Ivona Elez Garofulić

This study evaluated the efficiency of advanced extraction techniques for recovering polyphenols from blackcurrant pomace (BP), with particular emphasis on anthocyanins. Pressurized liquid extraction (PLE), microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), and the use of cryogrinding (CG) as a pretreatment were investigated under selected experimental conditions and compared with the conventional extraction technique (CT). Among the investigated extraction techniques, UAE provided relatively high anthocyanin recovery, while CG significantly enhanced extraction efficiency. Under the investigated conditions, CT yielded the highest total phenolic content (TPC) among the extraction techniques compared, but not the highest total monomeric anthocyanin content (TMAC), whereas CG combined with UAE (CG + UAE; 2 min CG, 75% amplitude, 5 min, 1:60 g/mL) provided a favorable balance between TPC and TMAC. UPLC–ESI–MS² profiling confirmed high recovery of delphinidin- and cyanidin-based glycosides, flavonols, phenolic acids, and flavan-3-ols. The optimized extract showed strong antioxidant capacity in FRAP, DPPH, ABTS, and ORAC assays. Zebrafish embryotoxicity and cell-based assays showed concentration-dependent effects, indicating that further assessment is needed before conclusions regarding extract safety can be drawn. Overall, CG + UAE showed potential for improving the recovery of bioactive compounds from BP under the investigated conditions.

Marine-derived bioactive compounds have attracted considerable attention as functional ingredients for food and nutraceutical applications due to their various biological activities. Among marine resources, macroalgae represent a sustainable and abundant source of structurally diverse bioactive compounds, including polyphenols, pigments, and polysaccharides. This review provides a comprehensive overview of macroalgal bioactive compounds, with particular emphasis on their sources, the environmental and seasonal factors influencing their composition, chemical classification and characteristics, extraction technologies, biological properties and food and nutraceutical applications. Particularly, attention is given to the molecular mechanisms underlying their antioxidant and anti-inflammatory effects, including radical scavenging, metal chelation, modulation of endogenous antioxidant defense systems, and regulation of key signaling pathways involved in inflammation. Green extraction techniques and encapsulation strategies for improving the stability, bioavailability, and functionality of macroalgal bioactives are critically discussed. Current applications in foods and nutraceutical products are reviewed alongside the major challenges related to biomass variability, large-scale production, standardization, and regulatory compliance. Overall, macroalgal bioactive compounds represent a promising class of sustainable health-promoting ingredients, and continued advances in cultivation, processing, extraction technologies, formulation, and regulatory frameworks will be essential to support their broader industrial utilization.

Black chokeberry (Aronia melanocarpa L.) pomace (BCP), a major by-product of juice production, is an underutilized source of polyphenols and anthocyanins with strong antioxidant properties. This study aimed to optimize and compare three green extraction techniques—pressurized liquid extraction (PLE), microwave-assisted extraction (MAE), and ultrasound-assisted extraction (UAE)—for recovering total polyphenols (TP) and total monomeric anthocyanins (TMA) from BCP, with reflux extraction as a benchmark. The effects of temperature, extraction time, and solid–solvent ratio were evaluated, and cryogrinding was assessed as a pre-treatment. PLE achieved the highest TP yields at elevated temperatures but reduced anthocyanin recovery, while MAE offered a balance of high TP and TMA, with strong antioxidant capacity. Cryogrinding enhanced TP extraction, with only 1 min of cryogrinding maximizing yield. UPLC-MS/MS analysis of optimized MAE extract confirmed cyanidin-3-glucoside and cyanidin-3-galactoside as dominant anthocyanins, alongside notable flavonols and phenolic acids, validating the rich phenolic profile. Overall, MAE combined with 1 min of cryogrinding proved to be the most effective approach for preserving heat-sensitive compounds while achieving high yields. These findings demonstrate that optimized green extraction can efficiently valorize BCP, supporting sustainable food processing and waste reduction in line with circular economy principles.

