The Potential of Medicinal Plants and Natural Products in the Treatment of Burns and Sunburn-A Review.

Treating burns remains a challenge for modern medicine, especially in developing countries that cannot afford expensive, advanced therapies. This review article summarises clinical and animal model studies of botanical preparations and their mixtures in treating burn wounds and sunburn. Articles available in electronic databases such as PubMed, Scopus, Web of Science, Science Direct and Google Scholar, published in English in 2010-2022, were considered. In the described clinical trials, it was shown that some herbal preparations have better effectiveness in treating burn wounds, including shortening the healing time and reducing inflammation, than the conventional treatment used hitherto. These herbal preparations contained extracts from Albizia julibrissin, Alkanna tinctoria, Aloe vera, Arnebia euchroma, Betula pendula and Betula pubescens, Centella asiatica, Hippophaë rhamnoides, Juglans regia, Lawsonia inermis, and mixtures of Matricaria chamomilla and Rosa canina. Research on animal models shows that many extracts may potentially benefit the treatment of burn wounds and sunburn. Due to the diverse mechanism of action, antibacterial activity, the safety of use and cost-effectiveness, herbal preparations can compete with conventional treatment. The growing interest in alternative medicine and herbal medicine encourages further research. Not only single preparations but also their mixtures should be taken into account because the research conducted so far often suggests a synergistic effect of the ingredients.

Current Knowledge on Interactions of Plant Materials Traditionally Used in Skin Diseases in Poland and Ukraine with Human Skin Microbiota.

Skin disorders of different etiology, such as dermatitis, atopic dermatitis, eczema, psoriasis, wounds, burns, and others, are widely spread in the population. In severe cases, they require the topical application of drugs, such as antibiotics, steroids, and calcineurin inhibitors. With milder symptoms, which do not require acute pharmacological interventions, medications, dietary supplements, and cosmetic products of plant material origin are gaining greater popularity among professionals and patients. They are applied in various pharmaceutical forms, such as raw infusions, tinctures, creams, and ointments. Although plant-based formulations have been used by humankind since ancient times, it is often unclear what the mechanisms of the observed beneficial effects are. Recent advances in the contribution of the skin microbiota in maintaining skin homeostasis can shed new light on understanding the activity of topically applied plant-based products. Although the influence of various plants on skin-related ailments are well documented in vivo and in vitro, little is known about the interaction with the network of the skin microbial ecosystem. The review aims to summarize the hitherto scientific data on plant-based topical preparations used in Poland and Ukraine and indicate future directions of the studies respecting recent developments in understanding the etiology of skin diseases. The current knowledge on investigations of interactions of plant materials/extracts with skin microbiome was reviewed for the first time.

Sambucus nigra L. leaves inhibit TNF-α secretion by LPS-stimulated human neutrophils and strongly scavenge reactive oxygen species.

ETHNOPHARMACOLOGICAL RELEVANCE: Sambucus nigra (elderberry) leaves were used in folk medicine to treat skin inflammations, ulcers, burns or boils, as well as to treat wounds, including infected and chronic ones. For centuries, elderberry leaves have been used mainly in eastern and southern Europe, as well as in western Asia. AIM OF THE STUDY: The study aimed to investigate the anti-inflammatory and antioxidant activity of four different extracts, such as aqueous and ethanolic prepared at room temperature and the solvent's boiling point, from the leaves of elderberry. MATERIALS AND METHODS: The effect of extracts both on the secretion of cytokines (TNF-α, IL-1ß, and IL-8) and reactive oxygen species (ROS) by neutrophils stimulated with bacteria-derived products was investigated. The cytotoxicity of extracts was analyzed by staining with propidium iodide measured by flow cytometry. The anti-inflammatory activity of extracts was also investigated through their influence on lipoxygenase activity. The antioxidant properties, including scavenging superoxide anion, hydrogen peroxide, nitric oxide, and 2,2-diphenyl-1-picrylhydrazyl radical were investigated in cell-free systems. The total content of phenolic compounds was tested using the Folin-Ciocalteu reagent. The qualitative and quantitative determination of the content of individual phenolic acids and flavonoids was performed by HPLC-DAD-MSn and HPLC-DAD method, respectively. RESULTS: Elderberry leaves extracts turned out to affect the inflammatory response of neutrophils by inhibiting the secretion of TNF-α and ROS. The ethanolic and aqueous extracts at a concentration of 50 µg × mL-1 reduce the secretion of TNF-α by approximately 40% and 10%, respectively. ROS secretion was decreased by around 50% for all extracts at concentration of 5 µg × mL-1. All the extracts were able to inhibit the activity of lipoxygenase. The ethanolic extracts were characterized by a higher content of phenolic compounds and a higher antioxidant activity, especially against nitric oxide, compared to the aqueous extracts. CONCLUSIONS: Our research has confirmed that elderberry leaves are a plant material with anti-inflammatory activity, especially against reactive oxygen species, and a potentially rich source of antioxidants. Preliminary analyses performed in this study could be the first step in confirming the traditional use of elderberry leaves in relieving inflammation.

