Optimization of Supercritical Carbon Dioxide Extraction of Bioactive Flavonoid Compounds from Spearmint (Mentha spicata L.) Leaves by Using Response Surface Methodology

A new and highly efficient source of t-resveratrol: Cephalaria Syriaca (L.) Roem. & Schult

Recently, interest in bioactive plant compounds has increased due to their properties in preventing and treating diseases like cancer and neurodegenerative disorders. In this study, caffeic acid and t-resveratrol were extracted from Cephalaria syriaca seeds using ultrasonic assisted extraction (UAE) and supercritical carbon dioxide (Sc-CO2) extraction methods. Independent variables were temperature (40, 60, 80 °C), pressure (130, 215, and 300 bar), and co-solvent ratio (ethanol v/v (3.0, 6.5, 10.0%)) were selected. While extraction process conditions were optimized using response surface methodology, polyphenols were determined by an HPLC system. As a result of the Sc-CO2 experimental studies, maximum caffeic acid (88.75 ± 1.71 μg/g dw) was obtained at 80 °C, 130 bar, and 10% ethanol conditions and maximum t-resveratrol (2949.45 ± 51.78 μg/g dw) was obtained at 60 °C, 130 bar, and 6.5% ethanol conditions. The results of the UAE method were found to be 76.21 ± 2.40 μg/g dw caffeic acid and 4629 ± 123.2 μg/g dw t-resveratrol.

Bioactive properties of spearmint, orange peel, and baby sage oleoresins obtained by supercritical CO2 extraction and their integration into dark chocolate

This study investigated the potential health benefits of spearmint, orange peel, and baby sage oleoresins extracted using supercritical CO2 and subsequently emulsified. The oleoresins were incorporated into dark chocolate, and their impact on physicochemical properties was evaluated. Characterization revealed rich sources of phenolic compounds, carotenoids, and volatile compounds in these oleoresins. In vitro studies demonstrated anti-obesogenic, antioxidant, anti-inflammatory, and neuroprotective properties of the emulsified oleoresins. However, only physicochemical properties were determined for the formulations of dark chocolate with these emulsified oleoresins. Chocolate formulations fortified with these emulsions displayed a softer texture, lower water activity, and solid-like behavior. The findings suggest that these oleoresins could serve as nutraceutical agents for mitigating metabolic syndrome and associated pathologies. Incorporating them into chocolate matrices offers a practical approach to formulating functional foods. Further research is warranted to explore the preventive and therapeutic efficacy in an in vivo model.

Supercritical CO2 extraction of naringenin from Mexican oregano (Lippia graveolens): its antioxidant capacity under simulated gastrointestinal digestion

A supercritical CO2 method was optimized to recover naringenin-rich extract from Mexican oregano (Lippia graveolens), a flavanone with high antioxidant and anti-inflammatory activity. The effect of the extraction parameters like pressure, temperature, and co-solvent on naringenin concentration was evaluated. We used response surface methodology to optimize the naringenin extraction from oregano; the chemical composition by UPLC-MS of the optimized extract and the effect of simulated gastrointestinal digestion on its antioxidant capacity and total phenolic content were also evaluated. The optimum conditions were 58.4 °C and 12.46% co-solvent (ethanol), with a pressure of 166 bar, obtaining a naringenin content of 46.59 mg/g extract. Also, supercritical optimized extracts yielded high quantities of cirsimaritin, quercetin, phloridzin, apigenin, and luteolin. The results indicated that the naringenin-rich extract obtained at optimized conditions had higher total phenolic content, antioxidant capacity by TEAC and ORAC, and flavonoid content, compared with the methanolic extract, and the simulated gastrointestinal digestion reduced all these values.

