Characterisation of peppermint (Mentha piperita L.) essential oil encapsulates

Microencapsulation to Harness the Antimicrobial Potential of Essential Oils and Their Applicability in Dairy Products: A Comprehensive Review of the Literature

This literature review explores cutting-edge microencapsulation techniques designed to enhance the antimicrobial efficacy of essential oils in dairy products. As consumer demand for natural preservatives rises, understanding the latest advancements in microencapsulation becomes crucial for improving the shelf life and safety of these products. The bibliometric analysis utilized in this review highlighted a large number of documents published on this topic in relation to the following keywords: essential oils, AND antimicrobials, AND dairy products, OR microencapsulation. The documents published in the last 11 years, between 2013 and 2023, showed a diversity of authors and countries researching this topic and the keywords commonly used. However, in the literature consulted, no study was identified that was based on bibliometric analysis and that critically evaluated the microencapsulation of essential oils and their antimicrobial potential in dairy products. This review synthesizes findings from diverse studies, shedding light on the various encapsulation methods employed and their impact on preserving the quality of dairy goods. Additionally, it discusses the potential applications and challenges associated with implementation in the dairy industry. This comprehensive analysis aims to provide valuable insights for researchers, food scientists, and industry professionals seeking to optimize the use of essential oils with antimicrobial properties in dairy formulations.

A dataset of microstructure features of electro-hydrodynamic assisted 5-fluorouracil-grafted alginate microbeads and physicochemical properties for effective colon targeted carriers drug delivery

5-Fluorouracil (5-FU) has been the primary drug used in chemotherapy for colorectal carcinoma, and localizing the drug would be effective in avoiding its side effects and improving therapeutic outcomes. One approach to achieve this is by encapsulating the drug in microbeads. Alginate microbeads, in particular, exhibit promising pH-sensitive properties, making them an attractive option for colon targeting. Thus, the main aim of this study is to formulate and characterize 5-FU-encapsulated alginate microbeads as a pH-sensitive drug delivery system for controlled release in the gastrointestinal tract. In this study, the alginate microbeads encapsulating 5-FU was manufactured using electrospray methods. This method offers the advantages of promoting the formulation of uniformly small-sized microbeads with improved performance in terms of swelling and diffusion rates. The size and shape of the 5-FU microbeads are 394.23 ± 3.077 µm and have a spherical factor of 0.026 ± 0.022, respectively, which are considered acceptable and indicative of a spherical shape. The microbeads' encapsulation efficiency was found to be 69.65 ± 0.18%, which is considered high in comparison to other literature. The attenuated total reflectance - Fourier transform infrared spectroscopy (ATR-FTIR) data confirmed the complexation of sodium alginate with calcium ions, along with the encapsulation of 5-FU in the microbeads matrix. The 5-FU microbeads displayed pH-dependent swelling, exhibiting less swelling in simulated gastric fluid (SGF) than in simulated intestinal fluid (SIF). Additionally, the release of 5-FU from the microbeads is pH-dependent, with the cumulative percentage drug release being higher in simulated intestinal fluid than in SGF. The data indicate that the 5-FU microbeads can be utilized for the delivery of 5-FU in colon-targeted therapy, potentially leading to improved tumor treatment.

A Comprehensive Study on Peppermint Oil and Cinnamon Oil as Nanoemulsion: Preparation, Stability, Cytotoxicity, Antimicrobial, Antifungal, and Antioxidant Activity

BACKGROUND

Recent studies have shown that nanoemulsions prepared with essential oils have significant antimicrobial potential against multidrug-resistant pathogens due to increased chemical stability. Nanoemulsion also promotes controlled and sustained release, which increases their bioavailability and efficacy against multidrug-resistant bacteria.

OBJECTIVE

This study aimed to investigate the antimicrobial, antifungal, antioxidant, and cytotoxicity properties of cinnamon essential oil and peppermint essential oil as nanoemulsions compared to pure forms. For this purpose, analyses of the selected stable nanoemulsions were carried out.

