Microencapsulation Technology Research Articles

Microencapsulation of phase change materials (PCMs) at low temperature using a novel thin film UV reactor

Phase-change materials (PCMs) have shown great promise for energy management in buildings and gained attention in the field of sustainable and energy-efficient construction. However, to fully utilize PCMs, their proper containment is vital. In this study, a photo-induced polymerization process using a new thin film UV reactor at room temperature for PCM microencapsulation in polymer shells of different acrylate-based monomers was investigated. Four different acrylate-based monomers were investigated: namely, methyl methacrylate (MMA), ethyl acrylate (EAA), butyl acrylate (BAA), and tert-butyl acrylate (TBMA). Commercial Rubitherm’s RT21 PCM (Tpeak,melting ∼ 21 °C and ΔH = 123 kJ/kg) and Irgacure® 819 as a photosensitive initiator were used. When MMA or EAA were used, scanning electron microscopy (SEM) images revealed smooth surfaces of PCM microcapsules (m-PCMs) with a hemispherical shape. While m-PCMs with rough surfaces, buckles, and dimples were found when BAA and TBMA were applied. The results showed that the highest levels of microencapsulation efficiency, yield, and PCM content were observed for MMA and EAA samples. The TBMA sample shows low values of microencapsulation efficiency and yield (about 29.1 and 53.4 %, respectively). Furthermore, results showed that adding cross-linking agents to the recipe has had multiple favourable effects. It has mitigated sub-cooling, increased PCM content, improved microencapsulation efficiency, and boosted the overall yield of PCM. In conclusion, the current work will contribute to the development of a microencapsulation technology of PCMs that overcomes the shortcomings of long time and high temperature needed in the present traditional microencapsulation procedure.

Preparation and performance enhancement of MXene/Na2HPO4·12H2O@SiO2 phase change microcapsule

Currently, the leakage problem of phase change materials can be solved by the microencapsulation technology. Inorganic hydrated salt materials have the advantages of high latent heat density, high thermal conductivity and low cost. How to construct inorganic hydrated salt microcapsules with excellent heat storage capacity and photothermal conversion performance maintains a challenge. In this work, the MXene/Na2HPO4·12H2O@SiO2 (MXene/MPCMs) composite phase change microcapsules were designed and prepared. The Na2HPO4·12H2O was directly used as phase change material and TEOS was used as raw material to generate SiO2 wall material. The MXene played a key and important role in simultaneously enhancing their photothermal conversion efficiency while maintaining available latent heat. The prepared composite microcapsules (MPCM-1) showed more obvious heat storage and release characteristics, and the latent heat reached 169.62 J/g. Besides, when the hydrated salt was encapsulated in silica shell, the supercooling degree of hydrated salt was reduced from 14.2 °C to 10.1 °C. With the increase of MXene content, the maximum surface temperature of microcapsules significantly increased. Based on the results of surface temperature distribution, the photothermal conversion ability and heat transfer rate of microcapsules were effectively improved, which was mainly attributed to the remarkable light absorption conversion ability of MXene. When the MXene was added, the MXene/MPCMs still showed excellent heat storage properties (∼ 156.64 J/g). At the same time, the MXene/MPCMs showed good chemical compatibility, crystallization characteristics and thermal stability. Considering available performance enhancement, the prepared microcapsules show good application prospect in solar energy utilization.

Double-shell microstructures based on thermochromic materials and biomass flame retardants towards solving the fire and icing hazards

