Determination of Suitable Macroporous Resins and Desorbents for Carnosol and Carnosic Acid from Deep Eutectic Solvent Sage (Salvia officinalis) Extract with Assessment of Antiradical and Antibacterial Activity

An overview of hydrophobic deep eutectic solvents driven liquid-phase extraction: Applications and prospects

Deep eutectic solvents (DESs) are a type of emerging green solvent. They are simple to prepare, cost-effective, highly atom-efficient, exhibit extremely low toxicity, and are biodegradable. Since their discovery, DESs have attracted significant interest from the scientific community across various fields. In recent years, these solvents have been extensively studied by researchers as extraction media. Hydrophobic deep eutectic solvents (hDESs) first appeared in the literature in 2015 and represent a group of DESs that meet the requirements of green chemistry. hDESs have great potential in the fields of separation and extraction and are considered effective alternatives to replace hydrophilic DESs and other hydrophobic organic solvents for the extraction of lipophilic natural products. This review summarizes pioneering and innovative work on hDESs, including the latest research progress regarding their applications, extraction techniques, and recycling methods. It also highlights issues that need to be addressed in the future. The results of hDESs in natural product extraction and the extraction of other compounds have revealed their significant potential as alternative green solvents in industrial separation processes.

Recovery of Natural Hypoglycemic Compounds from Industrial Distillation Wastewater of Lamiaceae

The food industry generates the largest number of valuable by-products. The recovery of compounds such as fatty acids and polyphenols with notorious biological properties from biowaste is a new challenge in the circular economy scenario, as they represent value-added starting materials for the preparation of functional foods, food supplements, cosmetics and over-the-counter drugs. Less commonly explored are industrial wastewaters, which return to the nearby water streams without adequate treatment. Distillation wastewater (DWW) from the essential oils or agro-food industries may represent a valuable source of bioactive compounds to be valorized. In this work, DWW from rosemary was treated with different resins through dynamic and static adsorption/desorption approaches, for the recovery of phenolic compounds including rosmarinic acid. The most effective methodology, selected according to total phenolic and rosmarinic acid contents, as well as antioxidant activity evaluation, was applied to sage, thyme and oregano DWWs. The procedure provides several advantages compared with conventional separation processes, as it involves the lower consumption of reagents/solvents, low operational costs, ease of handling, and simplicity of scale-up. The results of this work highlight a fast and sustainable procedure for the recovery of rosmarinic acid and other phenolics (caffeic acid derivatives and flavonoid glycosides) from DWWS, thus affording a fraction with antioxidant and hypoglycemic activities.

Recovery of Bioactive Compounds from the Biomass of Aromatic Plants After Distillation Using NADES: A Sustainable Alternative Extraction Method

The extraction processes for medicinal plants, particularly the distillation of aromatic plants, generate significant quantities of by-products, consisting of fibrous biomass and hydrosols. These by-products pose challenges for disposal and recovery. Consequently, it is imperative to make the entire highly energy-intensive process more sustainable by valorizing all derivatives. This study aims to recover polyphenols from the exhausted biomasses of Artemisia dracunculus, Echinacea purpurea, Helichrysum italicum (from the Asteraceae family), and Lavandula angustifolia, Lavandula × intermedia, Melissa officinalis, Salvia officinalis, Salvia sclarea, and Salvia rosmarinus (from the Lamiaceae family) after steam distillation. The residual biomasses were extracted using ethanol (conventional solvent) and different natural deep eutectic solvents (NADES) composed of choline chloride in combination with citric and lactic acids at different molar ratios. The NADES containing choline chloride and lactic acid at the molar ratio 1:1 (CLA11) exhibited the highest recovery of representative phenols of the plants, namely chicoric and rosmarinic acids. The CLA11 solvent demonstrated a stronger extractive capacity compared to ethanol in all the biomasses belonging to the Asteraceae and Lamiaceae families. Specifically, CLA11 extracts showed a higher number of compounds in UHPLC-HRMS and greater concentrations of chicoric and rosmarinic acids determined by HPLC-DAD than ethanol extracts. In conclusion, NADES were demonstrated to be a viable alternative system for the recovery of bioactive compounds that could be used to formulate new products for the food, pharmaceutical, and cosmetic industries. Moreover, the use of NADES can enhance the sustainability of the whole production chain of essential oils being environmentally friendly.

