective (p ≤ 0.05) at MBCs of 5-10 mg CT/ml against APEC (Gram-negative), and at 1.25-5 mg CT/ml on S. epidermidis (Gram-positive). This indicated that the CTs were more potent against the Gram-positive than the Gram-negative bacteria. Further, SEM revealed that CTs caused mainly morphological deformations of the bacterial cells and some conjoined cell growth.

A mixture of quercetin 4'-O-rhamnoside and isoquercitrin from Tilia americana var. mexicana and its biotransformation products with antidepressant activity in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: The aerial parts of Tilia americana var. mexicana (Malvaceae, formerly Tiliaceae) or "sirimo" are used in Mexican traditional medicine for the relief of mild symptoms of mental stress, commonly referred to as "nerve diseases". Individuals use this plant to fall asleep, to calm states of nervous excitement, headaches, mood disorders, and general discomfort. Recent studies indicated that fractions standardized in their flavonoid content possess antidepressant activity in behavioral assays in mice. The present study aims to focus on the evaluation of the antidepressant effect of the mixture of two flavonoids (FMix), and its interaction with serotonergic drugs. Also, the pharmacological effect of the products of the metabolism of aglycone, quercetin, was evaluated in mice subjected to forced swimming test (FST) and open field test (OFT). MATERIALS AND METHODS: A methanol-soluble extract obtained from leaves of Tilia americana was fractionated in an open column chromatographic separation. One of the fractions contained FMix wich is constituted of the mixture of quercetin 4'-O-rhamnoside (1, 47%) y isoquercitrin (2, 53%). The mice were divided into the several following groups: FMix (0.01, 0.1, 0.5, 1.0, and 2 mg/kg); FMix (1.0 mg/kg) and agonist DOI (2.0 mg/kg); FMix (1.0 mg/kg) and antagonist ketanserin (KET, 0.03 mg/kg) of 5-HT2A receptors; FMix (1.0 mg/kg) and selective agonist 8-OH-DPAT (8-OH, 0.01 mg/kg); FMix (1.0 mg/kg) and antagonist WAY100635 (WAY, 0.5 mg/kg) of 5HT1 receptors; Phloroglucinol (PHL); 3,4-dihydroxy-phenyl acid (DOPAC); p-hydroxyphenyl acetic acid (p-HPAA); and m-hydroxyphenyl acetic acid (m-HPAA) were tested in FST or OFT. RESULTS: FMix induced dependent-dose antidepressant activity and, at the highest dose administered, a sedative effect was also observed. The 8-OH-DPAT, or the DOI, or the KET combination with FMix (1.0 mg/kg) induced a higher antidepressant effect than compounds alone; there was no effect exerted with WAY. The activity on OFT increased only with the FMix and KET combination. At the same time, the products of the aglycone metabolism of quercetin, that is, DOPAC and p-HPAA, decreased the immobility time of the mice in FST at 1.0 mg/kg, and a dose-curve was formed for these. CONCLUSION: The antidepressant effect of FMix could depend, at least in part, on the degradation products of quercetin and with a possible action mode through interaction with the serotoninergic system.

Branch-Localized Induction Promotes Efficacy of Volatile Defences and Herbivore Predation in Trees.

Induction of plant defences can show various levels of localization, which can optimize their efficiency. Locally induced responses may be particularly important in large plants, such as trees, that show high variability in traits and herbivory rates across their canopies. We studied the branch-localized induction of polyphenols, volatiles (VOCs), and changes in leaf protein content in Carpinus betulus L., Quercus robur L., and Tilia cordata L. in a common garden experiment. To induce the trees, we treated ten individuals per species on one branch with methyl jasmonate. Five other individuals per species served as controls. We measured the traits in the treated branches, in control branches on treated trees, and in control trees. Additionally, we ran predation assays and caterpillar food-choice trials to assess the effects of our treatment on other trophic levels. Induced VOCs included mainly mono- and sesquiterpenes. Their production was strongly localized to the treated branches in all three tree species studied. Treated trees showed more predation events than control trees. The polyphenol levels and total protein content showed a limited response to the treatment. Yet, winter moth caterpillars preferred leaves from control branches over leaves from treated branches within C. betulus individuals and leaves from control Q. robur individuals over leaves from treated Q. robur individuals. Our results suggest that there is a significant level of localization in induction of VOCs and probably also in unknown traits with direct effects on herbivores. Such localization allows trees to upregulate defences wherever and whenever they are needed.

