Rapid determination of minority organic acids in honey by high-performance liquid chromatography

Quantification of two derivatives of malic acid first-time discovered in coffee: Influence of postharvest processing method

This study quantified, for the first time, 2-isopropylmalic and 3-isopropylmalic acids, in green, roasted and espresso coffee by UHPLC-MS/MS. Moreover, it reports the influence of postharvest processing methods (natural, washed and honey) on their content. New extraction techniques were developed and validated from three coffee matrices (green, roasted and espresso). Honey coffee exhibited levels substantially higher of 2-isopropylmalic acid than those processed by natural and washed methods (p < 0.05). Specifically, 2-isopropylmalic acid levels in honey green, roasted and espresso coffee samples were 48.24 ± 7.31 ng/g, 168.8 ± 10.88 ng/g and 177.5 ± 9.49 ng/g, respectively. This research highlights the significant impact of processing methods on the chemical profile of coffee and introduces 2-isopropylmalic and 3-isopropylmalic acids as potential quality indicators. Moreover, it suggests that the fermentation stage during processing may play a crucial role in their formation, laying the foundation for optimizing coffee processing to enhance quality.

Low Heating Effects on The Total Microbial Activity and Physico-Chemical Properties of Stingless Bee (Heterotrigona itama) Honey

The high moisture content of stingless bee honey (SBH) is a worrisome problem and heat treatment is used to reduce the moisture and maintain the honey’s quality by destroying the microorganisms that affect the physico-chemical properties of honey during storage. Low heat treatment (45 °C) for 0, 30, 60, 90, and 120 min were conducted to determine the total microbial activity using fluorescein diacetate hydrolysis (FDA). The total microbial population that subsequently affected the physico-chemical properties was also analyzed. The total microbial activities of SBH were significantly reduced after thermal treatment at 45 °C for 90 min (63.76 µg FDA/g/h) and 120 min (62.43 µg FDA/g/h) compared with control (67.127 µg FDA/g/h). Also, the moisture content, electrical conductivity (EC), pH, and free acidity of the heat-treated SBH at all durations were significantly reduced compared with the control. The total microbial activity was detected as significantly correlated to bacterial and fungal populations, moisture content, EC, pH, and free acidity of low heat-treated SBH. Low heat treatment at 45 °C for 120 min was efficient to reduce the total microbial activity, and total acidity, and increasing the pH of SBH. Prolonging the heating duration is suggested to further reduce the water content, and total microbial activity and further increase the shelf life of SBH.

Identification of the botanical origins of honey based on nanoliter electrospray ionization mass spectrometry

The botanical origins of honey are important for the quality control and commercialization of honey. In this research, we established a nanoliter electrospray ionization mass spectrometry (Nano-ESI-MS) method to identify Castanopsis honey (CH), Eurya honey (EH), Dendropanax dentiger honey (DH), and Triadica cochinchinensis honey (TH). In total, 38 compounds were identified based on the collision-induced dissociation experiments by Nano-ESI-MS with 16 differential compounds and 7 quantified as potential differential markers. These four types of honey were distinguished from each other by their mass spectrometry data combined with multivariate analysis with three out of the 7 differential markers, i.e., phenethylamine, tricoumaroyl spermidine, and (+/-)-abscisic acid, identified as potential markers for CH, EH, and DH, respectively. Both the qualitative and quantitative results derived from Nano-ESI-MS were further verified by UPLC-Q/TOF-MS. Our studies provided the significant potential of the Nano-ESI-MS method in the identification of the botanical origins of different kinds of honey.

Establishment and application of quantitative method for 22 organic acids in honey based on SPE-GC–MS

Honey, a natural healthy liquid bee product, is rich in amino acids, vitamins, and other essential nutrients. Different origin honeys also varied in organic acids. The objective of this study is to establish an efficient solid-phase extraction-gas chromatography–mass spectrometry (SPE-GC–MS) method to eliminate interference of sugar and other impurities for accurately estimating 22 organic acids in honey by optimizing extraction, purification, derivatization, and gas chromatography–mass spectrometry (GC–MS) analytical conditions. After being extracted, purified and derivatized, organic acids in honey were qualified and quantified by GC–MS. This method was evaluated experimentally, and the results showed that, within a certain concentration range, the standard curve linear relationship was satisfactory (R2 > 0.9942), and the target organic acid recovery rate was 86.74% ~ 118.68%. Besides, precision (relative standard deviation, RSD = 2.98% ~ 13.42%), detection limit (LOD = 0.002 ~ 0.2 mg kg−1), and quantification limit (LOQ = 0.008 ~ 0.5 mg kg−1) met the target requirements. Also, based on this analytical method, the organic acids in five types of honey (acacia, jujube, vitex, canola and linden honey) were estimated. Notably, they all contained 22 different kinds of organic acids, and significant differences (p < 0.05) in the organic acid content and composition among different honey varieties were observed. PCA analysis showed that the five honeys could be differentiated based on the content of 22 organic acids.

