Polyphenol component and antioxidant activity of Thymus spp

This scientific work was aimed to evaluate the antioxidant potential of aromatic plants of Thymus spp. in the East of Ukraine. These plants are known as medicinal and food around the world. All antioxidant parameters were investigated spectrophotometrically: total content of polyphenols (TPC), the total content of phenolic acids (TPAC), the total content of flavonoids (TFC), molybdenum reducing power of extracts (MRP), and antioxidant activity by DPPH method (DPPH). Investigation of ethanolic extracts demonstrated that TPC varied from 57.89 to 123.67 mg/g gallic acid equivalent (GAE) DW for Th. pulegioides, from 61.43 to 168.18 mg GAE/g for Th. serpyllum, and from 47.36 to 115.67 mg GAE/g for Th. vulgaris. TPAC ranged from 27.36 to 50.22 mg/g caffeic acid equivalent (CAE) DW for Th. pulegioides, from 28.58 to 59.62 mg CAE/g for Th. serpyllum, and from 22.95 to 53.82 mg CAE/g for Th. vulgaris. TFC was determined in a range from 29.88 to 61.23 mg/g quercetin equivalent (QE) DW for Th. pulegioides, from 36.0 to 82.43 mg QE/g for Th. serpyllum, and from 24.59 to 55.41 mg QE/g for Th. vulgaris. MRP was detected in the range of 94.65 – 204.76 mg/g Trolox equivalent (TE) DW for Th. pulegioides, 96.06 – 219.0 mg TE/g for Th. serpyllum, and 87.56 – 215.43 mg TE/g for Th. vulgaris. The antioxidant activity of extracts by the DPPH method was 6.34 – 9.23 mg TE/g for Th. pulegioides, 8.11 – 9.21 mg TE/g for Th. serpyllum, and 4.97 – 9.53 mg TE/g for Th. vulgaris. It was established that polyphenol accumulation depended on the growth stage and species. For all species was found a strong correlation between TPC and TFC (r=0.938, 0.908, and 0.854). Investigated Thymus spp. are a valuable source of antioxidants that can be used in pharmacological studies and the food industry.

Phenolic content and antioxidant activity of Echinocystis lobata (Mich.) Torr. ET Gray (Cucurbitaceae)

Echinocystis lobata (Mich.) Torr. et Gray extracts were investigated for their bioactive compounds and their potential for natural antioxidant properties. In vitro antioxidant activity of methanol, ethanol, and water extracts were evaluated by 1,1-diphenyl-picrylhydrazyl (DPPH) radical scavenging activity. Total phenolic content (TPC) and total flavonoid content (TFC) of fruits and seeds were determined. TPC is a fairly constant value and varies weakly both among the different organs of Echinocystis lobata and among the geographical locations of the populations studied. Like other invasive species, Echinocystis lobata is superior to many other plants in terms of the total amount of flavonoids contained in its fruits and seeds. The dried fruits contain more flavonoids than the seeds. Seeds from Slovak populations have higher flavonoid content than those from Russian populations. The results demonstrated that Echinocystis lobata can be a good source of natural antioxidants and have a great potential for commercialization, especially in the pharmaceutical industry.

Wild Sambucus nigra L. from north-east edge of the species range: A valuable germplasm with inhibitory capacity against SARS-CoV2 S-protein RBD and hACE2 binding in vitro

