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Articles
by
Liviu Al. MARGHITAS |
Total Records (
9 ) for
Liviu Al. MARGHITAS |
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Cristian M. AURORI
,
Daniel S. DEZMIREAN
,
Liviu Al. MARGHITAS
and
Robin F.A. MORITZ
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During the last two decades, along the wellknown microsporidian Nosema apis, a new species N. ceranae is continuously spreading across the world where the western honeybee (Apis mellifera) is kept and bred by both professionals and hobbyists. Recent studies revealed that this species which jumped host from the asian honeybee (Apis cerana) to the more common western honeybee is present at least in the two American continents, Europe, Asia and Australia. Although the traditional standard diagnosis method is by visually detecting the Nosema spp. microspores by light microscopy, this approach cant make the difference between the two species. Thus, a much reliable, accurate and sensitive diagnosis method is by molecular techniques, like multiplex PCR, RFLP, Real Time qPCR or Microarray methods. These main molecular techniques are briefly presented as well, along with the differences between the two species at the amplified DNA fragments level. |
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Lavinia I. BARNUŢIU
,
Liviu Al. MARGHITAS
,
Daniel S. DEZMIREAN
,
Otilia BOBIS
,
Cristina M. MIHAI
and
CrenguNa PAVEL
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This paper contents a summary about antimicrobial compounds from royal jelly. Royal Jelly is a nutritive secretion produced by the hypopharyngeal and mandibular glands of worker bees; it is the main nutritional font of the queen honeybee and contains vitamins, carbohydrates, minerals and proteins. It possesses a number of pharmacological activities and is widely used in commercial medical products, health foods, and cosmetics in many countries. Peptides isolated from natural fonts are the object of several studies aimed at finding new molecules possessing antibacterial activity. |
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Otilia BOBIS
,
Liviu Al. MARGHITAS
,
Daniel S. DEZMIREAN
,
Flore CHIRILA
and
Robin F.A. MORITZ
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Different types of Romanian honeys were evaluated for their antioxidant and antibacterial activity. Total polyphenols, total flavonoids and two colorimetric methods for radical scavenging activity and the total antioxidant power showed different amounts of biologically active compounds in tested honey samples. Antibacterial activity was tested against Escherichia coli and Paenibacillus larvae, the first a model organism for bacteria and other a pathogenic bacterium causing American foul brood disease in Apis melliefra. Heather and honeydew honey had the highest content of total polyphenols (127.35 and 123.28 mgGAE/100 g and), while sunflower honey together with honeydew honey show the highest content of total flavonoids (64.25 and 65.98 mgQE/100 g honey). The most effective in antibacterial activity for P.larvae was found in sunflower honey whereas multifloral honey showed highest activity against E.coli. |
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Daniel S. DEZMIREAN
,
Liviu Al. MARGHITAS
,
Otilia BOBIS
,
Helge SCHLUNS
,
Cristian AURORI
,
Cristian COROIAN
,
Ellen SCHLUNS
,
Emilia FURDUI
,
Bogdan GHERMAN
,
Lavinia BARNUTIU
,
Cristina MIHAI
,
Ovidiu MAGHEAR
,
Laura STAN
and
Robin MORITZ
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The main objective of the project RoBeeTech is to create a high competence level
scientific center of bee biotechnology in Romania. The research directions of RoBeeTech are similar
to actual research interests of international teams in the field of bee pathology, bee products quality or
the genetic variability analysis of bees through modern biotechnologies. The three main research
directions involve the two research labs from USAMV Cluj-Napoca -APHIS (Laboratory for Quality
Control of Bee Products) and DIA (Laboratory for Bee Disease Diagnosis). The objectives of
RoBeeTech are focused on identification of genetic variability of bee colonies from Romania, the
study of bee-parasite-pesticide interaction and new control and treatment techniques based on
biologically active effect of bee products and secondary metabolites from plants. Until now bee
samples from over 80% of the country were collected, two progress reports and two repayment
documents were already delivered and 4 articles were published at international and national
conferences. |
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Bogdan I. GHERMAN
,
Liviu Al. MARGHITAS
,
Daniel S. DEZMIREAN
and
Robin F.A. Moritz
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This brief review is mend to present a better idea about the changes of honeybee
behavior when certain diseases occur. Lately, massive colony losses have been reported and previous
studies proved that not only single disease can destroy a colony, but multiple factors can have a huge
impact on the beekeeping industry. This brief review will help to understand better what is to do in the
near future in order to avoid losses of colonies of this social insect, the honeybee Apis mellifera. It is
very important to have alternatives to traditional treatments of diseases (many chemical substances
that we find in medical treatment have been forbidden not only in the EU, but also in many other
countries) and to get some answers in order to defeat the threat of industry breakdown due to poorer bee pollination. |
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Adela MOISE
,
Liviu Al. MARGHITAS
,
Daniel S. DEZMIREAN
,
Otilia BOBIS
and
Ovidiu MAGHEAR
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A theoretical study about the heather honey was done in order to establish its
main characteristics. This research represents a part of a large study regarding
the plant Calluna vulgaris and the honey obtained by bees harvesting
its nectar. Many bibliographical papers were studied in order to apply in laboratory
the appropriate methods for quality control and markers determination of heather
honey. The study focused especially on the papers regarding the physical-chemical
parameters, the melissopalynological exam, the mineral content and the chemical
markers of heather honey. |
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Crenguta I. I. PAVEL
,
Liviu Al. MARGHITAS
,
Daniel S. DEZMIREAN
,
Otilia BOBIS
,
Lavinia BARNUTIU
and
Agripina SAPCALIU
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Royal jelly is a secretion product of the cephalic glands of nurse bees that is very
sensible to the storage conditions. The aim of this study is to review the changes that occur in royal
jelly composition during storage and possible freshness parameters that have been studied. Evaluation
of coloration, viscosity, water-soluble protein fraction, enzyme glucose oxidase, furosine, 10-HDA
was proposed to assess the RJ freshness. Actually, royal jelly is one of the most studied bee products,
but further studies are necessary in order to establish an international standard of the product and its
freshness parameters. |
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Laura STAN
,
Liviu Al. MARGHITAS
and
Daniel S. DEZMIREAN
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Propolis samples were analyzed in order to determine the effect of collection
method over the general quality of this bee product. In this respect, during 2010-2011 were collected
12 propolis samples using a propolis collector and 12 samples using the hive tool. Propolis samples
were prepared as Ethanolic extracts (1%, w/v) and analyzed for phenolics composition (total
phenolics, flavones/flavonols, flavanones/dihydroflavonols). Wax content was also determined by
Soxhlet extraction. The results obtained proved that collection method has great influence over both
wax content and quantity of phenolic compounds from propolis. In conclusion propolis gathered by
means of a collector has lower amount of wax and higher amount of phenolics than propolis gathered
by hive tools. |
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Cristina ZAH
,
Liviu Al. MARGHITAS
,
Dan DEZMIREAN
,
Alexandra MATEI
and
Mihai BENTEA
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We know that the silkworms consume leaves in large quantities. The scope of the
research was observing their reaction to various additives for their food. In this experiment, we
administered mulberry leaves spray-coated with olive oil (0.66% of food mass) and filter paper soaked
in olive oil placed between leaves. The research was performed on four different silkworm hybrid
strands. Each hybrid was separated in 3 lots. The preliminary conclusions of the research were that
the olive oil is detrimental to the development of larvae, regardless of the method of administration. |
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