Microencapsulation of Elsholtzia ciliata Herb Ethanolic Extract by Spray-Drying: Impact of Resistant-Maltodextrin Complemented with Sodium Caseinate, Skim Milk, and Beta-Cyclodextrin on the Quality of Spray-Dried Powders

Sweet tea extract encapsulated by different wall material combinations with improved physicochemical properties and bioactivity stability

Aim: To prepare sweet tea extract microcapsules (STEMs) via a spray-drying by applying different wall material formulations with maltodextrin (MD), inulin (IN), and gum arabic (GA). Methods: The microcapsules were characterised by yield, encapsulation efficiency (EE), particle size, sensory evaluation, morphology, attenuated total reflectance-Fourier transform infra-red spectroscopy and in vitro digestion studies. Results: The encapsulation improved the physicochemical properties and bioactivity stability of sweet tea extract (STE). MD5IN5 had the highest yield (56.33 ± 0.06% w/w) and the best EE (e.g. 88.84 ± 0.36% w/w of total flavonoids). MD9GA1 obtained the smallest particle size (642.13 ± 4.12 nm). MD9GA1 exhibited the highest retention of bioactive components, inhibition of α-glucosidase (96.85 ± 0.55%), α-amylase (57.58 ± 0.99%), angiotensin-converting enzyme (56.88 ± 2.20%), and the best antioxidant activity during in vitro gastrointestinal digestion. Conclusion: The encapsulation of STE can be an appropriate way for the valorisation of STE with improved properties.

Optimizing Encapsulation: Comparative Analysis of Spray-Drying and Freeze-Drying for Sustainable Recovery of Bioactive Compounds from Citrus x paradisi L. Peels

Spray-drying and freeze-drying are indispensable techniques for microencapsulating biologically active compounds, crucial for enhancing their bioavailability and stability while protecting them from environmental degradation. This study evaluates the effectiveness of these methods in encapsulating Citrus x paradisi L. (grapefruit) peel extract, focusing on sustainable recovery from waste peels. Key objectives included identifying optimal wall materials and assessing each encapsulation technique's impact on microencapsulation. The investigation highlighted that the choice of wall material composition significantly affects the microencapsulation's efficiency and morphological characteristics. A wall material mixture of 17 g maltodextrin, 0.5 g carboxymethylcellulose, and 2.5 g β-cyclodextrin was optimal for spray drying. This combination resulted in a sample with a wettability time of 1170 (s), a high encapsulation efficiency of 91.41%, a solubility of 60.21%, and a low moisture content of 5.1 ± 0.255%. These properties indicate that spray-drying, particularly with this specific wall material composition, offers a durable structure and can be conducive to prolonged release. Conversely, varying the precise compositions used in the freeze-drying process yielded different results: quick wettability at 132.6 (s), a solubility profile of 61.58%, a moisture content of 5.07%, and a high encapsulation efficiency of 78.38%. The use of the lyophilization technique with this latter wall material formula resulted in a more porous structure, which may facilitate a more immediate release of encapsulated compounds and lower encapsulation efficiency.

Spray-Drying Microencapsulation of Bauhinia ungulata L. var. obtusifolia Aqueous Extract Containing Phenolic Compounds: A Comparative Study Using Different Wall Materials

Species belonging to the Bauhinia genus, usually known as "pata-de-vaca", are popularly used to treat diabetes. Bauhinia ungulata var. obtusifolia (Ducke) Vaz is among them, of which the leaves are used as a tea for medicinal purposes in the Amazon region. A microencapsulation study of lyophilized aqueous extract from Bauhinia ungulata leaves, which contain phenolic compounds, using five different wall materials (maltodextrin DE 4-7, maltodextrin DE 11-14; β-cyclodextrin; pectin and sodium carboxymethylcellulose) is described in this paper. The microstructure, particle size distribution, thermal behavior, yield, and encapsulation efficiency were investigated and compared using different techniques. Using high-performance liquid chromatography, phenolics, and flavonoids were detected and quantified in the microparticles. The microparticles obtained with a yield and phenolics encapsulation efficiency ranging within 60-83% and 35-57%, respectively, showed a particle size distribution between 1.15 and 5.54 µm, spherical morphology, and a wrinkled surface. Among them, those prepared with sodium carboxymethylcellulose or pectin proved to be the most thermally stable. They had the highest flavonoid content (23.07 and 21.73 mg RUTE/g Extract) and total antioxidant activity by both the DPPH (376.55 and 367.86 µM TEq/g Extract) and ABTS (1085.72 and 1062.32 µM TEq/g Extract) assays. The chromatographic analyses allowed for quantification of the following substances retained by the microparticles, chlorogenic acid (1.74-1.98 mg/g Extract), p-coumaric acid (0.06-0.08 mg/g Extract), rutin (11.2-12.9 mg/g Extract), and isoquercitrin (0.49-0.53 mg/g Extract), compounds which considered to responsible for the antidiabetic property attributed to the species.

