Dry Dosage Forms of Add-Value Bioactive Phenolic Compounds by Supercritical CO2-Assisted Spray-Drying

Abstract

Every year, grapevine pruning produces huge amounts of residue, 90% of which are from vine shoots. These are a rich source of natural antioxidants, mostly phenolic compounds, which, when properly extracted, can give rise to added-value products. However, their lack of solubility in aqueous media and high susceptibility to thermal and oxidative degradation highly limit their bioavailability. Encapsulation in suitable carriers may have a positive impact on their bioavailability and bioactivity. Previous data on vine-shoot extraction have identified gallic acid (GA) and resveratrol (RSV) as the main phenolic compounds. In this work, model dry powder formulations (DPFs) of GA and RSV using hydroxypropyl cellulose (HPC) as carriers were developed using Supercritical CO2-Assisted Spray Drying (SASD). A 32 full factorial Design of Experiments investigated the solid and ethanol contents to ascertain process yield, particle size, span, and encapsulation efficiency. Amorphous powder yields above 60%, and encapsulation efficiencies up to 100% were achieved, representing excellent performances. SASD has proven to be an efficient encapsulation technique for these phenolic compounds, preserving their antioxidation potential after three months in storage with average EC50 values of 30.6 µg/mL for GA–DPFs and 149.4 µg/mL for RSV–DPF as assessed by the scavenging capacity of the DPPH radical.

Physicochemical Characterization and Evaluation of Gastrointestinal In Vitro Behavior of Alginate-Based Microbeads with Encapsulated Grape Pomace Extracts

“…During encapsulation, a change in the crystalline structure of the active compound is possible; in most cases it is an amorphization, which has been confirmed in many articles [ 97 , 98 , 99 , 100 ]. In the XRPD analysis, the GPE showed peaks at 2θ from 14° to 39°, indicating a crystalline structure ( Figure 4 ).…”

In Vitro Bioaccessibility Assessment of Phenolic Compounds from Encapsulated Grape Pomace Extract by Ionic Gelation

“…Also evident from the DSC curves are slightly broad peaks for the coating and microbeads, indicating water loss, and for the extract, an endothermic peak is visible with a transition at 268.63 • C, indicating melting of the PRE. Many studies have confirmed these changes from crystalline to amorphous structure during encapsulation [43,44]. Indeed, this change plays an important role in the digestibility of the PRE, since the extract in crystalline form is less available for absorption due to the reduced possibility of passage through the intestinal membrane.…”

Marine Bioactive Peptides: Anti-Photoaging Mechanisms and Potential Skin Protective Effects

“…Moreover, the viability of their application is further compromised by the potential generation of degradation products during the extraction process. As scientific and technological advancements continue to unfold, numerous intricate extraction and purification methodologies have been developed and implemented, such as supercritical fluid extraction (SFE) [139], subcritical water extraction (SCW) [140], pulsed electric fields (PEFs) [140], and molecular imprinting technology (MIT) [141]. These technologies provide enhanced functionalities by mitigating the constraints of conventional extraction methods.…”