Evaluating the Physicochemical Properties of Some Kosovo’s and Imported Honey Samples

This study evaluated the physicochemical properties (moisture, pH, electrical conductivity, free acidity, hydroxymethylfurfural (HMF), proteins, insoluble solids, and ash) of 45 Kosovo’s and imported honey samples, using methods provided by national and international standards. The moisture values of all honey samples analyzed were below 20%. The free acidity was above 50.0 meq kg−1 in 14 out of 33 samples (42%) collected in Kosovo, while 2 out of 12 imported honey samples (16.7%) showed higher values than 50 meq kg−1. In this study, 7 out of 33 honey samples (21%) from Kosovo and one out of 12 honey samples from imports had soluble solids content below 80 °Brix. In terms of HMF, 5 out of 33 Kosovo honey samples (15%) and 4 out of 12 imported honey samples (33%) exceeded 40 mg/kg, which is the maximum content of HMF set in standards. The values of some physicochemical parameters (free acidity, HMF, and soluble solids) of local and imported honey samples are not within the quality limits set in legislation. Further studies are needed to evaluate the properties of fresh honey produced in Kosovo and the stability of honey during prolonged storage.

Optical spectroscopy methods combined with multivariate statistical analysis for the classification of Cretan thyme, multi-floral and honeydew honey

BACKGROUND

The botanical origin of honey attracts both commercial and research interest. Consumers' preferences and medicinal uses of particular honey types drive the demand for the determination of their authenticity with regard to their botanical origin. This study presents the discrimination of thyme, multi-floral. and honeydew honeys by Fourier-transform infrared (FTIR) and ultraviolet (UV) absorption spectroscopy combined with multivariate statistical analysis. UV absorption spectroscopy was applied without any dilution of the sample using a custom-made cuvette. FTIR and UV absorption spectroscopic data were processed by means of the orthogonal partial least squares discriminant analysis.

RESULTS

The optimal classification of floral and honeydew honeys was accomplished with UV spectroscopy with a successful estimation of 92.65% for floral honey and 91.30% for honeydew honey. The discrimination of thyme versus the multi-floral honey was best achieved with FTIR, with a correct classification of 95.56% and 100% for multi-floral and thyme honey respectively. Furthermore, our findings revealed the region of 2400-4000 cm^-1 of the FTIR spectra as the most significant for this discrimination.

CONCLUSION

This work demonstrates that optical spectroscopic techniques in combination with multivariate statistical analysis can be a rapid, low-cost, easy-to-use approach for the determination of the botanical origin of honey without sample pretreatment. © 2021 Society of Chemical Industry.

Aliphatic organic acids as promising authenticity markers of bracatinga honeydew honey

This study aimed to differentiate bracatinga (Mimosa scabrella Bentham) honeydew honey (BHH) from blossom honeys and BHH intentionally adulterated, all of them from three harvests, associating data of aliphatic organic acids (AOA) determined by capillary electrophoresis and chemometric analyses. The profile and concentration of AOA in pure BHH were similar between harvests, but distinct from blossom honeys. Succinic, glycolic, glutaric, malic, acetic, gluconic, and lactic acids were responsible for the differentiation between these two types of honey since they were the dominant variables (r > 0.80) in the principal component analysis. Based on this, the classification and regression trees method was used to develop a classification model considering these AOA. The proposed method needed only six of these AOA and adequately classified all blossom honeys and almost all pure and adulterated BHH. Therefore, the proposed model proved to be promising and reliable for verifying authenticity and fraud detection in BHH.

