Composition Of Phenolic Compounds Research Articles

Research in phytochemical composition and hypoglycemic activity screening of the dry extracts from bearberry leaves

Diabetes mellitus is a global medical and social issue. In the developed countries of the world, from 5 to 12% of the population are diagnosed with diabetes mellitus and, according to WHO prognosis, the level of this disease may increase to 30-35%. Type 2 diabetes is a disease that progresses over time, but the rational and systematic use of hypoglycemic synthetic drugs and phytopreparations can significantly delay the onset of insulin therapy. A promising source of BAS with a hypoglycemic effect is the raw material of plants of the Heather family, namely, bearberry leaves. However, on the Ukrainian market there are no domestic galenic and novo-galenic preparations based on biologically active substances of this raw material, which indicates the prospects for the development of new drugs, including those with hypoglycemic action. The aim. The aim of the study was to study the phytochemical composition and to carry out a screening of the hypoglycemic activity of dry extracts from bearberry leaves modified with various amino acids to identify promising substances with hypoglycemic action. Materials and methods. The objects of the study were 11 dry extracts from bearberry leaves, 10 of which were modified with various amino acids. The study of the phenolic compounds of the extracts was carried out by TLC, HPLC, and spectrophotometry. To assess the hypoglycemic activity of the extracts, two experiments were carried out - primary screening and oral glucose tolerance test. Results. Using TLC and HPLC, in the extracts obtained arbutin, gallic acid, 5 flavonoids were identified, among which hyperoside was dominant, 4 hydroxycinnamic acids, among which chlorogenic and caffeic acids were dominant, and their content was established. In the extracts obtained, main groups of phenolic compounds were quantified using a spectrophotometric method. Dry extracts from bearberry leaves, modified with cysteine, arginine and glutamic acid, showed the strongest hypoglycemic activity. Conclusions. The chemical composition of phenolic compounds and the hypoglycemic activity of dry extracts from bearberry leaves modified with 10 different amino acids were determined. The most promising substances turned out to be extracts modified with cysteine, arginine and glutamic acid; therefore, they are promising agents for the development of new drugs.

Glycoside Hydrolases and Non-Enzymatic Glycation Inhibitory Potential of Viburnum opulus L. Fruit-In Vitro Studies.

Phytochemicals of various origins are of great interest for their antidiabetic potential. In the present study, the inhibitory effects against carbohydrate digestive enzymes and non-enzymatic glycation, antioxidant capacity, and phenolic compounds composition of Viburnum opulus L. fruits have been studied. Crude extract (CE), purified extract (PE), and ethyl acetate (PEAF) and water (PEWF) fractions of PE were used in enzymatic assays to evaluate their inhibitory potential against α-amylase with potato and rice starch as substrate, α-glucosidase using maltose and sucrose as substrate, the antioxidant capacity (ABTS, ORAC and FRAP assays), antiglycation (BSA-fructose and BSA-glucose model) properties. Among four tested samples, PEAF not only had the highest content of total phenolics, but also possessed the strongest α-glucosidase inhibition, antiglycation and antioxidant activities. UPLC analysis revealed that this fraction contained mainly chlorogenic acid, proanthocyanidin oligomers and flavalignans. Contrary, the anti-amylase activity of V. opulus fruits probably occurs due to the presence of proanthocyanidin polymers and chlorogenic acids, especially dicaffeoylquinic acids present in PEWF. All V. opulus samples have an uncompetitive and mixed type inhibition against α-amylase and α-glucosidase, respectively. Considering strong anti-glucosidase, antioxidant and antiglycation activities, V. opulus fruits may find promising applications in nutraceuticals and functional foods with antidiabetic activity.