METHOD

The droplet sizes and zeta potentials of peppermint essential oil nanoemulsions and cinnamon essential oil nanoemulsions were found to be 154.6±1.42 nm and -17.1±0.68 mV and 200.3±4.71 nm and -20.0±0.81 mV, respectively. Although the amount of essential oil used in nanoemulsions was 25% w/w, antioxidant and antimicrobial activities were found to be more effective compared to pure essential oils.

RESULTS

In cytotoxicity studies on the 3T3 cell line, both essential oil nanoemulsions showed higher cell viability than pure essential oils. At the same time, cinnamon essential oil nanoemulsions exhibited a higher antioxidant property than peppermint essential oil nanoemulsions and showed superiority in the antimicrobial susceptibility test conducted against four bacteria and two fungi. Cell viability tests determined that cinnamon essential oil nanoemulsions showed considerably higher cell viability compared to pure cinnamon essential oil.

CONCLUSION

These findings indicated that the prepared nanoemulsions in the current study might positively influence the dosing regimen and clinical outcomes of antibiotic therapy.

Essential Oils and Their Combination with Lactic Acid Bacteria and Bacteriocins to Improve the Safety and Shelf Life of Foods: A Review

The use of plant extracts (e.g., essential oils and their active compounds) represents an interesting alternative to chemical additives and preservatives applied to delay the alteration and oxidation of foods during their storage. Essential oils (EO) are nowadays considered valuable sources of food preservatives as they provide a healthier alternative to synthetic chemicals while serving the same purpose without affecting food quality parameters. The natural antimicrobial molecules found in medicinal plants represent a possible solution against drug-resistant bacteria, which represent a global health problem, especially for foodborne infections. Several solutions related to their application on food have been described, such as incorporation in active packaging or edible film and direct encapsulation. However, the use of bioactive concentrations of plant derivatives may negatively impact the sensorial characteristics of the final product, and to solve this problem, their application has been proposed in combination with other hurdles, including biocontrol agents. Biocontrol agents are microbial cultures capable of producing natural antimicrobials, including bacteriocins, organic acids, volatile organic compounds, and hydrolytic enzymes. The major effect of bacteriocins or bacteriocin-producing LAB (lactic acid bacteria) on food is obtained when their use is combined with other preservation methods. The combined use of EOs and biocontrol agents in fruit and vegetables, meat, and dairy products is becoming more and more important due to growing concerns about potentially dangerous and toxic synthetic additives. The combination of these two hurdles can improve the safety and shelf life (inactivation of spoilage or pathogenic microorganisms) of the final products while maintaining or stabilizing their sensory and nutritional quality. This review critically describes and collects the most updated works regarding the application of EOs in different food sectors and their combination with biocontrol agents and bacteriocins.

Optimized Peppermint Essential Oil Microcapsules Loaded into Gelatin-Based Cryogels with Enhanced Antimicrobial Activity

In this study, chitosan (Chi) was used to microencapsulate peppermint essential oil (PEO). A novel gelatin-based cryogel loaded with PEO microcapsules was further developed and characterized for potential applications. Four different cryogel systems were designed, and the morphological, molecular, physical and antibacterial properties were investigated. Additionally, the antimicrobial properties of PEO, alone and microcapsulated, incorporated into the cryogel network were evaluated. The observed gel structure of cryogels exhibited a highly porous morphology in the microcapsules. The highest values of the equilibrium swelling ratio were acquired for the GelCryo-ChiCap and GelCryo-PEO@ChiCap samples. The contact angle GelCryo-PEO@ChiCap sample was lower than the control (GelCryo) due to the water repelling of the essential oil. It has been found that the incorporation of encapsulated PEO into the cryogels would be more advantageous compared to its direct addition. Moreover, GelCryo-PEO@ChiCap cryogels showed the strongest antibacterial activities, especially against Staphylococcus aureus (Gram-positive bacteria) and Escherichia coli (Gram-negative bacteria). The system that was developed showed promising results, indicating an improved antibacterial efficacy and enhanced structural properties due to the presence of microcapsules. These findings suggest that the system may be an appropriate candidate for various applications, including, but not limited to, drug release, tissue engineering, and food packaging. Finally, this system demonstrates a strategy to stabilize the releasing of the volatile compounds for creating successful results.