Tetrabutylammonium bromide-based hydrophobic deep eutectic solvent for the extraction and separation of dihydromyricetin from vine tea and its inhibitory efficiency against xanthine oxidase

In this study, deep eutectic solvent oscillation-assisted extraction (DES-OS) combined with macroporous resin adsorption and desorption technology was used to achieve the rapid green extraction and separation of the characteristic component dihydromyricetin (DMY) from vine tea. Multivariate data analysis showed that the DES system composed of tetrabutylammonium bromide (N₄₄₄Br) and pyruvic acid (molar ratio 1 : 2) had good extraction performance for DMY. The influence parameters of DES-OS were studied, and optimized by the single-factor test and response surface methodology (RSM) with Box–Behnken design (BBD). The extraction model of DMY was established and verified. The results showed that the extraction yield of DMY could reach 40.1 mg g⁻¹ under the optimal conditions (DES water contents of 71.18%, extraction time of 2.80 h, extraction temperature of 46.40 °C), which is in good agreement with the predicted value. In addition, Fourier transform infrared spectroscopy (FT-IR) was used to characterize the solvent before and after extraction. Scanning electron microscopy (SEM) results further confirmed that tetrabutylammonium bromide:pyruvate enhanced the destruction of the cell wall structure, resulting in the release of more DMY. Furthermore, different macroporous resins were selected for the separation of DMY for the DES-OS extract, and it was found that the DM301 resin had the ideal recovery performance under optimized dynamic condition. Finally, the product was found to have an inhibitory effect against xanthine oxidase (XO) as a mixed-type competitive inhibitor with IC50 values of (5.79 ± 0.22) × 10⁻⁵ mol L⁻¹. The inhibitory mechanisms of DMY on XO were explored by enzyme kinetics, spectroscopy, molecular docking and molecular dynamics analysis approaches, which provided a theoretical basis for the above inhibition assays.

In this study, deep eutectic solvent oscillation-assisted extraction (DES-OS) combined with macroporous resin adsorption and desorption technology was used to achieve the rapid green extraction and separation of dihydromyricetin (DMY) from vine tea.

Influence of the extraction method on the recovery of bioactive phenolic compounds from food industry by-products

Agro-foodindustries generate colossal amounts of non-edible waste and by-products, easily accessible as raw materials for up-cycling active phytochemicals. Phenolic compounds are particularly relevant in this field given their abundance in plant residues and the market interest of their functionalities (e.g. natural antioxidant activity) as part of nutraceutical, cosmetological and biomedical formulations. In "bench-to-bedside" achievements, sample extraction is essential because valorization benefits from matrix desorption and solubilization of targeted phytocompounds. Specifically, the composition and polarity of the extractant, the optimal sample particle size and sample:solvent ratio, as well as pH, pressure and temperature are strategic for the release and stability of mobilized species. On the other hand, current green chemistry environmental rules require extraction approaches that eliminate polluting consumables and reduce energy needs. Thus, the following pages provide an update on advanced technologies for the sustainable and efficient recovery of phenolics from plant matrices.

Green Extraction of Bioactive Compounds from Plant Biomass and Their Application in Meat as Natural Antioxidant

Plant extracts are rich in various bioactive compounds exerting antioxidants effects, such as phenolics, catechins, flavonoids, quercetin, anthocyanin, tocopherol, rutin, chlorogenic acid, lycopene, caffeic acid, ferulic acid, p-coumaric acid, vitamin C, protocatechuic acid, vitamin E, carotenoids, β-carotene, myricetin, kaempferol, carnosine, zeaxanthin, sesamol, rosmarinic acid, carnosic acid, and carnosol. The extraction processing protocols such as solvent, time, temperature, and plant powder should be optimized to obtain the optimum yield with the maximum concentration of active ingredients. The application of novel green extraction technologies has improved extraction yields with a high concentration of active compounds, heat-labile compounds at a lower environmental cost, in a short duration, and with efficient utilization of the solvent. The application of various combinations of extraction technologies has proved to exert a synergistic effect or to act as an adjunct. There is a need for proper identification, segregation, and purification of the active ingredients in plant extracts for their efficient utilization in the meat industry, as natural antioxidants. The present review has critically analyzed the conventional and green extraction technologies in extracting bioactive compounds from plant biomass and their utilization in meat as natural antioxidants.

