Honey is known for its content of biomolecules, such as enzymes. The enzymes of honey originate from bees, plant nectars, secretions or excretions of plant-sucking insects, or from microorganisms such as yeasts. Honey can be characterized by enzyme-catalyzed and non-enzymatic reactions. Notable examples of enzyme-catalyzed reactions are the production of hydrogen peroxide through glucose oxidase activity and the conversion of hydrogen peroxide to water and oxygen by catalase enzymes. Production of hydroxymethylfurfural (HMF) from glucose or fructose is an example of non-enzymatic reactions in honey.

Acacia honey is characterized by high nutritional, antioxidant, antibacterial and immuno-modulatory values. This work investigated the presence of short and cyclic peptides in Acacia and Ziziphus honey samples. Acacia honey samples (Acacia tortilis and Acacia hamulosa) and three Ziziphus honeys (Ziziphus spina-christi) were screened for their short and cyclic peptide contents using the LC-MS and the chemical structure databases. Moreover, the total protein content was determined using the Bradford method. The A. tortilis honey contained three short peptides; HWCC, DSST, and ECH, and the A. hamulosa honey sample contained five short peptides and one cyclic peptide. The short peptides of the A. hamulosa honey were Ac-GMGHG-OH (Ac-MGGHG-OH), Boc-R(Aloc)2-C(Pal)-OH, H-C (1)-NEt2·H-C (1)-NEt2, APAP (AAPP), and GAFQ (deamino-2-pyrid-4-yl-glycyl-dl-alanyl-dl-norvalyl-dl-asparagine). The cyclic peptide of the A. hamulosa honey was cyclo[Aad-RGD-d-F] (cyclo[Aad-Arg-Gly-Asp-d-Phe]). The Ziziphus honey was characterized by the presence of either Almiramide B or Auristatin-6-AQ. A. tortilis, A. hamulosa, and Ziziphus honeys are characterized by the presence of short and cyclic peptides which may contribute to their medicinal values.

The antibacterial, anticancer, and wound-healing effects of honey can vary according to the type, geographical region, honey bee species, and source of the flowers. Nanotechnology is an innovative and emerging field of science with an enormous potential role in medical, cosmetics, and industrial usages globally. Metal nanoparticles that derived from silver and range between 1 nm and 100 nm in size are called silver nanoparticles (AgNPs). Much advanced research AgNPs has been conducted due to their potential antibacterial and anticancer activity, chemical stability, and ease of synthesis. The purpose of the present study was to explore the physicochemical properties of honey and the potential to use forest honey to synthesize AgNPs as well as to appraise the nanoparticles’ antimicrobial and anticancer effects. Here, we used three different percentages of forest honey (20%, 40%, and 80%) as biogenic mediators to synthesize AgNPs at room temperature. The development of AgNPs was confirmed by color change (to the naked eye) and ultraviolet-visible spectroscopy studies, respectively. The absorbance peak obtained between 464 to 4720 nm validated both the surface plasmon resonance (SPR) band and the formation of AgNPs. Regarding the sugar profile, the contents of maltose and glucose were lower than the content of fructose. In addition, the results showed that the SPR band of AgNPs increased as the percentage of forest honey increased due to the elevation of the concentration of the bio-reducing agent. A bacterial growth kinetic assay indicated the strong antibacterial efficacy of honey with silver nanoparticles against each tested bacterial strain. Honey with nanotherapy was the most effective against hepatocellular carcinoma (HepG2) and colon cancer (HCT 116) cells, with IC50s of 23.9 and 27.4 µg/mL, respectively, while being less effective against breast adenocarcinoma cells (MCF-7), with an IC50 of 32.5 µg/mL.

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The activity of honey enzymes are affected by floral and geographical origins, climate conditions, honeybee species, health and nutrition. This article investigated the effect of floral and geographical origins on the activity of glucose oxidase (GOx) and catalase (CAT) enzymes in honey samples from the southwestern region of Saudi Arabia. Moreover, the moisture, total sugars, pH and conductivity were measured as quality parameters. The floral origin of the honey samples was determined microscopically while the quality parameters were measured according to the methods of international honey commission. The activity of the honey enzyme was determined following the instructions of the Megazyme International kits. The obtained results were statistically analyzed by the statistical Package for Social Sciences (SPSS, v.20). The GOx activity of the Acacia, Ziziphus and polyfloral honey samples of the Asir region were (5.19 ± 2.33 U/g), (4.01 ± 1.17 U/g) and (5.69 ± 1.67 U/g), respectively. The Acacia, Ziziphus and polyfloral honey samples from the Jazan region had GOx activities of (6.85 ± 0.47 U/g), (10.48 ± 9.22 U/g) and (5.31 ± 2.7 U/g), respectively. The geographical origin significantly affected the GOx activity of Ziziphus honey (p-value = 0.005) and the GOx activity of the Ziziphus honey was significantly more than that of the polyfloral honey of the Jazan region (p-value = 0.009). With regard to the CAT activity in Asir region honey samples, the mean values of the Acacia, Ziziphus and polyfloral honeys were (2.89 ± 1.08 U/g), (3.58 ± 1.59 U/g) and (2.84 ± 1.24 U/g), respectively. The mean values of the CAT activity in the Jazan honey samples were Acacia (4.35 ± 1.01 U/g), Ziziphus (3.94 ± 0.04 U/g) and polyfloral (3.43 ± 0.67 U/g). The geographical origin significantly affected the CAT activity in Acacia honey (p-value = 0.014). The geographical and floral origins had significant effects on the activity of the honey GOx and CAT enzymes.