Encapsulation of Heracleum persicum essential oil in chitosan nanoparticles and its application in yogurt

Heracleum percicum essential oil (HEO) at various levels was encapsulated in chitosan nanoparticles and its potential application in yogurt was investigated. The values obtained for encapsulation efficiency, loading capacity, mean particle size, and zeta potential of nanoparticles were 39.12-70.22%, 9.14-14.26%, 201.23-336.17 nm, and + 20.19-46.37 mV, respectively. The nanoparticles had spherical shape with some holes as a result of drying process. In vitro release studies in acidic solution and phosphate buffer solution indicated an initial burst effect followed by slow release with higher release rate in acidic medium. Results of antibacterial activity revealed that Staphylococcus aureus and Salmonella typhimurium with inhibition zones of 21.04-38.10 and 9.39-20.56 mm were the most sensitive and resistant bacteria to HEO, respectively. Incorporation of encapsulated HEO into yogurt decreased pH and increased titratable acidity due to stimulation of starters' activity. Interaction of nanoparticles with proteins decreased syneresis in yogurt. Regarding antioxidant activity, a higher value was observed in yogurt containing encapsulated HEO after 14 days of storage due to degradation and release of essential oil from nanoparticles. In conclusion, application of HEO nanoparticles in yogurt could be a promising approach for development of functional food products such as yogurt with enhanced antioxidant properties.

Aromatherapeutic and Antibacterial Properties of Cotton Materials Treated with Emulsions Containing Peppermint Essential Oil (Menthae piperitae aetheroleum)

The objective of the work was to obtain materials with aromatherapeutic and antibacterial properties by applying emulsions based on peppermint essential oil (PEO) onto cotton fabric. For this purpose, some emulsions based on PEO incorporated in various matrices (chitosan + gelatin + beeswax; chitosan + beeswax; gelatin + beeswax and gelatin + chitosan) were prepared. Tween 80 was used as a synthetic emulsifier. The influence of the nature of matrices and of the concentration of Tween 80 on the stability of the emulsions was evaluated by the creaming indices. The materials treated with the stable emulsions were analyzed in terms of sensory activity, of the comfort characteristics, and of the gradual release of the PEO in the artificial perspiration solution. The sum of volatile components retained by samples after exposure to air was determined by GC-MS. The results regarding antibacterial activity showed that materials treated with emulsions have a good inhibitory effect on S. aureus (diameters of the inhibition zones between 53.6 and 64.0 mm) and on E. coli (diameters of the inhibition zones between 38.3 and 64.0 mm). Our data suggest that by applying peppermint-oil-based emulsions on a cotton support, aromatherapeutic patches, bandages and dressings with antibacterial properties can be obtained.

Bigel formulations based on sesame oleogel with probiotics alginate hydrogel: A novel structure for nutritious spreadable butter

As a replacement for saturated fats, bigel butter spread (BgBs) based on sesame oleogel and alginate hydrogel was developed. Morphology, oxidative stability, microbiological, chemical, and sensory analysis were assessed. The results demonstrated that unsaturated fatty acids were higher in cinnamon (73.87 %) than in plain (71.57 %) BgBs. The peroxide value was higher in plain (5.25 meqO₂/kg) than in cinnamon BgBs (4.29 meqO₂/kg). Cinnamon BgBs had 44.44 % more antioxidant activity compared to plain BgBs (40.20 %). Moreover, BgBs products kept their probiotic counts at >7 log cycles. The cinnamon BgBs had a lower microbial load than plain BgBs. The chemical composition of the BgBs products did not change significantly. But the pH values slightly dropped with the storage time. The sensory evaluation of plain and cinnamon BgBs did not significantly differ from one another. However, the period of storage and the addition of the cinnamon oil significantly affected the flavor ratings.

