Infusion of catechin into native corn starch granules for drug and nutrient delivery systems

Physicochemical Characteristics of Porous Starch Obtained by Combined Physical and Enzymatic Methods-Part 2: Potential Application as a Carrier of Gallic Acid

Wettability measurements were performed for aqueous dispersions of native and modified corn, potato, and pea starch granules deposited on glass plates by the thin layer method using test liquids of a different chemical nature (polar water and formamide or non-polar diiodomethane). High values of the determination coefficient R2 confirm that the linear regression model describes the relationship between the wetting time and the square of the penetration distance very well, indicating the linear nature of the Washburn relationship. A change in free energy (enthalpy) during the movement of the liquid in the porous layer was determined for all starches before and after modification in contact with test liquids. Wetting times for polar liquids increased significantly (from 3 to 4 fold), especially for corn starch. The lower the value of the adhesive tension, the easier the wetting process takes place, and consequently, the adsorption process is facilitated. Adhesive tension for polar substances applies to the adsorption of hydrophilic substances, while in the case of apolar substances, adhesive tension applies to the adsorption of hydrophobic substances. For the adsorption of gallic acid on starch, the relationships obtained for polar substances are crucial. The adsorption of gallic acid by forming hydrogen bonds or, more generally, donor-acceptor (acid-base) bonds is definitely higher for corn starch than other starches. Therefore, this starch has the most significant potential for use as a carrier of gallic acid or, more broadly, compounds from the polyphenol group.

Tunable interactions in starch-anthocyanin complexes switched by high hydrostatic pressure

Native starches usually have poor polyphenol-binding efficiency despite remarkable architectural structures. In this study, the interaction between cyandin-3-O-glucose (C3G) and three starches under high hydrostatic pressure was investigated. Pressure (200-550 MPa) was found to promote the binding rate of potato starch from 31.6% to 47.0% but reduced that of corn and pea starch to below 10% at 550 MPa. Microscopy results showed that pressurized corn and pea starch-C3G complexes partially or completely lost spatial structures, whereas potato starch-C3G complexes retained structural integrity. The former had decreased zeta potentials and increased particle sizes at 550 MPa, suggesting surface charges and specific surface area losses caused poor binding. Potato starch-C3G complexes, however, exhibited unchanged zeta potential and particle size but the strongest fluorescence at 200 MPa, indicating a positive binding shift from surface to interior. Overall, high hydrostatic pressure can regulate the interactions of native starches with anthocyanins via spatial structural changes.

Sequential starch modification by branching enzyme and 4-α-glucanotransferase improves retention of curcumin in starch-alginate beads

A new super-branched amylopectin with longer exterior chains was produced from normal maize starch by modification with branching enzyme followed by 4-α-glucanotransferase, and applied for co-entrapment of a curcumin-loaded emulsion in alginate beads. The network structure of the gel beads was obtained with Ca2+-cross-linked alginate and a modest load of retrograded starch. The dual enzyme modified starch contained more and longer α-1,6-linked branch chains than single enzyme modified and unmodified starches and showed superior resistance to digestive enzymes. Alginate beads with or without starch were of similar size (1.69-1.74 mm), but curcumin retention was improved 1.4-2.8-fold in the presence of different starches. Thus, subjecting the curcumin-loaded beads to in vitro simulated gastrointestinal digestion resulted in retention of 70, 43 and 22 % of the curcumin entrapped in the presence of modified, unmodified, or no starch, respectively. Molecular docking provided support for curcumin interacting with starch via hydrogen bonding, hydrophobic contacts and π-π stacking. The study highlights the potential of utilizing low concentration of dual-enzyme modified starch with alginate to create a versatile vehicle for controlled release and targeted delivery of bioactive compounds.

