Linden Honey Research Articles

Preliminary study on the authenticity of acacia, multifloral and linden honey from Cluj County.

Honey samples from two different types of locations from Cluj county were subjected to this study: the beekeeping store APICO LA and the main free markets in the county. Seventeen honey samples representing three different types of Romanian honey: acacia, multifloral and linden honey for the main physical-chemical par ameters were analyzed. Water and hidroxy- methilfurfural (HMF) content, together with sugar s pectrum were analyzed into the APHIS Laboratory, USAMV Cluj. All determined parameters were situated within the limits established by Romanian and International Standards. For water content, the values were found between 16.0-19.9% for all honey types. HMF parameter was situated bet ween 1.49-29.4%, indicating freshness for some honey samples and some unsuitable storage conditions for other honey samples. The main sugars in honey are fructose and glucose. Their individual va lues as well as their sum or ratio, places all samp les in the characteristics of the respective honey type . Turanose, maltose, isomaltose and erlose are also present in different amounts in almost all honeys. The samples were authentic and having the declared botanical origin in terms of the physical-chemical analysis.

Iš baltų etimologijos

FROM BALTIC ETYMOLOGY (1. “SIEVE” AND “PLEIADES”; 2. LITH. Medv ė́ galis ; 3. LITH. ŽEM. Tvẽrai ) Summary 1. The form pr. E (346) baytan “sieve” should be corrected to Pr. (E) * saytan “id.” = Pr. * saitan “id.”, while this is derived from balt. * seitan “id.” (neutr.), which was not only “sieve”, but also “Pleiades” (an astronomical term). Later on the following formed: a) For Eastern Balts next to the form * seitan (neutr.) “sieve; Pleiades” its suffix derivative * Seitīna- “Pleiades” (seems to be neutr.) and b) for Western Balts next to the form * seitan “sieve; Pleiades” suffix derivative * Seitāran “Pleiades” (neutr.); the last being shown by its form (E 6) * Paytoran „id.“, should be corrected to * Saytoran = pr. * Paitāran „id.“ (neutr.), which probably derives from Western Balt. * Seitāran „id.“ (neutr.). The word is Baltic, i.e. Balt.-Sl. * seitan “sieve” – the derivative of the suffix * -ta- is from the presentic stem from the old Balt.–Sl. verb * sē-ti “to sift, sieve”. 2. The name Medvėgalis (the ía- stem), which is the name of a large hilly area with small rivers fed by underground well, is a composition with a second component of -galīs from galas , meaning “corner, place ” . The component Medvē- , which should not be linked with Žem. mẽdė “forest ” , the little river’s name supposed by Cur. *Med(u)vē , flowing through a Curonian sacrificial place (a holy site). The gender of *Med(u)vē (up.) from the older Cur., *Med(u)vā is the suffix’s *-(u)vā- derivative from subst. Curonian (Balt.) *medu “honey ” (neutr.). Such an etymology of the river’s name is supported by the river’s holyness (because of the sacrificial place) and especially the fact, that its water was clean because of the currents (where it flowed along the banks) and was clear like fresh linden honey (it seems that for the Balts, honey was holy). 3. The name of the old Samogitian settlement called Tvẽrai , mentioned numerous times in the writings of the Teutonic Order dating from the 13th-14th century, first of all arose in the form Rus. (1251) Твиреметь ( Твиременть ), the origin of which is unclear. Now it has become clear, that this Russian form reflects the Lith. (Žem.) composition * Tveramedīs “Forest of Tverai ” ( ía- kamienį), which is: * Tvera- (= sing. * tveras “enclosure ” ) + * -medīs (< Žem. mẽdė “forest ” ). Next to the form Lith. (Žem.) * tveras “enclosure ” would have been from Lith. (Žem.) * tverta- “id. ” . Both synonyms are from Lith. (Žem.) * tvaras “id. ” resp. * tvarta- “id. ” – a suffixed derivative from the verb Cur. (Balt.) * tvar- “to enclose ” .

