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Determination of the total phenolic, flavonoid and antioxidant activity of Sabalan Honey
2017
Kamkar, Abolfazl | Khodabakhshiyan, Sara
BACKGROUND: Honey is recognized as having different biological properties including antioxidant effects. Phenolic acids and flavonoids are the main antioxidant in this apiary product. OBJECTIVES: In this study eight samples of Sabalan honey were screened to evaluate the antioxidant activity, total phenolic and flavonoid content. METHODS: Antioxidant activity of honey samples was determined by DPPH (2,2-diphenyl-1-picryl hydrazyl) method and β-carotene bleaching assay, total phenolic and flavonoid by Folin-Ciocalteu and Aluminium chloride methods, in addition, in all samples, some physicochemical parameters (pH, acidity, diastase activity, existence or nonexistence of HMF) were measured according to Iranian National Standardization N92. Data were analyzed using ANOVA (one-way). RESULTS: Total phenolic and flavonoid content of honeys ranged respectively from 15.71- 41.58 (mg GAE/100g honey) and 3.80-13.20 (mg QE/100g honey). Antioxidant activity was between 23.19%-94.25%, β-carotene bleaching inhibition 69.54%-85.69%, pH ranged from 3.63-3.83, Acidity 11.99-20.50 mEq/kg , diastase activity of all samples was negative except sample No.1. All samples had positive HMF results. CONCLUSIONS: Regarding the above results, it could be concluded that the honey samples have significant antioxidant activity. All parameters of physicochemical test were according to the international specifications except diastase and HMF tests, which may be due to improper processing and storage condition, heating treatment, old honey,etc.
Afficher plus [+] Moins [-]The Effect of Storage Time and Container on Physicochemical Parameter of Kurdistan Honey
2018
Khanbabaie, hooman | Khezri, Mohammad | Bahmani, Hamid Reza | Salehi, Saleh
BACKGROUND: Honey is an excellent food product with health-giving characteristics. On the other hand, the honey quality can change based on various factors. OBJECTIVES: Physicochemical experiments intend to investigate the honey quality in four geographic directions of Kurdistan province shelf-life and the containers the honey is placed in. METHODS: In this research, totally 96 samples from 4 apiaries in various parts of the province were prepared and maintained in various dishes/containers and various (time) periods at 25.5±3.5 °C. After preparing the samples, some factors including moisture, reducing sugars, sucrose, pH, acidity, the ratio of fructose to glucose, ash, diastase, hydroxyl methyl furfural were evaluated. RESULTS: The result showed the moisture total average, reducing sugars, sucrose, pH, acidity, the ratio of fructose to glucose, and ash were 13.79%, 77.67%, 2.22%, 3.86, and 21.39 of meq/kg, 1.09% and 0.13%, respectively. Qualitative examinations showed, there was the distance in all samples but no HME. With the increase in shelf-life time, metabolites in the ratio of fructose to glucose and acidity increased significantly, but the factors, moisture, pH were reduced significantly (P<0.05). Various containers had no significant impact on physicochemical characteristics of honey. CONCLUSIONS: Generally, one can say that the comparison between the obtained amounts with the current standards, quality of the honey samples were standard and favorable. According to the results of this study, honey can remain at room temperature in different containers for 9 months and maintain anacceptable quality.
Afficher plus [+] Moins [-]Pyrrolizidine alkaloids in honey: determination with liquid chromatography-mass spectrometry method
2018
Kowalczyk, Ewelina | Kwiatek, Krzysztof
Pyrrolizidine alkaloids (PAs) are probably the most widespread toxins of natural origin. More than 6,000 plant species produce these toxic compounds. Bees can forage on flowers of plants producing PAs, which leads to contamination of honey with the toxic compounds. To determine the contamination of honey with PAs, a sensitive method based on liquid chromatography coupled with mass spectrometry has been developed. PAs were extracted with 0.05 M sulphuric acid and purified with MCX cartridges. A solvent mixture consisting of ethyl acetate, methanol, acetonitrile, ammonia, and triethylamine (8:1:1:0.1:0.1, v/v) was used to wash alkaloids from the cartridges. After evaporation the residues were reconstituted in water and methanol mixture and subjected to LC–MS analysis. The developed method was validated according to SANTE/11945/2015 requirements. The recovery was from 80.6% to 114.5%. The repeatability ranged from 2.3% to 14.6%, and the reproducibility was from 4.9% to 17.7%. A new method for the determination of PAs in honey has been developed and validated. All evaluated parameters were in accordance with the SANTE/11945/2015 guidance document. Out of 50 analysed honey samples, 16 (32%) were positive for the content of at least one PA.
Afficher plus [+] Moins [-]Clostridium perfringens spores in Polish honey samples
2018
Grenda Tomasz | Grabczak Magdalena | Goldsztejn Magdalena | Kozieł Nina | Kwiatek Krzysztof | Pohorecka Krystyna | Skubida Marta | Bober Andrzej
The aim of this study was examination of honey samples collected from apiaries situated in all Polish provinces for occurrence of Clostridium spp., especially C. perfringens.
Afficher plus [+] Moins [-]Pyrrolizidine alkaloids in honey: determination with liquid chromatography-mass spectrometry method
2018
Kowalczyk Ewelina | Kwiatek Krzysztof
Pyrrolizidine alkaloids (PAs) are probably the most widespread toxins of natural origin. More than 6,000 plant species produce these toxic compounds. Bees can forage on flowers of plants producing PAs, which leads to contamination of honey with the toxic compounds. To determine the contamination of honey with PAs, a sensitive method based on liquid chromatography coupled with mass spectrometry has been developed.
