Total Polyphenol Content Research Articles

Comprehensive evaluation of quality and bioactivity of kombucha from six major tea types in China

Kombucha is a kind of fermented tea prepared with a symbiotic culture of bacteria and yeasts (SCOBY) on the basis of sugared black tea infusion. In the current study, six major Chinese tea leaves (dark tea, black tea, oolong tea, white tea, yellow tea, and green tea) were used to prepare kombucha and their physiochemical properties, bioactivity, and sensory quality were compared. The total acidity of kombucha increased as the fermentation proceeded, decreasing the pH value from ∼6.0 to ∼2.5. Moreover, the antioxidant capacity was significantly increased after fermentation compared to fresh tea infusions and this is mostly attributed to the increased total polyphenols concentration (from 1333.25 mg/L to 1683.24 mg/L). Antimicrobial experiments showed fermentation enhanced the antimicrobial effects of kombucha, and oolong tea kombucha showed the strongest bacteriostatic capacity against Staphylococcus aureus (S. aureus) while the yellow tea kombucha showed the strongest bacteriostatic capacity against Escherichia coli (E. coli). Volatile components and sensory evaluation results revealed that the tea types remarkably influenced the flavors of kombucha. Generally, oolong tea kombucha and green tea kombucha had higher overall sensory scores than other samples. In conclusion, the types of tea significantly influenced the quality of kombucha, and fermentation favors the improvement in the anti-oxidant and antimicrobial properties of kombucha.

Effect of temperature, pressure, sugar, and citric acid content on quality of cashew apple juice produced by vacuum concentration

Cashew apples are a source of by-products in the cashew industry. In the present work, a juice product made from cashew apples was produced through vacuum concentration (VC). During VC, a temperature range of 60 to 90°C, and a pressure range of 500 to 650 mmHg were investigated. Total ascorbic acid (TAA), total tannin content (TTC), and total polyphenol content (TPC) after VC were also evaluated. The variation in VC time was observed when the temperature was investigated. The sensory value of the products after mixing citric acid and sugar was evaluated. The results showed that the nutritional parameters were affected by temperature and pressure. TAA and TPC reached their maximum value at 80°C. The TTC was strongly hydrolysed with increasing VC temperature. Furthermore, negative correlation between vacuum pressure and nutrition was observed. Cashew apple juice after VC diluted with water (1:5), and mixed with sugar (20 g/L) and citric acid (0.2 g/L) was preferred by consumers. TAA, TPC, and TTC were monitored for 42-day storage under two temperature conditions of 35 and 45°C. The shelf life of the product reached 117 d. These results set the platform for the development of beverage products from cashew apple by-products, thereby improving the economy of the cashew industry in Vietnam and the world.

Functional components and antioxidant activity were improved in ginger fermented by Bifidobacterium adolescentis and Monascus purpureus

Microbial fermentation, a widely used food processing technology, enhanced the biological activity and nutritional profile of raw materials. The impact of fermentation by Bifidobacterium adolescentis and Monascus purpureus on the functional components and antioxidant activity of ginger was investigated. The results showed that ginger fermented by the two strains notably increased the content of gingerol, total flavonoids, and total polyphenols, and enhanced its antioxidant capacity as measured by various assays such as DPPH, ABTS, and FRAP. The active components and antioxidant capacity were superior in ginger fermented by M. purpureus compared to B. adolescentis. The comparison of organic acid components demonstrated that the content of lactic acid and succinic acid was increased in ginger fermentation by B. adolescentis, while that of acetic acid, fumaric acid and citric acid was increased in ginger fermentation by M. purpureus. The Pearson correlation analysis showed a positive relation between the content of gingerol, total flavonoids, and total polyphenols, Monascus pigments, Monacolin K, and antioxidant capacity. Therefore, fermentation has the potential to enhance the functional components and antioxidant activity of ginger. This study might have implications for the development of ginger-based products and the theoretical basis for the deep processing of ginger.

