Study of the quality and antibacterial activity of some honeys

Honey is a sweet substance that bees make from the nectar of owers or honeydew, having varying chemical composition and properties. The aim of this research is screening the antimicrobial effects of eight different honey samples from Algeria . Samples of honey were collected from different areas of Tizi-Ouzou. Samples of honey have been studied for their physicochemical and pollen parameters and their antimicrobial effect on Escherichia coli, Staphylococcus aureus , Pseudomonas aeruginosa , Staphylococs epidermitidis, Listeria inocua Enteococcus fecalis Bacillus cerius .The analyzes carried out on the 8 samples of honey reveal a water content of 16.80 to 22%, an acidic pH of 3.70 to 4.04, an electrical conductivity of 0.26 to 0.85 × 10-4 S / cm and a hydroxymethylfurfural level between 16 to 38.03 mg / kg. These results show that these samples are of good quality compared to international standards. The pollen analysis allowed the identication of different botanical families. According to our results all the honey samples have effectively high antibacterial activity against studded strains. by the H8 with an inhibition zone of 17 mm, for Staphylococcus aureus the maximum inhibition diameter was observed with the H1 (16 mm).The zone of maximum inhibition for the Pseudomonas aeruginosa strain was observed with H8 (22mm). From the results of the evaluation of the antimicrobial activity obtained, it can be seen that all the bacterial strains tested are sensitive to the inhibitory action of samples honey with more or less pronounced effects.


Introduction
Honey is sweet, viscous syrup produced by the honey bee (Apis mellifera). It is probably the rst natural sweetener ever discovered, and is currently used as a nutritious food supplement and medicinal agent (Olas 2020  The impact of infectious diseases continues to grow around the world. This is usually due to the phenomenon of antibiotic resistance. For this reason, recent studies are interested in the therapeutic virtues of certain natural products which do not generally have side effects. Honey is one of these most coveted products because of its inhibitory and therapeutic properties, honey is subject to a number of speculations as to its origin and its physico-chemical qualities Algerian consumer does not manage to distinguish between an authentic product and another falsi ed because of the absence of o cial structures that control the quality of local products.These allow us to identify the properties of the different honeys harvested in several regions of Tiziouzou .

Honey samples
Our study focused on 8 samples of honey, of different geographical origins distributed in the wilaya of Tizi-Ouzou (Sidi naamane, Tizi rached, Freha and Azeffoun) code respectively);A code has been assigned to each sample, in order to facilitate their handling during the various analyzes in the laboratory. H1 to H8 Assumed oral origin : Eucalyptus for H1, Orange tree for H2, acacia for H5 ,lavender for H6 ,all owers for other samples .The honey samples were collected in sterile 50mL falcon tubes and stored in the freezer at -20°C until analysis (water content, pH and free acidity, electrical conductivity; Hydroxy-Methyl-Furfural or simply HMF) and pollen analyzes.
The evaluation of the antimicrobial activity of honey was carried out by diffusion through discs in the presence of the microbial strains. Provided by the microbiology laboratory of the University of Hassiba Ben bouali Chlef: Staphylococcus aureus (ATCC29213) ,Pseudomonas aeruginosa, Escherichia coli (ATCC25922), Staphylococs epidermitidis, Listeria inocua Enteococcus fecalis and Bacillus cerius The choice of these strains is based on their wall differences (Gram + and Gram-), as well as their presence in the digestive tract or on the skin.

Antibacterial Activity
Antibacterial activity was tested against a panel pathogenic microorganisms .The disc diffusion method, known as the Kirby-Bauer method, was used to determine the antibacterial activities of samples honey

phenols and avonoids evaluation
The total phenolic content was estimated using the spectrometric method of Folin-Ciocalteu' as described by

Antioxidant activity
The antioxidant activity of the extracts was evaluated based on hydrogen-donating or radical-scavenging ability using the stable free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). An amount (0.1 mL) of phenolic extracts was added to 3 mL of 0.04% methanolic solution of DPPH The mixture was mixed thoroughly and incubated in dark at room temperature for 60 min. The decrease in absorbance was then measured at 517 nm, against methanol as a blank.

Results And Discussion
The most important physico-chemical parameters were measured for the honey samples, namely: water content, electrical conductivity, pH, free acidity and 5-hydroxyméthylfurfural (HMF), and the results are summarized in Table 1. and which does not exceed 20%; This con rms that the risk of fermentation is very low in these samples.
According to Gonnet (1982), honeys are in good conservation because they represent water contents of less than 18%.
Unlike the H4 sample collected in the Azeffoun region which represents the highest water content (22%  (Acquarone, 2007).The measurement of electrical conductivity is very important because it makes it easy to distinguish honeydew honeys from those of nectar-bearing origin, the former having a higher conductivity than the latter (Bogdanov et al. 1999).

pH
The pH is a measure which allows the determination of the oral origin of honey, of which the honeys from nectar have a pH between 3.5 and 4.5, whereas those from miellas are between 5 and 5.5 (Gonnet 1982

Hydroxymethylfurfural (Hmf) Rate
The presence of HMF in honey is indicative of more or less advanced degradation of the product, it therefore provides information on the state of freshness of honey. The HMF rate must remain very low for a guarantee of quality and proof of good conservation of the product. (Thrasyvoulou 1986) According to Bogdanov et al. (2004), the amount of HMF tolerated in honey should always be very low and not exceed 40 mg / kg.
The quantitative results of HMF presented in (

Pollen Analyzes
The pollen analysis is mainly done for the purpose of con rming the oral source of the honeys tested. The results are summarized in Figure 1 Pollen analysis of sample H1 shows the presence of fourteen different taxa of nectar-bearing pollen with a total of 4850 grains.
According to the percentages of the pollen families, this honey is a multi oral containing eucalyptus, because usually eucalyptus honeys are over-represented and can only carry the mention "eucalyptus honey" from 90% of eucalyptus pollen ) (Bobis et al. 2020).
Observation of sample H3 shows the presence of sixteen different taxa of nectar-bearing pollen with negligible traces of honeydew, with a total of 5740 grains.
According to the percentages of the pollen families, this honey is a Hedysarum mono oral. (Makhlou et al. 2015) .
The observed slide of sample H4 is very rich in pollen, it presents a thick protein lm with a mineral residue

Evaluation Of Antimicrobial Activity
The results of antimicrobial activity as shown in Table 2 show that all the strains studied are more or less

Conclusion
The different parameters studied show that all the honey samples comply with the standards proposed by the Codex Alimentarius Commission, that most of them are fresh honeys, according to their HMF content. But also that they are not falsi ed following the results of the pollen analysis. Regarding the antibacterial activity, the present study con rms that each honey analyzed exerts inhibition for the different tested bacteria.

Declarations
• Consent for publication: Authors Consent for all data publication • Availability of data and materials: All data are availaibils

• Competing interests
The authors declare that they have no con icts of interest • Abdelhamid belhadj benziane is currently works in civil protection . He has published several meaningful research and review article, of international repute journal and has presented his papers in many national and international conferences.
• Naima smaili is currently working as Co-Investigator on different Interdisciplinary research projects. The major research areas are investigating the therapeutic potential of different medicinal plant extracts.