Due to the extreme dynamic weather, important industrial facilities and infrastructure providing vital support for people’s lives usually face the hazards of fire and icing, especially in the weather of thunderstorm and ice. Therefore, to further establish a safe community, we develop a dual-functional polyurea (PUA) coating used as protective materials by introducing flame retardancy and solar de-icing performance. Based on the microencapsulation and electrostatic self-assembly technologies, flame-retardant and thermochromic microcapsules (TCM) are firstly prepared and then added into PUA resin, by using melamine resin and bio-based phytic acid/chitosan (PA/CS) hybrids as double-shell materials. The high phosphorus content of PA and the carbon-forming effect of CS together play a synergistic flame retardant effect, not only improving the thermal stability of microcapsules but also enhancing the flame retardant property of PUA coating. In the cone calorimetry test, the ignition time of TCM@PA/CS@PUA-3 is longer, and the pHRR is reduced by 19.93 %, which shows the improvement of flame retardant performance. Due to the thermochromic mechanism, TCM@PA/CS@PUA composite coatings are able to adjust the photo-thermal conversion ability according to different environment temperature, achieving less temperature in hot environment and higher temperature in cold environment. The excellent photo-thermal conversion ability also promotes the ice melting and slide in 525 s. This polyurea composite coating with both flame retardant and de-icing properties shows great potential for maintaining the normal operation and safety of outdoor industrials and infrastructure in extremely dynamic weather conditions.

Microencapsulated Benzoyl Peroxide for Rosacea in Context: A Review of the Current Treatment Landscape.

Rosacea, a chronic skin condition affecting millions of people in the USA, leads to significant social and professional stigmatization. Effective management strategies are crucial to alleviate symptoms and improve patients' quality of life. Encapsulated benzoyl peroxide 5% (E-BPO 5%) is a newly FDA-approved topical treatment for rosacea that shows promise in enhancing therapeutic response and minimizing skin irritation. This review aims to assess the role of recently FDA approved E-BPO 5% in the current treatment landscape for rosacea management, as it is not yet included in clinical guidelines that predominantly rely on older approved therapies. The review focuses on randomized controlled trials conducted in English-speaking adults. It evaluates the efficacy, safety, and tolerability of various US Food and Drug Administration (FDA)-approved agents used for rosacea treatment, including E-BPO cream, metronidazole gel, azelaic acid gel and foam, ivermectin cream, minocycline foam, oral doxycycline, brimonidine gel, and oxymetazoline HCl cream. Existing therapies have been effective in reducing papulopustular lesions and erythema associated with rosacea for many years. E-BPO 5% offers a promising addition to the treatment options due to its microencapsulation technology, which prolongs drug delivery time and aims to improve therapeutic response while minimizing skin irritation. Further research is necessary to determine the exact role of E-BPO 5% in the therapeutic landscape for rosacea. However, based on available evidence, E-BPO 5% shows potential as a valuable treatment option for managing inflammatory lesions of rosacea, and it may offer benefits to patients including: rapid onset of action, demonstrated efficacy by Week 2, excellent tolerability, and sustained long-term results for up to 52 weeks of treatment.

Production Technology and Quality Assessment of Microcapsules of <i>Lycopus europaeus</i> L. Herb Dry Extract

SCIENTIFIC RELEVANCE. The high hygroscopicity and poor flowability of herbal extracts complicate the manufacturing of medicinal products based on these active substances. Microencapsulation of dry herbal extracts reduces their hygroscopicity, improves their flowability, and expands their applicability. Further development of medicinal products based on herbal extracts requires a comparative analysis of the relationships between the quality of microparticles and the selected microencapsulation method.AIM. This study aimed to conduct a practical evaluation of a previously developed microcapsule production technology and to evaluate the quality of a microencapsulated dry extract of Lycopus europaeus L. herb.MATERIALS AND METHODS. The study analysed a dry extract of Lycopus europaeus herb with a thyrostatic effect, which was microencapsulated by dispersion. A film-forming agent was used to form the microcapsule shells (gelatine, grade P-11). The microcapsules were characterised by the following pharmacopoeial quality parameters: particle size, moisture content, and flowability. The qualitative and quantitative analysis of the dry extract of Lycopus europaeus herb used thin-layer chromatography and spectrophotometry.RESULTS. The study identified the optimum ratios for Lycopus europaeus herb dry extract and excipients as well as the procedure for ingredient addition during the microencapsulation process. The resulting microcapsules were homogeneous particles with a diameter of 50–300 µm, a moisture content of 3.21±0.12%, and a good flow. The encapsulation efficiency of the dispersion method reached 95.0±1.3%. In contrast to non-encapsulated dry extract particles, the particles of microencapsulated Lycopus europaeus herb dry extract had a spherical shape, smooth surface, and improved technological properties.CONCLUSIONS. The authors developed a microencapsulation technology for Lycopus europaeus herb dry extract. The study results confirmed the efficiency of the microencapsulation method in reducing the hygroscopicity of Lycopus europaeus herb dry extract, increasing its stability during storage, and optimising the further development of dosage forms.