Berries and flowers of Sambucus nigra L. tree are well known for their ability to mitigate symptoms of upper respiratory disorders related to reported antiviral properties. Industrial application and commercial cultivation of S. nigra is largely limited to a few widely grown cultivars. Restricted genetic diversity of cultivated S. nigra can be disadvantageous if new industrial applications are discovered. In this study wild S. nigra populations located on the north-east edge of the species natural range were explored by assessing genetic origin, berry and flower anti-oxidative potential, and berry rutin content. Best performing wild S. nigra extracts were selected for an assessment of previously unreported biological activity- inhibitory capacity against SARS-CoV2 S1 protein receptor binding domain (RBD) binding to recombinant human angiotensin -converting enzyme 2 (ACE2) receptor in vitro based on competitive enzyme linked immunosorbent assay (ELISA). Inter-simple sequence repeat (ISSR) marker-based genetic characterization suggested that explored wild S. nigra populations result from wild gene pool expanding northwards with admixture of historically introduced cultivated S. nigra. Average values of total phenolic content, anti-radical activity, and total flavonoids content of wild S. nigra populations did not exceed those of cv. 'Haschberg'. Concentration-dependent inhibition of ACE2-SARS-CoV2 S-protein RBD binding was demonstrated in vitro for elderberry fruits and flowers extracts (IC50 of 1.66 mg DW ml^-1 and 0.532 mg DW ml^-1, respectively). Wild elderberry fruit extract exhibited higher inhibitory capacity than the extract from berries of cv 'Haschberg'. This study validates the requirement for S. nigra wild germplasm bioprospecting and opens up directions for further research of new anti-SARS-CoV2 industrial applications of S. nigra.

Studies on the chemical composition of fruits and seeds of Pseudocydonia sinensis (Thouin) C.K. Schneid

Pseudocydonia sinensis (Thouin) C. K. Schneid. less known plant species in the Ukraine conditions, but the fruits were widely used in traditional Chinese medicine for the treatment of asthma, colds, sore throat, mastitis, rheumatoid arthritis, and tuberculosis. The content of protein, ash, and lipids in the seeds was found to be greater than in the pulp and peel. Monosaccharide analysis of neutral carbohydrate part showed the presence of two main sugars fructose and sucrose in the seeds, pulp, and peel. There is a higher beta-carotene content in the rind of the fruit than in the seeds and pulp. The total amount of fatty acids varied from sample to sample and contained mainly oleic acid, palmitic acid, linolenic acid, and linoleic acid. Linoleic acid in the seeds was 48.02% of total fatty acids, slightly less in the rind 42.70%. Palmitic acid, oleic acid, and linoleic acid in the pulp samples were 45.38, 21.32, and 14.93%, respectively. The total amount of amino acids found in the seeds was 105.0 g.kg-1 DM, including total essential amino acids (32.70 g.kg-1 DM). Glutamic acid was found in seeds to be the dominant free amino acid followed by aspartic acid and arginine in the seed. In our study, the antioxidant activity carried out by the DPPH method and measured by molybdenum reducing antioxidant power of peel, pulp and seeds were 9.41, 7.08, 6.21, and 158.81, 92.83, 78.58 mg TEAC.g-1 DM, respectively. Micro and macronutrients and amino acids predominated in the seeds, total fatty acids predominated in the pulp. The highest content of bioactive compounds (total polyphenols, flavonoid, and phenolic acid) and antioxidant activity was found in the peel. P. sinensis can be considered as a nourishing fruit with a copious potential with health-promoting roles and medicinal properties.

Biochemical characterization of fruits of Lycium spp. in Ukraine

Fruits of Lycium possess therapeutic properties due to which they are used in traditional and folk medicine and can be used as a kind of functional food. The objective of this study was to evaluate the biochemical characterization of Lycium L. (L. barbarum L., L. chinense Mill. and L. truncatum Y. C. Wang) fruits for 16 cultivars and varieties from the collections in the M. M. Gryshko National Botanical Garden of NAS of Ukraine (Kyiv). This study was aimed at determining the concentration of nutrients in the Lycium fruits. Individual genotypes of three Lycium species: L. barbarum, L.chinense, and L. truncatum, differed in such features as the content of dry matter, sugars, vitamin C, β-carotene, acidity, and tannins in the fruit. Fruits of Lycium spp. are a valuable source of nutrients such as vitamin C (4.38–121.0 mg 100g–1 FW), β-carotene content (1.45–5.52%), and tannin (0.12–1.34%). The sugar content (13.83–20.87%) and acidity of the fruit (0.23–4.62%) meet the consumers' requirements for fresh fruit. The cultivar Amber Sweet (L. chinense) had fruits of which the similarities between biochemical characteristics of different studies genotypes were the lowest. The cv. Amber Sweet was characterized by fruit with high sugar content, very high vitamin C content, average acid content, low tannins and β-carotene content, and the lowest dry matter content. Furthermore, a distinctive feature of the other tested genotypes was the yellow colour of the fruit. The data obtained can be used for further selective work.

