The 42nd Symposium Chromatographic Methods of Investigating Organic Compounds : Book of abstracts

The 42nd Symposium Chromatographic Methods of Investigating Organic Compounds : Book of abstracts. June 4-7, 2019, Szczyrk, Polan

Optimization of Antifungal Properties of Hop Cone Carbon Dioxide Extracts Based on Response Surface Methodology

Response surface methodology (RSM) was employed to optimize the process parameters of the supercritical carbon dioxide extraction of hop cones in terms of their antifungal properties against Fusarium culmorum and Aspergillus niger. The effects of temperature (40–50 °C), pressure (200–300 bar), and CO2 consumption (25–75 kgCO2/kg) on the extraction yield, content of α- and β-acids, as well as pathogens’ growth inhibition were investigated. Both pressure and CO2 consumption had a significant effect on antifungal properties. It was observed that the best results for antifungal properties were obtained when hop cones were extracted with pure carbon dioxide at the temperature of 50 °C, under the pressure of 300 bar with CO2 consumption at the level of 75 kgCO2/kg of feed for extraction. The highest antifungal properties of hop cone supercritical carbon dioxide extracts were analyzed as 100% for Fusarium culmorum and 68% for Aspergillus niger, calculated as the growth inhibition of tested pathogens. The aim of the study was to determine the optimum values of extraction parameters to achieve the maximum response and enable us to investigate the interaction of these parameters on the antifungal properties of hop cone extracts

The Application of Supercritical Fluid Extraction in Phenolic Compounds Isolation from Natural Plant Materials

The separation of phenolic compounds by supercritical fluid extraction has been widely studied throughout the last two decades. This is evidenced by a number of publications and articles. Supercritical fluid extraction (SFE) has become thus the effective method of separating the mentioned group of compounds. On the other hand, SFE is a beneficial approach in plant waste materials utilization and reduction of environmental burdens caused by the wastes. The aim of the study is to gather and systematize available information on the phenolic compounds separation that have been reported so far as well as to evaluate whether there is one optimal supercritical fluid extraction method for the phenolic compounds

Influence of supercritical carbon dioxide extraction process temperature and co-solvent addition on the quality of green tea leaves extracts

Interest in the separation of green tea extracts continues to grow due to its significant bioactivity, wide applicability as well as a large number of green tea spices, variety of extraction techniques, and lack of systematic data. The present early stage work was intended to estimate the effect of temperature and co-solvent addition on an amount of separated constituents from green tea (gunpowder tea variety, China) during the supercritical carbon dioxide (sc-CO2) extraction process. For this purpose, the temperature of the supercritical extraction process was increased up to 90 °C at a constant pressure of 30 MPa. After the selection of appropriate conditions, co-solvents (ethanol, ethanol/water, and water) were added to sc-CO2. Obtained extracts were analyzed regarding total phenolic content (TPC), total flavonoid content (TFC), DPPH radical scavenging activity, total chlorophyll, and total carotenoid content. The results of the supercritical extraction process were compared with the conventional extraction process (extraction using Soxhlet apparatus). The results showed that a linear decrease in the density of neat sc-CO2 led to a linear increase in extraction yields up to 5.5%. The addition of co-solvents had a variable effect on the amount of separated extracts. While it increased extraction yields at a lower temperature, it decreased extraction yields at a higher temperature. An increase in temperature for the extraction process with neat sc- CO2 also decreased TPC, TFC, chlorophylls, and carotenoids content. The addition of co-solvents to sc-CO2 increased amounts of tested compounds in obtained extracts. It was interesting to notice a decrease in the amount of tested compounds with an increase in water content during extractions. The highest values of TPC and TFC detected were 136.5 mg GAE/g and 40.7 mg QE/g, respectively. Extract solutions with a concentration of 20 mg/mL inhibited up to 65% of DPPH radical. Chlorophyll A, chlorophyll B, and carotenoids were detected in amounts up to 8.1 g/kg, 0.7 g/kg, and 0.5 g/kg of dry extract, respectively. Extracts obtained by conventional extraction contained higher amounts of TPC and TFC. On the other hand, those extracts contained lower amounts of total chlorophylls and carotenoids. Although supercritical extraction processes from green tea leaves have been performed for decades and its industrial application is present, there are still many unknowns. To the best of our knowledge, this is the first report in available literature on chlorophyll and carotenoid contents in supercritical extracts from green tea. Also tested process parameters enabled the achievement of higher yields (for neat sc-CO2) as well as higher TPC compared with previously reported ones for green tea supercritical extracts. Chemical analysis of obtained extracts is pending