Use of an Animal Model to Evaluate Anxiolytic Effects of Dietary Supplementation with Tilia tomentosa Moench Bud Extracts.

Anxiety disorders are common and complex psychiatric syndromes affecting a broad spectrum of patients. On top of that, we know that aging produces an increase in anxiety vulnerability and sedative consumption. Moreover, stress disorders frequently show a clear gender susceptibility. Currently, the approved pharmacological strategies have severe side effects such as hallucinations, addiction, suicide, insomnia, and loss of motor coordination. Dietary integration with supplements represents an intriguing strategy for improving the efficacy and the safety of synthetic anxiolytics. Accordingly, a recent article demonstrated that glyceric bud extracts from Tilia tomentosa Moench (TTBEs) exert effects that are consistent with anxiolytic activity. However, the effects of these compounds in vivo are unknown. To examine this question, we conducted behavioral analysis in mice. A total of 21 days of oral supplements (vehicle and TTBEs) were assessed by Light Dark and Hole Board tests in male and female mice (young, 3 months; old, 24 months). Interestingly, the principal component analysis revealed gender and age-specific behavioral modulations. Moreover, the diet integration with the botanicals did not modify the body weight gain and the daily intake of water. Our results support the use of TTBEs as dietary supplements for anxiolytic purposes and unveil age and gender-dependent responses.

Polyherbal Formulation Enhancing Cerebral Slow Waves in Sleeping Rats.

Polyherbal medicines are composed of multiple herbs and have traditionally been used in East Asian countries for the remedy of physiological symptoms. Although the effects of polyherbal formulations have been investigated at the molecular and behavioral levels, less is known about whether and how medicinal herbs affect the central nervous system in terms of neurophysiology. We introduced a novel blended herbal formulation that consisted of 35% linden, 21% mulberry, 20% lavandin, 20% butterfly pea, and 4% tulsi. After intraperitoneal administration of this formulation or saline, we simultaneously recorded epidural electrocorticograms (ECoGs) from the olfactory bulb (OB), primary somatosensory cortex (S1), and primary motor cortex (M1), along with electromyograms (EMGs) and electrocardiograms (ECGs), of rats exploring an open field arena. Using the EMGs and OB ECoGs, we segmented the behavioral states of rats into active awake, quiet awake, and sleeping states. Compared to saline, herbal medicine significantly shortened the total sleep time. Moreover, we converted the ECoG signal into a frequency domain using a fast Fourier transform (FFT) and calculated the powers at various ECoG oscillation frequencies. In the sleeping state, a slow component (0.5-3 Hz) of S1 ECoGs was significantly enhanced following the administration of the formulation, which suggests a region- and frequency-specific modulation of extracellular field oscillations by the polyherbal medicine.

Characteristic Components and Authenticity Evaluation of Rape, Acacia, and Linden Honey.

Honey fraud has an extensive global magnitude and impacts both honey price and beekeeper viability. This study aimed at investigating the characteristic phytochemicals of rape, acacia, and linden honey to verify honey authenticity. We discovered methyl syringate, phaseic acid, and lindenin (4-(2-hydroxypropan-2-yl) cyclohexa-1,3-diene-1-carboxylic acid) as particular or unique phytochemicals of rape, acacia, and linden honey. Methyl syringate and lindenin were the most abundant components in rape and linden honey; moreover, their average contents reached up to 10.44 and 21.25 mg/kg, respectively. The average content of phaseic acid was 0.63 mg/kg in acacia honey. To our knowledge, the presence of phaseic acid in honey is a novel finding. Furthermore, we established the HPLC fingerprints of three monofloral honeys. We offered assessment criteria and combined characteristic components with standard fingerprints to evaluate the authenticity of commercial rape, acacia, and linden honeys. For uncertain commercial honey samples, genuine pure honeys constituted nearly 70%. We differentiate the adulteration of acacia and linden honeys with low-price rape honey. Our results reveal that 10% of commercial honeys were pure syrups. Overall, we seem to propose a novel and reliable solution to assess the authenticity of monofloral honey.