Evaluation of phenolic composition and antioxidant properties of different varieties of Chinese citrus

Citrus peels have health-promoting effects and are a rich source of antioxidant substances. This study evaluated the compositions of phenolic compounds and antioxidant activities in the peels of 52 citrus varieties with consistent planting time and management. The highest levels of total phenols (72.95 ± 37.60 mg/g DW) and total flavonoids (71.43 ± 37.64 mg/g DW) were found in mandarin. The highest phenolic acid content (18.78 ± 0.38 mg/g DW), dominated by protocatechuic acid, was found in kumquat. The antioxidant potency composite index was 6.23–94.56, suggesting mandarin varieties HJ, TWPG, TTPG, AY28, BZH and TCJC had the highest antioxidant activity. Statistics analysis indicated phenolic compounds and antioxidant activity were positively correlated. Principal component analysis and hierarchical cluster analysis suggested a strong relationship between phenolic compound composition and genetic background. This study indicated significant differences in the biological properties of various types of citrus peels; which are valuable for future utilization and research of citrus peels.

Impacts of added oenological tannins on red wine quality to counteract <i>Botrytis</i> infection in Merlot grapes

The contamination of grape berries by Botrytis cinerea can drastically damage wine quality, in particular causing colour degradation. In musts obtained from botrytised grapes, SO2 addition is the main means of avoiding oxidation damage due to laccases excreted by the pathogen. However, consumers are becoming increasingly reluctant to accept SO2 addition to wine. Oenological tannins are used for fining wines because of their colloidal properties, and for wine colour stabilisation due to their ability to condense with anthocyanins. They are also known for their antioxidant and antioxidasic properties. They were thus investigated in the present study for their potential as an alternative to SO2 against laccase oxidation.The impact of various types of oenological tannins on musts and wines was studied once added to musts obtained from the Merlot cultivar, comprising 20 % and 50 % botrytised grapes. Laccase activity, antioxidant capacity, composition of phenolic compounds, spectrophotometric and CIELAB colour parameters were assessed in the musts and wines. Sensory analyses were also performed on 3-month-old wines to evaluate the visual, olfactory and gustative consequences of tannin addition. At a 50 % botrytisation rate, the addition of any type of oenological tannins (at a concentration of 100 g/hL) had no effect on laccase activity and did not protect phenolic compounds. However, at the same concentration and at a 20 % botrytisation rate, proanthocyanidin tannins from grape skin were found to be the most promising tannins with simultaneous protective effects, such as an inhibitory effect on laccase enzymes, protection of colour from complete degradation and preservation of some procyanidin compounds.Oenological tannins are promising candidates for protecting wines from Botrytis damage and they induce a differential effect according to their origin and structure. They could be used to reduce the amount of SO2 that is added during vatting. More research is needed to confirm and better understand the mode of action of various tannins at levels lower than the 20 % botrytised rate tested in the present study.

Composition of Phenolic Compounds, Cyanogenic Glycosides, Organic Acids and Sugars in Fruits of Black Cherry (Prunus serotina Ehrh.)

The forest understory is rich in fruit-bearing trees and shrubs. They include both native species and invasive alien plant species (IAPS). One of the most spreading IAPS is black cherry (Prunus serotina E.). Problems with the invasiveness of P. serotina is well known in many European countries. However, there are very few studies related to this IAPS. This article aims to fill the gap in research on the bioactive compounds of black cherry fruits and thus to start a discussion on the potential use of this species on an industrial or semi-industrial scale, which may lead to the reduction of this species presence in forests. Fruits were collected in a forest of Northern Poland. Contents of sugars, phenolic compounds as well as cyanogenic glycosides were determined. Pphenolic compounds and cyanogenic glycoside were assayed using HPLC-DAD coupled with MSn. Sugars and organic acids were determined with the use of HPLC-DAD. Fruits of P. serotina can be considered as rich in anthocyanins, even at a lower level of total phenolics than in their plantation-grown couterparts, fruits of black cherry are still a good source of dietary phenolics of natural, forest-grown origin. When stones are not crushed during processing the level of GCC is within a safe, admissible range.