Comprehensive evaluation of chemical constituents and antioxidant activity between crude and processed Polygalae radix based on UPLC-Q-TOF-MS/MS combined with multivariate statistical analysis

Polygalae radix (PR) is a famous herbal medicine obtained by drying the root of Polygala tenuifolia Willd., one of the traditional Chinese medicines (TCM) that can be used for healthy food. There are three main processed methods of PR, including removing the xylem of roots (Polygalae Cortex, PC), frying PC with licorice (LP), and frying PC with honey (HP). While processing is believed to enhance efficacy and reduce toxicity, it is crucial to understand the differences in chemical composition and biological activities between crude and processed PR. This study used ultra-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) combined with multivariate statistical analysis to analyze the chemical profiles and differences between the crude and processed products. Total polyphenol contents (TPC), total flavonoid contents (TFC), total saponin contents (TSC) and antioxidant activity of the processed and crude PR were also investigated. A total of 131 chemical compounds, including 42 saponins, 44 oligosaccharide esters, 25 xanthones, 2 organic acids, 3 Carbohydrates, and 15 components detected in auxiliary materials, were detected in all samples. Notably, PC exhibited significant changes among the three processed products, with the content of 62 compounds being higher. Processing of licorice (LP) and honey (HP) decreased the content of several compounds due to temperature and moisture influences. Comprehensive comparison of the antioxidant capacity of crude and processed PR showed that the antioxidant capacity of PC was higher than that of PR, HP, and LP. Our results can provide a scientific basis for further developing and applying P. tenuifolia resources.

Exploring the Antioxidant Properties of Citrus limon (Lemon) Peel Ultrasound Extract after the Cloud Point Extraction Method

Each year, a substantial amount of food is discarded around the globe. A significant portion of this waste consists of by-products derived from Citrus fruits such as lemons. The purpose of this research is to examine the polyphenol extraction and the antioxidant ability of lemon peel using cloud point extraction (CPE), a sustainable approach. CPE was conducted using three steps with a 20% w/v concentration of Span 20 as the surfactant, which has a critical micellar concentration of 6.13 × 10−5 mol/L. The pH was set at 7 and a salt concentration of 20% was maintained at 45 °C for 20 min. The subsequent outcomes of the analysis were obtained: total polyphenol content (TPC): 526.32 mg gallic acid equivalents per liter; total flavonoid content (TFC): 90.22 mg rutin equivalents per liter; FRAP, DPPH, and hydrogen peroxide assays: 2.40, 2.68 and 1.03 mmol ascorbic acid equivalents per liter, respectively, and 168.63 mg/L ascorbic acid content. The quantification of the polyphenolic compounds through High-Performance Liquid Chromatography showed that the most abundant compounds in the lemon peels are eriocitrin (159.43 mg/L) and hesperidin (135.21 mg/L). The results indicate that the proposed CPE technique is successful in extracting antioxidant compounds from lemon peels. The generated extracts have the potential to be exploited as dietary additives to enhance human health and can also be utilized for nutraceuticals or pharmaceutical purposes.

Optimizing Extract Preparation from Laurel (Laurus nobilis L.) Leaves Using a Pulsed Electric Field

This study explores the bioactive compound extraction from laurel (Laurus nobilis L.) leaves using a pulsed electric field (PEF) as a standalone extraction technique. The primary parameters impacting the extraction process were optimized through response surface methodology. Specifically, solvent composition (ethanol and water mixtures) and liquid-to-solid ratio, along with other key PEF conditions (i.e., electric field intensity, pulse period, and pulse length) were examined. The antioxidant capacity was evaluated through DPPH and FRAP assays, whereas total polyphenol content was also measured. A comparison was also made between the extracts produced with and without PEF. The results showed that after 30 min of extraction, the best parameters were a pulse period of 355 μs, a pulse duration of 55 μs, and an electric field intensity of 0.6 kV/cm. A liquid-to-solid ratio of 10 mL/g was chosen, whereas the best solvent was determined to be 25% (v/v) ethanol/water mixture. The PEF-treated extract contained 77% more polyphenols compared to the untreated sample. In addition, PEF-treated samples had a rise of up to 288% for certain individual polyphenols. Correlation analyses also revealed interesting trends among bioactive compounds and the antioxidant capacity of the extracts. The effect of the investigated parameters on polyphenol recovery was demonstrated, indicating that comparable investigations should consider these parameters to optimize polyphenol extraction yield. Regarding green and non-thermal standalone techniques, PEF outshines other extraction techniques as it could also be used as a sustainable way to swiftly generate health-promoting extracts from medicinal plants.