Antioxidant activity of three different Serbian floral honeys

In this study, three Serbian honey samples (Acacia, Linden and "Homoljski med") were analyzed to determine their total phenolic, flavonoid and antioxidant content, as well as their in vitro antioxidant activity. The antioxidant activity of honeys was examined by different tests, including the reducing power and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. In addition, correlations between the antioxidant activity and total phenolic, as well as flavonoid content were also sought. The highest content of total phenolics (27.44 mg/100 g), flavonoids (9.78 mg/100 g), reducing power and DPPH free radical scavenging activity were obtained in the case of Linden honey. The EC50 values of the Linden honey, determined based on the reducing power and DPPH radical scavenging activity, were 24.17 mg/ml and 51.34 mg/ml, respectively. Also, the antioxidant content was highest for Linden honey, and it valued 5.45 mg QEAC/100 g (expressed as mg of quercetin equivalent antioxidant content - QEAC per 100 g of honey) and 7.82 mg AEAC/100 g (expressed as mg of ascorbic acid equivalent antioxidant content - AEAC per 100 g of honey). Also, a linear correlation was observed between the antioxidant activity and total phenolics, as well as total flavonoids.

Antioxidative, antibrowning and antibacterial activities of sixteen floral honeys

Commonly consumed honeys from sixteen different single floral sources were analyzed for their in vitro antioxidant capacities by several methods including DPPH, ABTS, FRAP, SASR and MDA assays. The total polyphenol contents varied among the tested honeys and were highly correlated to their antioxidant capacity values. The antioxidant capacity of Chinese milk vetch flower honeys was significantly higher than those of other flower honeys. All honeys tested were active in inhibiting the browning of apple homogenate and linden honey displayed the highest inhibition rate as 85%. When the antimicrobial activity of the investigated honeys was screened using Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli), clover honey exhibited the strongest antibacterial activity as 2.2 mg mL(-1) kanamycin equivalent inhibition.

Comparison of quality parameters of producers' and commercial honeys

Honey is our essential food since ancient times. In Hungary about 25 000 tons of honey are produced each year, and most of the product (80%) is exported. Hungarian honeys have excellent quality but because of scandals of honey adulteration the interest and recognition may decrease. Therefore we must elaborate a method with which the establishment of adulteration is simple and cheap. In this study we concentrate on simple quality parameters which inspection is not elaborate. These parameters for example sugar- and moisture contains, proline content, electricalconductivity, element content, pH, HMF content, degree of acidity. We examined these parameters in producers’ and commercial samples. We succeed fund parameters which characteristic of one type of honey thus we have possibility identify of honey type. For example the proline content was very low in the producers’ linden honey (mean 126 mg/kg). This value is lower than the regulation, but in case of commercial linden honey this parameter is higher than regulation. According to electrical conductivity and Potassium content is provable the type of linden honey.

Quorum sensing inhibitory and antimicrobial activities of honeys and the relationship with individual phenolics

Quorum sensing (QS) inhibitory activity of 29 unifloral honeys was evaluated using the bacterial model Cromobacterium violaceum. The tested honeys were able to inhibit the production of acyl-homoserine lactones (AHLs) produced by C. violaceum at 0.1 g/ml. However, chestnut and linden honey samples showed the highest inhibitory activity, while orange and rosemary were less effective in inhibiting QS. When honey samples from the same floral origin obtained from different geographical regions were compared, they showed similar QS inhibitory activity. Thus, one of the factors which influence the inhibitory activity could be derived from the floral origin, independently of the geographic location. It was observed that unifloral honey samples showed “non-peroxide” anti-QS activity, which was not linearly correlated with total and individual phenolic compounds. The obtained results showed that the preservative properties of honey could be due to both the antimicrobial properties and the QS inhibitory capacity.

Antibacterial Effect of Honey on Staphylococci Species Isolated

The inhibitory and bactericide effect of 4 sort of honey (forest honey, poly-flower honey, linden tree honey and acacia honey) on some staphylococci species (Staphylococcus aureus 4 strains, Staphylococcus intermedius, Staphylococcus xilosus, Staphylococcus hominis, Staphylococcus chromogenes and Staphylococcus sciuri) isolated from humans and animals was tested in this experiment. For the tests the following methods were used: difusimethrical method in Mueller-Hinton agar, dilution methods in liquid medium in order to determinate M.I.C. and M.B.C. Species S. aureus, S. xilosus and S. intermedius were sensitive to all the honey types tested, the highest inhibitory diameter areas (30-40 mm) being obtained for forest honey followed by poly-flower honey (maximum 30 mm). S. hominis, S. chromogenes and S. sciuri were not as sensitive to honey activity, obtaining reduced inhibition areas. Staphylococci species used in the experiment were sensitive to ampicillin and ceftiofur but resistant to penicillin, enrofloxacin, tetraciclin, gentamicin and kanamicyn. The results obtained are sugesting that forest honey and poly-flower honey honey had good antibacterial effect on the species tested, similar to the best antibiotics

The evaluation of microbiological quality of some bee honey sorts.