Flavour encapsulation: A comparative analysis of relevant techniques, physiochemical characterisation, stability, and food applications

Flavour is an important component that impacts the quality and acceptability of new functional foods. However, most flavour substances are low molecular mass volatile compounds, and direct handling and control during processing and storage are made difficult due to susceptibility to evaporation, and poor stability in the presence of air, light, moisture and heat. Encapsulation in the form of micro and nano technology has been used to address this challenge, thereby promoting easier handling during processing and storage. Improved stability is achieved by trapping the active or core flavour substances in matrices that are referred to as wall or carrier materials. The latter serve as physical barriers that protect the flavour substances, and the interactions between carrier materials and flavour substances has been the focus of many studies. Moreover, recent evidence also suggests that enhanced bioavailability of flavour substances and their targeted delivery can be achieved by nanoencapsulation compared to microencapsulation due to smaller particle or droplet sizes. The objective of this paper is to review several relevant aspects of physical-mechanical and physicochemical techniques employed to stabilize flavour substances by encapsulation. A comparative analysis of the physiochemical characterization of encapsulates (particle size, surface morphology and rheology) and the main factors that impact the stability of encapsulated flavour substances will also be presented. Food applications as well as opportunities for future research are also highlighted.

Alginate Particles for Encapsulation of Phenolic Extract from Spirulina sp. LEB-18: Physicochemical Characterization and Assessment of In Vitro Gastrointestinal Behavior

Encapsulation can be used as a strategy to protect and control the release of bioactive extracts. In this work, an extract from Spirulina sp. LEB-18, rich in phenolic compounds, was encapsulated in biopolymeric particles (i.e., composed of alginate) and characterized concerning their thermal behavior using differential scanning calorimetry (DSC), size, morphology, swelling index (S), and encapsulation efficiency (EE%); the release profile of the phenolic compounds at different pHs and the particle behavior under in vitro gastrointestinal digestion were also evaluated. It was shown that it is possible to encapsulate the phenolic extract from Spirulina sp. LEB-18 in alginate particles with high encapsulation efficiency (88.97%). It was also observed that the particles are amorphous and that the encapsulated phenolic compounds were released at a pH 7.2 but not at pH 1.5, which means that the alginate particles are able to protect the phenolic compounds from the harsh stomach conditions but lose their integrity under intestinal pH conditions. Regarding bioaccessibility, it was observed that the encapsulated phenolic compounds showed higher bioaccessibility compared to phenolic compounds in free form. This work increases the knowledge about the behavior of alginate particles encapsulating phenolic compounds during in vitro gastrointestinal digestion. It also provides essential information for designing biopolymeric particle formulations encapsulating phenolic compounds for application in pharmaceutical and food products.

Zingiber officinale essential oil-loaded chitosan-tripolyphosphate nanoparticles: Fabrication, characterization and in-vitro antioxidant and antibacterial activities

Zingiber officinale essential oil (ZEO) was encapsulated in chitosan nanoparticles at different concentrations using the emulsion-ionic gelation technique and its antioxidant and antibacterial effects were investigated. The results indicated that ZEO level had a significant effect on encapsulation efficiency (EE), loading capacity (LC), particle size and zeta potential. The value obtained for EE, LC, mean particle size and zeta potential were 49.11%-68.32%, 21.16%-27.54%, 198.13-318.26 nm and +21.31-43.57 mV, respectively. According to scanning electron micrographs, the nanoparticles had a spherical shape with some invaginations due to the drying process. The presence of essential oil within the chitosan nanoparticles was confirmed by Fourier transform infrared (FTIR) spectroscopy. In vitro release studies in simulated gastrointestinal fluid (SGF) and simulated intestinal fluid (SIF) indicated an initial burst effect followed by slow release with higher release rate in acidic medium of SGF. ZEO-loaded nanoparticles showed DPPH radical scavenging activity of 20%-61% which increased by raising the ZEO level. Moreover, results of antibacterial activity revealed that Staphylococcus aureus (with inhibition zones of 19-35.19 mm2) and Salmonella typhimurium (with inhibition zones of 9.78-17.48 mm2) were the most sensitive and resistant bacteria to ZEO, respectively. Overall, chitosan nanoparticles can be considered as suitable vehicles for ZEO and improve its stability and solubility.