Validation and Application of a Derivatization-Free RP-HPLC-DAD Method for the Determination of Low Molecular Weight Salivary Metabolites

Saliva is an interesting, non-conventional, valuable diagnostic fluid. It can be collected using standardized sampling device; thus, its sampling is easy and non-invasive, it contains a variety of organic metabolites that reflect blood composition. The aim of this study was to validate a user-friendly method for the simultaneous determination of low molecular weight metabolites in saliva. We have optimized and validated a high throughput, direct, low-cost reversed phase liquid chromatographic method with diode array detection method without any pre- or post-column derivatization. We indexed salivary biomolecules in 35 whole non-stimulated saliva samples collected in 8 individuals in different days, including organic acids and amino acids and other carbonyl compounds. Among these, 16 whole saliva samples were collected by a single individual over three weeks before, during and after treatment with antibiotic in order to investigate the dynamics of metabolites. The concentrations of the metabolites were compared with the literature data. The multianalyte method here proposed requires a minimal sample handling and it is cost-effectiveness as it makes possible to analyze a high number of samples with basic instrumentation. The identification and quantitation of salivary metabolites may allow the definition of potential biomarkers for non-invasive "personal monitoring" during drug treatments, work out, or life habits over time.

Eucalyptus honey: Quality parameters, chemical composition and health-promoting properties

Eucalyptus honey is an important unifloral honey commercialized worldwide and much desired by consumers due to the medicinal properties attributed to it because of the plant from which it is produced. In general, eucalyptus honey has been classified as being rich in pollen grains from the eucalyptus tree as well as having physicochemical characteristics that, in a way, have made it stand out from other honeys. Similar to other types of honey, eucalyptus honey can suffer contaminations and adulterations that compromise its quality, safety and authenticity. Thus, detailed knowledge of the composition and properties of this monofloral honeys is of great importance. With this background, the aim of this review is to present and discuss recent data regarding the physicochemical characteristics, chemical and health-promoting properties of eucalyptus honey as well as microbial contamination, authenticity, processing and adulteration.

Antioxidant Activity, Total Phenolic Content, Individual Phenolics and Physicochemical Parameters Suitability for Romanian Honey Authentication

The present study aimed to evaluate the physicochemical characteristics of honey (raspberry, mint, rape, sunflower, thyme and polyfloral) produced in Romania. The honey samples were from the 2017 to 2018 harvest and were subjected to melissopalynological analysis, alongside the determination of the following physicochemical parameters: moisture content, pH, free acidity, electrical conductivity (EC), hydroxymethylfurfural (HMF) content, color, total polyphenols content (TPC), flavonoids content (FC), DPPH radical scavenging activity, phenolic acids, flavonols, sugars and organic acids in order to evaluate the usefulness of this parameters for the classification of honey according to botanical origin. The results of the melissopalynological analysis revealed that five types of honey samples had a percentage of pollen grains above the minimum of 45%, which was required in order to classify the samples as monofloral honey. The total polyphenols content reached the maximum value in the case of dark honey such as mint honey, followed by raspberry, thyme and polifloral honey. Fructose, glucose, maltose, sucrose, turanose, trehalose, melesitose, and raffinose were identified and quantified in all samples. Gluconic acid was the main organic acid in the composition of all honey samples. Principal component analysis (PCA) confirmed the possibility of the botanical authentication of honey based on these physicochemical parameters.

Pathway of 5-hydroxymethyl-2-furaldehyde formation in honey

5-hydroxymethyl-2-furaldehyde (5-HMF) is an important substance that affect quality of honey and shows toxicity for humans and honey bees. The pathway of 5-HMF formation in honey is still unknown. In this study, we tested the effect of thermal treatment (at 90 °C for 4 h) on the formulation of 5-HMF formulation in rapeseed with varied honey composition. 5-HMF content of honey increased at higher water content, Ca²⁺ and Mg²⁺ content and lower pH. However, the formation of 5-HMF was not significantly influenced by glucose, fructose, Na⁺, or K⁺ contents. Furthermore, different content of proline, the most abundant amino acid in honey (a substance in Maillard reaction), had no effect on 5-HMF formation. Free acids in honey can catalyze fructose and glucose to form 5-HMF. These results suggest that dehydration of glucose or fructose, instead of the Maillard reaction, is the main pathway of 5-HMF formation in honey. This study gives new insights for the mechanisms of 5-HMF formation and provides method for reducing 5-HMF formation during honey processing.