The increased production of high-quality berry products in recent years has led to considerable quantities of by-products such as pomace (25–50%), which consists of skin, seeds, stems and leaves. The improper management of pomace can lead to environmental pollution and potential public health problems due to microbial contamination, and storage causes additional processing costs. However, due to their high content of various valuable bioactive compounds (BACs), berry by-products have gained much attention as sustainable and functional ingredients with applications in the food and nutraceutical industries. The health benefits are primarily attributed to the phenolic compounds, which exhibit numerous biological activities, especially good antioxidant and antibacterial activity as well as health-promoting effects. This review summarizes the bioactive content and composition of extracts from berry by-products (genera Ribes, Rubus, Fragaria, Sambucus, Aronia and Vaccinium) obtained using advanced extraction technologies and their stabilization through sophisticated encapsulation technologies that make them suitable for various food applications. The addition of berry pomace to beverages, bakery, dairy and meat products improves sensory quality, extends shelf life, increases nutritional value and reduces the environmental footprint. This information can provide food scientists with valuable insights to evaluate the potential of berry by-products as functional ingredients with health-promoting and disease-preventing properties that create value-added products for human consumption while reducing food waste.

The aim of this study was to determine the retention of fatty acids, α-tocopherol, and carotenoids in sea buckthorn oil (SBO) encapsulated with gum arabic (GA), β-cyclodextrin (β-CD), and their mixture (1:1) under pre-optimized spray drying conditions in comparison to the bioactive molecule (BAM) content of the non-encapsulated oil. In addition, the color parameters in the spray-dried powders and the bioaccessibility of β-carotene, which has the highest provitamin A activity, were evaluated. The fatty acid content remained almost unchanged, while statistically significant differences in α-tocopherol and carotenoid content were found between the SBO encapsulated with different carriers and the non-encapsulated oil. The retention of tocopherols and carotenoids compared to the non-encapsulated SBO ranged from 62.13 to 87.23% and from 21.17 to 97.61%, respectively. SBO encapsulated with β-CD showed significantly higher retention of α-tocopherol (87.23%) and individual carotenoids (40.71–97.61%). In addition, the powders showed no significant differences in color parameters, and the powders encapsulated with GA and β-CD showed high bioaccessibility of β-carotene (92.50 and 90.45%, respectively). β-CD proved to be the most suitable carrier for the encapsulation of the carotenoids and α-tocopherol of SBO, resulting in powders with high bioaccessibility of β-carotene.

To determine the optimal conditions of pressurized liquid extraction (PLE) and microwave-assisted extraction (MAE) of polyphenols from black chokeberry leaves (BCL), temperature, time and sample-to-solvent ratio (SSR) were varied to obtain maximum polyphenols yield. The extracts were analyzed for total polyphenols (TP) as well as individual ones (UPLC ESI MS²) and antioxidant capacity (FRAP, DPPH and ORAC). Moreover, the biological activity of the selected extracts was additionally determined. The optimal PLE and MAE conditions were 150 °C, 5 min extraction time and SSR 1:30 g/mL (TP 80.0 mg GAE/g dm), and 70 °C, extraction time 5 min and SSR 1:30 g/mL (TP 36.4 mg GAE/g dm), respectively. Both methods yielded similar polyphenol profiles (43 compounds) but differed quantitatively. MAE extracts contained more flavonols and phenolic acids, while PLE extracts had higher procyanidins and flavan-3-ols. Furthermore, the PLE extract exhibited a superior antioxidant capacity. This BCL extract also showed that it can protect against oxidative and DNA damage and can induce free radical formation and DNA damage, albeit at different doses. Moreover, it had a moderate antimicrobial activity against S. aureus and B. subtilis, while no antimicrobial activity was observed against Gram-negative bacteria as well as yeasts, lactic acid bacteria and molds.

This study aimed to determine the optimal pressure and temperature for the maximum extraction yield and recovery of lipophilic bioactive compounds (BACs) during the supercritical carbon dioxide extraction (SCO₂) of fennel seeds. For this purpose, the SCO₂ pressure (78.6–361.4 bar) and temperature (35.9–64.1 °C) were varied and optimized, and all of the extracts obtained were analyzed for the volatiles, fatty acids, sterols, tocochromanols and carotenoids. The results showed that the maximum extract yield and content of all of the compounds analyzed favored a higher pressure (320 bar) and lower temperature (40 °C), except for the volatiles, which were the highest at 120 bar and 42 °C. However, the optimal SCO₂ conditions for obtaining the highest overall total lipophilic fraction were 320 bar and 40 °C, respectively. The fennel SCO₂ extract obtained under these conditions contained 18 volatiles (trans-anethole as the major component), 12 fatty acids (oleic and petroselinic as the major compounds), 12 sterols (β-sitosterol and stigmasterol as the major compounds), two pentacyclic triterpenoids (α-, β-amyrin), one tocopherol (α-tocopherol), two tocotrienols (γ-, δ-tocotrienol) as well as two carotenoids (lutein and β-carotene). The SCO₂ proved to be very efficient for the isolation of various lipophilic BACs from fennel, and the results of this study may be of interest to academia and industry.