Development of chitosan/carrageenan macrobeads for encapsulation of Paenibacillus polymyxa and its biocontrol efficiency against clubroot disease in Brassica crops

Clubroot, caused by the obligate parasite Plasmodiophora brassicae, is one of the most important diseases of brassicas. The antagonistic bacterium Paenibacillus polymyxa ZF129 can suppress clubroot while its effectiveness is often unstable. To control clubroot more effectively, the macrobeads for controlled release of ZF129 were prepared using microencapsulation technology. Macrobeads with various ratios of chitosan (2 % w/w): carrageenan (0.3 % w/v) were prepared by an ionotropic gelation method and the bacteria ZF129 was loaded into macrobeads. The 1:1 chitosan: carrageenan showed the maximum swelling ratio (634 %), and the maximum survival rate (61.52 ± 1.12 %) after freeze-drying. Fourier transform infrared revealed the electrostatic interactions between chitosan and carrageenan. The macrobeads can efficiently release ZF129 strains into phosphate buffer solution and reach equilibrium in 48 h. The maximum number of bacteria cells to be released in the soil was observed after 25–30 days. The control efficacy of ZF129 macrobeads (chitosan: carrageenan, 1:1) and ZF129 culture against clubroot disease was 76.33 ± 3.65 % and 59.76 ± 4.43 % in greenhouse experiments, respectively and the control efficacy was calculated as 60.74 ± 5.00 % for ZF129 macrobeads and 40.94 ± 4.05 % for ZF129 culture under field experiments, respectively. The ZF129 macrobeads had significant growth-promoting effects on pak choi and Chinese cabbage. The encapsulation method described in this study is a prudent approach toward efficient biopesticides utilization with reduced environmental implications.

CHARACTERISTICS AND APPLICATION OF BIOPOLYMERS FOR MICROENCAPSULATION OF BIOLOGICALLY ACTIVE SUBSTANCES

In the feeding of highly productive agricultural animals and poultry, an important role belongs to the quality and safety of compound feed products, for the production of which premixes or preparations of biologically active substances are used. Increasingly, probiotic supplements based on live microorganisms are used in the feeding of farm animals and poultry, which, among other things, provide stable immunity to infectious diseases without using antibiotics in the diet. As a result, the general condition improves and the productivity of animals and the quality of livestock products increase. Today, one of the urgent issues is the stabilization of probiotic microorganisms. Thus, the microencapsulation technology allows you to cover the particles of the probiotic supplement with an individual shell to obtain a product with a directed effect and an adjustable time of release of the constituent substance. The article deals with protein metabolism during feeding of highly productive breeds of cattle. Methods of cell stabilization and advantages of stabilized forms of probiotics are presented. Technologies and types of shell materials widely used for microencapsulation of probiotics are analyzed. The use of a specific microencapsulation technology or material depends on the properties of the specific probiotic strain. Organic and inorganic substances, synthetic materials and natural biodegradable polymers are used to stabilize the cells of microorganisms. The most popular biopolymers used for microencapsulation are considered in detail - alginates, carrageenans, chitosan, starch, gum arabic, pectin, gelatin, whey protein. The structural composition, production methods, functional characteristics, volumes of global production of the considered biopolymers are given. The use of microencapsulation of probiotic microorganisms with natural biopolymers for the purpose of stabilizing probiotics in animal feed is an innovative approach.

