A modified Achira (Canna indica L.) starch as a wall material for the encapsulation of Hibiscus sabdariffa extract using spray drying

Structural, morphological, compositional, thermal, pasting, and functional properties of isolated Achira (Canna indica L.) starch: Review

The aim of this study was to analyze the physicochemical properties of native Colombian Achira starch (Canna indica L.). Achira starch, with an amylose content of 49.07 % is classified as high amylose starch. Scanning electron microscopy (SEM) revealed grains with an average size of 54.34 μm in length and 34.93 μm in width, with spherical, ellipsoidal, and ovoid shapes. Mineral analysis identified phosphorus (P) and potassium (K) as the most important elements. For the first time, transmission electron microscopy (TEM) and X-ray diffraction (XRD) confirmed the presence of nanocrystals with a length of 23.95 nm, a width of 6.44 nm, and a hexagonal crystal structure (B-type starch). Thermogravimetric analysis (TGA) showed mass losses associated with water, lipids, and protein carbohydrates. Differential scanning calorimetry (DSC) showed gelatinization at 61.17 °C. The pasting profile indicated hydrogel behavior with a high peak viscosity of 13,690 cP due to the amylose content. The water absorption index (WAI) was 2.07 g/g, the water solubility index (WSI) was 3.04 g/g, and swelling power (SP) was 2.19 g/g. The presence of nanocrystals and the high amylose content indicate potential in the food industry.

Inulin as prebiotic encapsulating agent for the production of spray-dried Hibiscus sabdariffa L. tea microcapsules

Due to the high content of phenolics and anthocyanins of Hibiscus sabdariffa L. tea and the sensibility of these bioactive compounds, this work aimed to optimize the obtention of microcapsules by spray-drying, using inulin as a carrier agent. Using a Box-Behnken Design, the effects of inlet temperature (130, 150, and 170 °C), feed flow rate (5, 10, and 15 mL min-1), and inulin concentration (5, 10, and 15 g L-1) were evaluated. It was possible to obtain pale-rose, slightly sweet instant powders with good total polyphenol content (1.12 mgGAE g-1) and anthocyanins encapsulation efficiency (32.3-60.6%), besides moisture (4.61-17.79%) and water activity (0.221-0.501), indicating physico-chemical and microbiological stability of the microcapsules. A simultaneous optimization with the desirability function was performed to maximize all the response variables analyzed, and the optimum conditions of 5 g L-1 of inulin, inlet temperature of 170 °C, and feed flow rate of 83 mL min-1 were found.

Preparation and characterization of a modified Canna starch as a wall material for the encapsulation of methyleugenol improves its antifungal activity against Fusarium trichothecioides

In this study, α-amylase (α-A) and 2-octenylsuccinic anhydride (OSA)-modified Canna starch (Cs) were prepared and characterized as wall materials and encapsulated with methyleugenol (α-A-OSA-Cs-methyleugenol); their in vitro antifungal activity against Fusarium trichothecioides (F. trichothecioides) was also investigated. The encapsulation efficiency under optimal encapsulation conditions was 83.98%. The results of particle size, polydispersity index (PDI), zeta potential, electron scanning microscopy and Fourier transform infrared spectroscopy showed that the modified Cs had superior physicochemical properties; it was also demonstrated that methyleugenol successfully entered the pores of Cs. The in vitro release study showed that α-A-OSA-Cs could effectively reduce their volatility under different temperature environments. α-A-OSA-Cs have excellent performance as slow-release wall materials, and after encapsulation with methyleugenol, the inhibition ability of F. trichothecioides mycelium growth was dose-dependent and improved, extending the shelf life of potatoes, which has good commercial value in the field of slow-release preservatives.

Impact of Processing and Physicochemical Parameter on Hibiscus sabdariffa Calyxes Biomolecules and Antioxidant Activity: From Powder Production to Reconstitution

Hibiscus sabdariffa is a tropical plant with red calyxes whose anthocyanins, phenols, and antioxidant activity make it attractive to consumers both from a nutritional and medicinal standpoint. Its seasonality, perishability, and anthocyanin instability, led to the setup of stabilization methods comprising drying and powdering. However, its properties can often be altered during these stabilization processes. Treatments such as dehumidified-air-drying, infrared drying, and oven-drying, and their combination showed better quality preservation. Moreover, powder production enables superior biomolecule extractability which can be linked to a higher bioaccessibility. However, the required temperatures for powder production increase the bioactive molecules degradation leading to their antioxidant activity loss. To overcome this issue, ambient or cryogenic grinding could be an excellent method to improve the biomolecule bioavailability and accessibility if the processing steps are well mastered. To be sure to benefit from the final nutritional quality of the powder, such as the antioxidant activity of biomolecules, powders have to offer excellent reconstitutability which is linked to powder physicochemical properties and the reconstitution media. Typically, the finest powder granulometry and using an agitated low-temperature reconstitution media allow for improving anthocyanin extractability and stability. In this review, the relevant physicochemical and processing parameters influencing plant powder features from processing transformation to reconstitution will be presented with a focus on bioactive molecules and antioxidant activity preservation.