Quality characterization and effect of sonication time on bioactive properties of honey from North East India

The North-Eastern region of India is known for its rich flora and has great potential for honey production. Honey samples collected from local markets of different regions of North-East India viz. Shillong, Sohra, Mawsynram, Jorhat and Tezpur were analyzed for physicochemical properties, bioactivity and mineral content. Effect of sonication time on the bioactive properties of honey was determined. All the honey samples had good bioactive properties and high content of potassium, sodium, calcium and iron. The Jorhat sample had the highest phenolic content (296.68 ± 2.16 mg GAE/100 g) and flavonoid content (155.26 ± 2.90 μg quercetin/100 g) whereas highest DPPH radical scavenging activity with an IC₅₀ value of 29.8 ± 0.20 g and a FRAP value of 7291.60 ± 584.6 μM Fe(II)/100 g were noted in Shillong sample. Sonication exhibited various effects on the bioactive properties of the selected honey samples based on their source and treatment time. Honey from Jorhat and Sohra exhibited good quality standards with HMF content less than 80 mg/kg.

Effect of sweeteners on anthocyanin stability and colour properties of sour cherry and strawberry nectars during storage

Effects of various sweeteners (sucrose, maltose syrup and honey) on individual anthocyanins, colour and turbidity in sour cherry (SCN) and strawberry nectars (SN) were investigated during 168 and 42 days of storage at 20 °C, respectively. In SCN, major anthocyanin was cyanidin-3-glucosylrutinoside (cyd-3-glu-rut), followed by cyanidin-3-rutinoside (cyd-3-rut), cyanidin-3-glucoside (cyd-3-glu) and cyanidin-3-sophoroside (cyd-3-soph). Maltose syrup increased stabilities of cyd-3-glu-rut (8%) and cyd-3-rut (4%), while honey reduced stabilities of all anthocyanins in SCN. Due to higher anthocyanin stability, maltose syrup for SCN was recommended. In SN, the major anthocyanin was pelargonidin-3-glucoside (pg-3-glu), followed by pelargonidin-3-rutinoside (pg-3-rut) and cyd-3-glu. Stabilities of anthocyanins (46-51%) and colour density (6-7%) in SN sweetened with honey were higher than that sweetened with sucrose and maltose syrup. Considering maximum wavelength (λ_max), absorbance value at λ_max (A_max), polymeric colour and colour density values together, copigmentation of anthocyanins occurred in SN sweetened with honey. This study is the first study showing copigmentation of anthocyanins with honey.

Honey for acute cough in children

BACKGROUND

Cough causes concern for parents and is a major cause of outpatient visits. Cough can impact quality of life, cause anxiety, and affect sleep in children and their parents. Honey has been used to alleviate cough symptoms. This is an update of reviews previously published in 2014, 2012, and 2010.

OBJECTIVES

To evaluate the effectiveness of honey for acute cough in children in ambulatory settings.

SEARCH METHODS

We searched CENTRAL (2018, Issue 2), which includes the Cochrane Acute Respiratory Infections Group's Specialised Register, MEDLINE (2014 to 8 February 2018), Embase (2014 to 8 February 2018), CINAHL (2014 to 8 February 2018), EBSCO (2014 to 8 February 2018), Web of Science (2014 to 8 February 2018), and LILACS (2014 to 8 February 2018). We also searched ClinicalTrials.gov and the World Health Organization International Clinical Trial Registry Platform (WHO ICTRP) on 12 February 2018. The 2014 review included searches of AMED and CAB Abstracts, but these were not searched for this update due to lack of institutional access.