Formation, Structural Characterization, and Functional Properties of Corn Starch/Zeaxanthin Composites

Zeaxanthin is a natural xanthophyll carotenoid and the main macular pigment that protects the macula from light-initiated oxidative damage, but it has poor stability and low bioavailability. Absorption of this active ingredient into starch granules as a carrier can be used to improve both zeaxanthin stability and controlled release. Optimization using three variables judged important for optimizing the system (reaction temperature of 65 °C, starch concentration of 6%, and reaction time of 2 h) was conducted for incorporation of zeaxanthin into corn starch granules, aiming for high zeaxanthin content (2.47 mg/g) and high encapsulation efficiency (74%). Polarized-light microscopy, X-ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopy showed that the process partially gelatinized corn starch; additionally, it showed the presence of corn starch/zeaxanthin composites, with the zeaxanthin successfully trapped in corn starch granules. The half-life time of zeaxanthin in corn starch/zeaxanthin composites increased to 43 days as compared with that of zeaxanthin alone (13 days). The composites show a rapid increase in zeaxanthin release with in vitro intestinal digestion, which is favorable for possible use in living systems. These findings could have application in designing effective starch-based carriers of this bioactive ingredient with enhanced storage stability and improved intestines-targeted controlled-release delivery.

Infusion efficiency of fluorescein derivatives of different molecular sizes into various starches under atmospheric and high hydrostatic pressures

Fluorescein isothiocyanate-dextrans (FDs) of different molecular weights were infused into corn, waxy rice, tapioca, and potato starches under atmospheric and high hydrostatic pressures (HHP). FD4, FD10, FD20, and FD40 (Mw 4000, 10,000, 20,000, and 40,000, respectively) were used as infusion materials. Confocal laser scanning microscopy confirmed that all FDs except FD40 infused into corn, waxy rice, and tapioca starches. However, no FDs infused into potato starch. Corn starch had the highest amounts of infused FDs. As molar mass increased, the amount of infused FD decreased in all starches. The infused amounts of FDs in corn starch were similar at 200-300 MPa and atmospheric pressure. Infusion of FDs at 400 MPa was reduced due to partial gelatinization. These results confirm that infusion efficiency is inversely proportional to the molecular weight of the infused material and large materials (Mw > 40,000) cannot be infused into starch granules under atmospheric pressure or HHP.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10068-021-00972-2.

Lipophilization and amylose inclusion complexation enhance the stability and release of catechin

Catechin is a natural phenolic compound with various bioactivities. However, it is unstable under light and heat environments. Amylose can form a single helical hydrophobic cavity to encapsulate and protect bioactive compounds. In this work, we applied amylose inclusion complexes (IC) to encapsulate a lipophilized catechin, i.e., hexadecyl catechin (HC), to improve its photostability and thermal stability. The formation of amylose-HC IC was characterized using differential scanning calorimetry, X-ray diffraction, and Fourier transform infrared spectroscopy. The photostability and thermal stability studies showed that the retention of guest molecules in IC was 86.1% ± 5.1% and 87.4% ± 0.6%, respectively, which was significantly higher than that of the catechin, HC, and amylose-HC physical mixture groups. Moreover, the in vitro release profile of IC demonstrated a steady and complete release of catechin. The findings show the amylose encapsulation of catechin is a promising technique to preserve bioactive compounds in food.

Extruded Preparations with Sour Cherry Pomace Influence Quality and Increase the Level of Bioactive Components in Gluten-Free Breads