A novel infant microbiome formula (SIM03) improved eczema severity and quality of life in preschool children

Altered gut microbiome composition has been reported in children with eczema and interventions that restore beneficial bacteria in the gut may improve eczema. This open-label pilot study aimed to investigate the efficacy of a novel infant microbiome formula (SIM03) in young children with eczema. Pre-school Chinese children aged 1–5 years old with eczema received SIM03 twice daily for three months. The novelty of SIM03 consists of both the use of a patented microencapsulation technology to protect the viability of unique Bifidobacterium bifidum and Bifidobacterium breve strains identified through big data analysis of large metagenomic datasets of young Chinese children. Paired stool samples at baseline and following SIM03 were analyzed by metagenomics sequencing. Generalized estimating equation was used to analyze changes in eczema severity, skin biophysical parameters, quality of life and stool microbiome. Twenty children aged 3.0 ± 1.6 years (10 with severe eczema) were recruited. Treatment compliance was ≥ 98%. SCORing Atopic Dermatitis score decreased significantly at two months (P = 0.008) and three months (P < 0.001), while quality of life improved significantly at 1, 2, and 3 months. The relative abundance of B. breve and microbial pathways on acetate and acetyl-CoA synthesis were enriched in stool samples at one month (P = 0.0014). Children who demonstrated increased B. bifidum after SIM03 showed improvement in sleep loss (P = 0.045). Relative abundance of B. breve correlated inversely with eczema extent (P = 0.023) and intensity (P = 0.019) only among patients with increased B. breve at Month 3. No serious adverse event was observed. In conclusion, SIM03 is well tolerated. This patented microbiome formula improves disease severity and quality of life in young eczematous children by enhancing the delivery of B. bifidum and B. breve in the gut. SIM03 is a potential treatment option for childhood eczema.

Microencapsulation for Pharmaceutical Applications: A Review.

In order to improve bioavailability, stability, control release, and target delivery of active pharmaceutical ingredients (APIs), as well as to mask their bitter taste, to increase their efficacy, and to minimize their side effects, a variety of microencapsulation (including nanoencapsulation, particle size <100 nm) technologies have been widely used in the pharmaceutical industry. Commonly used microencapsulation technologies are emulsion, coacervation, extrusion, spray drying, freeze-drying, molecular inclusion, microbubbles and microsponge, fluidized bed coating, supercritical fluid encapsulation, electro spinning/spray, and polymerization. In this review, APIs are categorized by their molecular complexity: small APIs (compounds with low molecular weight, like Aspirin, Ibuprofen, and Cannabidiol), medium APIs (compounds with medium molecular weight like insulin, peptides, and nucleic acids), and living microorganisms (such as probiotics, bacteria, and bacteriophages). This article provides an overview of these microencapsulation technologies including their processes, matrix, and their recent applications in microencapsulation of APIs. Furthermore, the advantages and disadvantages of these common microencapsulation technologies in terms of improving the efficacy of APIs for pharmaceutical treatments are comprehensively analyzed. The objective is to summarize the most recent progresses on microencapsulation of APIs for enhancing their bioavailability, control release, target delivery, masking their bitter taste and stability, and thus increasing their efficacy and minimizing their side effects. At the end, future perspectives on microencapsulation for pharmaceutical applications are highlighted.

Microencapsulation in food processing - A review study

Microencapsulation is one of the efficient, advanced and promising technologies in the field of food processing. The technology involves the protection of different valuable food constituents present in a food product by the use of a suitable covering material on it. Besides, protecting the covering material allows the release of the core material in a controlled way increases shelf life and enhances the sensory qualities. The process of microencapsulation can be done by various methods such as coacervation, polymer-polymer incompatability, solvent evaporation, spray drying, fluidized bed technology, pan coating, spinning disc, extrusion, interfacial polymerization etc. This technology is being used in various fields including pharmaceutical, vectorisation, artificial organs, single dose treatment, agriculture (fungicide, herbicide, insect repellent, artificial insemination), food, printing, cosmetic, textile and defense. No single microencapsulation process is adaptable to all core materials. It is a complicated process and requires skilled person to handle the whole process. As worldwide demands for functional coatings continue to increase, new, cost effective microencapsulation technologies will be developed and the technology will remain at the forefront of future.