Microencapsulation by spray-drying and freeze-drying of extract of phenolic compounds obtained from ciriguela peel

Microcapsules of ciriguela peel extracts obtained by ultrasound-assisted extraction were prepared by spray drying, whose results were compared with those of freeze-drying as a control. The effects of spray-drying air temperature, feed flow rate and ratio of encapsulating agents (maltodextrin and arabic gum) were studied. Encapsulation efficiency, moisture content, total phenolic compounds (TPC), water activity, hygroscopicity, solubility, colorimetric parameters, phenolic profile by HPLC/DAD, simulated gastrointestinal digestion and morphology of spray-dried and freeze-dried microcapsules were evaluated, as well as their stability of TPC during 90 days storage at 7 and 25 °C. Spray-dried extract showed higher encapsulation efficiency (98.83%) and TPC (476.82 mg GAE g-1) than freeze-dried extract. The most abundant compounds in the liquid extract of ciriguela peel flour were rutin, epicatechin gallate, chlorogenic acid and quercetin. Rutin and myricetin were the major flavonoids in the spray-dried extract, while quercetin and kaempferol were in the freeze-dried one. The simulated gastrointestinal digestion test of microencapsulated extracts revealed the highest TPC contents after the gastric phase and the lowest one after the intestinal one. Rutin was the most abundant compound after the digestion of both spray-dried (68.74 µg g-1) and freeze-dried (93.98 µg g-1) extracts. Spray-dried microcapsules were of spherical shape, freeze-dried products of irregular structures. Spray-dried microcapsules had higher phenolic compounds contents after 90 days of storage at 7 °C compared to those stored at 25 °C, while the lyophilized ones showed no significant difference between the two storage temperatures. The ciriguela agro-industrial residue can be considered an interesting alternative source of phenolic compounds that could be used, in the form of bioactive compounds-rich powders, as an ingredient in pharmaceutical, cosmetic and food industries.

Encapsulation of Menthol and Luteolin Using Hydrocolloids as Wall Material to Formulate Instant Aromatic Beverages

Aromatic plants represent about 0.7% of all medicinal plants. The most common are peppermint (main active ingredient: menthol) and chamomile (main active ingredient: luteolin), which are usually consumed in "tea bags" to make infusions or herbal teas. In this study, menthol and luteolin encapsulates using different hydrocolloids were obtained to replace the conventional preparation of these beverages. Encapsulation was carried out by feeding an infusion of peppermint and chamomile (83% aqueous phase = 75% water - 8% herbs in equal parts, and 17% dissolved solids = wall material in 2:1 ratio) into a spray dryer (180 °C-4 mL/min). A factorial experimental design was used to evaluate the effect of wall material on morphology (circularity and Feret's diameter) and texture properties of the powders using image analysis. Four formulations using different hydrocolloids were evaluated: (F1) maltodextrin-sodium caseinate (10 wt%), (F2) maltodextrin-soy protein (10 wt%), (F3) maltodextrin-sodium caseinate (15 wt%), and (F4) maltodextrin-soy protein (15 wt%). The moisture, solubility, bulk density, and bioavailability of menthol in the capsules were determined. The results showed that F1 and F2 presented the best combination of powder properties: higher circularity (0.927 ± 0.012, 0.926 ± 0.011), lower moisture (2.69 ± 0.53, 2.71 ± 0.21), adequate solubility (97.73 ± 0.76, 98.01 ± 0.50), and best texture properties. Those suggest the potential of these powders not only as an easy-to-consume and ecofriendly instant aromatic beverage but also as a functional one.