SELECTION CRITERIA

Randomised controlled trials comparing honey alone, or in combination with antibiotics, versus no treatment, placebo, honey-based cough syrup, or other over-the-counter cough medications for children aged 12 months to 18 years for acute cough in ambulatory settings.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included six randomised controlled trials involving 899 children; we added three studies (331 children) in this update.We assessed two studies as at high risk of performance and detection bias; three studies as at unclear risk of attrition bias; and three studies as at unclear risk of other bias.Studies compared honey with dextromethorphan, diphenhydramine, salbutamol, bromelin (an enzyme from the Bromeliaceae (pineapple) family), no treatment, and placebo. Five studies used 7-point Likert scales to measure symptomatic relief of cough; one used an unclear 5-point scale. In all studies, low score indicated better cough symptom relief.Using a 7-point Likert scale, honey probably reduces cough frequency better than no treatment or placebo (no treatment: mean difference (MD) -1.05, 95% confidence interval (CI) -1.48 to -0.62; I² = 0%; 2 studies; 154 children; moderate-certainty evidence; placebo: MD -1.62, 95% CI -3.02 to -0.22; I² = 0%; 2 studies; 402 children; moderate-certainty evidence). Honey may have a similar effect as dextromethorphan in reducing cough frequency (MD -0.07, 95% CI -1.07 to 0.94; I² = 87%; 2 studies; 149 children; low-certainty evidence). Honey may be better than diphenhydramine in reducing cough frequency (MD -0.57, 95% CI -0.90 to -0.24; 1 study; 80 children; low-certainty evidence).Giving honey for up to three days is probably more effective in relieving cough symptoms compared with placebo or salbutamol. Beyond three days honey probably had no advantage over salbutamol or placebo in reducing cough severity, bothersome cough, and impact of cough on sleep for parents and children (moderate-certainty evidence). With a 5-point cough scale, there was probably little or no difference between the effects of honey and bromelin mixed with honey in reducing cough frequency and severity.Adverse events included nervousness, insomnia, and hyperactivity, experienced by seven children (9.3%) treated with honey and two children (2.7%) treated with dextromethorphan (risk ratio (RR) 2.94, 95% Cl 0.74 to 11.71; I² = 0%; 2 studies; 149 children; low-certainty evidence). Three children (7.5%) in the diphenhydramine group experienced somnolence (RR 0.14, 95% Cl 0.01 to 2.68; 1 study; 80 children; low-certainty evidence). When honey was compared with placebo, 34 children (12%) in the honey group and 13 (11%) in the placebo group complained of gastrointestinal symptoms (RR 1.91, 95% CI 1.12 to 3.24; I² = 0%; 2 studies; 402 children; moderate-certainty evidence). Four children who received salbutamol had rashes compared to one child in the honey group (RR 0.19, 95% CI 0.02 to 1.63; 1 study; 100 children; moderate-certainty evidence). No adverse events were reported in the no-treatment group.

AUTHORS' CONCLUSIONS

Honey probably relieves cough symptoms to a greater extent than no treatment, diphenhydramine, and placebo, but may make little or no difference compared to dextromethorphan. Honey probably reduces cough duration better than placebo and salbutamol. There was no strong evidence for or against using honey. Most of the children received treatment for one night, which is a limitation to the results of this review. There was no difference in occurrence of adverse events between the honey and control arms.

Recent Advances in the Analysis of Phenolic Compounds in Unifloral Honeys

Honey is one of the most renowned natural foods. Its composition is extremely variable, depending on its botanical and geographical origins, and the abundant presence of functional compounds has contributed to the increased worldwide interest is this foodstuff. In particular, great attention has been paid by the scientific community towards classes of compounds like phenolic compounds, due to their capability to act as markers of unifloral honey origin. In this contribution the most recent progress in the assessment of new analytical procedures aimed at the definition of the qualitative and quantitative profile of phenolic compounds of honey have been highlighted. A special emphasis has been placed on the innovative aspects concerning the extraction procedures, along with the most recent strategies proposed for the analysis of phenolic compounds. Moreover, the centrality of validation procedures has been claimed and extensively discussed in order to ensure the fitness-for-purpose of the proposed analytical methods. In addition, the exploitation of the phenolic profile as a tool for the classification of the botanical and geographical origin has been described, pointing out the usefulness of chemometrics in the interpretation of data sets originating from the analysis of polyphenols. Finally, recent results in concerning the evaluation of the antioxidant properties of unifloral honeys and the development of new analytical approaches aimed at measuring this parameter have been reviewed.

Pharmacokinetics of Maleic Acid as a Food Adulterant Determined by Microdialysis in Rat Blood and Kidney Cortex

Maleic acid has been shown to be used as a food adulterant in the production of modified starch by the Taiwan Food and Drug Administration. Due to the potential toxicity of maleic acid to the kidneys, this study aimed to develop an analytical method to investigate the pharmacokinetics of maleic acid in rat blood and kidney cortex. Multiple microdialysis probes were simultaneously inserted into the jugular vein and the kidney cortex for sampling after maleic acid administration (10 or 30 mg/kg, i.v., respectively). The pharmacokinetic results demonstrated that maleic acid produced a linear pharmacokinetic phenomenon within the doses of 10 and 30 mg/kg. The area under concentration versus time curve (AUC) of the maleic acid in kidney cortex was 5-fold higher than that in the blood after maleic acid administration (10 and 30 mg/kg, i.v., respectively), indicating that greater accumulation of maleic acid occurred in the rat kidney.