Application of microencapsulated fibrous carrier inhibitors in suppressing flake aluminum dust explosion: Performance and mechanism

Flake aluminum powder (FAl), due to its larger specific surface area and higher reactivity, posing a potential threat to the process safety of involved enterprises. To mitigate the explosion caused during the production of FAl, a green composite inhibitor, Sep@CS@PA-Na, was successfully prepared in the aqueous phase using microencapsulation technology with sepiolite (Sep), chitosan (CS), and sodium phytate (PA-Na) as raw materials. The suppression of FAl explosions in a vertical combustion duct system by inhibitors with different inerting ratios (α) was investigated. The results showed that after adding Sep@CS@PA-Na with an α of 0.75, the maximum flame propagation velocity (Vmax), the average flame velocity (Vavg), and the velocity of the flame reaching the pipeline top (Vtop) decreased by 79.6%, 75.1%, and 86.2%, respectively, and the reduction of the maximum flame front pressure (Pmax) and the maximum flame pressure rise rate ((dP/dt)max) were 90.4% and 89.8%, respectively, and the peak temperature (Tp) dropped to 505°C. Combined with TG-DSC and explosion product analysis, Sep@CS@PA-Na possessed both gas-phase reaction and surface reaction suppression functions, which were mainly reflected in the dilution effect, quenching effect, and barrier effect. This work will provide technical support for the emergency prevention and control of energetic metal dust explosions.

Preparation and assessment of alginate-microencapsulated Trichoderma harzianum for controlling Sclerotinia sclerotiorum and Rhizoctonia solani on tomato

This study aimed to develop microencapsulation technology using alginate to improve the viability and performance of Trichoderma harzianum. The method of ionic gelation was used to prepare the microparticles, and the efficiency of encapsulation was estimated to be 99%. The average size of the prepared microspheres was 2600 μm (wet) and 1000 μm (dry). Scanning electron microscopy revealed that the microspheres were approximately spherical. Fourier transform infrared spectrophotometer analysis indicated an interaction between T. harzianum and the microspheres. The results of temperature resistance and light stability against ultraviolet radiation emphasized the positive impact of microencapsulation in improving the viability and resistance of T. harzianum compared to the non-microencapsulated state. The disease percentage of Rhizoctonia solani and Sclerotinia sclerotiorum in plants treated with microencapsulated T. harzianum microcapsules was 8.88 % and 20 % respectively, but in the control group was 73.33 % (p ≤ 0.05).

Stimulus triggered release of actives from composite microcapsules based on sporopollenin from Lycopodium clavatum.

Smart drug delivery systems (SDDSs) are a paradigm shift in drug delivery, particularly in microencapsulation technology where the drug is released in response to an internal and/or external stimulus. In this study, a smart microencapsulation platform was developed using three different types of stimuli triggered release of a model active (rhodamine 6G) from sporopollenin from Lycopodium clavatum. Triggers were based on pH-, thermal- and near infrared light-sensitive polymer composition. Carbopol nanogel and methylcellulose were used as responsive aqueous polymers for pH and thermally triggered release, respectively. Methylcellulose loaded with active and gold nanoparticles was used for photothermal triggered release. The formulations were encapsulated into the empty cores of sporopollenin microcapsules using the compressed tablet technique. The pH triggered release of the active was achieved above pH 7, which was mediated by the swelling of the carbopol nanogel that forced its way out of the elastic trilite scars of the sporopollenin. Results from measuring the active fluorescent intensity and its content over time confirmed the crucial role of carbopol in the pH triggered release. For the thermo-sensitive polymer methylcellulose, it was found that the release of the active from methylcellulose loaded sporopollenin was triggered upon heating the system reaching 90% whereas it levelled out at 40% for methylcellulose-free sporopollenin. The maximum amount of active was released at around 55 °C, where the sol-gel transition of the methylcellulose starts. Photothermally triggered release using near infrared (NIR) laser revealed that the amount of active released from sporopollenin loaded with both gold nanoparticles and methylcellulose was approximately four times higher than that from sporopollenin loaded with methylcellulose/active only, confirming the key role of gold nanoparticles in the release via photothermal heating of the polymer formulation.