Gluten-free bread (GFB) usually has a lower nutritional value than its traditional counterparts and is deficient in health-promoting substances. Therefore, GFB is often enriched in gluten-free components containing high levels of bioactive substances. In this work, an attempt has been made to enrich GFB with rice flour-based extruded preparations produced at 80 and 120°C with a share of 10 and 20% sour cherry pomace. The study material consisted of the abovementioned preparations together with breads produced with their 10% share. In order to prove that the extruded preparations could be the source of phenolic compounds, their level was determined. The influence of the applied additions was assessed taking into account nutritional composition (protein, fat, ash, and carbohydrates), level of the phenolic compounds (total phenolic content, flavonoids, anthocyanins, and phenolic acids), antioxidant potential, and physical properties of the breads (texture volume, color). It was shown that the extrudates with a share of fruit pomace cause an enrichment of gluten-free breads in bioactive compounds. The gluten-free breads enriched in extrudates with sour cherry pomace obtained at 120°C contained even 6 times more polyphenols than breads with extrudates obtained at 80°C. At the same time, these breads contained the highest levels of flavonoids and phenolic acids among all the analyzed samples. Bread with the addition of the extrudate produced with 20% fruit pomace at 120°C was the most favorable in terms of bioactive compounds (total phenolic content, flavonoids, anthocyanins, and phenolic acids) and antioxidative activity. The abovementioned bread showed the highest amount of total, soluble and insoluble fiber, and a significant amount of ash and sugars and revealed the lowest hardness during 3 days of storage, in comparison with the other samples.

Infusion efficiency of sodium fluorescein into various starches

The objective of this study was to develop new drug delivery systems (DDS) and nutrient delivery systems (NDS), using starch as a carrier material for infusion technology. Corn, waxy rice, non-waxy rice, and potato starches were used as carrier materials. Sodium fluorescein was used as an infusion material for easy detection. Each starch suspension with sodium fluorescein was reacted in a water bath at 40, 50, and 60 °C for 30 min. After each reaction, the concentration of sodium fluorescein in the supernatant was measured using a fluorescence detector. Precipitated starch was observed using fluorescence microscopy. About 70% of sodium fluorescein infused in waxy rice and corn starches at 60 °C. Additionally, the granules of these two starches were luminous by green light when exposed to a fluorescence detector, suggesting that corn and waxy rice starches can be used as carrier materials in infusion technology for DDS and NDS.

Encapsulation, protection, and delivery of bioactive proteins and peptides using nanoparticle and microparticle systems: A review

There are many examples of bioactive proteins and peptides that would benefit from oral delivery through functional foods, supplements, or medical foods, including hormones, enzymes, antimicrobials, vaccines, and ACE inhibitors. However, many of these bioactive proteins are highly susceptible to denaturation, aggregation or hydrolysis within commercial products or inside the human gastrointestinal tract (GIT). Moreover, many bioactive proteins have poor absorption characteristics within the GIT. Colloidal systems, which contain nanoparticles or microparticles, can be designed to encapsulate, retain, protect, and deliver bioactive proteins. For instance, a bioactive protein may have to remain encapsulated and stable during storage and passage through the mouth and stomach, but then be released within the small intestine where it can be absorbed. This article reviews the application of food-grade colloidal systems for oral delivery of bioactive proteins, including microemulsions, emulsions, nanoemulsions, solid lipid nanoparticles, multiple emulsions, liposomes, and microgels. It also provides a critical assessment of the characteristics of colloidal particles that impact the effectiveness of protein delivery systems, such as particle composition, size, permeability, interfacial properties, and stability. This information should be useful for the rational design of medical foods, functional foods, and supplements for effective oral delivery of bioactive proteins.

Insights into the structural and physicochemical properties of small granular starches from two hydrophyte duckweeds, Spirodela oligorrhiza and Lemna minor

The structure and physicochemical properties of starches from two hydrophyte duckweeds, Spirodela oligorrhiza and Lemna minor, were investigated and compared in this study. The amylose content and average size of starches were determined to be 20.85%, 4.70 μm and 27.77%, 6.17 μm for Spirodela oligorrhiza and Lemna minor, respectively. The average chain length of two duckweed starches was measured to be around DP 28. The chain length distribution was observed to be greatly different from other reported starches for the high proportion of long chains (DP ≥ 37) over 50%. Wide-angle X-ray diffraction profiles of the two starch samples displayed typical B-type diffraction pattern. The gelatinization enthalpy-changes (ΔH_gel) of two starch samples was about 10.40 J/g for two duckweed starches. The present results suggested the potential utilization of small granular starches from duckweed in functional foods and dietary supplement products.