Honey as Source of Nitrogen Compounds: Aromatic Amino Acids, Free Nucleosides and Their Derivatives.

The content of selected major nitrogen compounds including nucleosides and their derivatives was evaluated in 75 samples of seven varieties of honey (heather, buckwheat, black locust, goldenrod, canola, fir, linden) by targeted ultra-high performance liquid chromatography-diode array detector - high-resolution quadrupole time-of-flight mass spectrometry (UHPLC-DAD-QqTOF-MS) and determined by UHPLC-DAD. The honey samples contained nucleosides, nucleobases and their derivatives (adenine: 8.9 to 18.4 mg/kg, xanthine: 1.2 to 3.3 mg/kg, uridine: 17.5 to 51.2 mg/kg, guanosine: 2.0 to 4.1 mg/kg; mean amounts), aromatic amino acids (tyrosine: 7.8 to 263.9 mg/kg, phenylalanine: 9.5 to 64.1 mg/kg; mean amounts). The amounts of compounds significantly differed between some honey types. For example, canola honey contained a much lower amount of uridine (17.5 ± 3.9 mg/kg) than black locust where it was most abundant (51.2 ± 7.8 mg/kg). The presence of free nucleosides and nucleobases in different honey varieties is reported first time and supports previous findings on medicinal activities of honey reported in the literature as well as traditional therapy and may contribute for their explanation. This applies, e.g., to the topical application of honey in herpes infections, as well as its beneficial activity on cognitive functions as nootropic and neuroprotective, in neuralgia and is also important for the understanding of nutritional values of honey.

Comparison of Protein Precipitation Ability of Structurally Diverse Procyanidin-Rich Condensed Tannins in Two Buffer Systems.

The protein precipitation (PP) of bovine serum albumin (BSA), lysozyme (LYS), and alfalfa leaf protein (ALF) by four procyanidin-rich condensed tannin (CT) samples in both 2-[N-morpholino]ethanesulfonic acid (MES) and a modified Goering-Van Soest (GVS) buffer is described. Purified CT samples examined included Vitis vinifera seed (mean degree of polymerization [mDP] 4.1, 16.5% galloylated), Tilia sp. flowers (B-type linkages, mDP 5.9), Vaccinium macrocarpon berries (mDP 8.7, 31.7% A-type linkages). and Trifolium pratense flowers (B-type linkages, mDP 12.3) and were characterized by 2D NMR (>90% purity). In general, CTs precipitated ALF > LYS ≥ BSA. PP in GVS buffer was 1 to 2.25 times greater than that in MES buffer (25 °C). The GVS buffer system better reflects the results/conclusions from the literature on the impacts mDP, galloylation, and A-type linkages have on PP. Determinations of PP using the MES buffer at 37 °C indicated that some of these differences may be attributed to the temperature at which GVS buffer determinations are conducted. In vitro PP studies using the GVS buffer may offer better guidance when selecting CT-containing forages and amendments for ruminant feeding studies.

Secondary metabolites of Tilia tomentosa Moench inflorescences collected in Central Italy: chemotaxonomy relevance and phytochemical rationale of traditional use.