Production of spread cheese by incorporating micro-encapsulated pepper oil with corn oil

The incorporation of functional ingredients in cheese is a new technology application in the food industry. Black pepper oil and corn oil were purchased from commercial stores and micro-encapsulated with the 0:0 g, 15:0 g, 0:15 g, 7.5:7.5 g named as T1 to T4 respectively and added into the cheese while maintaining the standard process. Prepared samples were put into 175 ml glass bottles and kept for sensory, chemical, and microbiological analyses at room temperature and then chilled. The sensory attributes were examined using the hedonic test. The exception of taste, no significant differences in qualitative attributes was identified in all samples. To assess the shelf life of the product designed for marketability, measurements were made on a regular basis for microbiological characteristics such as total plate count, yeast and molds, and coliforms, as well as chemical data such as pH, moisture content, and titratable acidity. The micro-encapsulated products showed a minimum change in the sensory and chemical attributes therefore, it can be concluded that the microencapsulation technology is useful to produce a better spread cheese.

A Systematic Review on Microencapsulation Technique and its Application

Abstract: Micro-encapsulation is the process of encapsulating a compound in a small sphere called a microsphere / microcapsule. The diameter of the microspheres can range from 1 mm up to several hundred micrometers. Many different active materials have been successfully encapsulated in microballoons / microcapsules made from polymeric and non-polymer materials such as poly (ethylene glycol), methacrylate, poly (styrene), cellulose, poly (lactide), gelatine and acacia. The content of the microcapsules is released at the appropriate time using different release mechanisms according to the end use of the encapsulated product. This technology has been used in many industries such as pharmaceuticals, agri-food, printing, cosmetics, textiles and defence. In the defence sector, it has been used to create self-healing composite as well as chemical decontamination fabrics. This review highlights the main reasons for microencapsulation technology, important techniques for the encapsulation of products and applications of the technology in various fields of science and technology.

A novel effective halogen-free biomass-based chitosan derived flame retardant through microencapsulation technology for improved flame retardancy, thermal stability of polyurethane

In this study, chitosan (CS) from fish waste was used to prepare bio-based environmentally friendly flame retardants. The hydroxyl group (-OH) of CS and the ammonium group (NH4+) of ammonium polyphosphate (APP) formed CS-APP, which was to serve as the core material. Melamine–formaldehyde (MF) resin was synthesized as the shell material through microencapsulation technology with CS-APP to prepare the novel core-shell structured flame retardant, which was subsequently introduced into polyurethane (PU) to prepare the composites. This study employed thermogravimetric analysis (TGA), the limiting oxygen index (LOI), UL-94, cone calorimetry tests (CCT), thermogravimetric analysis-FTIR (TGA-FTIR), SEM, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, smoke concentration test and tensile test to characterize the structure, thermal properties, flame retardancy, char analysis and mechanical properties of the composites. The TGA results revealed that after the addition of flame retardant, the char yield increased from 0.5 wt% (pristine PU) to 12.0 wt% (the composite), and the thermal stability of the pristine PU was improved. Furthermore, the LOI increased from 18.2 % to 28.4 %, and the UL-94 level increased from fail to V-0 for the composites. These results revealed that adding MF(CS-APP) to pristine PU resulted in high flame-retarding performance of the composites.

Preparation of isocyanate microcapsules by complex coacervation and its application in plywood

ABSTRACT At present, the use of isocyanate adhesives mostly requires the assistance of solvents, which can cause adverse environmental pollution and health effects. The aqueous isocyanate avoids the shortcomings of the solvent, but shortens the working life of the isocyanate. Isocyanate microcapsules can avoid these shortcomings, and can also solidify isocyanate to improve the efficiency of isocyanate use. In this study, microencapsulation technology was used to protect the highly reactive -NCO group, improve the stability of isocyanate, and prolong the working life of isocyanate in water-based wood adhesives. That is, isocyanate microcapsules with gum Arabic/gelatin as shell and isocyanate as core were prepared in oil-in-water emulsion by complex coacervation. In addition, the preparation process was optimized by changing the parameters. Then, the prepared isocyanate microcapsules were characterized and analyzed by Fourier transform infrared spectrometer, Scanning electron microscope, Particle size analyzer, etc. Finally, plywood was prepared by using the prepared isocyanate microcapsules in the wood adhesive. The results showed that, the particle size of isocyanate microcapsules was controllable, and the content of active groups and core in the prepared isocyanate microcapsules can reach a high level. The isocyanate microcapsules extend the working life of isocyanates from about 30 mins to 5 hours, and significantly improve the stability of isocyanates. The bonding strength of the prepared plywood meets the requirements of (Class I plywood) with only 20% -NCO addition.

