Antibacterial drugs are used worldwide for the control of American and, less often, European foulbrood. Their administration is mostly uncontrolled and applied without approved protocols and instructions for use as well as precautionary recommendations. Consequently, this practice is responsible for the contamination of beehive products and contributes to the problem of food safety. According to this situation, 4672 analyses were carried out on 5303 honeys collected from 2001 to 2007. These samples were investigated for antibacterial residues of tetracyclines, sulphonamides, streptomycin, chloramphenicol and tylosin. Honeys were classified according to their origin: imported honey and honey from the Italian market. In the last group (only for samples collected from 2001 to 2004), another type of honey was distinguished: that of local honey. A total of 6.3% of all samples were positive for the antibacterial drugs analysed; in particular, 6.8% of imported honeys and 6.1% of honeys on the Italian market. Only 1.7% of local honey had antibacterial residues. These results are indicative of a rather frequent presence of antibacterial drug residues in both Italian and imported honeys. Furthermore, the data showed that among the active substances analysed, sulphonamides are the most used antibacterial substance followed by tetracyclines, streptomycin, tylosin, and chloramphenicol. Finally, a continuous monitoring programme is needed, accompanied by an education programme to beekeepers on proper hive management.

The use of antibiotic drugs in the control of American foul brood (AFB) and other honeybee diseases , is still a common practice. Two type of drugs, tetracyclines (TCs) and sulphonamides (SPs), are frequently used, although during the last years other antibiotics like chloramphenicol (CAF), streptomycin (ST) and nitrofuran have been recognised to be administered to colonies by beekeepers. The use of these drugs is illegal because no maximum residue limits (MRL’s) have been established, whereas only OTC is approved in USA. Since antibiotics are active against the vegetative form of bacteria, in the case of AFB the drug administration to infected colonies suppress bacterial replication, but the symptoms readily reappear once the drug is discontinued (Ratnieks, 1992). As a consequence, beekeepers have to repeat drug treatments as preventive method to control of the diseases. This uncontrolled drugs administration determines both an increase of resistant bacteria and the contamination of honey. According to Council Directive 96/23/EC laying down measures to monitor certain substances and residues thereof in live animals and animals residues, honey imported from third countries has to be investigated for antibacterial substances. Honey samples analysed for antibiotics residues from 2001 to 2003 were considered in our laboratory.

The changes in quality of royal jelly stored at 50°C for 2h 30', 5h, 7h 30' and at 37°C for 7 and 15 days were investigated. Browning, pH, acidity, enzimatic activity (diastase, invertase, glucose-oxidase) as quality indexes were analized. During the ageing the colour of royal jelly changed: the browning reaction increased proportionally to both temperature and storage time. pH and acidity values didn't change. Glucose-oxidase, the only enzyme detected in royal jelly, was subjected to an exponential decrease: the same value of glucose-oxidase in the sample stored at 37°C for 7 days was reached after 7 hours at 50°C.

The changes in quality of royal jelly stored at 50 degrees C for 2h 30', 5h, 7h 30' and at 37 degrees 0 for 7 and 15 days were investigated. Browning, pH, acidity, enzymatic activity (diastase, invertase, glucose-oxidase) as quality indexes were analyzed. During the ageing the colour of royal jelly changed: the browning reaction increased proportionally to both temperature and storage time. pH and acidity values didn't change. Glucose-oxidase, the only enzyme detected in royal jelly, was subjected to an exponential decrease: the same value of glucose-oxidase in the sample stored at 37 degrees C for 7 days was reached after 7 hours at 50 degrees C.