Supercritical Fluid Extraction of Bioactive Components from Apple Peels and Their Modulation of Complex I Activity in Isolated Mitochondria.

Supercritical fluid extraction (SFE) was used to extract bioactive compounds from apple (Malus domestica) peel waste from three different Italian cultivars. The bioactive fractions were extracted applying a temperature of 60 °C and a pressure of 250 bar for 15 min with 20% ethanol as co-solvent, at a flow rate of 2 mL/min. The total polyphenol (TP), anthocyanin (TA), ascorbic acid (AA), and antioxidant activity contents (TACs) were measured, while chromatographic analyses were performed to highlight the differences between the extracts. The Stark cultivar had the highest levels of polyphenols, anthocyanins, and ascorbic acid, while the Royal Gala cultivar showed the highest total antioxidant activity. SFE extracts were then tested for their effect on the mitochondrial NADH-ubiquinone oxidoreductase (Complex I) activity on mitochondria isolated from human embryonic kidney cells (HEK239). The Stark extract showed the most positive response in terms of NADH oxidation. The results obtained in this work highlight the potential of apple peel waste as a source of functional phytocompounds and suggest that Stark cultivar extracts may be exploited for pharmacological applications. This study supports the circular bioeconomy by promoting the use of waste products as a valuable resource.

Spectrophotometric and Chromatographic Assessment of Total Polyphenol and Flavonoid Content in Rhododendron tomentosum Extracts and Their Antioxidant and Antimicrobial Activity.

In the literature, the chemical composition of Rhododendron tomentosum is mainly represented by the study of isoprenoid compounds of essential oil. In contrast, the study of the content of flavonoids will contribute to the expansion of pharmacological action and the use of the medicinal plant for medical purposes. The paper deals with the technology of extracts from Rh. tomentosum shoots using ethanol of various concentrations and purified water as an extractant. Extracts from Rh. tomentosum were obtained by a modified method that combined the effects of ultrasound and temperature to maximize the extraction of biologically active substances from the raw material. Using the method of high-performance thin-layer chromatography in a system with solvents ethyl acetate/formic acid/water (15:1:1), the following substances have been separated and identified in all the extracts obtained: rutin, hyperoside, quercetin, and chlorogenic acid. The total polyphenol content (TPC) and total flavonoid content (TFC) were estimated using spectrophotometric methods involving the Folin-Ciocalteu (F-C) reagent and the complexation reaction with aluminum chloride, respectively. A correlation analysis was conducted between antioxidant activity and the polyphenolic substance content. Following the DPPH assay, regression analysis shows that phenolic compounds contribute to about 80% (r2 = 0.8028, p < 0.05) of radical scavenging properties in the extract of Rh. tomentosum. The extract of Rh. tomentosum obtained by ethanol 30% inhibits the growth of test cultures of microorganisms in 1:1 and 1:2 dilutions of the clinical strains #211 Staphylococcus aureus and #222 Enterococcus spp. and the reference strain Pseudomonas aeruginosa ATCC 10145.

Physicochemical Properties of Apple Purees and Peel Extract for Potential Use in Pastry Products

In recent years, the consumption of pastry and bakery products has grown considerably, and consumers are increasingly tempted to choose products from an organoleptic point of view. At the same time, consumers are also interested in having a healthy diet, respectively, products with special sensory properties, but with a low sucrose content. Substituting the sucrose in these products with apple puree represents an alternative to obtaining cakes with a lower sugar content and, in addition, in obtaining products with high nutritional value, with the bioactive compounds from apples having special properties on health. The purpose of this work was to analyze both the physicochemical properties, the total content of polyphenols and the antioxidant activity of the apple puree samples, as well as their variation during the storage period. The physicochemical properties analyzed were: moisture content, titratable acidity, ash content, pH, water activity, total soluble solids content and color. Regarding the content of the bioactive compounds, the total content of polyphenols and the antioxidant capacity were determined by the Folin–Ciocalteu method, respectively, the DPPH method. The results showed that apple puree is an important source of polyphenols, and these are the main factors influencing antioxidant activity. The analysis of the properties of the three products obtained from the apple will allow you to choose one of them or a combination of them in order to obtain the highest degree of sugar substitution and the highest nutritional value of the products. The degree of substitution will be correlated with technological parameters, baking temperature and time.