Optimization of the Spray-Drying Encapsulation of Sea Buckthorn Berry Oil

The aim of this study was to evaluate the effect of spray-drying parameters on the physicochemical properties of encapsulated sea buckthorn berry oil. Different carriers (gum arabic, β-cyclodextrin, and their mixture (1:1, w/w)), inlet air temperatures (120, 150, and 180 °C), and carrier-to-oil ratios (2, 3, and 4, w/w) were evaluated. The obtained powders were characterized in terms of the product yield (36.79-64.60%), encapsulation efficiency (73.08-93.18%), moisture content (0.23-3.70%), hygroscopicity (1.5-7.06 g/100 g), solubility (19.55-74.70%), bulk density (0.25-0.44 g/L), total carotenoid content (mg/100 g dm), and antioxidant capacity (871.83-1454.39 μmol TE/100 g dm). All physicochemical properties were significantly affected by the carrier-to-oil ratio and inlet air temperature. Higher carrier-to-oil ratios increased the product yield, encapsulation efficiency, solubility, and bulk density and decreased the powder hygroscopicity. Elevating the drying temperatures during spray drying also increased the product yield, encapsulation efficiency, and solubility, while it decreased the powder moisture content, total carotenoid content, and antioxidant capacity. Based on the physicochemical properties, the use of β-cyclodextrin as a carrier, a drying temperature of 120 °C, and a carrier-to-oil ratio of 4 were selected as optimal conditions for the production of sea buckthorn berry oil powder. The obtained powder is a valuable material for a wide range of applications in the food and nutraceutical industries.

Wall Materials for Encapsulating Bioactive Compounds via Spray-Drying: A Review

Spray-drying is a continuous encapsulation method that effectively preserves, stabilizes, and retards the degradation of bioactive compounds by encapsulating them within a wall material. The resulting capsules exhibit diverse characteristics influenced by factors such as operating conditions (e.g., air temperature and feed rate) and the interactions between the bioactive compounds and the wall material. This review aims to compile recent research (within the past 5 years) on spray-drying for bioactive compound encapsulation, emphasizing the significance of wall materials in spray-drying and their impact on encapsulation yield, efficiency, and capsule morphology.

Controlled Drug Release from Nanoengineered Polysaccharides

Polysaccharides are naturally occurring complex molecules with exceptional physicochemical properties and bioactivities. They originate from plant, animal, and microbial-based resources and processes and can be chemically modified. The biocompatibility and biodegradability of polysaccharides enable their increased use in nanoscale synthesis and engineering for drug encapsulation and release. This review focuses on sustained drug release studies from nanoscale polysaccharides in the fields of nanotechnology and biomedical sciences. Particular emphasis is placed on drug release kinetics and relevant mathematical models. An effective release model can be used to envision the behavior of specific nanoscale polysaccharide matrices and reduce impending experimental trial and error, saving time and resources. A robust model can also assist in translating from in vitro to in vivo experiments. The main aim of this review is to demonstrate that any study that establishes sustained release from nanoscale polysaccharide matrices should be accompanied by a detailed analysis of drug release kinetics by modeling since sustained release from polysaccharides not only involves diffusion and degradation but also surface erosion, complicated swelling dynamics, crosslinking, and drug-polymer interactions. As such, in the first part, we discuss the classification and role of polysaccharides in various applications and later elaborate on the specific pharmaceutical processes of polysaccharides in ionic gelling, stabilization, cross-linking, grafting, and encapsulation of drugs. We also document several drug release models applied to nanoscale hydrogels, nanofibers, and nanoparticles of polysaccharides and conclude that, at times, more than one model can accurately describe the sustained release profiles, indicating the existence of release mechanisms running in parallel. Finally, we conclude with the future opportunities and advanced applications of nanoengineered polysaccharides and their theranostic aptitudes for future clinical applications.

Optimization of spray drying process parameters for the food bioactive ingredients

Spray drying (SD) is one of the most important thermal processes used to produce different powders and encapsulated materials. During this process, quality degradation might happen. The main objective of applying optimization methods in SD processes is maximizing the final nutritional quality of the product besides sensory attributes. Optimization regarding economic issues might be also performed. Applying optimization approaches in line with mathematical models to predict product changes during thermal processes such as SD can be a promising method to enhance the quality of final products. In this review, the application of the response surface methodology (RSM), as the most widely used approach, is introduced along with other optimization techniques such as factorial, Taguchi, and some artificial intelligence-based methods like artificial neural networks (ANN), genetic algorithms (GA), Fuzzy logic, and adaptive neuro-fuzzy inference system (ANFIS). Also, probabilistic methods such as Monte Carlo are briefly introduced. Some recent case studies regarding the implementation of these methods in SD processes are also exemplified and discussed.