Impact of Commercial Yeasts on Phenolic Profile of Plavac Mali Wines from Croatia

Wine quality is influenced by the presence of over 500 different chemical compounds, with polyphenols having a crucial role in color intensity and tonality, astringency, mouthfeel, and overall impression formation, especially in red wine production. Their concentrations in wine can vary notably depending on the grape variety, the temperature and the length of maceration process, aging duration, and yeast selection. Therefore, in this work, the main goal was to determine the influence of five commercially available Saccharomyces yeasts provided from Lallemand, France and AEB, Italy, on the phenolic compound composition and chromatic parameters of Plavac mali wines produced from the grapes from coastal Dalmatia, grown at two different micro-locations. The achieved results pointed out the marked difference in individual polyphenol compound adsorption between tested yeasts. Fermol Super 16 was the one with the lowest and Lalvin D21 the strongest adsorption ability, regardless of vine growing location. These differences can be explained by the content of some anthocyanins (delphinidin and petunidin-3-O-glucoside) and gallic acid, and some flavan-3-ols. Tested strains also influenced wine color intensity, pointing out the possibility of modulating the style of a Plavac mali by the use of commercial yeasts.

Metabolomic Profiling, Antioxidant and Antimicrobial Activity of Bidens pilosa

Bidens pilosa L. (fam. Asteraceae) is an annual herb used globally in phytotherapy and each plant material or the whole plant have been declared to be effective. Therefore, the aim of the present study was to conduct metabolomic profiling of different plant materials, including the quali-quantitative composition of phenolic compounds. The intrinsic scavenging/reducing properties and antimicrobial effects of the extracts were assayed against numerous bacterial, Candida and dermatophytes species, whereas docking runs were conducted for tentatively unravelling the mechanism of action underlying antimicrobial effects. Oligosaccharide, disaccharide and fatty acids were present at higher concentrations in root rather than in the other plant parts. Monoglycerides were more abundant in stem than in the other plant parts, whereas peptide and diterpenoid were prominent in leaf and root, respectively. By contrast, amino acids showed very different distribution patterns in the four plant parts. Regarding the phenolic composition, appreciable levels of caftaric acid were found in most of the analyzed methanol extracts, that were also particularly efficacious as antiradical and anti-mycotic agents against C. albicans and dermatophytes. The docking experiments also showed a micromolar affinity of caftaric acid towards the lanosterol 14α-demethylase, deeply involved in fungal metabolism. In conclusion, the present study corroborates the B. pilosa as a phytotherapy remedy against infectious disease.

The content of phenolic compounds in the leaves of Paeonia suffruticosa Andr. and their antioxidant activity

The tree peony, which is considered a traditional ornamental plant in China, Japan, America and Europe, is also widely used as a medicinal plant. The collection of tree peonies in the State Scientific Institution “Central Botanical Garden of the National Academy of Sciences of Belarus” is represented by four taxa. The aim of our work was to assess the quantitative composition of the sum of phenolic compounds and hydroxylcinnamic acids in the leaves of the genus Paeonia, as well as to assess the antioxidant status of these samples depending on the phase of ontogenesis. As a result of the studies, a high content of phenolic compounds and hydroxycinnamic acids in the leaves of the studied taxa of the genus Paeonia was established, including the content exceeding the threshold of 65 mg/g in the leaves of Paeonia suffruticosa in all observed phases of ontogenesis. In the studied varieties, the proportion of hydroxycinnamic acids in the composition of phenolic compounds ranged from 25 to 50 %. Extracts of leaves of the Paeonia genus collected during the flowering period had the maximum antioxidant activity. Thus, the above data indicate that the aerial part of the Paeonia genus can be considered as a promising raw material for the creation of herbal remedies with antioxidant action.