In this paper, the phytochemical analysis on the inflorescences (flowers and bracts) of a sample of Tilia tomentosa collected from an isolated population in Central Italy, was reported for the first time. Thirteen compounds (oleanolic acid, maslinic acid, apigenin, luteolin, kaempferol, quercetin, kaempferol-3-O-glucoside, quercetin-3-O-glucoside, rutin, tiliroside, ellagic acid, shikimic acid and quinic acid), belonging to several different classes of natural products, were identified on the basis of spectroscopic and spectrometric analysis. This sample was found to be mainly composed by flavonoids, followed by organic acids and pentacyclic triterpenes. The chemosystematic aspects of the identified components were also discussed, together with their pharmacologic relevance with respect to the traditional medicinal uses of this plant material.

A green, accurate and sensitive analytical method based on vortex assisted deep eutectic solvent-liquid phase microextraction for the determination of cobalt by slotted quartz tube flame atomic absorption spectrometry.

Preconcentration of cobalt was carried out with deep eutectic solvent based liquid phase microextraction (DES-LPME) for trace determination by a slotted quartz tube (SQT) attached flame atomic absorption spectrometry (FAAS) system. Choline chloride and phenol in a 1:2 M ratio was used as a green solvent to extract cobalt from the aqueous sample solution. Key parameters influencing the extraction efficiency of cobalt were examined and optimized. Under the conditions optimized, the linear dynamic range was found between 5.0 and 50 µg L-1, and the limits of detection and quantification (LOD and LOQ) were calculated as 2.0 and 6.6 µg L-1, respectively. The detection power of the conventional FAAS was improved upon by 67 folds using the optimized DES-LPME-SQT-FAAS method. The developed analytical method was successfully applied for the determination of cobalt in linden tea samples and the recovery results obtained for different spiked concentrations (20, 30 and 40 µg L-1) were remarkable (≈100%).

How does the content of nutrients in soil affect the health status of trees in city parks?

Trees have multi-aspect influence on the microclimate in urbanised areas. Therefore, it is important to investigate the biotic and abiotic factors affecting their health. The aim of the conducted study was to assess the chemical composition of soils and the nutritional status of lime and horse chestnut trees in selected sites and the influence of these factors on the condition and health of these tree species in urbanised areas. The research was conducted on selected trees (n = 643) growing in different parts of the city. The soils and plants were analysed for the content of macro- and microelements, sodium and heavy metals. A canonical variation analysis (CVA)-the canonical variant of Fisher's linear discriminant analysis (LDA) was used to construct the model. The CVA enabled the creation of 4 CCA models. The research showed that in general, the soil in all the sites of lime and horse chestnut trees was alkalised-at the same time it was characterised by low salinity. Despite the alkaline soil the statistical analysis showed a positive correlation between the content of manganese in the lime leaves and the deterioration of their health. In spite of that due to the satisfactory health status and condition of trees in most locations temporary guide values of nutrients were proposed for trees growing in urbanised areas. The following temporary guide values of nutrients were proposed for the horse chestnut trees (% d. m.): N 2.38%-4.71%, P 0.24%-0.46%, K 1.13%-2.31%, Ca 1.05%-2.12%, Mg 0.16%-0.42%, S 0.12%-0.23%; Fe 89.8-198.8, Zn 17.6-33.1, Cu 7.36-19.61 (mg kg-1 d. m.). The following temporary guide values were proposed for the small-leaved lime-trees (% d. m.): N 2.45%-3.22%, P 0.27%-0.42%, K 1.52%-2.86%, Ca 1.43%-2.02%, Mg 0.19%-0.35%, S 0.19%-0.25%; Fe 137.6-174.3, Zn 20.2-23.8, Cu 8.36-9.79 (mg kg-1 d. m.).

Hypoglycemic Activity of Tilia americana, Borago officinalis, Chenopodium nuttalliae, and Piper sanctum on Wistar Rats.

