Polyphenols, Antioxidant Activity and Volatile Compounds in Fermented Leaves of Medicinal Plant Rosebay Willowherb (Chamerion angustifolium (L.) Holub)

Polyphenols: Secondary Metabolites with a Biological Impression

Polyphenols are natural compounds which are plant-based bioactive molecules, and have been the subject of growing interest in recent years. Characterized by multiple varieties, polyphenols are mostly found in fruits and vegetables. Currently, many diseases are waiting for a cure or a solution to reduce their symptoms. However, drug or other chemical strategies have limitations for using a treatment agent or still detection tool of many diseases, and thus researchers still need to investigate preventive or improving treatment. Therefore, it is of interest to elucidate polyphenols, their bioactivity effects, supplementation, and consumption. The disadvantage of polyphenols is that they have a limited bioavailability, although they have multiple beneficial outcomes with their bioactive roles. In this context, several different strategies have been developed to improve bioavailability, particularly liposomal and nanoparticles. As nutrition is one of the most important factors in improving health, the inclusion of plant-based molecules in the daily diet is significant and continues to be enthusiastically researched. Nutrition, which is important for individuals of all ages, is the key to the bioactivity of polyphenols.

Epilobium Species: From Optimization of the Extraction Process to Evaluation of Biological Properties

Epilobium species are used in Romanian folk medicine as tinctures, tea, or tablets for ameliorating the symptoms of benign prostate hyperplasia (BPH), but scientific-based evidence is scarce for this species or other endemic plants of the same genus. Therefore, the aims of this research were to evaluate the phytochemical profile of five endemic Epilobium species (E. hirsutum L., E. parviflorum Schreb., E. palustre L. E. dodonaei Vill., and E. angustifolium L.) and to assess their in vitro biological activity. For enhanced recovery of polyphenols, a D-optimal experimental plan was developed using Modde software and the optimal working conditions were ultra-turrax-assisted extraction, for 8 min, with 30% ethanol in water. The optimized extracts were obtained from various plant parts and were further characterized by LC-MS analysis, with the major compound being oenothein B. All extracts demonstrated good antioxidant activity, evaluated by DPPH and TEAC assays. The most prominent antimicrobial potency of optimized extracts was displayed against Bacillus cereus, while against Gram-(+) bacteria, a moderate efficacy was observed. Furthermore, anti-cancer, anti-inflammatory, and antioxidant potential were assessed on normal fibroblasts and prostate carcinoma cell lines. From the evaluated optimized extracts, E. angustifolium aerial parts had the highest selectivity toward killing cancerous cells, followed by E. hirsutum aerial parts extract. For the antioxidant effect, E. hirsutum leaves and E. hirstum aerial parts extracts displayed the highest potency, decreasing ROS at the level observed for the positive control. The highest anti-inflammatory potential, based on the IL-6 and IL-8 levels, was displayed by E. dodonaei aerial parts and E. angustifolium leaves extracts. In conclusion, all five endemic species of Epilobium harvested from Romanian flora possess a diverse phytochemical composition, which supports complex biological activities.

Effect of Solid-State Fermentation on Vitamin C, Photosynthetic Pigments and Sugars in Willow Herb (Chamerion angustifolium (L.) Holub) Leaves

The goal of this investigation was to establish the impact of solid-state fermentation of different durations on the quantitative changes of vitamin C, sugars and photosynthetic pigments in the leaves of willow herbs. The tested leaves were fermented using two solid-state fermentation methods (aerobic and anaerobic) for different time periods (unfermented and fermented for 24, 48 and 72 h). The quantitative and qualitative composition of chlorophylls, carotenoids, sugars and vitamin C were determined using high performance liquid chromatography (HPLC) with UV detectors. Results indicated that aerobic and anaerobic solid-state fermentation significantly decreased the contents of vitamin C, dehydroascorbic and L-ascorbic acids in leaves compared with the unfermented leaves. The contents of total chlorophyll and chlorophyll a were the highest in unfermented leaves and after 24 h of aerobic solid-state fermentation. The maximum content of total carotenoids in leaves were after 48 and 72 h of aerobic solid-state fermentation (149.31 mg 100 g^-1 and 151.51 mg 100 g^-1, respectively). The application of anaerobic solid-state fermentation resulted in significant increase in the content of total sugars, fructose and glucose in investigated samples. In conclusion, optimization of fermentation parameters allows increasing the content of sugars and photosynthetic pigments in leaves of willow herbs.