Steam explosion pretreatment alters the composition of phenolic compounds and antioxidant capacities in Chrysanthemum morifolium Ramat cv . “Hangbaiju”

Steam explosion has gained much attention in the food industry. This study aimed to investigate if steam explosion could change the composition of phenolic compounds and antioxidant feature of a Chinese indigenous herb “Hangbaiju” (HBJ). Results showed that the color attributes, microstructure, and composition of phenolic compounds of HBJ were altered after the pretreatment. With the increasing pressure and duration, the contents of 3- and 4-O-caffeoylquinic acid increased. Meanwhile, some flavone aglycones, such as apigenin, luteolin, and acacetin, showed content increases, whereas apigenin-7-O-glucoside, luteolin-7-O-glucoside, and diosmetin-7-O-glucoside showed content increases and then decreases. Furthermore, 3,5-O-caffeoylquinic acid and 5-O-caffeoylquinic acid exhibited content reduction. Some caffeoylquinic acids exhibited the structural rearrangement and degradation during the steam explosion, which also hydrolyze flavone glycosides to flavone aglycones. Hence, steam explosion pretreatment is suitable for the extraction of 3-O-caffeoylquinic acid, 4-O-caffeoylquinic acid, and some flavone aglycones, as well as the modification of HBJ samples. Novelty impact statement Steam explosion altered the appearance of “Hangbaiju” and disrupted its microstructure. Different pressure and duration of steam explosion showed different effect on phenolic compounds composition and antioxidant capacities of “Hangbaiju.” Furthermore, steam explosion pretreatment increased flavone aglycones content in “Hangbaiju.”

Phenolic Composition and Antioxidant Activity of Plants Belonging to the Cephalaria (Caprifoliaceae) Genus.

The genus Cephalaria, belonging to the Caprifoliaceae family, is a rich source of interesting secondary metabolites, including mainly saponins which display a variety of biological activities, such as immunomodulatory, antimicrobial and hemolytic effects. Besides these compounds, flavonoids and phenolic acids were identified in Cephalaria species. Cephalaria is employed in traditional medicine e.g., to cure cardiac and lung diseases, rheumatism, and regulate menstruation. In this review we focus on the phenolic compound composition and antioxidative activity of Cephalaria species. The antioxidant effect can be explained by flavonoids present in all parts of these plants. However, future efforts should concentrate more on in vitro and in vivo studies and also on clinical trials in order to confirm the possibility of using these plants as natural antioxidants for the pharmacology, food or cosmetic industries.

Antimicrobial Activity and Polyphenol Profiles of Hydroalcoholic Extracts of Thymus rasitatus Klokov and Thymus eremita Klokov

BACKGROUND: A possible reduction in stocks of medicinal plant raw materials of Thymus serpyllum L. and Thymus vulgaris L. leads to the need to expand the raw material base of the official medicinal plants with using of endemic species of the flora of Kazakhstan, in particular, Thymus rasitatus Klokov, and Thymus eremita Klokov. AIM: The aim of the study was to study the possibility of using 70% ethanol extracts of T. rasitatus and T. eremita as antimicrobial agents. MATERIALS AND METHODS: The aerial parts of T. rasitatus and T. eremita were extracted with 70% ethanol using ultrasound assisted extraction. The qualitative and quantitative analyses of the 70% ethanol extracts were determined using the liquid chromatography-detection-ESI-mass spectrometry-(MS)/MS technique. The study of the antimicrobial activity of these extracts was performed for eight strains of Gram-positive bacteria, six strains of Gram-negative bacteria, and four cultures of fungi. RESULTS: Chromatographic analysis of hydroalcoholic extracts of both investigated Thymus species showed very similar phenolic compounds composition. In both cases, the major components are luteolin-7-O-glucoside and rosmarinic acid. About 70% ethanol extracts of T. rasitatus and T. eremita have a broad spectrum of antimicrobial activity, exhibit the bactericidal or bacteriostatic activity against all tested bacteria and fungi at concentration range of 0.0195–20 mg/ml, but differ in their potency against tested strains of microorganisms. CONCLUSION: About 70% ethanol extracts of T. rasitatus and T. eremita, endemic plants in the flora of Kazakhstan, can be considered as potential drugs with a wide spectrum of antimicrobial activity. The results of chromatographic analysis could be used for drug standardization.