Honey: Chemical composition, stability and authenticity

The aim of this review is to describe the chemical characteristics of compounds present in honey, their stability when heated or stored for long periods of time and the parameters of identity and quality. Therefore, the chemical characteristics of these compounds were examined, such as sugars, proteins, amino acids, enzymes, organic acids, vitamins, minerals, phenolic and volatile compounds present in honey. The stability of these compounds in relation to the chemical reactions that occur by heating or prolonged storage were also discussed, with increased understanding of the behavior regarding the common processing of honey that may compromise its quality. In addition, the identity and quality standards were described, such as sugars, moisture, acidity, ash and electrical conductivity, color, 5-HMF and diastase activity, along with the minimum and maximum limits established by the Codex Alimentarius.

Determination of ultra-trace organic acids in Masson pine (Pinus massoniana L.) by accelerated solvent extraction and liquid chromatography-tandem mass spectrometry

An accelerated solvent extraction (ASE)-solid-phase extraction (SPE)-liquid chromatography with electrospray ionization-tandem mass spectrometry (ASE-SPE-LC-ESI-MS/MS) methodology was developed for the extraction, cleanup and quantification of ultra-trace organic acids in Masson pine (Pinus massoniana L.) tissues. The separation was carried out on a Bio-Rad Aminex HPX-87H sulfonic column with an eluent containing 5 mmol L(-1) H₂SO₄ at a flow rate of 0.5 mL min(-1). A linear ion trap mass spectrometer equipped with electrospray ionization (ESI) source was operated in negative ion mode, and the six organic acids were eluted within 20 min. ASE extraction, SPE cleanup and LC-ESI-MS/MS analysis conditions were optimized to obtain reliable information about plant organic acid composition. Selective reaction monitoring (SRM) was employed for quantitative measurement. Intra-day precisions averaged 6.7%, and inter-day precisions were 2.1-10.7% for organic acid measurements in the pine samples. External standard calibration curves were linear over the range of 16.5-5000 ng L(-1), and detection limits based on a signal-to-noise ratio of three were at 0.5-5.0 ng L(-1). The results obtained showed the sensibility of the method was better than that of previously described HPLC methodology, and had no significant matrix effect. The proposed ASE-SPE-LC-ESI-MS/MS method is sensitive and reliable for the determination of ultra-trace organic acids in plant samples, despite the presence of the particularly complex matrix.

Honey for acute cough in children

BACKGROUND

Cough causes concern for parents and is a major cause of outpatient visits. It can impact on quality of life, cause anxiety and affect sleep in parents and children. Several remedies, including honey, have been used to alleviate cough symptoms.

OBJECTIVES

To evaluate the effectiveness of honey for acute cough in children in ambulatory settings.

SEARCH METHODS

We searched CENTRAL (2014, Issue 10), MEDLINE (1950 to October week 4, 2014), EMBASE (1990 to November 2014), CINAHL (1981 to November 2014), Web of Science (2000 to November 2014), AMED (1985 to November 2014), LILACS (1982 to November 2014) and CAB abstracts (2009 to January 2014).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing honey given alone, or in combination with antibiotics, versus nothing, placebo or other over-the-counter (OTC) cough medications to participants aged from one to 18 years for acute cough in ambulatory settings.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened search results for eligible studies and extracted data on reported outcomes.

MAIN RESULTS

We included three RCTs, two at high risk of bias and one at low risk of bias, involving 568 children. The studies compared honey with dextromethorphan, diphenhydramine, 'no treatment' and placebo for the effect on symptomatic relief of cough using a seven-point Likert scale. The lower the score, the better the cough symptom being assessed.Moderate quality evidence showed that honey may be better than 'no treatment' in reducing the frequency of cough (mean difference (MD) -1.05; 95% confidence interval (CI) -1.48 to -0.62; I(2) statistic 23%; two studies, 154 participants). High quality evidence also suggests that honey may be better than placebo for reduction of cough frequency (MD -1.85; 95% Cl -3.36 to -0.33; one study, 300 participants). Moderate quality evidence suggests that honey does not differ significantly from dextromethorphan in reducing cough frequency (MD -0.07; 95% CI -1.07 to 0.94; two studies, 149 participants). Low quality evidence suggests that honey may be slightly better than diphenhydramine in reducing cough frequency (MD -0.57; 95% CI -0.90 to -0.24; one study, 80 participants).Adverse events included mild reactions (nervousness, insomnia and hyperactivity) experienced by seven children (9.3%) from the honey group and two (2.7%) from the dextromethorphan group; the difference was not significant (risk ratio (RR) 2.94; 95% Cl 0.74 to 11.71; two studies, 149 participants). Three children (7.5%) in the diphenhydramine group experienced somnolence (RR 0.14; 95% Cl 0.01 to 2.68; one study, 80 participants). When honey was compared with placebo, four children (1.8%) in the honey group and one (1.3%) from the placebo group complained of gastrointestinal symptoms (RR 1.33; 95% Cl 0.15 to 11.74). However, there was no significant difference between honey versus dextromethorphan, honey versus diphenhydramine or honey versus placebo. No adverse event was reported in the 'no treatment' group.