Supercritical Carbon Dioxide (scCO2) Extraction of Phenolic Compounds from Lavender (Lavandula angustifolia) Flowers: A Box-Behnken Experimental Optimization

Due to their numerous health benefits associated with various diseases and anti-oxidation properties, the phenolic compounds collectively referred to as phytochemicals have attracted a lot of interest, however, a single extraction method for polyphenols has not been developed yet. Supercritical fluid extraction, a green extraction method, provides the final product without organic solvent residues. In this work the extraction of lavender was performed using supercritical carbon dioxide. A statistical experimental design based on the Box-Behnken (B-B) method was planned, and the extraction yields and total phenolic contents were measured for three different variables: pressure, temperature and extraction time. The ranges were 200–300 bar, 40–60 °C and 15–45 min. The extracts yields from scCO2 extraction were in the range of 4.3–9.2 wt.%. The highest yield (9.2 wt.%) was achieved at a temperature of 60 °C under the pressure of 250 bar after 45 min. It also corresponded to the highest total phenolic content (10.17 mg GAE/g extract). Based on the study, the statistically generated optimal extraction conditions to obtain the highest total phenolic compounds concentration from flowers of Lavandula angustifolia were a temperature of 54.5 °C, pressure of 297.9 bar, and the time of 45 min. Based on the scavenging activity percentage (AA%) of scCO2 extracts, it is concluded that the increase of extraction pressure had a positive influence on the increase of AA% values

Supercritical fluid extraction from native and defatted milk thistle, dandelion, and chamomile seeds

The supercritical fluid extraction (SFE) technique that employs supercritical carbon dioxide (SC-CO2) has been reported to be superior (compared to mechanical and extractions with organic solvents) for the separation of oils from seeds [1]. Current work aims to show that besides oils, additional valuable extracts can be recovered from defatted seeds. For that purpose, seeds of milk thistle, dandelion and chamomile grown in Poland have been tested. Initially, SFE for oil separation from seeds was tested by variation in pressure (from 100 to 450 bar) and temperature (from 40 to 80 °C) [2–4]. The yield and composition of oils indicated optimal conditions for the separation of extracts from defatted seeds using SC-CO2 with ethanol. ..

Antifungal Properties of Fucus vesiculosus L. Supercritical Fluid Extract Against Fusarium culmorum and Fusarium oxysporum

In this study, potential antifungal properties of a brown alga Fucus vesiculosus were evaluated. The algal extract was obtained with the use of supercritical fluid extraction (scCO2) at a temperature of 50 °C under a pressure of 300 bar. The aqueous solution of the extract at the concentration of 0.05%, 0.2%, 0.5% and 1.0% was studied against pathogenic fungi on a liquid RB medium. This study is the first report on antifungal properties of the brown algae F. vesiculosus scCO2 extract against Fusarium culmorum and Fusarium oxysporum phytopathogens. The concentrations of the studied extract (0.5% and 1.0%) were demonstrated to have an ability to inhibit 100% growth of macroconidia within 144 h, as well as an ability to cause their total degradation. As a result of the study, the antifungal effect of fucosterol against F. culmorum was also indicated. The total macroconidia growth was inhibited by 1.0% fucosterol. Moreover, at lower concentrations (0.05–0.2%) of fucosterol, macroconidia were characterized by shorter length and structural degradation was observed. The mycelial growth of Fusarium oxysporum (Fo38) by 1% scCO2 F. vesiculosus extract was analyzed at the level of 48% after 168 h of incubation, whereas 100% extract was found to be effective in F. culmorum (CBS122) and F. oxysporum (Fo38) growth inhibition by 72% and 75%, respectively after 168 h of incubation