Environment rather than provenance explains levels of foliar phenolics in European beech (Fagus sylvatica L.) seedlings

With progressive climate change, the chemical defense in European beech (Fagus sylvatica L.) is likely to change, which might impact its fitness and ability to establish beyond its current northern distribution limit. We studied the phenolic defense in six beech provenances grown in three common gardens in Norway the two first years after planting.We analyzed low molecular weight phenolic compounds by HPLC and condensed tannins by the acid-butanol assay. Sampling year explained most of the variance in phenolic defense, followed by environment (growing location), while the genetic background (provenance) showed the least explanatory power. After the first year in the field, the northernmost growing location had about 70% higher concentration of low molecular weight phenolics than the southern growing locations. The concentrations of condensed tannins, however, were lowest in the north. The mean concentration of total low molecular weight phenolics was twice as high after the first year compared to the second year. After the second year, the differences between the growing locations in many cases disappeared. The differences between the growing locations are probably caused by differences in temperature and soil fertility, while we attribute the decrease in low molecular weight phenols from the first to the second year to decreased water and nutrient stress, as well as aging. Our results suggest that intraspecific variations in concentration and composition of phenolic compounds in beech are caused by differences in the environment to a greater extent than the genetic background, which may indicate fast changes in chemical defense with climate change.

Growth and Biosynthetic Characteristics of Phlojodicarpus sibiricus Cell Suspension Cultures

Features of the growth and qualitative composition of secondary metabolites in two lines of suspension cell cultures of Phlojodicarpus sibiricus (Steph. ex Spreng.) K.-Pol., an endangered endemic species of Eastern Siberia, have been studied. A suspension cell culture of leaf origin demonstrated the best growth characteristics, which included growth indices for different criteria (dry and crude biomass and cell concentration): I = 10–14; specific growth rate μ = 0.3–0.4 day–1; the maximum dry biomass accumulation М = 9.6 g/L and economic coefficient Y = 0.29. A plant cell culture derived from a hypocotyl was characterized by lower growth parameters: I = 3.6–4.9, μ = 0.12–0.18 day–1, M = 6.6 g/L, Y = 0.16. Differences in the growth of the studied cultures correlated with the cell aggregation level: the “leaf” culture consisted mainly of small-size aggregates (10–30 cells), whereas the “hypocotyl” culture was presented by large aggregations (50 cells or more). The instrumental cultivation of the small-aggregated suspension cell culture of leaf origin was carried out using two types of laboratory bioreactors (bubble column and stirred tank). Cultivation in a bubble column reactor improved the basic growth characteristics of the cell culture: the growth index for the dry biomass I = 12.7; dry biomass productivity P = 0.78 g/L day, μ = 0.18 day–1, М = 15.8 g/L, Y = 0.49. In the case of a stirring tank reactor, all growth parameters were decreased, which was probably connected with the cell damage with stirring devices. Additionally, a phytochemical analysis of the secondary metabolite composition in the studied cell cultures was carried out in comparison with the root cells of intact Ph. sibiricus plants. Significant differences in the composition of phenolic compounds were revealed between in vitro cell cultures and plant roots. In the case of cell cultures, polar (hydrophilic) compounds belonging to phenolic derivatives (coumarin glycosides and benzofurans) prevailed. In roots, the main components were more hydrophobic (khellactone ethers). The obtained results confirmed the earlier developed concept of differences in the secondary metabolism of in vitro and in vivo plant cells.

Health Benefits of Cornelian Cherry (Cornus mas L.)