Screening of Antioxidative Properties and Inhibition of Inflammation-Linked Enzymes by Aqueous and Ethanolic Extracts of Plants Traditionally Used in Wound Healing in Poland.

A wide range of plant-derived preparations have been used against skin inflammatory disorders and as wound healing agents in traditional medicine. The purpose of the study was to determine the antioxidant activity of aqueous and 70% ethanolic extracts from eleven species of plants traditionally used in Poland to treat inflammatory skin diseases. The ability of extracts to scavenge 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), hydrogen peroxide (H2O2), and superoxide anion (O2•-), was studied. In non-cellular studies, an analysis of the anti-inflammatory effect on the activity of enzymes, such as hyaluronidase (HYAL) and lipoxygenase (LOX), was also performed. The chemical profiles of the most active extracts were achieved by applying the UHPLC-DAD-MSn method, and the sum of polyphenols in all tested extracts was determined by the colorimetric method with the Folin-Ciocalteu reagent. The scope of the extracts' influence on enzyme activity was significantly lower than their antioxidant activity. All extracts have shown high activity in free radical scavenging against DPPH. The ethanolic extracts have shown high potential to scavenge H2O2. The study of composition showed that the main components of the tested extracts were flavonoids, such as luteolin, apigenin, kaempferol, and quercetin derivatives, as well as caffeoylquinic acids, caffeic acid, and its conjugates.

Characterization of herbal teas containing lime flowers - Tiliae flos by HPTLC method with chemometric analysis.

Linden trees are a source of food products called lime flowers (Tiliae flos), traditionally used in the form of infusion for the treatment of feverish colds and coughs. Lime flowers should include flowers of Tilia cordata Mill, T.x europaea L., and T. platyphyllos Scop. or a mixture of these. The aim of current research was to establish a fast, sensitive HPTLC (high-performance thin-layer chromatography) method that would allow the differentiation of material obtained from five species of lime occurring in Europe. The fingerprints for distinguishing these species were established, as well as a key for identification based on a visual evaluation of chromatograms. The results obtained were also subjected to chemometric analyses. It was shown that each species contains characteristic compounds i.e. linarin that can be used for their identification. The method developed can, in theory, be introduced for the quality control or authentication of linden flowers on the European market.

Arctium lappa and Arctium tomentosum, Sources of Arctii radix: Comparison of Anti-Lipoxygenase and Antioxidant Activity as well as the Chemical Composition of Extracts from Aerial Parts and from Roots.

Arctium lappa is a weed used in traditional medicine in the treatment of skin inflammation and digestive tract diseases. Arctium tomentosum is used in folk medicine interchangeably with Arctium lappa and, according to European Medicines Agency (EMA) monography, provides an equal source of Arctii radix (Bardanae radix), despite the small amount of research confirming its activity and chemical composition. The aim of the study was the comparison of the anti-lipoxygenase and the antioxidant activity, scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide anion (O2•-), and hydrogen peroxide (H2O2), of 70 % (v/v) ethanolic extracts from the aerial parts and the roots of Arctium lappa and Arctium tomentosum. In the tested extracts, the total polyphenols content and the chemical composition, analyzed with the HPLC-DAD-MSn method, were also compared. The extracts were characterized by strong antioxidant properties, but their ability to inhibit lipoxygenase activity was rather weak. A correlation between the content of polyphenolic compounds and antioxidant activity was observed. The extracts from A. lappa plant materials scavenged reactive oxygen species more strongly than the extracts from A. tomentosum plant materials. Moreover, the extracts from A. lappa plant materials were characterized by the statistically significantly higher content of polyphenolic compounds.

Immunomodulatory Activity and Phytochemical Profile of Infusions from Cleavers Herb.

