Paschalis C. Harizanis

Ultrasound-assisted extraction of volatile compounds from citrus flowers and citrus honey

The volatile fraction of honey is believed to facilitate satisfactory discrimination between honeys of different botanical origin. A new methodology for extracting volatile compounds was developed, using n-pentane:diethylether organic solvent and a water bath with ultrasound assistance. Analysis of the extracts of four Citrus species’ flowers showed linalool to be the predominant compound (11.3% in lemon, 51.6% in orange, 80.6% in sour orange and 75.2% in tangerine). The extracts from citrus honey were predominated by an array of linalool derivatives (more than 80% of the total extract). (E)-2,6-dimethyl-2,7-octadiene-1,6-diol was the predominant compound (44.7%), while significant proportions of 2,6-dimethyl-3,7-octadiene-2,6-diol (15.4%) and (Z)-2,6-dimethyl-2,7-octadiene-1,6-diol (7.2%) were also present.

New Method for Pollen Identification by FT-IR Spectroscopy

A new methodology for identification of pollen was developed based on FT-IR spectroscopy. Pollen samples of twenty different plant species were collected and the diffuse reflectance infrared Fourier transform (DRIFTS) and KBr pellet spectra were recorded. Libraries of spectra were created. Spectra of unknown plant origin pollen were recorded and compared with those of the corresponding pollen library and the match value was measured automatically using the appropriate software (OMINC ver. 3.1). From the same pollen samples, microscopic slides were prepared and the photographs of the pollen grains were used as a second comparison method. Using light microscopy, the pollen identification is usually limited to the family or generic name, while FT-IR spectroscopy can distinguish species belonging to the same genus. This method is simple and fast, and when the DRIFTS technique is used the sample is not destroyed.

Allozyme Variability and Phylogenetic Relationships in Honey Bee (Hymenoptera: Apidae: Apis mellifera) Populations From Greece and Cyprus

Ten gene enzymic systems (α-GPDH, AO, MDH, ADH, LAP, SOD, ALP, ACPH, ME, and EST), corresponding to 12 genetic loci, were assayed from five Greek populations representing three subspecies of Apis mellifera, A. m. cecropia (Pthiotida, Kythira), A. m. macedonica (Macedonia), and the “Aegean race” of A. mellifera, which is supposed to be very similar to A. m. adami (Ikaria, Kasos), as well as a population from Cypus (A. m. cypria). ADH∗-1, ADH∗-2, and LAP∗ electrophoretic patterns discriminate the Cyprus population from the Greek populations. MDH∗-1, EST∗-3, SOD∗, ALP∗, and ME∗ loci were found to be polymorphic in almost all populations. The observed heterozygosity was found to range from 0.066 to 0.251. Allele frequencies of all loci were used to estimate Neis genetic distance, which was found to range between 0.011 and 0.413 among the populations studied. UPGMA and neighbor-joining phylogenetic trees obtained by genetic distance matrix methods, as well as a Wagner tree based on the discrete character parsimony method, support the hypothesis that the most distant population is that from Cyprus. Our allozymic data support A. m. cypria as a distinct subspecies, but there was no allozymic support for the distinction of the other subspecies existing in Greece.

Effects of Applaud on the growth of silkworm (Lepidoptera: Bombycidae).

Abstract An experiment was carried out to evaluate the effect of the insecticide Applaud (buprofezin 25% WP) on the silkworm Bombyx mori (L.). This insecticide belongs to the class of insect growth regulators (IGR). The larvae were fed on leaves treated with 3 different concentrations (0.5, 1, 2 g/liter) of Applaud on the 1st d of each instar. Analysis of data with the Tukey–Kramer test at 1% significant level revealed that mortality and larval duration did not differ among the treatments. On the contrary, the larval weight, which was estimated just before mounting (procedure during which the mature larva climbing on a branch or other material to spin the cocoon), differed among the treatments. Also, cocoon weight, shell weight, and cocoon sericin and fibroin content were different among the treatments, except the shell cocoon ratio. Maximum weight was observed in the controls and minimum in the last instar treatments. Our data suggest that supplementation of Applaud through food to larvae does not affect their mortality rate. On the contrary, it affects larval growth and cocoon parameters.

Diagnostic molecular markers discriminating Africanized honey bees from Greek and Cypriot honey bees (Apis mellifera, Hymenoptera: Apidae)

Summary Diagnostic patterns using PCR—RFLPs analysis of two mtDNA gene segments (16s rDNA and CO I) were shown to discriminate Africanized honey bees from Greek and Cypriot honey bees; high values of net nucleotide sequence divergence were observed among Africanized honey bees and the other populations studied. The tree obtained by UPGMA method ensured that the Africanized honey bee is discriminated from the honey bee populations from Greece and Cyprus. These results could be useful for the early detection of Africanized honey bees.