Microencapsulates of Blue Maize Polyphenolics as a Promising Ingredient in the Food and Pharmaceutical Industry: Characterization, Antioxidant Properties, and In Vitro-Simulated Digestion

An anthocyanin-rich blue maize waste product was used for anthocyanin extraction. To preserve bioactive phenolic compounds, a spray-drying technique was employed using conventional wall material maltodextrin (MD), with novel one, hydroxypropyl-β-cyclodextrin (HPBCD). The obtained spray-dried maize extract (SME) and microencapsulates were analyzed based on physicochemical powder properties, chemical analysis, antioxidant activity, and digestibility. The examined microencapsulates demonstrated good powder properties, exhibited a high powder yield (up to 83%), and had a low moisture content (less than 5%). HPBCD and MD + HPBCD combinations demonstrated superior powder properties in the terms of decreasing the time necessary for rehydration (133.25 and 153.8 s, respectively). The mean average particle diameter ranged from 4.72 to 21.33 µm. DSC analyses signified high powder thermal stability, around 200 °C, related to the increasing preservation with biopolymer addition. The total phenolic and anthocyanin compounds ranged from 30,622 to 32,211 mg CE/kg (CE-catechin equivalents) and from 9642 to 12,182 mg CGE/kg (CGE-cyanidin 3-glucoside equivalents), respectively, associated with good bioactive compound protection. Microencapsulates with both carriers (15% MD and 15% HPBCD) had the highest digestibility (73.63%). Our results indicated that the microencapsulates created with the active ingredient and the wall materials (MD and HPBCD) could protect phenolic compounds/anthocyanins against ABTS radicals (63.53 and 62.47 mmol Trolox Eq/kg, respectively).

Oxidative stability and sensory evaluation of sodium caseinate-based yak butter powder

Yak butter's high unsaturated fatty acid level predisposes it to oxidation, hence must be converted into more stable forms like powder. This study aimed to spray dry yak butter using 10% yak butter and four sodium caseinate (NaCas) formulations: sample A: 100% NaCas; sample B: 50% NaCas, 50% lactose; sample C: 75% NaCas, 25% lactose; and sample D: 25% NaCas, 75% maltodextrin. The powders were vacuum and hermetically sealed, and evaluated for oxidative stability, physical and sensory properties during storage at 65 ℃ for 30 days. The results showed that samples B and D had similar and most favorable physical properties (such as, moisture, water activity, particle size, bulk density re-dispersion time, and encapsulation efficiency); though sample B, together with sample C, browned the most during storage. The majority of the sensory panelists preferred samples B and D; observed high caking in samples C and B; and the least whiteness loss and caking in samples D and A but high off-flavors in samples A and C. After storage, peroxide and thiobarbituric acid values of powder samples ranged from 34.98 to 69.54 meqO2/kg and 1.85-9.43 mg MD/kg, respectively, in the decreasing order of A, C, B, and D. Sample D, followed by B, showed the highest radical scavenging activity. Therefore, for optimum yak butter powder physical properties and oxidative stability, 50%:50%, NaCas: lactose, and 25%:75%, NaCas: maltodextrin formulations should be used. This study provides essential knowledge for butter powder processors.

Effect of Spray Drying Encapsulation on Nettle Leaf Extract Powder Properties, Polyphenols and Their Bioavailability