SUPERCRITICAL CO2 EXTRACTION FROM DANDELION: THE EFFECT OF PRESSURE ON EXTRACTS YIELD AND COMPOSITION

Dandelion (Taraxacum officinale) is becoming an industry valuable crop due to the increase in its utilization in the food and phytopharmaceutical industry. Nonetheless, its application is still limited especially considering its extracts. Therefore, this study was aimed at exploring dandelion seeds as a source of bioactive compounds. For this purpose, an environmentally friendly supercritical CO2 extraction technique was employed and extracts were separated at pressures of 10-45 MPa and a temperature of 313 K. Obtained extracts were characterized using a gas chromatograph equipped with mass spectroscopy (GC-MS), a gas chromatograph equipped with flame ionization detector (CGFID), as well as by Folin–Ciocalteu and DPPH assays using a UV/VIS spectrophotometer. It was shown that the selection of process pressure determined both extract yield and extract composition. An increase in pressure increased extraction yield from 7.4 to 25.2% and the content of dominant linoleic and oleic fatty acids (from 536.3 to 658.3 mg/g and 125.8 to 161.7 mg/g, respectively). Total phenolic and flavonoid content in obtained extracts ranged from 5.5 to 9.0 mg GAE/g and from 208.6 to 497.5 mg QE/g, respectively. The strongest DPPH radical scavenging activity with inhibition of 64.4% was recorded for extract obtained at 10 MPa for extract solution concentration of 20 mg/mL. Obtained results confirmed that extracts obtained from dandelion seeds are a valuable source of bioactive compounds

An Eco-Friendly Supercritical CO₂ Recovery of Value-Added Extracts from <i>Olea europaea</i> Leaves

An eco-friendly approach towards the recovery of value-added extracts from olive tree leaves with the aid of supercritical CO2 at 30 MPa was carried out. The impact of extraction temperature (35–90 °C) and presence of co-solvents (ethanol, water, and aqueous ethanol) on the total phenolic, flavonoid, and pigment content, as well as oleuropein, hydroxytyrosol, tyrosol, and α-tocopherol content was determined. In addition, the antioxidant activity of extracts from tree leaves using DPPH, ABTS, and CUPRAC assays was investigated. The results of the study showed that the most effective supercritical CO2 extraction was at 90 °C with an addition of ethanol, which enabled the separation of extract with the highest content of tested compounds. Some of the highest recorded values were for oleuropein 1.9 mg/g, for carotenoids 5.3 mg/g, and for α-tocopherol 2.0 mg/g. Our results are expected to contribute to the efforts towards the valorization of olive leaves as a sustainable source of valuable compounds, and boost local economies as well as the interest of pharmaceutical, food, and cosmetic industries for novel food by-product applications

The Influence of Subcritical Water Extraction Parameters on the Chemical Composition and Antioxidant Activity of Walnut (<i>Juglans regia</i> L.) Bark Extracts

This study investigated the impact of subcritical water extraction parameters on the polyphenols and flavonoids content in extracts made of the bark of walnut (Juglans regia L.), as well as antioxidant activity measured using the DPPH and FRAP methods. The total polyphenols (TPC) and flavonoid (TFC) were determined using the spectrophotometric (UV-Vis) method. The response surface methodology (RSM) was employed to optimize the yield of bioactive compounds. On the basis of developed model, the highest polyphenols (192.2 mg (GAE)/100 g (dry mass)) (GAE—gallic acid equivalent), flavonoids (88.3 mg(QE)/100 g (dry mass)) (QE—quercetin equivalent) contents and antioxidant activity (21.3 × 10−6 MTE/1 g (dry mass)) (TE-Trolox equivalent) were obtained under the following extraction conditions: temperature 131.6 °C, raw material fraction size 0.9 mm and process time 10 min. The greatest impact on the extraction yield was observed in the case of the temperature, whereas the raw material fraction size and the process time had a secondary impact. Obtained results indicate that a smaller particle size and a shorter time may improve the process; however, a reduction in particle size can be challenging for a pressure cell filtration system and consequently increase the cost of the raw material pretreatment process. With the reduction in the process time, a lower cost of extract production can be achieved. This study confirmed the importance of a proper selection of extraction parameters to obtain the demanded extract composition