Spray-drying Microencapsulation of an Extract from Tilia tomentosa Moench Flowers: Physicochemical Characterization and in Vitro Intestinal Activity

Abstract

Silver linden (Tilia tomentosa Moench, TtM) flowers possess several health-promoting properties, especially at the neurological level, such as intestinal relaxation activity associated with specific flavonols, particularly quercetin and kaempferol derivatives. However, such molecules are susceptible to degradation upon different triggers like heat, light and extreme pH values. To overcome the scarce stability of TtM flowers bioactive molecules and make them suitable for developing functional food and supplements, we applied microencapsulation. Spray-drying microencapsulation of TtM flowers extract was performed using three starch-derived wall materials: maltodextrin 12 DE (MD12) and 19 DE (MD19), and OSA-modified starch (OSA-S). The stability of total phenols, flavanols, and antioxidant capacity was monitored for 70 days under accelerated stress conditions (40 °C/70% RH) by HPLC and spectrophotometric methods, and the intestinal contractile activity was tested in a murine model. In comparison to MD12 and MD19, OSA-S stood out for the higher encapsulation efficiency of quercetin and kaempferol glycosides (+ 36–47% compared to MD12 and + 18–24% compared to MD19) and stability thereof (half-life on average + 30% compared to MD12 and + 51% compared to MD19). The intestinal contractile activity of OAS-S powders resulted comparable to the original extract, indicating that flavonols were biologically active and accessible. Our results underly the potential advantages of OSA-S encapsulated formulation as a functional ingredient for the development of nutraceutical products.

Spasmolytic, Antimicrobial, and Antioxidant Activities of Spray-Dried Extracts of Gentiana asclepiadea L. with In Silico Pharmacokinetic Analysis

“…This finding is significant from a pharmaceutical-technological perspective since the microencapsulated extract is preferable to traditional, commonly used tinctures, particularly in terms of protecting the stability of active compounds [ 18 ]. In line with our findings, Mainente et al (2022) reported that the microencapsulated extract of Tilia tomentosa flowers exhibited slightly weaker in vitro inhibitory activity on ileal motor functions compared to the non-encapsulated form, although the difference was comparable [ 25 ]. The rationale for microencapsulation is based on the maintenance of extract bioactivities, along with providing additional positive quality parameters for the final products.…”

Nanoencapsulation of Anthocyanins from Red Cabbage (Brassica oleracea L. var. Capitata f. rubra) through Coacervation of Whey Protein Isolate and Apple High Methoxyl Pectin

“…A complex interplay of different factors, including the degree of glycosylation and/or acylation, appears to affect the affinity of each ACN to the polymers of the coacervates and, in turn, the overall encapsulation efficiency and stability of the molecules. Indeed, as we recently described for silver linden ( Tilia tomentosa ) flavonoids, the stability of encapsulated molecules is positively influenced by the interaction with the matrix [ 44 ]. To the best of our knowledge, this is the first time that the loading of a coacervate with a complex phenolic mixture is characterised at the single-molecule level.…”

Effect of temperature and packaging materials on the shelf-life stability and in vitro properties of microencapsulated and spray-dried synbiotic legume-based instant beverage powder

“…Among different drying techniques, spray drying is one of the most widely used processes for liquid food products at a commercial scale which also allows the scope for encapsulating beneficial microorganisms such as probiotics. 15 Nonetheless, the high drying temperatures in spray drying decreases probiotic viability and also causes a glassy state in the developed powder. Spray drying is also limited to liquid food products, thereby restricting the use of this technique for a variety of food products.…”