Nettle (Urtica dioica L.) is a plant rich in a health-promoting compounds such as polyphenols, which are sensitive and unstable compounds with low bioavailability, that need to be stabilized and protected from external influences. Therefore, the aim of this study was to examine how the temperature, type of carrier and sample to carrier ratio influence the physicochemical properties and encapsulation and loading capacity of the nettle leaf extract powder and examine the effect of encapsulation on the antioxidant capacity and bioavailability of polyphenols. The process yield ranged from 64.63–87.23%, moisture content from 1.4–7.29%, solubility from 94.76–98.53% and hygroscopicity from 13.35–32.92 g 100 g⁻¹. The highest encapsulation (98.67%) and loading (20.28%) capacities were achieved at 160 °C, β-CD:GA (3:1) and sample:carrier ratio of 1:3. Extracts encapsulated at selected conditions showed high antioxidant capacity and distinct polyphenolic profile comprised of 40 different compounds among which cinnamic acids were the most abundant. Moreover, the encapsulation increased the bioavailability of nettle leaf polyphenols, with the highest amount released in the intestinal phase. Thus, the obtained encapsulated extract represents a valuable source of polyphenols and may therefore be an excellent material for application in value-added and health-promoting products.

Microencapsulation by Spray Drying and Antioxidant Activity of Phenolic Compounds from Tucuma Coproduct (Astrocaryum vulgare Mart.) Almonds

The industrial processing of fruits in the Amazon region, such as tucuma, generates a large amount of coproducts with great nutritional potential. In this work, phenolic compounds from tucuma coproduct almonds were extracted and microencapsulated by spray drying using maltodextrin as the encapsulating agent and verified its antioxidant activity. Phenolic compounds were determined by UV spectroscopy and identified by Ultraefficiency Liquid Chromatography. Antioxidant activity was measured by ABTS and DPPH assay. Thermogravimetric techniques, infrared spectroscopy, scanning electron microscopy, moisture content and water activity were applied to characterize the microparticle. The crude extract and microparticle had total polyphenols of 135.1 mg/g ± 0.078 and 130.5 mg/g ± 0.024, respectively. Caffeic and gallic acids were identified. The crude extract and the microparticle showed good antioxidant activity by ABTS and DPPH assay, justified by the presence of the phenolic compounds found. The microparticle showed spherical and heterogeneous structures and good encapsulation efficiency from the spray drying process using maltodextrin. The results show that the extract of the tucuma almond coproduct can be used as a phenolic compound-rich source and microencapsulated with possible application for functional food production.

Ultrasound-assisted extraction of functional compound from mulberry (Morus alba L.) leaf using response surface methodology and effect of microencapsulation by spray drying on quality of optimized extract

This study aimed to optimize the ultrasound-assisted extraction (UAE) condition of mulberry leaf extract (MLE) using response surface methodology and to microencapsulate MLE by spray drying using different coating materials and ratios of coating material and MLE. The extraction results showed that MLE from condition of 60 °C (X₁, temperature), 30 min (X₂, time) and 60% v/v (X₃, ethanol concentration) exhibited the highest bioactive compound and antioxidant activity (DPPH and FRAP assay). Based on this optimal condition, MLE was further encapsulated by spray drying. It was found that MLE encapsulated with resistant maltodextrin at ratio of MLE and resistant maltodextrin 1:1 (w/w) showed the highest encapsulation yield (%) and encapsulation efficiency (%). Water solubility, moisture content and water activity were non-significant (p > 0.05) among the microcapsules. The scanning electron microscope (SEM) revealed that the types of coating material affected their microstructures and microcapsules prepared by resistant maltodextrin as coating material had a spherical shape, smooth surface and less shrinkage than microcapsules prepared by maltodextrin and gum arabic which had rough surfaces. The highest antioxidant activity was obtained from microcapsule prepared by gum arabic at ratio of MLE and gam arabic 1:2 (w/w). In conclusion, optimal condition from UAE and encapsulation by spray drying suggest the critical potential for production of functional food with improved bioactive compound stability and maximized antioxidant activity.