Due to its particular composition, honey has the ability of inhibiting and even destroying microorganisms. However, certain types of micro-organisms persist in honey, usually in latent condition, and some species of yeasts, due to their pronounced osmophilic trait, can multiply and cause fermentation of the product, making him unfit for human consumption. Research has been conducted in 2007 and 2008, being prelevated and examined a total number of 552 samples from 5 sorts (locust tree honey, linden tree honey, sunflower honey, rape honey and polifloral honey). Laboratory analyses have endorsed the determination of the total number of yeasts and moulds, using the colonies counting technique (CFU/g). It was found that the examined honey samples had a minimal contamination, in several ones being detected the presence of pathogenic conditioned bacteria or pathogenic bacteria, and some others presented an yeasts and moulds level higher than 100 CFU/g, the sorts with the highest number of fungi being the sunflower honey and the rape honey

Erythromycin residue in honey from the Southern Marmara region of Turkey

Honey samples, collected from the Southern Marmara region of Turkey, were analysed for erythromycin residues by liquid chromatography–mass spectrometry using electrospray ionization in the positive ion mode (LC–ESI–MS). Fifty samples, comprising chestnut, pine, linden and multi-flower honeys, were collected directly from hives and analyzed. The limit of detection and quantification were 6 and 20 ng g−1, respectively, and recovery ranged from 85 to 89%. Four of the honey samples (8%) were found to be contaminated with erythromycin residues at concentrations ranging from 50 to 1776 ng g−1. An erythromycin-fortified cake feeding assay was also performed in a defined hive to test the transfer of erythromycin residue to the honey matrix. In this test hive, the residue level in the honey, 3 months after dosing, was approximately 28 ng g−1.

A solid-phase extraction procedure coupled to 1H NMR, with chemometric analysis, to seek reliable markers of the botanical origin of honey

The aim of this work was to establish an analytical method for identifying the botanical origin of honey, as an alternative to conventional melissopalynological, organoleptic and instrumental methods (gas-chromatography coupled to mass spectrometry (GC–MS), high-performance liquid chromatography HPLC). The procedure is based on the 1H nuclear magnetic resonance (NMR) profile coupled, when necessary, with electrospray ionisation-mass spectrometry (ESI-MS) and two-dimensional NMR analyses of solid-phase extraction (SPE)-purified honey samples, followed by chemometric analyses. Extracts of 44 commercial Italian honeys from 20 different botanical sources were analyzed. Honeydew, chestnut and linden honeys showed constant, specific, well-resolved resonances, suitable for use as markers of origin. Honeydew honey contained the typical resonances of an aliphatic component, very likely deriving from the plant phloem sap or excreted into it by sap-sucking aphids. Chestnut honey contained the typical signals of kynurenic acid and some structurally related metabolite. In linden honey the 1H NMR profile gave strong signals attributable to the mono-terpene derivative cyclohexa-1,3-diene-1-carboxylic acid (CDCA) and to its 1- O-β-gentiobiosyl ester (CDCA-GBE). These markers were not detectable in the other honeys, except for the less common nectar honey from rosa mosqueta. We compared and analyzed the data by multivariate techniques. Principal component analysis found different clusters of honeys based on the presence of these specific markers. The results, although obviously only preliminary, suggest that the 1H NMR profile (with HPLC–MS analysis when necessary) can be used as a reference framework for identifying the botanical origin of honey.

From Linden Flower to Linden Honey. Part 2

The presence of two unusual, recently identified terpene acids, i.e., 4-(1-hydroxy-1-methylethyl)cyclohexa-1,3-diene-1-carboxylic acid (1) and 4-(1-methylethenyl)cyclohexa-1,3-diene-1-carboxylic acid (2), was now also confirmed in (Swiss) linden honey, after solid-phase extraction and HPLC purification. NMR Spectroscopy, in combination with UPLC/MS analysis, showed the presence of several glycosides of 1, which accounted for ca. 0.6 weight-% of the honey, as quantified by UPLC-UV. The major 'glycoside' of 1, compound 5, could be isolated and identified by 2D-NMR experiments as the corresponding beta-gentiobiosyl ester (rather than the classical compound with a glycosidic bond between an aglycone OH group and the sugar). The same diglycosides found in linden honey were also detected in linden nectar; also, chestnut and fir honeys contained these glycosides in minor quantities, but not colza, acacia, or dandelion honeys (Table 2).