The Effect of Brewing Time on the Antioxidant Activity of Tea Infusions

Many studies have found that tea has an antioxidant, anti-inflammatory, anti-cancer, anti-obesogenic and anti-diabetic effect, mostly associated with the content of anti-oxidant compounds. Polyphenols, being the main secondary metabolites in tea, are often considered the physiological markers determining a tea’s quality. Apart from the tea production process and tea components, brewing conditions can also influence the levels of antioxidants in tea. This study aimed to verify whether the brewing time of various tea types (5, 10 and 15 min) affects the level of extraction of antioxidant compounds into infusions and their antioxidant activity. We examined 11 types of tea: green leaf tea, green tea bags, white tea bags, black tea bags, red tea bags, black leaf tea, yerba mate, raspberry tea bags, butterfly pea flower (Clitoria ternatea) tea, white lychee plum tea and hibiscus flower tea. Total polyphenol (TPC), flavonoids and anthocyanins content, as well as determination of antiradical and antioxidant capacity with DPPH radical and ABTS radical cation, were determined using spectrophotometric assays. Due to the antioxidant activity of tea infusions, the optimum brewing time for green tea (leaf and bags), black tea (leaf and bags), butterfly pea flower tea, white tea, white lychee plum tea, raspberry tea and yerba mate is 15 min. Red tea brewing time should be ten minutes, and for hibiscus flower tea it should be five minutes. The results refer to the brewing temperature recommended by tea manufacturers.

Quinoa–Olive Agroforestry System Assessment in Semi-Arid Environments: Performance of an Innovative System

Agroforestry is a promising way to sustain land use efficiency in semi-arid areas. In this study, we introduce quinoa as a drought- and salinity-tolerant crop in olive-based agroforestry. We investigated how the microclimate created by olive trees affects agronomic and biochemical traits in quinoa and evaluated the performance of this new olive-based agroforestry system in terms of land equivalent ratio (LER). Field experiments were carried out under two pedoclimatic conditions (S1) and (S2) using a randomized complete block design with two cropping systems (sole crop (SCS) and agroforestry (AFS) systems), four quinoa cultivars (Puno, Titicaca, ICBA-Q5, and ICBA-Q4) and one olive orchard as a control (OR) in each block. Our results show that AFS had lower grain yield (−45%), dry biomass (−49%), and crop water productivity (−44%), but higher plant height (12%), grain protein (4%), saponin (26%), total polyphenol (12%), and DPPH (9%) contents compared to SCS. The highest grain yield was recorded for Titicaca and ICBA-Q5 (1.6 t ha−1). The LER ranged from 1.57 to 2.07, indicating that the overall productivity was 57% to 107% higher in the agroforestry system compared with the monoculture. We suggest that quinoa–olive tree intercropping could be a promising agroecological practice under semi-arid conditions.

Evaluation of the Nutritional Value of Prunus dulcis Blossoms and the Antioxidant Compounds of Their Extracted Oil Using Green Extraction Method

Edible blossoms and extracted oils from various parts of plants have gained the interest of researchers in recent years due to their strong antioxidant activity and their high content of vitamins. In addition, they contain a plethora of polyphenols, and they do not have high caloric content. The blossoms of Prunus dulcis (i.e., almond tree) are edible; however, they have not been examined in terms of nutritional value. The present study aimed to examine the nutritional value of almond blossoms, as well as their extracted oil. The fat content of the blossoms was 1.75 g/100 g dry weight (dw), while the defatted blossoms were found to contain 1.34 g/100 g dw of crude protein and 29.97 g/100 g dw of carbohydrates. In addition, the blossom oil was tested for its composition of fatty acids, polyphenols, and total carotenoids. According to the results, several important fatty acids for human health were identified, such as oleic (25.17%), linoleic (15.64%), and linolenic (10.15%). Simultaneously, a low oxidation index (COX), i.e., 4.05, and many monounsaturated (25.17%) and unsaturated (67.56%) fats were detected, while both polyphenols (51.86 mg GAE/kg) and carotenoids were in abundance. Finally, the combination of simple stirring with ultrasound (a green extraction method) was found to be the most appropriate method to ensure maximum amounts of various antioxidant compounds in the blossom extracts (i.e., polyphenols and L-ascorbic acid). After optimization, the total polyphenol content increased by 23.98% and L-ascorbic acid content by 6.96%. In addition, antioxidant activity was tested by different antioxidant assays and specifically FRAP, DPPH, and H2O2, which showed a corresponding increase (14.46, 17.23, and 8.79%, respectively). Therefore, it can be concluded that Prunus dulcis blossoms, besides being edible, are also highly nutritious, and their oil has nutritional value and deserves further exploration.