Estimation of phenolic compounds content and antioxidant activity of leaves extracts of some selected non-traditional plants

The aim of the research is the determination of the total antioxidant activity and the content of phenolic compounds of the leaves of 12 species of non-traditional plants, namely, Amelanchier alnifolia (Nutt.) Nutt. ex M. Roem., Aronia mitschurinii A.K. Skvortsov & Maitul., Castanea sativa Mill., Chaenomeles japonica (Thunb.) Lindl., Cornus mas L., Diospyros kaki L., Diospyros lotus L., Diospyros virginiana L., Lycium barbarum L., Lycium сhinense Mill., Pseudocydonia sinensis (Thouin) C.K. Schneid., Ziziphus jujuba Mill. Total phenolic content was evaluated using the Folin-Ciocalteu reagent assay. Antioxidant activity was measured using two different methods (DPPH – 2,2-diphenyl-1-picrylhydrazyl, MRAP – molybdenum reducing antioxidant power). Significant variability was observed in phenolic compounds content and total antioxidant activity. Total polyphenol content ranged from 38.02 (Z. jujuba) to 80.58 (C. sativa) mg GAE.g-1 DM, total flavonoid content from 22.47 (P. sinensis) to 54.61 (L. barbarum) mg QE.g-1 DM and phenolic acids content from 3.51 (A. mitschurinii) to 24.67 (Ch. japonica) mg CAE.g-1 DM. All tested samples exhibited DPPH• radical scavenging activities with values from 6.92 (A. mitschurinii) to 9.0 (C. mas) mg TEAC.g-1 DM. Antioxidant activity by molybdenum reducing antioxidant power method ranged from 109.43 (A. mitschurinii) to 322.95 (C. mas) mg TEAC.g-1 DM. Differences between the species of non-traditional plants were significant in all observed parameters. Obtained results of phytochemical composition demonstrated the possibility of leaves' use of non-traditional plants as sources of valuable bioactive compounds with health-promoting and disease-preventing properties.

Comparative analysis of antioxidant activity and phenolic compounds in the fruits of Aronia spp

Chokeberry (Aronia Medik.) is a non-traditional fruit plant known as a rich source of biologically active compounds and inhibits the numerous biological activities. We compared the antioxidant activity and phenolic compounds of fruits between widely cultivated Aronia mitschurinii (AM-TCH, from Tchekhov district; AM-D, from Dmitrov district; AM-OZ, from Orekhovo-Zuevsky district of Moscow region, Russia) and introduced North American Aronia species (Aronia arbutifolia (AA-M), A. melanocarpa (AML-M), A. × prunifolia (AP-M), which have not been planted yet in the arboretum of Main Botanical Garden of the Russian Academy of Sciences (Moscow). Studying samples were collected in their secondary distribution range. Ethanolic extracts were determined for antioxidant capacity (antioxidant activity by DPPH and phosphomolybdenum methods, the total content of polyphenols, flavonoids, phenolic acids) and measured spectrophotometrically. As standards were used Trolox (TE) for antioxidant activities, gallic acid (GAE) for polyphenol content, quercetin (QE) for flavonoid content, caffeic acid (CAE) for phenolic acid content. The antioxidant activity by DPPH method in ethanol extracts of investigated plants was from 6.96 (AM-D) to 8.89 (AM-OZ) mg TE.g-1 DW. Reducing the power of investigated extracts exhibited activity from 151.47 (AM-OZ) to 297.8 (AA-M) mg TE.g-1 DW. The content of polyphenol compounds determined from 25.98 (AM-TCH) to 54.39 (AA-M) mg GAE.g-1 DW, phenolic acids content was from 7.76 (AP-M) to 11.87 (AM-D) mg CAE.g-1 DW and the content of flavonoids detected from 8.12 (AM-OZ) to 16.62 (AM-D) mg QE.-1 DW. Obtained data showed a strong correlation between the content of polyphenol compounds and reducing the power of extracts (r = 0.700), between flavonoids and phenolic acids (r = 0.771) and also between phenolic acids and reducing power (r = 0.753) in Aronia ethanol extracts. Fruits of investigated species of Aronia can be propagated as a source of polyphenol compounds with antioxidant activity and obtained results may use for farther pharmacological study.