AUTHORS' CONCLUSIONS

Honey may be better than 'no treatment', diphenhydramine and placebo for the symptomatic relief of cough, but it is not better than dextromethorphan. None of the included studies assessed the effect of honey on 'cough duration' because intervention and follow-up were for one night only. There is no strong evidence for or against the use of honey.

Identification, quantification and carbon stable isotopes determinations of organic acids in monofloral honeys. A powerful tool for botanical and authenticity control

RATIONALE

The analytical composition and botanical origin of honey are basic data used to determine the quality of this foodstuff. Although proteins are used to characterise the analytical composition of honey, they can be eliminated during its ultrafiltration and, in the case of honeys not saturated with their own pollen, the use of proteins does not work well. As acidity is a well-known characteristic of honey and organic acids are present at around 0.5% in honey, we therefore investigated an alternative method to the protein-based White method, using organic acids as new internal standards instead of proteins.

METHODS

The qualitative and quantitative analyses of 14 organic acids were carried out by ion chromatography with an electrochemical detector. The (13)C/(12)C isotopic ratios of the honeys, and of the organic acids extracted from them with an anion exchange resin, were determined by isotope ratio mass spectrometry.

RESULTS

Gluconic acid is the predominant organic acid in honey, at between 1.8 and 12.7 g/kg. For fir honey the major acid is galacturonic acid at around 4.6 g/kg. The isotopic ratios of honeys and of their acids are strongly linked. Correlations between the δ(13)C values of the honey and the acids were significant, and better than those obtained using proteins.

CONCLUSIONS

This study has provided a method to differentiate honeys from seven botanical origins, based on organic acid analysis. By combining various organic acid contents and isotopic ratio values through statistical processing by Principal Component Analysis it is possible to differentiate honey samples as a function of their botanical origin.

Botanical origin causes changes in nutritional profile and antioxidant activity of fermented products obtained from honey

Honey as rich source of enzymatic and nonenzymatic antioxidants serves as health-promoting nutrient in the human body. Here, we present the first time a comparative study of nutritional profiles (e.g., acidities, sugar, organic acid profile, total polyphenolic, flavonoid content) for different unifloral, multifloral honeys and their fermented products, in correlation with their antioxidant activity. Additionally, an optimized method for HPLC separation of organic acids from honey was established. The total phenolic content of honey samples varied widely among the honey types compared to fermented products. High amounts of total flavonoids were quantified in heather honey, followed by raspberry, multifloral, black locust, and linden honey. A positive correlation between the content of polyphenols, flavonoids, and antioxidant activity was observed in honey samples. After fermentation, the flavonoid content of dark honey fermented products decreased significantly. Black locust and linden honeys are more suitable for fermentation because the decrease in antioxidant substances is less pronounced.

Ion-exclusion chromatography determination of organic acid in uridine 5'-monophosphate fermentation broth

Simultaneous determination of organic acids using ion-exclusion liquid chromatography and ultraviolet detection is described. The chromatographic conditions are optimized when an Aminex HPX-87H column (300 × 7.8 mm) is employed, with a solution of 3 mmol/L sulfuric acid as eluent, a flow rate of 0.4 mL/min and a column temperature of 60°C. Eight organic acids (including orotic acid, α-ketoglutaric acid, citric acid, pyruvic acid, malic acid, succinic acid, lactic acid and acetic acid) and one nucleotide are successfully quantified. The calibration curves for these analytes are linear, with correlation coefficients exceeding 0.999. The average recovery of organic acids is in the range of 97.6% ∼ 103.1%, and the relative standard deviation is in the range of 0.037% ∼ 0.38%. The method is subsequently applied to obtain organic acid profiles of uridine 5'-monophosphate culture broth fermented from orotic acid by Saccharomyces cerevisiae. These data demonstrate the quantitative accuracy for nucleotide fermentation mixtures, and suggest that the method may also be applicable to other biological samples.