Physiochemical and Sensory Properties of a Turmeric, Ginger, and Pineapple Functional Beverage with Effects of Pulp Content.

Beverage mixtures based on pineapple juice (80-100%), with varying concentrations of turmeric (0-20%) and ginger (0-20%) juice were developed. The pineapple juice alone exhibited a total soluble solid (TSS) content of 15.90-16.03 °Brix. The total polyphenols content (TPC) varied between 0.32 and 1.79 mg GAE/mL, and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) inhibition was between 40.56% and 86.19% and correlated with the TPC and curcumin and other curcuminoids. The formulations with a high pulp content showed a significantly higher TPC and greater DPPH inhibition than those with a low pulp content. Turmeric and ginger with a high amount of pulp had a higher abundance of volatile compounds. Significant differences were observed by the panelists in the taste and mouthfeel attributes and the low-pulp juices were associated with increased palatability due to the better mouthfeel, higher sweetness, and decreased bitterness, pepperiness, pulpiness, and spiciness. The pineapple juice mixtures with 10% turmeric juice and 10% or less ginger juice were most preferred by sensory panelists.

Physico-Chemical, Sensory, and Nutritional Properties of Shortbread Cookies Enriched with Agaricus bisporus and Pleurotus ostreatus Powders

Mushrooms, due to their basic composition and the presence of numerous mycochemicals, can be used to improve various food matrices. The objective of this study was to determine the impact of replacing wheat flour (2%, 4%, 6% w/w) with mushroom lyophilisates from cultivated mushrooms—A. bisporus and P. ostreatus—on the technological quality, basic nutritional and elemental composition, antioxidant activity (ABTS, FRAP), total polyphenol content (TPC), and sensory evaluation of shortbread cookies. The functional properties of blended flours were also determined, such as bulk density (BD), water- and oil-holding capacity (WHC, OHC), swelling capacity (SW), and water solubility index (WSI). The results show that the amounts of protein, fiber, and ash were higher in cookies enriched with mushrooms than in control cookies. The enriched products, depending on the amount of mushroom powder used and the mushroom species, had a higher content of zinc, iron, magnesium, potassium, and copper. The increase in the addition of mushroom powder resulted in a significant (p &lt; 0.05) increase in the TPC content and antioxidant properties. The use of composite flours contributed to a significant increase in hardness (at 6% mushroom powder) and a change in color parameters, with lower whiteness and a greater ΔE recorded for cookies with A. bisporus lyophilisate. In the sensory evaluation, the samples enriched with P. ostreatus powder received higher scores compared with control samples, while the cookies with A. bisporus flour were evaluated lower than the control.