From the Linden Flower to Linden Honey – Volatile Constituents of Linden Nectar, the Extract of Bee‐Stomach and Ripe Honey

Honey is produced by honeybees (Apis mellifera), which collect nectar from flowers, digest it in their bodies, and deposit it in honeycombs, where it develops into ripe honey. We studied the evolution of the volatile constituents from the nectar of linden blossoms (Tilia cordata) to honey via the 'intermediate' honeybee. The sampling of the contents of the honey stomach or honey sack of the bee is unique. Extracts were prepared from nectar, from the liquid of the honey stomach, and from ripe honey. The chemistry is extremely complex, and compounds spanning from monoterpenes (hydrocarbons, ethers, aldehydes, acids, and bifunctional derivatives), isoprenoids, aromatic compounds (phenylpropanoids, phenols), and products degraded from fatty acids to alkaloids, were identified. Some compounds definitely stem from the plants, whereas other interesting constituents can be attributed to animal origin. Two derivatives of decanoic acid, 9-oxodec-2-enoic acid (12) and 9-hydroxydec-2-enoic acid, identified in the honey are known to be constituents of the so-called 'Queen's pheromone'. Two metabolites of these acids were identified in the extract of the honey stomach: 8-oxononanal (10), a new natural product, and 8-oxononanol (11). There structures were confirmed by synthesis. Nectar and honey stomach contain many aldehydes, which, due to the highly oxidative atmosphere in the honeycomb, are found as corresponding acids in the honey. Two acids were newly identified as 4-isopropenylcyclohexa-1,3-diene-1-carboxylic acid (14) and 4-(1-hydroxy-1-methylethyl)-cyclohexa-1,3-diene-1-carboxylic acid (15).

ChemInform Abstract: Determination of the Chemical Structure of Linden Ether

The chemical structure of the novel monoterpene 1, named ‘linden ether’ and isolated from linden honey and the blossoms of lime tree (Tilia cordata), was studied by two-dimensional NMR spectroscopy, by high-resolution MS as well as by hydrogenation experiments and by GC on a chiral phase. Thus, linden ether was identified as a racemic mixture, i.e. (7aRS)-2, 4, 5, 7a-tetrahydro-3, 6-dimethylbenzofuran.

Determination of the Chemical Structure of Linden Ether

AbstractThe chemical structure of the novel monoterpene 1, named ‘linden ether’ and isolated from linden honey and the blossoms of lime tree (Tilia cordata), was studied by two‐dimensional NMR spectroscopy, by high‐resolution MS as well as by hydrogenation experiments and by GC on a chiral phase. Thus, linden ether was identified as a racemic mixture, i.e. (7aRS)‐2, 4, 5, 7a‐tetrahydro‐3, 6‐dimethylbenzofuran.

Occurrence of trehalulose, 1-O-.ALPHA.-D-glucopyranosyl. D-fructose, in nectar honey.

From a Japanese linden honey sample, trehalulose, 1-O-α-D-glucopyranosyl-D-fructose, was isolated by gel filtration chromatography, ion exchange chromatography and preparative HPLC, and was finally identified by TLC and 13C-NMR. Occurrence of trehalulose was confirmed in 9 nectar honey samples derived from 7 floral sources in Japan. Trehalulose contents of the honey samples ranged from 0.5 to 2.5% of total solid.

Intensive neutral odourants of linden honey Differences from honeys of other botanical origin

Aroma extract dilution analysis of linden honey volatiles resulted in 21 odour compounds having high factors of dilution (FD); 18 of these compounds were identified as 1-hexen-3-one, 2-acetyl-1 -pyrroline, dimethyl trisulphide, methional, phenylacetaldehyde, 2-phenylethanol, linalool, p-cresol, 3,9-epoxy-lpmenthene, 4-methylacetophenone, 3,9-epoxy-1,4(8)-p-menthadiene (linden ether), 1,3 p-menthadien-7-al, p-anisaldehyde, 4vinylguaiacol, (E)-p-damascenone, eugenol, vanillin andcis-rose oxide. Linden ether andcis-rose oxide, which were also found in an extract obtained from the blossoms of the lime tree (Tifa cordata), were absent in honeys of other botanical origin. These two odourants and the odourlesstrans-limonene-1,2-diol are proposed as indicators for linden honey. The odour thresholds (in air) of the 18 aroma compounds are reported.