Evaluation of the physiological state of feijoa (Feijoa sellowiana Berg) in subtropical Russia

The article presents the results of research examining varietal diversity with respect the activity of oxidative enzymes (EC 1.11.1.6) and the dry matter and Proline accumulation of leaves under optimal and stressful conditions. For feijoa, the most stressful period in the subtropics of Russia, with respect to hydrothermal conditions, occurs between July and September. Studies have shown that the highest degree of enzymatic activity is observed in August in the ‘Superba’ variety of feijoa, which was used as a control in this study, and the lowest level of activity was observed in the 'Sentjabrskaja' variety. The long-term water deficit experienced in September coincides with fruiting in feijoa. This causes a change in catalase activity in leaves, which is maintained until it is inhibited. Form ShV-1 of feijoa is characterised by its metabolic stability. In fact, the activity of oxidative enzymes in leaves of the variety is stable. Dry matter content per unit area increases as the leaf grows. During the drought period, which coincides with active fruiting, the leaves of the ‘Dachnaja' variety and the ShV-1 form accumulate significantly less dry matter than other varieties. In the ‘Dagomysskaja' variety, the intensity of organic matter consumption via respiration and outflow exceeds visible photosynthesis, which is expressed as a negative value (average = 1.96 g.dm-2 h). To fully characterise the physiological state of feijoa plants under the influence of abiotic factors and catalase activity in the humid subtropics of Russia, indicators of dry matter accumulation and true photosynthesis intensity can be used.

Parameters of antioxidant activity of Galega officinalis L. and Galega orientalis Lam. (Fabaceae Lindl.) plant raw material

The plant raw material of Galega officinalis L. (goat’s rue) and Galega orientalis Lam. (fodder galega) investigated in this study. These species are known as fodder crops with high productivity of green mass and as medicine plants. The current study was aimed to evaluate an accumulation in dry raw of selected plants the total content of phenolic acids (TPA) and flavonoids (TFC) as compounds with antioxidant activity (AA) by spectrophotometric method. AA by DPPH-method and phosphomolybdenum method (reducing power (RP)) was measured. Study of ethanolic extracts of G. officinalis showed accumulation of TPA in different organs in range from 3.65 to 15.17 mg.g-1 caffeic acid equivalent (CAE) and TFC from 10.08 to 65.75 mg.g-1 quercetin equivalent (QE), AA by DPPH-method from 6.02 to 8.45 mg.g-1 Trolox equivalent (TE) and RP of extracts by phosphomolybdenum method from 86.56 to 288.15 mg TE.g-1. In extracts of G. orientalis was identified TPA from 3.52 to 18.52 mg CAE.g-1 and TFC from 6.09 to 46.72 mg QE.g-1, antioxidant activity by DPPH-method from 6.80 to 8.48 mg TE.g-1 and antioxidant capacity by phosphomolybdenum method from 52.52 to 188.51 mg TE.g-1. It was established that less concentration of studied compounds found in the stems for both species. It should be noted that the content of phenolic acids in the leaves was decreased and flavonoids in stems increased during vegetation for both species. Content of phenolic acids in the generative organs and flavonoids in the leaves decreased in raw of G. orientalis during vegetation. Pearson’s correlation analysis demonstrated very strong relations between TFC and AA by DPPH, TPA and RP, TFC and RP for G. officinalis extracts. Very strong correlation in the extracts of G. orientalis found between TFC and RP, TPA and RP. Obtained results can be used in the further biochemical and pharmacological study.