Использование процесса проращивания для повышения антиоксидантных свойств сырья

Abstract. The development of technology for controlled germination of grains and raw ingredients based on them, as well as the adaptation of methods and approaches for each individual crop, is one of the promising areas in the development of a line of food products that meets all the requirements of the modern population. The novelty of the research lies in the use of short-term temperature exposure as a disinfecting step before the process of germination of barley grain and the formation of an evidence base that this type of exposure does not have a negative impact on the remaining technological stages. The purpose of the study was to study the possibility of using barley grain in germination technology for the further production of raw ingredients with increased antioxidant properties. Research methods. The objects of study were barley grain (Hordeum vulgare L.), harvested from 2019 to 2022. The production of sprouted grain included separate technological stages: disinfection (short-term exposure to high temperatures), soaking (in water at 20 ± 2 °C for 20 hours) and germination (in a chamber with a temperature of 22 ± 2 °C and air humidity 95 ± 3 % , with a time range of 12–48 hours). Standard methods were used to evaluate: organoleptic indicators, humidity, nature, mass fraction of protein, ability and energy of germination, as well as microbiological indicators. To select the optimal duration of germination, the total content of flavonoids, polyphenols and antioxidant activity was controlled. Results. As a result of the studies, it was established that the use of short-term thermal exposure at a temperature of 190 °C and a duration of 10 s allows minimizing the risks of activating the development of the present microflora of barley grain. Using the proposed approaches, when carrying out the technological stage of germination, it was possible to identify the optimal duration of the process – 36 hours, which leads to an increase in total antioxidant activity by an average of 46 %, flavonoid content by 560 % and polyphenols by 145 %.

Kombucha as a Potential Active Ingredient in Cosmetics-An Ex Vivo Skin Permeation Study.

Kombucha is a non-alcoholic beverage, that is increasingly used in the cosmetic industry. The available literature reports the positive effects of kombucha on the skin, in particular its antioxidant action. However, there is a lack of information on skin permeation and the accumulation of active ingredients showing such effects. Skin aging is largely dependent on oxidative stress, therefore in our study we assessed the ex vivo permeation of two types of kombucha (green and black tea) through porcine skin. The antioxidant activity (DPPH, ABTS, FRAP methods) and total polyphenol content of these extracts were determined before and after permeation testing. Moreover, the content of selected phenolic acids as well as caffeine was assessed. Skin permeation was determined using a Franz diffusion cell. The antioxidant activity of both Kombuchas was found to be high. In addition, gallic acid, chlorogenic acid, protocatechuic acid, coumaric acid, m-hydroxybenzoic acid, and caffeine were identified. A 24-h ex vivo study showed the permeation of some phenolic acids and caffeine and their accumulation in the skin. Our results confirm the importance of studying the skin permeation of what are still little known ingredients in cosmetic preparations. Evaluation of the accumulation of these ingredients can guarantee the efficacy of such preparations.

Phytochemical analysis, in vitro antioxidant and antifungal activities of extracts and essential oil derived from Artemisia herba-alba Asso

Abstract Artemisia herba-alba Asso is an endemic plant from North-East Morocco offering a diverse range of pharmacological, cosmetic, and agro-ecological uses. However, Artemisia herba-alba has not been well exploited in the field of plant protection (post-harvest diseases). This is why the main objective of the present study is to evaluate the antifungal and antioxidant activities of extracts or the essential oil of this plant. Antifungal activity was assessed against Botrytis cinerea, Penicillium expansum, and Penicillium digitatum using the agar dilution method for the aqueous extracts and fumigation for the essential oil. Antioxidant activity was assessed using the DPPH scavenging test and the FRAP ferric ion reduction capacity. The chemical composition of the extracts was determined by HPLC and that of the essential oil by GC-MS/MS. In addition, the polyphenol, flavonoid, and tannin content was determined using colorimetric methods. The results of this study showed that the total content of polyphenols (217.60 mg GAE/g E), flavonoids (43.59 mg QE/g E), and tannins (32.58 mg GAE/g E) was significantly higher (p ≤ 0.05) in the ethanolic extract than in the aqueous and hexanoic extracts. Moreover, the HPLC analysis of the aqueous extract revealed the presence of six compounds, namely, catechin, gallic acid, hydroxybenzoic acid, syringic acid, caffeic acid, and rutin. In addition, the ethanolic extract was found to contain seven phenolic compounds. On the one hand, 35 compounds were identified in the essential oil of Artemisia herba-alba, representing 99.7% of the total. According to this study, the dominant compounds in the essential oil of Artemisia herba-alba Asso are camphor (46.57%), endo-borneol (5.65%), eucalyptol (5.64%), and thymol (3.85%). Furthermore, the biological evaluation showed that the extracts and essential oil of Artemisia herba-alba have significant antioxidant and antibacterial activities. The findings show that Artemisia herba-alba is a plant that can be used as a source of antifungal chemicals to prevent putrefaction of foodstuffs and, more specifically, postharvest diseases.