Medicinal plants have been used for medical objectives since ancient times due to their beneficial properties, and their uses continue to this day. The Cornelian cherry fruit (Cornus mas L.) is considered to be one of those medicinal plants with important nutritional and therapeutic properties. It has been also used for different medical purposes in many countries in Europe and Asia for centuries due to its various important components in terms of health. Cornelian cherry is known to have antimicrobial, antioxidant, anticancer and anti-inflammatory effects due to its composition of phenolic compounds and ursolic acid. It is reported in the literature that This fruit is used in different countries for different purposes; for the treatment of intestinal and kidney diseases, strengthening immunity, and preventing some types of cancer and others. It is also used in traditional medicine to cure fever, cholera, kidney stones, malaria, urinary tract infections, heat stroke and bleeding. Many studies have reported the positive effect of Cornelian cherry in regulating blood sugar and preventing fat accumulation in the liver. Similar to many countries, it is grown in Turkey in many regions and it is consumed processed or fresh into several crops such as compote, jam, marmalade and fruit leather. This paper has reviewed the investigative studies of the health effect of cornelian cherry.

Phenolic composition and in vitro antiproliferative activity of Borago spp. seed extracts on HT-29 cancer cells

Borage oil contains γ-linolenic acid (GLA, 18:3n-6), and significant amounts of tocopherols, sterols and squalene. However, data on phenolics are absent for most Borago species, while such compounds are relevant for improving human health. In this work, seeds of all endemic-wild Borago species and wild and farmed B. officinalis were surveyed for phenolic compound composition and in vitro antiproliferative activities. Phenolic analyses were conducted by HPLC-DAD and LC-MS, and antiproliferative activity were checked by the MTT assay. Besides a flavonol (kaemferol), 13 phenolic acids were identified and quantified. Among B. officinalis samples, the highest amounts of total phenolics and rosmarinic acid were found in the warmest and southernmost localities. Rosmarinic acid ranged from 12.21 (B. officinalis ‘Alba’ B2) to 105.06 mg/100 g seed (B. longifolia). Ferulic acid was also found in all Borago species, ranging from 1.38 in wild B. officinalis to 55.98 mg/100 g seed in B. longifolia. The MTT assay showed dose- and time-dependent inhibitory effects of Borago extracts on HT-29 cancer cells, with GI50 values within the 250–300 μg/mL range after 72 h of cell exposure to seeds extracts. Due to the occurrence of some compounds lacking antiproliferative activity in the crude phenolic extract, as evidenced by 1H NMR spectrum, the antiproliferative activity of the phenolics-containing extracts was lower than that obtained due to pure phenolics. This work constitutes the first approach to evaluate the phenolic composition of all Borago species and provides arguments for using endemic-wild Borago taxa by the pharmaceutical, cosmetic and food industries.

Composition of phenolic compounds in wastewater from the fixed-bed gasification of Baishihu coal

Crude phenols extracted using organic solvent from the wastewater of a typical fixed-bed gasification process was used as a raw material, and the distillation range was analyzed. The wide and narrow fractions of the raw material derived from distillation range analysis were cut using a real boiling point distillation device. The phenolic compounds in the different fractions were then qualitatively and quantitatively analyzed by gas chromatography after derivatization pretreatment. The yield of the < 290 °C fraction was 68.50% (mass fraction). A total of 33 effective phenolic compounds were identified in this fraction, and the percentage of identified phenols was nearly 80%. The contents of eight phenolic compounds were high, with phenol being the most abundant (26.34%) followed by catechol (13.44%). The contents of the remaining six abundant phenols ranged from 4% to 8%. The sum of the contents of m-cresol and p-cresol exceeded 12%, and the content of 5-indenol was nearly 8%. The yield of the fraction rich in low-grade phenols (< 230 °C) was 35.40%. The content of phenol in this fraction was more than 40%, the total content of cresol was over 23%, and the total content of m-cresol and p-cresol was nearly 20%. At room temperature, the 235–245 °C and 245–260 °C fractions were white crystals in which the catechol content was approximately 50%, and the 5-indenol content was more than 10%. The contents of these two high-value-added phenolic compounds are low in typical coal tar, making them difficult to extract. However, due to their strong polarity and good water solubility, catechol and 5-indenol are enriched in gasification wastewater by water selection, allowing their further extraction.