Effect of surfactant content on rheological, thermal, morphological and surface properties of thermoplastic starch (TPS) and polylactic acid (PLA) blends

Miscibility in biopolymeric blends is a critical process that requires evaluation of the effect of surfactants or coupling agents under conditions similar to processing. Different mixtures in the molten state of plasticized starch and polylactic acid in the presence of a surfactant (Tween 20) at different concentrations were studied. This allowed knowing the rheological, thermal and surface behavior of the mixtures. The results of the dynamic rheological analysis showed increases in viscosity in the presence of the surfactant, in which strong interactions were produced at high shear rates that reflect possible crosslinking between the polymer chains, in addition to intermolecular interactions that were evidenced in the infrared spectrum. Likewise, the storage and loss modulus showed transitions mainly from viscous to elastic typical for thermoplastics. The thermogravimetric analysis did not show significant changes between the mixtures. However, the calorimetric analysis showed changes in the crystallinity of the mixtures, the tensoactive promotes greater freedom of movement and rearrangements in the microstructure with decrease of interface between polymers, and less compaction of the material induced by the emulsion. Analysis derived from biopolymeric films against contact with water shows significant changes. Interaction with water in short times (in the order of minutes) according to the sessile drop technique, favors hydrophilicity by increasing the concentration of Tween 20. However, interaction with water for prolonged times (in the order of hours), shows that the absorption reaches saturation in samples a stabilization in the absorption is observed. The results demonstrate that the miscibility of PLA in AS was achieved in the presence of the tween, under conventional processing conditions. The stability of the different formulations allows the production of films for packaging and biomedical applications.

Encapsulation of bioactive compounds extracted from plants of genus Hibiscus: A review of selected techniques and applications

The genus Hibiscus includes more than 250 species, and many studies showed that these plants contain bioactive compounds with technological potential to be used in the development of functional foods. However, the instability of these compounds during typical food processing conditions, such as exposure to high temperatures, pH changes and presence of light and oxygen have stimulated the use of encapsulation techniques to increase their stability and applicability. Among the existing Hibiscus species, only H. sabdariffa, H. cannabinus, and H. acetosella have been investigated in encapsulation studies, being spray drying the most common method approached. Considering the high technological potential offered by the incorporation of encapsulated bioactive compounds from plants of the genus Hibiscus in food formulations, this review discusses key information of selected encapsulation techniques, which represents promising alternatives to increase food systems' stability and stimulate the design of new functional foods. Relevant gaps in the literature were also noticed, mainly the lack of systematic studies regarding the composition of bioactive compounds after encapsulation, instead of total determinations, and biological activities in different analytical systems, such as antioxidant, antimicrobial and anti-inflammatory properties as well as bioaccessibility and bioavailability.

Polysaccharide Matrices for the Encapsulation of Tetrahydrocurcumin-Potential Application as Biopesticide against Fusarium graminearum

Cereals are subject to contamination by pathogenic fungi, which damage grains and threaten public health with their mycotoxins. Fusarium graminearum and its mycotoxins, trichothecenes B (TCTBs), are especially targeted in this study. Recently, the increased public and political awareness concerning environmental issues tends to limit the use of traditional fungicides against these pathogens in favor of eco-friendlier alternatives. This study focuses on the development of biofungicides based on the encapsulation of a curcumin derivative, tetrahydrocurcumin (THC), in polysaccharide matrices. Starch octenylsuccinate (OSA-starch) and chitosan have been chosen since they are generally recognized as safe. THC has been successfully trapped into particles obtained through a spray-drying or freeze-drying processes. The particles present different properties, as revealed by visual observations and scanning electron microscopy. They are also different in terms of the amount and the release of encapsulated THC. Although freeze-dried OSA-starch has better trapped THC, it seems less able to protect the phenolic compound than spray-dried particles. Chitosan particles, both spray-dried and lyophilized, have shown promising antifungal properties. The IC₅₀ of THC-loaded spray-dried chitosan particles is as low as 0.6 ± 0.3 g/L. These particles have also significantly decreased the accumulation of TCTBs by 39%.

Innovative Delivery Systems Loaded with Plant Bioactive Ingredients: Formulation Approaches and Applications

Plants constitute a rich source of diverse classes of valuable phytochemicals (e.g., phenolic acids, flavonoids, carotenoids, alkaloids) with proven biological activity (e.g., antioxidant, anti-inflammatory, antimicrobial, etc.). However, factors such as low stability, poor solubility and bioavailability limit their food, cosmetics and pharmaceutical applications. In this regard, a wide range of delivery systems have been developed to increase the stability of plant-derived bioactive compounds upon processing, storage or under gastrointestinal digestion conditions, to enhance their solubility, to mask undesirable flavors as well as to efficiently deliver them to the target tissues where they can exert their biological activity and promote human health. In the present review, the latest advances regarding the design of innovative delivery systems for pure plant bioactive compounds, extracts or essential oils, in order to overcome the above-mentioned challenges, are presented. Moreover, a broad spectrum of applications along with future trends are critically discussed.