Thermal, structural, antimicrobial, and physicochemical characterisation of thyme essential oil encapsulated in β- and γ-cyclodextrin

The present work aimed to encapsulate the thyme essential oil (TEO) in β-cyclodextrin (BCD) and γ-cyclodextrin (GCD) complexes in two selected cyclodextrin (CD) to TEO ratios (85/15 and 80/20 w/w) and compare the physicochemical, antioxidant, and antimicrobial properties of the encapsulated powders. The inclusion complexes between CD and TEO were prepared by blending aqueous CD and TEO in ethanol followed by freeze-drying. The powder properties were assessed by measuring particle size and microstructure using SEM, FTIR, and XRD. The median values of the particle sizes (GCD: 92.0 ± 4.69 and BCD: 46.2 ± 2.56-mm) significantly influenced the encapsulation efficiency, resulting in a higher encapsulation efficiency of the GCD (92.02 ± 10.79%) than that of the BCD (56.30 ± 12.19%). The encapsulated GCD/TEO (80/20) showed higher antioxidant activity and an antimicrobial inhibitory effect against Listeria monocytogenes and Salmonella enterica sv. typhimurium. Overall, the GCD acts as a superior wall material to the BCD in the TEO encapsulation.

Biocomposites of Silk-Elastin and Essential Oil from Mentha piperita Display Antibacterial Activity

In this study, novel antimicrobial biocomposite films comprising a genetically engineered silk-elastin protein polymer (SELP) and essential oil from Mentha piperita (MP_EO) have been fabricated and tested for the antibacterial performance. SELP/MP_EO biocomposite films were prepared by solvent casting using water as the solvent and aqueous emulsions of MP_EO at different concentrations. Emulsions of MP_EO were investigated, showing that the mixing method, relative amount of surfactant, and the presence of SELP influence particle size and homogeneity. The aqueous emulsions of SELP/MP_EO were characterized by a population of particles between 100 and 300 nm, depending on the MP_EO concentration. The emulsified oil droplets at the highest concentration showed to be homogeneously distributed into the SELP matrix and demonstrated antibacterial activity against Escherichia coli, Bacillus subtilis, and Staphylococcus aureus. Moreover, the antibacterial activity of the biocomposite films was retained after a period of storage for 7 days at 4 °C. The formulation of composites comprising natural active fillers and recombinant protein polymers opens opportunities to develop new green, functional biocomposite materials, paving the way for a new generation of multifunctional materials.

Characterization and stability of peppermint oil emulsions using polyglycerol esters of fatty acids and milk proteins as emulsifiers