Banana peels, comprising about 35% of the fruit’s weight, are often discarded, posing environmental and economic issues. This research focuses on recycling banana peel waste by optimizing advanced extraction techniques, specifically microwave-assisted (MAE) and ultrasound-assisted extraction (UAE), for the isolation of phenolic compounds. A choline chloride-based deep eutectic solvent (DES) with glycerol in a 1:3 ratio with a water content of 30% (w/w) was compared to 30% ethanol. Parameters, including sample-to-solvent ratio (SSR), extraction time, and temperature for MAE or amplitude for UAE, were varied. Extracts were analyzed for hydroxycinnamic acid (HCA) and flavonoid content, and antioxidant activity using FRAP and ABTS assays. DES outperformed ethanol, with HCA content ranging from 180.80 to 765.92 mg/100 g and flavonoid content from 96.70 to 531.08 mg/100 g, accompanied by higher antioxidant activity. Optimal MAE conditions with DES were an SSR of 1:50, a temperature of 60 °C, and a time of 10 min, whereas an SSR of 1:60, time of 5 min, and 75% amplitude were optimal for UAE. The polyphenolic profile of optimized extracts comprised 19 individual compounds belonging to the class of flavonols, flavan-3-ols, and phenolic acids. This study concluded that DESs, with their superior extraction efficiency and environmental benefits, are promising solvents for the extraction of high-value bioactive compounds from banana peels and offer significant potential for the food and pharmaceutical industries.

Fennel essential oil (EO) is well known for its biological activities and wide potential for use in the food, cosmetic, and pharmaceutical industries, where the main challenge is to achieve higher stability of EO. This study aimed to evaluate the potential of electrostatic extrusion for encapsulation of fennel EO by examining the effects of alginate (1%, 1.5%, and 2%) and whey protein (0%, 0.75%, and 1.5%) concentrations and drying methods on the encapsulation efficiency, loading capacity, bead characteristics, and swelling behavior of the produced fennel EO microbeads. Results revealed that electrostatic extrusion proved to be effective for encapsulating fennel EO, with whey protein addition enhancing the examined characteristics of the obtained microbeads. Freeze-drying exhibited superior performance compared to air-drying. Optimal encapsulation efficiency (51.95%) and loading capacity (78.28%) were achieved by using 1.5% alginate and 0.75% whey protein, followed by freeze-drying. GC-MS analysis revealed no differences in the qualitative aspect of the encapsulated and initial EO, with the encapsulated EO retaining 58.95% of volatile compounds. This study highlighted the potential of electrostatic extrusion using alginate and whey protein as a promising technique for fennel EO encapsulation while also emphasizing the need for further exploration into varied carrier materials and process parameters to optimize the encapsulation process and enhance product quality.

Carob (Ceratonia siliqua L.) is a widely spread Mediterranean evergreen tree whose plant parts are rich in bioactive compounds with potential for application in functional food production. Carob leaves are the least explored part of the plant, and the main compounds of interest are polyphenols. Advanced extraction techniques, such as pressurized liquid (PLE), microwave-assisted (MAE) and ultrasound-assisted (UAE) extraction have not been sufficiently explored for their potential in extracting these compounds. Therefore, the aim of this paper was to optimize the parameters (temperature and time) of PLE, MAE and UAE of carob leaf polyphenols, characterize the individual compounds by ultra-high performance liquid chromatography tandem mass spectrometry (UPLC-MS²) and determine the antioxidant activity of the extracts. The optimal temperature and time were 160 °C/5 min for PLE, resulting in a total phenolic content of 68.21 mg of gallic acid equivalents (GAE) g⁻¹. For MAE and UAE, the optimal conditions were 70 °C/10 min, under which total phenolic contents of 78.80 and 55.98 mg GAE g⁻¹ were achieved, respectively. A total of 26 compounds, represented mainly by myricetin, quercetin-3-rhamnoside and gallic acid, were identified in extracts obtained by all three extraction techniques. All extracts showed high antioxidant activity (0.46–1.05 and 0.50–0.58 mmol TE g⁻¹ for FRAP and DPPH, respectively), which correlated with the polyphenolic content and was affected by the concentration of ascorbic acid (0.03–0.52 mg mL⁻¹), confirming that carob leaf extracts obtained by advanced extraction possess high potential for application in functional food products.