Phenolic compounds in the leaves and inflorescences of &lt;i&gt;Spiraea baldshuanica&lt;/i&gt; B. Fedtsch.

For the first time, the composition and content of phenolic compounds in the leaves and inflorescences of Spiraea baldshuanica B. Fedtsch. was investigated. Research material was collected in June 2019 from a natural population in the Republic of Tajikistan. Phenolic compounds were studied in 40% water- ethanol extracts by the method of high-performance liquid chromatography (HPLC). The analytical HPLC system used consisted of an Agilent 1200 (USA) liquid chromatograph equipped with a diode array detector, an autosampler and a ChemStation system for collecting and processing chromatographic data. 15 and 11 compounds of phenolic nature were found in native extracts from inflorescences and leaves, respectively. Among them, the following substances were identified: chlorogenic and cinnamic acids, quercetin, kaempferol, hyperoside, isoquercitrin, avicularin and astragalin. The chromatographic profiles of leaves and inflorescences were found to be different. Such substances as isoquercitrin, avicularin, kaempferol were discovered in the inflorescences of S. baldshuanica , rather than in its leaves. Compared to the leaves, the concentration of all detected phenolic compounds was higher in the inflorescences under study. The major component in the inflorescences was astragalin (3.16 mg/g), whereas its concentration in the leaves was 5 times lower (0.60 mg/g). Flavonoid aglycones were obtained from the water-ethanol extracts of the leaves and inflorescences under study by acid hydrolysis using hydrochloric acid (1:1). The hydrolysates of extracts from the leaves and inflorescences of S . baldshuanica were found to contain 3 flavonoid aglycones: quercetin, kaempferol and isorhamnetin. By recalculating the concentration of aglycone for the corresponding glycoside, it was determined that quercetin glycosides prevails: 6.67 mg/g – in the inflorescences and 1.19 mg/g – in the leaves. S. baldshuanica differs significantly from other representatives of the Spiraea genus, section Calospira , in terms of the chromatographic profile of phenolic compounds contained in the leaves. This information serves as an additional argument for differentiating S. baldshuanica as a separate series of the Decumbentes group by morphological signs.

Composition and Antioxidant Activity of Phenolic Compounds in Fruit of the Genus Rosa L.

We investigated the qualitative and quantitative composition of phenolic compounds in the fruit of Rosa L. cultivars grown in Lithuania. The highest total content of phenolic compounds (50.13 ± 4.17 mg GAE/g, p < 0.05) was determined in fruit samples of Rosa pimpinellifolia L. cultivar “Single Cherry”. The highest levels of hydroxycinnamic acid derivatives were determined in fruit samples of Rosa rugosa Thunb. cultivars “Dart’s Defender” and “Adam Chodun”. The highest flavonoid content was determined in fruit samples of Rosa multiflora Thunb. cultivar “Nana” and R. multiflora species. The strongest antioxidant activity evaluated by applying DPPH and FRAP assays was determined in fruit extracts of R. pimpinellifolia cultivar “Single Cherry” and R. rugosa cultivar “Adam Chodun”. Qualitative and quantitative analysis of phenolic compounds in Rosa L. fruit was performed by applying UHPLC. The following phenolic compounds were identified in fruit samples: caffeic acid, chlorogenic acid, quercetin, quercitrin, (+)-catechin, (−)-epicatechin, (−)-epicatechin gallate, rutin, phloridzin, and kaempferol-3-O-glycoside. A strong correlation was determined between the total amount of phenolic compounds determined in extracts of the fruit samples of Rosa L. cultivars and the radical scavenging and reducing activity of their extracts in vitro (R = 0.767 and 0.727, respectively, p < 0.05).