Growth Suppression of a Gingivitis and Skin Pathogen Cutibacterium (Propionibacterium) acnes by Medicinal Plant Extracts

Propionibacterium acnes, newly reclassified as Cutibacterium acnes, is an anaerobic Gram-positive bacterium causing acne, found mainly on the skin. In addition, P. acnes is responsible for inflammation of the gums (gingivitis) and blood vessels, consequently leading to various diseases in the human body. In recent years, the evolution of microorganisms, such as P. acnes, that have become resistant to many commercial antibiotics due to the widespread use of antimicrobial drugs in the treatment of infectious diseases has emerged as a major clinical problem. We here analyzed the potential use of 37 medicinal plant extracts as plausible candidates for treating P. acnes, in terms of total phenolic and flavonoid contents, antioxidants scavenging and antimicrobial activity. Consequently, methanol extracts from 14 medicinal plants showed promising antimicrobial activities against P. acnes. In particular, as the extracts from Chrysosplenium flagelliferum F. and Thuja orientalis L. exhibited distinct antimicrobial activities in both the broth dilution and disc diffusion assay, they could be effectively used as active ingredients for preventing or treating inflammatory periodontal diseases, such as periodontitis.

Supercritical Fluid-Based Decellularization Technologies for Regenerative Medicine Applications

Supercritical fluid-based extraction technologies are currently being increasingly utilized in high purity extract products for food industries. In recent years, supercritical fluid-based extraction technology is transformed in biomaterials process fields to be further utilized for tissue engineering and other biomedical applications. In particular, supercritical fluid-based decellularization protocols have great advantage over the conventional decellularization as it may allow preservation of extracellular matrix components and structures. In this review, the latest technological development utilizing the supercritical fluid-based decellularization for regenerative medicine is introduced.

Syrup from Common Date Variety (Phoenix dactylifera L.): Optimization of Sugars Extraction and their Quantification by High Performance Liquid Chromatography

Background:

In Algeria, important quantities of secondary date variety (Phoenix dactylifera L.) are generated in each campaign; their chemical composition is similar to that of commercial dates. The present work aims to valorize this common date variety (Degla-beida) which is often poorly exploited.

Methods:

In this context, we tried to prepare syrup from the secondary date variety and evaluate the effect of conventional extraction (CE) or water bath extraction (WBE) and alternative extraction (microwaves assisted extraction (MAE) and ultrasound-assisted extraction (UAE)) on its total sugar content (TSC), using response surface methodology (RSM). Then, the analysis of individual sugars was performed by high performance liquid chromatography (HPLC).

Results:

Maximum predicted TSC recoveries under the optimized conditions for MAE, UAE and CE were 233.248 ± 3.594 g/l, 202.889 ± 5.797 g/l and 233.535 ± 5.412 g/l, respectively, which were close to the experimental values: 233.796 ± 1.898 g/l; 202.037 ± 3.401 g/l and 234.380 ± 2.425 g/l. HPLC analysis revealed high similarity in the sugar composition of date juices obtained by MAE (60.11% sucrose, 16.64% glucose and 23.25% fructose) and CE (50.78% sucrose, 20.67% glucose and 28.55% fructose), although a large difference was detected for that obtained by UAE (0.00% sucrose, 46.94% glucose and 53.06% fructose).

Conclusion:

Microwave-assisted extraction was the best method for the preparation of date syrup with an optimal recovery of total sugar content. However, ultrasound-assisted extraction was the best one for the preparation of date syrup with high content of reducing sugars.