Nanosystems for the Encapsulation of Natural Products: The Case of Chitosan Biopolymer as a Matrix

Chitosan is a cationic natural polysaccharide, which has emerged as an increasingly interesting biomaterialover the past few years. It constitutes a novel perspective in drug delivery systems and nanocarriers' formulations due to its beneficial properties, including biocompatibility, biodegradability and low toxicity. The potentiality of chemical or enzymatic modifications of the biopolymer, as well as its complementary use with other polymers, further attract the scientific community, offering improved and combined properties in the final materials. As a result, chitosan has been extensively used as a matrix for the encapsulation of several valuable compounds. In this review article, the advantageous character of chitosan as a matrix for nanosystemsis presented, focusing on the encapsulation of natural products. A five-year literature review is attempted covering the use of chitosan and modified chitosan as matrices and coatings for the encapsulation of natural extracts, essential oils or pure naturally occurring bioactive compounds are discussed.

Microencapsulation of Rambutan Peel Extract by Spray Drying

Microencapsulation of bioactive compounds (BC) from rambutan peel by spray drying using DE10 maltodextrin as encapsulating agent was performed. The optimal conditions for the ethanolic extraction of BC were 60 °C, with a time of 1 h, 55% aqueous ethanol and three extraction cycles. The best spray drying encapsulating conditions for BC and antioxidant capacity (AC) were: inlet temperature 160 °C, outlet temperature 80 °C, and 10% encapsulating agent concentration in the feeding solution (core:encapsulating agent ratio of 1:4). With these conditions, retention and encapsulation efficiencies obtained were higher than 85%, the water activity value, moisture content and Hausner Index were of 0.25 ± 0.01, 3.95 ± 0.10%, and 1.42 ± 0.00, respectively. The optimized powder presented good solubility and morphological properties, showing microcapsules without ruptures. Based on these results, microencapsulation by spray drying is a viable technique which protects BC of rambutan peel, facilitating its application in the food, pharmaceutical, and cosmetic industries.

Use of a Taguchi Design in Hibiscus sabdariffa Extracts Encapsulated by Spray-Drying

Aqueous and ethanolic extracts of Hibiscus sabdariffa were spray-dried using maltodextrin (MD) and gum arabic (GA) as carrier agents. A Taguchi L8 experimental design with seven variables was implemented. Physicochemical properties in the encapsulates were evaluated by Ultraviolet-Visible (UV-Vis,) X-ray Diffraction (XRD), spectroscopy and gravimetric techniques. Treatments with aqueous extracts showed the highest concentration of total soluble polyphenols (TSP) 32.12-21.23 mg equivalent gallic acid (EAG)/g dry weight (DW), and antioxidant capacity (AOX) in the 2,2-azinobis-3-ethylbenzotiazoline-6-sulfonic acid (ABTS) assay. The best treatment for TSP and AOX was T4: 2.5% Hibiscus w/w, aqueous extract, decoction, extract-to-carrier ratio 1:1 (w/w), proportion to carriers (MD:GA) 80:20 (w/w), 10,000 rpm, 150 °C. The Taguchi L8 design is a tool that allows the use of multiple variables with a low number of treatments that indicate the drying conditions that give the best parameters, focusing mainly on TSP and AOX, also, it is a good alternative for the preservation and stability of the phenolic compoudns in Hibiscus.

Microencapsulation of Red Sorghum Phenolic Compounds with Esterified Sorghum Starch as Encapsulant Materials by Spray Drying

Phenolic compounds with antioxidant properties are highly sensitive molecules, which limits their application. In response, extruded esterified starch has been proposed as efficient encapsulating material. In this work, we aim to describe the encapsulation of red sorghum phenolic compounds by spray drying using extruded phosphorylated, acetylated and double esterified sorghum starch as wall material. Their respective encapsulation yields were 77.4, 67.4 and 56.8%, and encapsulation efficiency 91.4, 89.7 and 84.6%. Degree of substitution confirmed esterification of the sorghum starch and Fourier transform infrared spectroscopy showed the significant chemical and structural changes in the extruded esterified starch loaded with phenolic compounds. Microcapsules from phosphorylated sorghum starch showed the highest endothermic transition (173.89 °C) and provided a greater protection of the phenolic compounds during storage at 60 °C for 35 days than the other wall materials. Extruded esterified sorghum starch proved to be effective material for the protection of phenolic compounds due to its high encapsulation efficiency and stability during storage.