Green Extraction of Phenolic Compounds from Aronia melanocarpa Using Deep Eutectic Solvents and Antioxidant Activity Investigation

This study explores the green extraction of phenolic antioxidants from Aronia melanocarpa fruit using choline-chloride-based deep eutectic solvents (DESs) as an eco-friendly alternative to conventional solvents. Sixteen DESs, prepared by combining choline chloride with various hydrogen bond donors, were characterized for their physical properties, including viscosity, polarity, and pH, and applied to extract phenolics from Aronia melanocarpa. High-performance liquid chromatography (HPLC) quantified key phenolic compounds, including neochlorogenic and chlorogenic acid, quercetin derivatives, and cyanidin derivatives, as well as total phenolic acids, flavanols, and anthocyanins. The results revealed that DES composition and physical properties significantly influenced extraction efficiency and antioxidant activity. Additionally, the intrinsic antioxidant activity of DESs contributed substantially to the overall activity of the extracts, particularly in DESs containing organic acids or thiourea. Choline chloride/tartaric acid DES demonstrated the highest total phenolic content, attributed to its high viscosity and strongly acidic pH, while choline chloride/thiourea DES, with low viscosity and slightly acidic pH, exhibited the greatest antioxidant activity. This study highlights how tailoring DES formulations can optimize the extraction of target compounds while accounting for the solvent's intrinsic properties. The findings support the potential application of DESs as environmentally friendly solvents in the food, pharmaceutical, and cosmetic industries.

Life cycle assessment and yield to optimize extraction time and solvent: Comparing deep eutectic solvents vs conventional ones

Deep eutectic solvents (DES) are gaining interest as eco-friendly alternatives for extracting bioactive compounds, but their environmental benefits remain unclear and need further evaluation. In this work, a case study of total polyphenols (TPC) extraction from spent coffee grounds (SCG) was environmentally evaluated using life cycle assessment (LCA). First, the most convenient extraction time (1, 10, 20, or 40 min) for water and acetone 20 % from an environmental perspective was identified. Second, a comparison of different solvents-DES (choline chloride-1,6-hexanediol), water, and ethanol 20 %-under their optimal extraction yield conditions was performed using literature data. Results from the first study revealed that the environmentally optimal extraction time (10 min) was not the one leading to the highest yield. The main contributors to the impacts were the use of acetone and electricity consumption. For the second study, DES performed worse in all studied environmental impact categories compared to both ethanol 20 % and water. Ethanol 20 % was the better option compared to water due to its higher extraction yield (9.2 mg vs. 6.5 mg TPC/g SCG, respectively). The environmental impacts associated with the DES system were primarily attributed to the DES preparation step, which requires virgin raw materials (e.g., dimethyl hexanediol), and the adsorption stage involving the use of resins. A sensitivity analysis was also conducted by optimizing the DES system to the best possible described conditions (90 % reuse of DES and maximum reduction of the macroporous resin used to adsorb the TPC after extraction). Nevertheless, the DES system still performed worse than water or ethanol 20 % systems, in 11 out of 16 impact categories. The study highlights the importance to consider environmental impacts and yield when optimizing extraction processes, especially at the laboratory scale, as the insights gained are valuable for improving eco-efficiency on an industrial scale.

Exploring the Antibacterial Potential of Lamiaceae Plant Extracts: Inhibition of Bacterial Growth, Adhesion, Invasion, and Biofilm Formation and Degradation in Pseudomonas aeruginosa PAO1

In response to the global rise in antibiotic resistance and the prevalence of bacterial biofilm-related infections, the antibacterial efficacy of methanolic, ethanolic, and aqueous extracts of 18 Lamiaceae plants from Serbia was evaluated. The total coumarins and triterpenes were detected spectrophotometrically, while a microdilution assay measured their effects on bacterial growth. Additionally, the impact of these extracts was assessed on Pseudomonas aeruginosa PAO1 adhesion and invasion in human fibroblasts and biofilm formation and degradation. The alcoholic extracts had the highest phytochemical content, with Teucrium montanum and Lavandula angustifolia being the richest in coumarins and triterpenes, respectively. Gram-positive bacteria, particularly Bacillus subtilis, were more susceptible to the extracts. Hyssopus officinalis ethanolic and Sideritis scardica methanolic extracts inhibited bacterial growth the most efficiently. Although the extracts did not inhibit bacterial adhesion, most ethanolic extracts significantly reduced bacterial invasion. Origanum vulgare and H. officinalis ethanolic extracts significantly inhibited biofilm formation, while Teucrium chamaedrys extract was the most active in biofilm degradation. This study significantly contributes to the literature by examining the antibacterial activity of Lamiaceae extracts, addressing major literature gaps, and underscoring their antibacterial potential, particularly Satureja montana and O. vulgare ethanolic extracts, linking their efficacy to coumarins and triterpenes.