Three peppermint oil emulsions using polyglycerol esters of fatty acids-casein (PGFE-CN), polyglycerol esters of fatty acids-sodium caseinate (PGFE-NaCN), and polyglycerol esters of fatty acids-whey protein isolate (PGFE-WPI) as emulsifiers were fabricated, and the droplet size, zeta potential, viscosity, and stability of emulsions were determined. The experimental results showed that the emulsion containing PGFE-CN has relatively smaller droplet size of 231.77 ± 0.49 nm. No significant changes were observed on the average particle size, polydispersity index and zeta potential during 4-week of storage, indicating that the emulsions kept stable against pH, salt ion, freeze-thaw, and storage. Fourier transform infrared spectrometer (FTIR) results showed that the electrostatic interaction occurs between CN and PGFE in the emulsion. The confocal laser scanning microscope (CLSM) was used to observe the microstructure of the emulsion, proving that droplets were evenly distributed throughout the aqueous phase by PGFE-CN emulsifier. The protein-stabilized emulsions can be used as potential carriers for the delivery of the lipophilic nutrients such as peppermint oil. PRACTICAL APPLICATION: PGFE-CN emulsifier can be directly added to the beverage systems containing oil or protein, such as coconut milk, peanut milk, and walnut milk. It can enhance the stability of beverage, prevent the precipitation, stratification, and oil floating, improve the homogeneity of the system and therefore extend the shelf life.

Electro-hydrodynamic assisted synthesis of lecithin-stabilized peppermint oil-loaded alginate microbeads for intestinal drug delivery

Peppermint oil (PO) is the most prominent oil using in pharmaceutical formulations with its significant therapeutic value. In this sense, this oil is attracting considerable attention from the scientific community due to its traditional therapeutic claim, biological and pharmacological potential in recent research. An organic solvent-free and environment-friendly electrohydrodynamic assisted (EHDA) technique was employed to prepared PO-loaded alginate microbeads. The current study deals with the development, optimization, in vitro characterization, in vivo gastrointestinal tract drug distribution and ex-vivo mucoadhesive properties, antioxidant, and anti-inflammatory effects of PO-loaded alginate microbeads. The optimization results indicated the voltage and flow rate have a significant influence on microbeads size and sphericity factor and encapsulation efficiency. All these optimized microbeads showed a better drug release profile in simulated intestinal fluid (pH 6.8) at 2 h. However, a minor release was found in acidic media (pH 1.2) at 2 h. The optimized formulation showed excellent mucoadhesive properties in ex-vivo and good swelling characterization in intestine media. The microbeads were found to be well distributed in various parts of the intestine in in vivo study. PO-loaded alginate microbeads similarly showed potential antioxidant effects with drug release. The formulation exhibited possible improvement of irritable bowel syndrome (IBS) in MO-induced rats. It significantly suppressed proinflammatory cytokines, i.e., interleukin- IL-1β, and upregulated anti-inflammatory cytokine expression, i.e., IL-10. It would be a promising approach for targeted drug release after oral administration and could be considered an anti-inflammatory therapeutic strategy for treating IBS.

From oil to microparticulate by prilling technique: Production of polynucleate alginate beads loading Serenoa Repens oil as intestinal delivery systems

Natural oils that are rich in biologically active polyunsaturated fatty acids have many health benefits but have insufficient bioavailability and may oxidize in the gastrointestinal tract. For these reasons and to improve the handling as well, the possibility of incorporating a natural oil, extracted from Serenoa Repens fruits (SR-oil), in alginate-based beads was investigated. SR-oil has been used from centuries in both traditional and modern medicine for various nutraceutical or therapeutic purposes such as, in both sexes, as a general tonic, for genitourinary problems, to increase sexual vigor, as a diuretic or to treat in male lower urinary tract symptoms and benign prostatic hyperplasia. In this study, alginate-based beads prepared by vibration technology, also known as prilling technique, were explored as SR-oil delivery systems. Twenty-seven different formulations (F1-F27) were produced starting from stable emulsions for the period of the production. The formulations having spheroid shape (sfericity factor <0.07), high formulation yield (>90%) and high encapsulation efficiency (EE% > 80) were selected for further characterizations. Gas chromatographic analysis revealed a high loading of lauric acid as principal component of SR-oil allowing to calculate the content of total fatty acids (>50%) into the beads. Swelling behavior and release features were also studied at different pH values. The swelling of the beads and their SR-oil release were negligible for the first 2 h in simulated gastric fluid (pH 1.2), and appreciable in simulated intestinal fluid (pH 6.8). The release data were fitted by various equations to define the release kinetic mechanism. In addition, the selected formulation (F16) was stable to the oxidation not only during the formulation process, but also after 3 months of storage at room temperature. In summary, these polynucleate alginate beads, produced by prilling technique, are promising systems for improving the intestinal specific delivery and bioavailability of health-promoting bioactive SR-oil.