Design and evaluation of microencapsulation technology to reduce the environmental impact of copper fungicides in vineyards

Grapevine is a relevant crop in the European area, that has been traditionally linked to the use of copper fungicides for downy mildew control (Plasmopara viticola). The continued use among the years of this type of copper fungicides has caused an environmental impact, mainly accumulating copper ions in the soil and also resulting in surface and groundwater pollution. To reduce the amount of copper used in vineyard crop protection strategies, and for instance, the contamination, a microencapsulated copper product has been developed. Deposition trials in artificial vegetation were assessed in order to define the optimal formulation characteristics linked with leaf deposit. Also, field trials in real conditions were performed to compare the newly developed copper product with a conventional one. These studies were completed with an evaluation of the microencapsulated product behaviour into two different soil types and its leaching that can consequently be potential groundwater contamination. Microencapsulated formulation resulted in higher deposition compared to the reference product. The obtained results are a relevant drawing up on a way to reduce the amount of copper used, due to the microencapsulated product having the potential to reduce the amount of copper used in vineyard crop protection and the environmental impact they cause.

An approach to mass produce peppermint oil-sodium alginate composite microcapsules by drop-on-demand system loaded with stabilized nanoemulsion

ABSTRACT Microencapsulation technology has found widespread applications in current fields of food industries. In this study, by combining water-in-oil emulsion with drop-on-demand (DOD) technique, we successfully produced sodium alginate (SA) shell microcapsules containing peppermint oil (PO). Response surface methodology (RSM) was employed to optimize the surfactant used for nanoemulsification. A comprehensive investigation into the morphology, structure, and encapsulation efficiency of resulting microcapsules was conducted. The study revealed that various parameters, especially of Hydrophilic-Lipophilic Balance (HLB) values, can affect the physical properties of PO/SA nanoemulsion. The optimized formulation achieved emulsions with a mean droplet size of 46.60 nm. Microcapsules with different shell/core ratios (2, 1, and 0.5) were prepared by pulse duration of 20 ms, exhibiting varying antibacterial activities against Escherichia coli in subsequent tests. This work confirms the feasibility of nanoemulsion-DOD system, highlighting the potential of PO/SA microcapsules as a more environmentally friendly alternative to conventional antimicrobials.

Lutein-Rich Beverage Alleviates Visual Fatigue in the Hyperglycemia Model of Sprague-Dawley Rats.

Asthenopia is a syndrome based on the symptoms of eye discomfort that has become a chronic disease that interferes with and harms people's physical and mental health. Lutein is an internationally recognized "eye nutrient", and studies have shown that it can protect the retina and relieve visual fatigue. In this study, lutein was extracted from marigold (Tagetes erecta L.) and saponified. The purified lutein concentration measured by HPLC was 50.12 mg/100 g. Then, purified lutein was modified to be water-soluble by nanoscale modification and microencapsulation technology. Water-soluble lutein was then mixed with a leaching solution of Chinese wolfberry and chrysanthemum to make a functional beverage. The effects of this beverage on hepatic antioxidant enzymes and the alleviation of visual fatigue in a rat model of diabetes were investigated for 4 weeks. Lutein intake of 0.72 (medium-lutein beverage group) and 1.44 mg/mL (high-lutein beverage group) relieved visual fatigue, ameliorated turbidity symptoms of impaired crystalline lenses, reduced hepatic MDA concentration, increased hepatic GSH concentration, and significantly increased the activities of the hepatic antioxidant enzymes SOD, CAT, GSH-Px, and GR in rats. These data suggest that a lutein-rich beverage is an effective and harmless way to increase the total anti-oxidation capacity of lenses and alleviate visual fatigue.