Effects of Thermal Treatment on the Physical Properties of Edible Calcium Alginate Gel Beads: Response Surface Methodological Approach

Calcium alginate gel (CAG) has been widely investigated for the development of artificial foods; however, there are few studies on its thermal stability. This study aimed to monitor changes in the physical properties of CAG beads during heat treatment using response surface methodology. Heating temperature (X₁, 40–100 °C) and heating time (X₂, 5–60 min) were chosen as independent variables. The dependent variables were rupture strength (Y₁, kPa), size (Y₂, μm), and sphericity (Y₃, %). The heating temperature (X₁) was the independent variable that had a significant effect on the rupture strength (Y₁) and size (Y₂). Rupture strength (Y₁) increased as the heating temperature (X₁) increased; at the same time, the CAG beads size (Y₂) decreased. With all conditions, the values of sphericity (Y₃) were over 94%. SEM images revealed that increase in the rupture strength of the CAG beads by heat treatment resulted from their porous structures. Loss of moisture by syneresis, occurring with heat treatment, was judged to create a dense porous structure of CAG beads. Our findings offer useful information for cooking or sterilizing food products utilizing CAG beads. In addition, thermal treatment could be applied to produce hard CAG beads with a high rupture strength.

Modified Supercritical Carbon Dioxide Extraction of Biologically Active Compounds from Feijoa Sellowiana Leaves

For the first time, the modified supercritical carbon dioxide extraction (MSCE) of biologically active compounds from Feijoa sellowiana leaves was investigated. Total yield (TY) and bioactivity of biocompounds in terms of DPPH• (%DPPHsc) and HO• (%HOsc) radicals scavenging were maximized via multivariate optimization. The optimized conditions were the pressure of 272.34 bar, supercritical carbon dioxide flow rate of 1.58 mL min−1, temperature of 52.48 °C, and dynamic extraction time of 110.62 min. The predicted values of the TY, %DPPHsc, and %HOsc were 81.12 mg g−1, 85.16 %, and 75.66 %, respectively. The chromatographic analysis demonstrated gallic acid as the main biophenolic (136.20 ± 0.16 mg g−1). The scanning electron microscopy images showed dramatic disruption of cells treated with MSCE. A comprehensive comparison was made between current findings and other techniques (conventional and ultrasonic waves assisted extraction). More TY was achieved using conventional method but the bioactivity of MSCE products was considerably better.

Effect of emergent non-thermal extraction technologies on bioactive individual compounds profile from different plant materials

Extraction is the first step for isolation and purification of interesting bioactive compounds, by mixing of the plant material with an adequate solvent. Those bioactive compounds are, usually, secondary metabolites, such as phenolic acids and flavonoids which are present in closed insoluble structures, making its extraction a challenge. There are many different traditional extraction methods, such as Soxhlet, heat reflux, and maceration. Nevertheless, due to several disadvantages, they are being replaced by new methods, using emergent technologies, such as high hydrostatic pressure, ultrasounds, pulsed electric fields, and supercritical fluids. The use of novel technologies allows enhancing mass transfer rates, increasing cell permeability as well as increasing secondary metabolite diffusion, leading to higher extraction yields, fewer impurities on the final extract, extractions at room temperature with thermo-sensitive structures preservation, use of different non-organic solvents, low energy consumption, short operation time, and have no significant or lower effect on the structure of bioactive compounds. This paper aims to review the effect of the main emergent extraction technologies (high hydrostatic pressure, pulsed electric fields, ultrasounds, and supercritical fluid assisted) on the individual profile of bioactive compounds from plant material.

Mentha spicata L. infusions as sources of antioxidant phenolic compounds: emerging reserve lots with special harvest requirements

Mentha spicata L., commonly known as spearmint, is widely used in both fresh and dry forms, for infusion preparation or in European and Indian cuisines. Recently, with the evolution of the tea market, several novel products with added value are emerging, and the standard lots have evolved to reserve lots, with special harvest requirements that confer them with enhanced organoleptic and sensorial characteristics. The apical leaves of these batches are collected in specific conditions having, then, a different chemical profile. In the present study, standard and reserve lots of M. spicata were assessed in terms of the antioxidants present in infusions prepared from the different lots. The reserve lots presented the highest concentration in all the compounds identified in relation to the standard lots, with 326 and 188 μg mL^-1 of total phenolic compounds, respectively. Both types of samples presented rosmarinic acid as the most abundant phenolic compound, at concentrations of 169 and 101 μg mL^-1 for reserve and standard lots, respectively. The antioxidant activity was higher in the reserve lots which had the highest total phenolic compounds content, with EC₅₀ values ranging from 152 to 336 μg mL^-1. The obtained results provide scientific information that may allow the consumer to make a conscientious choice.