Estimating the Mass of Food Components Necessary for the Utilization of Free Radical Particles in the Human Body

The article proposes an algorithm for an approximate assessment of the molar volume of free radicals generated in the human body per day. It takes into account the act of breathing, physical activity, food consumption, the influence of unfavorable environmental conditions, exposure to xenobiotics, as well as bad habits (alcohol and tobacco smoking). A calculation of the required set of the most commonly used food products for the disposal of free radicals was made. The calculation is a structure of four blocks with the possibility of adding optional data from human population genetic studies, environmental conditions, etc. In the proposed algorithm, the results of antiradical activity (ARA) of food products are used as input, including the results of predicting antiradical activity using artificial neural networks (ANN), which we published earlier. Based on the accepted values of one equivalent (in terms of the activity of 1 μmol of ascorbic acid), it was shown (for our data) that for the utilization of all free radicals produced in the human body per day, it will take an average of ≈260 to ≈540 g of food components in terms of dry mass (including proteins, fats, carbohydrates, etc.). At the same time, for the utilization of consumed xenobiotics, from 220 mg (in terms of vitamin C) to 260 mg (in terms of acetylcysteine -NAC) of additional plastic components or 11.5-13.0 g of essential amino acids will be required, which must be taken into account when calculating diets. This approach will be useful in the development of new functional foods, as well as in assessing the possible impact of diets on human health. Another applied point of this study is related to the possibility of using these data for better detailing and selection of food products for people working in conditions of increased radiation (in space conditions), in contact with harmful substances (chemical synthesis and production), for people practicing increased physical activity (bodybuilding and sports), and for the purposes of medical nutritional therapy.

Assessment of the Anti-Inflammatory, Antibacterial and Anti-Aging Properties and Possible Use on the Skin of Hydrogels Containing Epilobium angustifolium L. Extracts

Epilobium angustifolium L. is an ethnomedicinal plant known as a medicinal plant in many regions of the world, among others, in various skin diseases. Despite the great interest in this plant, there are still few reports of biological activity of ready-made dermatological or cosmetical preparations containing the E. angustifolium extracts. The antioxidant, anti-ageing, anti-inflammatory, antibacterial properties and toxicity, wound healing, and skin permeation of topical hydrogels containing E. angustifolium extracts (HEas) was assessed. First, the plant extracts were prepared using three solvents: 70% (v/v) ethanol, 70% (v/v) isopropanol and water, next by preparing hydrogels witch by dry extracts (HEa-EtOH), (HEa-iPrOH) and (HEa-WA), respectively. Finally, the content of selected phenolic acids in the HEas was evaluated by high-performance liquid chromatography (HPLC). All the HEas were characterized by high antioxidant activity. The most increased antibacterial activity was observed for a strain of Streptococcus pneumoniae ATCC 49619, Escherichia coli, Enterococcus faecalis ATCC 29212, Enterococcus faecium, Sarcina lutea ATCC 9341 and Bacillus pseudomycoides, while the strains of Streptococcus epidermidis, Bacillus subtilis, and Staphylococcus aureus were the least sensitive. All the HEas showed a reduction in the activity of lipoxygenase enzymes, proteases, and inhibition of protein denaturation. The HEa-EtOH and HEa-iPrOH also enhanced the wound healing activity of HDF cells. Additionally, in vitro penetration studies were performed using the Franz diffusion cells. These studies showed that the active ingredients contained in E. angustifolium penetrate through human skin and accumulate in it. Furthermore, the hydrogels containing E. angustifolium extracts showed a broad spectrum of activity. Therefore, they can be considered as an interesting alternative for dermatologic and cosmetic preparations.

Water-Soluble Melanoidin Pigment as a New Antioxidant Component of Fermented Willowherb Leaves (Epilobium angustifolium)

Willowherb (Epilobium angustifolium L., family Onagraceae) is a well-known food and medicinal plant used after fermentation as a source of beverages with high antioxidant potential. Despite this long history of use, only a few papers have described the chemical profile and bioactivity of fermented willowherb tea in general. To understand the basic metabolic differences of non-fermented and fermented E. angustifolium leaves, we used general chemical analysis, high-performance liquid chromatography with photodiode array detection and electrospray ionization triple quadrupole mass spectrometric detection assay, and an isolation technique. As a result, the content of 14 chemical groups of compounds was compared in the two plant materials; 59 compounds were detected, including 36 new metabolites; and a new water-soluble phenolic polymer of melanoidin nature was isolated and characterized. The fundamental chemical shifts in fermented E. angustifolium leaves relate mainly to the decrease of ellagitannin content, while there is an increase of melanoidin percentage and saving of the antioxidant potential, despite the significant changes detected. The strong antioxidative properties of the new melanoidin were revealed in a series of in vitro bioassays, and a simulated gastrointestinal and colonic digestion model demonstrated the stability of melanoidin and its antioxidant activity. Finally, we concluded that the new melanoidin is a basic antioxidant of the fermented leaves of E. angustifolium, and it can be recommended for additional study as a promising food and medicinal antioxidant agent.