Diabetes mellitus (DM) is considered the epidemic of the 21st century. Traditional medicine uses plants to treat DM; many of these have hypoglycemic effects in both animal models and diabetic patients. Our objective was to evaluate the hypoglycemic activity of Tilia americana, Borago officinalis, Chenopodium nuttalliae, and Piper sanctum on diabetic rats. The methanolic extracts of the plants under study were obtained by Soxhlet extraction. Toxicity was evaluated on Artemia salina; the antioxidant potential was evaluated using the DPPH technique. Hypoglycemic capacity at doses of 250 and 500 mg/kg was tested on Wistar rats with diabetes induced by alloxan (120 mg/kg). The toxicity on A. salina was null for the extracts of B. officinalis and P. sanctum, moderate for T. americana, and highly toxic for C. nuttalliae. The relevant extract of T. americana var. mexicana showed antioxidant activity. Three plants of the studied plants showed hypoglycemic activity: Tilia Americana (p = 0.0142), Borago officinalis (p = 0.0112), and Piper sanctum (p = 0.0078); P. sanctum was the one that showed the greatest reduction in glucose levels at a lower dose.

Compound-specific δ15N values express differences in amino acid metabolism in plants of varying lignin content.

Amino acid δ15N values of foliage of various plant taxa, grown at the experimental farm stations of North Wyke, UK and Bad Lauchstädt, Germany were determined by GC-C-IRMS. The difference between δ15N values of glutamate (Glx) and phenylalanine (Phe) were found to differ significantly between woody and herbaceous plants, with mean Δ15NGlx-Phe (i.e. δ15NPhe - δ15NGlx) values of -9.3 ±â€¯1.6‰ and -5.8 ±â€¯2.1‰, respectively. These differences in values are hypothesised to be due to the involvement of Phe in the phenylpropanoid pathway, by which lignin and other phenolic secondary metabolites are produced, leading to isotopic fractionation and enrichment of the remaining Phe pool available for protein biosynthesis. This results in the more negative Δ15NGlx-Phe values observed in woody plants relative to herbaceous plants, as the former are assumed to produce more lignin. To test this assumption, plant leaf tissue lignin concentrations were estimated by solid state 13C cross-polarisation, magic-angle-spinning (CPMAS) NMR spectroscopy for a subset of plants, which showed that tree foliage has a higher concentration of lignin (12.6 wt%) than herbaceous foliage (6.3 wt%). The correlation of lignin concentration with Δ15NGlx-Phe values demonstrates that the difference in these values with plant type is indeed due to differential production of lignin. The ability to estimate the lignin content of plants from amino acid δ15N values will, to give one example, allow refinement of estimates of herbivore diet in present and past ecosystems, enabling more accurate environmental niche modelling.

The relationship between physiological and mechanical properties of Acer platanoides L. and Tilia cordata Mill. leaves and their seasonal senescence.

The seasonal senescence of leaves in the phenological cycle coincides with the change of their strength properties which determine resistance to environmental conditions and the efficiency of the photosynthesis process. That affects the development, growth and condition of the plant. Therefore, the aim of this paper was to observe and compare the results of strength tests performed on the leaves of two species of trees popular in Poland - lime and maple. As well as chlorophyll fluorescence and photosynthetic pigments content in the context of the changes occurring during the entire leaf life cycle. Obtained results showed that the strength properties of the tested leaves reached the minimum values in spring and the maximum in the summer similarly to the leaf greenness index. Whereas the fluorescence increased which the seasonal senescence in opposition to the photosynthesis efficiency of the leaves. Collected data revealed that strength parameters and photosynthetic pigment content were significantly higher for maple leaves than for lime leaves. Studies showed differences between physiological and mechanical properties of the leaves of two trees species, even if they grew under the same environmental conditions. It is concluded from the results that phenotype and physical parameters of leaves are related to seasonal senescence.

Magnetic and SEM-EDS analyses of Tilia cordata leaves and PM10 filters as a complementary source of information on polluted air: Results from the city of Parma (Northern Italy).

