|
|
Articles
by
Liviu Al. MARGHITAS |
Total Records (
10 ) for
Liviu Al. MARGHITAS |
|
 |
|
|
|
Anca Aurora POPA
,
Liviu Al. MARGHITAS
and
Cristina Bianca POCOL
|
|
Research meant to promote and extend beekeeping is undertaken in many countries
of the world. As part of the research that tries to find the factors that determine a revival of the
beekeeping sector, the present study analyses the factors that influence the probability of becoming an
entrepreneur in the beekeeping sector. The method used is the logistic regression, model that predicts
the probability of an event occurring for a given person. According to the results of the logistic
regression model, the following factors determine beekeepers intention to start an enterprise: the
modernization of the beekeeping exploitation, collaboration with other enterprises from the
beekeeping sector, belonging to a beekeeping association (different from Romanian Beekeepers
Association), the strategy to export beekeeping products and to create alliances with other enterprises,
the commercialization of bee products by distribution to a few stores and the age of beekeepers. The
present study emphasizes the role of beekeepers social capital and their ability to acquire modern
technology as two of the most important sources of opportunities that influence the emergence of new
and profitable beekeeping enterprises. |
|
|
|
|
Anca Aurora POPA
,
Liviu Al. MARGHITAS
and
Cristina Bianca POCOL
|
|
The aim of the present study is to develop a categorization of beekeepers from the
North-West Region of Romania using multiple correspondence analysis. Multiple
correspondence analysis is an extension of correspondence analysis which allows the analysis
of the pattern of relationships of several categorical dependent variables (Abdi and Valentin,
2007). The data was collected through a survey administered to a sample composed of 420
beekeepers from the North-West Region of Romania. The present categorization implies that
the beekeepers form the sample are grouped into categories according to their age and the
dimension of their beekeeping exploitation, for the specific purpose of distinguishing several
aspects that are specific to each category. The results of the analysis illustrate a relationship
between beekeepers and other factors such as: ways of commercializing beekeeping products,
propensity for European Union measures, opinions regarding the current legislation in the
beekeeping sector. Each category of beekeepers has its own characteristics and should be
addressed according to its specificity by public measures. The average age with average to
high beekeeping exploitation is characterized by greater openness to European Union Funding
Programmes and is specific for Family business or Sole Proprietorship. Openness to specific
measures for young beekeepers is obviously specific to young beekeepers with small
beekeeping exploitations and who prefer the distribution of their products to several stores.
Modernization trends are specific to beekeepers of average age and average beekeeping
exploitation size. Higher experience, advanced age and large-scale beekeeping exploitations
characterises the veterans in apiculture who are all discontented with the state measures in this
sector. Amateur beekeepers have a slightly above average age and want to sell their products
to friends or acquaintances. A categorization of beekeepers from the North-West Region of
Romania is extremely important for a better understanding of the factors and mechanisms that
determine the development of the sector. Taking into consideration the resource constraints
faced by beekeeping exploitations and their vulnerability to the environment, policy measures
must be implemented to support small scale beekeepers as well as beekeepers that have large
beekeeping exploitations. |
|
|
|
|
|
Liviu Al. MARGHITAS
,
Victorita BONTA
,
Daniel DEZMIREAN
and
Otilia BOBIS
|
|
The aim of the present work was the development, validation and implementation in routine analysis of a technique that guarantees low detection limit for chloramphenicol in honey using liquid chromatography (LC)-mass spectrometry (MS) with photodiode array (PDA) detection. Sample preparation was carried out by liquid-liquid extraction of a honey solution in phosphoric buffer (PBS, pH=7.8). The determinations were performed using a Zorbax Eclipse XDB-C18 column and gradient mobile phase, using an electrospray ionization source (ESI) in negative ion mode. Recoveries were calculated at three concentration levels and higher values than 85% were obtained, with relative standard deviations less than 7.7%. The applicability of the present method was tested on 12 honey samples purchased from different beekeepers from Transylvania. |
|
|
|
|
Gabriela BIRTAS
,
Liviu Al. MARGHITAS
,
Daniel DEZMIREAN
,
Oltica G. STANCIU
and
Mircea TAMAS
|
|
The objective of this study was to investigate the flavonoid content of propolis and poplar buds using a spectrofotometric method with zirconium oxychlorid reagent, according to the patented method of Tamas (1980). The flavonoid content of propolis ranged between 15.5% and 19.5% chrysin equivalent and 22.4% for poplar buds. The obtained results expressed in chrysin after the reaction with the zirconium reagent were similar with those obtained by other methods for the quantification of flavonoids in propolis samples. The vegetal resins of European propolis have the predominant origin from poplar buds. This proposed method is simple, reliable and fast, in comparison with other previous colorimetric methods utilized for the flavonoid content of propolis, requiring only one reagent witch reacts with all specific flavonoid compounds contained by propolis (flavones, flavonols and flavanones) permitting their total estimation. |