Evaluation of Microwave-Assisted Extraction Method for Preparation and Assessment of Thai Herbal Medicine Oral Tablets With Enriched Phytochemical Compounds

In developing countries, populations have employed herbal medicines for primary health care because they are believed to be more appropriate to the human body and have less side effects than chemically synthesized drugs. The present study aimed to develop and evaluate herbal tablets incorporated with a Thai traditional medicinal extract, U-pa-ri-waat (URW), using microwave-assisted extraction (MAE). The extraction efficiency for URW using MAE and traditional solvent extraction was compared based on the percent yield after spray drying. URW tablets were prepared using the dry granulation method. The optimized products were assessed using standard characterization methods based on the United States and British Pharmacopeias. DPPH and ABTS radical scavenging assays were performed to analyze the antioxidant capacity of the microwave-assisted extracts. The results revealed that the flowability of the dry granule with added maltodextrin was improved compared to a granule without additives, as indicated by an angle of repose of 33.69 ± 2.0°, a compressibility index of 15.38 ± 0.66, and a Hausner's ratio of 1.18 ± 0.06. The resulting formulation produced flat tablets with uniform weight variation, hardness, thickness, friability, and optimum disintegration time. The URW extracts showed antioxidant activity and MAE with maltodextrin carrier displayed the strongest DPPH and ABTS radical activities with IC50 values of 1.60 ± 0.02 μg/mL and 4.02 ± 0.24 μg/mL, respectively. The URW tablet formulation passed the quality control tests. Storage of the formulation tablets for 90 days under accelerated conditions had minimal effects on tablet characteristics.

Freeze-Drying Technique for Microencapsulation of Elsholtzia ciliata Ethanolic Extract Using Different Coating Materials

The present study reports on the encapsulation of Elsholtzia ciliata ethanolic extract by freeze-drying method using skim milk, sodium caseinate, gum Arabic, maltodextrin, beta-maltodextrin, and resistant-maltodextrin alone or in mixtures of two or four encapsulants. The encapsulation ability of the final mixtures was evaluated based on their microencapsulating efficiency (EE) of total phenolic compounds (TPC) and the physicochemical properties of freeze-dried powders. Results showed that the freeze-dried powders produced using two encapsulants have a lower moisture content, but higher solubility, Carr index, and Hausner ratio than freeze-dried powders produced using only one encapsulant in the formulation. The microencapsulating efficiency of TPC also varied depending on encapsulants used. The lowest EE% of TPC was determined with maltodextrin (21.17%), and the highest with sodium caseinate (83.02%). Scanning electron microscopy revealed that freeze-drying resulted in the formation of different size, irregular shape glassy particles. This study demonstrated good mucoadhesive properties of freeze-dried powders, which could be incorporated in buccal or oral delivery dosage forms. In conclusion, the microencapsulation of E. ciliata ethanolic extract by freeze-drying is an effective method to produce new value-added pharmaceutical or food formulations with polyphenols.

Design and Development of Spray-Dried Microsystems to Improve Technological and Functional Properties of Bioactive Compounds from Hazelnut Shells

An extract obtained from hazelnut shells by-products (HSE) has antioxidant and chemopreventive effects on human melanoma and cervical cancer cell lines, inducing apoptosis by caspase-3 activation. A clinical translation is limited by poor water solubility and low bioavailability. Dried plant extracts often show critical characteristics such as sticky/gummy appearance, unpleasant smell, and instability involving practical difficulties in processing for industrial use. A spray drying method has been applied to transform raw HSE in a microparticulate powder. The biopolymeric matrix was based on l-proline as loading carrier, hydroxyethylcellulose in combination with pectin as coating polymers; lecithin and ethanol were used as solubility enhancers. A Hot-Cold-Hot method was selected to prepare the liquid feed. The thus prepared powder showed good technological properties (solid-state, particle dimensions, morphology, and water dissolution rate), stability, and unchanged chemopreventive effects with respect to the unprocessed HSE.

Encapsulation of Essential Oils for the Development of Biosourced Pesticides with Controlled Release: A Review

Essential oil (EO) encapsulation can be carried out via a multitude of techniques, depending on applications. Because of EOs’ biological activities, the development of biosourced pesticides with EO encapsulation is of great interest. A lot of methods have been developed; they are presented in this review, together with the properties of the final products. Encapsulation conserves and protects EOs from outside aggression, but also allows for controlled release, which is useful for applications in agronomy. The focus is on the matrices that are of interest for the controlled release of their content, namely: alginate, chitosan, and cyclodextrin. Those three matrices are used with several methods in order to create EO encapsulation with different structures, capacities, and release profiles.