Extracts from aerial parts of G. aparine (cleavers) constitute a herbal remedy with monography in British Herbal Pharmacopeia. On the European market, there are several drugs and food supplements consisting of Galium extracts. In folk medicine, cleavers was used topically in Europe, Asia, and the Americas to treat skin diseases. In several remedies, cleavers is also listed as an immunomodulatory active herb influencing the defense response of the human body. The aim of this study was to investigate the immunostimulatory activity and antioxidant potential in vitro of a raw infusion of cleavers and bioactive fractions. The functional activity of lymphocytes in the reaction of the lymphocyte blast transformation (RLBT) method was used for immunomodulatory activity assays and direct scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO), and hydrogen peroxide (H2O2) was chosen for the examination of antioxidant activity. It was shown that both the raw extract and fractions show significant immunostimulatory and scavenging activities. The obtained data partially justify the traditional use of cleavers as topical remedy for skin infections and for wounds.

Lamalbid, Chlorogenic Acid, and Verbascoside as Tools for Standardization of Lamium album Flowers-Development and Validation of HPLC-DAD Method.

Preparations from the flowers or herb of the white dead nettle (Lamium album L.) are recommended for the treatment of upper respiratory tract disorders or as a topical medication for mild inflammation of the throat, mouth, and skin. Taking into consideration the significance of L. album in traditional medicines across Europe, as well as the lack of studies describing the quantities of their most abundant constituents, we aimed to design a high-performance liquid chromatography coupled with diode-array detection (HPLC-DAD) method for potential standardization procedures of extracts from flowers of L. album. The HPLC-DAD method was developed and validated for quantification of iridoids (lamalbid), phenolic acids/depsides (chlorogenic acid), phenylpropanoids (verbascoside), and flavonoids (rutin; quercetin malonylhexoside; tiliroside) in aqueous and ethanolic-aqueous extracts of Lamii albi flos. The method was specific, accurate, and precise. Lamalbid was the most abundant compound both in aqueous (39.09 ± 1.02 m/g dry weight) and ethanolic-aqueous (26.66 ± 0.64 m/g dry weight) extracts. The quantities of selected compounds, except for chlorogenic acid and tiliroside, were higher in the aqueous extract than in the ethanolic-aqueous one. In conclusion, the method developed allowed for quantitation of compounds from different classes. In particular, chlorogenic acid and verbascoside have been proposed as reference compounds for routine quantitative control of Lamii albi flos.

Phytochemical Profiles and In Vitro Immunomodulatory Activity of Ethanolic Extracts from Galium aparine L.

Galium aparine L., family Rubiaceae, is a widely spread species in the Galium genus. The herb of G. aparine is part of folk remedies and dietary supplements. In this study, we analyzed the chemical composition and immunomodulatory activities of G. aparine herb ethanolic extracts obtained from the plant material by maceration with 20%, 60% or 96% ethanol. The contents of hydroxycinnamic acid derivatives, flavonoids and polyphenols were determined spectrophotometrically, with extractives and polysaccharides quantified gravimetrically. The qualitative composition was studied using UHPLC-DAD-MS/MS analysis; isolation not previously described in G. aparine quercetin rhamnoglucoside was carried out through column chromatography, and the immunomodulatory activity of extracts was determined in the reaction of lymphocyte blast transformation. Major constitutes of extracts were iridoids, i.e., monotropein, 10-desacetylasperulosidic acid and asperulosidic acid; p-hydroxybenzoic acid; hydroxycinnamic acid derivatives, i.e., 3-O-caffeoylquinic, 5-O-caffeoylquinic, 3,4-O-dicaffeoylquinic, 3,5-O-dicaffeoylquinic, 4,5-O-dicaffeoylquinic acids and caffeic acid derivatives; flavonoids, i.e., rutin, quercetin 3-O-rhamnoglucoside-7-O-glucoside, and isorhamnetin 3-O-glucorhamnoside. Significantly, quercetin 3-O-rhamnoglucoside-7-O-glucoside was first isolated and identified in Galium species so far investigated. All G. aparine herb ethanolic extracts stimulate the transformational activity of immunocompetent blood cells, with 96% ethanolic extract being the most active. The data obtained necessitate further research into the mechanisms of immunomodulatory activity of extracts from G. aparine herb.

Anthocyans-rich Aronia melanocarpa extract possesses ability to protect endothelial progenitor cells against angiotensin II induced dysfunction.

