Encapsulated bee propolis powder: Drying process optimization and physicochemical characterization

Developing and Characterizing a Biocompatible Hydrogel Obtained by Cross-Linking Gelatin with Oxidized Sodium Alginate for Potential Biomedical Applications

The main goal of this research was to create biocompatible hydrogels using gelatin and a double cross-linking technique involving both covalent and ionic bonds to immobilize propolis. The covalent bonds were formed through Schiff base cross-links between protein-free amino groups (NH2) from the lysine residue and aldehyde groups (CHO) produced by oxidizing sodium alginate with NaIO4, while the ionic bonds were achieved using Mg2+ ions. Hydrogel films were obtained by varying the molar ratios of -CHO/-NH2 under different pH conditions (3.5 and 5.5). The presence of aldehyde groups in the oxidized sodium alginate (OSA) was confirmed using FTIR and NMR spectroscopy. The oxidation degree was monitored over 48 h, and the influence of temperature was examined. Results showed that higher -CHO/-NH2 molar ratios led to increased conversion index values of NH2 groups, and a decrease in swelling degree values was observed in mediums with pH values of 5.5 and 7.4. The encapsulation and release efficiency of propolis decreased with an increase in the hydrogel cross-linking degree. UV irradiation enhanced the antioxidant activity of both free and encapsulated propolis. These findings offer valuable insights for the biomedical and pharmaceutical fields into designing biocompatible hydrogels for propolis immobilization, with potential for controlled release.

The effect of nano/microparticles of bee pollen on the shelf life of high-fat cooked sausage during refrigerated storage

Sausage is susceptible to oxidative changes in lipids and microbial spoilage due to the presence of water, fat, protein, and vitamins. Bee pollen (BP) as a source of potential antioxidants and antibacterial compounds can effectively prevent lipid peroxidation and microbial spoilage in meat products. The aim of the present study was to investigate the antibacterial and antioxidant activities of BP and the effects of nano/microparticles of bee pollen extract (n/m BP) at a concentration of 125 and 250 mg/100 g meat on the oxidative stability and microbial growth of high-fat sausage during 30 days of storage at 4°C. The formation of BP particles in the nano/micro range was confirmed by scanning electron microscopy. High concentrations of total phenolic compounds (28.26 ± 0.10 mg GAE/g BP) with antioxidant activity (EC50 = 5.4 ± 0.07 mg/mL) were detected in BP. Based on the microdilution assay, the minimum inhibitory concentration of n/m BP for all test bacteria was 1000 (μg/mL) and the minimum bactericidal concentration of n/m BP was 2000 (μg/mL) for Staphylococcus aureus and Bacillus cereus and 4000 (μg/mL) for Escherichia coli and Pseudomonas aeruginosa. The n/m BP treatment (250 mg/100 g meat) showed a higher pH value (p < .05) and lower TBARS values (p < .05) than the ascorbic acid treatment (100 mg/100 g meat) and the control during the storage period. The microbial analysis showed that the addition of n/m BP led to a significant decrease (p < .05) in the total bacterial count, coliforms, S. aureus, and fungal population compared to the other samples. The results show that the addition of n/m BP (125 mg/100 g) can improve the texture, taste, and overall acceptability of the sausage compared to the control sample. In conclusion, this study suggests that BP can replace synthetic antioxidants in high-fat sausages at the nano/microparticle level.

Potential application of bee products in food industry: An exploratory review

Over the past eight years, bee products such as wax, honey, propolis, and pollen have generated intense curiosity about their potential food uses; to explore these possibilities, this review examines the nutritional benefits and notable characteristics of each product related to the food industry. While all offer distinct advantages, there are challenges to overcome, including the risk of honey contamination. Indeed, honey has excellent potential as a healthier alternative to sugar, while propolis's remarkable antibacterial and antioxidant properties can be enhanced through microencapsulation. Pollen is a versatile food with multiple applications in various products. In addition, the addition of beeswax to oleogels and its use as a coating demonstrate significant improvements in the quality and preservation of environmentally sustainable foods over time. This study demonstrates that bee products and apitherapy are essential for sustainable future food and innovative medical treatments.