In this work, both PM10 filters and leaves have been collected, on a daily basis, over a period of five months and compared systematically. Filters were taken from an air-quality monitoring station and leaves from two Tilia cordata trees, both located near the railway station of Parma. SEM-EDS analysis on the surface and across the leaves shows that magnetic particles are almost entirely made of magnetite, and that they are found invariably on the leaves surface. The saturation isothermal magnetic remanence (SIRM) shows that for both filters and leaves the magnetic fraction mainly consists of a low coercivity, magnetite-like phase. The magnetic signals of filter and leaves and atmospheric PM concentrations are compared. The correlation is better for filters, mostly with parameters related to vehicular pollution, and improved for both filters and leaves once data were averaged on a 10 days basis. Filters and leaves equally show an increase in magnetic signal during the fall-winter period together with PM10 content. The comparison between leaves and filters shows that: 1) leaves give a qualitative picture, and in our case they could be used as environmental proxies after averaging the results over multiple days; 2) the correlation with PM10 is weaker, indicating that there is a PM10 contribution from non-magnetic particles, like calcite and clay minerals, pollen and spores; 3) multidomain particles contribution from filters indicates a strong relation with vehicular polluters, suggesting the important role of larger particles; 4) magnetization from leaves and filters are weakly related, due to the different sampling lapse.

Quantitative and Discriminative Evaluation of Contents of Phenolic and Flavonoid and Antioxidant Competence for Chinese Honeys from Different Botanical Origins.

Phenolics and flavonoids in honey are considered as the main phytonutrients which not only act as natural antioxidants, but can also be used as floral markers for honey identification. In this study, the chemical profiles of phenolics and flavonoids, antioxidant competences including total phenolic content, DPPH and ABTS assays and discrimination using chemometric analysis of various Chinese monofloral honeys from six botanical origins (acacia, Vitex, linden, rapeseed, Astragalus and Codonopsis) were examined. A reproducible and sensitive ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was optimized and validated for the simultaneous determination of 38 phenolics, flavonoids and abscisic acid in honey. Formononetin, ononin, calycosin and calycosin-7-O-ß-d-glucoside were identified and quantified in honeys for the first time. Principal component analysis (PCA) showed obvious differences among the honey samples in three-dimensional space accounting for 72.63% of the total variance. Hierarchical cluster analysis (HCA) also revealed that the botanical origins of honey samples correlated with their phenolic and flavonoid contents. Partial least squares-discriminant analysis (PLS-DA) classification was performed to derive a model with high prediction ability. Orthogonal partial least squares-discriminant analysis (OPLS-DA) model was employed to identify markers specific to a particular honey type. The results indicated that Chinese honeys contained various and discriminative phenolics and flavonoids, as well as antioxidant competence from different botanical origins, which was an alternative approach to honey identification and nutritional evaluation.

The influence of procyanidins isolated from small-leaved lime flowers (Tilia cordata Mill.) on human neutrophils.

Linden flower is a wildly used plant material among patients in the treatment of common cold symptoms and mucosa inflammations. However, the structure and bioactivity of flavan-3-ol derivatives present in infusions from flowers of Tilia cordata have not been studied so far. The aim of current study was to isolate and identify main procyanidins present in the flowers of small-leaved lime and to evaluate their influence on the inflammatory response of human neutrophils ex vivo. The chemical structure of isolated compounds was established by 1D and 2D NMR experiments. The bioactivity of obtained compounds was tested in human neutrophils model. Cytotoxicity and influence of compounds on apoptosis was established by flow cytometry. The levels of produced cytokines were established by ELISA after stimulation with lipopolysaccharide (LPS). The inhibition of the production of reactive oxygen species was checked by luminol-dependent chemiluminescence method after N-formylmethionyl-leucyl-phenylalanine (f-MLP) induction. The phytochemical work resulted in the isolation of 10 compounds. Compounds were identified as oligomeric procyanidins and their precursor epicatechin. The potential anti-inflammatory activity of compounds was evaluated in the concentration range 5-20 µM. All compounds were able to decrease the production of ROS from f-MLP-stimulated neutrophils. Most of compounds were able to inhibit the LPS-induced release of IL-8. Some trimeric and tetrameric derivatives were also able to decrease the production of MIP-1ß. Obtained results partially support the traditional usage of infusion from lime flowers in the treatment of symptoms of inflammation and irritation of mucosa in common cold, pharyngitis and tonsillitis.