Rapid Screening of Mentha spicata Essential Oil and L-Menthol in Mentha piperita Essential Oil by ATR-FTIR Spectroscopy Coupled with Multivariate Analyses

Mentha piperita essential oil (EO) has high economic importance because of its wide usage area and health-beneficial properties. Besides health-beneficial properties, Mentha piperita EO has great importance in the flavor and food industries because of its unique sensory and quality properties. High-valued essential oils are prone to being adulterated with economic motivations. This kind of adulteration deteriorates the quality of authentic essential oil, injures the consumers, and causes negative effects on the whole supply chain from producer to the consumer. The current research used fast, economic, robust, reliable, and effective ATR-FTIR spectroscopy coupled chemometrics of hierarchical cluster analysis(HCA), principal component analysis (PCA), partial least squares regression (PLSR) and principal component regression (PCR) for monitoring of Mentha spicata EO and L-menthol adulteration in Mentha piperita EOs. Adulterant contents (Mentha spicata and L-menthol) were successfully calculated using PLSR and PCR models. Standard error of the cross-validation SECV values changed between 0.06 and 2.14. Additionally, bias and press values showed alteration between 0.06 and1.43 and 0.03 and 41.15, respectively. Authentic Mentha piperita was successfully distinguished from adulterated samples, Mentha spicata and L-menthol, by HCA and PCA analysis. The results showed that attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, coupled with chemometrics could be effectively used for monitoring various adulterants in essential oils.

Synthesis and characterization of novel organo-hydrogel based agar, glycerol and peppermint oil as a natural drug carrier/release material

The very recent Covid-19 pandemic has made the need to understand biocompatible polymers as support material in drug delivery systems and controlled release clearer, especially for organo-hydrogels. This study aims to synthesize various new polymeric materials called gels, hydrogels, and organo-hydrogels according to the monomer used and to investigate their use as drug release systems. The agar-glycerol (AG) pair was used to synthesize the polymers, N, N, methylene bisacrylamide (MBA, m) and glutaraldehyde (GA, g) were used as cross-linkers and peppermint oil (PmO) was included to obtain the organo-hydrogels. Therefore, one AG gel and two p (AG-m) and p (GA-g) hydrogels were synthesized within the scope of the study. Six different organo-hydrogels based on p(AG-m-PmO) or p (AG-g-PmO) were also synthesized by varying the amount of peppermint oil. Paracetamol and carboplatin were selected as the sample drugs. Synthesized gels, hydrogels and organo-hydrogels were characterized by FTIR and SEM analysis. Additionally, swelling behaviors of the synthesized gels were investigated in different media (ID water, tap water, ethanol, acetone, ethanol/ID water (1:1), acetone/ID water (1:1) and gasoline) and at different pHs. Moreover, it was determined that organo-hydrogels were blood compatible and had antioxidant properties based on hemolysis, blood clotting and antioxidant analysis. Therefore, the release of paracetamol (a known antipyretic-painkiller, recommended and used in the treatment of Covid-19) and carboplatin (widely used in cancer treatment) were studied. Evidently, as the amount of PMO oil increases, the -OH groups in organo-hydrogels will increase and the chemical and physical bonding rates will increase; therefore it was observed that increasing peppermint oil in the organo-hydrogels structure to 0.3 mL stimulated the release of the drugs. For instance, maximum paracetamol release amount from p(AG-g-PmO) and p(AG-m-PmO) organo-hydrogels was calculated to be 72.3% at pH 7.4 and 69.8% at pH 2.0, respectively. The maximum carboplatin release amount from p(AG-g-PmO) and p(AG-m-PmO) organo-hydrogels was calculated to be 99.7% at pH 7.4 and 100% at pH 7.4, respectively. It was concluded that the synthesized organo-hydrogels might easily be used as drug carrier and controlled drug release materials.