Bacterial Cellulose Membrane Containing Epilobium angustifolium L. Extract as a Promising Material for the Topical Delivery of Antioxidants to the Skin

Bacterial cellulose membranes (BCs) are becoming useful as a drug delivery system to the skin. However, there are very few reports on their application of plant substances to the skin. Komagataeibacter xylinus was used for the production of bacterial cellulose (BC). The BC containing 5% and 10% ethanolic extract of Epilobium angustifolium (FEE) (BC-5%FEE and BC-10%FEE, respectively) were prepared. Their mechanical, structural, and antioxidant properties, as well as phenolic acid content, were evaluated. The bioavailability of BC-FESs using mouse L929 fibroblasts as model cells was tested. Moreover, In Vitro penetration through the pigskin of the selected phenolic acids contained in FEE and their accumulation in the skin after topical application of BC-FEEs was examined. The BC-FEEs were characterized by antioxidant activity. The BC-5% FEE showed relatively low toxicity to healthy mouse fibroblasts. Gallic acid (GA), chlorogenic acid (ChA), 3,4-dihydroxybenzoic acid (3,4-DHB), 4-hydroxybenzoic acid (4-HB), 3-hydroxybenzoic acid (3-HB), and caffeic acid (CA) found in FEE were also identified in the membranes. After topical application of the membranes to the pigskin penetration of some phenolic acid and other antioxidants through the skin as well as their accumulation in the skin was observed. The bacterial cellulose membrane loaded by plant extract may be an interesting solution for topical antioxidant delivery to the skin.

Epilobium angustifolium L. Extracts as Valuable Ingredients in Cosmetic and Dermatological Products

Epilobium angustifolium L. is a popular and well-known medicinal plant. In this study, an attempt to evaluate the possibility of using this plant in preparations for the care and treatment of skin diseases was made. The antioxidant, antiaging and anti-inflammatory properties of ethanolic extracts from Epilobium angustifolium (FEE) were assessed. Qualitative and quantitative evaluation of extracts chemically composition was performed by gas chromatography with mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). The total polyphenol content (TPC) of biologically active compounds, such as the total content of polyphenols (TPC), flavonoids (TFC), and assimilation pigments, as well as selected phenolic acids, was assessed. FEE was evaluated for their anti-inflammatory and antiaging properties, achieving 68% inhibition of lipoxygenase activity, 60% of collagenase and 49% of elastase. FEE also showed high antioxidant activity, reaching to 87% of free radical scavenging using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 59% using 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). Additionally, in vitro penetration studies were performed using two vehicles, i.e., a hydrogel and an emulsion containing FEE. These studies showed that the active ingredients contained in FEE penetrate through human skin and accumulate in it. The obtained results indicate that E. angustifolium may be an interesting plant material to be applied as a component of cosmetic and dermatological preparations with antiaging and anti-inflammatory properties.

Optimized ultrasound-assisted extraction of total polyphenols from Empetrum nigrum and its bioactivities

Optimization of ultrasound-assisted extraction (UAE) of total polyphenols (TPP) from Empetrum nigrum aerial parts was carried out by response surface methodology (RSM). The optimum UAE conditions of extraction time, extraction temperature, ethanol concentration, and solvent-to-material ratio were 21.38 min, 42.32 °C, 61.93% and 53.29:1 mL/g, respectively. Under the optimum conditions, the extraction yield of TPP was 32.17 ± 0.46 mg/g, which was 1.29-1.44 folds to those by the conventional extraction methods. In addition, the bioactivities of the extracts were investigated. Antioxidant activity test by the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay revealed that the TPP extracts had a high potential for free radical scavenging activity. The TPP extracts showed remarkable antibacterial activity against both Gram-positive and Gram-negative strains, especially against Gram-positive strains. The evaluation of antitumor activity by the MTT assay and flow cytometric analysis indicated that the TPP extracts significantly inhibited B 16F 10 melanoma cell proliferation and effectively induced apoptosis of melanoma cells. These results demonstrate that E. nigrum aerial parts are rich in TPP and show great application potential in the pharmaceutical industry.