PHENOLIC COMPOUNDS AGRIMONIA PILOSA DEPENDING ON THE PHASE OF PLANT DEVELOPMENT

The composition and content of phenolic compounds in the organs of the above-ground part of Agrimonia pilosa Ledeb. depending on the phase of plant development were studied by high performance liquid chromatography (HPLC). Fourteen compounds found in water-ethanol extracts from organs of A. pilosa. Flavonols (kaempferol, astragalin, kaempferol-3-O-β-rutinoside, quercetin, hyperoside and rutin), flavones (apigenin, vitexin, luteolin and luteolin-7-glucoside) and phenolic acids (chlorogenic, caffeic, vanillic and ellagic acids) have been identified. Hyperoside, rutin, and ellagic acid were the major constituents in the extracts from the leaves and the reproductive organs of the species. The highest content of rutin were found in the leaves during vegetative growth and in the inflorescences (2.75 and 2.67 mg/g, respectively). The highest content of hyperoside were observed in leaves in the phase of budding and fruiting (2.02 and 2.25 mg/g). The highest content of ellagic acid were revealed in leaves in the fruiting phase and in buds (3.49 and 2.09 mg/g). The highest total phenolic content was found in the leaves during the fruiting (21.1 mg/g). Unidentified flavonols number 12 and 13 (1.62 and 2.76 mg/g, respectively) were the domi-nant components in the leaves in the growing phase. The total content of phenolic compounds in buds (9.52 mg/g) and in inflorescences (9.80 mg/g) was the same. The total content of phenolic compounds in fruits was two times less (4.24 mg/g) than in buds and inflorescences.

Phenolic Compounds and Biological Activity of Selected Mentha Species.

Mentha species are widely used as food, medicine, spices, and flavoring agents. Thus, chemical composition is an important parameter for assessing the quality of mints. In general, the contents of menthol, menthone, eucalyptol, and limonene comprise one of the major parameters for assessing the quality of commercially important mints. Building further on the phytochemical characterization of the quality of Mentha species, this work was focused on the composition of phenolic compounds in methanolic extracts. Thirteen Mentha species were grown under the same environmental conditions, and their methanolic extracts were subjected to the LC–MS/MS (liquid chromatography–tandem mass spectrometry) profiling of phenolics and the testing their biological activities, i.e., antioxidant and tyrosinase inhibition activities, which are important features for the cosmetic industry. The total phenolic content (TPC) ranged from 14.81 ± 1.09 mg GAE (gallic acid equivalents)/g for Mentha cervina to 58.93. ± 8.39 mg GAE/g for Mentha suaveolens. The antioxidant activity of examined Mentha related with the content of the phenolic compounds and ranged from 22.79 ± 1.85 to 106.04 ± 3.26 mg TE (Trolox equivalents)/g for M. cervina and Mentha x villosa, respectively. Additionally, Mentha pulegium (123.89 ± 5.64 mg KAE (kojic acid equivalents)/g) and Mentha x piperita (102.82 ± 15.16 mg KAE/g) showed a strong inhibition of the enzyme tyrosinase, which is related to skin hyperpigmentation. The most abundant compound in all samples was rosmarinic acid, ranging from 1363.38 ± 8323 to 2557.08 ± 64.21 μg/g. In general, the levels of phenolic acids in all examined mint extracts did not significantly differ. On the contrary, the levels of flavonoids varied within the species, especially in the case of hesperidin (from 0.73 ± 0.02 to 109. 39 ± 2.01 μg/g), luteolin (from 1.84 ± 0.11 to 31.03 ± 0.16 μg/g), and kaempferol (from 1.30 ± 0.17 to 33.68 ± 0.81 μg/g). Overall results indicated that all examined mints possess significant amounts of phenolic compounds that are responsible for antioxidant activity and, to some extent, for tyrosinase inhibition activity. Phenolics also proved to be adequate compounds, together with terpenoids, for the characterization of Mentha sp. Additionally, citrus-scented Mentha x villosa could be selected as a good candidate for the food and pharmaceutical industry, especially due its chemical composition and easy cultivation, even in winter continental conditions.