Wild Blackberry Fruit (Rubus fruticosus L.) as Potential Functional Ingredient in Food: Ultrasound-Assisted Extraction Optimization, Ripening Period Evaluation, Application in Muffin, and Consumer Acceptance.

The aim of the present study is to evaluate the antioxidant properties of wild blackberry fruits as well as their possible use in powdered form as a functional ingredient. For this, ultrasound-assisted extraction optimization, ripening stage evaluation, and wild blackberry powder incorporation into a real food matrix were applied. The optimum conditions for extraction were as follows: 60% MeOH, 20 min of extraction time, acidification with 0.5% HCl, and a 1:40 g/mL solid-to-solvent ratio, which allowed the following yields: total polyphenol content (TPC): 53.8 mg GAE/g; total flavonoid content (TFC): 5.78 mg QE/g; total monomer anthocyanin content (TMA): 11.2 mg CGE/g; 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (DPPH): 71.5 mg AAE/g; IC50: 52.3 µg/mL. The study also highlighted that, during the ripening process, the TPC (41.4%), TFC (17.0%), and DPPH levels (66.4%) of the fruits decreased while the TMA yield increased. The incorporation of blackberry powder at different levels (5-20%) increased the TPC, TFC, TMA, and antioxidant properties of muffins. Although the muffins enriched with 20% wild blackberry powder had the best chemical properties (TPC: 3.15 mg GAE/g; TFC: 0.52 mg QE/g; TMA: 0.23 mg CGE/g; DPPH: 1.70 mg AAE/g; IC50: 1.65 mg/mL), the sensory analysis showed that the addition of blackberry fruit at a concentration of 10% to the muffins resulted in the best consumer acceptability.

Analytical Assessment of the Antioxidant Properties of the Coneflower (Echinacea purpurea L. Moench) Grown with Various Mulch Materials.

Antioxidants are added to foods to decrease the adverse effect of reactive species that create undesirable compounds that destroy essential nutrients and, therefore, lower the nutritional, chemical and physical properties of foods. This study was carried out to determine the antioxidant properties of flowers and plant stems with leaves of Echinacea purpurea grown with mulches of different colours and thicknesses. Coneflowers were grown in the Experimental Station of the Agricultural University in Kraków, Poland. The mulching materials used were black, green and brown colours of 100 g/m2 and 80 g/m2 density. In plant material, e.g., flowers or plant stems plus leaves the proximate analysis, the total polyphenol content and the ability to scavenge free radicals (ABTS, DPPH and FRAP) were determined. The results show that flower samples had a higher content of compound proteins, ash and phenolic compounds. The mulching colour and density did not affect the proximate analysis of the E. purpurea plant. Based on the result of this study, E. purpurea is a potential source of natural antioxidants and can be used to improve the antioxidant activity of various food products as well as in cosmetics within the pharmaceutical industry.

Ion-Exchanged Clinoptilolite as a Substrate for Space Farming

Clinoptilolite, with its structural peculiarities (ion-exchange and adsorbent properties), is an excellent candidate for direct use and various modifications. In this study, we explored the effect of ion exchange and the particle size of clinoptilolite on Raphanus sativus seed germination, plant growth, physiological and biochemical characteristics of plants. Plants were grown, for three consecutive runs, on non-modified clinoptilolite, 0.9–2.5 mm (C-2.5) and 2.5–5.0 mm (C-5.0); clinoptilolite fractions modified with ion exchange with ammonium (CNH4-2.5 and CNH4-5.0); and potassium (CK-2.5 and CK-5.0) ions. Our data revealed that ion exchange with ammonium increased water-holding capacity, while potassium exchange decreased the water-holding capacity of the substrates irrespective of their particle size. The positive effect of small fractions ion-exchanged clinoptilolite (CNH4-2.5 and CK-2.5) on seed germination, during the third run, was established. The small clinoptilolite fractions favored root crop production, particularly in CK-2.5 plants only during the first run. Substantial positive effect on the content of total carbohydrates and polyphenols especially during the third run was established in plants grown on potassium-exchanged clinoptilolite. Our findings support the future exploration of clinoptilolite as a suitable substrate for plant growth in space and ground-based facilities for space-oriented experiments.