Recovery and separation of glycyrrhizic acid from Natural Deep Eutectic Solvent (NADES) extract by macroporous resin: adsorption kinetics and isotherm studies

Natural Deep Eutectic Solvents (NADESs) have emerged as a green and sustainable alternative to conventional organic solvents to extract bioactive compounds. However, the recovery of bioactive compounds from the NADES extracts is challenging, restricting their large-scale applications. The present work investigated the recovery of glycyrrhizic acid (GA) from choline-chloride/lactic acid NADES extract using macroporous resins. GA possesses a wide spectrum of biological activities, and it is extracted from the well-known herb Glycyrrhiza glabra. During resin screening, DIAIONTM SP700 showed high adsorption and desorption capacities. The adsorption kinetics study demonstrated that the adsorption of GA on SP700 followed Pseudo First-order kinetic model. Moreover, the adsorption behaviors were elucidated by the Freundlich isotherm using a correlation coefficient based on a static adsorption study at different temperatures and pH. Furthermore, the thermodynamic parameters, for instance, the change of Gibbs free energy (ΔG*), entropy (ΔS*), and enthalpy (ΔH*), showed that the adsorption process was spontaneous, favorable and exothermic. In addition, the sample after macroporous resin treatment, which is enriched with GA exhibited good anticancer potential analyzed by SRB assay. The regenerated NADES solvent was recycled twice, keeping more than 90% extraction efficiency, indicating good reusability of NADES in the GA extraction process by using macroporous resin.

Rosemary: Unrevealing an old aromatic crop as a new source of promising functional food additive-A review

Rosemary (Rosmarinus officinalis L.) is one of the most famous spice plants belonging to the Lamiaceae family as a remarkably beautiful horticultural plant and economically agricultural crop. The essential oil of rosemary has been enthusiastically welcome in the whole world for hundreds of years. Now, it is wildly prevailing as a promising functional food additive for human health. More importantly, due to its significant aroma, food, and nutritional value, rosemary also plays an essential role in the food/feed additive and food packaging industries. Modern industrial development and fundamental scientific research have extensively revealed its unique phytochemical constituents with biologically meaningful activities, which closely related to diverse human health functions. In this review, we provide a comprehensively systematic perspective on rosemary by summarizing the structures of various pharmacological and nutritional components, biologically functional activities and their molecular regulatory networks required in food developments, and the recent advances in their applications in the food industry. Finally, the temporary limitations and future research trends regarding the development of rosemary components are also discussed and prospected. Hence, the review covering the fundamental research advances and developing prospects of rosemary is a desirable demand to facilitate their better understanding, and it will also serve as a reference to provide many insights for the future promotion of the research and development of functional foods related to rosemary.

The Selective Separation of Carnosic Acid and Rosmarinic Acid by Solid-Phase Extraction and Liquid-Liquid Extraction: A Comparative Study

Rosmarinus officinalis leaves (ROLs) are widely used in the food and cosmetics industries due to their high antioxidant activity and fascinating flavor properties. Carnosic acid (CA) and rosmarinic acid (RA) are regarded as the characteristic antioxidant components of ROLs, and the selective separation of CA and RA remains a significant challenge. In this work, the feasibility of achieving the selective separation of CA and RA from ROLs by solid-phase extraction (SPE) and liquid-liquid extraction (LLE) was studied and compared. The experiments suggested that SPE with CAD-40 macroporous resin as the adsorbent was a good choice for selectively isolating CA from the extracts of ROLs and could produce raw CA with purity levels as high as 76.5%. The LLE with ethyl acetate (EA) as the extraction solvent was more suitable for extracting RA from the diluted extracts of ROLs and could produce raw RA with a purity level of 56.3%. Compared with the reported column chromatography and LLE techniques, the developed SPE-LLE method not only exhibited higher extraction efficiency for CA and RA, but can also produce CA and RA with higher purity.