Morphological and antiradical characteristics of Rugosa rose (Rosa rugosa Thunb.) fruits canned in different kind of honeys and in beverages prepared from honey

The aim of the work was to determined the basic morphological and morphometric traits of rugosa rose (Rosa rugosa Thunb.) and antiradical activity of fruit pulp canned in different kind of honeys and in beverages prepared from honey. In experiments there were used 4 genotypes of roses originated from arboretum Mlyňany (Slovakia). The evaluation of 11 morphometric traits of fruit showed that the average weight of the fresh fruit without pedicle reached up 5.14 - 5.46 g, the weight of pedicle was 0.05 - 0.08 g, weight of pulp and seeds 4.80 - 5.13 g, weight of calyx 0.25 - 0.31 g, length and width of fruit (16.10 - 18.13 mm, 21.38 - 22.46 mm), the number of seeds in fruit 48.45 - 71.05, thickness of pulp 2.63 - 2.97 mm. Separated fruit pulp was canned at 40 °C and 80 °C and premixed in robinia honey and honeydew honey. Beverages were prepared by mixture of fruit pulp in honey (15 g) with cold water (150 mL). Antiradical activity was determined by DPPH method in fruit pulp (in methyl alcohol and water extracts), in honeys (black locust honey and honeydew honey) and beverages. There had been confirmed statistically significant differences in morphological traits, especially in colour and shape of fruit. Antiradical activity of fresh fruit pulp in methyl alcohol extract was determined 94.59%, in water extract 89.71%. Antiradical activity of black locust honey was 7.63%, honeydew honey 6.54%. Antiradical activity was determined also adding honeydew honey and black locust honey to fresh pulp of fruit prepared at 80 °C (33.55% and 77.58%). In beverages prepared from fresh pulp, honey and water it was investigated the higher values of antiradical activity in samples with addition of honeydew honey (81.81 - 83.86%) in comparison with robinia honey (75.57 - 79.96%).

Variation of fruits morphometric parameters and bioactive compounds of Asimina triloba (L.) Dunal germplasm collection

The objective of this study was to evaluate the morphological parameters and bioactive compounds (antioxidant activity, total polyphenol, flavonoid, and phenolic acid content) of 6 genotypes of dry Asimina triloba (L.) fruit from Slovak University of Agriculture in Nitra (Slovakia). Genotypes were obtained from the seeds that were sown in the year 2000. Their morphometric parameters were following: fruit weight from 59.00 to 241.19 g, fruit length from 50.14 to 140.11 mm, fruit diameter from 37.55 to 64.67 mm, number of fruits per cluster from 2 to 8, seed weight from 0.06 to 1.80 g, seed length from 16.33 to 29.11 mm, seed width from 9.56 to 18.33 mm, seed thickness from 4.98 to 9.75 mm, number of seeds in fruit from 4 to 16. The shape indexes of fruits were found ranging from 1.53 to 2.16. The variability of important is the average seeds weight from 7.40 to 35.61%, fruit weight from 14.84 to 32.95%, number of fruits per cluster from 18.21 to 32.54% and a number of seeds in fruit from 13.49 to 27.72%. The other characteristics are more or less stable. Total polyphenol content ranged from 22.13 to 37.36 mg GAE per g, total flavonoid content from 15.10 to 32.03 mg QE per g and phenolic acids content from 0.23 to 0.76 mg CAE per g. All tested samples exhibited DPPH radical scavenging activities with values from 2.84 to 7.04 mg TEAC per g. Antioxidant activity by molybdenum reducing antioxidant power method ranged from 97.25 to 275.41 mg TEAC per g of dry matter. Differences between the genotypes were significant in all observed parameters. This species is potential for propagation and practice used in the Slovak Republic.