BACKGROUND: Endothelial progenitor cells (EPC) may provide protection against atherosclerosis and plaque rupture by their innate ability to replace dysfunctional or damaged endothelial cells in plaque microvessels. There is evidence that angiotensin II may impair the angiogenic functions of EPCs in the atherosclerotic plaque by accelerating senescence and inhibiting their proliferation through oxidative stress induction. PURPOSE: In this study, we examined whether chokeberry (Aronia melanocarpa) fruit extract, containing mainly anthocyanins with potent antioxidative properties, could protect EPCs against angiotensin-induced oxidative stress. METHODS: EPCs were isolated from peripheral blood of young healthy volunteers and cultivated on fibronectin-coated plates in the presence or absence of angiotensin II (1 µM) and chokeberry extract (1-25 µg/ml). RESULTS: EPCs exposed to chokeberry extract prior to angiotensin II showed a significant increase of proliferation and telomerase activity, and a decrease in the percentage of senescent cells and intracellular ROS formation in comparison to angiotensin II treated cells. Furthermore, extract increased migration ability, adhesion to fibronectin and the angiogenic potential of EPC in vitro diminished by angiotensin II in a concentration-dependent manner. That effect was related to the activation of the Nrf2 transcription factor and the increase of HO-1 expression. CONCLUSIONS: Our results suggested that chokeberry extract may protect EPCs against angiotensin II-induced dysfunction and could play a potential role in the prevention of coronary artery disease.

Determination of in vitro antioxidant and UV-protecting activity of aqueous and ethanolic extracts from Galinsoga parviflora and Galinsoga quadriradiata herb.

Galinsoga species are used in folk medicine as anti-inflammatory agents and accelerators for wound healing. They also have reported antioxidant activity. We examined aqueous and ethanolic extracts derived from the Galinsoga herb as potential photoprotectors, as the role of reactive oxygen species (ROS) has implicated in skin damage. The extracts used in the study were standardized by determining the sum of flavonoids, and the amount of caffeic acid and its derivatives. The antioxidant activity of the extracts was evaluated by examining the scavenging of two radicals (O2(-) and H2O2) generated in cell-free systems. We also examined the effect on ROS generation by human skin fibroblasts after UV irradiation. In addition we determined the cytotoxicity of the extracts and their protective effect against damage caused by UV irradiation (MTT test, LDH release test and staining with annexine V-FITC/PI). Our findings show that the ethanolic extracts from the herb have cytotoxic effects, while the aqueous extracts from Galinsoga herb have protective activity, in part due to their ability to inhibit ROS generation. In the conclusion the aqueous extracts from the both tested species may be effective as photoprotectors.

Quantitative Determination of Secoiridoids and Phenylpropanoids in Different Extracts of Ligustrum Vulgare L. Leaves by a Validated HPTLC-Photodensitometry Method.

INTRODUCTION: The genus Ligustrum (Oleaceae) is distributed in Europe and Asia (south China and Korea), where it is used to prevent hypertension, sore throats, inflammation and diabetes. The main groups of compounds in extracts of Ligustrum vulgare are biologically active secoiridoids and phenylpropanoids. OBJECTIVES: The aim of the study was primarily the development and validation of a HPTLC-photodensitometry method for separation and determination of secoiridoids (oleacein, oleuropein) and phenylpropanoids (echinacoside) in different extracts prepared from leaves of L. vulgare. A secondary issue was the quantitative screening of oleacein, oleuropein and echinacoside in extracts from leaves collected at different stages of plant growth (from May to September). METHODS: A HPTLC-photodensitometry method was developed and validated for quantification of oleuropein, oleacein and echinacoside in plant extracts (aqueous and ethanolic extract, decoction, infusion). Silica gel was used as the stationary phase and dichloromethane:methanol:formic acid:water (80:25:1.5:4, v/v/v/v) as the mobile phase. RESULTS: The HPTLC-photodensitometry method developed for quantification of oleacein, oleuropein and echinacoside was specific, accurate and precise. The presence of oleacein was detected in aqueous extracts, whereas oleuropein was present, in particular, in ethanolic extracts, decoctions and infusions. Echinacoside was detected in all the extracts prepared. The content of secoiridoids was variable from May to September, whereas the amount of echinacoside increased in this term. CONCLUSION: The developed and validated HPTLC-photodensitometry method allowed performing fast screening of quantitative profiles of oleacein, oleuropein and echinacoside in preparations of privet leaves.