LC-MS metabolomics profiling of Salvia aegyptiaca L. and S. lanigera Poir. with the antimicrobial properties of their extracts

BACKGROUND

Salvia L. (Lamiaceae) found in almost all countries in temperate and tropical regions. Both S. aegyptiaca L. and S. lanigera Poir. have a rather wide distribution in Egypt (Mediterranean region, Gebel Elba and nearly the whole Sinai). Salvia species showed antibacterial and antifungal activities against several groups of food microorganisms and pathogens, so they are considered as a natural foods preservatives.

AIM

Investigate the phytochemical profiles of S. aegyptiaca & S. lanigera collected from their natural habitats in Egypt and test the antimicrobial activities of both species against some bacteria and fungi pathogenic strains.

METHODOLOGY

In the present study, S. aegyptiaca and S. lanigera were collected from their natural habitat. Total phenolics and flavonoids contents were measured for aerial parts of both Salvia spp.. The separation and identification of the pure active materials of both Salvia sp. by using LC-MS system (UHPLC-TSQ Quantum Mass Spectrometer). The antimicrobial activities of the ethanol, water and benzene extracts of the two species were tested against different pathogenic strains and compared with the standard antimicrobial drug (Gentamycin). Antimicrobial activity was determined by using agar disk diffusion method.

RESULTS

The phenolics content in S. lanigera 132.61±6.23 mg/g and S. aegyptiaca 125.19±4.97 mg/g, while the flavonoids content was 35.68±1.84 and 40.63±2.11 mg/g, respectively. Through LC-MS analysis, two compounds were detected in both species; heptadecanoyl coenzyme A, that the highest percentage (13.5%) in S. aegyptiaca and (11.5 %) in S. lanigera. Oenin, in a peak area of 3.1% in S. aegyptiaca and 1.2 % in S. lanigera. Ethanol extract of the two species had the most inhibitory effect against all tested microorganisms that exceeded the effect of the standard, except for Mucor reinelloids which was more sensitive to the water extract. Moreover, S. lanigera ethanol extract showed larger inhibition zone than S. aegyptiaca in all tested microorganisms except for Pseudomonas aeruginosa.

CONCLUSION

This study shows the important phytochemicals that improve the antibacterial and antifungal activities of Salvia aegyptiaca and S. lanigera.

Optimization of Deep Eutectic Solvent Extraction of Phenolic Acids and Tannins from Alchemilla vulgaris L

Alchemilla vulgaris L. is a good source of antioxidant components with an emphasis on phenolic acids and tannins. In this study, gallic acid, ellagic acid, and hydrolyzable tannins (HT) were extracted from this plant with different deep eutectic solvents (DESs), varying the amount of added H2O, temperature and extraction time. Seventeen DESs (n = 3) were used for the extraction, of which choline chloride:urea (1:2) proved to be the most suitable. The selection of the best solvent was followed by the examination of the influence of the extraction type and parameters using response surface methodology (RSM). Gallic acid content was in the range of 0.00-1.89 µg mg-1, ellagic acid content was 0.00-12.76 µg mg-1 and hydrolyzable tannin (HT) content was 3.06-181.26 µgTAE mg-1, depending on the used technique and the extraction conditions. According to the results, extraction by stirring and heating was the most suitable since the highest amounts of gallic acid, ellagic acid, and HT were extracted, and the obtained optimal values using response surface methodology (RSM) are confirmed by experimentally obtained values.

Current extraction, purification, and identification techniques of tea polyphenols: An updated review

Tea, as a beverage, has been reputed for its health benefits and gained worldwide popularity. Tea polyphenols, especially catechins, as the main bioactive compounds in tea, exhibit diverse health benefits and have wide applications in the food industry. The development of tea polyphenol-incorporated products is dependent on the extraction, purification, and identification of tea polyphenols. Recent years, many green and novel extraction, purification, and identification techniques have been developed for the preparation of tea polyphenols. This review, therefore, introduces the classification of tea and summarizes the main conventional and novel techniques for the extraction of polyphenols from various tea products. The advantages and disadvantages of these techniques are also intensively discussed and compared. In addition, the purification and identification techniques are summarized. It is hoped that this updated review can provide a research basis for the green and efficient extraction, purification, and identification of tea polyphenols, which can facilitate their utilization in the production of various functional food products and nutraceuticals.