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

Abstract

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.

Non-thermal plasma as a pretreatment for extraction of herbal tea by-products

“…However, these extracts still had a higher antioxidant activity than those reported O N L I N E F I R S T in the literature. Vlase et al (2023) applied ultrasonic-assisted extraction on 30% (v/v) ethanol extracts of hoary willowherb and achieved around 90 mM TE/L extract using the ABTS method. These authors reported the total phenolic content of the same extract of approximately 5 mg GAE/mL extract (Vlase et al, 2023).…”

“…Vlase et al (2023) applied ultrasonic-assisted extraction on 30% (v/v) ethanol extracts of hoary willowherb and achieved around 90 mM TE/L extract using the ABTS method. These authors reported the total phenolic content of the same extract of approximately 5 mg GAE/mL extract (Vlase et al, 2023). For comparison, the average antioxidant activity of our hoary willowherb extracts was 4•10 5 mM TE/L, while the total phenolic content was around 35 mg GAE/mL extract on average.…”

Investigation of Epilobium hirsutum L. Optimized Extract’s Anti-Inflammatory and Antitumor Potential

“…Knowledge concerning indigenous Epilobium species remains incomplete and insufficient. This gap is particularly noteworthy given the abundance of these traditionally used medicinal plants within Romania’s native flora [ 27 ]. Considering that even minor variations in chemical composition can lead to significant disparities in bioactivity [ 20 , 21 , 28 ], the limited availability of scientifically supported data regarding Romania’s native flora poses a substantial limitation.…”

“…Recent years have witnessed a growing interest in the phytochemistry of Epilobium plants, commonly known as willow herbs [ 27 , 29 , 30 ], supported by recent discoveries highlighting their beneficial effects in various health conditions, most notably in the prevention and treatment of prostate ailments [ 31 , 32 ]. Traditional folk medicine practices have long used the properties of willow herb infusions in managing benign prostate hyperplasia (BPH), prostatitis, as well as disorders of the bladder, kidneys, and urinary tract [ 33 ].…”

“…Epilobium species’ plant materials are abundant in secondary metabolites, especially polyphenols and lipophilic substances with therapeutic significance [ 26 , 27 , 34 ]. These include sterols, such as ergosterol, beta-sitosterol, and campesterol, as well as tocopherols, (α-, γ-, and δ-tocopherol) [ 27 , 34 , 39 ].…”