Reactive Nitrogen Species Scavenging Capacity of Aqueous and Ethanolic Extracts from Galinsoga parviflora and G. quadriradiata Herbs.

The aim of the study was to determine the scavenging capacity of aqueous and ethanolic extracts derived from the herb of two species of Galinsoga against NO and ONOO-. In both tests the aqueous extracts of both Galinsoga species were more active than the ethanolic extracts. The highest scavenging activity against NO, and also against ONOO- was shown by G. quadriradiata aqueous extract (SC50 ± SD = 1.54 ± 0.32, and 2.10 ± 1.98, respectively). The study showed that the activity of the extracts from both Galinsoga species is related not only to the presence of flavonoids but also to caffeic acid derivatives and caffeic acid. The results of this study partly explain the beneficial effects of Galinsoga herb extracts in the treatment of skin diseases.

Polyphenolic Profile, Antioxidant and Anti-Inflammatory Activity of Eastern Teaberry (Gaultheria procumbens L.) Leaf Extracts.

Dry leaf extracts of eastern teaberry (Gaultheria procumbens L.) were evaluated as a source of bioactive phytocompounds through systematic activity testing and phytochemical profiling. The antioxidant efficiency was tested using five complementary in vitro models (DPPH; FRAP; linoleic acid (LA) peroxidation assay; O2•- and H2O2 scavenging tests) in parallel with standard antioxidants. The 75% methanol extract and its diethyl ether, ethyl acetate (EAF), n-butanol and water fractions exhibited the dose-dependent responses in all assays, with the highest capacities found for EAF (DPPH EC50 = 2.9 µg/mL; FRAP = 12.8 mmol Fe2+/g; IC50 for LA-peroxidation = 123.9 µg/mL; O2•- SC50 = 3.9 µg/mL; H2O2 SC50 = 7.2 µg/mL). The EAF had also the highest anti-inflammatory activity in the inhibition tests of lipoxygenase and hyaluronidase (60.14% and 21.83% effects, respectively, at the concentration of 100 µg/mL). Activity parameters of the extracts correlated strongly with the levels of total phenolics (72.4-270.7 mg GAE/g), procyanidins, and phenolic acids, whereas for flavonoids only moderate effects were observed. Comprehensive UHPLC-PDA-ESI-MS3 and HPLC-PDA studies led to the identification of 35 polyphenols with a procyanidin A-type trimer, quercetin 3-O-glucuronide, isomers of caffeoylquinic acids, and (‒)-epicatechin being the dominant components. Significant activity levels, high phenolic contents and high extraction yields (39.4%-42.5% DW for defatted and crude methanol extracts, respectively) indicate the value of eastern teaberry leaves as bioactive products.

In vitro antioxidant and anti-inflammatory activities of extracts from Potentilla recta and its main ellagitannin, agrimoniin.

ETHNOPHARMACOLOGICAL RELEVANCE: Potentilla recta is one of the numerous cinquefoil species growing in Poland. It is used in traditional medicine e.g. in the treatment of skin inflammation. AIM OF THE STUDY: The purpose of the present study is to evaluate antioxidant and anti-inflammatory activities of extracts and subfractions of the P. recta herb (obtained by using solvents of different polarity) in in vitro systems as well as to examine their chemical composition. MATERIALS AND METHODS: Antioxidant activities of the extracts, subfractions and agrimoniin were evaluated using DPPH and three other radicals (O2(-), H2O2, and HClO) generated in cell-free systems. Anti-hyaluronidase activity was measured by using the turbidimetric method. Inhibition of lipoxidase activity was measured spectrophotometrically, using linoleic acid as a substrate. The composition of the most active subfraction was determined using the HPLC-DAD-MS(n) method. RESULTS: All tested samples showed scavenging activity against all the examined reactive species in a concentration-dependent manner. The highest scavenging activity against DPPH, H2O2 and HClO was observed in the ethyl acetate subfraction (PRE3) (SC50 ± SEM [µg/mL]: 25.39 ± 2.49, 1.79 ± 0.25 and 8.52 ± 1.16 respectively). It was only in the xanthine/xanthine oxidase system that the antioxidation potential of the diethyl ether subfraction (PRE2) (SC50 ± SEM [µg/mL]: 6.59 ± 1.33) was higher than that of the subfraction PRE3 (SC50 ± SEM [µg/mL]: 8.57 ± 1.37). Also, in the studies of lipoxidase and hyaluronidase inhibition activity the strongest effect was observed for PRE3, with IC50 [µg/mL] = 86.31 ± 5.46, and 12.99 ± 1.31, respectively. The chromatographic method (HPTLC-DPPH) revealed that the principal substance responsible for the activity, is a tannin like compound. Isolated agrimoniin showed significant reactive oxygen species scavenging activity and significant enzyme inhibition activity (including xanthine oxidase inhibition activity). Agrimoniin exerted the strongest scavenging activity against H2O2 (SC50 ± SEM [µM]: 0.20 ± 0.01). This compound also significantly inhibited the enzymatic activity of lipoxidase (IC50 [µM] = 36.47 ± 1.29), and, particularly, of hyaluronidase (IC50 [µM] = 2.65 ± 0.40). CONCLUSIONS: The strong scavenging activity against H2O2, and the inhibition of the enzymatic activity of lipoxidase, and particularly, hyaluronidase observed for the tested subfractions and agrimoniin, partly explain the beneficial effects of P. recta in treatment of skin inflammation.

