Quality Control Of Propolis Research Articles

English

Analytical approaches utilized for the characterization of polyphenols from propolis useful for the determination of its quality is investigated in this study. A qualitative and quantitative evaluation of propolis bioactive molecules is of interest in medicine and nutraceuticals. Recent powerful analytical techniques are of great utility to separate and quantify polyphenols in extracts and finished products due to their capacity to produce typical fingerprints and a reliable identification of many components. According to this, an HPLC-UV-MS procedure was validated and applied for the characterization and quantification of bioactive substances in propolis and for an accurate assessment of their content in extract samples. By using this analytical approach, we obtained specific compositions related to brown propolis acquired from different geographic areas (and preparations and treatment). This is more important by considering the scientific opinion of European Food Safety Authority (EFSA) which provided a negative response related to health claims of propolis and its polyphenols. These results prove that HPLC-MS is an attractive tool for the standardization and quality control of propolis and may be realistically applied to screen raw material and to evaluate finished commercial preparations and nutraceutical benefits. Key words: Propolis, polyphenols, flavonoids, phenolic acids, high-performance liquid chromatography-mass spectrometry (HPLC-MS), quality control, standardization

A Great Concern Regarding the Authenticity Identification and Quality Control of Chinese Propolis and Brazilian Green Propolis

Propolis (bee glue) is a natural resin mixture produced by honey bees and it is composed of substances collected from parts of plants, buds and exudates. The composition of propolis varies primary on the geographical locations of the ingredients obtained by the bees. A series of biological properties of propolis including anti-microbial, immunostimulatory, anti-inflammatory, anti-tumor and anti-oxidation activities have been reported in relation to their chemical composition, plant origin and geographical area. This review collates the scientific literature regarding Chinese propolis and Brazilian green propolis, specifically focusing on their different constituents and biological activities. While there are known differences in composition of these two kinds of propolis, they share considerable similarity in their overall chemical composition. Importantly, techniques such as principal component analysis (PCA) and fingerprint are viable options for authenticity identification and quality control of propolis. Many of the molecular mechanisms driving various biological activities of propolis have been determined. We have also found that the biological activity of propolis mainly depends on its constituents, such as flavonoids or phenolic compounds. Each activity is regulated by a variety of biological pathways. The compounds in both Chinese propolis and Brazilian green propolis were found to participate in different biological pathways through distinct molecular mechanisms due to their diverse chemical compositions and unique structures. With the growing market interest of Brazilian green propolis in China, an evaluation between the chemical diversity and biological activity of Chinese propolis and Brazilian green propolis are in need of a review.

Bioprofiling for the quality control of Egyptian propolis using an integrated NIR-HPTLC-image analysis strategy

Quality control of propolis being a complex mixture of compounds that are very difficult to analyze and standardize is certainly challenging. Shown on the example of 35 Egyptian propolis samples, a strategy for an improved quality control was demonstrated in which efficacy-directed fingerprint analysis of high-performance thin-layer chromatography (HPTLC) fingerprints were evaluated in combination with Near Infra-Red spectrometry (NIRS) to realize precise discrimination and high quality assessment of chemical and effective consistency of propolis samples that are collected from various geographical locations in Egypt. The fingerprints obtained after derivatization and fluorescence detection (FLD) at λ 366 nm were analyzed by using multivariate data analysis and data were used to identify nine marker ingredients of the different propolis samples. These markers were then quantified by a new validated HPTLC method and an attempt to classify the samples by using a targeted approach was implemented. All investigated propolis samples were initially divided into two types in the untargeted and targeted HPTLC image multivariate analysis. The antimicrobial activities of propolis samples were then evaluated and the results showed that there was significant variation in the biological activities of the different samples. The quantitative data of marker compounds as well as the samples bioactivity results were then subjected to partial least squares regression (PLS-R) analysis which revealed that chrysin, galangin‑5‑O‑methylether, pinostrobin, and islapinin were the main bioactive markers. Based on the efficacy-associated marker ingredients, pretreated spectral patterns of NIRS were selected as a complementary evaluation technique directed to the comprehensive efficacy-directed discrimination of the different Egyptian propolis samples which could successfully classify the propolis samples tested into three different types. Hierarchical cluster analysis and orthogonal projection to latent structures discriminant analysis (OPLS-DA) were applied to the quantitative results from the efficacy-associated markers only. From this systematic method, the 35 samples were subsequently divided into three types; orange, green and blue, displaying a more intricate division than OPLS-DA which is based only on the untargeted HPTLC analysis or the full NIR spectral data. This study initiated the research on the Egyptian propolis and confirmed the existence of three different types of Egyptian propolis, the blue, green and orange types. The study also emphasizes how it is critical to implement the fingerprint- efficacy relationship analysis in finding out the main health-relevant biomarkers for the quality assessment especially for samples displaying delicate differences in their chemical composition and bioactivity.