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Novel organo-hydrogels were synthesized using agar, glycerol and peppermint oil for drug carrier and controlled release.

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Biocompatibility and antioxidant properties of organo-hydrogels were investigated.

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Covid-19 and cancer sensitive drugs (Paracetamol and Carboplatin) were accomplished.

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The superior properties of the synthesized organo-hydrogels make them useful in biomedical, pharmaceutical and drug delivery systems applications.

Development of New Formula Microcapsules from Nutmeg Essential Oil Using Sucrose Esters and Magnesium Aluminometasilicate

Essential oils are volatile liquids which evaporate and lose their pharmacological effect when exposed to the environment. The aim of this study is to protect nutmeg essential oil from environmental factors by encapsulation (shell material, sodium alginate) and determine the influence of crosslinker concentration (2%, 5% calcium chloride), different emulsifiers (polysorbate 80, sucrose esters), and magnesium aluminometasilicate on microcapsule physical parameters, encapsulation efficiency (EE), swelling index (SI), and other parameters. Nutmeg essential oil (NEO)-loaded calcium alginate microcapsules were prepared by extrusion. The swelling test was performed with and without enzymes in simulated gastric, intestinal, and gastrointestinal media. This study shows that the crosslinker concentration has a significant influence on EE, with 2% calcium chloride solution being more effective than 5%, and capsules being softer with 2% crosslinker solution. Using sucrose esters, EE is higher when polysorbate 80 is used. The swelling index is nearly three times higher in an intestinal medium without enzymes than in the medium with pancreatin. Microcapsule physical parameters depend on the excipients: the hardest capsules were obtained with the biggest amount of sodium alginate; the largest with magnesium aluminometasilicate. Sucrose esters and magnesium aluminometasilicate are new materials used in extrusion.

Encapsulation of Black Seed Oil in Alginate Beads as a pH-Sensitive Carrier for Intestine-Targeted Drug Delivery: In Vitro, In Vivo and Ex Vivo Study

Black seed oil (BSO) has been used for various therapeutic purposes around the world since ancient eras. It is one of the most prominent oils used in nutraceutical formulations and daily consumption for its significant therapeutic value is common phenomena. The main aim of this study was to develop alginate-BSO beads as a controlled release system designed to control drug release in the gastrointestinal tract (GIT). Electrospray technology facilitates formulation of small and uniform beads with higher diffusion and swelling rates resulting in process performance improvement. The effect of different formulation and process variables was evaluated on the internal and external bead morphology, size, shape, encapsulation efficiency, swelling rate, in vitro drug release, release mechanism, ex vivo mucoadhesive strength and gastrointestinal tract qualitative and quantitative distribution. All the formulated beads showed small sizes of 0.58 ± 0.01 mm (F8) and spherical shape of 0.03 ± 0.00 mm. The coefficient of weight variation (%) ranged from 1.37 (F8) to 3.93 (F5) ng. All formulations (F1–F9) were studied in vitro for release characteristics and swelling behaviour, then the release data were fitted to various equations to determine the exponent (ns), swelling kinetic constant (ks), swelling rate (%/h), correlation coefficient (r²) and release kinetic mechanism. The oil encapsulation efficiency was almost complete at 90.13% ± 0.93% in dried beads. The maximum bead swelling rate showed 982.23 (F8, r² = 0.996) in pH 6.8 and the drug release exceeded 90% in simulated gastrointestinal fluid (pH 6.8). Moreover, the beads were well distributed throughout various parts of the intestine. This designed formulation could possibly be advantageous in terms of increased bioavailability and targeted drug delivery to the intestine region and thus may find applications in some diseases like irritable bowel syndrome.