Inhibition of NF-κB-dependent cytokine and inducible nitric oxide synthesis by the macrocyclic ellagitannin oenothein B in TLR-stimulated RAW 264.7 macrophages.

Immunomodulatory effects of oenothein B (1), a macrocyclic ellagitannin from various Onagraceae species, have been described previously. However, the mechanisms underlying the anti-inflammatory activity of 1 have not been fully clarified. The effects of 1 were investigated on inducible nitric oxide synthase, TLR-dependent and TLR-independent signal transduction cascades, and cytokine expression using murine macrophages (RAW 264.7). Compound 1 (10-60 µg/mL) reduced NO production, iNOS mRNA, and iNOS protein levels in a dose-dependent manner, without inhibition of iNOS enzymatic activity. It reduced the binding of the NF-κB p50 subunit to the biotinylated-consensus sequence and decreased nuclear p65 translocation. Gallic acid as a subunit of the macrocyclic ellagitannin 1 showed a far lower inhibitory activity. Nitric oxide production was reduced by 1 after stimulation using TLR2 (Pam2CSK4) and TLR4 (Kdo2) agonists, but this compound did not inhibit inducible nitric oxide synthesis after stimulation using interferon-gamma. IL-1beta, IL-6, and TNF-alpha mRNA synthesis was clearly reduced by the addition of 1. Oenothein B (1) inhibits iNOS after stimulation with LPS, TLR2, and TLR4 agonists via inhibition of TLR/NF-κB-dependent inducible nitric oxide and cytokine synthesis independent from IFN-gamma/JAK/STAT pathways. The full molecular structure of this macrocyclic ellagitannin seems to be required for its immunomodulatory actions.

Determination of macrocyclic ellagitannin oenothein B in plant materials by HPLC-DAD-MS: method development and validation.

INTRODUCTION: Oenothein B (OeB) is a dimeric macrocyclic ellagitannin occurring mainly in the genus Oenothera. In the literature no validated HPLC method for quantification of this compound has been reported. OBJECTIVE: To develop and validate an efficient HPLC method for quantification of OeB in plant materials. METHODOLOGY: Extraction conditions of OeB from plant material were optimised. Then the first validated HPLC method for quantification was developed. RESULTS: We have shown that ultrasonic-assisted extraction at 40 °C in 15 min using water are the most optimal conditions for OeB extraction. We have quantified OeB in several plant materials belonging to Oenotheraceae family. The lowest amount of OeB was present in Circaea lutetiana herb (27.64 ± 0.26 mg/g) and the highest was quantified in Epilobium hirsutum aerial parts (72.91 ± 1.38 mg/g). CONCLUSION: The first HPLC method for quantification of OeB in plant materials was developed and validated. We also for the first time optimised the extraction conditions for OeB.

Method development and validation for optimized separation of quercetin derivatives in selected Potentilla species using high-performance thin-layer chromatography photodensitometry method.