Cyclic voltammetry and UV/Vis spectroscopy in combination with multivariate data analysis for the assessment of authenticity of poplar type propolis

Propolis, as a beneficial natural product, has found application in the food and pharmaceutical industries as a food preservative, active packaging material as well as a main component of propolis containing products. Quality control of propolis has thus gained in importance. We used simple, fast, and low-cost techniques such as UV/Vis spectrophotometry and cyclic voltammetry applied in combination with principal component analysis to confirm the presence of two botanical sub-types of propolis. Cyclic voltammetry, as a green, sensitive, and convenient technique suitable for investigation of chemical profile, together with multivariate chemometrics technique, was used for the first time for characterization and classification of propolis. UV/Vis spectroscopy was applied in two aspects, absorption at certain wavelength for the quantitative determination of analytes, i.e. determination of quality control parameters, and spectral profiles, for the confirmation of the existence of two botanically different poplar types. All investigated Serbian propolis samples were characterized with specific chemical patterns and were classified in two main botanical varieties, so-called orange and blue. The results confirmed that the applied methods have a potential to be used for the discrimination of complex natural products such as propolis.

16 Discrimination of Brazilian green propolis and Chinese propolis based on high-performance liquid chromatographic fingerprints and multivariate statistical analysis

Objectives The determination of chemical components is usually used in the quality control of propolis. However, chemical components from different types of propolis are similar. The objective of this investigation was to establish a method based on a specific chemical fingerprint profile and a multivariate mixed model statistical analysis which could easily distinguish propolis of different origins and promote the quality control of propolis. Methods A novel approach using high performance liquid chromatography (HPLC) coupled with multivariate statistical analysis was established for profiling and distinguishing Chinese and Brazilian green propolis. A batch of 22 propolis samples was analyzed, and the datasets on retention time, peak area and sample codes were subjected to mixed multivariate statistical analysis consisting of principal component analysis (PCA) and a self-organization mapping net (SOM). Results The fingerprints were profiled. PCA score plots showed Chinese and Brazilian green propolis clearly classified into two groups. The visualized SOM results showed data from the two groups projected to the adjacent neurons clearly separated from each other. Artepillin C, which contributed greatly to the differentiation, was screened out and identified as the reference compound. Artepillin C is the characteristic component in Brazilian propolis which can be used as chemical marker to distinguish propolis of different origins. Conclusions In this study, fingerprints coupled with multivariate statistical analysis have been successfully applied to distinguish Chinese from Brazilian green propolis. The research identified a chemical marker, and thus helps to investigate and promote the quality control of propolis.

Profiling and classification of French propolis by combined multivariate data analysis of planar chromatograms and scanning direct analysis in real time mass spectra

Quality control of propolis is challenging, as it is a complex natural mixture of compounds, and thus, very difficult to analyze and standardize. Shown on the example of 30 French propolis samples, a strategy for an improved quality control was demonstrated in which high-performance thin-layer chromatography (HPTLC) fingerprints were evaluated in combination with selected mass signals obtained by desorption-based scanning mass spectrometry (MS). The French propolis sample extracts were separated by a newly developed reversed phase (RP)-HPTLC method. The fingerprints obtained by two different detection modes, i.e. after (1) derivatization and fluorescence detection (FLD) at UV 366nm and (2) scanning direct analysis in real time (DART)-MS, were analyzed by multivariate data analysis. Thus, RP-HPTLC-FLD and RP-HPTLC-DART-MS fingerprints were explored and the best classification was obtained using both methods in combination with pattern recognition techniques, such as principal component analysis. All investigated French propolis samples were divided in two types and characteristic patterns were observed. Phenolic compounds such as caffeic acid, p-coumaric acid, chrysin, pinobanksin, pinobanksin-3-acetate, galangin, kaempferol, tectochrysin and pinocembrin were identified as characteristic marker compounds of French propolis samples. This study expanded the research on the European poplar type of propolis and confirmed the presence of two botanically different types of propolis, known as the blue and orange types.

Validation of GC-MS method for determination of varroacide residues in propolis

Propolis is a resinous material collected by honeybees (Apis mellifera L.) from various plants and enriched with bee salivary gland secretions and wax. Number of factors, such as beekeeping practice, can affect the quality and consequently the therapeutic value of propolis and its preparations. The most important source of propolis contamination is improper administration of varroacides that have to be used for long-term control of honeybee mite Varroa destructor. Therefore, the analysis of these noxious substances is essential in quality control of propolis. In this study the method based on the extraction with n-hexane followed by purifying of extract on florisil column was used prior to sample analysis. Purified extracts were analyzed by gas chromatography-mass spectrometry hyphenated technique. The procedure was optimized and validated for the determination of bromopropylate, amitraz and coumaphos residues in propolis. Investigated validation parameters of applied procedure were selectivity, linearity, precision, accuracy, robustness and limits of detection (LOD) and quantification (LOQ). All these parameters satisfied the ICH criteria [1] in the test samples of standards mixture for all three examined compounds. The applied method for varroacide analysis in validation sample of propolis was suitable for determination of bromopropylate and coumaphos. Recoveries were 100% for bromopropylate and 63% for coumaphos with LOQ of 0.08 and 1.5µg/g, respectively. On the other hand, the procedure was inappropriate for determination of amitraz, probably due to its instability in complex matrix of propolis as was previously described for honey and beeswax [2].