Monitoring of royal jelly protein degradation during storage using Fourier-transform infrared (FTIR) spectroscopy

Summary Royal jelly protein degradation was monitored by Fourier-transform infrared (FTIR) spectroscopy. The samples of royal jelly were stored at room temperature for 10 weeks at 4°C and -20°C for 31 weeks. The FT-IR spectra were then recorded and the ratio of peak area in 1545 (amide II) and 1656 cm−1 (amide I) was calculated. The ratio of peak areas associated with the degradation of proteins. It was observed that the ratio increased over time and with increasing storage temperature. The protein of royal jelly is maintained for three days at room temperature, seven weeks at 4°C and 21 weeks at -20°C.

The occurrence of Pealius mori (Takahashi), Pealius machili Takahashi and Paraleyrodes minei Iaccarino (Hemiptera: Aleyrodidae) infesting Morus alba L. in Greece

Summary Pealius machili (Takahashi, 1935), the mulberry whitefly Pealius mori (Takahashi, 1932) and the nesting whitefly Paraleyrodes minei (Iaccarino, 1990) were found infesting mulberry in Greece. The first species is reported for first time outside China, the second species was recorded for the first time in Greece, and the third species represents a new association. A brief description, illustrations and information on distribution and potential damage and control of each species are provided. The first results showed that nymphs were parasitized, although at a low rate. The reported species developed high infestation levels and thus may become major pests of mulberries in the eastern Mediterranean region.

Studying of quality parameters and organic contaminants in honey samples

Honey is valuable food for mankind since the ancient times. It was the only sweetener till the start of the industrial sugar mass production. As honey plays an important role in our nutrition and its positive effects on health is well known, it is very important to study the nutritional properties and the origin of different honey samples. The usually determined quality parameters of honey: pH values, water content, sugar content, acidity, HMF content, enzyme activity, pollen content, amino acid content, ash content, etc. It is also important to know the content of the organic contaminants in honey. A short time ago there were some quality problems with Hungarian and Greek honey in the European Union. A toxic material (para-dichlorobensene) was found in honey originated from Greece. The amount was higher than the allowable limit in the ELf. Therefore, it is necessary to build up a good and applicable traceability system for honey. During the past few years the traceability concept has become increasingly familiar in many sectors of the food industry. Traceability is an essential tool for ensuring both production and product quality. The opportunity to connect traceability with the whole documentation and control system represents an effective means for boosting the consumers perception of a foods safety and quality. In our work we have done, which quality parameters can be used for a good identification system. We have analyzed the following parameters of national and Greek honey types: mineral contents (trace elements), pH values, sugar content, acidity, HMF content, diastase activity. We have also analyzed the para-dichlorobensene in the honey samples. The samples were taken directly from Hungarian beekeepers (all professionals) and supermarkets (area of geographical origin unknown). We have measured also Greek honey. The samples were originated from some Greek islands, near Athens and from some Greek supermarkets. For the traceability it is necessary to know the following parameters: element content-free amino acids content-pollen content. Besides, it is important to analyze organic contaminants in honey.

A framework for electronic trading of hive products

Trade in honey faces high competition due to the high volume production and low prices offered by some countries. Honey production fluctuates year by year creating additional trading problems in the uniform provision of honey. Furthermore, the supply chain of hive products includes a number of importing and exporting activities among businesses worldwide. The Internet, fuelled by the phenomenal popularity of the World Wide Web, represents an increasingly important channel for retail commerce as well as business-to-business transactions. However, it is already clear that Web-based electronic commerce systems are successful only if they offer better ways for trading than the traditional supply chain. Current systems present a number of shortcomings due to a lack in efficient electronic brokerage. The aim of this paper is to propose a framework for Web-based electronic commerce systems for hive products, supported by efficient electronic information brokerage.

Analysis and Content of ATP in Spermatozoa of Honeybees

SummaryAdenosine triphosphate (ATP) concentration in sperm of honeybee (Apis mellifera) was determined by using a firefly-luciferase-luminescence method. Sperm from drone ejaculates contained 136·6 nmol ATP/109 cells. Sperm recovered from queen spermathecae contained 209·7 nmol ATP/109 cells. The ATP content of the spermathecal wall and fluid increased as queens became older. The methods described for ATP measurement of sperm extracts provide an alternative to the haemocytometer method for estimating concentrations of sperm from honeybees and possibly other insect species as well.