|
|
|
|
Otilia BOBIS
,
Liviu Al. MARGHITAS
,
Daniel DEZMIREAN
,
Olimpia MORAR
,
Victorita BONTA
and
Flore CHIRILA
|
|
The aim of this study was to determine the composition and microbiological quality of commercially honeybee-collected pollen, bee bread and royal jelly and to define the following physicochemical and microbiological characteristics: water content/dry weight, protein content, fat content, sugar spectrum and some microbiological parameters. The main sugars identified by high performance liquid chromatography were fructose, glucose, and sucrose, with small amounts of disaccharides. Among the microbiological parameters, a relatively high number of moulds and total aerobic counts were found in fresh pollen, but under the maximum admitted level. |
|
|
|
|
Rodica MARGAOAN
,
Liviu Al. MARGHITAS
,
Daniel DEZMIREAN
,
Cristina M. MIHAI
and
Otilia BOBIS
|
|
Pollen represents the male reproductive cells collected by honeybees from flower stamens. The nutritional and medicinal value of bee pollen is known for centuries. With orange to red pigments, it provides nutrition through its considerable amounts of proteins, sterols, vitamins, fatty acids, phenol compounds and other physiologically active compounds. As a healthy bee product, pollen is considered to be the first-rate reservoir of antioxidants. Worldwide interest in bee pollen has recently developed as more information on their chemical composition and physiological effects has become highlighted. Bee collected pollen is regarded as valuable special food, having different health enhancing effects, also used in apitherapy. Its value is given by the content in amino acids, lipids, carbohydrates, mineral salts, vitamins, polyphenols, carotenoids, which depends on the botanical source available to bees. |
|
|
|
|
Cristina M. MIHAI
and
Liviu Al. MARGHITAS
|
|
Propolis samples, used as biological material in the present study, were collected from different areas in Transylvania and investigated in order to establish their antioxidant capacity. The antioxidant properties were evaluated using 2,2-diphenyl-1-picrylhidrazyl (DPPH) radical scavenging capacity assay. IC50 values were also determined for the studied propolis samples. The lower the IC50 value is, the greater the overall effectiveness of the antioxidant in question. IC50 values for the investigated propolis samples ranged between 1.67mg/ml and 3.28mg/ml. The lowest IC50 value, 1.67mg/ml corresponding to sample PS 10 indicates a great antioxidant activity of the mentioned sample. |
|
|
|
|
Liviu Al. MARGHITAS
,
Olimpia MORAR
,
Otilia BOBIS
,
Victorita BONTA
,
Daniel DEZMIREAN
and
Melinda TOFALVI
|
|
The article presents the researches carried out with fresh royal jelly in different larvae stage. At the beginning, the initial material was analyzed on the content of nutritious substances. This type of work is extremely valuable for practical application in food science, therapy and nutritive supplements. In scientific word royal jelly has been accepted and used as nutritive substance complex, benefic for humans health. The primary objective of this study was to evaluate the physicochemical parameters of different samples of royal jelly in different larvae stage. The principal constituents of royal jelly are water, protein, sugars, lipids and mineral salts. Although they occur with notable variations, the composition of royal jelly remains relatively constant when comparing different colonies, bee races and time of harvesting. |
|
|
|
|
Daniel DEZMIREAN
,
Liviu Al. MARGHITAS
,
Otilia BOBIS
,
Laura STAN
,
Victoriţa BONTA
,
Ovidiu MAGHEAR
,
Georgeta DINITA
and
Olimpia MORAR
|
|
Romanian Calluna vulgaris honey that came from Cluj and Salaj County, the most important Calluna areas in Romania was evaluated for authenticity by pollen-analysis, several physical-chemical analyses, including sugar profile and mineral content. Physical-chemical and mineral content analyses show clearly that the samples taken for analysis were pure Calluna vulgaris honeys. This type of honey was found to have the highest potassium content from all the honeys in Romania that were analyzed in our laboratory. Statistical data were processed in order to develop a biochemical profile of this type of honey. |
|
|
|
|
Liviu Al. MARGHITAS
,
Cristian COROIAN
,
Daniel DEZMIREAN
,
Laura STAN
and
Emilia FURDUI
|
|
Honeybees from 21 locations from Moldova (Romania) were analyzed in order to study phylo-geographic distribution of Apis melllifera subspecies. The fragment of interest was tRNAleu-cox2 intergenic region. More than a half of the samples belongs to C12 haplotype, identical with C2d from Apis mellifera macedonica and Apis melllifera carnica. The second group has the same similarity on 94% of the fragment with Apis mellifera carnica C2c haplotype. There are two haplotypes, which can be associated with different subspecies of Apis melllifera included in C lineage. We discovered also two new haplotypes, C25 and C26 (GenBank acccession numbers: HQ215207, respectivelly HQ215208). One more conclusion has that Carpathian Mountains has not a natural obstacle in honeybees spreading during its natural adaptation process. |
|
|
|
|
|
|