Effects of processing parameters on the caffeine extraction yield during decaffeination of black tea using pilot-scale supercritical carbon dioxide extraction technique

In this pilot-scale study supercritical carbon dioxide (SCCO₂) extraction technique was used for decaffeination of black tea. Pressure (250, 375, 500 bar), extraction time (60, 180, 300 min), temperature (55, 62.5, 70 °C), CO₂ flow rate (1, 2, 3 L/min) and modifier quantity (0, 2.5, 5 mol%) were selected as extraction parameters. Three-level and five-factor response surface methodology experimental design with a Box-Behnken type was employed to generate 46 different processing conditions. 100% of caffeine from black tea was removed under two different extraction conditions; one of which was consist of 375 bar pressure, 62.5 °C temperature, 300 min extraction time, 2 L/min CO₂ flow rate and 5 mol% modifier concentration and the other was composed of same temperature, pressure and extraction time conditions with 3 L/min CO₂ flow rate and 2.5 mol% modifier concentration. Results showed that extraction time, pressure, CO₂ flow rate and modifier quantity had great impact on decaffeination yield.

Solvent Supercritical Fluid Technologies to Extract Bioactive Compounds from Natural Sources: A Review

Supercritical fluid technologies offer a propitious method for drug discovery from natural sources. Such methods require relatively short processing times, produce extracts with little or no organic co-solvent, and are able to extract bioactive molecules whilst minimising degradation. Supercritical fluid extraction (SFE) provides a range of benefits, as well as offering routes to overcome some of the limitations that exist with the conventional methods of extraction. Unfortunately, SFE-based methods are not without their own shortcomings; two major ones being: (1) the high establishment cost; and (2) the selective solvent nature of CO₂, i.e., that CO₂ only dissolves small non-polar molecules, although this can be viewed as a positive outcome provided bioactive molecules are extracted during solvent-based SFE. This review provides an update of SFE methods for natural products and outlines the main operating parameters for extract recovery. Selected processing considerations are presented regarding supercritical fluids and the development and application of ultrasonic-assisted SFE methods, as well as providing some of the key aspects of SFE scalability.

Simultaneous determination of 19 fatty acids in Antrodia camphorata by derivatized GC-MS and evaluation of antioxidant activity of Antrodia camphorata crude oil

To analyze the components of the fatty oil extracted from Antrodia camphorata fungus powder and to evaluate the antioxidant activity of A. camphorata crude oil. A derivatized gas chromatography mass spectrometry (GC-MS) was developed for the quantification of 19 fatty acids in extracts of A. camphorata obtained by supercritical carbon dioxide (SC-CO2). Good separation was obtained under the optimized chromatographic conditions and 19 target compounds after methyl-esterification were identified by GC-MS on a HP-VOC capillary column (60 m × 320 μm × 1.8 μm) with an initial temperature set at 80 °C. The validity of the established method was examined experimentally with good linearity, intra-assay precisions, repeatability, stability and recovery. The antioxidant activity of A. camphorata crude oil was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assay. Nineteen fatty acids showed good linearity over the tested ranges (r > 0.9956) and the recovery ranged from 93.47 to 104.89 %. The crude oil extracted from A. camphorata fungus powder also revealed its antioxidant activity. It was the report about simultaneous determination of 19 fatty acids in A. camphorata and antioxidant activity of its crude oil for the first time. The established method might also be utilized for the investigation of edible plant materials and agricultural products containing fatty acids.