Applications of propolis encapsulation in food products

Propolis has beneficial health properties attributed to of phenolic compounds. However, its application is limited. Thus, encapsulation protects the bioactive compounds of propolis from degradation, allowing their release under controlled and specific conditions and increasing their solubility. In addition to protecting flavonoids, encapsulation also minimises the undesirable characteristics of propolis, such as strong odour. We brought attention to the high antioxidant and antimicrobial activities of encapsulated propolis, and its maintained biological activity enables more uses in different areas. Encapsulated propolis can be applied in food products as an ingredient. This review describes recent advances in improving the bioactivity of propolis extracts by using encapsulation techniques, and biopolymer research strategies, focusing on applications in food products. Encapsulated propolis has a promising market perspective due to the industrial and scientific-technological advancement, the increase in the amount of research, the improvement of propolis extraction techniques, and the need of consumers for innovative products.

Plant-Derived Nanocellulose with Antibacterial Activity for Wound Healing Dressing

The medical sector is one of the biggest consumers of single-use materials, and while the insurance of sterile media is non-negotiable, the environmental aspect is a chronic problem. Nanocellulose (NC) is one of the safest and most promising materials that can be used in medical applications due to its valuable properties like biocompatibility and biodegradability, along with its good mechanical properties and high water uptake capacity. However, NC has no bactericidal activity, which is a critical need for the effective prevention of infections in chronic diabetic wound dressing applications. Therefore, in this work, a natural product, propolis extract (PE), was used as an antibacterial agent, in different amounts, together with NC to obtain sponge-like structures (NC/PE). The scanning electron microscope (SEM) images showed well-impregnated cellulose fibers and a more compact structure with the addition of PE. According to the thermogravimetric analysis (TGA), the samples containing PE underwent thermal degradation before the unmodified NC due to the presence of volatile compounds in the extract. However, the peak degradation temperature in the first derivative thermogravimetric curves was higher for all the sponges containing PE when compared to the unmodified NC. The antibacterial efficacy of the samples was tested against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli, as well as on two clinically resistant isolates. The samples completely inhibited the development of Staphylococcus aureus, and Pseudomonas aeruginosa was partially inhibited, while Escherichia coli was resistant to the PE action. Considering the physical and biological properties along with the environmental and economic benefits, the development of an NC/PE wound dressing seems promising.

Development and Characterization of High-Absorption Microencapsulated Organic Propolis EPP-AF® Extract (i-CAPs)

The demand for organic and functional food continues to increase yearly. Among the available functional foods, propolis is a bee product that has various beneficial properties, including antimicrobial, antioxidant, and anti-inflammatory activities. However, it generally is only available in ethanol solution, which has poor bioavailability, as it is relatively insoluble in water. The use of such ethanol extracts is often objectionable because of the alcohol content and because they have a strong and striking taste. Development of alternatives that can efficiently and safely increase solubility in water, and that meet organic production specifications, has been a challenge. To address these concerns, microcapsules were developed using spray-dryer technology from an emulsion based on EPP-AF® propolis and gum arabic (i-CAPS). These propolis-loaded microcapsules were characterized using FT-IR, SEM, TGA, HPLC, and spectrophotometric techniques, along with determination of antimicrobial, antioxidant, antitumor, anti-inflammatory, and antihypercholesterolemic activities, as well as permeability in in vitro models. The production system resulted in microcapsules with a spherical shape and an encapsulation efficiency of 93.7 ± 0.7%. They had IC50s of 2.654 ± 0.062 and 7.342 ± 0.058 µg/mL by FRAP and DPPH antioxidant methods, respectively. The EPP-AF® i-CAPS also had superior antimicrobial activity against Gram-positive bacteria. Antitumor activity was calculated based on the concentration that inhibited 50% of growth of AGS, Caco-2, and MCF-7 cell strains, giving results of 154.0 ± 1.0, 117 ± 1.0, and 271.0 ± 25 µg/mL, respectively. The microcapsule presentation reduced the permeation of cholesterol by 53.7%, demonstrating antihypercholesterolemic activity, and it improved the permeability of p-coumaric acid and artepillin C. The IC50 for NO production in RAW 264.7 cells was 59.0 ± 0.1 µg/mL. These findings demonstrate the potential of this new propolis product as a food and pharmaceutical ingredient, though additional studies are recommended to validate the safety of proposed dosages.