A novel HPTLC-densitometry method was developed for separation and quantitative determination of four flavonoids: quercetin 3-O-ß-d-glucuropyranoside (miquelianin; QG), quercetin 3-O-ß-d-glucopyranoside (isoquercitrin; IQ), quercetin 3-O-ß-d-galactopyranoside (hyperoside; HYP) and quercetin 3-O-ß-d-(6″-α-l-rhamnosylo)-glucopyranoside (rutin; RUT) in ethyl acetate fractions from aerial parts of selected Potentilla species: P. argentea, P. erecta, Dasiphora fruticosa (syn. P. fruticosa), Drymocallis rupestris (syn. P. rupestris), P. nepalensis var. 'Miss Wilmott' and P. thuringiaca. For the first time, separation of this type of flavonoids was achieved on a HPTLC DIOL F(254) plates using a mixture consisting of ethyl acetate/methyl ethyl ketone/diisopropyl ether/formic acid (3:10:4:1, v/v/v/v). QG, IQ, HYP and RUT were determined by densitometry at 363 nm. Sensitivity, accuracy (recovery rates were between 95.0 and 101.4%) and precision (in both cases intra-day precision and inter-day precision were ≤ 8.0%) of the method were determined. Their amounts were calculated using the regression equations of the calibration curves which were linear in a range of 0.025-0.200 µg/spot for all investigated compounds. The amounts of marker compounds in ethyl acetate extracts of Potentilla species measured by the method ranged between 16.7 ± 1.1 and 41.7 ± 0.6 mg/g for QG, 15.8 ± 1.3 and 36.7 ± 1.0mg/g for IQ, 14.5 ± 0.5mg/g for HYP and 6.7 ± 0.3 and 27.8 ± 2.1mg/g for RUT. The method was found to be relatively simple, specific, precise and accurate and may be used for the quality control of simultaneous determination of quercetin derivatives in Potentilla extracts but also in other similar plant materials.

Determination of antioxidant activity of extracts and fractions obtained from Galinsoga parviflora and Galinsoga quadriradiata, and a qualitative study of the most active fractions using TLC and HPLC methods.

Taking into account the role of reactive oxygen species in the development of inflammation, and the application of the plants of genus Galinsoga Ruiz & Pav. in folk medicines for inflammatory states, we investigated and compared the antioxidant activities of particular Galinsoga extracts and fractions. The compositions of the most active fractions were studied using thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC) methods. The extracts and fractions from Galinsoga parviflora Cav. and Galinsoga quadriradiata Ruiz et Pav. possess dose-dependent free radical-scavenging ability against DPPH• and superoxide radicals, as well as inhibitory effects on linoleic acid peroxidation in a manner comparable to gallic acid. In the most active fractions, flavonoids, patulitrin, quercimeritrin, quercitagetrin and caffeoyl derivatives were detected. Our research demonstrates that the investigated herbs are an interesting source of preparations with significant antioxidant effects. Our results justify the use of both raw materials in inflammatory diseases, among others, due to their ability to prevent free radical-induced deleterious effects.

Oenothein B's contribution to the anti-inflammatory and antioxidant activity of Epilobium sp.

Willow herb tea or preparation are available and relatively popular in the European market, and claimed to be effective inter alia because of their anti-inflammatory activity. The present study is therefore aimed at comparing the anti-inflammatory and antioxidant activity of extracts of the three most popular Epilobium species (E. angustifolium, E. hirsutum and E. parviflorum) and at juxtaposing this activity against the dominating compounds from the following extracts: oenothein B (OeB), quercetin-3-O-glucuronide and myricetin-3-O-rhamnoside. The phytochemical analysis of the extracts has shown that OeB quantities vary between 20% and 35%, while flavonoids content does not exceed 2%. All extracts have inhibited the activity of hyaluronidase and lipoxygenase with IC50 around 5 µg/ml and 25 µg/ml. The inhibition of hyaluronidase is related with the presence of OeB, a strong inhibitor of this enzyme (IC50) 1.1 µM). Additionally, the extracts inhibited myeloperoxidase (MPO) release from stimulated neutrophils. OeB inhibited MPO release similarly to the anti-inflammatory drug indomethacin with IC50 7.7 µM and 15.4 µM, respectively. Tested extracts significantly reduced the production of reactive oxygen species (ROS) from f-MLP and PMA induced neutrophils with IC50 5 µg/ml and 25 µg/ml, respectively. The flavonoids content seems to exert little influence on extracts' activity, contrary to OeB, whose high concentration explains the activity of extract obtained from Epilobium. Tested currently marketed Epilobium preparations are often wrongly assigned, but we should stress that the level of OeB in all tested herbs was high and always exceeded 2% in raw material.