Afficher plus [+] Moins [-]Comparison of transfer of different sulphonamides from contaminated beeswax to honey
2024
Mitrowska Kamila | Antczak Maja
No maximum residue limits in honey have been legislated in the EU for antimicrobial substances such as sulphonamides, and they are not permitted, therefore, for treating honey bees unless in a cascade system. Since sulphonamides are used illegally in apiculture to treat foulbrood, their residues can be found in honey and other apiculture products, including beeswax. The study aimed to assess the contamination of honey from beeswax containing residues of 10 sulphonamides (sulphadimethoxine (SDM), sulphadoxine (SDX), sulphamonomethoxine (SMM), sulphamethoxazole (SMX), sulphameter (SMT), sulphamethazine (SMZ), sulphamerazine (SMR), sulphadiazine (SDA), sulphathiazole (STZ) and sulphacetamide (SCA)).
Afficher plus [+] Moins [-]Simultaneous determination of pyrrolizidine and tropane alkaloids in honey by liquid chromatography–mass spectrometry
2022
Kowalczyk, Ewelina | Kwiatek, Krzysztof
Pyrrolizidine alkaloids (PAs) and tropane alkaloids (TAs) are natural contaminants of honey and respectively hepatoxic and neurotoxic compounds. Because honey is a popular constituent of the human diet, it is relevant to warrant the safety of the product. For that reason, a method for simultaneous determination of PAs and TAs in honey based on liquid chromatography– mass spectrometry was developed. The analytical protocol used sulphuric acid extraction and solid-phase extraction purification. The developed procedure was subjected to validation in terms of linearity, selectivity, repeatability, reproducibility, limits of quantification and determination, matrix effect and uncertainty. A total of 29 honey samples were analysed for the determination of PAs and TAs. All the evaluated validation parameters fulfilled the requirements of European Commission Decision 2002/657/EC. At least one of the monitored alkaloids was determined in 52% of the samples. Among the most abundant alkaloids were echimidine, intermedine and lycopsamine. The total PA concentrations ranged from 2.2 to 147.0 μg kg⁻¹. Contrastingly, none of the monitored TAs was detected in the analysed samples. An assessment of the dietary exposure to PAs from the consumption of the contaminated honeys showed that three of them would pose a risk to consumers, especially if they were children. A sensitive method suitable for simultaneous determination of PAs and TAs in honey was developed and validated. The analysis of 29 honey samples for PAs and TAs revealed that honey destined for retail could pose a risk to consumers.
Afficher plus [+] Moins [-]Amitraz marker residues in honey from honeybee colonies treated with Apiwarol
2018
Pohorecka Krystyna | Kiljanek Tomasz | Antczak Maja | Skubida Piotr | Semkiw Piotr | Posyniak Andrzej
Amitraz is a formamide exhibiting both acaricidal and insecticidal activity and is frequently used by beekeepers to protect honeybee colonies against Varroa destructor mites. The aim of this apiary trial was to evaluate the impact of honeybee colony fumigation with amitraz on the level of contamination of honey stored in combs.
Afficher plus [+] Moins [-]Simultaneous determination of pyrrolizidine and tropane alkaloids in honey by liquid chromatography–mass spectrometry
2022
Kowalczyk Ewelina | Kwiatek Krzysztof
Pyrrolizidine alkaloids (PAs) and tropane alkaloids (TAs) are natural contaminants of honey and respectively hepatoxic and neurotoxic compounds. Because honey is a popular constituent of the human diet, it is relevant to warrant the safety of the product. For that reason, a method for simultaneous determination of PAs and TAs in honey based on liquid chromatography– mass spectrometry was developed.
Afficher plus [+] Moins [-]Amitraz marker residues in honey from honeybee colonies treated with Apiwarol
2018
Pohorecka, Krystyna | Kiljanek, Tomasz | Antczak, Maja | Skubida, Piotr | Semkiw, Piotr | Posyniak, Andrzej
Amitraz is a formamide exhibiting both acaricidal and insecticidal activity and is frequently used by beekeepers to protect honeybee colonies against Varroa destructor mites. The aim of this apiary trial was to evaluate the impact of honeybee colony fumigation with amitraz on the level of contamination of honey stored in combs. Experimental colonies were fumigated four times every four days with one tablet of Apiwarol per treatment. Honey was sampled from combs of brood chambers and combs of supers one day after each amitraz application and from harvested honey. Amitraz marker residues (as a total of amitraz and metabolites containing parts of molecules with properties specific to the 2,4-DMA group, expressed as amitraz) were evaluated in honey. All analysed samples were contaminated with amitraz metabolites. 2,4-DMA and DMPF were the most frequently determined compounds. The average concentration of amitraz marker residue in honey from groups where a smouldering tablet was located directly in beehives was significantly higher than that of residue in honey from groups with indirect smoke generation. No significant effect on the honey contamination deriving from the place where it was exposed to smoke (combs of brood chambers and supers) was noted. Amitraz marker residues exceeded the MRL in 10% of honey samples from combs. Fumigation of beehives with amitraz results in contamination of honey stored in combs.
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