High-shear wet agglomeration process for enriching cornstarch with curcumin and vitamin D3 co-loaded lyophilized liposomes

Curcumin and vitamin D₃ are bioactive molecules of great importance for the food industry. However, their low stability in several processing conditions hampers their proper incorporation into powdered food formulations. This study proposes the enrichment of a common raw material (cornstarch) with curcumin and vitamin D₃ by using high-shear wet agglomeration. The bioactives were initially encapsulated into liposome dispersions and then subjected to lyophilization. The resulting dried vesicles were later incorporated into cornstarch by wet agglomeration using maltodextrin as the binder solution. The phospholipid content and the amount of added liposomes were evaluated to characterize the enriched cornstarch samples. The lyophilized vesicles showed a high retention rate of 99 % for curcumin and vitamin D₃, while the enriched cornstarch samples retained above 96 % (curcumin) and 98 % (vitamin D₃) after 30 days of controlled storage. All in all, the presence of dried liposomes improved the flowability and delayed retrogradation phenomenon in agglomerated cornstarch. Therefore, this study introduced a novel and reliable method of incorporating hydrophobic and thermosensitive molecules into powdered food formulations by using readily available materials and a straightforward high-shear wet agglomeration process.

Microencapsulation of Propolis and Honey Using Mixtures of Maltodextrin/Tara Gum and Modified Native Potato Starch/Tara Gum

Ethanolic extracts of propolis and bee honey contain substances beneficial to human health. Mixtures of wall materials were compared in spray-drying microencapsulation of ethanolic extracts of propolis and bee honey rich in bioactive compounds. Maltodextrin and tara gum were used to obtain microencapsulates A, and modified native potato starch and tara gum were used for microencapsulates B. High values of phenolic compounds, flavonoids, and antioxidant capacity were obtained in microcapsules A and B, and the results obtained in terms of encapsulation efficiency, yield, hygroscopicity, solubility, moisture, Aw, bulk density, and color were typical of the spray-drying process. On the other hand, spherical and elliptical microparticles of sizes between 7.83 and 53.7 µm with light and medium stability were observed. Thermogravimetric properties were similar in both microencapsulates; total organic carbon, SEM-EDS, and FTIR analyses corroborated the encapsulation. X-ray diffractogram exhibited amorphous structures, and the release kinetics of phenolic compounds presented high values from 8.13 to 12.58 mg GAE/g between 7 and 13 h. Finally, modified potato starch is a better encapsulant than maltodextrin because it has better core protection and controlled release of the encapsulated bioactive compounds.

Obtaining and Characterizing Andean Multi-Floral Propolis Nanoencapsulates in Polymeric Matrices

Propolis is a substance with significant anti-inflammatory, anticancer, and antiviral activity, which could be used more efficiently at the nano level as an additive in the food industry. The aim was to obtain and characterize nanoencapsulated multi-floral propolis from the agro-ecological region of Apurimac, Peru. For nanoencapsulation, 5% ethanolic extracts propolis with 0.3% gum arabic and 30% maltodextrin were prepared. Then, the mixtures were dried by nano spraying at 120 °C using the smallest nebulizer. The flavonoid content was between 1.81 and 6.66 mg quercetin/g, the phenolic compounds were between 1.76 and 6.13 mg GAE/g, and a high antioxidant capacity was observed. The results of moisture, water activity, bulk density, color, hygroscopicity, solubility, yield, and encapsulation efficiency were typical of the nano spray drying process. The total organic carbon content was around 24%, heterogeneous spherical particles were observed at nanometer level (between 11.1 and 562.6 nm), with different behaviors in colloidal solution, the thermal gravimetric properties were similar in all the encapsulates, the FTIR and EDS analysis confirmed the encapsulation and the X-ray diffraction showed amorphous characteristics in the obtained material; stability and phenolic compound release studies indicated high values of 8.25–12.50 mg GAE/g between 8 and 12 h, the principal component analysis confirmed that the flora, altitude, and climate of the propolis location influenced the content of bioactive compounds, antioxidant capacity, and other properties studied. The nanoencapsulate from the district of Huancaray was the one with the best results, allowing its future use as a natural ingredient in functional foods. Nevertheless, technological, sensory, and economic studies should still be carried out.