Honey for acute cough in children

BACKGROUND

Cough causes concern for parents and is a major cause of outpatient visits. It can impact on quality of life, cause anxiety and affect sleep in parents and children. Several remedies, including honey, have been used to alleviate cough symptoms.

OBJECTIVES

To evaluate the effectiveness of honey for acute cough in children in ambulatory settings.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2011) which contains the Cochrane Acute Respiratory Infections Group's Specialised Register; MEDLINE (1950 to December week 4, 2011); EMBASE (1990 to January 2012); CINAHL (1981 to January 2012); Web of Science (2000 to January 2012); AMED (1985 to January 2012); LILACS (1982 to January 2012); and CAB abstracts (2009 to January 2012).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing honey given alone, or in combination with antibiotics, versus nothing, placebo or other over-the-counter (OTC) cough medications to participants aged from two to 18 years for acute cough in ambulatory settings.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened search results for eligible studies and extracted data on reported outcomes.

MAIN RESULTS

We included two RCTs of high risk of bias involving 265 children. The studies compared the effect of honey with dextromethorphan, diphenhydramine and 'no treatment' on symptomatic relief of cough using the 7-point Likert scale.Honey was better than 'no treatment' in reducing frequency of cough (mean difference (MD) -1.07; 95% confidence interval (CI) -1.53 to -0.60; two studies; 154 participants). Moderate quality evidence suggests honey did not differ significantly from dextromethorphan in reducing cough frequency (MD -0.07; 95% CI -1.07 to 0.94; two studies; 149 participants). Low quality evidence suggests honey may be slightly better than diphenhydramine in reducing cough frequency (MD -0.57; 95% CI -0.90 to -0.24; one study; 80 participants).Adverse events included mild reactions (nervousness, insomnia and hyperactivity) experienced by seven children (9.3%) from the honey group and two (2.7%) from the dextromethorphan group; the difference was not significant (risk ratio (RR) 2.94; 95% Cl 0.74 to 11.71; two studies; 149 participants). Three children (7.5%) in the diphenhydramine group experienced somnolence (RR 0.14; 95% Cl 0.01 to 2.68; one study; 80 participants) but there was no significant difference between honey versus dextromethorphan or honey versus diphenhydramine. No adverse event was reported in the 'no treatment' group.

AUTHORS' CONCLUSIONS

Honey may be better than 'no treatment' and diphenhydramine in the symptomatic relief of cough but not better than dextromethorphan. There is no strong evidence for or against the use of honey.

Gas chromatographic determination of 29 organic acids in foodstuffs after continuous solid-phase extraction

A simple and expeditious method based on continuous solid-phase extraction and gas chromatography-mass spectrometry (GC-MS) was reported for the direct determination of 29 organic acids in food and beverages. A sorbent column packed with 80 mg of LiChrolut EN-Supelclean ENVI-18 (1:1) was employed for extraction and clean-up purposes. After elution with 200 μL of methanol, the methanolic extract was directly injected into the GC-MS without prior derivatization. The method provided good linearity (0.5-1000 μg kg(-1)) and fairly good precision for all compounds (RSD lower than 6.2%). The recoveries of the organic acids from diluted samples that were spiked at three different concentrations (10, 40 and 100 μg kg(-1)) ranged from 93 to 98%. The applicability of the method was demonstrated by analyzing the target compounds in a wide variety of foodstuffs including beer, wine, fruit juice, soy sauce, soya milk and honey samples.

Chemical composition, characterization, and differentiation of honey botanical and geographical origins

Botanical and biographical origins of honey are an important issue in food quality and safety. This chapter focuses on use of chemical components to determine botanical and geographical origins of honey. The botanical and geographical origins of the nectar are related with the chemical composition of honey. Honey can originate from single and multiplant species. In general, the prices of honey from single plant species are much higher than those of common polyfloral honey because of consumer preferences. Single and multiple chemicals and components can well indicate the botanical and geographical origins of the honey. Marker chemicals and components include flavonoids, pollen, aroma compounds, oligosaccharides, trace elements, amino acids, and proteins. If multiple chemicals are used as markers, patterns of the chemicals are often used to detect the botanical and geographical origins of honey. Modern statistical software in combination with advanced analytical instrumentation provides high potential for the differentiation of the botanical and geographical origins of the honey.